[Clinicopathological characteristics and prognosis of non-Hodgkin lymphoma in oral and maxillofacial regions: An analysis of 369 cases].

OBJECTIVE: To investigate the clinicopathological characteristics and factors influencing the prognosis of non-Hodgkin lymphoma (NHL) in oral and maxillofacial regions. METHODS: Clinicopathological data of 369 patients with oral and maxillofacial NHL initially diagnosed in Peking University Hospital of Stomatology from 2008 to 2020 were collected and analyzed retrospectively. RESULTS: There were 180 males and 189 females. The median age of the patients was 56 years (3 months to 92 years), and the median duration was three months. Clinically, 283 cases manifested as mass, 38 cases as ulcerative necrotizing lesions, and 48 cases as diffuse soft tissue swelling. The lesions of 90 cases located in face and neck (75 cases neck, 20.3%), 99 cases were of major salivary glands (79 cases parotid glands, 20.9%), 103 cases of oral cavity, 50 cases of maxillofacial bones, 20 cases of Waldeyer's ring, and 7 cases of infratemporal fossa. In the study, 247 of the 369 patients had cervical lymphadenopathy, only 40 cases had B symptoms, and 23 cases had the bulky disease. Of the 369 NHLs, 299 (81%) were B-cell NHL, and 70(19%) were T-cell NHL. Diffuse large B-cell lymphoma, extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue, follicular lymphoma, and extranodal natural killer (NK)/T-cell lymphoma nasal type were the most common pathological subtypes. According to Ann Arbor staging, 87, 138, 106, and 38 cases were classified as staged Ⅰ, Ⅱ, Ⅲ, Ⅳ, respectively. The me-dian follow-up time was 48 months, 164 patients died during the follow-up period. The overall survival rates for one year, two years, and five years were 90.1%, 82.4%, and 59.9%, respectively, and the median survival was (86.00±7.98) months. Multivariate analysis showed that age (P < 0.001), Ann Arbor staging (P < 0.001), elevated lactate dehydrogenase (P=0.014), and pathological subtype (P=0.049) were the independent factors influencing the overall survival rate of NHL patients. CONCLUSION: Oral and maxillofacial NHL has unique clinical characteristics and distribution patterns of pathological subtypes. Fewer patients had systemic symptoms. Neck and parotid glands were the most common sites invaded by NHL. Advanced age, Ann Arbor stage Ⅲ-Ⅳ, B symptoms, and T-cell NHL may predict a poor prognosis in oral and maxillofacial NHL patients.

[Recent progress in the treatment of intractable sialolithiasis].

Sialolithiasis occurs in approximately 0.45% to 1.20% of the general population. The typical clinical symptom manifests as a painful swelling of the affected glands after a meal or upon salivary stimulation, which extremely affects the life quality of the patients. With the development of sialendoscopy and lithotripsy, most sialoliths can be successfully removed with preservation of the gland. However, sialoliths in the deep hilar-parenchymal submandibular ducts and impacted parotid stones located in the proximal ducts continue to pose great challenges. Our research center for salivary gland diseases (in Peking University School and Hospital of Stomatology) has used sialendoscopy for 17 years and treated >2 000 patients with salivary gland calculi. The success rate was approximately 92% for submandibular gland calculi and 95% for parotid calculi. A variety of minimally invasive surgical techniques have been applied and developed, which add substantial improvements in the treatment of refractory sialolithiasis. Further, the radiographic positioning criteria and treatment strategy are proposed for these intractable stones. Most of the hilar-parenchymal submandibular stones are successfully removed by a transoral approach, including transoral duct slitting and intraductal basket grasping, while a small portion of superficial stones can be removed by a mini-incision in submandibular area. Impacted stones located in the distal third of parotid gland ducts are removed via "peri-ostium incision", which is applied to avoid a cicatricial stenosis from a direct ostium incision. Impacted parotid stones located in the middle and proximal third of the Stensen's duct are removed via a direct mini-incision or a peri-auricular flap. A direct transcutaneous mini-incision is commonly performed under local anesthesia with an imperceptible scar, and is indicated for most of impacted stones located in the middle third, hilum and intraglandular ducts. By contrast, a peri-auricular flap is performed under general anesthesia with relatively larger operational injury of the gland parenchyma, and should be best reserved for deeper intraglandular stones. Laser lithotripsy has been applied in the treatment of sialolithiasis in the past decade, and holmium ∶YAG laser is reported to have the best therapeutic effects. During the past 3 years, our research group has performed laser lithotripsy for a few cases with intractable salivary stones. From our experiences, withdrawal of the endoscopic tip 0.5-1.0 cm away from the extremity of the laser fiber, consistent saline irrigation, and careful monitoring of gland swelling are of vital importance for avoidance of injuries of the ductal wall and the vulnerable endoscope lens during lithotripsy. Larger calculi require multiple treatment procedures. The risk of ductal stenosis can be alleviated by endoscopic dilation. In summary, appropriate use of various endoscopy-assisted lithotomy helps preserve the gland function in most of the patients with refractory sialolithiasis. Further studies are needed in the following aspects: Transcervical removal of intraglandular submandibular stones, intraductal laser lithotripsy of impacted parotid stones and deep submandibular stones, evaluation of long-term postoperative function of the affected gland, et al.

[The impact of extended waiting time on tumor regression after neoadjuvant chemoradiotherapy for locally advanced rectal cancer].

