Pembrolizumab is an immunoglobulin G4 isotype antibody that targets the programmed cell death protein 1 (PD-1) receptor of lymphocytes. It is used in the treatment of advanced non-small cell lung cancer (NSCLC). The safety and efficacy of immunotherapy for autoimmune disease are currently unknown;immune-related adverse events induced by immune checkpoint inhibitors (ICIs) have been reported. We report a case of severe colitis induced by the administration of pembrolizumab for pulmonary adenocarcinoma in a patient with ulcerative colitis. A 72-year-old man with a 3-year history of ulcerative colitis maintained clinical remission with mesalazine. The recurrence of lung adenocarcinoma was diagnosed and treated with pembrolizumab as second-line treatment. Diarrhea and bloody stool recurred 5 months after the first administration of pembrolizumab. The colitis did not respond to corticosteroids and infliximab. Because of the recurrence of ulcerative colitis, treatment of the lung adenocarcinoma was discontinued, and the patient died 1 year after the first administration of pembrolizumab. Few cases of severe colitis induced by the administration of pembrolizumab in patients with ulcerative colitis have been reported. This case suggests that the clinical stratification of autoimmune disease and typical standards of effectiveness of treatment are needed for patients with autoimmune disease who are treated with ICIs.

Primary synovial sarcoma of the spermatic cord is quite rare and has not been reported in Japanese literature. We report a case of primary synovial sarcoma of the spermatic cord and localized dissemination of the tumor in a patient who experienced recurrence of intra-abdominal bleeding 7 years after curative resection of the primary lesion. A 70-year-old man was admitted with disturbance on urination and lower abdominal pain. Computed tomography (CT) of the abdomen revealed two lesions:a 10-cm intrapelvic tumor with hemorrhage and a 4-cm tumor adjacent to the bladder. Curative excision of the tumors was performed. Histological examination revealed that the larger lesion was a primary tumor of the spermatic cord with proliferation of spindle cells in cellular fascicles in a monotonous pattern, which was compatible with histologic findings of monophasic fibrous synovial sarcoma. The smaller lesion was a disseminated tumor. The diagnosis of synovial sarcoma was confirmed by the detection of a SS18 (SYT) -SSX1 fusion gene. After discharge, the patient received adjuvant chemotherapy, including ifosfamide and doxorubicin. No recurrence was evident thereafter. Seven years after the operation, the patient experienced sudden abdominal pain and swelling and was transferred to our hospital. CT showed a 17-cm tumor with massive hemorrhage in the omental bursa. Through catheterization of the superior mesenteric artery, bleeding from a branch of the dorsal pancreatic artery was identified. Because of the difficulty of catheterizing the bleeding branch, he underwent emergency resection of the tumor and partial resection of the colon. Histologic examination and genetic testing revealed that the tumor was a recurrence of the synovial sarcoma. After discharge, the patient received treatment with gemcitabine and docetaxel. However, 7 months after the second surgery, intraperitoneal manifestations recurred. The patient died 14 months after the second resection. This case suggests that curative surgical resection of the primary synovial sarcoma of the spermatic cord contributes to prolonged survival. However, because the recurrence rate of synovial sarcoma is high, multidisciplinary treatment, including chemotherapy and radiotherapy, might be necessary.

A 38-year-old woman was referred to our department to investigate epigastric discomfort. Laboratory studies showed increases in the peripheral white blood cell count and the level of C-reactive protein. Abdominal computed tomography depicted inflammation and a mass in the horizontal part of the duodenum. To observe it directly, we performed esophagogastroduodenoscopy (EGD), but it was very difficult to reach the lesion. Therefore, we performed enteroscopy by using SIF-H290S (Olympus Europa SE & Co. KG, Hamburg, Germany), which revealed a diverticulum containing food residue in the horizontal part of the duodenum. Using grasping forceps, we removed the food residue. The patient recovered over the next several days. Endoscopic therapy was thus effective for duodenal diverticulitis caused by food residue, but attention to technique was necessary.

A Japanese woman in her 40s came to our emergency room with vomiting and upper abdominal pain after drinking a bottle of milk tea at home. She had a history of bipolar disorder. Blood tests revealed hypercalcemia (calcium level of 18.6mg/dl). Abdominal computed tomography depicted thickening of the gastric wall and hyperabsorbed material in the stomach. Upper gastroduodenal endoscopy showed extreme mucosal redness from the gastric body to the pylorus. The hypercalcemia improved with intravenous infusion of zoledronic acid. The patient had not been taking any medication that could have caused hypercalcemia. Later, her father drank the same bottle of milk tea at home and developed upper abdominal pain. He was admitted to the hospital because of vomiting, and computed tomography showed hyperabsorbed material in the stomach, as in his daughter's case. Computed tomography of the bottle of milk tea revealed a highly absorbent substance. The bottle was sent to the forensics laboratory for testing, and it was found to contain calcium chloride. Thus both patients had consumed a beverage containing calcium chloride, and corrosive gastritis was diagnosed. Despite fasting and intravenous drip therapy, the first patient underwent a total gastrectomy because of severe stenosis and perforation of the gastric lumen.

We describe two cases of type 2 autoimmune pancreatitis (AIP). A 39-year-old man presented to our hospital with complaints of epigastric and back pain. Pancreatic enzyme levels were elevated, but serum levels of immunoglobulins G and G4 (IgG and IgG4) were normal. Computed tomography (CT) showed diffuse pancreatic enlargement, and endoscopic retrograde pancreatography revealed diffuse narrowing of the pancreatic duct. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) revealed granulocytic epithelial lesions and very few IgG4-positive cells. Colonoscopy revealed ulcerative colitis. Type 2 AIP was diagnosed, and 5-aminosalicylic acid (5-ASA) and prednisolone were administered. The clinical course has since been favorable, and the prednisolone dose is currently being reduced. A 47-year-old woman presented to our hospital with complaints of bloody stools. Colonoscopy revealed ulcerative colitis. CT depicted diffuse pancreatic enlargement with a capsule-like rim. Pancreatic enzyme levels were elevated, but serum levels of IgG and IgG4 were normal. On magnetic resonance cholangiopancreatography, the pancreatic duct could not be delineated. No pathological findings of type 2 AIP were obtained on EUS-FNA. Type 2 AIP was suspected, and 5-ASA and steroid enemas were administered. To date, recurrence has not been observed, and 5-ASA management continues. The two cases differed with regard to sex of patient, clinical course, pathological findings, and treatment.

A 67-year-old man with a history of esophageal and gastric varices that were treated endoscopically was treated for Budd-Chiari syndrome and immunoglobulin G4-related sclerosing cholangitis in our facility. Varices in the second portion of the duodenum were revealed in follow-up upper endoscopy. The draining vein formed a venous plexus that was detected on computed tomography. Treatment with interventional radiology was difficult;therefore, endoscopic injection sclerotherapy (EIS) was performed instead. No recurrence has been observed to date. Thus, in this case, EIS for duodenal varices was effective.