# STRASS (EORTC 62092)

Source: https://onco.cc/trials/strass/  
OnCo record `strass` (Trial). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

The first randomised trial in retroperitoneal sarcoma found that radiotherapy before surgery did not reduce recurrence in the abdomen, ending a decades-long debate for most patients.

## Summary

STRASS, EORTC 62092, randomised 266 patients with primary resectable retroperitoneal sarcoma across European and North American sarcoma centres to preoperative radiotherapy followed by surgery or surgery alone. Its primary endpoint of abdominal recurrence-free survival was not improved by radiotherapy, and preoperative treatment added toxicity and delayed surgery. An unplanned subgroup analysis suggested a benefit in well-differentiated and low-grade dedifferentiated liposarcoma, which continues to be studied but did not change the primary result. Published in Lancet Oncology in 2020, it made surgery alone the standard for most retroperitoneal sarcomas and shifted attention to neoadjuvant chemotherapy (STRASS2).

## Fields

- Kind: Trial
- Status: negative
- Last checked: 2026-09-17
- Tags: subtype-page
- Registry id: NCT01344018
- Phase: 3
- Setting: Primary resectable retroperitoneal sarcoma: preoperative radiotherapy (50.4 Gy) plus surgery versus surgery alone
- Sponsor: EORTC
- Enrolled: 266
- Result: Abdominal recurrence-free survival not improved by preoperative radiotherapy; possible benefit in liposarcoma subgroups only.

## Sources

- ClinicalTrials.gov NCT01344018: https://clinicaltrials.gov/study/NCT01344018
- Lancet Oncology 2020: https://doi.org/10.1016/S1470-2045(20)30446-0

## Connected records

- cancers: [Leiomyosarcoma](https://onco.cc/cancers/leiomyosarcoma/), [Liposarcoma](https://onco.cc/cancers/liposarcoma/), [Retroperitoneal sarcoma](https://onco.cc/cancers/retroperitoneal-sarcoma/), [Sarcomas (soft tissue, bone, GIST)](https://onco.cc/cancers/sarcoma/)
- technologies: [IMRT / IGRT (modern external beam)](https://onco.cc/technologies/imrt-igrt/)

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