Lymphedema of the arm is a serious consequence of breast carcinoma treatment. Postmastectomy lymphedema of the upper limb usually is related to certain risk factors such as axillary surgery, radiotherapy, obesity, venous outflow obstruction, delayed wound healing, and infection. The objective of the current study was to identify the risk factors for secondary lymphedema after breast carcinoma treatment.

A total of 1278 breast carcinoma patients, all of whom were residents of Florence area, Italy at the time of diagnosis and who were operated on by the same surgeon between 1989 and 1997, were included in the current analysis. The circumference of the upper arm was measured and lymphedema was defined as being present when an increase of > 5% of the sum differences between the two arms was found. The observed cumulative probability of lymphedema occurrence was estimated using the Kaplan–Meier method. The Cox proportional hazards models were fitted to assess the relative excess risk of lymphedema and to check for confusing factors. All patients with lymphedema who were living in the Florence area were referred to a specialist for treatment.

Two hundred three cases of lymphedema of the ipsilateral arm were found (15.9%). The right arm was affected in 44.5% of the cases and the left arm in 55.5%. The risk of developing late lymphedema was found to be significantly related to a pathologic T2 classification (hazards ratio [HR] = 1.44; 95% confidence interval [95% CI], 1.06–1.94) and postoperative radiotherapy (HR = 1.35; 95%CI, 1.00–1.83). Patients who had > 30 lymph nodes removed were found to have a borderline increased risk of lymphedema (HR = 1.64; 95% CI, 0.99–2.74). Multivariate analysis identified postoperative radiotherapy (HR = 1.38; 95% CI, 1.02–1.86) and the number of lymph nodes removed (HR = 1.29; 95% CI, 1.04–1.59) to be independent predictors of lymphedema.

The results of the current study demonstrated that the risk of lymphedema was correlated with the use of postoperative radiotherapy and the number of lymph nodes removed. Cancer 2001;92:1783–7. © 2001 American Cancer Society.