Spontaneous regression of transverse colon cancer with high-frequency microsatellite instability: a case report and literature review.

BACKGROUND: Spontaneous regression (SR) of colorectal cancer (CRC) is extremely rare, and only few cases have been reported. Although it is not yet clarified, a plausible mechanism for SR of CRC is an immunological event. CASE PRESENTATION: In this report, we present the case of SR of primary CRC in a 78-year-old man. Preoperative colonoscopy was performed, and a type 2 tumor measuring 30 mm in diameter in the transverse colon was detected. The biopsy revealed a poorly differentiated adenocarcinoma. Colectomy was performed 2 months after initial colonoscopy. During the surgery, only a 10-mm ulcer harboring a polypoid lesion measuring 8.5 mm was detected in the resected tissue; no other masses or carcinoma cells were seen on histological examination. Afterwards, the biopsy specimens were reanalyzed, and immunohistological analysis verified this as adenocarcinoma with stroma-infiltrating lymphocytes. Further analysis revealed a loss of two mismatch repair proteins, suggesting sporadic high-frequency microsatellite instability (MSI-H). CONCLUSION: According to previous literature, a common site of SR in CRC is the proximal colon, which is a feature of MSI-H CRC. However, our report showed a rare case of SR of CRC, which was in the transverse colon, with MSI-H present. This report indicates a relationship between immunological features of MSI-H and the occurrence of SR of CRC. A better understanding of this phenomenon and the mechanisms involved will have significant preventive and therapeutic implications for CRC, including anti-PD-1 immune checkpoint inhibitor therapy.

[A case of lung cancer with small intestine metastasis with perforative peritonitis as the initial symptom].

Herein, we report a case oflung cancer with metastasis to the small intestine, with perforative peritonitis as the initial symptom. An 82-year-old man who had undergone subtotal gastrectomy and Roux-en-Y anastomosis for gastric cancer 8 years previously was admitted to our hospital with abdominal pain. We diagnosed the patient with gastrointestinal perforation, and a chest computed tomography(CT)scan showed a mass in the right lung. A laparotomy revealed a 4×3 cm sized intestinal tumor and intestinal perforation in the immediate vicinity ofthe anastomotic site. Segmentectomy ofthe small intestine was performed. Histological examination indicated that the tumor specimen was squamous cell carcinoma. Four months later, an abdominal CT scan showed multiple liver metastases, and the patient died 6 months after the operation because ofcachexia. At autopsy, a diagnosis ofsmall intestine metastatic tumor originating from squamous cell carcinoma of the lung was made. Although small intestine metastasis from lung cancer is rare, it should be considered when progressive abdominal symptoms are observed.

[A case of advanced gastric cancer effectively treated with weekly paclitaxel as neoadjuvant chemotherapy].

We report a patient with advanced gastric cancer responding remarkably to neoadjuvant chemotherapy consisting of weekly paclitaxel. The patient was a 50-year-old male who had large advanced gastric cancer, suspected of invasion to the duodenum and pancreas and severe lymph node metastasis [cT4 (pancreas), cN2, cH0, cP0, cM0, cStage IV]. He was treated with weekly paclitaxel as neoadjuvant chemotherapy. According to gastroscope and CT findings, a significant tumor reduction was obtained after 3 courses. Therefore, distal gastrectomy with D2 nodal dissection were performed. The histological diagnosis was pT2, pN2, pStage IIIA, and the histological effect of the main tumor was judged to be Grade 2. The patient has now been in good health without recurrence for 3 years after surgery. This case suggests that neoadjuvant chemotherapy with weekly paclitaxel is a potentially effective regimen for advanced gastric cancer.

Locally advanced gallbladder cancer treated with effective chemotherapy and subsequent curative resection: a case report.

