Aggressive Angiomyxoma of the Vulva Mimicking a Benign Mass: A Case Report

Aggressive Angiomyxoma (AA) is a rare, slow-growing mesenchymal neoplasm predominantly affecting women of reproductive age, characterised by local infiltration and a high recurrence rate. The present case presents a 32-year-old woman with a vulvar mass persisting for three years, initially misdiagnosed as a Bartholin’s cyst upon clinical examination. Magnetic Resonance Imaging (MRI) revealed a well-defined, hyperintense mass on T2-weighted imaging with a characteristic laminated internal architecture, displacing adjacent structures with limited invasion of the underlying musculature and without significant infiltration of the urogenital diaphragm or pelvic organs. Complete surgical excision was achieved with a margin of 1 cm. Histopathology demonstrated a sparsely cellular myxoid tumour composed of spindle and stellate cells in a loose matrix with prominent vasculature. Immunohistochemical analysis showed strong positivity for Oestrogen Receptors (ER) and Progesterone Receptors (PR), vimentin and focal desmin, while S-100 expression was negative. Given the hormone receptor profile, the patient was initiated on adjuvant Gonadotropin-Releasing Hormone (GnRH) agonist therapy to reduce recurrence risk, administered once a month for 12 months. She remained recurrencefree at six-month follow-up. The present case underscores the diagnostic challenge posed by AA, which can closely resemble benign lesions such as Bartholin’s cysts and fibroepithelial polyps, as well as malignant neoplasms like myxoid liposarcoma, necessitating a high index of suspicion and thorough histopathological evaluation for accurate diagnosis. Accurate diagnosis requires integration of clinical, radiological and histopathological findings. The infiltrative nature of the tumour, despite its bland cytology, necessitates complete resection and prolonged surveillance. Hormonal therapy represents a valuable adjunct in receptorpositive cases, especially when surgical margins are uncertain or complete excision is infeasible.