Feasibility of prior administration of cyclophosphamide in TC combination treatment

Abstract

TC (docetaxel 75 mg/m(2) and cyclophosphamide 600 mg/m(2) q3w) combination is used for neoadjuvant/adjuvant chemotherapy in primary breast cancer. The incidence of allergic reaction is reportedly more common in patients who receive docetaxel before cyclophosphamide. This study aims to determine the significance of cyclophosphamide and docetaxel administration sequence. Prospective analysis was performed of 49 consecutive patients treated with TC for stage I-IIB breast cancer from March 2010 to June 2011. Premedication was administered with granisetron, dexamethasone, and chlorpheniramine. Patient charts were reviewed for completion rate and adverse events. Two-tailed Fisher exact test was used to evaluate adverse events between prior cyclophosphamide and prior docetaxel. Of 49 patients, 26 received docetaxel prior to cyclophosphamide and 23 received cyclophosphamide before docetaxel. There were no differences in patient characteristics between the two groups. Completion rates were 95.6 % in the prior cyclophosphamide group, and 100 % in the prior docetaxel group. The relative dose intensities of docetaxel and cyclophosphamide were 94.5 and 94.8 % in the prior cyclophosphamide group, and 98.5 and 98.7 % in the prior docetaxel group (p < 0.01). In the prior cyclophosphamide group, severe neutropenia occurred in 96 % of patients, but in only 46 % of patients in the prior docetaxel group (p < 0.01). Significantly fewer cases of skin eczema (27 versus 61 %), nausea (8 versus 48 %), stomatitis (23 versus 61 %), and diarrhea (4 versus 30 %) were observed in the prior docetaxel group as compared with the prior cyclophosphamide group (p < 0.01). Decreased incidences of fatigue (50 versus 65 %) and edema (19 versus 35 %) were found in the prior docetaxel group (p < 0.05). No difference was observed in allergic reaction or neuropathy between the two groups. Patients receiving cyclophosphamide prior to docetaxel were at increased risk of several toxicities as compared with patients receiving docetaxel prior to cyclophosphamide in TC combination therapy.