Objective: To investigate the influence of extending the waiting time on tumor regression after neoadjuvant chemoradiology (nCRT) in patients with locally advanced rectal cancer (LARC). Methods: Clinicopathological data from 728 LARC patients who completed nCRT treatment at the First Affiliated Hospital, Naval Medical University from January 2012 to December 2021 were collected for retrospective analysis. The primary research endpoint was the sustained complete response (SCR). There were 498 males and 230 females, with an age (M(IQR)) of 58 (15) years (range: 22 to 89 years). Logistic regression models were used to explore whether waiting time was an independent factor affecting SCR. Curve fitting was used to represent the relationship between the cumulative occurrence rate of SCR and the waiting time. The patients were divided into a conventional waiting time group (4 to <12 weeks, n=581) and an extended waiting time group (12 to<20 weeks, n=147). Comparisons regarding tumor regression, organ preservation, and surgical conditions between the two groups were made using the t test, Wilcoxon rank sum test, or χ2 test as appropriate. The Log-rank test was used to elucidate the survival discrepancies between the two groups. Results: The SCR rate of all patients was 21.6% (157/728). The waiting time was an independent influencing factor for SCR, with each additional day corresponding to an OR value of 1.010 (95%CI: 1.001 to 1.020, P=0.031). The cumulative rate of SCR occurrence gradually increased with the extension of waiting time, with the fastest increase between the 10th week. The SCR rate in the extended waiting time group was higher (27.9%(41/147) vs. 20.0%(116/581), χ2=3.901, P=0.048), and the organ preservation rate during the follow-up period was higher (21.1%(31/147) vs. 10.7%(62/581), χ2=10.510, P=0.001). The 3-year local recurrence/regrowth-free survival rates were 94.0% and 91.1%, the 3-year disease-free survival rates were 76.6% and 75.4%, and the 3-year overall survival rates were 95.6% and 92.2% for the conventional and extended waiting time groups, respectively, with no statistical differences in local recurrence/regrowth-free survival, disease-free survival and overall survival between the two groups (χ2=1.878, P=0.171; χ2=0.078, P=0.780; χ2=1.265, P=0.261). Conclusions: An extended waiting time is conducive to tumor regression, and extending the waiting time to 12 to <20 weeks after nCRT can improve the SCR rate and organ preservation rate, without increasing the difficulty of surgery or altering the oncological outcomes of patients.

[Effects of acid stimulation on saliva flow rate and compositions of human parotid and submandibular glands].

OBJECTIVE: To investigate the effect of acid stimulation on salivary flow rate and compositions of human parotid and submandibular glands, so as to provide basis for comprehensive evaluation of salivary gland function in both health and disease status. METHODS: In the study, 210 healthy participants' whole saliva samples were collected under passive drooling, and their parotid gland and submandibular gland secretions were collected by negative pressure suction. 2% citric acid was dropped on the tip of tongue every 1 min for acid stimulation for a total of 5 times to collect stimulated whole saliva, parotid and submandibular gland saliva. The collected saliva was weighed and saliva flow rate was calculated. The K+, Na+, Cl-, Ca2+, total protein, total phosphorus and α-amylase in saliva samples were detected by biochemical analyzer, and the changing features of flow rate and compositions of different kinds of saliva were compared and analyzed. RESULTS: After acid stimulation, saliva flow rate significantly increased. The increase proportion of parotid gland saliva (10.7 folds) was much higher than that of submandibular gland saliva (2.9 folds). The concentrations of Na+, Cl-, Ca2+, total protein and α-amylase in parotid gland saliva increased significantly (P < 0.05), but there was no significant difference in total phosphorus and K+ (P=0.89, P=0.34). The concentration of Na+ and Ca2+ in saliva of submandibular gland increased significantly(P < 0.05), the concentration of total phosphorus decreased significantly(P < 0.05), and the concentration of Cl- increased, but the difference was not significant(P=0.068). There was no significant difference in total protein, K+ and α-amylase (P=0.85, P=0.07, P=0.95). The compound secretion rate of total phosphorus in saliva of submandibular gland remained unchanged(P=0.066), while the secretion rate of K+, Na+, Cl-, Ca2+, total protein and α-amylase significantly increased(P < 0.01). The compound secretion rate of K+, Na+, Cl-, Ca2+, total protein and total phosphorus and α-amylase in parotid gland saliva increased(P < 0.01). The concentrations of Na+, Cl-, K+, total phosphorus, total protein and α-amylase in parotid were higher than those in submandibular gland (P < 0.01), and the concentration of Ca2+ in submandibular gland saliva was significantly higher than that in parotid (P < 0.001). CONCLUSION: The response of parotid to acid stimulation is stronger, and the secretion of submandibular gland is more stable. Acid stimulation significantly influences the concentrations of electrolytes in saliva, and the composited secretion rate is an evaluation index to reflect both flow rate and composition concentration of saliva. The parotid gland plays an important role in the secretion of total protein, total phosphorus and α-amylase in saliva, and the submandibular gland is the main source of Ca2+ in saliva.

[Establishment and application of new techniques for submandibular gland preservation].

