Less skin toxicity in big-breasted women treated for breast cancer by radiotherapy in prone position

Treatment in the prone position decreases desquamation in women with large breast sizes receiving adjuvant radiotherapy, according to the recent research published in JAMA Oncology. The research also showed increased toxic effects using a radiotherapy boost and conventional fractionation.

Women with large breast size treated with adjuvant breast radiotherapy have a high rate of acute toxic effects of the skin. Breast radiotherapy in the prone position is one strategy that may decrease these toxic effects. In phase 3, multicenter, single-blind randomized clinical trial, the authors Danny Vesprini et. al tried To determine if breast RT in the prone position reduces acute toxic effects of the skin when compared with treatment in the supine position.

Patients from 5 centers across Canada from April 2013 to March 2018 were accrued to compare acute toxic effects of breast radiotherapy for women with large breast size (bra band ≥40 in and/or ≥D cup) in the prone vs supine positions. A total of 378 patients were referred for adjuvant RT and underwent randomization. Seven patients randomized to supine position were excluded, and 14 patients randomized to prone position were excluded.

Of the 357 women included in the analysis, 182 (51.0%) were treated in the supine position and 175 (49.0%) in prone. There was statistically significantly more desquamation in patients treated in the supine position compared with prone which was confirmed on multivariable analysis along with other independent factors ie use of boost extended fractionation and bra size.

The authors conclusively noted that treatment in the prone position should be considered for women with large breast size requiring adjuvant RT.