Two cases of functional and one case of non-functional parathyroid cysts are reported. Case 1 was a 45-year-old man who was referred to our department after a mass in the left cervical region was found on computed tomography. Blood Ca and parathyroid hormone (PTH) levels were both increased, and ultrasonography showed a 4.3-cm cystic mass on the inferior dorsal side of the left lobe of the thyroid. A functional parathyroid cyst was therefore diagnosed, and left inferior parathyroidectomy was performed. Case 2 was a 73-year-old woman who was referred to our department for treatment of a ureteral calculus. Blood Ca and PTH levels were both increased, and ultrasound showed a 3.4-cm cystic mass on the inferior caudal side of the right lobe of the thyroid. Brownish fluid was collected by centesis, and the high-sensitivity PTH level was also increased. A functional parathyroid cyst was therefore diagnosed, and right inferior parathyroidectomy was performed. Case 3 was a 29-year-old woman who had noticed a mass in the cervical region eight years earlier. Blood tests showed that Ca and intact PTH levels were both normal, and ultrasonography showed a 3.6-cm cyst touching the inferior-most point of the left lobe of the thyroid. Clear fluid was collected by centesis, and the high-sensitivity PTH level was increased. A non-functional parathyroid cyst was therefore diagnosed. After centesis, the swelling in the neck disappeared, and there has been no recurrent accumulation of fluid.

A 92-year-old man with a right proximal tibiofibular fracture underwent plate fusion via a lateral incision in the right calf in our hospital's Department of Orthopedic Surgery. In postoperative week 3, the wound site became dehiscent. A plastic surgeon carried out a skin graft to repair the skin defect after the use of a medial gastrocnemius flap and negative pressure wound therapy, but granulation was poor. Computed tomography (CT) contrast angiography showed multiple severe stenoses in the iliac artery region and the arteries of the legs, and arteriosclerosis of the lower extremities with multisegmental complex lesions was diagnosed. Our department judged that revascularization should be performed as rapidly as possible to save the leg, and a left external iliac artery-right popliteal artery bypass was performed. On day 6 after the bypass, the stenoses in the left external iliac artery and the common iliac artery were stented. The ankle-brachial index (ABI) improved, granulation tissue growth at the ulcerated site was good, and in postoperative week 3, the wound was closed with a skin graft. A case of complex lesions in an oldest-old patient with arteriosclerosis obliterans of the lower extremities, a disorder that is expected to become more common in the future, which was successfully treated with multimodal therapy consisting of hybrid revascularization and skin grafting by a plastic surgeon, is reported.

A 72-year-old man, who underwent right pneumonectomy for lung cancer 10 years earlier, was brought into our hospital by ambulance because of the abrupt onset of dyspnea. It was diagnosed as left pneumothorax. He was also diagnosed as having acute myocardial infarction and severe pulmonary emphysema. We decided to treat him conservatively. Chest drainage followed by six times of pleurodesis resulted in failure, and the massive air leakage persisted, therefore we performed surgical operation. While he was under general anesthesia, oxygenation was maintaind using extracorporeal membrane oxygenation (ECMO).

Bifemoral venovenous cannulas were used to perform extracorporeal circulation, and partial lung resection and suturing were performed for persistent air leakage. He was given instructions about the home oxygen therapy and was discharged home. For patients with pneumothorax with low respiratory function, surgery using ECMO is an option for surgery.

A 66-year-old woman diagnosed as having unclassifiable idiopathic interstitial pneumonia and receiving treatment as an outpatient was urgently hospitalized for left-sided tension pneumothorax. Since the bronchopulmonary fistula failed to close despite repeated attempts at pleurodesis with several chemical substances and endobronchial occlusions, surgical treatment was scheduled. To avoid a risk of developing pneumothorax on the contralateral side as well under positive pressure ventilation and the difficulty in keeping adequate ventilation, we decided to perform the surgery under extracorporeal membrane oxygenation (ECMO) support, after holding thorough discussions about its introduction and management with the staff of the concerned departments. At the time of the operation, veno-arterial ECMO was first established at the angiography laboratory. Then, the patient was wheeled to the operation room, where video-assisted bullectomy was performed with the patient placed in the right semi-lateral decubitus position. The ECMO could be withdrawn immediately after the operation. The chest drainage tube was removed on the third postoperative day. In patients receiving surgical treatment for intractable secondary pneumothorax, it is a challenge to manage the cardiopulmonary condition in the perioperative period. To perform the relatively uncommon operation smoothly and safely under ECMO support, we need thorough discussions beforehand with the staff of the concerned departments.

