At ease.

Top Line: Does IMRT reduce late toxicity in patients receiving adjuvant pelvic radiation for endometrial and cervical cancer?

The Study: The initial results of RTOG 1203 (TIME-C) showed that IMRT significantly reduced acute, patient-reported GI and GU toxicity among patients receiving adjuvant radiation for cervical and endometrial cancer. The comparable PARCER trial showed a significant reduction in late GI toxicity among cervical cancer patients. Here we have late toxicity outcomes from TIME-C. As a reminder, 289 women receiving adjuvant pelvic radiation for cervical or endometrial cancer were randomized to treatment planned with 3D conformal or IMRT. At 3 years, there were no differences between IMRT and 3D for locoregional failure (3.5% v 2.2%), disease free survival (85.5% v 80.8%), or overall survival (92.4% v 97.0%). With respect to toxicity, fewer patients in the IMRT arm required anti-diarrheal medications (1.2% v 8.6%) or reported frequent diarrhea (5.75% v 15.05%) at 1 years. By 3 years, though, these differences were no longer apparent. In contrast to GI toxicity, which appears to improve over time, GU toxicity appeared to worsen in the 3D arm while improving in the IMRT arm. By 3 years, the difference in GU toxicity was significant.

TBL: IMRT reduces patient-reported GI toxicity at 1 year and GU toxicity at 3 years compared to 3D conformal treatment planning for patients receiving adjuvant pelvic radiation for endometrial or cervical cancer. | Yeung, J Clin Oncol 2022