Spontaneous rupture of an undifferentiated carcinoma with osteoclast-like giant cells of the pancreas presenting as intra-abdominal bleeding: a case report.

BACKGROUND: Undifferentiated carcinoma is a very rare histologic subtype, representing only 0.8% to 5.7% of all pancreatic exocrine neoplasms. Additionally, spontaneous abdominal hemorrhage is a particularly rare, life-threatening cause. CASE PRESENTATION: A 68-year-old man was taken by ambulance to our hospital because of sudden-onset abdominal pain. Contrast-enhanced abdominal computed tomography revealed a huge mass measuring 99 × 70 mm in the pancreatic tail with enhanced rim staining in the peripheral area. Imaging also showed extravasation and fluid collection beside the tumor. Hence, spontaneous rupture of the pancreatic tumor and intra-abdominal bleeding were diagnosed. Emergency laparotomy was performed because of acute abdominal pain with peritoneal signs. With an intraoperative diagnosis of rupture of the pancreatic tumor, distal pancreatectomy was successfully performed. Histologically, hematoxylin and eosin staining showed round to spindle-shaped, highly pleomorphic mononuclear cells and multinucleated giant cells as well as a component of ductal adenocarcinoma. Immunohistochemical staining showed that the tumor cells were negative for AE1/AE3, whereas the non-neoplastic osteoclast-like giant cells were positive for CD68. Taken together, these results led to a diagnosis of undifferentiated carcinoma with osteoclast-like giant cells. The patient's postoperative course was uneventful. CONCLUSION: We experienced an extremely rare case of spontaneous rupture of an undifferentiated carcinoma with osteoclast-like giant cells presenting as intra-abdominal bleeding. Obtaining a correct preoperative diagnosis is quite difficult at the first evaluation. Undifferentiated carcinoma should be considered as a differential diagnosis in the case with spontaneous rupture of a pancreatic tumor.

[Fracture of a Gastrointestinal Stent during Chemotherapy for Unresectable Advanced Gastric Cancer-A Case Report].

A 79-year-old man with shortness of breath on exertion had right pleural effusion and ascites effusion on CT, and was diagnosed with adenocarcinoma on pleural cytology. Upper gastrointestinal endoscopy revealed a gastric cancer with pyloric stenosis, and biopsy from the same site revealed Group 5(tub2). The patient was diagnosed as unresectable advanced gastric cancer with pyloric stenosis and peritoneal and pleural dissemination. After placement of an uncovered metallic stent for the pyloric stenosis, SOX therapy was started. Three months after stent placement, a CT scan to determine the effect of chemotherapy showed stenosis in the gastrointestinal stent, partial breakage of the stent on the mouth side, and prolapse of the stent into the stomach. There were no symptoms such as abdominal pain, and the patient was placed on standby for retrieval of the dislodged stent. The prolapsed stent was retrieved endoscopically, and a covered metallic stent was additionally implanted as a"stent in stent". The patient has had no further passage obstruction and is currently undergoing chemotherapy. We report a case of fracture of a gastrointestinal stent during chemotherapy for unresectable advanced gastric cancer.

Successful resection of a huge hepatocellular adenoma.

Hepatocellular adenoma (HCA) is a rare benign liver tumor that has been reported to occur particularly more often in women who use contraceptives. A 72-year-old woman with no history of using contraceptives presented to our hospital for further examination of a liver tumor. Contrast-enhanced computed tomography and gadoxetic acid-enhanced magnetic resonance imaging revealed a huge solitary hepatic tumor measuring 83 × 76 mm in segments 4, 5, and 8. The differential diagnoses were cholangiocarcinoma and mixed-type hepatocellular carcinoma. Percutaneous needle biopsies were performed twice, and no malignant components were found. Central bi-segmentectomy of the liver was successfully performed. Immunohistochemical staining showed that ß-catenin was positive in the membrane of the tumor cells, while fatty acid-binding protein, glutamine synthetase, and amyloid A were negative. These results led to a diagnosis of HCA, hepatocyte nuclear factor-1α-inactivated subtype. The patient's postoperative course was uneventful, and she developed no recurrence for 10 months after surgery. We experienced a rare case of benign HCA. Obtaining a correct preoperative diagnosis is sometimes difficult at the first evaluation. HCA should be considered as a differential diagnosis of liver tumors.

