Is the timing of radiotherapy after breast conservation surgery for early stage cancer important?

Concurrent CMF and radiation therapy for early stage breast cancer: results of a pilot study

PURPOSE

The optimal sequencing of chemotherapy (CT) and radiotherapy (RT) for patients with early-stage breast cancer treated with breast-conserving therapy is unresolved. Given the concerns arising from delaying either CT or RT, we conducted a pilot study of a concurrent CT-RT regimen in the hope that this would reduce side effects without decreasing efficacy.

METHODS AND MATERIALS

From 1992-1994, 112 patients with 0-3 positive nodes received 6 monthly cycles of classic oral chemotherapy with cyclophosphamide, methotrexate, and 5-fluorouracil (5-FU) (CMF). On day 15 of cycle 1, patients started tangential field RT (39.6 Gy in 22 fractions), followed by a 16 Gy boost in 8 fractions. Median follow-up time for surviving patients was 53 months.

RESULTS

Moist desquamation developed during or shortly after RT in 50% of patients, but only 5 patients required treatment breaks. Grade 4 neutropenia during RT occurred in 16 patients, but only 1 required hospitalization. One patient developed Grade 2 radiation pneumonitis. Ninety-three percent of patients received at least 85% of prescribed drug doses. Cosmetic scores of 51 evaluable patients approximately 2 years after the end of chemotherapy were 47% excellent, 43% good, and 10% fair. We have observed 4 local failures and 20 distant failures.

CONCLUSIONS

This concurrent CT-RT scheme had acceptable toxicity and outcome. Further comparison of this approach allowing prompt initiation of both CT and RT to alternative sequences is warranted.