BACKGROUND: Surgical resection of gallbladder cancer with negative margins is the only potentially curative therapy. Most patients with gallbladder cancer are diagnosed in an advanced stage and, despite the availability of several chemotherapies, the prognosis remains dismal. We report a case of locally advanced gallbladder cancer that was successfully treated with effective cisplatin plus gemcitabine, followed by curative resection. CASE PRESENTATION: A 55-year-old Japanese female was hospitalized with right hypochondrial pain. Enhanced computed tomography revealed a 49 × 47 mm mass at the neck of the gallbladder, with suspected invasion of the liver and right hepatic artery. Endoscopic retrograde cholangiopancreatography demonstrated displacement of the upper bile duct. Intraductal ultrasonography showed irregular wall thickening and disappearance of the wall structure in bile ducts from the B4 branch to distal B2 and B3. Percutaneous transhepatic biliary biopsy revealed a poorly differentiated carcinoma. The patient was diagnosed with unresectable gallbladder cancer (T4N0M0 stage IVA). Cisplatin plus gemcitabine chemotherapy was initiated. After six courses of chemotherapy, enhanced computed tomography showed that the mass in the neck of the gallbladder had shrunk to 30 mm, Endoscopic retrograde cholangiopancreatography showed improvement of the hilar duct stenosis. A biopsy of the bile duct mucosa showed no malignant cells in the branch of the left and right hepatic ducts, the left hepatic duct, or the intrapancreatic ducts. The patient underwent conversion surgery with right and segment 4a liver resection, extrahepatic duct resection, and cholangiojejunostomy. The histopathologic diagnosis showed that the tumor cells had shrunk to 2 × 1 mm, and that R0 resection of the T2aN0M0 stage IIA tumor was successful. CONCLUSION: Although conversion surgery for gallbladder cancer is rarely possible, curative resection may offer a better prognosis, and it is important to regularly pursue possibilities for surgical resection even during chemotherapy.

A duodenal gastrointestinal stromal tumor mimicking a pancreatic neuroendocrine tumor: a case report.

BACKGROUND: Duodenal gastrointestinal stromal tumors are rare. If tumor growth is extraluminal and involves the head of the pancreas, the diagnosis of a duodenal gastrointestinal stromal tumor is difficult. CASE PRESENTATION: A 44-year-old Japanese woman was referred to our hospital with anemia. An enhanced computed tomography scan showed a hypervascular mass 30 mm in diameter, but the origin of the tumor, either the duodenum or the head of the pancreas, was unclear. Upper gastrointestinal endoscopy revealed bulging accompanied by erosion and redness in part of the duodenal bulb. Mucosal biopsy was not diagnostic. Endoscopic ultrasound fine-needle aspiration was difficult to perform because a pulsating blood vessel was present in the region to be punctured. These findings led to a diagnosis of pancreatic neuroendocrine tumor invasion to the duodenum. The patient underwent pancreaticoduodenectomy. Histologically, the tumor was made up of spindle-shaped cells immunohistochemically positive for c-Kit and CD34. The tumor was ultimately diagnosed as a duodenal gastrointestinal stromal tumor. CONCLUSION: Extraluminal duodenal gastrointestinal stromal tumors are rare and mimic pancreatic neuroendocrine tumors. Endoscopic ultrasound fine-needle aspiration is useful for preoperative diagnosis, but it is not possible in some cases. Intraoperative diagnosis based on a completely resected specimen of the tumor may be useful for modifying the surgical technique.

Surgical treatment of hepatic xanthogranuloma arising from a giant hepatic cyst causing gastrointestinal obstruction: a case report.

Hepatic cysts are benign liver lesions and are often asymptomatic. Large hepatic cysts may cause jaundice and portal hypertension; however, they rarely cause gastrointestinal obstruction. Symptomatic cysts require treatment, and when malignancy is suspected, cyst puncture for pathological examination of the fluid may pose a risk of dissemination. Herein, we describe a case of xanthogranuloma arising from a large hepatic cyst that was causing duodenal obstruction. Thus, cyst puncture was performed for emergency decompression. Cytological examination of the puncture fluid revealed no malignant findings. Hence, laparoscopic deroofing was performed to treat the hepatic cyst. As the cyst and duodenal wall were firmly adherent, the cyst wall was left behind without dissection from the duodenum. A two-stage approach of cyst puncture followed by surgery may be an option for patients requiring urgent treatment for potentially malignant hepatic cysts.

