A 46-year-old multiparous (gravida 3, para 3) woman presented to her primary care provider with a palpable vulvar polypoidal mass, measuring 7 cm in greatest dimension. The mass was painless and had been growing in size over the past 2 years. Her medical history was remarkable for obesity, hypothyroidism, and an appendectomy at age 17. Her family history was significant for a sister with breast cancer, diagnosed at age 34. A core biopsy was performed.
What did the core biopsy show?
Dr. Amy Storfa: Hematoxylin and eosin-stained sections of the core biopsy showed a tumor composed of relatively small, uniform spindle cells with eosinophilic cytoplasm and bland nuclei with no appreciable cytologic atypia. The background showed various numbers of medium- to large-sized blood vessels, some with focally hyalinized walls (Figure 1A, 1B). Mitotic figures were not identified. Immunohistochemical stains for smooth muscle actin, desmin, vimentin, estrogen receptor, and progesterone(Drug information on progesterone) receptors were positive; an immunohistochemical stain for S-100 was negative. The diagnosis was aggressive angiomyxoma, also known as deep angiomyxoma.
Figure 1: Polypoid Lesions of the Lower Female Genital Tract—
What were the operative findings?
Dr. Susan Davidson: A rubbery, gelatinous 10-cm mass was located in the left labia majora with extensive infiltration into the surrounding soft tissue.
What did pathologic examination of the mass show?
Dr. Meenakshi Singh: Gross examination revealed a yellow-tan ill-defined soft-tissue mass measuring 10 X 5.1 X 3.2 cm. The cut surface of the mass had a grey-pink gelatinous appearance; the edge of the lesion showed infiltration into the surrounding soft tissue. Hematoxylin and eosin-stained sections of the mass showed a poorly circumscribed tumor with extension into the surrounding connective tissue. Cytologically, the tumor showed histologic features similar to those seen in the biopsy. The surgical margin was uninvolved by tumor. The final diagnosis was aggressive angiomyxoma.
What are the clinical features of aggressive angiomyxoma?
Dr. Davidson: Aggressive angiomyxomas involve the deep soft tissue of the vulvovaginal region, pelvis, and perineum. They virtually never metastasize, but rather, infiltrate locally into these regions with potential for recurrence and localized destruction. Magnetic resonance imaging studies are often obtained to assess for local extension. Approximately 30% to 40% of the lesions recur, and lesions may grow to over 20 cm. Women in the third to fifth decade of life are almost exclusively affected. However, some cases have been reported in the inguinoscrotal area in men. Clinically, these may be mistaken for a cystic lesion like a Bartholin's cyst or a hernia.[1,3] These lesions are rare, and no specific risk factors have been described in their development.