MRI assessment of locoregional extent in a Buschke–Löwenstein tumor with histopathologically confirmed malignant transformation: A case report

Abstract

The Buschke-Löwenstein tumor (BLT), also designated giant condyloma acuminatum, represents a rare anogenital neoplasm of intermediate biological behavior, occupying a nosological boundary between benign condylomatous disease and invasive squamous cell carcinoma (SCC). Its malignant transformation potential, estimated between 30% and 56%, renders early diagnosis and accurate locoregional staging of paramount clinical importance. We report the case of a 54-year-old immunocompetent male who presented with a 2-year history of a progressively enlarging scrotal mass, ultimately measuring 12 cm at clinical assessment. Physical examination disclosed a large exophytic cauliflower-shaped lesion with surface ulceration, malodorous discharge, and bilateral inguinal lymphadenopathy. Pelvic MRI revealed a heterogeneous scrotal mass with posterior extension into the ipsilateral intergluteal fold and perineal soft tissues. Post-contrast T1-weighted sequences demonstrated avid heterogeneous enhancement. Diffusion-weighted imaging yielded a markedly reduced mean apparent diffusion coefficient value of 0.9 × 10⁻³ mm²/s within the inguinal lymph nodes, a finding supportive of, though not independently diagnostic of, nodal metastatic involvement, which was subsequently confirmed by fine-needle aspiration cytology. Histopathological examination of the surgical specimen identified a dual pattern comprising benign condylomatous areas alongside foci of invasive moderately differentiated SCC, confirming malignant transformation. This case underscores the oncological risk inherent to long-neglected anogenital condylomatous lesions and highlights the pivotal contribution of pelvic MRI—particularly diffusion-weighted sequences with ADC quantification—in delineating locoregional tumor extent, raising suspicion for nodal metastatic involvement, and guiding surgical planning in the management of Buschke–Löwenstein tumor.