Accelerated partial breast irradiation compared with whole breast radiation therapy: a breast cancer cohort study measuring change in radiation side-effects severity and quality of life.

PURPOSE: Radiotherapy (RT) after breast-conserving surgery for early-stage breast cancer patients has similar survival benefits with whole breast RT (WBRT) or accelerated partial breast irradiation (APBI). However, the impact of RT type and side-effects severity on change in quality of life (QOL) is unknown. We examined changes in RT side-effects severity and QOL by RT type.

METHODS: We analyzed data from a cohort of 285 newly diagnosed early-stage breast cancer patients with tumor size ≤3.0 cm and lymph node-negative disease. Patients (93 [32.6%] stage 0; 49 [17.2%] non-white; mean age = 59.3 years) completed four interviews (6 weeks, 6, 12, and 24 months) after definitive surgical treatment. We measured severity of RT side effects, fatigue and skin irritation, using a 5-point scale (1 "not at all" to 5 "all the time") and measured QOL using the Functional Assessment of Cancer Therapy-Breast (FACT-B) and RAND 36-item Health Survey Vitality subscale. Repeated-measures analysis of covariance of each outcome controlled for demographic, clinical/treatment, and psychosocial factors.

RESULTS: Patients initiated RT by 6 months (113 received APBI; 172 received WBRT) and completed RT by 12 months. Patients receiving WBRT (vs. APBI) reported greater increase in fatigue and skin irritation severity from 6-week to 6-month interviews (each P < 0.001). Improvement in neither total FACT-B nor Vitality differed significantly by RT type over 2-year follow-up.

CONCLUSIONS: Findings suggest that early-stage breast cancer patients can benefit from less-severe, short-term side effects of APBI with no differential impact on QOL change within 2-year follow-up.