Treatment response assessment to chemotherapy with bevacizumab for colorectal liver metastasis by contrast-enhanced ultrasound.

Background: Though contrast-enhanced ultrasound (CEUS) perfusion parameters have been approved to be potential indicators for response to chemotherapy in solid tumors, their ability in assessment of colorectal liver metastasis (CRLM) to chemotherapy with bevacizumab (Bev) has rarely been investigated. Methods: From March 2021 to May 2022, 115 consecutive CRLM patients with CEUS pre- and post-2 months' chemotherapy with Bev were prospectively enrolled. One target lesion per patient underwent CEUS quantitative analysis with SonoLiver software. Rise time, time-to-peak, mean transit time, maximal intensity (IMAX), and area under the time-intensity curve (AUC) were assessed with region of interest (ROI) selected on whole lesion, lesion periphery, and internal lesion, respectively. The reduction and ratio of post- to pre-treatment in parameters were investigated in development cohort (n=89) and validated in internal validation cohort (n=26) according to the chronological order. Results: With modified Response Evaluation Criteria in Solid Tumor as reference, 48, 14 responders and 41, 12 non-responders were included in development and validation cohort, respectively. Significantly smaller values of IMAX and AUC on ROIwhole, ROIperipheral, and ROIinternal, were observed post-treatment in development cohort (all P<0.05). In predicting treatment response, the influence of ROI selection was observed when using ∆IMAX and ∆AUC, while no influence was observed using ratios. Areas under the receiver operating characteristic curve (AUROCs) for ∆IMAX and ∆AUC on ROIperipheral were 0.939 (0.867-0.979), 0.951 (0.883-0.985), and 0.917 (0.740-0.988), 0.923 (0.748-0.990) in development and validation cohort, respectively. For ratios of IMAX and AUC, AUROCs were 0.976 (0.919-0.997), 0.938 (0.865-0.978), and 0.899 (0.717-0.982), 0.982 (0.836-1.000) in development and validation cohort, respectively. Conclusions: IMAX and AUC showed significant reductions in responders, and different analyses ROIs influence the performance of ∆IMAX and ∆AUC in response assessment. Parameters derived from ROI peripheral exhibited the most promising results in predicting treatment response.

Oceanic non-Kolmogorov optical turbulence and spherical wave propagation.

Light propagation in turbulent media is conventionally studied with the help of the spatio-temporal power spectra of the refractive index fluctuations. In particular, for natural water turbulence several models for the spatial power spectra have been developed based on the classic, Kolmogorov postulates. However, as currently widely accepted, non-Kolmogorov turbulent regime is also common in the stratified flow fields, as suggested by recent developments in atmospheric optics. Until now all the models developed for the non-Kolmogorov optical turbulence were pertinent to atmospheric research and, hence, involved only one advected scalar, e.g., temperature. We generalize the oceanic spatial power spectrum, based on two advected scalars, temperature and salinity concentration, to the non-Kolmogorov turbulence regime, with the help of the so-called "Upper-Bound Limitation" and by adopting the concept of spectral correlation of two advected scalars. The proposed power spectrum can handle general non-Kolmogorov, anisotropic turbulence but reduces to Kolmogorov, isotropic case if the power law exponents of temperature and salinity are set to 11/3 and anisotropy coefficient is set to unity. To show the application of the new spectrum, we derive the expression for the second-order mutual coherence function of a spherical wave and examine its coherence radius (in both scalar and vector forms) to characterize the turbulent disturbance. Our numerical calculations show that the statistics of the spherical wave vary substantially with temperature and salinity non-Kolmogorov power law exponents and temperature-salinity spectral correlation coefficient. The introduced spectrum is envisioned to become of significance for theoretical analysis and experimental measurements of non-classic natural water double-diffusion turbulent regimes.

Antihyperuricemic and nephroprotective effects of extracts from Orthosiphon stamineus in hyperuricemic mice.