The saliva secreted from submandibular gland (SMG) accounts for 60%-65%. It plays an important role in maintaining the human function of swallow, digestion, testing, speech, protection of oral mucosa, and prevention from dental carries. The SMG is frequently resected during the treatment for various kinds of oral and maxillofacial diseases, resulting in xerostomia and decreased quality of life. During the past 15 years, Research Center of Salivary Gland Diseases in Peking University School and Hospital of Stomatology conducted a series of studies on new techniques for preservation of SMG and achieved remarkable results. The clinicopathologic and imaging characteristics of IgG4-related sialadenitis (IgG4-RS) were clarified based on systematic studies. The results of studies on the pathogenesis of IgG4-RS showed that unbalance of inflammatory factors mediated the abnormality of secretion of SMG. IL-4 participates in occurring and development of glandular fibrosis of SMG. Regulation of tumor necrosis factor α (TNF-α) and cleaning of senescent cells might be taken as the targets for treatment of IgG4-RS. The combination of glucocorticoid and steroid-sparing agents showed effective results for treating IgG4-RS, clinical remission was achieved in all the patients, serum IgG4 levels decreased, and salivary gland secretion significantly increased. Sialoendoscopy-assisted sialolithectomy was applied in the treatment of about 1 000 cases with submandibular hilar calculi with a success rate of more than 90%. Transfer of SMG was used for prevention from radiation-induced xerostomia in the patients with head and neck carcinoma. SMG was transferred to the submental region before radiotherapy and was kept away from the ra-diation field. The results of prospective clinical controlled study showed this technique could effectively preserve the function of SMG and prevent from xerostomia. Based on the micro-anatomical study on the blood vessels and ducts of SMG, partial sialoadenectomy was applied for treatment of benign tumors in the SMG. A clinical controlled study confirmed its safety for control of the tumors and its advantage of preservation of SMG function. The studies on the involvement of SMG in oral squamous cell carcinoma (OSCC) provided the anatomical and histopathological basis for preservation of SMG during neck dissection for early cases with OSCC. A innovated surgical modality "four preservations including SMG" was used during the neck dissection for the early cases with OSCC. A prospective randomized clinical controlled study confirmed its safety, feasibility, effectiveness for control of the carcinoma, and advantages of preservation of SMG function.

[Clinicopathologic analysis of micro and mini parotid gland tumors].

OBJECTIVE: To investigate the clinicopathological characteristics of micro and mini parotid gland tumors and to provide reference for their clinical diagnosis and treatment. METHODS: Patients with parotid gland tumors treated in the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology from December 2012 to April 2020 were selected. Relevant clinical data of the patients with tumor diameter ≤20 mm detected by preoperative CT were collected to analyze the clinicopathological characteristics and prognosis of micro and mini parotid gland tumors. And the collected data were divided into two groups with diameter 11-20 mm and diameter ≤10 mm according to tumor diameter measured by preoperative CT. The clinicopathological differences between the two groups were statistically analyzed. RESULTS: A total of 2 067 patients with primary epithelial parotid gland tumors were collected, and 685 patients with tumor diameter ≤20 mm were examined by CT, accounting for 33.1%. The ratio of male to female patients with micro and mini parotid gland tumors was 1 ∶1.93, the average age was (45.3±13.8) years (12-83 years), and the median course of disease was 12 months (1 week to 30 years). Among them, 635 cases (92.7%) were benign tumors, 50 cases (7.3%) were malignant tumors, and the ratio of benign to malignant was 12.7 ∶1. The most common benign tumor was pleomorphic adenoma, and the most common malignant tumor was mucoepidermoid carcinoma. The micro and mini parotid gland tumors were divided into 11-20 mm group (n=611) and ≤10 mm group (n=74), the clinical characteristics comparison of the two groups of gender ratio, average age, course of di-sease had no statistical difference (P>0.05). In the 11-20 mm diameter group, the percentage of benign and malignant tumor was 92.8% (567/611) and 7.2% (44/611) respectively, and the ratio of benign to malignant tumors was 12.9 ∶1. In the ≤10 mm diameter group, the percentage of benign and malignant tumor was 91.9% (68/74) and 8.1% (6/74) respectively, and the ratio of benign to malignant tumors was 11.3 ∶1. There was no significant difference between the two groups (P>0.05). Fifty patients with malignant tumor were followed up for the median follow-up period of 39.5 months (1-91 months). Local recurrence occurred in 2 patients with one death. The overall 2-year survival rate was 93.7% and the 5-year survival rate was 89.3%. CONCLUSION: The majority of micro and mini parotid gland tumors was benign lesion. There was a good prognosis for micro and mini parotid gland carcinoma. Early surgical treatment was recommended for micro and mini parotid gland tumors.

[Clinical analysis of selective tracheostomy necessary for patients undergoing head and neck surgery with free flap reconstruction].

OBJECTIVE: To discover the factors that may affect the use of selective tracheostomy among patients who have undergone head and neck surgeries with free flap reconstruction, so that the patients will not need tracheostomy nor receive the unnecessary treatment. METHODS: Five hundred and thirty-three patients who had undergone head and neck surgery with free flap reconstruction operated by the same team of surgery at Department of Oral and Maxillofacial Surgery at Peking University School of Stomatology from 2015 to 2016 were reviewed. Three hundred and twenty-one (60.2%) of these patients underwent selective tracheostomy. All the patients' demographic information, operation-related information, prior treatments, comorbidities and complications were recorded and analyzed. RESULTS: The patients with defects of the tongue, mouth floor, oropharynx and bilateral mandible, who underwent neck dissection and with previous radiotherapy and smoking habit were more likely to get selective tracheostomy. Usage of bulky soft tissue flap might also add to the risk of airway obstruction and the need of selective tracheostomy, while other factors were not significantly related to the risk of postoperative airway obstruction and the patients could be kept safe without selective tracheostomy. Most cases without tracheostomy were kept safe except one case, while 8.39% of the patients with tracheostomy suffered from tracheostomy related complications, mainly pneumonia and hemorrhage of the tracheostomy wound, yet none led to serious consequences or even death. CONCLUSION: Selective tracheostomy is not necessary for patients who have undergone head and neck surgeries with free flap reconstruction except that there are defects at the tongue, oropharynx and mandible. Neck dissection, bulky soft tissue flap reconstruction, previous radiotherapy and smoking habit may also add to the risk of postoperative airway obstruction, while a favorable decision would involve a combination of all the above factors to assure the safety of the postoperative airway for the patients undergone head and neck surgeries with free flap reconstruction.