A 76-year-old man was diagnosed with cancer of the lower thoracic esophagus and underwent neoadjuvant chemotherapy with DCF regimen followed by thoraco-laparoscopic subtotal thoracic esophagectomy. As for esophageal reconstruction, we used a gastric tube anastomosed to the cervical esophagus via retrosternal route. He had neither postoperative recurrent laryngeal nerve paralysis nor a problem with swallowing, so that oral ingestion was initiated on the 7^th postoperative day. He vomited on the 9^th postoperative day when a chest X-ray film revealed dilatation of the gastric tube. Insertion of a nasogastric tube led to symptomatic remission, but the gastric tube dilatation recurred after removal of the nasogastric tube. Since no twisting of the gastric tube was revealed on CT, we diagnosed that the tube might have bent causing the dilatation. His symptom was resolved by temporary placement of a self-expandable metallic stent (SEMS) and he could resume oral ingestion. Thereafter anastomotic stenosis occurred between the cervical esophagus and the gastric tube. We performed endoscopic dilatation. After the anastomotic stenosis was relieved, the stent was removed on the 41^st day after the stent placement. After the stent removal, gastric tube dilatation has not recurred. He has been free from gastric tube dilatation and recurrence of esophageal cancer, as of 14 months after the operation.

A 76-year-old man visited our hospital with a complaint of hematemesis after meal. An abdominal CT scan showed free air around the lower intrathoracic esophagus and inferior mediastinum. And spontaneous esophageal rupture was diagnosed. Since free air was localized in the mediastinum and the disease was in an early stage after the onset, emergency laparoscopic esophageal suturing and mediastinal drainage were performed. Operation was started with 6 ports systems. No ascites was present. After an opening of the inferior mediastinum with an incision between the crura of the diaphragm and the abdominal esophagus, an about 2-cm perforated part was found in the lower intrathoracic esophagus. Subsequently to the lavage of the mediastinum with physiological saline, the perforated part was sutured with 3-0 absorbable sutures, where its periphery was trimmed beforehand. After the leak test, 19 Fr break drain tubes were placed under the left diaphragm and on the esophageal suture. He stared drinking on the 13th postoperative day, started a meal on the 18th postoperative day and was discharged on the 24th postoperative day. Since we experienced a case of spontaneous esophageal rupture in which a good postoperative course was obtained by early laparoscopic mediastinal drainage and esophageal suturing, we report the case with some literature considerations.

An 89-year-old man was found to have a 0-IIc lesion at the thoracic esophagus by an esophagogastroduodenoscopy in a medical checkup, and it was diagnosed as moderately differentiated squamous cell carcinoma by a biopsy. Considering his great age of 89, we performed curative radiation therapy (60 Gy) for squamous cell carcinoma (T1bN0M0 : Stage I) of the thoracic esophagus. Thereafter no recurrence had been detected by follow-up endoscopies until one year had elapsed after the completion of the irradiation, when abdominal pain occurred. He was diagnosed with intestinal obstruction caused by a tumorous lesion of the small intestine by CT and underwent emergency operation. The tumorous lesion was present in the ileum, a proximal small bowel to the lesion had dilated, and a nodular lesion was also identified in the ileum distal to the lesion. We thus performed enterectomy including the lesions. Histopathologically the both tumorous and nodular lesions were squamous cell carcinoma and appeared to be small bowel metastasis of esophageal squamous cell carcinoma.

This case was of superficial esophageal cancer successfully treated by curative irradiation, with subsequent small bowel metastasis causing intestinal obstruction. In performing radiation therapy particularly done without adjuvant chemotherapy, it is important to follow-up the patient by keeping a possibility of other organ metastasis as well as recurrence at the primary site in mind, even if he or she has superficial esophageal cancer.

We report a case of metachronous isolated splenic metastasis from gastric cancer in a 73-year-old man. The patient underwent total gastrectomy reconstructed with the Roux-en-Y method for a gastric cancer [U, Less, neuroendocrine carcinoma with adenocarcinoma, ypT3(SS), int, ly1, v2, pPM0, ypN1 ypStage IIB] with M, 0-IIa, tub1, ypt1a(M), ly0, v0, pDM0. Seven months later, abdominal ultrasonography showed a splenic tumor. Abdominal computed tomography (CT) and positron emission tomography (PET)/CT showed a hypodense mass in the spleen and focal ; an intense fluorine-18-fluorodeoxyglucose uptake with a standardized uptake value 16 (maximum) in the spleen was observed. The whole-body PET imaging showed no other lesions to suggest malignancy. Therefore, we conducted splenectomy under a diagnosis of solitary metastasis to the spleen from gastric cancer.

