Impact of biliary drainage method before pancreaticoduodenectomy on short- and long-term outcomes in patients with periampullary carcinoma and obstructive jaundice: A multicenter retrospective analysis.

BACKGROUND: The optima preoperative biliary drainage before pancreaticoduodenectomy in patients with biliary tract and pancreatic cancer remains controversial. METHODS: A total of 898 patients who underwent preoperative biliary drainage via endoscopic retrograde biliary drainage, endoscopic transnasal biliary drainage, or percutaneous transhepatic biliary drainage before pancreaticoduodenectomy for biliary tract and pancreatic cancer were included. Perioperative and long-term outcomes were analyzed. RESULTS: The Clavien-Dindo grade ≥3 morbidity rates after pancreaticoduodenectomy were higher in the endoscopic retrograde biliary drainage (21.9%; P = .001) or endoscopic transnasal biliary drainage (20.2%; P = .007) than in the percutaneous transhepatic biliary drainage (9.7%) groups. In biliary tract cancer, the frequency of dissemination after pancreaticoduodenectomy was higher in the percutaneous transhepatic biliary drainage (15.3%) than in the endoscopic retrograde biliary drainage (0.7%; P = .001) and endoscopic transnasal biliary drainage (4.1%; P = .037) groups; percutaneous transhepatic biliary drainage was an independent factor associated with worse disease-free survival (P = .04), whereas in pancreatic cancer the frequency of dissemination and survival was comparable among the 3 preoperative biliary drainage methods. Albumin <3.9 g/dL was independently associated with worse overall survival in patients with both pancreatic (P = .038) and biliary tract (P = .002) cancers, respectively. During biliary drainage, external drainage (P = .038) was independently associated with albumin <3.9 g/dL; albumin was higher in endoscopic retrograde biliary drainage group than in endoscopic transnasal biliary drainage or percutaneous transhepatic biliary drainage groups after 21 days from tube insertion. CONCLUSION: In biliary tract cancer, percutaneous transhepatic biliary drainage may carry the risk of increasing the incidence of disseminative recurrence. In pancreatic cancer, percutaneous transhepatic biliary drainage is preferable owing to fewer complications without influencing recurrence. However, if patients cannot undergo surgery immediately, endoscopic retrograde biliary drainage will be applicable to help the preservation of nutritional status, which can have an impact on survival.

Relationship of oral bacterial number with medical hospitalization costs in analysis of Diagnosis Procedure Combination database from single institution in Japan.

Oral bacteria are known to be associated with perioperative complications during hospitalization. However, no presented reports have clarified the relationship of oral bacterial number with medical costs for inpatients. The Diagnosis Procedure Combination (DPC) database system used in Japan provides clinical information regarding acute hospital patients. The present study was conducted to determine the association of oral bacterial numbers in individual patients treated at a single institution with length of hospital stay and medical costs using DPC data. A total of 2369 patients referred by the medical department to the dental department at Hiroshima University Hospital were divided into the low (n = 2060) and high (n = 309) oral bacterial number groups. Length of hospital stay and medical costs were compared between the groups, as well as the associations of number of oral bacteria with Charlson comorbidity index (CCI)-related diseases in regard to mortality and disease severity. There was no significant difference in hospital stay length between the low (24.3 ± 24.2 days) and high (22.8 ± 20.1 days) oral bacterial number groups. On the other hand, the daily hospital medical cost in the high group was significantly greater (US$1456.2 ± 1505.7 vs. US$1185.7 ± 1128.6, P < 0.001). Additionally, there was no significant difference in CCI score between the groups, whereas the daily hospital medical costs for patients in the high group treated for cardiovascular disease or malignant tumors were greater than in the low number group (P < 0.05). Multivariate regression analysis was also performed, which showed that oral bacterial number, age, gender, BMI, cardiovascular disease, diabetes, malignant tumor, and hospital stay length were independently associated with daily hospitalization costs. Monitoring and oral care treatment to lower the number of oral bacteria in patients affected by cardiovascular disease or cancer may contribute to reduce hospitalization costs.