Synchronous gastric cancer and primary lymphoma of right adrenal gland: a case report.

This report presents an extremely rare case of synchronous gastric cancer and primary adrenal diffuse large B-cell lymphoma (DLBCL). An 82-year-old man underwent computed tomography, which revealed a heterogeneous appearing and hypodense adrenal mass and a gastric mass with no enlarged lymph nodes in the neck, mediastinum, abdomen, and inguinal region. Upper gastrointestinal endoscopy revealed a protruding gastric tumor. The specimens obtained from endoscopic biopsy were histologically confirmed to be adenocarcinoma. The hormonal findings eliminated functional adrenal tumor. The patient underwent distal gastrectomy with regional lymph node resection for gastric cancer and incisional biopsy of the adrenal mass. Based on the pathological findings, diagnoses of mixed mucinous and tubular adenocarcinomas of the stomach and adrenal DLBCL were confirmed. Postoperation, the patient received rituximab combined with low-dose doxorubicin, cyclophosphamide, vincristine, and prednisone (R-miniCHOP). Six courses of R-miniCHOP were planned, but were completed in only one course at the patient's request. The patient died 2 months after surgery.

Postoperative solitary liver metastasis from esophageal squamous cell carcinoma achieving a clinical complete response to chemotherapy with cisplatin and 5-fluorouracil followed by stereotactic body radiotherapy: A case report.

Treatment strategies for distant organ metastasis have changed markedly since the concept of oligometastasis was introduced. The perception that distant organ metastasis is a systemic disease and not eligible for local therapy is now a thing of the past. Therefore, the present report details a case of postoperative solitary liver metastasis from esophageal squamous cell carcinoma (ESCC), which achieved a clinical complete response to chemotherapy with cisplatin and 5-fluorouracil (5-FU) followed by stereotactic body radiotherapy (SBRT). A 76-year-old male patient underwent esophagectomy for lower thoracic ESCC. At 7 months after surgery, abdominal CT revealed a solitary hypovascular mass, 28 mm in size, in segment 7 of the liver. After three courses of chemotherapy with cisplatin and 5-FU, abdominal CT revealed that the liver mass had shrunk to 7 mm in size. SBRT was then administered with a 6 MV X-ray beam generated by a linear accelerator. A total dose of 50 Gy was given in 5 fractions of 10 Gy to the liver mass. At 1 month after SBRT, abdominal CT revealed that the liver mass had disappeared. The patient received no further adjuvant chemotherapy and had no recurrence at 18 months after diagnosis of liver metastasis and 13 months after SBRT.

[Small Bowel Metastasis of Breast Cancer-A Case Report].

A 69-year-old female had hormone therapy for liver metastasis after surgery for right breast cancer. She came to the hospital with a complaint of abdominal pain and was admitted with a diagnosis of small bowel obstruction. She had previously undergone surgery for an ovarian tumor and was suspected of having an intestinal obstruction caused by adhesions in her pelvis. She promptly improved with conservative treatment of fasting only. In the following months, she developed 2 intestinal obstructions, and CT scan revealed a neoplastic lesion in the small intestine. With the diagnosis of small intestinal tumor, laparoscopic surgery was performed. A neoplastic lesion was found in the ileum. A small bowel resection was performed. She was discharged with a good postoperative course. The pathological results showed breast cancer metastasis in the small intestine. Based on the diagnosis, postoperative chemotherapy has been started. Gastrointestinal metastasis of breast cancer is relatively rare and rarely causes clinical problems. We report a case of small intestinal metastasis of breast cancer.

Successful management of gastric remnant necrosis after proximal gastrectomy using a double elementary diet tube: a case report.