OBJECTIVES: To investigate the antihyperuricemia and nephroprotective effects of Orthosiphon stamineus extracts on hyperuricemia (HUA) mice and explore the potential mechanisms. METHODS: Orthosiphon stamineus extracts were extracted using 50% ethanol and enriched using ethyl acetate, and characterised utilising UPLC/ESI-MS. A potassium oxonate (PO) induced hyperuricemic mouse model was used to evaluate antihyperuricemia and nephroprotective effects of O. stamineus ethyl acetate extracts (OSE). KEY FINDINGS: Eight constituents from OSE were identified and OSE treatment ameliorated HUA by regulating key indicators of kidney dysfunction and xanthine oxidase, adenosine deaminase activity and urate transporters in hyperuricemic mice. Moreover, in renal histopathology analysis, OSE significantly alleviated kidney injury. CONCLUSIONS: These findings demonstrate that OSE has antihyperuricemic and nephroprotective effects on PO-induced HUA mice and those results indicate that OSE could be a safe and effective agent or functional ingredient for treating HUA.

Carthamin yellow inhibits matrix degradation and inflammation induced by LPS in the intervertebral disc via suppression of MAPK pathway activation.

Carthamin yellow (CY), which is a flavonoid compound isolated from safflower, has various pharmacological effects including promoting blood circulation to remove blood stasis and alleviating pain. CY is a herb used in Chinese traditional medicines. Intervertebral disc degeneration (IDD) is a common spinal disorder and degeneration of nucleus pulposus (NP) cells and inflammation are significant parts of the pathological cascade. The curative effect of CY on NP cells in association with degeneration and inflammation remains to be elucidated. In the present study, rat NP cells were isolated, cultured and used to detect the suppressive effects of CY on lipopolysaccharide (LPS)-induced genetic expression variation and the expression of matrix degradation enzymes, including matrix metallopeptidase-3, ADAM metallopeptidase with thrombospondin type 1 motif (ADAMTS)-4 and ADAMTS-5. A protective effect of CY on NP cells was observed against LPS-induced matrix degradation and inflammation. Western blotting results demonstrated that pretreatment with CY significantly suppressed the LPS-induced activation of the mitogen activated protein kinase (MAPK) pathway. The results of the present study suggested that CY exerted anti-degenerative and anti-inflammatory effects on NP cells via inhibition of MAPK pathway activation. Therefore, CY may be a potential therapeutic drug for the treatment of IDD in the future.

Neurokinin-1 Receptor-Immunopositive Neurons in the Medullary Dorsal Horn Provide Collateral Axons to both the Thalamus and Parabrachial Nucleus in Rats.

It has been suggested that the trigemino-thalamic and trigemino-parabrachial projection neurons in the medullary dorsal horn (MDH) are highly implicated in the sensory-discriminative and emotional/affective aspects of orofacial pain, respectively. In previous studies, some neurons were reported to send projections to both the thalamus and parabrachial nucleus by way of collaterals in the MDH. However, little is known about the chemoarchitecture of this group of neurons. Thus, in the present study, we determined whether the neurokinin-1 (NK-1) receptor, which is crucial for primary orofacial pain signaling, was expressed in MDH neurons co-innervating the thalamus and parabrachial nucleus. Vesicular glutamate transporter 2 (VGLUT2) mRNA, a biomarker for the subgroup of glutamatergic neurons closely related to pain sensation, was assessed in trigemino-parabrachial projection neurons in the MDH. After stereotactic injection of fluorogold (FG) and cholera toxin subunit B (CTB) into the ventral posteromedial thalamic nucleus (VPM) and parabrachial nucleus (PBN), respectively, triple labeling with fluorescence dyes for FG, CTB and NK-1 receptor (NK-1R) revealed that approximately 76 % of the total FG/CTB dually labeled neurons were detected as NK-1R-immunopositive, and more than 94 % of the triple-labeled neurons were distributed in lamina I. In addition, by FG retrograde tract-tracing combined with fluorescence in situ hybridization (FISH) for VGLUT2 mRNA, 54, 48 and 70 % of FG-labeled neurons in laminae I, II and III, respectively, of the MDH co-expressed FG and VGLUT2 mRNA. Thus, most of the MDH neurons co-innervating the thalamus and PBN were glutamatergic. Most MDH neurons providing the collateral axons to both the thalamus and parabrachial nucleus in rats were NK-1R-immunopositive and expressed VGLUT2 mRNA. NK-1R and VGLUT2 in MDH neurons may be involved in both sensory-discriminative and emotional/affective aspects of orofacial pain processing.