Survival outcome of patient with pT1N0 biliary tract cancer treated with surgery alone.

INTRODUCTION: Adjuvant chemotherapy (AC) with S-1 or capecitabine monotherapy is now the standard of care for resected biliary tract cancer (BTC) according to the Adjuvant S-1 for Cholangiocarcinoma Trial (ASCOT) and the BILCAP study. Patients selection criteria, especially regarding pT1N0 BTC, differed in both trials. We aimed to clarify the survival outcomes regarding resected pT1N0 BTC without AC. METHODS: Among patients with macroscopically complete resection for BTC treated without AC between September 1992 and December 2020, the survival outcomes of those with pT1N0 BTC, except for intrahepatic cholangiocarcinoma, according to the Union for International Cancer Control 7th and 8th edition (TNM7 and 8), were investigated. RESULTS: Of 749 patients who underwent curative resection for BTC, 69 were identified as having pT1N0 BTC according to TNM8. Six patients (9 %) developed recurrence during the median follow-up period of 53 months (range: 14-263 months) with only one patient (2 %) being pT1N0 according to TNM7. Based on TNM8, the 5-year recurrence-free survival, disease-specific survival, and overall survival reached 90.7 % (95 % confidence interval [CI]: 80.3-95.7 %), 96.4 % (95 % CI: 86.1-99.1 %), and 85.3 % (95 % CI: 71.2-92.8 %), respectively. Perineural invasion (PNI) was significantly associated with recurrence, and the recurrence rate in patients with PNI reached as high as 40 %. CONCLUSIONS: The survival outcomes regarding resected pT1N0 BTC according to TNM7 were excellent without AC; however, those of TNM8 were not, with PNI being associated with recurrence risk.

Videofluoroscopic analysis of the laryngeal movement of older adults in swallowing.

Even without diseases that cause dysphagia, physiological swallowing function declines with age, increasing the risk of aspiration. This study analyzed age-related changes in laryngeal movement in older adults. The study population consisted of 10 volunteers in their 80s and six in their 20s. A videofluoroscopic study of 3 and 10 mL barium swallows was performed laterally using a digital fluorographic. The recorded images were retrieved to a personal computer and analyzed frame-by-frame using video analysis software. The movement of the larynx during swallowing, barium's pharyngeal transit time (PTT), and laryngeal elevation delay time (LEDT) were analyzed. Results were compared between the 20s and 80s age groups using statistical analyses. The PTT was shorter in the 20s than in the 80s age group. The PTT was significantly longer in the 80s group than in the 20s for both 3 and 10 mL barium swallows. LEDT in the 80s was statistically significantly longer than that in the 20s for the 10 ml barium. No statistically significant differences were found; however, there was a tendency for the 80s group to have more types of laryngeal movement velocity peaks. In this study, LEDT was prolonged in the 80s with 10 ml barium swallowing than in the 20s. Two peak patterns of laryngeal elevation during swallowing were observed. The velocity peaks showed a two-peak pattern when the patients were in their 80s and when the barium volume was tested at 10 mL. Our results suggest that aging's effect on swallowing relates to laryngeal elevation.

Can oral diadochokinesis be used as an assessment tool of oral function in older adults requiring care in nursing home?

BACKGROUND: Oral diadochokinesis (OD) test is an articulation test that analyses fine movements of the lips, cheeks and tongue. It is difficult to perform the test accurately in older people with reduced physical and cognitive functions. OBJECTIVES: This study aimed to investigate the number of older adults who could not be tested for OD and to investigate their characteristics. METHODS: The participants included 145 older residents of an aged care nursing home. They were divided into two groups: those who could be tested for OD and those who could not, and their characteristics were compared. The degree of requiring long-term care was classified into five levels. The degree of dementia was classified into five levels. Those having difficulty in performing daily activities alone and having degree III or higher dementia were considered to have severe dementia. RESULTS: The participants included 41 men and 104 women with a median age of 89 years (range, 64-105 years). Sixty-eight participants failed the OD test (46.9%). In univariate and multivariate analyses, degree of dementia and oral care (among other characteristics in univariate analysis) showed statistically significant differences between the two groups. Cut-off values for older adults who could not perform OD test were level 4 or higher in need of care and degree III or higher in dementia. CONCLUSION: This study suggests that additional assessment tools for oral function should be considered for older adults requiring a nursing care level of 4 or higher and a dementia degree of III or higher.