Histopathological examination showed moderately differentiated adenocarcinoma in the spleen, which was histologically compatible with the metastasis from gastric cancer. No evidence of recurrence has been found 27 months after surgery. We recommend splenectomy for metachronous isolated splenic metastasis from gastric cancer.

A 71-year-old man with the chief complaint of appetite loss had previously visited a doctor and had been diagnosed with esophagogastric junction cancer. Because of multiple fluid-filled blisters and erosions on the trunk and extremities, the patient was referred to our hospital for further detailed examination. Based on skin biopsy findings, he was diagnosed with bullous pemphigoid. Blood tests revealed advanced hypoproteinemia. From the clinical course, the onset of bullous pemphigoid was suspected to be a symptom of the malignant tumor. After steroid therapy and preoperative nutritional intervention, distal esophagectomy and proximal gastrectomy were performed. The pathological diagnosis was papillary adenocarcinoma, pStage IIIA. The postoperative course was uneventful. Recent examinations performed four months after surgery showed no evidence of recurrence. Furthermore, the skin symptoms and nutritional status improved after surgery. Bullous pemphigoid is an autoimmune bullous disease and has frequently been reported to be associated with malignant tumors ; however, their relationship was unclear. In this case, although the patient showed good response to steroid therapy, his skin symptoms further improved after tumor resection ; this suggested a strong association between bullous pemphigoid and maligmant tumor. In this study, we also discussed the clinical course and treatment strategy.

A 70-year-old woman who was on maintenance dialysis for diabetic chronic kidney disease and had previously undergone coronary artery bypass surgery for angina was found to have submucosal infiltration of the gastric antrum suggestive of early-stage carcinoma on upper gastrointestinal endoscopy. Abdominal computed tomography (CT) showed widespread calcification of vessels including the celiac artery, splenic artery, and short gastric artery. Distal gastrectomy and Billroth I reconstruction were performed laparoscopically. Widespread necrosis of the mucosa of the gastric remnant was visible on postoperative upper gastrointestinal endoscopy. On contrast-enhanced CT, the gastric wall was poorly contrasted, and several split were visible. Necrosis of the gastric remnant was diagnosed, and the gastric remnant was removed on postoperative day 13. After the second procedure, however, duodenal stump suture failure occurred, the patient's general condition deteriorated, and she died on day 23 after the initial surgery. The widespread calcification of the splenic and short gastric arteries in this patient may have reduced perfusion to the gastric remnant, which could have been one factor that contributed to its necrosis. Necrosis of the gastric remnant is an extremely rare complication of gastrectomy, but once it develops its course is frequently critical and its early diagnosis and early second surgery are vital.

A 72-year-old man experiencing movement-related pain was admitted to our hospital. Abdominal computed tomography images revealed a floating tumor sized 8 cm. The tumor was believed to originate from the stomach, and hence, a gastrointestinal stromal tumor (GIST) was suspected. A few days later, the patient experienced hematemesis. Upon physical examination, rupturing of the tumor was expected ; thereafter, an emergency surgery was planned. The tumor had a smooth surface and was located near the greater curvature of stomach. We planned a wedge resection of the stomach. However, endoscopic examination of the stomach during the surgery revealed hemorrhagic gastric cancer. Therefore, we performed an emergency D2 distal gastrectomy. Pathologic examination revealed that the giant tumor was a gastric cancer that metastasized to the lymph node. We diagnosed gastric cancer, pT2(MP)N1M0, stage II A. The patient's recovery was uneventful, and there has been no sign of recurrence 20 months after surgery. In this study, we reported our experience of gastric cancer with a solitary large lymph node metastasis along with a literature review.

A 70-year-old man was admitted to a hospital with sustained pain in the hypogastric region of his abdomen. He had a history of left nephroureterectomy for bladder cancer at 46 years of age and total cystectomy and ileal neobladder reconstruction for recurrence of the cancer at 54 years of age. Abdominal computed tomography revealed a sac-like dilatation of the functional end-to-end anastomotic site of the ileum, containing stagnant intestinal contents. The patient was diagnosed with blind loop syndrome, specifically categorized as the blind pouch type. Abdominal pain persisted, and an urgent operation was performed 3 days after admission, owing to the high risk of intestinal perforation. Although the dilated anastomotic region was not perforated, the anastomotic site was resected and reconstructed by layer-to-layer anastomosis. To date, no recurrence has been observed.

