[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.

A Novel Parameter Identified Using Indocyanine Green Fluorescence Angiography may Contribute to Predicting Anastomotic Leakage in Gastric Cancer Surgery.

BACKGROUND: Anastomotic leak is one of the most serious postoperative complications, and intraoperative adequate perfusion plays a key role in preventing its development in gastric cancer surgery. This study aimed to investigate the relationships between anastomotic leak and the parameters defined by an assessment of intraoperative anastomotic perfusion using a near-infrared indocyanine green (ICG) fluorescence system and to evaluate the usefulness of this ICG fluorescence assessment in gastric cancer surgery. METHODS: We retrospectively reviewed data of 100 patients who underwent gastric cancer surgery. In a visual assessment based on fluorescence intensity, we classified ICG fluorescence image patterns as homogeneous, heterogeneous, or faint. In a chronological assessment, the first or second time point of ICG fluorescence appearance on one or the other side of the anastomosis was defined as FT or ST, respectively. The time difference in ICG fluorescence appearance between FT and ST was defined as TD. The relationships between anastomotic leak and the evaluated clinical factors, including the parameters identified by the ICG fluorescence assessment, were evaluated using univariate or multivariate analysis. RESULTS: Although no signs of leak were found by surgeons' subjective judgments, four patients developed postoperative anastomotic leak of Clavien-Dindo grade III or IV. Multivariate analysis revealed that TD was an independent predictor of anastomotic leak (odds ratio 35.361, 95% confidence interval 1.489-839.923, p = 0.027). CONCLUSIONS: A novel parameter identified using near-infrared ICG fluorescence assessment may be useful to predict anastomotic leak in gastric cancer surgery. TRIAL REGISTRATION: UMIN Clinical Trials Registry: #UMIN000030747 ( https://www.umin.ac.jp/ctr/index.htm ).

[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.

[Transverse Colectomy with D2 Lymph Node Dissection with a Small Incision Using Body Surface 3D-Simulation CT Colonography].

BACKGROUND: Laparoscopic transverse colectomy is technically difficult. In mini-laparotomy surgery, colectomy for midtransverse colon cancer can easily be performed, but exact D2 lymph node dissection is very difficult for a variety of vessels in the transverse colon. Using 3D-CT imaging, we present a case of D2 lymph node dissection where mini-laparotomy transverse colectomy was performedby a small incision similar to that usedin laparoscopic surgery. METHOD: The patient was a 60-yearoldwoman with early transverse colon cancer, which was locatedin the mid-transverse colon. Surgical treatment was plannedfor pT1b(1.5mm)andpVM1 in pathological findings after EMR. Using CT colonography(CTC), the location of the primary tumor was identified. Using simulation CTC(sCTC), composedof CTC and 3D imaging of the arteries andveins, the dominant artery was identified and D2 lymph node dissection was simulated. In addition, body surface 3D imaging and permeable surface 3D imaging of the abdominal trunk were performed. Using body surface 3D-sCTC, composedof sCTC and body surface 3D imaging, the minimum incision to enable D2 lymph node dissection was simulated. RESULT: Using sCTC, it was identified that the dominant artery was the right branch of the middle colic artery(MCA Rt)andthe accompanying vein was branchedfrom the gastrocolic trunk(GCT). D2 lymph node dissection to separate the branching root of MCA Rt and the accompanying vein was simulated. Next, surgical incision was simulated using body surface 3D-sCTC. Because the branching roots of MCA Rt andGCT were locatedabout 5 cm cranial from the upper rim of the navel, a 7 cm upper abdominal midline incision was designed in addition to a 2 cm umbilical incision. Mini-laparotomy transverse colectomy with a 7 cm incision was performedin accordance with the simulation. The operation time was 2 hours and5 1 minutes, andbloodloss was due to occult bleeding. The patient was discharged 7 days after surgery without complications, and the final diagnosis was pT1bN0M0, StageⅠwith no recurrence for 4 years and2 months after surgery. The cranial incision from the upper rim of the navel has shrank about 3 cm, and the umbilical incision is not noticeable. CONCLUSION: D2 lymph node dissection of minilaparotomy transverse colectomy can be a treatment option for early transverse colon cancer through using body surface 3DsCTC.

[Hepatic inferior vena cava resection and vascular prosthesis reconstruction for locally advanced intrahepatic cholangiocarcinoma - a case report].

A 61-year-old woman was referred to our hospital because of jaundice and general itching. Computed tomography (CT) scan demonstrated that the tumor was located in the caudate lobe of the liver with hilar invasion and involved the hepatic inferior vena cava (IVC) and the right renal artery and vein. The patient was diagnosed with locally advanced intrahepatic cholangiocarcinoma, for which she underwent right hemihepatectomy with right caudate lobectomy, portal vein resection, hepatic IVC resection, extrahepatic bile duct resection, and right nephrectomy. IVC was reconstructed using vascular prosthesis by expanded polytetrafluoroethylene (ePTFE)-ringed graft. The patient's postoperative course was uneventful. The patient was treated with gemcitabine for postoperative chemotherapy, and 3 years after the operation, she died due to recurrence resulting from peritoneal dissemination. Although the thrombosis-related vascular prosthesis obstruction had occurred 2 years after the operation, no clinical symptom were noted, such as lower leg edema or renal dysfunction, during the postoperative course. Hepatic IVC prosthesis reconstruction for locally advanced cancer with extensive IVC invasion can be a useful surgical procedure for improving the resection rate and maintaining quality of life (QOL) in such cases.

[A case of locally advanced gastric cancer in which pathological complete response( PCR) was obtained after combination chemotherapy with S-1/cisplatin].

A 72-year-old man with advanced gastric cancer was referred to our hospital. Upper gastrointestinal endoscopy revealed a type 3 tumor in the gastric antrum and pyloric stenosis. Computed tomography( CT) demonstrated that the tumor had directly infiltrated the pancreatic parenchyma and that the paraaortic lymph nodes were enlarged. We judged the tumor to be unresectable and performed gastrojejunostomy. Postoperatively, the patient was treated with 9 courses of combination chemotherapy comprising S-1 and cisplatin( CDDP), and significant tumor reduction was obtained. Therefore, we performed radical distal gastrectomy with D2 lymphadenectomy. Histological examination revealed a complete absence of cancer cells in the stomach and all of the lymph nodes( pathological complete response: pCR). Seven months after surgery, the patient is in good health with no recurrence. This case suggests that aggressive chemotherapy can be a useful treatment to enable radical surgery for unresectable locally advanced gastric cancer.