Retrospective analysis of tooth extraction and osteoradionecrosis after low-dose rate brachytherapy for patients with tongue cancer.

OBJECTIVES: This study aimed to investigate the incidence of osteonecrosis of the jawbones (ORN) after tooth extraction in patients undergoing low-dose rate brachytherapy (LDR-BT) and assess its safety. METHODS: This study retrospectively analyzed 145 patients with tongue cancer treated at Hiroshima University Hospital from 2007 to 2021 with LDR-BT using 192Ir or 198Au alone, LDR-BT and external beam radiotherapy (EBRT) with or without chemotherapy, and LDR-BT with chemotherapy. Patients' mandible and maxilla were protected with spacers. Forty-seven patients underwent tooth extraction, and the incidence, site, and relationship of ORN with tooth extraction were recorded. A subgroup of 26 patients received additional EBRT to the neck after dissection for late cervical lymph node metastases. RESULTS: Of 145 patients, six (4.1%) developed ORN on the same side of the mandible as LDR-BT, and EBRT was performed before and/or after LDR-BT on the sites where ORNs developed. Five of 47 (10.6%) patients who underwent tooth extraction after LDR-BT developed ORN. ORN incidence was 1.8% (2/109) in the LDR-BT and/or chemotherapy group and 11.1% (4/36) in the combination LDR-BT and EBRT and/or chemotherapy group for primary tongue cancer. Different irradiation methods (LDR-BT and/or chemotherapy and combination LDR-BT and EBRT and/or chemotherapy) and the presence or absence of tooth extraction showed significant differences (p = 0.0335 and p = 0.0139, respectively) with or without ORN. CONCLUSIONS: Mandibular tooth extraction should be avoided on the side of LDR-BT in combined EBRT cases. However, tooth extraction is feasible using a spacer in LDR-BT and/or chemotherapy.

Cone-beam computed tomography-based investigation of pre-eruptive intracoronal resorption prevalence.

This retrospective study aimed to investigate the prevalence of pre-eruptive intracoronal resorption (PEIR) using cone-beam computed tomography (CBCT) and to explore the mechanism and characteristics of PEIR development. CBCT images of patients aged ≤ 20 years with unerupted teeth at Hiroshima University Hospital were collected. We examined 1530 patients with 10,576 unerupted teeth. Teeth with PEIR were identified for the detailed location and size of the PEIR in the crown using multiplanar reconstruction. The subject and tooth prevalence rates of PEIR were 1.96% and 0.31%, respectively. The teeth that were the most commonly affected by PEIR were mandibular third molars (3.09%). The prevalence of PEIR was significantly higher in females than in males, and higher in the mandible than in the maxilla. No significant difference between in the position of PEIR within the crown was observed. Moreover, CBCT imaging revealed the onset of PEIR in one case. This study demonstrated the prevalence of PEIR and identified statistically significant sex- and location-based differences. Furthermore, one case of CBCT imaging supports the hypothesis that the onset of PEIR was due to resorption after completion of the crown.

Radiation doses of medical radiation workers performing low-dose-rate brachytherapy with 198Au grains and 192Ir pins for patients with oral cancers.