BACKGROUND: The stomach has many incoming vessels and is resistant to ischemia due to the rich microvascular network within its submucosal layer. Although reports of gastric remnant necrosis after gastrectomy have been rare, mortality rates remain substantially high when present. A double elementary diet (W-ED) tube, which can be used for both enteral feeding and gastrointestinal tract decompression, has been developed for anastomotic leakage and postoperative nutritional management after upper gastrointestinal surgery. The current report presents a case of gastric remnant necrosis after proximal gastrectomy that was successfully managed through conservative treatment with a W-ED tube. CASE PRESENTATION: A 73-year-old male was referred to our hospital for an additional resection after endoscopic submucosal dissection (ESD) for gastric cancer. Endoscopic findings showed an ESD scar on the posterior wall of the upper portion of the stomach, while computed tomography (CT) showed no obvious regional lymph node enlargement and distant metastases. The patient subsequently underwent laparoscopic proximal gastrectomy and esophagogastrostomy but developed candidemia on postoperative day 7. On postoperative day 14, endoscopy revealed gastric ischemic changes around the anastomotic site, suggesting that the patient's candidemia developed due to gastric necrosis. His vital signs remained normal, while the gastric remnant ischemia was localized. Given that surgery in the presence of candidemia was considered extremely risky, conservative treatment was elected. A W-ED tube was placed nasally, after which enteral feeding was initiated along with gastrointestinal tract decompression. Although the patient subsequently developed anastomotic leakage due to gastric remnant necrosis, local control was achieved and conservative treatment was continued. On postoperative day 52, healing of the gastric remnant necrosis and anastomotic leakage was confirmed, after which the patient started drinking water. Although balloon dilation was required due to anastomotic stenosis, the patient was able to resume oral intake and was discharged on postoperative day 88. CONCLUSIONS: Herein, we present our experience with a case of gastric remnant necrosis after proximal gastrectomy, wherein conservative management was achieved using a W-ED tube. In cases involving high operative risk, the management should be mindful of gastric remnant necrosis as a post-gastrectomy complication.

Successful resection of a neuroendocrine tumor in the gallbladder: a case report.

BACKGROUND: Gallbladder neuroendocrine tumors (GB-NETs) are extremely rare, representing only 0.5% of all NETs because no neuroectodermal cells are present in the gallbladder. In 2019, the World Health Organization updated the classification of NETs based on their molecular differences. The mutation status of DAXX and ATRX has been added to the criteria for well-differentiated NETs. CASE PRESENTATION: A 50-year-old man presented to our hospital for further examination of a gallbladder polyp. He had no right quadrant pain, fever, jaundice, weight loss, or carcinoid syndrome-related symptoms. The patient hoped to avoid cholecystectomy. During the 3-year observation period, the polyp gradually increased in size from 8.3 to 9.9 mm. He decided to undergo surgery, and whole cholecystectomy was successfully performed. Immunohistochemical staining revealed positivity for chromogranin A, synaptophysin, and CD56. The Ki-67 index was < 3%. Taken together, these results led to a diagnosis of a grade 1 GB-NET. We also performed immunohistochemical staining of DAXX and ATRX, which revealed that DAXX protein expression was negative. The patient's postoperative course was uneventful, and he developed no recurrence for 8 years after surgery. CONCLUSION: We experienced a very rare case of GB-NET. Obtaining a correct preoperative diagnosis is quite difficult at the first evaluation. A GB-NET should be considered as a differential diagnosis of gallbladder tumors.

Occult follicular lymphoma in a swollen regional lymph node of gastric schwannoma.

BACKGROUND: Regional lymphadenopathy is more commonly noted in gastric schwannomas than in other gastric submucosal tumors. Most of the swollen lymph nodes associated with gastric schwannomas are non-metastatic lymphadenopathy. CASE PRESENTATION: A 69-year-old Japanese woman was referred to our hospital with a chief complaint of abdominal discomfort. Contrast-enhanced computed tomography (CT) of the abdomen revealed an extraluminal tumor with heterogeneous enhancement at the middle stomach on the lesser curve, accompanied with one swollen lymph node approximately 10 mm in size and several small lymph nodes in the perigastric region. These lymph nodes were flat; therefore, we considered them to be non-metastatic. The main tumor was removed via wedge resection. Soft and slightly swollen lymph nodes, which were compatible with the lymph nodes noted in the preoperative CT, were found near the main tumor in the fatty tissue at the lesser curvature of the stomach. An excisional biopsy of the largest lymph node was performed for the diagnosis. Based on pathological findings, a diagnosis of gastric schwannoma and follicular lymphoma (FL) was confirmed. The patient is doing well without recurrence of either the gastric schwannoma or FL 28 months postsurgery. CONCLUSIONS: The present report detailed an extremely rare case of FL coincidentally discovered in the swollen regional lymph node of gastric schwannoma.

