Chemotherapy drug dose alteration due to radiation therapy in an adjuvant situation in breast cancer

Concurrent Cyclophosphamide, Methotrexate, and 5-Fluorouracil Chemotherapy and Radiotherapy for Early Breast Carcinoma

“…Several have reported a deleterious effect of RT on the ability to deliver optimum doses of CT and have suggested that this may affect treatment outcome (13)(14)(15)). An increased level of toxicity may compromise the optimal dose delivery with respect to both RT and CT (16).…”

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

“…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.…”

“…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.…”

Neutropenia febril em pacientes com câncer de mama submetidas à quimioterapia: experiência de 12 anos

“…Fiets et al, por sua vez, consideraram que o uso concomitante de CMF ou AC (doxorrubicina e ciclofosfamida) e radioterapia leva a níveis inaceitáveis de toxicidade aguda e deve ser evitado 15 . Outros autores observaram que o uso de CMF e radioterapia concomitante pode promover a necessidade de redução na dose do quimioterápico, além de culminar em menor contagem de leucócitos durante a terapia com possível atraso na terapêutica 16,17 . Além disso, não há evidências de prejuízo no tratamento de pacientes, desde que o atraso na realização da radioterapia não exceda 20 a 24 semanas da cirurgia 18 .…”