Paratesticular liposarcoma: a clinicopathologic study.

Paratesticular liposarcomas are rare and typically reported as isolated cases or as components of larger studies of liposarcomas. We studied a series of these tumors. All cases of paratesticular liposarcomas were retrieved from the archives of the Royal Marsden Hospital and the Johns Hopkins Hospital. Slides were reviewed and clinical information obtained. There were 30 paratesticular liposarcomas from men aged 41-87 years (mean 63 years; median 65 years) that involved the spermatic cord (23, 76%), testicular tunics (6, 20%), and epididymis (1, 4%). Tumors ranged from 3 to 30 cm (mean 11.7 cm; median 10 cm). Nineteen were well-differentiated liposarcomas (WDLs) and 10 were dedifferentiated liposarcomas (DDLs, five with high-grade and five with low-grade dedifferentiation). One was a myxoid/round cell liposarcoma with 70% round cell areas. All patients were treated by radical orchiectomy. One patient with WDL received radiation after his second recurrence and the myxoid/round cell liposarcoma received radiation and chemotherapy. Follow-up information was available for 16 of the patients, including 10 WDLs (range 24-216 months, mean 106 months), 5 DDLs (14-30 months, median 24 months), and for the myxoid/round cell liposarcoma (14 months) (range for all cases 14 months to 22 years; mean 87 months, median 36 months). Six of the WDLs (60%) recurred at 2, 4, 6, 10, 18, and 21 years (median 8 years). The lesion that recurred at 18 years (case no. 6) displayed foci of high-grade dedifferentiation in the recurrence, although the patient was disease free at 19 years. One patient with WDL had two recurrences at 4 and 7 years, and another had six recurrences over a 17-year period. Only one example of DDL recurred, at 30 months; another patient, who refused therapy for 15 years, had a primary tumor 30 cm in diameter, displayed pulmonary metastases 1 month after excision, and died after 14 months. The patient with MRCL had abdominal metastases after 1 year and was alive at 14 months. In summary, paratesticular WDL had a prolonged course with recurrences in more than half the cases, sometimes late. There were no metastases and the overall prognosis was good. One DDL recurred and only one of five (20%) developed metastases, but the mean follow-up for DDL was only 24 months.