A Case of Pathological Complete Response Following FOLFIRINOX Therapy for Pancreatic Adenocarcinoma with Synchronous Distant Lymph Node Metastases.

INTRODUCTION: We report a case of conversion surgery for pancreatic ductal adenocarcinoma (PDAC) with synchronous distant metastases showing pathological complete response (pCR) after FOLFIRINOX therapy. PRESENTATION OF CASE: A 46-year-old woman with obstructive jaundice was referred to our hospital. A CT scan revealed a hypo-vascular mass in the head of the pancreas with multiple para-aortic lymph nodes and a Virchow's node swollen. The serum CA 19-9 level was 71795.1 U/mL. The result of tumor biopsy from the biliary stenotic site was concordant with adenocarcinoma. She was diagnosed with PDAC with distant metastases. After 10 courses of FOLFIRINOX followed by 4 courses of FOLFIRI, a CT scan showed that distant lymph node swellings disappeared, and CA19-9 level became almost normal. She underwent pancreaticoduodenectomy with dissection of para-aortic lymph nodes 8 months after the initiation of chemotherapy. Pathologically, no evidence of residual adenocarcinoma was observed in neither pancreas nor lymph nodes. Adjuvant chemotherapy using S-1 was administered for 6 months, and no recurrence has been observed 4 years after surgery. BRCA1/2 mutations were not detected in patient's DNA. DISCUSSION: With the induction of intensive chemotherapies such as FOLFIRINOX, an increasing number of patients with synchronous distant metastases could become suitable candidates for surgery of the primary lesion because of the potential complete response of metastatic lesions. CONCLUSION: This case presented a rare occurrence of pCR in a patient with unresectable PDAC with distant metastases who received FOLFIRINOX. The feasibility and benefits of conversion surgery in such patients must be investigated in future trials.

Isolated myeloid sarcoma presenting with small bowel obstruction: a case report.

BACKGROUND: Myeloid sarcoma (MS) is a solid tumor consisting of myeloid blasts or immature myeloid cells, which are unusual outside the bone marrow. CASE PRESENTATION: We present a rare case of isolated myeloid sarcoma of the small bowel in a 54-year-old man who was admitted to our hospital with repeated symptoms of intestinal obstruction. A small bowel series via an ileus tube revealed severe jejunal obstruction. Computed tomography revealed that the obstruction was likely caused by a jejunal tumor. The patient underwent laparoscopy-assisted partial resection of the jejunum with lymphadenectomy. Histopathological examination of the surgical specimen confirmed that MS had been responsible for the obstruction. CONCLUSIONS: Patients with MS require systemic chemotherapy, as do patients with acute myeloid leukemia. Hence, an early, accurate diagnosis is imperative for treating this malignancy. It is also important to list MS in the differential diagnosis of a small bowel tumor, even in nonleukemic patients.

[Right Hemicolectomy and Pancreatoduodenectomy for Transverse Colon Cancer Invasion to the Duodenum-A Case Report].