[Physico-chemical Characteristics of Individual Aerosol Particles in Marine Atmosphere on South Hemisphere].

During the 29th Chinese National Antarctic Research Expedition (CHIANRE), individual particle samples were collected from South China to Antarctic during November 2012 to April 2013. A transmission electron microscopy with energy-dispersive X-ray spectrometry (TEM-EDS) was employed to analyze the morphology, mixing state, composition, and relative abundances of individual aerosol particles. Atmospheric particles were classified into four types:sea salt, mineral, S-rich and C-rich. Sea salt aerosols (SSA) were dominant in the marine particles from South China to Antarctic, and they were further divided into three sub-types:fresh SSA, partially aged SSA, and fully aged SSA. Partially and fully aged SSA accounted for 86% of total SSA number. Interestingly, surface of partially aged SSA and fully aged SSA contained abundant rod-like Na2SO4. Mineral dust particles increased in the coastal areas which were influenced by continental air. In addition, we found that S-rich particles were abundant at two sampling sites (the middle eastern of Indian Ocean and Antarctic inland). The back trajectories of air masses indicated that these S-rich particles were mainly formed via the oxidation of dimethyl sulfide (DMS) emitted from the marine phytoplanktons. Our study suggests that the SSA aging process in the South Hemisphere atmosphere was controlled by the DMS which is different from the SSA aging under the influence of anthropogenic pollutants in the North Hemisphere.

Endoscopic submucosal dissection versus transanal local excision for rectal carcinoid: a comparative study.

AIM: The aim of this study is to compare the short-term clinical outcomes between endoscopic submucosal dissection and transanal local excision for rectal carcinoid tumors. METHODS: Between 2007 and 2012, 31 patients with rectal carcinoid underwent endoscopic submucosal dissection at our hospital. They were compared with a matched cohort of 23 patients who underwent transanal local excision for rectal carcinoid between 2007 and 2012. Short-term clinical outcomes including surgical parameters, postoperative recovery, and oncologic outcomes were compared between the two groups. RESULTS: The mean size of tumors was significantly bigger in the transanal local excision group (0.8 ± 0.2 versus 1.1 ± 0.5 cm; P = 0.018). En bloc resection was achieved for 30 patients (97 %) in the endoscopic submucosal dissection group and all the patients in the transanal local excision group. The operation time was longer in the transanal local excision than that in the endoscopic submucosal dissection group (40.0 ± 22.7 min versus 12.2 ± 5.3 min; P < 0.001). Complications in the transanal local excision group were five cases of acute retention of urine. There was no local recurrence or distant metastasis in either group during the follow-up period. CONCLUSION: For the treatment of rectal carcinoid tumors with diameter <1 cm, endoscopic submucosal dissection has better short-term clinical outcomes than transanal local excision in terms of faster recovery and possibly a lower morbidity rate. Transanal local excision may be the first therapeutic choice of scar-embedded rectal carcinoid tumors.

Lever reduction using polyaxial screw and rod fixation system for the treatment of degenerative lumbar spondylolisthesis with spinal stenosis: technique and clinical outcome.

