Evaluation of the prognostic impact of pathologic tumor regression grade on patients with colorectal cancer after preoperative chemoradiotherapy.

BACKGROUND: The prognostic value of the pathological response to preoperative chemoradiotherapy (CRT) in rectal cancer (RC) remains unknown. OBJECTIVES: We aimed to assess the predictive value of the response to CRT that was derived from an evaluation of the histological findings (whole-section vs. representative-section sampling) and attempted to determine an objective cut-off value for the tumor regression grade (TRG). METHODS: We examined the association of the TRG with the outcomes (recurrence-free survival [RFS] and overall survival [OS]) of 78 patients with RC. Patients with RC treated with preoperative CRT were divided into development (30 cases) and validation (48 cases) cohorts. The TRG was classified as grades I (Ia, Ib), II, and III. The cut-off value was determined by receiver operating characteristic (ROC) curve analysis. RESULTS: The TRG determined from whole-section sampling versus representative-section sampling was more strongly correlated with patient survival. We found that in both cohorts, patients with a cut-off value of <73% had a poor prognosis. Finally, the cut-off value was found to be an independent predictive factor in both univariate and multivariate analysis. CONCLUSIONS: The TRG that was used to evaluate patients with RC who underwent preoperative CRT was an independent prognostic factor for outcome.

Strangulated Bowel Obstruction Due to Hiatal Hernia After Laparoscopic Total Gastrectomy.

Laparoscopic total gastrectomy results in more internal hernias than open surgery. However, there are few reports of incarcerated hiatal hernia after laparoscopic total gastrectomy. Here, we report a case of a 79-year-old male who underwent urgent surgical intervention for a strangulated intestinal obstruction due to an incarcerated hernia through the esophageal hiatus following laparoscopic total gastrectomy. In this case, an esophageal hiatal hernia was present before gastrectomy, but was not repaired. Additionally, the patient experienced significant weight loss after gastrectomy. Preoperative hiatal hernia and marked postoperative weight loss may pose risks.

Prognostic impact and survival outcomes of colon perforation in patients with metastatic colorectal cancer: a multicenter retrospective cohort study.

BACKGROUND: Colon perforation caused by colorectal cancer (CRC) is a fatal condition requiring emergency intervention. For patients with metastatic lesions, surgeons face difficult decisions regarding whether to resect the primary and metastatic lesions. Moreover, there is currently no established treatment strategy for these patients. This study aimed to investigate the clinical practice and long-term outcomes of patients with metastatic CRC diagnosed with the onset of colon perforation. METHODS: We performed a population-based multicenter cohort study. Consecutive patients diagnosed with stage IV CRC between 2008 and 2015 at all designated cancer hospitals in Fukushima Prefecture, Japan, were enrolled in this study. We evaluated the impact of colon perforation on the survival outcomes of patients with metastatic CRC. The main outcome was the adjusted hazard ratio (aHR) of perforation for overall survival (OS). Survival time and HRs were estimated using Kaplan‒Meier and Cox proportional regression analyses. RESULTS: A total of 1258 patients were enrolled (perforation: n = 46; non-perforation: n = 1212). All but one of the patients with perforation underwent primary resection or colostomy and 25 cases were able to receive chemotherapy. The median OS for the perforation and non-perforation groups was 19.0 and 20.0 months, respectively (p = 0.96). Moreover, perforation was not an independent prognostic factor (aHR: 0.99; 95% confidence interval: 0.61-1.28). CONCLUSIONS: In metastatic CRC, perforation is not necessarily a poor prognostic factor. Patients with perforation who undergo primary tumor resection or colostomy and prompt initiation of systemic chemotherapy might be expected to have a survival time similar to that of patients with non-perforated colon.

Clinical Indicators to Determine the Timing of Surgery for Adhesive Small Bowel Obstruction.

