Pyogenic Granuloma of the Buccal Mucosa Mimicking an Atypical Vascular Tumor: A Case Report

Background: Pyogenic granuloma (PG) is an uncommon vascular proliferation that, when it arises intraorally, is predominantly gingival; buccal mucosal involvement is rare. Extragingival PG in elderly patients may mimic malignant vascular tumors. Methods: We report a 69-year-old woman with a 1.0 cm ulcerated mass of the left lower buccal mucosa that enlarged after biting trauma. The excised lesion was examined histopathologically and by immunohistochemistry for CD31, CD34, D2-40, S100, human herpesvirus 8 (HHV-8), Ki-67, and p53. Reports of buccal mucosal PG published up to December 2025 were reviewed. Results: The initial pathology report described an atypical vascular tumor with involved margins, requiring exclusion of hemangioendothelioma, angiosarcoma, and Kaposi sarcoma. Immunohistochemistry showed diffuse CD31 and CD34 positivity and preserved S100-positive perilesional nerve bundles, with absent HHV-8, a low Ki-67 index, and no aberrant p53 expression; the diagnosis was formally amended to PG. No recurrence occurred at 9 months despite involved margins. Among 11 previously reported cases, recurrence was documented in 6, none of which recurred. Conclusions: Buccal mucosal PG may mimic vascular malignancy in elderly patients, and immunohistochemistry can be decisive. Whether prognosis differs by site remains an open question requiring larger series.