Risk factors for lymphedema after breast cancer treatment.
BACKGROUND
As cancer treatments evolve, it is important to reevaluate their effect on lymphedema risk in breast cancer survivors.


METHODS
A population-based random sample of 631 women from metropolitan Philadelphia, Pennsylvania, diagnosed with incident breast cancer in 1999 to 2001, was followed for 5 years. Risk factor information was obtained by questionnaire and medical record review. Lymphedema was assessed with a validated questionnaire. Using Cox proportional hazards models, we estimated the relative incidence rates [hazard ratios (HR)] of lymphedema with standard adjusted multivariable analyses ignoring interactions, followed by models including clinically plausible treatment interactions.


RESULTS
Compared with no lymph node surgery, adjusted HRs for lymphedema were increased following axillary lymph node dissection [ALND; HR, 2.61; 95% confidence interval (95% CI), 1.77-3.84] but not sentinel lymph node biopsy (SLNB; HR, 1.04; 95% CI, 0.58-1.88). Risk was not increased following irradiation [breast/chest wall only: HR, 1.18 (95% CI, 0.80-1.73); breast/chest wall plus supraclavicular field (+/- full axilla): HR, 0.86 (95% CI, 0.48-1.54)]. Eighty-one percent of chemotherapy was anthracycline based. The HR for anthracycline chemotherapy versus no chemotherapy was 1.46 (95% CI, 1.04-2.04), persisting after stratifying on stage at diagnosis or number of positive nodes. Treatment combinations involving ALND or chemotherapy resulted in approximately 4- to 5-fold increases in HRs for lymphedema [e.g., HR of 4.16 (95% CI, 1.32-12.45) for SLNB/chemotherapy/no radiation] compared with no treatment.


CONCLUSIONS
With standard multivariable analyses, ALND and chemotherapy increased lymphedema risk whereas radiation therapy and SLNB did not. However, risk varied by combinations of exposures.


CONCLUSIONS
Treatment patterns should be considered when counseling and monitoring patients for lymphedema.
Norman
Sandra A
SA
Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania, Philadelphia, PA 19104-6021, USA. snorman@mail.med.upenn.edu
Localio
A Russell
AR
Kallan
Michael J
MJ
Weber
Anita L
AL
Torpey
Heather A Simoes
HA
Potashnik
Sheryl L
SL
Miller
Linda T
LT
Fox
Kevin R
KR
DeMichele
Angela
A
Solin
Lawrence J
LJ
D000368:Aged; D000970:Antineoplastic Agents / Q000009:adverse effects* / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000628:therapy*; D003131:Combined Modality Therapy / Q000009:adverse effects; D005260:Female; D006801:Humans; D008197:Lymph Node Excision / Q000009:adverse effects*; D008209:Lymphedema / Q000453:epidemiology* / Q000209:etiology*; D008875:Middle Aged; D016016:Proportional Hazards Models; D011878:Radiotherapy / Q000009:adverse effects*; D012307:Risk Factors; D021701:Sentinel Lymph Node Biopsy / Q000009:adverse effects; D011795:Surveys and Questionnaires
D000970:Antineoplastic Agents