Gliomatosis peritonei: a series of eight cases and review of the literature

BACKGROUND Gliomatosis peritonei (GP) is a rare condition characterized by mature glial tissue implants widespread in the peritoneum. The GP is often associated with ovarian teratoma. However, little is known about the characteristics and prognosis of GP. The purpose of this study was to describe the features, treatment, and prognosis of GP. Additionally, we review previously reported cases of GP, summarizing the presently known data. METHODS From January 2000 to January 2016, cases of ovarian teratoma and GP treated at Peking Union Medical College Hospital were reviewed. We assessed the pathology, treatments, and outcomes along with prognostic information. Additionally, the literature regarding this clinical condition was also reviewed. RESULTS Eight patients met the inclusion criteria. Patients had a median age of 20 (range, 15-25) years. GP was diagnosed as the primary tumor in 6 patients and at a secondary surgery in two patients. The primary ovarian tumor consisted of immature teratoma (n = 7) and mature teratoma (n = 1). Grades of immature ovarian teratoma were 2, grade 1; 3, grade 2; and 2, grade 3. Tumors mean had a size of 20.4 (range, 11-30) cm. The median follow-up time was 60.5 (range, 3-144) months. All cases had conservative surgery and seven of them had macroscopic residual disease postoperatively. During the study period, the eight patients remained alive and asymptomatic. Three patients in the study experienced spontaneous pregnancy. After reviewing the existing literature, a total of 14 patients with nodal gliomatosis were present and 10 of them were alive. According to the literature review, five articles reported more than five cases. Of a total of 67 patients, 60 of them remained alive. CONCLUSION The prognosis of immature ovarian teratoma with GP is favorable. Complete resection of GP is often difficult. Residual peritoneal disease in GP can be asymptomatic and quiescent over a long period. A more conservative surgical approach may be carried out in patients with massive peritoneal spread after the presence of metastatic immature elements is excluded. Owing to the risk of recurrence and malignant transformation of GP, a long-term follow-up is necessary for patients with residual peritoneal disease.