A 74-year-old woman visited her local doctor with stomach ache and weight loss. Abdominal ultrasonography showed a mass in the hepatic flexure of the transverse colon. She was referred to our hospital. Colonoscopy revealed transverse colon cancer in the hepatic flexure. Upper endoscopy showed redness of the mucosa and stenosis in the descending portion of the duodenum. Therefore, duodenal invasion was suspected. The CT scan showed a regional lymph node metastasis, but there were no obvious signs of distant metastases. From the aforementioned findings, we diagnosed the patient with duodenal invasion of transverse colon cancer(cT4b, N1, M0, cStage Ⅲ). There was no intraoperative peritoneal dissemination or liver metastasis, and we performed right hemicolectomy and pancreatoduodenectomy for transverse colon cancer. On histopathological examination, we diagnosed pT4b(Duo, Pan), N1b(3/35), M0, pStage Ⅲb. The patient had delayed gastric emptying after surgery. She recovered conservatively and was discharged on POD 37. She underwent adjuvant chemotherapy( capecitabine therapy)and has been alive without recurrence 8 months after surgery. In some cases of colon cancer invasion of other organs, long-term survival can be achieved if R0 resection is possible, and we should consider extended resection.

[A Resected Case of Angiomyolipoma Difficult to Be Distinguished from Hepatocellular Carcinoma].

A 42-year-old man complaining of left back pain was admitted to our hospital. The hepatis B and C surface antigens were negative. The serum levels of tumor markers were within the reference ranges. Abdominal ultrasound revealed an 8 cm-sized, primarily round and hyperechoic mass in the left lateral segment. Contrast-echo showed non-uniform enhancement in the arterial phase and uniform enhancement in the portal phase. This mass did not indicate"wash-out"on contrast- enhanced CT. It showed hypointensity in the hepatobiliary phase on MRI. The definitive diagnosis could not be obtained, and the patient was suspected with malignancy, such as hepatocellular carcinoma(HCC). Therefore, left hemi-hepatectomy was performed for the diagnostic treatment. Based on the immunochemical staining results, he was diagnosed with angiomyolipoma( AML). AML is composed of fat, blood vessels, and smooth muscles. It is regarded as a tumor of perivascular epithelioid cell tumor(PEComa). Early venous return and adipose tissues in the tumor were the distinctive features of this tumor. The preoperative diagnosis of AML without any fatty component as in this case is very difficult.

[A Case of Resected Peritoneal Metastasis from Hepatocellular Carcinoma after Surgery].

A 69-year-old woman with a hepatocellular carcinoma(HCC)was followed-up for type B chronic hepatitis and underwent partial hepatectomy(S6)at our hospital. Afterwards, she underwent radiofrequency ablation(RFA)therapy twice because of intrahepatic recurrence. Seven months after the first hepatectomy, a left adrenalectomy was performed for a left adrenal metastasis. Seventeen months after the first hepatectomy, a splenectomy was performed for a splenic metastasis. Forty-three months after the first hepatectomy, a second hepatectomy was performed for intrahepatic recurrence, and a right adrenalectomy was performed for an adrenal metastasis. Sixty-eight months after the first hepatectomy, an abdominal CT revealed a growing solitary lesion in the ascending colon, which was diagnosed as a peritoneal metastasis. The peritoneal dissemination was removed because there were no other extrahepatic or intrahepatic recurrences. Histologically, the resected specimen was diagnosed as a peritoneal metastasis from a HCC. The patient survived, and there were no recurrences for 6 months after the operation. We report this case of a peritoneal metastasis from a HCC after surgery with a review of the literature.

[AFP and PIVKA-â ¡ Producing Gastric Cancer with Metachronous Liver Metastasis after Gastrectomy-A Case Report].

A 67-year-old man visited his doctor because of anorexia and was diagnosed with gastric cancer based on endoscopic findings. Endoscopy revealed a 0-Ⅰ type tumor, 6 cm in size, at the gastric angle. Preoperative CT showed no apparent lymph node or distant metastases. Distal gastrectomy was performed for gastric cancer with Billroth Ⅰ reconstruction. He had no complications and was discharged on postoperative day 11. The pathological Stage was pT2N0M0, pStage ⅠB, and he underwent no adjuvant chemotherapy. Four months postoperatively, serum CA19-9, AFP, and PIVKA-Ⅱ were elevated, and CT revealed multiple liver tumors. A liver biopsy was performed for the definitive diagnosis. The patient was diagnosed with liver metastases from gastric cancer. It is considered that AFP and PIVKA-Ⅱ were produced by the liver metastasis from gastric cancer. He received chemotherapy for liver metastasis and died 1 year after the recurrence.

