Concurrent chemo-radiation in the conservative management of breast cancer

Sequencing of chemotherapy (CTX) with radiation (RT) in the conservative management of breast cancer (CS+RT) remains controversial. We report here the results of a retrospective analysis of all patients treated with CTX and RT, with specific focus on outcome as a function of sequencing of CTX with RT.

A total of 535 patients treated with CS+RT received CTX as a component of therapy. RT was administered concurrently with CTX in 109 (CONCTX). CTX was administered before RT in 276 patients, after RT in 106 patients, and in "sandwich" fashion in 44 patients. These three groups comprise the sequential chemotherapy group (SEQCTX).

With follow-up of 8.8 years, the 10-year survival rate was 78% and the distant metastasis-free rate was 75%. Despite more adverse factors for local control, patients in the CONCTX group had superior local control rate of 92% at 10 years compared with 83% in the SEQCTX group (p < 0.001). In multivariate analysis, CONCTX was associated with a significant improvement in local control (HR = 0.338, 95% CI = 0.141-0.809, p = 0.015). Cosmetic results, toxicities, and long-term complications were acceptable using this CONCTX regimen.

CONCTX was associated with a reduction in local relapse rates, acceptable cosmesis, and toxicities. These data support the use of concurrent RT and CTX in selected patients at high risk for local failure. Future prospective trials should explore the use of concurrent CTX and RT in high-risk patients using currently employed agents.