Retroperitoneal tumors: do the satellite tumors mean something?

Primary retroperitoneal tumors constitute a rather uncommon disease with an incidence of 2 in 100,000. Local recurrence after surgical resection is reported between 60% and 90% at 10 yr. The aim of this study was to present the problem of satellite tumors around the main tumor mass and their possible relation to local recurrence.

Twenty-nine patients with retroperitoneal tumors underwent surgical resection in our department during an 8-yr period. We reviewed their records including their preoperative computed tomography (CT) scans.

Twenty patients had "complete" resections requiring seven nephrectomies, four colectomies, two splenectomies, and one appendectomy. In nine cases the resection was incomplete because of tumor invasion to vital structures. Histopathology revealed that the resected tumors were: liposarcomas (12), leiomyosarcomas (4), paragangliomas (5), malignant fibrous histiocytomas (3), other sarcomas (3), schwannoma (1), myelolipoma (1), and the malignancy grade was I in 6, grade II in 11, and grade III in 12 cases. Two patients died within 30 d of the operation. The I year recurrence rate was 41.4% (12/29) and the total recurrence rate 55.2% (16/29). Survival at 5 yr was 31% (9/29), whereas the disease-free survival was 20.7% (6/29). Four patients required reoperations. In seven cases (24,1%) preoperative CT scans revealed small nodular lesions around the main tumor that were removed en bloc and were of the same histopathological type as the main tumor. We called these "satellite" tumors. All seven patients had local recurrence within 1 yr.

There seems to be a close relationship between the finding of satellite tumors and the recurrence of the disease. The existence of satellite tumors on the preoperative CT scan may be used as a guide for the extent of the resection, and further investigations are necessary before they are used as a prognostic sign.