Quality of life outcomes associated with optimization of treatment by omitting radiotherapy in early breast cancer.

Purpose Improved prognosis of early breast cancer (EBC) has created opportunities for treatment optimization but reducing morbidity should not inadvertently compromise quality of life (QoL). PROSPECT1 used preoperative MRI and pathology findings to identify women suitable for radiotherapy (RT) omission following breast conserving surgery. We retrospectively explored the association between de-escalation by omission of RT and QoL in women with EBC. Materials and methods Three groups were recruited: PROSPECT participants who omitted RT following preoperative MRI (A); participants who received RT following preoperative MRI (B); and women who received usual care- No MRI, received RT (C). Measures included the EORTC QLQ-C30 and BR23, BCTOS, DASS-21 and a measure of decision regret. Between group differences were assessed using ANOVA or non-parametric equivalents. Semi-structured interviews were analysed with qualitative description (n=44). Results Data from 400 women were analysed (125A, 102B, 173C). Group A had fewer symptoms and better body image (breast symptoms: A-B p=.003, A-C p=<.001; arm symptoms: A-B p=.004, A-C p=.011; body image: A-C p=.041) and fewer differences between the treated and untreated breasts (cosmetic: A-B p<.001, A-C p<.001; functional: A-C p=.011; breast specific pain: A-B p<.001, A-C p<.001). Two qualitative themes were found: Treatment with the biggest impact on QoL, and Specific impact of RT on QoL. Conclusions Omission of RT was associated with better QoL and functional and cosmetic outcomes. It was highly acceptable to patients. Clinicians should consider the potential for preserved QoL associated with treatment optimization via omission of RT in treatment planning for patients with EBC. Micro abstract Following on from PROSPECT[ANZ:1002], we compared women with early breast cancer (EBC) who omitted RT (n=125) with women who received RT(n=175) on quality of life (QoL) outcomes. Omission of RT was consistently associated with superior QoL and was highly acceptable to patients. If recurrence is low in select women with EBC who omit RT, QoL may influence treatment planning.