BACKGROUND: The management for degenerative lumbar spondylolisthesis with spinal stenosis remains controversial. Reduction of lumbar spondylolisthesis has been performed via numerous techniques. Most of them need extra reduction assembly. METHODS: In this retrospective analysis, 27 patients of degenerative lumbar spondylolisthesis with spinal stenosis underwent reduction using polyaxial screw and rod constructs and posterolateral fusion. The average age at the time of surgery was 53 ± 3.23 years. The outcome measures consisted of a radiographic assessment of deformity and fusion rate and a clinical assessment of perioperative improvement in low back pain and function. Preoperative and postoperative radiographic evaluation included the percent slip, slip angle, and the lumbar lordosis between L1 and the sacrum measured using the Cobb method. Before surgery and at the final follow-up, the Oswestry Disability Index (ODI) and the visual pain analog scale (VPAS) between 0 (no pain) and 10 (maximal pain) were quantified. RESULTS: The average follow-up period more than 5 years was available. The mean operative time was 90.19 ± 14.51 min, and the mean blood loss during surgery was 152.59 ± 45.71 ml. The mean length of incision was 4.83 ± 0.63 cm. The average percent slippage and the mean slip angle were, respectively, 19.8 ± 4.49% and 9.69 ± 3.79° before surgery, 5.09 ± 3.40% and 6.39 ± 3.16° after surgery, and 5.67 ± 3.92% and 7.21 ± 3.05° at the last follow-up. The average lumbar lordosis was 36.88 ± 2.64° before surgery, 41.96 ± 1.64° after surgery, and 40.27 ± 1.19° at the final follow-up. No neurologic deficit occurred. Solid fusion was achieved for all cases. Compared with the outcome preoperation, the data improved from 6.56 ± 1.40 to 2.48 ± 1.16 for VPAS pain scores and from 32.22 ± 3.57 to 10.93 ± 4.93 for the ODI at the final follow-up. CONCLUSIONS: Lever slip reduction maneuver techniques using polyaxial screw and rod fixation system was simple and practicable. The treatment outcomes showed satisfactory radiographic characteristics and clinical results. The length of the incision was relatively small with a low intraoperative blood loss and short operation time.

[Molecular classification of colorectal carcinoma based on integration of gene expression profile and copy number variation].

OBJECTIVE: To classify colorectal carcinoma (CRC) by TNM staging integrated with the gene expression profile and copy number variation (CNV). METHODS: Profile data of gene expression and CNV of CRC were downloaded from public database and processed with batch bias adjustment, quartile normalization, missing value estimation and feature filtration. The processed profiles of mRNA and CNV were introduced into the codes of Bayesian consensus clustering (BCC) method and were used to calculate the subclasses of CRC. With the follow-up information of disease free survival of CRC patients, the prognostic values of the subclasses was investigated and the software of function enrichment analysis was employed to discover the major pathway signaling to each interesting subclass. All statistic analyses were performed under R-3.0.1 environment or by using SPSS 16.0 software. RESULTS: Profile data of gene expression and corresponding CNV from 335 CRC patients with TNM stage Ⅱ-Ⅲ and followed-up information were obtained. After feature filtering, the profiles contained 1578 probes of mRNA and 345 location of CNV. Four CRC subclasses were identified by the integrative analysis with BCC, and the concordances of BCC subclasses and each of gene-based subclasses (Cramer's V=0.49), CNV-based subclasses (Cramer's V=0.51) and Marisa's subclasses (Cramer's V=0.32) were statistically significant (Ps<0.001). Among BCC subclasses, BCC-I had a favorable prognosis, while BCC-Ⅳ had more unfavorable prognosis. The differences of prognosis were significant among BCC-I, BCC-(Ⅱ+Ⅲ) and BCC-Ⅳ with an overall log-rank P<0.001. The top enriched function was DNA damage and repair signaling when BCC-I compared to BCC-Ⅳ, and the new subgroups classified by the genes associated with enriched signaling had the better prognostic value than BCC subclasses but both of them were significantly correlated (Cramer's V=0.39, P<0.001). CONCLUSION: BCC method is effective to integrate multi-type genomic data for molecular classification of colorectal carcinoma, and the BCC-Ⅳ subclass has poor prognosis, which may be associated with the decreased repairing function of DNA damage.

[Emergence application of colonoscopic placement of self-expandable metal stent without fluoroscopic monitoring].