[Studies on newly recognized chronic sialadenitis].

Some kinds of chronic sialadenitis were recognized during the recent years. They have specific pathogenesis, clinical and histopathologic appearances, and require specific treatment. IgG4-related sialadenitis (IgG4-RS) is one of the immune-mediated diseases, characterized by tumefactive lesions. The incidence of IgG4-RS obviously increased during the past 30 years. The study on the potential relationship between occupational exposure to chemical substances and the incidence of IgG4-RS showed that subjects with occupational exposure to agents known to cause IgG4-RD had an increased risk for IgG4-RS. Surgical excision of involved SMG could not control the disease progression, which is not recommended for treatment of IgG4-RS. The combination of glucocorticoid and steroid-sparing agents is effective for treating IgG4-RS, and restores salivary gland function. Radioiodine induced sialadenitis (RAIS) is one of the common complications of postoperative adjuvant treatment of differentiated thyroid cancer by 131I. The incidence of the disease is related to radiation dosage. Clinically, the patients suffered from swelling and tenderness in the buccal or submandibular regions, especially during the mealtime. Imaging appearances are similar to those of chronic obstructive sialadenitis. Conservative managements, such as gland massage, sialagogues, are the mainstream methods in the treatment of RAIS. Sialendoscopy is feasible for RAIS, but not as effective as conventional obstructive sialadenitis (COS). Therefore the prevention of RAIS is crucial. Eosinophilic sialodochitis (ES) is a new type of chronic inflammatory disease of the salivary gland related to allergy. It has characteristics of swelling of multiple major salivary glands, strip-like gelatinous plugs discharged from the duct orifice of the gland, elevated level of serum IgE and eosinophils in peripheral blood, infiltration of eosinophils and IgE positive plasma cells in the tissues, allergic history, increased expression of allergy-related cytokines, such as IL-4, IL-5, IL-13, and eotaxin, which suggest allergic reactions as a potential pathogenesis of the disease. The clinical, laboratory, histological, and immunohistochemical characteristics of ES are significantly different from conventional obstructive sialadenitis (COS). Therefore, it is suitable to separate ES from COS. Conservative managements, such as self-maintenance therapy and anti- allergic modality are the choices of treatment for ES. Based on the results of our comprehensive studies a new classification of chronic sialadenitis is suggested.

[Effect of topical injection of cyclosporine A on saliva secretion and inflammation in the submandibular gland of non-obese diabetic mice].

OBJECTIVE: To investigate the effects of topical administration of cyclosporine A (CsA) on salivary secretion and inflammation of the submandibular glands in non-obese diabetic (NOD) mice. METHODS: Female NOD mice, 21 aged 14 weeks and 18 aged 21 weeks were selected and randomly divided into low-dose group, high-dose group and control group on average. CsA was injected into submandibular glands. One week later the saliva stimulated by pilocarpine was collected and measured. The submandibular glands were collected to make paraffin sections. The lymphocyte infiltration in submandi-bular gland was observed by microscope after hematoxylin-eosin (HE) staining. The number of lymphocyte infiltration foci was counted to calculate the focus sore and the ratio of lymphocyte infiltration area to total gland area was figured up by Leica image analysis system. The expressions of inflammatory cytokines tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), interleukin-4 (IL-4), IL-13, IL-17F, IL22 and IL-23a in the submandibular glands of the NOD mice were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Cell apoptosis in the submandibular gland was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL). The levels of serum creatinine (Scr), blood urea nitrogen (BUN), uric acid (UA), alanine aminotransferase (ALT), aspertate aminotransferase (AST), alkaline phosphatase (ALP), albumin (ALB) and γ-glutamyl transferase (GGT) were measured by automatic biochemical analyzer to evaluate liver and kidney functions. RESULTS: After topical injection of CsA in the submandibular gland, the stimulated salivary flow rate of the 14- and 21-week-old NOD mice significantly increased compared with the control group (P < 0.01 or P < 0.05), and the number and area of lymphocyte infiltration foci in the 14-week-old NOD mice low-dose group significantly decreased compared with the control group (P < 0.01). Low and high dose of CsA had similar effects on reducing inflammation and improving salivary secretion. The overall level of inflammatory cytokines in the submandibular gland did not decrease significantly. The number of cell apoptosis of submandibular gland in the NOD mice treated with CsA decreased compared with the control group, but there was no statistically significant difference. Topical injection of CsA had no adverse effect on liver and kidney function in the NOD mice. CONCLUSION: Topical injection of CsA can reduce lymphocyte infiltration in submandibular gland of NOD mice and improve salivary secretion.

[The effect of visualized saphenous nerve block through minimally invasive far medial-subvastus approach on the analgesia after total knee arthroplasty].

