Condition mimicking peritoneal metastasis associated with preoperative staging laparoscopy in advanced gastric cancer

Preoperative staging laparoscopy is used to search for peritoneal dissemination or distant metastasis as part of the treatment strategy for advanced gastric cancer. We observed pseudo-peritoneal metastasis during laparotomy in 6 of 49 patients in whom lack of peritoneal dissemination had been confirmed by preoperative staging laparoscopy. In all cases, suspected nodules were biopsied and subjected to rapid histological diagnosis. However, a definite malignant or benign diagnosis could not be obtained via a rapid histological examination during surgery. A final histological examination combined with immunohistological analysis using formalin-fixed embedded tissues confirmed no malignancy after surgery in all cases. These rapidly growing nodules that mimic peritoneal metastasis are thought to be associated with the use of grasping forceps during staging laparoscopy. No cases have been reported in which peritoneal nodules mimicking peritoneal metastasis occurred after staging laparoscopy, and surgeons should consider this possibility in patients treated shortly after staging laparoscopy.