A Case of Stage II Ascending Colon Cancer with Cardiac Tamponade Due to Pericardial Metastasis.

BACKGROUND Malignant tumors, such as lung and breast cancers, can metastasize to the heart. However, cardiac metastasis rarely occurs in colorectal cancer. Cardiac metastasis cases are typically asymptomatic and rarely cause cardiac tamponade. Heart failure due to systemic metastasis is a terminal symptom; therefore, cardiac metastasis is rarely diagnosed when a patient is alive. We report a case of stage II ascending colon cancer with cardiac tamponade due to pericardial metastasis. CASE REPORT The patient was a 63-year-old woman who underwent laparoscopic ileocecal resection for ascending colon cancer. The final pathological diagnosis was stage IIB cancer. At the time of surgery, computed tomography scans revealed no metastases to the regional lymph nodes, liver, lungs, and other organs. The patient was then referred for dyspnea 5 months after the surgery. Computed tomography revealed large quantities of pericardial effusion, and the patient was diagnosed with cardiac tamponade. The symptoms were alleviated after pericardiocentesis. Cytological examination of the pericardial fluid confirmed the diagnosis of adenocarcinoma, and by extension, cardiac metastasis of the ascending colon cancer. Anticancer agents were recommended, but the patient opted for palliative treatment. CONCLUSIONS We report a rare case of ascending colon cancer with pericardial metastasis. The advancements in chemotherapy have made the prognosis of colorectal cancer more favorable. The prevalence of pericardial metastasis is expected to increase as well. As such, it is necessary to discuss similar case encounters and establish appropriate treatment.

Synchronous gastric cancer and carcinoma in situ of the pancreas.

Abnormal findings in the pancreatic duct without a mass may require serial pancreatic juice aspiration cytological examination. In cases of synchronous gastric cancer and stage 0 pancreatic cancer, spleen-preserving pancreatectomy may have advantage.

A safe and reliable technique for fascial closure without special devices after laparoscopic surgery.

INTRODUCTION: To prevent port-site hernia, we established a simple and low-cost closure method that uses a venous catheter needle and suture, without any other special devices. MATERIALS AND SURGICAL TECHNIQUE: We used the inner needle of a 16-G venous catheter and a 2-0 absorbable bladed suture. To evaluate the efficacy of this technique, the procedure time was noted and compared among three operators (an experienced surgeon and two inexperienced surgeons). DISCUSSION: The median suturing time was 60.5 seconds (range, 26-130 seconds) per incision. Even an unexperienced surgeon can close the fascia safely and quickly after some experience with the procedure.

A liver metastasis 7 years after resection of a low-risk duodenal gastrointestinal stromal tumor.

Duodenal gastrointestinal stromal tumors (dGISTs) are rare, and a lack of consensus exists regarding their treatment, particularly for recurrent disease. We herein report a rare case of liver metastasis 7 years after resection of a low-risk duodenal gastrointestinal stromal tumor. A 45-year-old woman revealed positive fecal occult blood. Upper gastrointestinal endoscopy revealed a submucosal duodenal tumor with ulceration and oozing on the apex. Endoscopic ultrasound showed a hypoechoic mass originating in the submucosa. Contrast-enhanced abdominal computed tomography (CT) revealed a 30-mm hyper-vascular tumor in the duodenal bulb. The patient underwent partial resection of the duodenal bulb with distal gastrectomy, followed by Roux-en-Y reconstruction. Histopathological evaluation revealed a tumor comprised of spindle-shaped cells including 5 mitotic figures per 50 high-power fields. Immunohistochemical evaluation indicated that the tumor cells were positive for c-Kit and CD34 expression. The tumor was diagnosed as low-risk dGIST. Postoperative follow-up was continued, and 7 years later, CT revealed a 39-mm enhanced tumor in liver segment 4. The tumor was diagnosed as a metastatic liver tumor, and the patient underwent S4 partial hepatectomy. As a result of histological and immunohistochemical analysis, the tumor was diagnosed as a liver metastasis from dGIST. The patient has been receiving oral imatinib 400 mg daily and remains free of disease 5 years after her last surgery. Low-risk dGIST can metastasize relatively long after surgery. However, an excellent long-term prognosis may be achieved by combining complete resection and imatinib therapy in patients with recurrent liver metastases.