BACKGROUND: Decompression of the intestine with a long tube or nasogastric tube is the first-choice treatment for adhesive small bowel obstruction (ASBO). Scheduling surgery while weighing the risks of surgery against conservative care is a crucial factor in clinical decision-making. Whenever feasible, unnecessary surgeries should be avoided, and it is essential to provide clinical markers for this. This study aimed to obtain evidence regarding the optimal timing of ASBO and when conservative treatment options are not successful. METHODS: The data of patients diagnosed with ASBO and receiving long tube insertion for more than 7 days were reviewed. We investigated transit ileal drainage volume and recurrence. The primary outcomes were the change in the drainage volume from the long tube over time and the percentage of patients who required surgery. We evaluated some cutoff values to determine the indication for surgery based on the insertion duration and volume of long tube drainage. RESULTS: Ninety-nine patients were enrolled in this study. Fifty-one patients showed improvement with conservative treatment, whereas 48 ultimately required surgery. When a daily drainage volume of ≥500 mL was considered an indication for surgery, 13-37 cases (25%-72%) would be judged unnecessary within 6 days of long tube insertion, while 5 cases (9.8%) would be judged unnecessary on day 7. DISCUSSION: Unnecessary surgical interventions for ASBO might be avoided by assessing the drainage volume on day 7 after inserting a long tube.

Blood Perfusion Assessment by Indocyanine Green Fluorescence Imaging for Minimally Invasive Rectal Cancer Surgery (EssentiAL trial): A Randomized Clinical Trial.

OBJECTIVE: The aim of the present randomized controlled trial was to evaluate the superiority of indocyanine green fluorescence imaging (ICG-FI) in reducing the rate of anastomotic leakage in minimally invasive rectal cancer surgery. BACKGROUND: The role of ICG-FI in anastomotic leakage in minimally invasive rectal cancer surgery is controversial according to the published literature. METHODS: This randomized, open-label, phase 3, trial was performed at 41 hospitals in Japan. Patients with clinically stage 0-III rectal carcinoma less than 12 cm from the anal verge, scheduled for minimally invasive sphincter-preserving surgery were preoperatively randomly assigned to receive a blood flow evaluation by ICG-FI (ICG+ group) or no blood flow evaluation by ICG-FI (ICG- group). The primary endpoint was the anastomotic leakage rate (grade A+B+C, expected reduction rate of 6%) analyzed in the modified intention-to-treat population. RESULTS: Between December 2018 and February 2021, a total of 850 patients were enrolled and randomized. After the exclusion of 11 patients, 839 were subject to the modified intention-to-treat population (422 in the ICG+ group and 417 in the ICG- group). The rate of anastomotic leakage (grade A+B+C) was significantly lower in the ICG+ group (7.6%) than in the ICG- group (11.8%) (relative risk, 0.645; 95% confidence interval 0.422-0.987; P =0.041). The rate of anastomotic leakage (grade B+C) was 4.7% in the ICG+ group and 8.2% in the ICG- group ( P =0.044), and the respective reoperation rates were 0.5% and 2.4% ( P =0.021). CONCLUSIONS: Although the actual reduction rate of anastomotic leakage in the ICG+ group was lower than the expected reduction rate and ICG-FI was not superior to white light, ICG-FI significantly reduced the anastomotic leakage rate by 4.2%.

Prognostic Role of Carcinoembryonic Antigen and Carbohydrate Antigen 19-9 in Stage IV Colorectal Cancer.