OBJECTIVE: To evaluate the efficacy and safety of colonoscopy-guided placement of self-expandable metallic stent without fluoroscopic monitoring in the emergence management for acute malignant colorectal obstruction. METHODS: Clinical data of 42 patients (24 males and 18 females with a mean age of 64.3 years) undergoing colonoscopy-guided placement of self-expandable metallic stents without fluoroscopic monitoring for acute malignant colorectal obstruction between January 2010 and June 2012 were reviewed retrospectively. RESULTS: The obstruction was located in the rectum (n=19), sigmoid (n=9), descending colon (n=8), splenic flexure (n=1), hepatic flexure (n=3), and ascending colon (n=2). Technical success was achieved in all the 42 patients (100%). The mean time of operation was (11.8±10.4) min (range 1.1-51.0 min). No serious procedure-related complication occurred. Minor bleeding occurred in 3 cases (7.1%). One patient died on the second day after surgery because of heart failure. CONCLUSIONS: Colonoscopy-guided placement of self-expandable metallic stents without fluoroscopic monitoring in emergence management for acute malignant colorectal obstruction is effective and safe with shorter operative time.

[Colonoscopic restoration for sigmoid vovulus in the elderly].

OBJECTIVE: To investigate the emergency therapeutic strategy for sigmoid vovulus in the elderly. METHODS: Clinical data of 14 elderly patients with sigmoid vovulus were analyzed retrospectively. RESULTS: The mean age was(79.1±7.2) years(range, 70-93), and 11 patients (78.6%) were male. Emergency decompression and restoration with colonoscopy was performed in all the patients with a success rate of 100%. No patient required emergent surgery. Four patients(28.6%) recurred and they were managed well by repeat colonoscopic restoration. CONCLUSION: Emergency colonoscopic restoration is the first treatment of choice for sigmoid vovulus in the elderly because it is safe and effective, and can be performed repeatedly.

[Surgical treatment of recurrent colorectal carcinoma in the elderly].

OBJECTIVE: To evaluate the safety and efficacy of surgical treatment for recurrent colorectal carcinoma in the elderly. METHODS: The clinical and follow up data of 24 elderly patients with recurrent colorectal carcinoma who were treated between January 2000 and June 2009 at the Changhai hospital of the Second Military Medical University were analyzed retrospectively. RESULTS: Among the 24 patients there were 14 men and 10 women. The mean age of the patients was 76.9 ± 5.3 years. The local recurrence was found in 15 patients. In 9 patients, both distant metastases and local recurrence were found. A total of 24 patients received operation, including radical resection in 15 patients and palliative resection in 8 patients. One patient had laparotomy only because of diffuse metastases in the abdomen and involvement of the duodenum and common bile duct.The patient received stent placement in the common bile duct and chemotherapy after the surgery. Postoperative complication occurred in 7(29.2%) patients, which included ileus(n=1), pulmonary infection(n=1), urinary infection(n=1), wound infection(n=2), wound dehiscence(n=1), and wound fat liquefaction(n=1). There were no perioperative deaths. The median survival time was 6 months in the entire cohort. The median survival time was 33 months in patients undergoing radical resection, and the 1-, 3-, and 5-year survival rate was 71.4%, 28.6%, and 14.3%. The median survival time was 3 months in patients who underwent palliative resection, and the 1-year survival rate was 0. The difference between the two groups was statistically significant(P<0.01). CONCLUSION: Outcomes are acceptable after radical resection for elderly patients with recurrent colorectal cancer if careful preoperative evaluation and perioperative management are performed.

Posterior unilateral pedicle subtraction osteotomy of hemivertebra for correction of the adolescent congenital spinal deformity.