OBJECTIVES: Low-dose-rate brachytherapy (LDR-BT) with 198Au grains and 192Ir pins is an essential treatment option for oral cancer due to its high rate of local control and low invasiveness. However, the radiation exposure of medical radiation workers is concerning. Thus, we aimed to determine the radiation dose delivered to medical radiation workers during LDR-BT using 198Au grains and 192Ir pins for oral cancer. METHODS: Thirty-two patients with oral cancer underwent 198Au grain interstitial LDR-BT between June 2016 and May 2023, and 23 patients with tongue cancer underwent 192Ir pin interstitial LDR-BT between March 2015 and November 2017 at our hospital. Dosimetry was performed by attaching a dosimeter to the chest pocket of the operator and assistant during 198Au grain or 192Ir pin LDR-BT. Since the operator also loads 198Au grains into the implantation device, the operator's radiation dose includes the dose received during this preparation. RESULTS: Mean radiation doses of the operators with 198Au grain and 192Ir pin LDR-BT were 165.8 and 211.2 µSv, respectively. Statistically significant differences between the radioactive sources of 198Au grain and 192Ir pin LDR-BT were observed (p = 0.0459). The mean radiation doses of the assistants with 198Au grain and 192Ir pin LDR-BT were 92.0 and 162.0 µSv, respectively. Statistically significant differences were observed between the radioactive sources of 198Au grains and 192Ir pin LDR-BT (p = 0.0003). CONCLUSIONS: Regarding radioactive source differences, 192Ir pin LDR-BT resulted in higher doses delivered to medical radiation workers than 198Au grain LDR-BT.

Feasibility of S-1 adjuvant chemotherapy after major hepatectomy for biliary tract cancers: An exploratory subset analysis of JCOG1202.

INTRODUCTION: Major hepatectomy (MH) may produce the impaired liver function and affect the feasibility of adjuvant chemotherapy in terms of early period after the surgery, but there have not been detailed investigations. JCOG1202 (UMIN000011688) is a randomized phase III trial demonstrating the superiority of adjuvant S-1 chemotherapy for biliary tract cancer (BTC). The aim of this study is to examine the influence of MH for BTC on adjuvant S-1. MATERIALS AND METHODS: Of the total 424 patients, 207 received S-1 (S-1 arm) while the remaining 217 were not. We compared MH with non-major hepatectomy (NMH) for BTC. RESULTS: In the S-1 arm, 42 had undergone MH, and 165 had undergone NMH. MH had similar pretreatment features to NMH, including the proportion of biliary reconstruction, to NMH, except for a lower platelet count (17.7 vs. 23.4 × 104/mm3, p < 0.0001) and lower serum albumin level (3.5 vs. 3.8 g/dL, p < 0.0001). The treatment completion proportion tended to be lower for MH than for NMH (59.5 % vs. 75.8 %; risk ratio, 0.786 [95 % confidence interval, 0.603-1.023], p = 0.0733), and the median dose intensity was lower as well (88.7 % vs. 99.6 %, p = 0.0358). The major reasons for discontinuation were biliary tract infections and gastrointestinal disorders after MH. The frequency of grade 3-4 biliary tract infection was 19.0 % in MH vs. 4.2 % in NMH. CONCLUSION: The treatment completion proportion and dose intensity were lower in MH than in NMH. Caution should be exercised against biliary tract infections and gastrointestinal disorders during adjuvant S-1 after MH for BTC.

Efficacy of Low-Level Laser Therapy for Oral Mucositis in Hematologic Patients Undergoing Transplantation: A Single-Arm Prospective Study.

Oral mucositis significantly affects the quality of life in hematologic cancer patients undergoing hematopoietic stem cell transplantation. Despite global evidence supporting the efficacy of low-level laser therapy (LLLT) for mucositis prevention, its clinical adoption in Japan is limited. This study aimed to fill this gap by evaluating the safety and efficacy of LLLT in a Japanese patient population. In a single-group, non-blinded, exploratory trial, we compared 21 LLLT-treated patients against a historical control of 96 patients. The primary endpoint was the incidence of Grade ≥ 2 mucositis, based on NCI-CTCAE ver. 4.0. The LLLT group showed a significantly lower incidence of Grade ≥ 2 mucositis (23.8%) compared to the control group (64.6%) (p = 0.0006). Furthermore, Grade ≥ 2 mucositis correlated with increased oral dryness and longer hospital stays. Our study confirms the efficacy of LLLT in reducing the onset of severe oral mucositis among Japanese hematologic cancer patients, advocating for its clinical introduction as a preventive measure in Japan.

