@article{2aa6f01deaa4445e83411a0c8baa9d76,
title = "Histology-tailored multidisciplinary management of primary retroperitoneal sarcomas",
abstract = "Until recently, the recommendation for primary retroperitoneal sarcomas (RPS) was to perform a complete en-bloc gross excision, (neo) adjuvant treatments being options which were not validated by randomized studies, with a large discrepancy of use between centers. The heterogeneity of RPS, with their different biological behaviour, renders a homogenous therapeutic and surgical approach probably inappropriate. Recent studies, both surgical and dedicated to adjuvant treatments, allow refining these recommendations. This review summarizes recent advances and directions.",
keywords = "Chemotherapy, Diagnosis, leiomyosarcoma, Liposarcoma, Radiotherapy, Retroperitoneal sarcoma, Retroperitoneal tumour, Solitary fibrous Tumor, Surgery",
author = "S. Bonvalot and C. Roland and C. Raut and {Le P{\'e}choux}, C. and D. Tzanis and Frezza, {A. M.} and A. Gronchi",
note = "Funding Information: Until STRASS (NCT 01344018) [5], data supporting the use of radiotherapy (RT) in primary RPS were extrapolated from its established role in extremity soft tissue sarcoma (STS) [34,35]. Phase 1 and 2 trials were reported but evaluated safety or feasibility rather than superiority over surgery alone. The results of retrospective studies were contradictory [36,37]. STRASS demonstrated that a collaborative effort across the Atlantic Ocean was feasible. The trial randomized patients to pre-operative radiotherapy 50.4 Gy plus surgery versus surgery alone. The main objective was abdominal recurrence-free survival (ARFS) defined by one of the following events: progressive disease during radiotherapy, R2 resection, or sarcomatosis found during resection, local relapse. Morbidity of pre-operative RT was acceptable, considering that 95% of patients received Intensity Modulated Radiation Therapy (IMRT). The trial was negative with 3-year ARFS of 58.7% and 60.4% in the surgery and pre-operative RT groups, respectively. As a consequence, RT cannot be considered as the standard of care for RPS. However, when STRASS was designed in 2010, the risk of progressive disease during RT and the risk to render inoperable an operable patient initially were unknown. The Independent Data Monitoring Committee (IDMC) recommended a sensitivity analysis in which local progression on RT was not regarded as a primary endpoint event when patients were finally operated despite local progression. In this sensitivity analysis, 3-year ARFS were 58.7% and 66.0% in the surgery and pre-operative RT groups. With the subsequent recognition that sarcoma histotype directly impacts on the risk of local relapse, a sub group sensitivity analysis was made on LPS patients, at higher risk of local relapse (75% of the patients included in the trial). The 3-year ARFS rates were 60.4% and 71.6% in the surgery and pre-operative RT groups. Twice as many local relapses were observed in the surgery group than in the pre-operative radiotherapy group, specifically in the LPS cohort. Further subgroup analysis by subtypes and grade suggested that pre-operative radiotherapy did not appear to be beneficial in LMS and high grade RPS. However the sub groups are individually small and should be regarded with caution. Another study dedicated to LPS only would be ideal. Median overall survival was not significantly different between the two groups, possibly because patients with LR may be re operated and because the median follow up was short (43 months), while these tumors are prone to late relapse. A longer follow up is necessary and another evaluation of the results is planned after 5 years follow up. Publisher Copyright: {\textcopyright} 2022 Elsevier Ltd, BASO ~ The Association for Cancer Surgery, and the European Society of Surgical Oncology",
year = "2023",
month = jun,
doi = "10.1016/j.ejso.2022.05.010",
language = "English (US)",
volume = "49",
pages = "1061--1067",
journal = "European Journal of Surgical Oncology",
issn = "0748-7983",
publisher = "W.B. Saunders Ltd",
number = "6",
}