BACKGROUND/AIM: We investigated the association of the levels of serum carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9) with prognosis in patients with stage IV colorectal cancer at diagnosis. PATIENTS AND METHODS: In this multicenter retrospective cohort study, patients with serum CEA and CA19-9 measured at diagnosis of stage IV colorectal cancer were included. The cutoff values were 5 ng/ml for CEA and 37 U/ml for CA19-9. Patients were categorized into four groups: those with normal levels for both CEA and CA19-9; those with only an elevated CEA level; those with only an elevated CA19-9 level; and those with elevated levels of both. RESULTS: A total of 825 patients were included. Among them, 132 (16.0%) had normal levels for both markers, 258 (31.3%) had an elevated CEA level only, 33 (4.0%) had an elevated CA19-9 level only, and 402 (48.7%) had elevated levels of both CEA and CA19-9. Compared with patients with normal levels for both CEA and CA19-9, the multivariate hazard ratio for overall survival was 1.24 (95% confidence interval=0.95-1.62, p=0.12) for those with elevated CEA only, 2.04 (95% confidence interval=1.31-3.17, p=0.002) for those with elevated CA19-9 only, and 1.82 (95% confidence interval=1.41-2.32, p<0.001) in those with elevation of both CEA and CA19-9. CONCLUSION: Elevation of CEA alone was not prognostic. Elevation of only CA19-9 at diagnosis was associated with a worse prognosis in patients with stage IV colorectal cancer. The combined measurement of CEA and CA19-9 can be helpful as a predictive tool for the prognosis of stage IV colorectal cancer.

Impact of histological subtype on prognosis in stage IV colorectal cancer: A population-based cohort study.

BACKGROUND: There are a few established prognostic factors for stage IV colorectal cancer. Thus, this study aimed to evaluate the impact of histological subtypes on prognosis and metastatic patterns in patients with stage IV colorectal cancer. METHODS: This was a population-based, multicenter, cohort study. We included consecutive patients diagnosed with stage IV colorectal cancer between 2008 and 2015 at all designated cancer hospitals in Fukushima prefecture, Japan. Patients were classified into two groups according to histological subtypes as follows: poorly differentiated adenocarcinoma (Por), mucinous adenocarcinoma (Muc), or signet-ring cell carcinoma (Sig) and well (Wel) or moderately differentiated adenocarcinoma (Mod). We evaluated the relationship between these histological groups and survival time. After adjusting for other clinical factors, we calculated the hazard ratio for Por/Muc/Sig. RESULTS: A total of 1,151 patients were enrolled, and 1,031 and 120 had Wel/Mod and Por/Muc/Sig, respectively. The median overall survival was 19.2 and 11.9 months for Wel/Mod and Por/Muc/Sig, respectively (p < 0.001). The adjusted hazard ratio for Por/Muc/Sig with regard to survival time was 1.42 (95% confidence interval: 1.13-1.77). Por/Muc/Sig had a lower incidence of liver and lung metastases and a higher incidence of peritoneal dissemination and metastasis to rare organs, such as the bone and brain. CONCLUSIONS: The Por/Muc/Sig histological subtype was an independent prognostic factor for poor prognosis among patients with stage IV colorectal cancer. The histological subtype may be useful for predicting the prognosis of patients with stage IV colorectal cancer and designing the treatment strategy.

The additional diagnostic impact of positron emission tomography-computed tomography for lymph node metastasis from colorectal cancer: A prospective lymph node level analysis.

BACKGROUND: We conducted a prospective study to determine the diagnostic performance of positron emission tomography-computed tomography (PET-CT) for lymph node metastasis in colorectal cancer patients. METHODS: We enrolled patients scheduled to receive curative surgery with lymph node dissection for colorectal adenocarcinoma who underwent contrast-enhanced abdominopelvic CT and PET-CT before surgery and who had primary lesions of cT2 or deeper. A radiologist determined the fluorodeoxyglucose uptake and the standardized uptake value (SUV) and metabolic volume (MV) to diagnose metastasis in cases with enlarged lymph nodes (≥7 mm long in minor diameter) on contrast-enhanced CT. Two gastrointestinal surgeons intraoperatively identified target lymph nodes to assess the association between images and pathological findings. The diagnostic performance (i.e., sensitivity, specificity, and positive and negative predictive values) for lymph node metastasis was determined using multilevel logistic modeling. RESULTS: A total of 205 colorectal cancer patients were enrolled from February 2018 to April 2020 and 194 patients were analyzed in this study. The sensitivity, specificity, and positive and negative predictive values of PET-CT were 15.3% (13.4%-17.5%), 100.0% (99.0%-100.0%), 100.0% (51.2%-100.0%), and 98.7% (98.5%-99.0%), respectively. CONCLUSION: PET-CT is a useful modality for determining the presence of metastasis in swollen lymph nodes on contrast-enhanced CT in colorectal cancer patients.