Head and neck cancer patients show poor oral health as compared to those with other types of cancer.

PURPOSE: Several studies have found associations between periodontitis and various types of cancer. Since the site of head and neck cancer (HNC) has contiguity or proximity to the oral cavity, it may be particularly influenced by oral inflammation. This study aimed to determine whether HNC patients have poor oral health as compared to those with other types of cancer. METHODS: This study retrospectively examined oral environmental factors including periodontal inflamed surface area (PISA), a new periodontal inflammatory parameter. A total of 1030 cancer patients were divided into the HNC (n = 142) and other cancer (n = 888) groups. Furthermore, the HNC group was divided into high (n = 71) and low (n = 71) PISA subgroups, and independent risk factors affecting a high PISA value were investigated. RESULTS: Multivariate logistic regression analysis showed that number of missing teeth (odds ratio 1.72, 95% CI 1.15-2.56, P < 0.01), PISA (odds ratio 1.06, 95% CI 1.03-1.06, P < 0.05), and oral bacterial count (odds ratio 1.02, 95% CI 1.01-1.03, P < 0.01) were independent factors related to HNC. In addition, multivariate logistic regression analysis indicated that current smoker (odds ratio 7.51, 95% CI 1.63-34.71, P < 0.01) and presence of untreated dental caries (odds ratio 3.33, 95% CI 1.23-9.00, P < 0.05) were independent risk factors affecting high PISA values in HNC patients. CONCLUSION: HNC patients have higher levels of gingival inflammation and poor oral health as compared to patients with other types of cancer, indicating that prompt oral assessment and an effective oral hygiene management plan are needed at the time of HNC diagnosis.

Ultrasonographic features of mass lesions in the oral submucosal epithelium using intraoral ultrasonography.

BACKGROUND: Mass lesions occurring under the oral mucosal epithelium are often small and difficult to diagnose; however, intraoral ultrasonography can delineate these lesions. We aimed to investigate the features of submucosal mass lesions in the oral cavity using intraoral ultrasonography. METHODS: Fifty patients with hemangioma, irritation fibroma, mucous cyst, lipoma, and pleomorphic adenoma were included. Age, site, largest diameter, thickness, marginal morphology type, border type, internal echo posterior echo, and internal or peripheral Doppler images of the lesions were recorded. RESULTS: The hemangiomas were internally hypoechoic and exhibited a cord-like structure; irritation fibromas, mainly internally isoechoic; mucous cysts, hypoechoic; and the lipomas appeared as homogeneous, isoechoic, or hyperechoic images with unclear borders. Pleomorphic adenomas were surrounded by a single hypoechoic zone, suggesting a thick capsular structure, were predominantly isoechoic internally, and appeared as cyst-like hypoechoic images. CONCLUSIONS: The features of the lesions were identified and delineated using intraoral ultrasonography.

Radiomics analysis of intraoral ultrasound images for prediction of late cervical lymph node metastasis in patients with tongue cancer.

BACKGROUND: We investigated the predictability of late cervical lymph node metastasis using radiomics analysis of ultrasonographic images of tongue cancer. METHODS: We selected 120 patients with tongue cancer who underwent intraoral ultrasonography, 30 of which had late cervical lymph node metastasis. Radiomics analysis was used to extract and quantify the image features. Bootstrap forest (BF), support vector machine (SVM), and neural tanh boost (NTB) were used as the machine learning models, and receiver operating characteristic curve analysis was conducted to determine diagnostic performance. RESULTS: The sensitivity, specificity, accuracy, and AUC in the validation group were, respectively, 0.600, 0.967, 0.875, and 0.923 for the BF model; 0.700, 0.967, 0.900, and 0.950 for the SVM model; and 0.900, 0.967, 0.950, and 0.967 for NTB model. CONCLUSIONS: Radiomics analysis and machine learning models using ultrasonographic images of pretreated tongue cancer could predict late cervical lymph node metastasis with high accuracy.