Blind loop syndrome of the functional end-to-end anastomotic site is rare. This condition should be considered a possible complication of functional end-to-end intestinal anastomosis, and surgical treatment is necessary in patients presenting with abdominal symptoms.

An 87-year-old woman underwent total colonoscopy following a positive fecal occult blood test. A type 2 tumor occupying two-thirds of the circumference was detected in the transverse colon close to the splenic flexure. The biopsy revealed a poorly differentiated adenocarcinoma. As computed tomography scans showed wall thickness and irregular serosa, the depth of the tumor was predicted to be T3 or deeper. The patient underwent an open partial transverse colectomy. The resected specimen showed only an ulcer at the tumor site. Histopathology revealed inflammatory cell infiltration and fibrosis at the ulcer site ; cancerous tissue was not found. A month and a half after surgery, total colonoscopy was performed ; this revealed an absence of tumor. There has been no evidence of recurrence for 4 years and 6 months. As CD8+ T cells aggregated around the tumor in the biopsy specimen, tumor immunity may have been associated with the spontaneous regression.

Portal vein thrombosis after laparoscopic colorectal cancer surgery is rare. To date, no reliable criteria are available regarding the optimal anticoagulant and its duration of administration in such cases. We report a case of portal vein thrombosis successfully treated with danaparoid sodium in a patient who underwent laparoscopic surgery for rectal cancer. A 59-year-old man underwent laparoscopic intersphincteric resection and ileostomy for lower rectal cancer (pT1a, N0, M0, pStage 0). Laboratory tests performed on the 29^th postoperative day revealed mild liver dysfunction. Abdominal ultrasonography and contrast-enhanced computed tomography revealed portal vein thrombosis in the umbilical portion. Complete resolution of the thrombus was observed following 2-week treatment with danaparoid sodium. We had treated the patient with warfarin for 8 weeks, and no recurrence of thrombus was observed. We concluded that thrombosis was attributable to a combination of reduced blood flow through the portal vein secondary to elevated intra-abdominal pressure, carbon dioxide pneumoperitoneum, and the Trendelenburg position used during laparoscopic surgery. Danaparoid sodium effectively treats portal vein thrombosis observed after laparoscopic surgery for colorectal cancer.

A 60-year-old woman with no particular complaints underwent abdominal contrast-enhanced computed tomography after blood tests showed elevated CEA levels, and she was found to have a 5-cm tumor in the left lower rectum. Further investigations led to a diagnosis of either gastrointestinal stromal tumor of the rectum or neurogenic tumor of the levator ani muscle, and laparoscopic tumorectomy was performed. The tumor was not continuous with either the rectum or the mesorectum, but it was continuous with the levator ani muscle, and part of this muscle was resected during tumor removal. Leiomyoma was diagnosed by immunostaining of the resected specimen. The magnifying effect of laparoscopy and sharing of the field of view made the discontinuity between the tumor in the deep pelvis and the lower rectum easy to confirm, and laparoscopic surgery was useful in this case. An extremely rare case of leiomyoma occurring in the pararectal space (the space above the levator muscle) is reported.

A 70-year-old woman visited to a local clinic with right abdominal pain. A mass was identified in the liver, and she was referred to our department. She underwent right hepatic lobectomy and cholecystectomy for what was believed to be atypical primary hepatocellular carcinoma. The postoperative pathological diagnosis was neuroendocrine carcinoma (NEC) according to the 2010 World Health Organization (WHO) classification. Preoperative upper and lower gastrointestinal endoscopy, computed tomography (CT), and magnetic resonance imaging, and postoperative positron emission tomography CT did not show any lesion that might be a primary lesion at any other site, and this was therefore considered a case of primary hepatic NEC (PHNEC). However, the WHO classification was revised in 2017, and according to this version, this case would be diagnosed as a Grade 3 neuroendocrine tumor (NET). Primary hepatic NET is rare, and much about its diagnosis and treatment strategy remains unknown.

A 62-year-old woman was admitted for epigastric pain and jaundice. Abdominal enhanced computed tomography (CT) showed a high-density tumor in the lower bile duct and a dilated common bile duct. After biopsy, we suspected adenocarcinoma in the lower bile duct and performed pancreatoduodenectomy. Tumor cells with a high nuclear-cytoplasmic (N/C) ratio and nested pattern were confirmed by histological examination. Immunostaining findings were positive for chromogranin A and synaptophysin. The Ki-67 index was > 90%. Consequently, we diagnosed large cell neuroendocrine carcinoma (LCNEC) in the lower bile duct. As adjuvant chemotherapy, cisplatin and irinotecan were administered. However, three months after surgery, a recurrence was observed in the lymph nodes. Ten months after surgery, the patient died due to recurrence in the lymph nodes, multiple liver metastases, and peritoneal dissemination. LCNEC in the bile duct is extremely rare and appears to be highly aggressive with early recurrence and metastases.