BACKGROUND CONTEXT: The treatment of adolescent congenital deformity (late-diagnosed congenital deformity) is still unknown. The best candidates for hemivertebra excision are young patients, typically between 4 and 6 years of age. Partial excision may be feasible for older children. PURPOSE: The purpose of this study was to assess the effect of unilateral pedicle subtraction osteotomy of hemivertebra for correction of the adolescent congenital spinal deformity. STUDY DESIGN: Retrospective analysis. PATIENT SAMPLE: Twelve patients with adolescent congenital deformity who underwent posterior unilateral pedicle subtraction osteotomy and correction were evaluated. Mean age at the time of surgery was 17 years. OUTCOME MEASURES: The charts, standing full-length posteroanterior and lateral view radiographs, and functional measures were reviewed. METHODS: For evaluation of surgical effectiveness, comparative analysis of the parameters of the total main curve, the segmental curve, the compensatory cranial and caudal curves, the segmental kyphosis, and the trunk shift before and after operation and at the most recent follow-up was done. RESULTS: The mean follow-up period was 40.5 months. Mean Cobb angles of the total main curve and the segmental curve were, respectively, 47.5° and 43.8° before surgery, 23.7° and 16.5° after surgery, and 22.6° and 17° at the last follow-up. The angle of segmental kyphosis was 11.8° before surgery, 6.2° after surgery, and 7.8° (range, -30° to 26°) at the final follow-up. The mean final global lordosis was within the normal range. No neurologic deficit occurred. Solid fusion was achieved for all cases. CONCLUSIONS: Unilateral pedicle subtraction osteotomy with instrumentation from a posterior-only approach is indicated in older teenagers for an adolescent congenital spinal deformity. Compared with hemivertebra excision, corrective surgery with hemivertebra osteotomy has a lower intraoperative blood loss and shorter operation time.

[Analysis on misdiagnosis of 271 patients with rectal cancer].

OBJECTIVE: To investigate the common reasons for the misdiagnosis of rectal cancer. METHODS: A retrospective study was performed in 568 cases of rectal cancer in the Changhai Hospital from January 2007 to December 2008. Age at diagnosis, gender distribution, symptom, delay in diagnosis, TNM stage, and grade of differentiation were recorded and analyzed. The importance of digital examination and colonoscopy were addressed. RESULTS: Two hundred and seventy-one(47.7%) out of 568 patients were misdiagnosed for iatrogenic reasons. Rectal cancer patients who presented hematochezia were more likely to be misdiagnosed. There were 110 cases of stage III(40.6%) and 68 cases of stage IV(12.5%) in patients who were misdiagnosed, which was significantly higher than those who were diagnosed correctly(P<0.05). Patients under 40 years old were more likely to be misdiagnosed, and their correct diagnosis was often delayed longer and the tumors were in more advanced stage as compared to the older groups(P<0.05). CONCLUSIONS: The misdiagnosis rate of rectal cancer is high. Tumor stage of patients misdiagnosed is significantly more advanced than those who are correctly diagnosed. Digital examination and colonoscopy should be emphasized, especially for patients under the age of 40.

Rectal perforation after procedure for prolapse and hemorrhoids: possible causes.

PURPOSE: Our aim was to explore possible causes of rectal perforation occurring in patients who undergo the procedure for prolapse and hemorrhoids. METHODS: We evaluated data from cases of rectal perforation that occurred after the procedure for prolapse and hemorrhoids in China in conjunction with case reports from the international medical literature. RESULTS: We identified 7 patients from 5 hospitals in 2 provinces of China who had rectal perforation after the procedure despite having received prophylactic antibiotic treatment. Two patients had a disrupted staple line and 5 had perforations on the rectum wall above the intact staple line. Six patients presented with symptoms in the first 3 days after the procedure. Three patients had concomitant disease: 1 had concomitant constipation and internal rectal prolapse, 1 had concomitant constipation, and 1 had concomitant liver cirrhosis ascites that was not diagnosed preoperatively. Of the 15 cases of rectal perforation found in the literature, 3 patients had an intact staple line and 5 patients had a ruptured staple line. CONCLUSION: The cone-shaped tip of the anvil, concomitant rectal prolapse and pelvic floor descent, and concomitant ascites are possible causes of rectal perforation after the procedure for prolapse and hemorrhoids.

