Intratesticular serous cystadenoma of borderline malignancy. A pathological, histochemical and DNA content study of a case with long-term follow-up.

A 61-year-old man presented with a painless right testicular swelling of 6 months duration. A right orchiectomy was performed and pathological examination showed an intratesticular serous borderline tumour (SBT). Immunohistochemical staining was positive for carcinoembryonic antigen, LeuM1, B72.3, S100-protein, Ca125, cytokeratins AE1/AE3 and vimentin, suggesting a Müllerian origin or differentiation. DNA image analysis revealed an aneuploid histogram. The favorable outcome of the patient confirms that testicular SBTs behave as non-aggressive tumours, even when characterized by aneuploid DNA content.