Benefit of intensive chemotherapy for elderly patients aged 80 years or older with metastatic colorectal cancer: a state-wide multicenter cohort study.

BACKGROUND: It remains unclear whether intensive chemotherapy for Stage IV colorectal cancer (CRC) patients aged 80 years or older is beneficial prognostically. This study aimed to investigate the overall survival of Stage IV CRC patients aged ≥ 80 years receiving intensive chemotherapy. METHODS: The study design was a population-based, multicenter, historical cohort study. The extracted participants' data were consecutive patients diagnosed as Stage IV CRC between January 2008 and May 2015 in nine hospitals in Japan. Patients were classified into two groups according to age: aged group (≥ 80 years) and younger group (< 80 years old). Intensive chemotherapy was defined as at least two courses of doublet chemotherapy with oxaliplatin-or irinotecan-based regimens. The primary outcome was the adjusted hazard ratio (HR) of age ≥ 80 years in patients who undergoing intensive chemotherapy. RESULTS: During the study period, 1259 patients were treated for Stage IV CRC in the participating hospitals. In total, 231 patients (18.3%) were in the aged group, and 1028 (81.7%) were in the younger group, and 788 (62.6%) underwent intensive chemotherapy. The median overall survival for the aged and younger group patients was 21.0 months (interquartile range (IQR), 10.6-34.1 months) and 24.3 months (IQR 12.6-39.3 months), respectively. The adjusted HR of age ≥ 80 years was 1.29 (confidence intervals 0.84-2.00). CONCLUSION: Stage IV CRC patients aged 80 years or older receiving intensive chemotherapy had a similar prognosis to those aged < 80 years. Avoiding intensive chemotherapy for mCRC patients simply because they are ≥ 80 years old is not recommended.

Comparison of ethanol concentrations after drinking in patients who underwent total gastrectomy versus healthy controls.

BACKGROUND: The safety of drinking in patients who have undergone total gastrectomy for gastric cancer has not been established. We conducted a clinical trial to investigate the trend in alcohol absorption in actual patients. METHODS: Patients who received total gastrectomy with lymph-node dissection and Roux-en-Y reconstruction six or more months ago were enrolled. Participants drank 1 unit (20 g) of ethanol within 1 h starting at least 1 h after a meal. The blood alcohol concentration (BAC) was then estimated by a measurement of the breath alcohol concentration. The peak and trend in the BAC in patients was compared with that in healthy volunteers who were matched with patients for the alcohol-sensitive genotype. RESULTS: Ten patients and 10 healthy people were enrolled in the BAC evaluation. The peak BAC (%) was 0.158 in patients after total gastrectomy versus 0.110 in control (P < 0.001). The mean half-life of BAC was 58.0 min in the patient group and 94.0 min in the control group, although the mean time to complete drinking was significantly longer in the patient group than in the control group at 40.8 versus 21.9 min (P = 0.009). CONCLUSION: Drinking alcohol is likely to carry a risk of increasing the BAC in patients who have undergone total gastrectomy.

The effects of intensive oral care before surgery for gastric cancer patients.

