[A Case of High-Grade Appendiceal Mucinous Neoplasm].

A 70-year-old woman underwent conservative treatment for abscess-forming appendicitis. A contrast-enhanced abdominal computed tomography(CT)revealed a cystic lesion at the appendiceal base while the abscess had disappeared posttreatment. With the diagnosis of a low-grade appendiceal mucinous neoplasm(LAMN), a laparoscopic-assisted ileocolic resection was performed. The appendix was distended with mucus in the lumen. Histopathological examination showed that the tumor cells were more atypical than that of low-grade appendiceal mucinous neoplasm. There were no findings of adenocarcinoma, such as invasive growth. Therefore, high-grade appendiceal mucinous neoplasm(HAMN)was diagnosed. HAMN is a term advocated by Carr et al in 2016 to classify appendiceal mucinous neoplasm and was noted as a new category of mucinous tumors among appendiceal epithelial tumors in the fifth edition of the 2019 revised WHO classification. HAMN is a rare disease and only one case has been reported in Japan. It has not yet been noted in the Japanese Colorectal Cancer Treatment Manual. Here, we report this rare case with a review of the study.

Duplicate appendix complicated by low-grade appendiceal mucinous neoplasm: a rare case report and review of the literature.

Low-grade appendiceal mucinous neoplasms (LAMNs) have been a very controversial tumor, and there is a lack of standardization for the optimal surgical procedure due to the infrequency of this disease. This is the first case report of duplicate appendix complicated by LAMN. The preoperative imaging examinations revealed that the mucinous tumor was shrinking spontaneously, allowing for safe laparoscopic resection. The histopathological findings indicated a dilated common base of the duplicated appendix, suggesting that the mucinous content drained spontaneously to the cecum. Further studies of the various complications of LAMNs are needed to establish the optimal surgical approach for LAMNs.

[Clinical Experience with 13 Cases of Primary Small Bowel Adenocarcinoma].

Between 2003 and 2017, 13 patients with primary small bowel adenocarcinoma(SBA)were treated at our hospital. Tumors developed in the duodenum in 6 patients and in the jejunum in 7 patients. The median age of the patients was 62 (range: 31-83)years and male/female ratio was 10/3. Initial symptoms were obstruction in 5 patients, bleeding in 3 patients, and abdominal pain in 1 patient. The median diameter of tumor was 50(range: 23-100)mm. Concerning surgical margin, R0 resection was in 8 patients, R1 resection in 3 patients, and R2 resection in 2 patients. The number of patients with stage 0 disease was 1, stage Ⅱ was 2, stage Ⅲ was 6, and stage Ⅳ was 4. Chemotherapy was provided to 8 patients. The median survival time was 31.6(range: 1-118)months and 5-year survival rate were 26.9%. Four patients survived longer than 4 years without recurrence. Although there is no treatment established for SBA, it was thought that proactive resection and chemotherapy can be anticipated in these patients to bring about an improved survival.

[A Case of Adenocarcinoma Arising from Ectopic Gastric Mucosa in Meckel's Diverticulum with Abdominal Wall Abscess].

A 47-year-old woman visited a neighboring hospital because of lower abdominal pain and high fever. She was diagnosed with acute pyelonephritis and administered(oral)antibiotics. However, there was no sign of improvement. She was referred to our hospital for closer examination. Computed tomography revealed an 8 cm abdominal wall abscess spreading from the prevesical space to the rectus abdominis. Incisional drainage was performed under local anesthesia. She developed rectus abdominis muscle diastasis, and a laparotomy was performed 2 months later. Intraoperative findings showed that her Meckel's diverticulum was continuous with the abdominal wall abscess. Diagnosed with Meckel's diverticulitis with abdominal wall abscess, the patient underwent surgery(excision)for these. Histopathological findings showed adenocarcinoma cells in the abscess tissue and were continuous with gastric pyloric gland-like tissue in Meckel's diverticulum. Based on these findings, the patient was diagnosed with adenocarcinoma arising from ectopic gastric mucosa in the Meckel's diverticulum. The patient received postoperative adjuvant chemotherapy for a year. The patient is currently alive and has not experienced recurrence for 2 years since surgery. It is difficult to diagnose carcinoma of Meckel's diverticulum preoperatively due to late onset of symptoms. The diagnosis is often made at the advanced stage, when the prognosis is poor. This case is rare due to the incidental finding of an abdominal abscess and the absence of recurrence 2 years after surgery.

[A case of metastatic liver tumor from gastric carcinoma curatively undergoing left hemihepatectomy and caudate lobectomy with ivc reconstruction].

A 72-year-old male underwent distal gastrectomy with D2 dissection for type 2 advanced gastric carcinoma. Nine months after the surgery, CT scan revealed a solitary liver metastatic legion with IVC invasion. We selected a surgical intervention because of allegic reaction of S-1 and rapid progression of tumor. Left hemihepatectomy and caudate lobectomy with IVC reconstruction was performed. IVC was resected partially and repaired with polytetrafluoroethylene (PTFE) patch graft. The postoperative course was uneventful. The patient was discharged on the 11th postoperative day. He is alive without a recurrence 9 months after surgery and is undergoing weekly paclitaxel. Although the indication of extended hepatectomy is controversial, aggressive surgery with chemotherapy would contribute to improve a prognosis of the patients with metastatic liver tumor from gastric carcinoma.

[Histological complete response in a case of primary squamous cell carcinoma of the stomach treated by chemotherapy with docetaxel and cisplatin plus 5-fluorouracil].

The patient was a 68-year-old man with melena. Endoscopic examination revealed a type 2 advanced tumor in the mid body and an elevated lesion in the upper body of the stomach. Biopsy specimens from both lesions were diagnosed histologically as squamous cell carcinoma. Abdominal CT showed thickening of the midbody in the greater curvature and bulky lymph nodes along the lesser curvature (No. 3), and the greater curvature(No. 4d). We diagnosed Stage IIIB (cP0, cH0, cT4, cN1, cM0) cancer, but we concluded radical resection would be difficult due to lymph node invasion to the diaphragm and mesocolon. DCF combination therapy (docetaxel 75 mg/m2 day 1, CDDP 75 mg/m2 day 1, 5-FU 750 mg/m2 day 1-5) was administered. After 3 courses of chemotherapy, endoscopic examination and abdominal CT findings showed remarkable reduction of the primary tumor and the lymph node metastasis, indicating a partial response (PR) to the chemotherapy. After consultation with the patient, total gastrectomy with lymph node dissection (D2) was performed. The pathological specimens showed no cancer cells in the gastric wall and lymph nodes, so the histological effect was judged as Grade 3. This case suggested that DCF combination chemotherapy may prove useful to treat patients with advanced squamous cell carcinoma of the stomach.

[A case of liver metastatic recurrence of bile duct cancer completely responding to single-drug S-1 chemotherapy].

A 65-year-old man with common bile duct cancer was treated by pylorus-preserving pancreaticoduodenectomy with D2 lymph node dissection. Three months after surgery, tumor marker was increasing, and CT demonstrated multiple liver metastatic tumors. Single drug chemotherapy with S-1(100 mg/body/day)was administered. After 6 months, the liver metastatic tumors could not be visualized by CT. S-1 may be the chemotherapy of choice for recurrence of bile duct cancer.