Recurrence patterns after resection of retroperitoneal sarcomas: An eight‐institution study from the US Sarcoma Collaborative

Abstract

Background and Objectives: Resection of primary retroperitoneal sarcomas (RPS) has a high incidence of recurrence. This study aims to identify patterns of recurrence and its impact on overall survival. Methods: Adult patients with primary retroperitoneal soft tissue sarcomas who underwent resection in 2000–2016 at eight institutions of the US Sarcoma Collaborative were evaluated. Results: Four hundred and ninety-eight patients were analyzed, with 56.2% (280 of 498) having recurrences. There were 433 recurrences (1–8) in 280 patients with 126 (25.3%) being locoregional, 82 (16.5%) distant, and 72 (14.5%) both locoregional and distant. Multivariate analyses revealed the following: Patient age P = .0002), tumor grade (P = .02), local recurrence (P = .0003) and distant recurrence (P < .0001) were predictors of disease-specific survival. The 1-, 3-, and 5-year survival rate for patients who recurred vs not was 89.6% (standard error [SE] 1.9) vs 93.5% (1.8), 66.0% (3.2) vs 88.4% (2.6), and 51.8% (3.6) vs 83.9% (3.3), respectively, P < .0001. Median survival was 5.3 years for the recurrence vs 11.3+ years for the no recurrence group (P < .0001). Median survival from the time of recurrence was 2.5 years. Conclusions: Recurrence after resection of RPS occurs in more than half of patients independently of resection status or perioperative chemotherapy and is equally distributed between locoregional and distant sites. Recurrence is primarily related to tumor biology and is associated with a significant decrease in overall survival.

Single centre 30‐year experience in treating retroperitoneal liposarcomas

“…Histological grade was predictive of metastasis with grade 3 tumors having a 16‐fold higher risk of developing metastases than grade 1 tumors. Histological subtypes of retroperitoneal liposarcoma have been suggested to have different metastatic potential but we did not observe this 4,8,9 . Metastases were rare in our patient group with a 5‐year metastases‐free survival of 80%.…”

“…Histological subtypes of retroperitoneal liposarcoma have been suggested to have different metastatic potential but we did not observe this. 4,8,9 Metastases were rare in our patient group with a 5-year metastases-free survival of 80%. In 5 (5%) patients, the metastases were extensive at the time diagnosis and no operative treatment was offered.…”

“…While all retroperitoneal liposarcomas tend to recur locally, the metastatic potential of the tumor increases with dedifferentiation. [3][4][5][6][7][8][9] Resection with tumor-free margin is the cornerstone of sarcoma treatment and has been proposed the most important factor in overall survival as well as local disease control. 4,6,7,[9][10][11] Retroperitoneal location can, however, limit the extent of feasible resection and is associated with worse local disease control and survival.…”

“…The subtypes differ in their clinical course with lipoma‐like liposarcomas and dedifferentiated liposarcomas being common in the retroperitoneum while myxoid and pleomorphic tumors occur more often in the extremities. While all retroperitoneal liposarcomas tend to recur locally, the metastatic potential of the tumor increases with dedifferentiation 3‐9 …”

Long-term survival by repeat resection for metastases from primary retroperitoneal leiomyosarcoma: A case report

“…The gold standard treatment for sarcoma is complete resection, and a 50% 5-year overall survival (OS) rate can be achieved by curative surgery [ 3 ]; however, the recurrence rate is relatively high (>50%). The treatment for sarcoma recurrence remains unclear, and multiple metastases and unresectable states are associated with a poor prognosis [ 4 , 5 ]. If the recurrence site is completely resectable, the OS is improved after the curative resection [ 6 ].…”