OBJECTIVES: Oral function management has been recognized as important strategy for preventing postoperative complications. In this historical cohort study, we focused on the patients who planed gastrectomy, and investigated the appropriate duration and frequency of preoperative oral care to prevent complications after surgery. METHODS: Patients who planed surgery for gastric cancer between 2012 and 2018 were enrolled. We defined intensive oral care (IOC) as initial intervention at least three weeks before surgery and follow-up intervention within a week before surgery. As the primary outcome, the incidence of postoperative infectious complications was compared between the IOC and non-intensive oral care groups. RESULTS: A total of 576 patients were enrolled, including 66 with IOC. The incidence of infectious complications was 2/66 (3.0%) in the IOC group and 64/510 (12.5%) in the non-intensive oral care group. After adjusting for confounding factors, patients with IOC exposure had a lower chance of developing postoperative infectious complications (odds ratio; 0.217, 0.051-0.927). CONCLUSIONS: Intensive oral care can help prevent postoperative infectious complications after gastrectomy. These findings suggest that appropriate preoperative oral care includes at least two interventions: three weeks or more before and within one week before surgery.

The bacterial association with oral cavity and intra-abdominal abscess after gastrectomy.

BACKGROUND: Perioperative oral management has been reported to be effective for preventing postoperative infectious complications. In addition, severe periodontal disease was identified as the significant risk factor for complications after gastrointestinal surgery. We investigated the bacteriological association between the periodontal pocket, stomach mucosa and drainage fluid to determine whether oral bacteria directly cause intra-abdominal infection after gastrectomy. METHODS: Patients who were scheduled to undergo surgery for gastric cancer were prospectively enrolled. We evaluated the similarity of bacterial strains in periodontal pocket, stomach mucosa and fluid from drainage tube. Gingival crevicular fluid and dental plaque were collected from the periodontal pocket and cultured to detect bacteria. Specimens from the resected stomach were collected and used for bacterial culturing. Drainage fluid from the abdominal cavity was also cultured. RESULTS: All of 52 patients were enrolled. In the periodontal pocket, α-Streptococcus spp., Neisseria sp., and Prevotella sp. were mainly detected. Bacterial cultures in the stomach mucosa were positive in 26 cases. In 20 cases (76.9%), the detected strains were the same as those in the periodontal pocket. Six patients had the postoperative intra-abdominal infection after gastrectomy, and the same bacterial strains was detected in both of drainage fluid and periodontal pocket in two patients with severe periodontal disease. CONCLUSIONS: We found the bacteriological association that same strain detected in periodontal pocket, stomach and in intra-abdominal drainage fluid after gastrectomy in patients with periodontal disease.

The long-term outcomes in adolescent and young adult patients with colorectal cancer -A multicenter large-scale cohort study.

Introduction: The prognosis of adolescent and young adult (AYA) patients with colorectal cancer (CRC) is still unclear. The aim of this study was to investigate the clinical features and prognosis in AYA patients compared with middle- aged patients. Methods: Participants were identified from a clinical database of the multicenter cohort in Japan. The AYA group was defined as those <40 years of age, whereas the middle-aged group was defined in 10-year ranges around the median age of all patients. The primary outcome was the overall survival (OS), and the secondary outcome was the recurrence-free survival (RFS). Results: A total of 502 patients were enrolled as the AYA group, and 7222 patients between 65 and 74 years of age were identified as the middle-aged group. The OS of colon cancer in stages II and III was significantly better in the AYA group (p = 0.033, 0.006, respectively) than in the middle-aged groups. There were no significant differences in the OS of rectal cancer in stages II and III between the two groups. Conclusion: The prognosis of AYA patients with CRC was the same or better than that in middle-aged patients.

Characteristic Radiological Features of Retrospectively Diagnosed Pancreatic Cancers.