[Outcomes of FOLFIRINOX as First-Line Treatment for Recurrent or Unresectable Pancreatic Cancer].

We retrospectively analyzed adverse effects(AEs), overall survival(OS), and progression-free survival(PFS)in 15 consecutive patients treated with FOLFIRINOX as the first-line treatment for recurrent or unresectable pancreatic ductal adenocarcinoma( PDAC)between February 2014 and December 2017 in our hospital. Eleven patients were treated for unresectable PDAC with distant metastases(UR-M), and 4 were treated for locally advanced unresectable PDAC(UR-LA). The median age was 56(range: 40-75)years. Nine patients were male, and 6 were female. The performance status was 0 or 1 in all patients. Tumors were located in the pancreas head in 8 cases and in the body-tail in 7 cases. Grade 5 AEs were observed in 1 case in which liver abscess causing sepsis resulted in mortality. The response rate was 20.0%, and the disease control rate was 66.7%. Two patients underwent conversion surgery after FOLFIRINOX treatment. Seven patients received a nab-paclitaxel plus gemcitabine regimen as second-line treatment. The median OS and PFS were 17.0 and 8.4 months, respectively, and the 1-year survival rate was 66.7%. FOLFIRINOX for recurrent and unresectable PDAC showed relatively good tumor control. However, strict attention is required for severe AEs. Conversion surgery might be effective in patients who are good responders even if they have metastatic disease.

Efficacy and safety of anticoagulant prophylaxis for prevention of postoperative venous thromboembolism in Japanese patients undergoing laparoscopic colorectal cancer surgery.

AIM: To investigate the efficacy and safety of anticoagulant prophylaxis to prevent postoperative venous thromboembolism (VTE) during laparoscopic colorectal cancer (CRC) surgery, which is unknown in Japanese patients. METHODS: We conducted this randomized controlled trial at nine institutions in Japan from 2011 to 2015. It included 302 eligible patients aged 20 years or older who underwent elective laparoscopic surgery for CRC. Patients were randomly assigned to an intermittent pneumatic compression (IPC) therapy group or to an IPC + anticoagulation therapy group. Anticoagulation therapy comprised fondaparinux or enoxaparin for postoperative VTE prophylaxis. Postoperative VTE was diagnosed based on enhanced multi-detector helical computed tomography. The primary endpoint was VTE incidence, including asymptomatic cases, the secondary endpoint was incidence of major bleeding, and we conducted an intention-to-treat analysis. This study is registered in UMINCTR (UMIN000008435). RESULTS: Postoperative VTE incidence was 5.10% with IPC therapy (n = 157) and 2.76% with IPC + anticoagulant therapy (n = 145; P = .293). We identified no symptomatic VTE cases. The major bleeding rates were 1.27% with IPC alone and 1.38% with the combination (P = .936). The overall bleeding rates were 7.69% for enoxaparin and 13.6% for fondaparinux (P = .500), and there were no bleeding-related deaths. CONCLUSION: Anticoagulant prophylaxis did not reduce the incidence of VTE and the incidence of major bleeding was comparable between the two groups. Usefulness of perioperative anticoagulation was not demonstrated in this study. Pharmacological prophylaxis must be restricted in Japanese patients with higher risk of VTE.

Clinical significance of preoperative chemoradiotherapy for advanced esophageal cancer, evaluated by propensity score matching and weighting of inverse probability of treatment.

