RISK OF ARM LYMPHEDEMA WITH TAXANE AND ANTHRACYCLINE USE AMONG PATIENTS WITH BREAST CANCER

Purpose: In the United States, over 5 million women suffer from arm lymphedema as a complication of breast cancer treatment.  Chemotherapy regimens for breast cancer often contain anthracyclines as a central component, and these medications have been associated with increased incidence and severity of arm lymphedema. Taxane-based chemotherapy regimens for breast cancer have become increasingly more common; however the risk of arm lymphedema in comparison to anthracyclines has not been assessed yet.  The purpose of this study was to compare the rate of arm lymphedema among breast cancer patients treated with taxane- versus anthracycline- based chemotherapy regimens.

Method: A cohort study design was used to compare the risk of arm lymphedema among breast cancer patients exposed to taxanes with those exposed to anthracyclines within 90 days of their first breast cancer diagnosis. Characteristics of taxane and anthracycline users were compared using t-tests and chi-squared tests. A Cox proportional hazard model was used to estimate the hazard ratio for arm lymphedema among taxane users versus anthracycline users after adjusting for potential confounders. We controlled for age, gender, patient region, index year, hypertension, renal failure, congestive heart failure, stroke, liver failure, vascular disease, arrhythmia, type of surgical dissection (sentinel/auxiliary), radiation, mastectomy performed, use of corticosteroids, and use of antihypertensive medications in the Cox model.

Result: A cohort of 1,750 breast cancer patients in the IMS Lifelink Plus (2006-2013) database met our inclusion-exclusion criteria, which included 1,215 anthracycline (2052.57 person-years) and 625 taxane users (1412.67 person-years). The rate of arm lymphedema was significantly lower among taxane userscompared to anthracycline users in the unadjusted analysis (Hazard ratio = 0.784[95% C.I.=0.625-0.948]). After adjusting for potential confounders, the rate of arm lymphedema was still significantly lower among the taxane users compared to anthracycline users (Hazard ratio = 0.783[95% C.I.=0.618-0.993]).

Conclusion: The rate of arm lymphedema may be decreased by using taxanes instead of anthracyclines as a treatment for breast cancer. However, interpretation of these findings should be considered in light of moderate sample size and the inadequacy of claims data to control for all the unobserved potential confounders.