Sclerosing peritonitis associated with gynecological tumors: IgG4 peritoneal disease or a low grade spindle cell neoplasm?

Abstract

Introduction: Sclerosing peritonitis is a fibro-inflammatory condition of the peritoneum which is rarely associated with ovarian neoplasia e.g., thecoma. The etiology is largely unknown. Objective: To investigate whether sclerosing peritonitis associated with gynecological neoplasia is a reactive process and part of the spectrum of IgG4-related disease, or a neoplastic process and harboring molecular alterations known to occur in low-grade spindle cell neoplasms. Methods: Six cases of sclerosing peritonitis and ovarian neoplasia were identified from the consultation files. Pathology materials were reviewed and select sclerosing peritonitis sections were stained with IgG and IgG4 immunohistochemical markers. Formalin-fixed paraffin-embedded tissue samples underwent RNA-sequencing using the Illumina TruSight RNA fusion assay. Results: No case had an IgG:IgG4 positive ratio of >40% or met the additional criteria necessary to diagnose an IgG4-related disease. No characteristic spindle cell neoplasia -associated gene-fusions or chromosomal rearrangements, such as translocations or deletions, were identified on the sequencing platform. Conclusion: Our investigations do not support an IgG4-related disease or low grade spindle cell neoplasia as the etiology of the sclerosing peritonitis associated with ovarian neoplasia.

Keywords

• Sclerosing peritonitis
• Ovarian neoplasia
• IgG4-expression
• Molecular alteration