OBJECTIVES: The aim of this study was to assess the characteristic radiological features of early-stage pancreatic cancer (PC). METHODS: Between 2009 and 2016, 510 PC patients were selected from our hospital cancer registry database based on International Classification of Diseases for Oncology-3 (C25). Among them, 64 patients (42 males and 22 females; median age, 74 [range, 59-91]) had received repeated abdominal radiological examinations before their diagnosis of PC and were retrospectively investigated for specific radiological findings. The subjects underwent the following imaging examinations: computed tomography, magnetic resonance imaging, and fluoroglucose-positron emission tomography. RESULTS: Characteristic radiological features before diagnosis of PC were classified into the following 9 features: pancreatic duct ectasia (n = 16), focal low-density area (n = 15), change of cyst size (n = 8), localized tissue atrophy (n = 7), distal atrophy (n = 4), mass in pancreatic lipomatosis tissue (n = 2), mass concomitant with the already known cyst (n = 2), protrusion (n = 1), and parenchymal disproportion (n = 1). Fifty-three cases (84%) had more than one characteristic radiological feature before diagnosis of PC, and their median observation period until diagnosis was 24 (range, 1-120) months. CONCLUSIONS: The 9 characteristic radiological features provide an opportunity to diagnose PC at an early stage.

[The QOL Research in Gastric Cancer Treatment].

The quality of life(QOL)research for patients with gastric cancer still remains a room of development. Among some procedures of gastrectomy, we found few significant differences in QOL score reports but in symptoms' score in previous. Therefore, it is difficult for physicians to interpret or adapt the study results to their practice. QOL research also included several problems in study design or statistics, such as unmeasurable confounding factors, missing data management, control of type 1 error. The future issues are to establish the concept of gastric cancer specific QOL, to thoroughly investigate the optimal methodology to evaluate patients' QOL and to form consensus among researchers and patients.

Clinical impact of periodontal disease on postoperative complications in gastrointestinal cancer patients.

BACKGROUND: The effectiveness of perioperative oral management in gastrointestinal surgery remains unclear. To elucidate the clinical significance of oral care, we investigated the relationship between the oral environment and postoperative infectious complications (POICs) in patients undergoing gastrointestinal surgery. METHODS: This was a single-institute and historical cohort study of 341 patients. The participants were isolated from consecutive patients undergoing planned radical resection for gastrointestinal carcinoma from January 2016 to June 2017. Dentists assessed the oral environment for periodontal disease, hygiene status, dry mouth, fur on tongue, and tooth stumps. All patients received scaling and tooth brushing instructions. A stepwise logistic regression analysis was conducted to identify risk factors for POICs among the different oral statuses. RESULTS: The surgical procedures performed were gastrectomy in 123 (36.1%), colorectal resection in 185 (54.2%), and pancreatoduodenectomy or others in 38 (11.1%). POICs occurred in 48 patients (14.1%), including deep organ space infection in 20, surgical site infection in 11, anastomotic leakage in 5, urinary tract infection in 4, pneumonia in 2, and others in 6. After adjusting for confounding factors, periodontal disease was isolated as an independent risk factor for POICs (odds ratio 2.091, p = 0.037, 95% confidence interval 1.045-4.183). Other variables of oral environment such as hygiene status, dry mouth, fur on tongue, and tooth stumps did not have a significant impact on POICs. CONCLUSIONS: Periodontal disease is a risk factor for infectious complications after gastrointestinal surgery.

[Four Patients Who Underwent Proton Beam Therapy after Debulking Surgery and Omental Wrapping of the Residual Tumor as a Spacer for Unresectable Local Recurrence of Rectal Cancer].

We report 4 patients who underwent proton beam therapy after debulking surgery for unresectable local recurrence of rectal cancer. Case 1: A 55-year-old man underwent radiotherapy and systemic chemotherapy for local recurrence; however, the lesion exhibited evident regrowth. Combination therapy of debulking surgery, omental wrapping of the residual tumor as a spacer, and postoperative proton beam therapy was performed. He died of lung metastasis after 24 months. Case 2: A 79- year-old woman who underwent surgical resections and radiotherapy twice in a previous hospital was referred to our hospital. Similar to that in case 1, proton beam therapy after debulking surgery and omental wrapping was performed. She died of lymph node metastasis after 31 months. Case 3: A 75-year-old man was diagnosed with unresectable local recurrence of rectal cancer. He underwent combination therapy and is doing well without any recurrence for 43 months. Case 4: A 57-yearold woman was also diagnosed with unresectable local recurrence. She underwent the same combination therapy after systemic chemotherapy. She died of lymph node metastasis after 11 months.