Alpha-fetoprotein-producing Colon Carcinoma with Rapidly Increasing Liver Metastases That Resulted in Death: A Case Report.

Alpha-fetoprotein (AFP) has been widely used as a tumor marker for detecting hepatocellular carcinoma and yolk sac tumors. Recently, cases of gastrointestinal cancer with elevated serum AFP levels have been reported. However, AFP-producing colon cancer is considered rarer than other AFP-producing gastrointestinal cancers. In this study, we report on a case of a 47-year-old woman who was diagnosed with sigmoid colon cancer and underwent sigmoidectomy and lymph node dissection. Postoperative adjuvant chemotherapy (AC) was performed after the curative surgery. After the seventh course of AC, multiple liver masses and enlarged systemic lymph nodes were detected; these were later diagnosed as liver metastases from sigmoid colon cancer. Laboratory examination revealed high AFP levels (14,657.8 ng/mL). After confirming the recurrence, her condition worsened rapidly, and she eventually died 8 months after the operation. Autopsy and histopathological findings showed that the liver mass was positive for AFP staining, but the sigmoid colon cancer tissue was not. We then determined that liver metastases of the colon cancer were more likely than germ cell carcinoma according to the clinical course and pathological findings. We assumed that colon cancer cells can rapidly expand by dedifferentiation, and we diagnosed AFP-producing colon cancer with liver metastases. Despite curative surgery and AC for AFP-producing colon cancer, the patient died of liver and systemic lymph node metastases.

Mucinous nonneoplastic cyst of the pancreas penetrates the colon causing infection: a case report.

BACKGROUND: Mucinous nonneoplastic cyst of the pancreas is a rare disease defined as a cystic lesion lined with mucinous epithelium, supported by hypocellular stroma and not communicating with the pancreatic ducts. Mucinous nonneoplastic cyst of the pancreas has no malignant potential and does not require surgical resection or surveillance. However, its preoperative differentiation from other cystic lesions of the pancreas is difficult because of several overlapping clinical, radiological, and biochemical features. We report a rare case of large mucinous nonneoplastic cyst of the pancreas in which surgery was required due to infection and the possibility of malignancy. CASE PRESENTATION: A 75-year-old Japanese man was found to have a pancreatic cyst in 2006 while undergoing postoperative evaluation for colon cancer. In 2015, the cyst ruptured, and it was treated conservatively. In 2017, he fell down on a road with a fever of 40 °C and was transported emergently to a nearby hospital. Enhanced computed tomography revealed a cystic lesion in the body of the pancreas measuring 119 mm × 100 mm and an adjacent left renal cyst measuring 63 mm in diameter. The wall of the pancreatic cyst was thickened. Magnetic resonance imaging demonstrated a liquid surface in the pancreatic cyst. Pancreatic cyst infection was diagnosed as the source of infection. However, identification of the organism was difficult. Furthermore, due to the increase in the size and wall thickness of the cyst, it was unclear whether the cystic mass was neoplastic with malignant potential. For these reasons, the patient underwent distal pancreatectomy and splenectomy with deroofing of the left renal cyst. Intraoperatively, the pancreatic cyst adhered to the descending colon, and partial resection of the colon was added. Pathologic analysis of the resected cyst demonstrated a simple cyst lined by mucinous epithelium. There was no underlying stromal condensation or epithelial dysplasia, and communication with the native pancreatic ducts was not observed. Based on the operative and histological findings, a final diagnosis of mucinous nonneoplastic cyst of the pancreas with colonic communication was made. The colonic fistula was presumed to be the source of infection. CONCLUSION: Mucinous nonneoplastic cyst of the pancreas is generally benign and requires little follow-up, but large cysts may penetrate other organs and cause severe complications.

