Background

Obese patients are often not fully dosed when receiving adjuvant chemotherapy for breast cancer, which might influence the inferior outcomes seen in this patient population. Current guidelines recommend full, weight-based dosing of chemoherapy for obese patients. The aim of the present study was to assess toxicity and deliverable dose intensity in patients treated with adjuvant chemotherapy for breast cancer.

Patients and Methods

We conducted a single-center retrospective case review on patients treated with adjuvant chemotherapy for early breast cancer at our institution from 2009 to 2012. Data were extracted from electronic patient records and side effect were graded according to CTC AE 3.0 in the source data.

Statistics: Chi-Square, Fisher's exact test, MANOVA and repeated measures ANOVA. Software: SPSS 18.

The study received approval from the local ethics comitee.

Results

We included 187 patients (185 female, 2 male) who received a total of 924 courses of chemotherapy with full eight-based dosing with either 6 courses of FEC-T (n = ,%) or TC (n = ,%). There were no differences accross BMI categories for age, gender, endocrine receptor expression, grading or her2-status.

Obese patients had more unplanned admission (p = 0.008), infections (grade 3-4, p = 0.005, all grades, p = 0.025) and diarrhoe (all grades, p = 0.033) compared to normal-weight patients. This was not the case for overweight patients (p = 0.063, 0.322, 0.199, 0.107, 0.065). Obese and overweight patients had more constipation than normal-weight patients (all grades, p = 0.025 and 0.006, respectively). There were no signficant differences across weight categories for neutropenic fever, delivered dose intensity, dose reduction and premature discontinuation of therapy.

Discussion

Obese and overweight patients can be treated with full dose intensity and do not suffer from excessive serious complications compared to normal-weight patients. However, due to partly increased toxicity seen in obese patients, adequate supportive therapy is of particular importance.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-12-12.