The present study used inverse probability of treatment weighting (IPTW) and propensity score matching (PSM) to compare survival benefits among 112 patients with resectable, stage II-IV esophageal squamous cell carcinoma (SCC) treated between 1996 and 2016 with neoadjuvant chemoradiotherapy (NAC) plus surgery (Group A, n=55) or with surgery alone (Group B, n=57). Their propensity scores (PS) were calculated using a multivariable logistic regression model in which age, sex, cancer site, primary tumor length, cTNM stage, lymph node metastasis and depth of tumor invasion were the independent variables, and used to match Groups A and B according to the IPTW and matching method. After IPTW and PSM, univariate analysis was used to assess overall survival (OS) and disease-free survival (DFS), followed by Cox proportional hazard models for OS using IPTW between the two groups and the subgroups. After PSM, 5-year OS and DFS were significantly higher in Group A (OS: 65.2%, DFS: 65.2%) compared with Group B (OS: 31.2%, DFS: 20.87%). Similarly, after IPTW, OS and DFS were significantly higher in Group A compared with Group B patients. Five-year OS was 73.18% for Group A and 37.69% for Group B (hazard ratio: 0.2899, 95% confidence interval: 0.1167-0.7205). To conclude, treatment was more effective in Group A patients with clinical stage II, N0 and T3 disease involving the mid-esophagus. It was concluded that for patients with esophageal SCC, NAC plus esophagectomy exhibited improved survival compared with surgery alone, as demonstrated by use of IPTW and PSM methods.

Solid pseudopapillary neoplasm of the pancreas showing marked distal atrophy: A case report.

INTRODUCTION: Solid pseudopapillary neoplasm (SPN) of the pancreas is a rare neoplasm, affecting primarily young females. Because SPNs are of low-malignancy, they rarely obstruct the main pancreatic duct (MPD) and cause atrophy of the distal pancreas even if their tumor sizes are large. PRESENTATION OF CASE: A 35-year-old female was referred to our hospital due to pancreatic tumor. Imaging findings showed the presence of well-defined round tumor in the body of the pancreas with 25-mm in diameter. The pancreas parenchyma distal to the tumor was markedly atrophic, and MPD dilatation was not observed. The lesion was diagnosed as SPN by endoscopic ultrasound-guided fine needle aspiration (EUS-FNA), and central pancreatectomy was performed. Intraoperative frozen section of the distal atrophic pancreas showed no evidence of acinar cells, indicating exocrine dysfunction. Therefore, we closed distal pancreas stump instead of reconstruction. In the distal atrophic parenchyma, scattered foci of islets of Langerhans and the vestige of dilated MPD were observed. She has shown neither endocrine nor exocrine insufficiency after surgery. DISCUSSION: SPNs are usually found without atrophic change of distal pancreas. To the best of our knowledge, this is the first report of SPN in which exocrine dysfunction of atrophic pancreas was demonstrated pathologically and central pancreatectomy without anastomosis of distal pancreas was chosen for the surgical treatment. CONCLUSION: We reported a very rare case of SPN with marked distal parenchymal atrophy. We successfully performed central pancreatectomy without reconstruction.

Thymidylate synthase expression in primary colorectal cancer as a predictive marker for the response to 5-fluorouracil- and oxaliplatin-based preoperative chemotherapy for liver metastases.

In patients with colorectal liver metastases (CRLM), predictive markers for response to preoperative chemotherapy are lacking. The aim of the present study was to evaluate the expression of thymidylate synthase (TS) and excision repair cross-complementation group 1 (ERCC1) as predictive markers in CRLM. A total of 24 patients with CRLM were included in this study. Tumor response was evaluated using the tumor regression grade (TRG) and Response Evaluation Criteria in Solid Tumors (RECIST) methods. TS and ERCC1 expression in paired CRLM and primary lesions were assessed by immunohistochemistry. We analyzed correlations between i) the response to preoperative chemotherapy evaluated by TRG and RECIST, ii) TS and ERCC1 expression and the response evaluated by TRG and RESICT, and iii) TS and ERCC1 expression in matched pairs of primary tumor and CRLM. The preoperative chemotherapy response evaluated by TRG and RECIST was significantly associated (P=0.0005). The response based on RECIST criteria and TRG was significantly associated with TS expression in the primary tumor (P=0.0272, and P=0.0137, respectively). No correlations were detected between marker expression in the primary tumor and in CRLM for either TS or ERCC1 (P=0.371 and P=1.00, respectively). Our data suggested that TS expression in the primary tumor is a predictive marker of preoperative chemotherapy response in CRLM based on both TRG and RECIST methods.