Influence of radiotherapy on the dose of adjuvant chemotherapy in early breast cancer

Abstract

399 patients with early breast cancer were randomly allocated to treatment by either modified radical mastectomy or lumpectomy and radiotherapy. 169 had histologically involved axillary nodes and were randomised to receive either adjuvant cytotoxic chemotherapy (76 patients) or no systemic adjuvant treatment (93 patients). Chemotherapy comprised a combination of oral cyclophosphamide and intravenous methotrexate and 5-fluorouracil (CMF) for 12 cycles over one year. Patients in the mastectomy group received a significantly higher percentage of the planned chemotherapy dose compared with those in the radiotherapy group (median 85% v. 71% p less than 0.05). Patients treated with radiotherapy were more frequently nauseated and developed more severe alopecia, but these differences were not statistically significant. At median follow-up of 37 months the relapse-rate and pattern of relapse were similar in both groups of patients receiving CMF.

Feasibility of concurrent adjuvant chemotherapy and radiotherapy after breast‐conserving surgery in early breast cancer

“…It appears that local recurrence increases when RT is delayed to deliver CT, whereas systemic recurrence increases if CT is delayed [5][6][7][8]. Concurrent administration of CT and RT seems to be an ideal option but the increased toxicity has been reported [7,9,10] and these results make physicians hesitate employing this approach in clinical practice. The current study was performed to evaluate whether the concurrent RT with CT increases the CT-associated toxicities.…”

“…In the current study, sequencing of adjuvant CT and RT had no differences in terms of common toxicities such as hematologic parameters, abnormal liver function, and RT-related adverse effects. A number of studies have reported an adverse effect of RT on the optimal dose delivery of CT when administered concurrently [5,7,[9][10][11][12][13]. They have suggested that suboptimal dose of CT due to concurrent RT could affect treatment outcome adversely.…”

Quality of adjuvant CMF chemotherapy for node-positive primary breast cancer: a population-based study

“…However, concomitant RT and Fig. 4 Relative dose intensity (median, IQR, range, outliers+/extremes*) of adjuvant CMF for patients who completed six courses according to hospital adjuvant chemotherapy have been associated with increased toxicity, and consequently impairment of RDI, and poorer cosmetic outcome in case of breast conserving surgery (Levine et al 1984;Habibollahi 1989). In our study the simultaneous administration of RT and CMF chemotherapy resulted in a relatively short median interval between surgery and the start of adjuvant chemotherapy (25 days).…”

Frequent Dose Delays and Growth Factor Requirements with the Sequential Doxorubicin-CMF Schedule

“…Although further evidence from randomized trials is needed, several trials have demonstrated that an inadequate delivery of the projected dose intensity of chemotherapy has important implications: patients receiving a dose intensity below a certain threshold value will have a higher risk of relapse and a decreased survival (1, 5). In the sequential doxorubicin-CMF schedule the large number of chemotherapy courses and the concomitant administration of radiotherapy during the C M F part of the schedule could increase the number of chemotherapy dose delays because of a slow neutrophil recovery at the day of the planned chemotherapy administration (6).…”