Pathologic Response After Weekly Paclitaxel versus Docetaxel in Operable Breast Cancer.

Introduction: Weekly paclitaxel (Ptx) and q3w docetaxel (Dtx) are equivalent in adjuvant breast cancer treatment. Weekly Ptx is better tolerated than q3w Dtx and became the first choice in daily practice, even preoperatively.

Methods: To compare the efficacy and safety of the two regimens, a retrospective analysis was performed in breast cancer patients (pts) referred for neoadjuvant, sequential, taxane-containing chemotherapy to the Institute of Oncology and Oncofort Clinic, Bucharest, between 2008 and 2017.

Results: Forty-seven cases were eligible, median age was 56 years (34-73 years), mainly stage IIIA-B (53.2%, 25 pts) and ductal invasive (70.2%, 33 pts) of which 24 pts (51%) received q3w Dtx and 23 pts (48.9%) weekly Ptx. The histological response rates were 62.5% (15 pts) and 73.7% (17 pts) (p=0.47), average dose-intensity was 87.7% and 96.7% (p=0.002) and grade III-IV toxicity rate was 12.5% and 13% (p=0.64), respectively. Pathologic response was correlated with immunophenotype, PgR expression, tumor size and backbone chemotherapy (p<0.05).

Discussion: Our study showed an improved efficacy of taxane's weekly administration, probably due to a better tolerance and a lower rate of dose-impairing toxicities.