616 Rare KIT gene mutation in a recurrent GIST: Case Report

Introduction The diagnosis and treatment of Gastro-intestinal stromal tumours (GISTs) has been revolutionized by molecular pathology and targeted therapy. Description This patient was diagnosed with locally advanced gastric GIST in 2009. He was initially treated neoadjuvantly with imatinib from 2009- 2010. He underwent laparoscopic resection in 2010. Pathology showed almost complete response with only 1.5mm focus of viable tumour. He did not receive adjuvant imatinib as this was not established practice in 2010. Recurrent disease was resected in 2011. Mitotic count was 200/50hpf. Adjuvant imatinib was given for 5 years then discontinued in 2016. Imaging showed no recurrence over this time period. Molecular testing showed Kit Exon 11 mutation- this is common in GISTs and associated with response to imatinib. Recurrent disease was diagnosed 2018 with a 10x9cm mass between residual stomach and liver– he recommenced imatinib with partial response (maximal response was reached in 2020, but a new 3cm lesion was noted) He underwent further resection of the residual stomach and liver segmentectomy in 2020. Histology showed acellular areas of myxoid degeneration, indicating treatment response however viable tumour remained. Sequencing was performed. This showed the expected mutation in exon 11 but also a mutation in exon 13 of KIT- this has been shown recently to confer resistance to imatinib. Discussion Over 90% of GISTs harbour mutations in c-KIT. Recent work has demonstrated that some tumours acquire secondary mutations conferring resistance, following prolonged TKI therapy. Radiological and histopathological features correlate with such events and assist in deciding surgical management.

Analysis of risk factors and prevention strategies for functional delayed gastric emptying in 1243 patients with distal gastric cancer

Background Analysis of the risk factors associated with functional delayed gastric emptying after distal gastric cancer surgery to provide a basis for further reduction of the incidence of this complication. Methods Total of 1382 patients with distal gastric cancer from January 2016 to October 2018 were enrolled. Correlation analysis was performed in 53 patients with FDGE by logistic regression. Subgroup risk analysis was performed in 114 patients with preoperative pyloric obstruction. A Pearson Chi-square analysis was used to compare categorical variables between normal distribution groups. Meanwhile, a t test was used to compare continuous variables between groups. Odds ratio (OR) was used for comparison of the two groups, and it was summarized with its 95% confidence interval (CI) and p value using logistic regression. Result In multivariable analysis, age (OR 1.081, 95% CI, 1.047–1.117), BMI (OR 1.233, 95% CI, 1.116–1.363), preoperative pyloric obstruction (OR 3.831, 95% CI, 1.829–8.023), smaller volume of residual stomach (OR 1.838, 95% CI, 1.325–6.080), and anastomosis in greater curvature perpendicular (OR 3.385, 95% CI, 1.632–7.019) and in greater curvature parallel (OR 2.375, 95% CI, 0.963–5.861) were independent risk factors of FDGE. In the preoperative pyloric obstruction group, higher BMI (OR 1.309, 95% CI, 1.086–1.579) and preoperative obstruction time (OR 1.054, 95% CI, 1.003–1.108) were independent risk factors of FDGE and preoperative gastrointestinal decompression (OR 0.231, 95% CI, 0.068–0.785) was independent protective factor of FDGE. Conclusion Adequate gastrointestinal decompression should be performed before the operation to reduce the incidence of postoperative gastroparesis in patients with preoperative pyloric obstruction. We also could improve the surgical methods to reduce the occurrence of FDGE, such as controlling the size of the residual stomach, ensuring blood supply. Especially selecting an appropriate stapler and anastomosis during the anastomosis process, the occurrence of FDGE can be reduced.

Сase of successful treatment of chronic gastric remnant haemorrhagic ulcer after Roux-en-Y gastric bypass

Acute bleeding from a gastric remnant ulcer is an exceptionally rare complication, especially if it occurs several years after bariatric surgery. We present a case of a patient with a bleeding gastric remnant ulcer that occurred 6 years (20132019) after the Roux-en-Y Gastric Bypass (RYGB) performed for morbid obesity. The patient was urgently hospitalized in the surgical department with the clinic of gastrointestinal bleeding, according to fibroesophagogastroscopy, no sources of bleeding were found in the examined departments. On the background of conservative treatment, there was an improvement in the condition, but on the fifth day of hospitalization there was a clinic of recurrence of bleeding, while repeated emergency endoscopic examination of the sources also did not reveal. In this regard, it was decided to perform surgery to examine the residual stomach. With the help of laparoscopic transgastric gastroduodenoscopy, we were able to detect the source of active bleeding in the stomach excluded from digestion - a bleeding ulcer in the area of small curvature. The removal of this stomach was performed with a good postoperative recovery: the patient was discharged in a satisfactory condition for outpatient treatment, currently feels well, returned to work.

Acinar Cell Cystadenocarcinoma of the Pancreas

Acinar cell cystadenocarcinoma is a rare malignant epithelial neoplasm of the pancreas with a diffusely cystic, gross architecture in which the cysts are lined with neoplastic epithelial cells that demonstrate evidence of pancreatic exocrine enzyme production. This is the 10th case that has been reported in the literature. A 77-year-old male complaining of left hypochondrial pain was referred to our hospital for treatment of a pancreatic tumor. A huge, honeycomb-structured tumor was detected in the pancreatic tail. Distal pancreatectomy with total resection of the residual stomach and partial resection of the transverse colon were performed. Microscopically, there were variably sized cystic lesions in the tumor. Immunohistochemical examinations revealed that tumor cells were positive for alpha 1-antichymotrypsin and alpha 1-trypsin, showing that tumor cells had features of pancreatic acinar cells. Thus, the tumor was diagnosed as acinar cell cystadenocarcinoma. Herein, we report a rare case with acinar cell cystadenocarcinoma, which is the 10th case reported in the literature based on a PubMed search. We managed to resect the tumor completely by distal pancreatectomy with total resection of the residual stomach and partial resection of the transverse colon. The patient is still alive 26 months after surgery without any recurrence after 1 year of adjuvant chemotherapy with S-1.

Significance of Splenectomy for Upper Gastric Carcinoma With Invasion to the Greater Curvature

This study aimed to clarify the significance of splenectomy (Sp) for upper gastric carcinoma with invasion to the greater curvature. The Japan Clinical Oncology Group (JCOG) conducted a phase III randomized clinical trial (JCOG 0110), where the significance of Sp in total gastrectomy (TG) for upper gastric carcinoma without invasion to the greater curvature was not proved because Sp did not contribute to an improved prognosis. From 1992 to 2010, 167 patients underwent TG for carcinoma of the upper stomach, except for patients with carcinoma of the residual stomach. Among them, 60 patients with tumor invasion to the greater curvature of the upper stomach (Gre group) were enrolled. Within the Gre group, the following factors were compared between the Sp group (n = 30) and non-Sp group (n = 30): patient background, postoperative staging, rate of neoadjuvant chemotherapy, surgical outcomes and rates of R0 resection, morbidity, adjuvant chemotherapy, and overall survival (OS). The Gre group patients were relatively younger, and tumor size and the numbers of Borrmann type 4 tumors, circumferential lesions, undifferentiated type lesions, and advanced cases were significantly larger than those in the non-Gre group. There were also significant differences in patient age and organs resected other than the spleen between the Sp group and non-Sp group. There was no significant difference in OS between the 2 groups. The significance of Sp for upper gastric carcinoma with invasion to the greater curvature was equivocal because the patients received no survival benefit by undergoing Sp.