Two-year results from an ongoing international trial show that women with non-low-risk ductal carcinoma in situ (DCIS) report some poorer cosmetic and functional outcomes when they receive a tumour bed radiotherapy boost.

The findings should help oncologists discuss therapy options with their patients, say the authors, led by Professor Madeleine King, Australian cancer chair of cancer quality of life at the University of Sydney.

The results come from an interim analysis of the BIG 3-07/TROG 07.01 trial, in which 1208 women with DCIS who had breast-conserving surgery, followed by whole breast radiotherapy, were randomised to either receive tumour bed boost or not.

It was the first substantial evidence on patient reported outcomes following local therapies for DCIS, the researchers said.