A 71-year-old woman was referred to our hospital with generalized fatigue after being diagnosed with jaundice and liver dysfunction at another hospital. Abdominal contrast-enhanced computed tomography revealed a groove pancreatic tumor measuring 30 mm in size and an aberrant right hepatic artery, which originated from the gastroduodenal artery and penetrated the tumor. Angiography revealed a stricture of the right hepatic artery and an enlarged communicating artery between the left and right hepatic arteries. Therefore, we performed preoperative embolization of the right hepatic artery. Six days later, subtotal stomach-preserving pancreatoduodenectomy was successfully performed with resection of the right hepatic artery. Surgical treatment of pancreatic head cancer should necessarily include the following steps : (a) preoperative imaging to accurately identify the aberrant hepatic artery and, (b) selection of the optimal approach based on the type of aberrant hepatic artery identified. We successfully performed safe and curative subtotal stomach-preserving pancreatoduodenectomy following preoperative embolization of the aberrant hepatic artery.

The case involved a 54-year-old woman who underwent abdominal simple total hysterectomy for carcinoma of the uterine cervix (Stage IB) and postoperative radiation therapy 21 years earlier. She was referred to our surgical department for close exploration and treatment of an enlarging tumor in the left lateral abdomen. An abdominal MRI scan revealed an 11-cm cystic tumor on the lateral aspect of the left kidney. When she was first seen at our clinic, she described that her ovaries had been preserved and transposed at the previous operation for uterine malignancy. We thus consulted an oncologic gynecologist about it. Then we recognized a possibility that, in the post-hysterectomy irradiation, a surgical maneuver they selected was to transpose and fix the ovaries outside of the radiation field so as to avoid radiation exposure and to preserve the ovarian function. A left ovarian cyst after ovarian transposition was suspected, and laparoscopic removal of the tumor was performed. The histopathological diagnosis was ovarian mucinous cystic adenoma (benign). Her postoperative course was uneventful and she was discharged home on the 7th postoperative day.

Synovial sarcoma is a rare potentially malignant tumor that accounts for 7% of all soft tissue tumors. It often develops in individuals aged late teens to thirties. Synovial sarcoma usually arises in the vicinity of the joints ; those occurring in the abdominal wall accounts for only 2.6% of all synovial sarcomas. We describe a rare case with a relevant discussion on synovial sarcoma.

A-39-year-old man was admitted to our hospital with a complaint of left hypochondriac pain. Through palpation, we identified a smooth and fixed tender mass, sized 3 cm, situated in the left hypochondrium. Abdominal CT scan revealed a well-defined tumor sized 58×52 mm projecting into the peritoneum from the abdominal wall. The tumor showed predominantly low-intensity signals mixed with high-intensity signals ; therefore, it was difficult to diagnose based on these images. As the patient experienced pain and we found no apparent invasion of the abdominal organs, we resected the tumor. Upon histopathological examination the tumor was diagnosed to be a synovial sarcoma. After surgery, the patient received chemotherapy followed by radiation therapy to reduce the risk of recurrence. Since three years post-surgery, there has been no recurrence.

A 68-year-old man received endoscopic treatment of gastric cancer, of which pathology found vascular invasion positive. Abdominal CT scan showed a tumor with clear boundary and heterogeneous inner part.

The tumor, 38×14mm in diameter, was located between the abdominal aorta and the inferior vena cava. The possible diagnosis was a retroperitoneal tumor such as para-aortic lymphadenopathy or schwannoma. Gastrectomy and simultaneous removal of the tumor were scheduled. When we were going to remove the tumor, his blood pressure elevated extremely, so the surgery was discontinued. The urine examination revealed increased amounts of catecholamines, an abdominal MRI showed the high intensity tumor on T2-weighted image, and a MIBG scintigraphy showed the uptake of MIBG to the tumor. Paraganglioma was thus diagnosed. The re-operation was carried out two weeks later. When we started to remove the tumor, his blood pressure fluctuated slightly, but became stable after its blood vessel dissection. The tumor removal followed by curative operation for gastric cancer was performed without problems. The pathological diagnosis was paraganglioma. Paraganglioma is a rare tumor.

Even if blood pressure is normal and the patient is asymptomatic, it is necessary to keep a paraganglioma in mind when a para-aortic tumor is detected.