Follicular Induction Overlying a Cutaneous Myxoma: A Rare Case Report and Potential Diagnostic Pitfall

Cutaneous myxomas, also known as superficial angiomyxomas, are uncommon benign hamartomatous neoplasms often presenting as solitary lesions on the trunk, head and neck, or genital region. Multiple cutaneous myxomas may occur in the setting of Carney complex or its subsets, NAME and LAMB syndromes. Histologically, cutaneous myxomas are characterized as a well-circumscribed dermal or subcutaneous proliferation of variably sized fibroblasts and stellate cells within a mucinous matrix with prominent branching capillaries. An uncommon histopathologic feature demonstrated in the present case was notable follicular induction overlying the biopsied lesion. Follicular induction is a phenomenon by which primitive hair follicles and associated sebaceous glands are produced by the epithelium because of the influence of an underlying inflammatory or neoplastic dermal process. Most commonly appreciated in other benign entities such as dermatofibromas, follicular induction can be mistaken for basal cell carcinoma because of the presence of basaloid proliferations that can resemble a neoplastic process histologically in superficially sampled lesions. This case highlights the rare occurrence of follicular induction in cutaneous myxomas, provides a review of its presence in other benign neoplasms, and underscores the importance of careful clinical and histological correlation to avoid misdiagnosis as a malignant neoplasm.