Top Line: Do patients with soft tissue sarcoma who have a complete response to neoadjuvant radiation have better survival outcomes?
The Study:Neoadjuvant radiation reduces the risk of local recurrence after resection of soft tissue sarcoma with a lower risk of late toxicity than adjuvant RT. Another benefit is that some patients have a good response to RT that may improve resectability, and some patients may even have a pathologic complete response. Do patients who have a pCR have better survival outcomes? RTOG 9514 was a single arm phase 2 trial where patients with high grade STS ≥8 cm of the extremity or trunk received neoadjuvant chemoradiation consisting of 3 cycles of MAID interdigitated with a split course of 44 Gy in 22 fractions. RTOG 0630 was a single arm, phase 2 trial of image guided RT with reduced margins for extremity STS. This study combined data from both trials (n=143 patients) to determine if pCR was prognostic of survival outcomes. The pCR rates were 27.5% in 9514 and 19.4% in 0630. Among patients who had a pCR across both trials, the rate of 5-year OS was 100%, which was significantly higher than OS for patients who didn’t have a pCR. For the latter, 5-year OS was 76.5% in 9514 and 56.4% in 0630. Likewise, the rate of local failure was 0% after a pCR in both trials compared to 11.7% for TBL: In two RTOG trials of neoadjuvant RT and chemoRT for STS, patients who had a pCR had better overall survival and lower risk of recurrence than patients with residual tumor. | Wang, JAMA Oncol 2023
The Study:Neoadjuvant radiation reduces the risk of local recurrence after resection of soft tissue sarcoma with a lower risk of late toxicity than adjuvant RT. Another benefit is that some patients have a good response to RT that may improve resectability, and some patients may even have a pathologic complete response. Do patients who have a pCR have better survival outcomes? RTOG 9514 was a single arm phase 2 trial where patients with high grade STS ≥8 cm of the extremity or trunk received neoadjuvant chemoradiation consisting of 3 cycles of MAID interdigitated with a split course of 44 Gy in 22 fractions. RTOG 0630 was a single arm, phase 2 trial of image guided RT with reduced margins for extremity STS. This study combined data from both trials (n=143 patients) to determine if pCR was prognostic of survival outcomes. The pCR rates were 27.5% in 9514 and 19.4% in 0630. Among patients who had a pCR across both trials, the rate of 5-year OS was 100%, which was significantly higher than OS for patients who didn’t have a pCR. For the latter, 5-year OS was 76.5% in 9514 and 56.4% in 0630. Likewise, the rate of local failure was 0% after a pCR in both trials compared to 11.7% for TBL: In two RTOG trials of neoadjuvant RT and chemoRT for STS, patients who had a pCR had better overall survival and lower risk of recurrence than patients with residual tumor. | Wang, JAMA Oncol 2023