A Multicenter Survey on Eligibility for a Randomized Phase III Trial of Adjuvant Chemotherapy for Resected Biliary Tract Cancer (JCOG1202, ASCOT).

BACKGROUND: The Adjuvant S-1 for Cholangiocarcinoma Trial (JCOG1202, [ASCOT]) was a multicenter, randomized controlled trial aimed at investigating the efficacy and safety of adjuvant chemotherapy (AC) with S-1 for resected biliary tract cancer (BTC). This trial reported that overall survival was prolonged with AC compared with observation. METHODS: With the aim of increasing enrollment, the present survey biannually recorded the number of patients eligible for enrollment into ASCOT and reasons for ineligibility among patients who had undergone surgery for BTC from April 2015 to September 2017 at 36 institutions participating in ASCOT. RESULTS: Of 2039 patients who underwent surgery for BTC, 211 (10.3%) were already enrolled, 166 (8.1%) were eligible but had not been enrolled, and 1662 (81.5%) were ineligible. Among ineligible patients, the predominant reasons for ineligibility were patient refusal (n = 332, 20.0%), pathologic stage (pT1N0; n = 248, 14.9%), age (≥ 81 years; n = 196, 11.8%), and prolonged postoperative complications (n = 176, 10.6%). CONCLUSIONS: Patients undergoing surgery for BTC are a heterogeneous cohort comprising patients with earlier pathologic stage, advanced age, and prolonged postoperative complications. These factors should be considered during the design of future clinical trials of perioperative treatments for resectable BTC.

Ghost cell odontogenic carcinoma arising in dentinogenic ghost cell tumor, peripheral: A case report.

Ghost cell odontogenic carcinoma (GCOC) is an extremely rare intraosseous malignant odontogenic tumor with prominent ghost cell keratinization and dentinoid formation. Here, we present the first case of GCOC arising in dentinogenic ghost cell tumor (DGCT), peripheral. The patient was a man in his 60s with an exophytic mass in the anterior part of lower gingiva. The resected tumor measured 4.5 cm in maximum diameter. Histologically, the nonencapsulated tumor proliferated in the gingiva without bone invasion. It was predominantly composed of ameloblastoma-like nests and islands of basaloid cells with ghost cells and dentinoid in the mature connective tissue, suggesting DGCT, peripheral. As minor components, sheets of atypical basaloid cells and ameloblastic carcinoma-like nests with pleomorphism and high proliferative activity (Ki-67 labeling index up to 40%) consistent with malignancy were identified. CTNNB1 mutation and ß-catenin nuclear translocation were observed in both benign and malignant components. Final diagnosis was GCOC arising in DGCT, peripheral. GCOC shows similar histological features to DGCT. In this unique case without invasion, the cytological atypia and high proliferative activity supports the diagnosis of malignant transformation from DGCT.

Liver functional assessment using time-associated change in the liver-to-spleen signal intensity ratio on enhanced magnetic resonance imaging: a retrospective study.

BACKGROUND: Liver-to-spleen signal intensity ratio (LSR) is evaluated by magnetic resonance imaging (MRI) in the hepatobiliary phase and has been reported as a useful radiological assessment of regional liver function. However, LSR is a passive (non-time-associated) assessment of liver function, not a dynamic (time-associated) assessment. Moreover, LSR shows limitations such as a dose bias of contrast medium and a timing bias of imaging. Previous studies have reported the advantages of time-associated liver functional assessment as a precise assessment of liver function. For instance, the indocyanine green (ICG) disappearance rate, which is calculated from serum ICG concentrations at multiple time points, reflects a precise preoperative liver function for predicting post-hepatectomy liver failure without the dose bias of ICG or the timing bias of blood sampling. The aim of this study was to develop a novel time-associated radiological liver functional assessment and verify its correlation with traditional liver functional parameters. METHODS: A total of 279 pancreatic cancer patients were evaluated to clarify fundamental time-associated changes to LSR in normal liver. We defined the time-associated radiological assessment of liver function, calculated using information on LSR from four time points, as the "LSR increasing rate" (LSRi). We then investigated correlations between LSRi and previous liver functional parameters. Furthermore, we evaluated how timing bias and protocol bias affect LSRi. RESULTS: Significant correlations were observed between LSRi and previous liver functional parameters such as total bilirubin, Child-Pugh grade, and albumin-bilirubin grade (P < 0.001 each). Moreover, considerably high correlations were observed between LSRi calculated using four time points and that calculated using three time points (r > 0.973 each), indicating that the timing bias of imaging was minimal. CONCLUSIONS: This study propose a novel time-associated radiological assessment, and revealed that the LSRi correlated significantly with traditional liver functional parameters. Changes in LSR over time may provide a superior preoperative assessment of regional liver function that is better for predicting post-hepatectomy liver failure than LSR using the hepatobiliary phase alone.