[Effect of colonoscopy combined with placement of metallic clips on selecting colonic surgery incision].

OBJECTIVE: To evaluate the accuracy and value of the placement of metallic clips during colonoscopy in the localization of colorectal cancer and incision selection. METHODS: A total of 30 patients received metallic clip placement by colonoscopy before operation. Abdominal plain film (supine and upright position) was taken and incision was determined by the projection of clips on the abdominal wall. RESULTS: The inaccuracy rate of localization by colonoscopy was 30%(9/30). Colonoscopy combined with the placement of metallic clips achieved an accurate incision rate of 100% (30/30). CONCLUSIONS: There is a considerable rate of inaccuracy for localization in colonic cancer by colonoscopy. Colonoscopy combined with placement of metallic clips should be considered in order to select a reasonable incision.

Diagnosis and treatment of diffuse cavernous hemangioma of the rectum: report of 17 cases.

BACKGROUND: Diffuse cavernous hemangioma of the rectum (DCHR) is a rare benign vascular disease, which is often misdiagnosed and difficult to treat. METHODS: Seventeen cases of DCHR in our hospitals from 1995 to 2009 were identified. The detailed data of diagnosis, treatment, and prognosis were carefully studied. RESULTS: Seven, three, two, and one patient were mistaken as having hemorrhoids, colitis, portal hypertension, and rectal polypus, respectively. The mean delay time between initial symptoms and final diagnosis was 17.63 years (range = 0-48 years). Colonoscopy and MRI were important in the diagnosis of DCHR because of their high positive rates and specific features. All of the lesions originated from the dentate line, extending to the proximal colorectal wall. Most of the lesions were found to be restricted to the rectosigmoid wall and the rectal mesentery. Involvement of right gluteus maximus and right leg was revealed by MRI in two patients. After admission, six patients underwent coloanal sleeve anastomosis and seven patients underwent pull-through transection and coloanal anastomosis. The latter procedure was superior to the former with respect to length of operation, intraoperative blood loss, intraoperative blood transfusion, and perioperative complications. CONCLUSION: DCHR is often misdiagnosed. Preoperative colonoscopy and MRI are essential in making the correct diagnosis and to depict the extent of the lesion accurately. Due to its origination from the dentate line and the involvement of the whole layer of the rectal wall and the rectal mesentery, the treatment of choice for DCHR is complete resection by the pull-through transection and coloanal anastomosis.

[Factors associated with anastomotic leakage after anterior resection in rectal cancer].

OBJECTIVE: To analyze the factors associated with anastomotic leakage after anterior resection in rectal cancer with the technique of total mesorectal excision (TME). METHODS: From January 2005 and December 2007, 738 consecutive patients with rectal cancer underwent anterior resection. The data of those patients was collected and reviewed retrospectively. The associations between anastomotic leakage and 9 patient-related variables as well as 7 surgical-related variables were examined. RESULTS: Low rectal cancer (located 7 cm or less above the anal edge), non-specialized surgeon and transanal tube use were the risk factors associated with anastomotic leakage on univariate analysis. The anastomotic leakage rate of low-rectal cancer was significantly higher than that of high-rectal cancer (5.9% vs. 0.9%, P = 0.003). The anastomotic leakage rate of the cases operated by colorectal surgeon was significantly lower than that of the cases operated by non-specialized surgeon (3.9% vs. 11.3%, P = 0.031). There was a tendency for colorectal surgeons to operate on a greater proportion of low rectal cancer than non-specialized surgeons (72.1% vs. 52.8%, P = 0.003). The leakage rate of transanal tube group was unexpectedly higher than that in patients without transanal tube (14.5% vs. 3.6%, P < 0.001). On multivariate logistic regression analysis, diabetes mellitus (P = 0.027), distance less than 1 cm from tumor to distal resection margin (P = 0.009) and defunctioning stoma (P = 0.031) were also associated with anastomotic leakage rate besides low rectal cancer, non-specialized surgeon and transanal tube use. In a further analysis of 522 patients with low rectal cancer, the leakage rate of defunctioning stoma group was significantly lower than that of non-stoma group (2.9% vs. 8.5%, P = 0.007). By contract, the leakage rate of transanal tube group was still higher than that in patients without transanal tube (15.1% vs. 4.9%, P = 0.008) because of its poor protective effect as well as the selection bias. CONCLUSIONS: Low-rectal cancer, non-specialized surgeons and diabetes mellitus are risk factors of anastomotic leakage after rectal surgery. A defunctioning stoma was effective in preventing leakage after low-rectal cancer surgery.

