Rare case of granular cell tumor of perianal region: a case report and literature review

Granular cell tumors (GCTs) are rare submucosal neoplasms, with tumors in the oral mucosa accounting for about a third of all cases. In contrast, GCT is a rare anal neoplasm, with fewer than 30 cases of perianal GCT reported in the literature. We report the case of a 36-year-old woman with a perianal lump with no obvious local lesion as the main clinical complaint. The tumor was completely resected and histologically confirmed as a GCT. The patient remained under continuous follow-up. GCT is difficult for surgeons and pathologists to diagnose, and biopsy and immunohistochemical analysis are prerequisites for an accurate diagnosis. An integrated understanding of GCT in terms of its differential diagnosis will contribute to better identification and more appropriate treatment of this disease.

Loss of histone variant macroH2A2 expression associates with progression of anal neoplasm

AimsThe macroH2A histone variants are epigenetic marks for inactivated chromatin. In this study, we examined the expression of macroH2A2 in anal neoplasm from anal intraepithelial neoplasia (AIN) to anal squamous cell carcinoma (SCC).MethodsAIN and anal SCC samples were analysed for macroH2A2 expression, HIV and human papilloma virus (HPV). The association of macroH2A2 expression with clinical grade, disease recurrence, overall survival and viral involvement was determined.ResultsmacroH2A2 was expressed in normal squamous tissue and lower grade AIN (I and II). Expression was lost in 38% of high-grade AIN (III) and 71% of anal SCC (p=0.002). Patients with AIN with macroH2A2-negative lesions showed earlier recurrence than those with macroH2A2-positive neoplasm (p=0.017). With anal SCC, macroH2A2 loss was more prevalent in the HPV-negative tumours.ConclusionsLoss of histone variant macroH2A2 expression is associated with the progression of anal neoplasm and can be used as a prognostic biomarker for high-grade AIN and SCC.