Endocytoscopy assisted laparoscopic intraoperative diagnosis of disseminated malignancy

Abstract

An endocytoscope system is a novel accessory tool to the conventional luminal endoscope which provides 450X magnification of the gastrointestinal mucosa, thus allowing in vivo imaging of living cells (Fig. 1) [1]. It has been used with success in the evaluation of esophageal, gastric, and colorectal mucosal lesions during endoscopy [2]. First experience of its use in the intraoperative evaluation of the pancreatic ductal mucosa has also been reported [3]. However, the utility of the system in the in vivo microscopic evaluation of peritoneal lesions has not been reported yet. Two patients underwent diagnostic laparoscopy for evaluation of ascites of unknown origin. The first patient was a 45 year old woman who presented with complaints of painless distension of the abdomen associated with malaise for the past 1 month. Ultrasound of the abdomen showed ascites and thickened omentum. CT scan of the abdomen showed similar findings. The second patient was a 50 year old male patient who presented with progressive distension of the abdomen for past 3 months associated with low grade fever and weight loss. Ultrasound showed free fluid in the abdomen with thickened omentum and minimal bilateral pleural effusion. CT scan was noncontributory. Ascitic fluid examination in both the patients showed exudative ascites with low SAAG (serum ascites albumin gradient) values. Microscopic examination showed a lymphocytic picture and no atypical cells were identified. As all the above investigations were nondiagnostic, both patients underwent diagnostic laparoscopy. Both the patients were found to have moderate amount of straw colored ascites and multiple peritoneal nodules (Fig. 2A). The peritoneal nodules were biopsied and sent for histopathological examinations. Methylene blue solution, in half strength, of approximately 3–5 ml was sprayed via the laparoscope over the nodules. After the nodules were adequately stained the endocytoscope was passed into the peritoneal cavity via a 5 mm laparoscopic port (Fig. 2B). When the scope was applied in contact with the stained nodules, the intricate microscopic details of the lesions could be observed live on the video monitor. The video was relayed to the pathology department, and the pathologist helped inecognising the pathognomonic features of malignant lesions. The endocytoscopy picture in the first patient showed irregular clusters of cells with hyperchromatic nucleus and increased nuclear cytoplasmic ratio suggestive of malignancy (Fig. 3A). Similar cells were also found coursing as emboli in the capillaries of the nodules. The picture in the second patient showed cells with normal nuclear cytoplasmic ratio dispersed sparsely over the peritoneal surface, showing no evidence of malignancy (Fig. 3B). Conventional histopathological examination showed poorly differentiated carcinoma in the nodules of the first patient. The second patient was found to have granulomas suggestive of tuberculosis. With increasing experience the surgeons could make the diagnosis with accuracy without the assistance of the pathologist. The cytoscopy added an extra 5–10 minutes to the total procedure. In conclusion, the endocytoscope system when used via the laparoscope can provide on-table diagnosis of presence G. V. Rao M. J. Mansard (&) P. Rebala Department of Surgical Gastroenterology, Asian Institute of Gastroenterology, 6-3-661, Somajiguda, Hyderabad 500082, India e-mail: jeymagnus@gmail.com