Objective: To report a method of visualized saphenous nerve block (VSNB) through minimally invasive far medial-subvastus approach distal to the adductor canal in total knee arthroplasty (TKA), and investigate the effect of VSNB in this way on postoperative pain relief. Methods: A total of 100 patients with knee osteoarthritis were prospectively included from June 2018 to October 2019, 29 males and 71 females, aged 50-87(70±8) years. All patients undergoing TKA through minimally invasive far medial-subvastus approach were randomized to visualized saphenous nerve block combined with periarticular infiltration analgesia group (Group VSNB+PIA) or only periarticular infiltration analgesia group (Group PIA),50 cases in each group. The visual analogue scale (VAS) was used to evaluate the pain degree of patients. Furthermore, the scores of VAS in resting and active state at 4, 8, 12, 24, 48, 72 hours after operation and the proportion of patients receiving parecoxib within 72 hours after operation were compared between the two groups. Results: There was statistically significant difference between the two groups in terms of VAS scores in resting state after surgery(F=15.295,P<0.05).The postoperative VAS scores of Group VSNB+PIA at 4, 8, 12, 24 hours at resting state were 1.3±0.8, 1.4±0.7, 1.7±0.8, 3.1±0.8 respectively, which were all significantly lower than those of Group PIA (1.6±0.9, 1.8±0.8, 2.3±0.9, 3.6±0.8) (P<0.05). The overall difference in terms of VAS scores at active state after surgery was statistically significant between the two groups(F=18.532, P<0.05). The postoperative VAS scores of Group VSNB+PIA at 4, 8, 12, 24 hours at active state were 2.0±0.8, 2.2±0.7, 2.7±0.6, 3.7±0.7 respectively, which were all significantly lower than those of Group PIA (2.3±0.8, 2.7±0.7, 3.3±0.8, 4.4±0.7)(P<0.05). Fourteen percent of patients (7/50) in VSNB+PIA group accepted parecoxib within 72 hours after surgery, which was significantly lower than that in PIA group (34%, 17/50) (P<0.05). Conclusions: It is easy to expose the saphenous nerve beyond the adductor canal through minimally invasive far medial-subvastus approach. The Combination therapy of VSNB+PIA is more effective than the simple per-articular infiltration analgesia in providing pain relief after total knee arthroplasty.

[Short-term efficacy of endoscope assisted arthroplasty for total hip replacement via a minimum invasive direct anterior approach].

Objective: To present the surgical technique of endoscope assisted arthroplasty for total hip replacement via minimum invasive direct anterior approach and analyze its early clinical outcome. Methods: From November 2019 to May 2020, endoscopic total hip arthroplasty via direct anterior approach was performed on 30 patients (32 hips), including 12 males (13 hips) and 18 females (19hips), in the Department of Orthopedics of Fujian Provincial Hospital. The average age of patients was (63±14) years (ranged 32-87 years). The average body mass index (BMI) of the patients was (26.9±4.5) kg/m2. There were 12 cases whose BMI was higher than 28.0 kg/m2 and the maximum BMI was 35.2 kg/m2. The surgery was performed on supine position using a 5-6 cm proximal transverse incision and a distal selective percutaneous puncture incision to perform the acetabulum preparation and the prosthesis implantation with the novel designed split tool under the monitoring of endoscope; the lift-top tractor system was used to raise the femur in the transverse incision for femoral side preparation and prosthesis implantation. Relevant data such as the perioperative status, operation time, postoperative pain score assessed with visual analogue score (VAS), prosthesis position, joint function, lateral femoral cutaneous nerve function and patient satisfaction were recorded to analyze the short-term efficacy. Results: The average length of incision of the 30 cases(32 hips)was (5.9±0.4) cm. All patients in this study had I/A wound healing with no perioperative complications such as infection, poor wound healing and fractures of the proximal femur. The average operation time was (65±14) min, and the average amount of blood loss was (136±56) ml. The average acetabular abduction angle and acetabular antegrade inclinations was 41.4°±3.6° and 16.0°±5.3°, respectively. The resting-state VAS of pain at 6 h and 24 h after operation were all ≤2, and there was no significant difference between the VAS scores after exercise and the VAS scores at the resting state (both P>0.05). There was no statistically significant difference between the VAS scores at the same state at different times (both>0.05). The weight-bearing exercise was applied in all patients within 12 h after surgery. The length of postoperative hospital stays varied from 1 to 3 days((2.0±0.9) days). At the 6th-month follow-up, the Harris score of the hip was 94.7±3.0, which significantly improved when compared with that before the operation (35.5±8.1)(P<0.01). No sensory abnormalities were observed. The satisfaction score of the patients was 9.3±0.5 (full score set to 10). Conclusions: The efficacy and safety of the endoscope assisted total hip arthroplasty for total hip replacement is acceptable. This procedure can help to reduce the compression of the muscles by the retractor in the conventional operation. It can be applied to obese and muscular patients.

[Twelve-week of sofosbuvir/velpatasvir therapeutic regimen for chronic hepatitis C patients in northwest region of China: a real-world multicenter clinical study].

Objective: To study the real-world outcome of China FDA-approved Sofosbuvir (SOF)/Velpatasvir (VEL) in Northwest China. Methods: In this multicenter, prospective, real-world cohort study, we recruited patients from 10 sites from Northwest China, who were chronically infected with HCV GTs 1-6 from 06/2018 to 09/2019. Patients received SOF (400mg)/VEL (100mg) for 12 weeks, and with ribavirin 900-1200 mg for GT3 cirrhosis and for any genotype decompensated cirrhosis. The primary endpoint was sustained virological response at 12-weeks post-treatment (SVR12) and safety. The secondary endpoint was the change of liver function after the achievement of SVR12. Results: Totally, 143 patients were enrolled in the study, four patients were lost to follow-up and one died during the follow-up, 138 patients were included in per-protocol analysis. Of the 138 patients, the mean age 53 years, 53.6% male, 94.2% Han nationality, 53.6% liver cirrhosis, 10.1% HBsAg(+), 6.5% renal dysfunction, 5.1% treatment-experienced, and 16.7% patients received ribavirin treatment. The genotype distribution was as follows: 35.5% GT1, 42.8% GT2, 15.9% GT3, and 5.8% un-typed. The SVR12 rate was 96.5% (138/143, 95%CI: 93.5%-99.6%) for intention-to-treat analysis, and in per-protocol analysis, all 138 patients obtained SVR12 (100%). Compared with baseline, the serum total bilirubin, ALT and AFP levels decreased (all P < 0.05), as well as increased ALB and platelet count (all P < 0.001) at post-treatment 12-weeks. Overall adverse events (AEs) rate is 29.0%, and the most common AEs were anemia (14.5%) and fatigue (8.0%). Severe side effects (edema and fatigue) occurred in 2 patients, one of whom needed a short-term interruption of treatment due to fatigue. Conclusion: In this real-world cohort study, 12-week SOF/VEL regimen with or without ribavirin achieved high SVR12 rates (96.5%-100% overall) with excellent safety profile among patients with HCV GT1/2/3 infection including patients with GT3 and cirrhosis, and led to improvement of liver function.