Prognostic Nutritional Index Predicts Treatment Outcomes following Palliative Surgery for Colorectal Adenocarcinoma.

OBJECTIVES: Palliative surgeries such as stoma creation and bypass are effective for relieving symptoms related to incurable abdominal malignancies; however, these methods are controversial in patients with severe metastatic disease or poor pre-surgical health. The aim of this study was to examine the clinical significance of the prognostic nutritional index (PNI) in evaluations for palliative surgery. METHODS: We retrospectively analyzed data from 37 patients who underwent palliative surgery for histologically-proven colorectal adenocarcinoma from 2009 to 2015. We investigated both risk factors for postoperative complications and prognostic factors. We used a PNI cutoff value of 40, as defined by previous studies. RESULTS: The reason for surgery was stenosis in 18 patients, obstruction in 12, fistula in 5, and bleeding in 2. Bypass was performed in 10 cases, ileostomy in 5, and colostomy in 22. Postoperative morbidity and mortality occurred in 9 and 2 patients, respectively. Median overall survival time was 8.9 months. Only low PNI correlated with postoperative complications at trend-level (p=0.07), and the 2 patients with mortality were classified as PNI-low. The presence of ascites (p=0.003) and PNI (p=0.02) were identified as independent prognostic factors. CONCLUSIONS: PNI could be used as an objective marker for deciding whether to proceed with palliative surgery, independent of the extent of metastatic disease.

Successful resection of liver metastasis detected by exacerbation of skin symptom in a patient with dermatomyositis accompanied by rectal cancer: a case report and literature review.

BACKGROUND: Dermatomyositis (DM) is a rare syndrome that belongs to the group of idiopathic inflammatory myopathies. The association between DM and malignancy is well recognized, and the severity of DM symptoms has been linked to the progression of metastatic disease. CASE PRESENTATION: We report the case of a 42-year-old man that was diagnosed with dermatomyositis (DM) and rectal cancer. Proctectomy was performed, and DM symptoms were resolved postoperatively. One year and 9 months after the surgery, liver metastasis occurred accompanied by the exacerbation of DM symptom. Partial resection of the liver was performed, and postoperative course was uneventful. DM symptoms improved postoperatively, and no evidence of cancer recurrence or DM symptoms was observed 2 years after the second surgery. To date, few reports have described recurring cases of DM accompanied by colorectal cancer in detail. We reviewed four similar cases that were reported poor prognoses with treatment resistance. However, our case report demonstrates good long-term results with resection of metastatic lesion. CONCLUSIONS: It is important to check the exacerbation of DM symptoms, as this symptom sometimes preceded cancer relapse during the follow-up of our patient with DM and colorectal cancer.

Hemorrhagic Cholecystitis in a Patient on Maintenance Dialysis.

The present paper describes a case of hemorrhagic cholecystitis in a patient on maintenance dialysis. The patient presented with right upper quadrant abdominal pain. Computed tomography revealed swelling of the gallbladder, high- and isodensity contents of the gallbladder, and high-density stone in the gallbladder neck. He was hospitalized for suspected acute cholecystitis. After hospitalization, his levels of total bilirubin, aspartate aminotransferase, and alanine aminotransferase increased. T2-weighted magnetic resonance imaging showed low-intensity contents expanded to include a wide area from the common bile duct to the cystic duct and gallbladder neck. Endoscopic retrograde cholangiopancreatography revealed clotting from the duodenal papilla. After cannulation of the bile duct, old blood and pus began to flow from the mammary papilla, and an endoscopic nasobiliary drainage tube was placed. After his liver function had improved, the patient underwent laparoscopic cholecystectomy. His sample revealed that the gallbladder was filled with blood clots and stones. His postoperative course was uneventful and he was discharged on day 19 after the procedure. Although hemorrhagic cholecystitis is rare, it should be considered as a differential diagnosis for patients on dialysis who have acute abdominal symptoms.