Abscopal effect following radiation monotherapy in breast cancer: A case report.

Radiotherapy has been found to be valuable for the control and eradication of local foci in various malignant tumors. The abscopal effect is determined as a systemic antitumor response at a distance from the irradiation site invoked by local irradiation. We herein present an extremely rare case of breast cancer in a 64-year-old woman, in whom the abscopal effect was observed after radiotherapy induced an antitumor response in all metastatic lesions, without any combination therapy. The patient was admitted to our hospital complaining of a breast mass and pain at the left hip, and was diagnosed with breast cancer with multiple bone, lung and lymph node metastases. She received treatment with local radiotherapy delivered to the breast tumor and some of the bone metastases but did not receive chemotherapy due to her poor performance status. However, 10 months after radiotherapy, spontaneous regression was observed, not only within the irradiated field, but also in the non-irradiated areas. All signs of cancer throughout the body disappeared, and the patient's performance status drastically improved. To the best of our knowledge, there have been no reports of advanced breast cancer cases in which the abscopal effect was observed after radiation monotherapy; therefore, this case report is extremely rare and highly valuable.

[Indication for Radiotherapy for Breast Cancer Metastasis to the Skull Base Accompanied by Cranial Nerve Palsies].

Distant metastasis to the skull base region frequently manifests various cranial nerve symptoms and reduces patients' quality of life(QOL). We report a 62-year-old woman with skull base metastasis of breast cancer, whose condition clinically improved following palliative radiotherapy. The patient presented to our hospital with hoarseness. CT screening revealed a tumor in the right breast, axial lymph node swelling, and osteoblastic change at multiple sites. A core needle biopsy of the breast tumor revealed invasive lobular carcinoma. She also had nausea, anorexia, vertigo, lower left angle of the mouth, apraxia of lid closing, and dysphagia owing to several cranial nerve palsies. MRI T1- and T2-weighted images showed a diffuse low-signal intensity of the skull base region, and the patient was diagnosed as having breast cancer with symptomatic skull base metastases. Her cranial nerve symptoms improved after 1 week of palliative irradiation to the skull base. We conclude that, even among terminal-stage patients, palliative radiotherapy to the skull base region is an effective treatment option to improve patients' QOL.

Neuroendocrine tumor of the extrahepatic bile duct: A case report.

INTRODUCTION: Neuroendocrine tumors (NETs) of the extrahepatic bile ducts are extremely rare neoplasms arising from endocrine cells and have variable malignant potential. They most commonly occur in young females and usually present with painless jaundice. PRESENTATION OF CASE: Here we present the case of an asymptomatic 57-year-old woman with NET of the common bile duct that was incidentally discovered on abdominal ultrasound during a medical examination. She was admitted to our hospital with a diagnosis of hepatic hilar tumor. Computed tomography revealed the tumor surrounding the hepatic hilum and duodenum. Magnetic resonance cholangiopancreatography revealed a filling defect of the common bile duct with morphology suggestive of external compression. Endoscopic ultrasound confirmed a submucosal tumor of the duodenal bulb measuring 30×20mm in size. The patient qualified for surgery with a preoperative diagnosis of submucosal tumor of the duodenal bulb. Intraoperative examination revealed that the tumor location involved the common bile duct and/or cystic duct with no signs of invasion to other organs or metastatic lymph nodes. Excision of the biliary ducts and tumor was followed by Roux-en-Y anastomosis. Histological results showed NET grade 1. DISCUSSION: Preoperative diagnosis of NETs is difficult because of their rarity. A definitive diagnosis is usually established intraoperatively or after histopathological evaluation. CONCLUSION: For these tumors, surgical resection is currently the only treatment modality for achieving a potentially curative effect and prolonged disease-free survival.