Exploring the role of SOX 2 and OCT 4 in the pathogenesis of gliomatosis peritonei: the clinicopathological profile of eleven cases.

Objective: Gliomatosis peritonei (GP) is a rare entity characterized by multiple mature glial tissue implants in association with ovarian teratomas in the peritoneum and omentum. To date, only 100 cases have been published. Not much is known about the origin, clinicopathological profile or prognosis of GP. SOX2 and OCT4 are recently recognized markers of embryonic stem cell differentiation. Here, the role of SOX2 and OCT4 in the pathogenesis of 11 cases of GP are reported and clinicopathological factors are described. Material and Methods: This was a retrospective study of six years duration (2017-2022). All the cases of GP were retrieved from archives, the diagnosis was confirmed and clinicopathological factors were noted. Immunohistochemical (IHC) investigation for glial fibrillary acid protein (GFAP) and S100 was noted wherever available. IHC for SOX2 and OCT4 was performed using an avidin-biotin technique. Results: There were 11 cases of GP identified. The median age was 29 years and 1/11 cases had nodal gliomatosis as well. There were eight cases of immature teratoma and three cases of mature cystic teratoma. SOX2 was positive in all foci of GP, while OCT4 was negative. These foci were also positive for GFAP and S100. Conclusion: A possibility of GP should be considered as a differential, clinically and radiologically, in cases of omental nodularity. Adequate sampling at the time of surgery is essential to rule out metastasis or growing teratoma syndrome. SOX2, a stem cell marker inducing neural differentiation, may play a crucial role in the development of GP in association with other transcription factors.