(P 336) EVOLUTION AND PURSUIT OF EXCELLENCE IN SARCOMA MANAGEMENT IN AN ASIAN TERTIARY SARCOMA SPECIALISED CENTRE

Objective: To broadly characterise all soft tissue and visceral sarcoma resections in Singapore General Hospital (SGH) and National Cancer Centre Singapore (NCCS) across a period of 20 years and delineate the evolution of sarcoma care through a focus on retroperitoneal sarcoma (RPS) resections, comparing postoperative outcomes and overall survival (OS) of RPS patients pre and post establishment of the Department of Sarcoma, Peritoneal and Rare Tumours (SPRinT) in 2018, one of the few dedicated subspecialized units in Southeast Asia that treats sarcoma. We aim to underscore the foundational elements needed for the establishment of analogous units as a reference for other upcoming sarcoma centres.

Methods: All patients who underwent soft tissue or visceral sarcoma resections at SGH and NCCS over a 20-year period from February 2002 to October 2022 were identified and retrospectively reviewed from a prospectively maintained database. Patient, tumour and treatment characteristics were summarised for these patients. For RPS patients, additional parameters such as postoperative outcomes, median survival and surgical subspecialty involvement were summarised.

Results: 899 patients were included in this study. 389 (43.3%) patients had soft tissue sarcomas (STS) and 510 (56.7%) patients had visceral sarcomas with a majority achieving R0/R1 margin status (n= 739, 82.2%). 112 (12.5%) patients had RPS with 77 (8.6%) treated before and 35 (3.9%) treated after the establishment of SPRinT. RPS patients treated pre and post establishment of SPRinT were similar in patient and tumour characteristics. Post-SPRinT RPS patients underwent more multivisceral resections with 30 (85.8%) patients having 2 or more organs resected as compared to 26 (33.8%) in the pre-SPRinT group. Increased surgical subspecialty collaboration was observed in the care of RPS patients post-SPRinT, especially with vascular (51.4% vs 3.9%) and urology teams (28.6% vs 15.6%). For postoperative outcomes, 30-day mortality and need for reoperation were low in both groups, however the proportion of patients with more severe postop complications (Clavien-dindo score ≥3) was greater for pre-SPRinT as compared to post-SPRinT RPS patients (28.6% vs 17.1%). Kaplan-Meier analysis revealed no significant difference in 2-year OS between both groups. Median OS was not reached for majority of the patients and a longer follow-up is needed to delineate between the groups.

Conclusion: SPRinT is a dedicated subspecliaized unit that was created to treat sarcoma from a multidisciplinary angle in order to provide the best outcomes for our patients. The evolution of sarcoma management across 20 years in SGH and NCCS as delineated through the specific example of RPS care pre and post the establishment of SPRinT demonstrates the imperative for all sarcoma patients to be referred to and be managed in a centralised, dedicated high volume centre with a specialised surgical unit and multidisciplinary tumour board (MTB) in order to achieve optimal postoperative outcomes, in accordance with recommendations from international guidelines.