Retrospective study of the functional and oncological outcomes of conformal sphincter preservation operation in the treatment of very low rectal cancer.

BACKGROUND: Conformal sphincter preservation operation (CSPO) is a new surgical procedure for very low rectal cancers (within 4-5 cm from the anal verge). CSPO preserves more of the dentate line and distal rectal wall and also avoids injuring nerves in the intersphincteric space, resulting in satisfactory anal function after resection. The aim of this study was to analyze the short-term surgical results and long-term oncological and functional outcomes of CSPO. METHODS: Consecutive patients with very low rectal cancer, who had CSPO between January 2011 and October 2018 at Changhai Hospital, Shanghai were included. Patient demographics, clinicopathological features, oncological outcomes and anal function were analyzed. RESULTS: A total of 102 patients (67 men) with a mean age of 56.9 ± 10.8 years were included. The median distance of the tumor from the anal verge was 3 (IQR, 3-4) cm. Thirty-five patients received neoadjuvant chemoradiation (nCRT). The median distal resection margin (DRM) was 0.5 (IQR, 0.3-0.8) cm. One patient had a positive DRM. All circumferential margins were negative. There was no perioperative mortality. The postoperative complication rate was 19.6%. The median duration of follow-up was 28 (IQR, 12-45.5) months. The local recurrence rate was 2% and distant metastasis rate was 10.8%. The 3-year overall survival and disease-free survival rates were 100% and 83.9%, respectively. The mean Wexner incontinence and low anterior resection syndrome scores 12 months after ileostomy reversal were 5.9 ± 4.3, and 29.2 ± 6.9, respectively. CONCLUSIONS: For patients with very low rectal cancers, fecal continence can be preserved with CSPO without compromising oncological results.

[Measurement of the weight and volume of submandibular gland in vitro].

OBJECTIVE: To measure the weight and volume of normal submandibular gland by in vitro detection of glandular body, to compare with the measurement values of CT volume rendering to evaluate the consistency of the two methods, and to explore the related factors affecting the weight and volume of the submandibular gland. METHODS: The patients who underwent neck dissection due to oral cancer and were confirmed with normal submandibular gland by postoperative histopathology in Peking University School and Hospital of Stomatology from May 2019 to January 2020 were collected in this study and divi-ded into 4 groups according to the age standards raised by the Society of Geriatrics Chinese Medical Association and WHO (2000) age standards. The submandibular gland was carefully dissected along with the capsule immediately after neck dissection. The weight and volume of submandibular gland were accurately measured by an integrated aseptic measuring device. The volume of submandibular gland was measured by CT volume rendering before operation and the consistency of the two methods was evaluated. The 95% confidence interval of the weight and volume of submandibular gland in the different groups of Chinese people, which were divided by gender and age, were calculated, and the correlation with age, gender, height, weight, body mass index (BMI) and other factors was analyzed. RESULTS: The weight and vo-lume of submandibular gland were measured in 220 subjects. The average weight and volume of submandibular gland were (11.69±2.45) g and (11.55±2.41) cm3 respectively. The volume of submandibular gland measured by CT volume rendering ranged from 70% to 82% of that measured by in vitro detection of glandular body, and the correlation coefficient between the two methods was 0.976 (P < 0.05). The gender difference of weight and volume of submandibular gland existed in the groups of youth, middle-aged, young elderly and elderly groups, the values of males were obviously higher than those of females (P < 0.05). There was no gender difference of weight and volume of submandibular gland in the adolescent group (P > 0.05). The weight and volume of submandibular gland had a strong positive correlation with body height (P < 0.05), a weak positive correlation with body weight (P < 0.05), and no correlation with BMI (P > 0.05). The female's weight and volume of submandibular gland in the young elderly and elderly groups were significantly lower than those in the other three groups (P < 0.05). CONCLUSION: The normal reference range of the weight and volume of submandibular gland in vitro were established in different age and gender groups of Chinese people. The volume of submandibular gland mea-sured by CT volume rendering was 70%-82% of that measured by in vitro detection of glandular body. The results of the two methods had a high degree of consistency. The weight and volume of submandibular gland were related to age, gender, body height and body weight.

[Inflammation grading and sialoendoscopic treatment of 131I radioiodine-induced sialadenitis].