Relationships between physical and immunological tumor microenvironment in pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is physically palpated as a hard tumor with an unfavorable prognosis. Assessing physical features and their association with pathological features could help to elucidate the mechanism of physical abnormalities in cancer tissues. A total of 93 patients who underwent radical surgery for pancreatic and bile duct cancers at a single center hospital during a 28-month period were recruited for this study that aimed to estimate the stiffness of PDAC tissues compared to the other neoplasms and assess relationships between tumor stiffness and pathological features. Physical alterations and pathological features of PDAC, with or without preoperative therapy, were analyzed. The immunological tumor microenvironment was evaluated using multiplexed fluorescent immunohistochemistry. The stiffness of PDAC correlated with the ratio of Azan-Mallory staining, α-smooth muscle actin, and collagen I-positive areas of the tumors. Densities of CD8+ T cells and CD204+ macrophages were associated with tumor stiffness in cases without preoperative therapy. Pancreatic ductal adenocarcinoma treated with preoperative therapy was softer than that without, and the association between tumor stiffness and immune cell infiltration was not shown after preoperative therapy. We observed the relationship between tumor stiffness and immunological features in human PDAC for the first time. Immune cell densities in the tumor center were smaller in hard tumors than in soft tumors without preoperative therapies. Preoperative therapy could alter physical and immunological aspects, warranting further study. Understanding of the correlations between physical and immunological aspects could lead to the development of new therapies.

Effectiveness of Spacers in Brachytherapy With 198Au Grains for Patients With Buccal Mucosa Cancer.

BACKGROUND/AIM: The aim of this study was to investigate the use of spacers and their efficacy in brachytherapy with 198Au grains for buccal mucosa cancer. PATIENTS AND METHODS: Sixteen patients with squamous cell carcinoma of the buccal mucosa who were treated with 198Au grain brachytherapy were included. The distance between 198Au grains, distance between 198Au grains and the maxilla or mandible, and the maximum dose/cc to the jawbone (D1cc) with and without a spacer was investigated in three out of 16 patients. RESULTS: The median distance between 198Au grains without and with a spacer was 7.4 and 10.7 mm, respectively; this was significantly different. The median distance between 198Au grains and the maxilla without and with a spacer was 10.3 and 18.5 mm, respectively; again this was significantly different. The median distance between 198Au grains and the mandible without and with a spacer was 8.6 and 17.3 mm, respectively; the difference was significant. The D1cc to the maxilla without and with a spacer were 14.9, 68.7, and 51.8 Gy and 7.5, 21.2, and 40.7 Gy in cases 1, 2, and 3, respectively. The D1cc to the mandible without and with a spacer were 27.5, 68.7, and 85.8 Gy and 11.3, 53.6, and 64.9 Gy in cases 1, 2, and 3, respectively. No osteoradionecrosis of the jaw bones was observed in any case. CONCLUSION: The spacer enabled maintenance of the distance between 198Au grains, and between 198Au grains and the jawbone. In buccal mucosa cancer, using a spacer in brachytherapy with 198Au grains appears to reduce jawbone complications.