Influencing factors of symptomatic anastomotic leakage after anterior resection of the rectum for cancer.

BACKGROUND: The aim of the present study was to analyze the factors associated with anastomotic leakage after anterior resection for rectal cancer. METHODS: Retrospectively collected consecutive data of 738 rectal cancer patients who underwent anterior resection in our hospital between 2005 and 2008 were reviewed. The associations between 15 patient-related and surgery-related variables and anastomotic leakage were studied with both the univariate chi-square test and multivariate logistic regression analysis. RESULTS: Univariate analysis showed that risk factors associated with anastomotic leakage were low rectal cancer (located 5 cm or less above the dentate line) (5.9% vs. 0.9%; P = 0.003), non-specialized surgeon (3.9% vs. 11.3%; P = 0.031), and defunctioning transanal catheter placement (14.5% vs. 3.6%; P < 0.001). It should be noted that the mean surgeon case volumes of anterior resection of colorectal surgeons and non-specialized general surgeons were 43 per year and 2 per year, respectively (P < 0.001). In addition, there was a tendency for colorectal surgeons to operate on a greater proportion of low rectal cancers (72.1% vs. 52.8%; P = 0.003). In the multivariate analysis, besides low rectal cancer, non-specialized surgeon, and transanal catheter placement, three other factors were associated with anastomotic leakage: diabetes mellitus (P = 0.027), free distal margins less than 1 cm (P = 0.009), and a defunctioning stoma (P = 0.031). In a further analysis of 522 patients with low rectal cancer, the leakage rate in patients with a defunctioning stoma was significantly lower (2.9% vs. 8.5%; P = 0.007). By contrast, the leakage rate in the transanal catheter placement group was higher (15.1% vs. 4.9%; P = 0.008), because of its poor protective effect as well as the selection bias. CONCLUSIONS: From the findings of this study, we believe that low rectal cancer, non-specialized surgeons, and diabetes mellitus are risk factors for anastomotic leakage after rectal surgery, and that a defunctioning stoma could significantly reduce the incidence of leakage in low rectal cancer patients.

[Pull-through transection and anastomosis for early lower rectal cancer using double stapling technique].

OBJECTIVE: To introduce the experiences of pull-through transection and double stapling anastomosis for early lower rectal cancer. METHODS: From May 2001 to March 2008, 25 patients with early stage lower rectal cancer were operated by using pull-through transection and double stapling anastomosis. The average distance between the dentate line and lower margin of the tumor is (3.2 +/- 0.5) cm (2.0 - 4.5 cm). The average tumor diameter is (2.8 +/- 0.8) cm (2.0 - 3.5 cm). RESULTS: The average distance between the lower margin of the tumor and transection line is (1.5 +/- 0.4) cm (1.1 - 2.2 cm). All the resection margins were negative. Eighteen cases of the anastomosis were above the dentate line, 0.3 - 2.1 cm [(1.7 +/- 0.2) cm] and the other 7 were below, 0.1 - 0.5 cm (average 0.3 cm). Anastomotic leakage occurred in 1 case, and cured with conservative treatment. Local recurrence occurred in 1 case (4.0%), liver metastasis in 3 (12.0%) and lung metastasis in 2(8.0%), respectively. Mild fecal incontinence occurred in 7 cases. CONCLUSION: Compared with trans-abdominal transection of distal rectum in low anterior resection of rectal cancer, pull-through transection and anastomosis provides more precise control of the cutting line and simpler resection.