OBJECTIVE: To investigate the inflammation grading of 131I radioiodine-induced sialadenitis based upon sialoendoscopic and sialographic appearances, and to evaluate the results of sialoendoscopic intervention. METHODS: The patients diagnosed with 131I radioiodine-induced sialadenitis and underwent sialoendoscopic exploration and intervention procedures in Peking University Hospital of Stomatology from Nov. 2012 to Oct. 2018 were included in this study. The appearances of sialogaphy and sialoendoscopy were analyzed and classified. The treatment options included irrigation with saline and dexamethasone and mechanical dilatation by sialoendoscope. The patients were followed up after treatment. RESULTS: Forty-two patients with 131I radioiodine-induced sialadenitis were included. There were 5 males and 37 females, with a male-to-female ratio of 1 ∶7.4. Symptoms included recurrent swelling and pain in the parotid glands, and dry mouth. Sialography showed stenosis in the main duct,and in some cases nonvisua-lization of the branches. Sialoendoscopy showed narrowing of the main duct, and the branch duct atresia was seen. The appearances of sialogaphy and sialoendoscopy were analyzed and classified into 3 groups: (1) Mild inflammation: stenosis and ectasia occurred in the main duct, whereas the 0.9 mm sialoendoscope could pass through easily. (2) Moderate inflammation: one point of severe stricture could be seen in the main duct where 0.9 mm sialoendoscope could not be passed through. (3) Severe inflammation: two points or more of severe strictures or diffused strictures occurred in the main duct. Thirty-three patients with 65 affected glands were examined by both sialography and sialoendoscopy. Eight glands were classified as mild inflammation, 23 glands moderate inflammation, and 34 glands severe inflammation. The duration of follow-up ranged from 3-72 months. The clinical results were evaluated as good in 22 glands, fair in 22 glands, and poor in 19 glands, with an overall effective rate of 69.8% (44/63). CONCLUSION: The clinical, sialographic and sialoendoscopic appearances of 131I radioiodine-induced sialadenitis showed their characteristics. We proposed an inflammation grading standard for the 131I radioiodine-induced sialadenitis based on the appearances of sialography and sialoendoscopy. Sialoendoscopy can significantly alleviate the clinical symptoms, which is an effective therapy, and better for early lesions.

Difference in the frequency of pouchitis between ulcerative colitis and familial adenomatous polyposis: is the explanation in peripouch fat?

AIM: Patients with ulcerative colitis (UC) have an unexplained higher incidence of pouchitis and a greater amount of peripouch fat compared with patients with familial adenomatous polyposis (FAP). The aims of this study were to compare the peripouch fat areas between patients with UC and patients with FAP, and to explore relationship between peripouch fat and pouchitis or chronic antibiotic-refractory pouchitis (CARP). METHOD: Patients with an abdominal CT image from our prospectively maintained Pouch Database were included. Abdominal fat and peripouch fat were measured on CT images at different levels or planes. Comparisons of peripouch fat and CARP were performed before and after propensity score matching. RESULTS: A total of 277 patients with UC and 40 patients with FAP were included. Compared with patients with FAP, patients with UC were found to have a higher incidence of pouchitis (58.5% vs 15.0%, P < 0.001) and CARP (24.5% vs 2.5%, P = 0.002) and a higher total peripouch fat area (P = 0.030) and mesenteric peripouch fat area (P = 0.022) at Level-3. Univariate and multivariate analyses showed that diagnosis (UC vs FAP) and peripouch fat areas at Level-3 and Level-5 were independent risk factors for CARP. With propensity score matching, 38 pairs of patients with UC and FAP were matched successfully. After matching, patients with UC were found to have higher total peripouch fat area and higher mesenteric peripouch fat area at Level-3, and a higher incidence of pouchitis (57.9% vs 13.2%, P < 0.001) and CARP (23.7% vs 2.6%, P = 0.007). CONCLUSION: Our study demonstrates that patients with UC have more peripouch fat than those with FAP, which may explain the difference in the frequency of pouchitis and CARP between these groups of patients.

[Clinicopathological features and possible prognostic factors in parotid lymphomas].

OBJECTIVE: To investigate the clinicopathological features and prognostic factors in lymphoma of parotid origin. METHODS: Clinicopathological data of the patients with parotid lymphoma who were initially diagnosed in Peking University Hospital of Stomatology from 2006 to 2016 were collected and analyzed retrospectively. The patients were followed-up for 5 to 149 months with a median period of 45 months, and the factors influencing the prognosis were evaluated. RESULTS: A total of 41 patients with primary parotid lymphoma were included in this retrospective study. The rate of male to female was 1:2.15. The median age was 57 years (ranging from 8 months to 91 years). According to WHO classification, 40 cases (97.1%) were diagnosed as non-Hodgkin lymphoma (NHL), including 15 cases of extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT), 14 cases of diffuse large B cell lymphoma (DLBCL) as well as 4 cases of follicular lymphoma, while other subtypes of NHL were rare. Only one case was diagnosed as Hodgkin lymphoma. Regarding the clinical staging at the initial diagnosis, 37 patients (90.2%) were diagnosed as stage IE or IIE of the disease, while 4 patients (9.8%) as stage IIIE or stage IVE. Seven patients (17.1%) had a history of Sjögren syndrome (SS), all of whom were MALT lymphoma. The mean ill duration of the 41 patients were 20.7 months. Thirty-two patients (78%) presented a slowly growing painless mass in the parotid gland. Treatment options included localized therapy and systemic therapy, all of whom had good curative effect. Nine patients (21.9%) died during the follow-up period. The overall survival rates of 2-year and 5-year were 84.5% and 81.3% respectively. The univariate analysis demonstrated statistically significant differences for accelerated growth of tumor (P=0.005), and presence of tumor capsule (P=0.011). The multi-univariate analysis demonstrated statistically significant differences for presence of tumor capsule (P=0.041). CONCLUSION: A large majority of primary parotid lymphoma were NHL, among which MALT lymphoma and DLBCL were common subtypes. Most patients presented an indolent mass in parotid gland, which should be distinguished from the parotid benign tumors. SS is closely related to the pathogenesis of MALT lymphoma. The prognosis is better than that of other malignant parotid tumors. Absence of tumor capsule may predict a poor prognosis in patients with parotid lymphoma.

[Role and mechanism of muscarinic acetylcholine receptor in the regulation of submandibular gland secretion].

