title: Toxicity and tolerability of adjuvant breast cancer chemotherapy in obese women.
abstract: The purpose of this study was to compare toxicity rates and types between obese and non-obese women during adjuvant chemotherapy for breast cancer, adjusting for regimen type and received dose. We conducted a retrospective cohort study of 537 women receiving chemotherapy, initially treated between 2007 and 2010 at two tertiary hospitals in Brisbane, Australia. Demographic, chemotherapy and toxicity data were extracted from patient charts and analyzed using multivariate logistic regression. Three hundred and seventy-four women were eligible for inclusion. Obese women (body mass index (BMI) > 30 kg/m(2); mean age 52.58 ± 9.49) were older than non-obese women (BMI ≤ 29.9 kg/m(2); mean age 50.19 ± 11.15, P = 0.05) and had more comorbidities (P < 0.01). After adjustment for potential confounders, obesity was not statistically related to chemotherapy-related admission risk (OR 1.27; 95 % CI 0.78-2.09) or febrile neutropenia risk (OR 0.56; 95% CI 0.28-1.21). However, obese women received chemotherapy with proportionally lower mean relative dose intensity than non-obese women (94 vs. 97% of reference dose, P = 0.03). Eighteen (15.8%) obese and zero non-obese women (P < 0.01) had their chemotherapy dose capped at an arbitrary body surface area. Compared with non-obese women, obese women receive different chemotherapy regimens and relatively lower chemotherapy doses. There was no significant evidence of increased toxicity among obese women with either full or adjusted chemotherapy doses. Full body surface areas-based dosing appears to be tolerated as well in obese as in lean women.
authors.affiliation: School of Medicine, University of Queensland, Herston Road, Herston, Brisbane, QLD, Australia, james.carroll@uqconnect.edu.au.
authors.forename: James P
authors.initials: JP
authors.lastname: Carroll
authors.forename: Melinda M
authors.initials: MM
authors.lastname: Protani
authors.forename: Linda
authors.initials: L
authors.lastname: Nguyen
authors.forename: Matthew E
authors.initials: ME
authors.lastname: Cheng
authors.forename: Mike
authors.initials: M
authors.lastname: Fay
authors.forename: Mohamed
authors.initials: M
authors.lastname: Saleem
authors.forename: Praga S
authors.initials: PS
authors.lastname: Pillay
authors.forename: Euan
authors.initials: E
authors.lastname: Walpole
authors.forename: Jennifer H
authors.initials: JH
authors.lastname: Martin
mesh_terms: D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000009:adverse effects; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects; D015992:Body Mass Index; D049628:Body Size; D001830:Body Surface Area; D001943:Breast Neoplasms / Q000150:complications* / Q000188:drug therapy*; D017024:Chemotherapy, Adjuvant / Q000009:adverse effects*; D015331:Cohort Studies; D003520:Cyclophosphamide / Q000009:adverse effects; D000077143:Docetaxel; D015251:Epirubicin / Q000009:adverse effects; D005260:Female; D005472:Fluorouracil / Q000009:adverse effects; D006801:Humans; D008875:Middle Aged; D015999:Multivariate Analysis; D009765:Obesity / Q000150:complications*; D016017:Odds Ratio; D012189:Retrospective Studies; D043823:Taxoids / Q000009:adverse effects
chemical_list: D000970:Antineoplastic Agents; D043823:Taxoids; D000077143:Docetaxel; D015251:Epirubicin; D003520:Cyclophosphamide; D005472:Fluorouracil