Characteristic MRI Findings of a Scrotal Schwannoma: A Case Report.

Scrotal schwannomas are rare benign tumors that are frequently misdiagnosed preoperatively as more common paratesticular lesions. MRI offers superior soft-tissue characterization, which can provide key diagnostic clues. We present a case of a 25-year-old male patient with a 12-year history of a scrotal mass that showed significant enlargement over the past two years. Initial scrotal ultrasound identified a solid paratesticular mass, prompting multi‑parametric MRI for detailed tissue characterization given the indeterminate nature of the lesion. Marked hyperintensity on T2-weighted imaging with a central hypointense area (the "target sign"), iso-intensity on T1-weighted imaging, and progressive heterogeneous enhancement on dynamic post-contrast sequences. These findings were highly suggestive of a benign nerve sheath tumor. The lesion was surgically excised, and histopathological examination confirmed the diagnosis of a classic schwannoma. This case underscores the pivotal role of MRI in the diagnostic workup of unusual paratesticular masses. Recognition of characteristic features, particularly the T2 "target sign" in conjunction with the specific enhancement pattern, can allow radiologists to confidently suggest the diagnosis of scrotal schwannoma preoperatively, thereby facilitating optimal surgical planning and patient counseling.