Muscarinic acetylcholine receptors (mAChRs), including M1-M5 subtypes, are classic receptors in regulating water, ion, and solute transport in salivary gland. Our work focuses on the studies on the expression pattern and function of mAChR in the submandibular gland (SMG), and the underlying mechanism involved in the mAChR-regulated secretion, together with the effect of parasympathectomy on the salivary secretion. Microvascular autotransplantation of SMG into the temporal fossa provides a continuous and endogenous source of fluids, and is currently an effective method for treating severe keratoconjunctivitis sicca. By using RT-PCR, Western blotting, and immunofluorescence, our data demonstrated that the expression of M1 and M3 subtypes were decreased in latent period in rabbit SMG autotransplantation model, whereas carbachol stimulation promoted the salivary secretion, as well as M1 and M3 expressions. By contrast, mAChRs were hypersensitive in epiphora SMGs, whereas atropine gel and botulinum toxin A application significantly inhibited the hypersecretion in both animal models and patients. Furthermore, the possible intracellular signal molecules involved in the mAChR-modulated salivary secretion were explored. Activation of mAChR upregulated the expression of aquaporin 5 (AQP5), the main transporter that mediated water secretion through transcellular pathway, and led to AQP5 trafficking from lipid rafts to non-lipid microdomain. Extracellular signal-regulated kinase 1/2 (ERK1/2) was involved in the mAChR-regulated AQP5 content. mAChR activation also modulated the expression, distribution, and function of tight junction proteins, and increased paracellular permeability. ERK1/2/ß-arrestin2/clathrin/ubiquitin signaling pathway was responsible for the mAChR-regulated downregulation of tight junction molecule claudin-4. Cytoskeleton filamentous actin (F-actin) was also involved in the distribution and barrier function of epithelial tight junctions. Besides, endothelial tight junctions were opened by mAChR agonist-evoked salivation in the mice. Furthermore, parasympathetic denervation increased resting salivary secretion in the long terminrats and minipigs. Taken together, our work demonstrated that mAChR regulated saliva secretion via transcellular and paracellular pathways in SMG epithelium as well as tight junction opening in SMG endothelium. Modulation of mAChR might be a promising strategy to ameliorate SMG dysfunction.

[Clinicopathological characteristics and diagnosis of IgG4related sialadenitis].

Immunoglobulin G4-related sialadenitis (IgG4-RS) is a newly recognized immune-mediated disease and one of immunoglobulin G4-related diseases (IgG4-RD). Our multidisciplinary research group investigated the clinicopathological characteristics and diagnosis of IgG4-RS during the past 10 years. Clinically, it showed multiple bilateral enlargement of major salivary glands (including sublingual and accessory parotid glands) and lacrimal glands. The comorbid diseases of head and neck region including rhinosinusitis, allergic rhinitis, and lymphadenopathy were commonly seen, which could occur more early than enlargement of major salivary glands. Internal organ involvements, such as autoimmune pancreatitis, sclerosing cholangitis, and interstitial pneumonia could also be seen. Thirty-five (38.5%) patients had the symptom of xerostomia. Saliva flow at rest was lower than normal. Secretory function was reduced more severely in the submandibular glands than in the parotid glands. Serum levels of IgG4 were elevated in almost all the cases and the majority of the patients had increased IgE levels. CT, ultrasonography, and sialography showed their imaging characteristics. Histologically it showed marked lymphoplasmacytic inflammation, large irregular lymphoid follicles with expanded germinal centers, prominent cellular interlobular fibrosis, eosinophil infiltration, and obliterative phlebitis. Their immunohistological examination showed marked IgG-positive and IgG4-positive plasma cell infiltration and high IgG4/IgG ratio. The disease could be divided into three stages according to severity of glandular fibrosis. The serum IgG4 level was higher and the saliva secretion lower as glandular fibrosis increased. IgG4-RS should be differentiated from other diseases with enlargement of major salivary gland and lacrimal gland, such as primary Sjögren syndrome, chronic obstructive submandibular sialadenitis, and eosinophilic hyperplastic lymphogranuloma.

[A 20-year study on microvascular autologous transplantation of submandibular gland for treatment of severe dry eye].

Severe dry eye is a refractory ophthalmologic disease. Our multidisciplinary research group treated severe dry eye by microvascular autologous transplantation of submandibular gland (SMG) during the past 20 years. The SMG, with its blood vessels and Wharton's duct, was harvested from the submandibular triangle and transferred to the temporal area. The blood vessels in the SMG were anastomosed with the temporal blood vessels using a microsurgical technique. Then, the distal end of Wharton's duct was sutured to form an opening in the upper lateral conjunctival fold. The tear was replaced by the secretion of the transplanted SMG to lubricate the ocular surface. In our study, the surgical techniques of blood vessel management were continuously modified to increase the survival rate of the transplanted SMG. A novel surgical modality of partial transplantation of SMG was established to prevent postoperative epiphora. A clinical study with the largest case number in the world was conducted and the effectiveness of transplantation of SMG for severe dry eye was fully confirmed. In order to resolve two main clinical problems including ductal obstruction resulted from low secretion rate during the latent period, and epiphora due to over secretion of the transplanted SMG in the later term of transplantation, the regulation of the secretion mechanism of the normal and transplanted SMG were investigated. New opinions on mechanisms of saliva secretion were provided. Based on the priniciple of translational medicine, the results of related basic research were applied in the clinic. The clinical guidelines for secretion regulation of transplanted SMG were established. A concept of chronic obstructive sialadenitis of transplanted SMG was provided and its diagnostic criteria, diagnostic technique of sialography, and therapeutic regimen were established. As a result, the surgical success rate was obviously elevated, the surgical complications were decreased, and life quality of the patients was greatly improved.