Gastric carcinoma and peritoneal mesothelioma – a rare case of synchronous cancer. Clinical observation

Abstract

Primary-multiple malignant neoplasms develop in about 9 % of cancer patients in the Russian Federation, while synchronous tumors are detected in a quarter of them, which dictates the need for a mandatory multidisciplinary approach to the choice of treatment. Localization of synchronous primary-multiple tumors in one anatomical zone requires a qualitative interpretation of instrumental diagnostic methods and morphological analysis after biopsy of each tumor. Along with this, there is a possibility of an erroneous opinion about the presence of different histological structures of the detected tumors and the data of visual assessment methods are interpreted in favor of a single disease.This paper presents a clinical observation of a rare combination of gastric adenocarcinoma and peritoneal mesothelioma. The case was discussed at a multidisciplinary consultation with the participation of a surgeon, a chemotherapist and a radiologist. Taking into account the clinical stage of gastric body cancer c T3N1M0, III stage, it was decided to conduct preoperative polychemotherapy at the first stage. Repeated diagnostic laparoscopy revealed no negative dynamics, multiple small dropouts in the peritoneum persisted. Subsequently, the operation was performed in the volume of gastrectomy, total parietal peritectomy and appendectomy without macroscopic signs of a residual tumor. It was decided to refrain from intra-abdominal chemoperfusion with hyperthermia due to the large volume of surgery and the previous 8 courses of polychemotherapy. Microscopic examination of the altered part of the stomach wall revealed residual adenocarcinoma (type according to Lauren – intestinal) with signs of therapeutic pathomorphosis G3 (according to Mandard), which had grown into the subserous layer and the fiber of the small omentum, with signs of perineural invasion, in the absence of vascular invasion; resection edges – R0. On the surface of the removed fragments of the peritoneum, various foci of malignant epithelioid mesothelioma were found. At the control examination a year later, according to computed tomography and esophagogastroduodenoscopy, there were no signs of progression, the patient’s condition was satisfactory.