Retroperitoneal sarcoma: is it time to change the surgical policy?

Complete tumor resection is the mainstay of treatment for retroperitoneal sarcoma (RPS), but the size and quality of surgical margins for radical resection in RPS are unknown. They are believed to be pushing tumors, but recently, aggressive surgical policies leading to multivisceral resection have seemed to suggest better local control compared with simple tumor resection. We analyzed a single-institution series of RPS to provide information useful to surgical decision-making.

From 1996 to 2008, 77 patients referred to our institution underwent surgery for primary RPS. Thirty tumors were classified as liposarcoma, and 20 as leiomyosarcoma. Potential prognostic factors were tested retrospectively. Number and pathologic status of resected organs were assessed.

151 organs were resected. Ninety-two were involved by the tumor (60.9%). Liposarcoma involved 48 of 77 organs resected for this histotype (62.3%). Infiltrative pattern was observed in 39/92 organs, and expansive pattern in 53/92 viscera. The infiltrative pattern was more often observed in leiomyosarcoma and non-lipogenic tumors. The expansive pattern was more often observed in liposarcoma. Psoas was the organ most often involved by infiltrative pattern (12/14); the kidney was the organ most often involved by expansive pattern (19/28). 80% of patients had at least one viscera infiltrated by the tumor.

This series, in which an aggressive surgical policy was adopted along with extensive pathologic sampling, shows that RPS has a high rate of viscera infiltration. This growth pattern is characteristic of well-differentiated liposarcoma too. These pathologic data should be considered when planning surgical strategy.