BACKGROUND. Lymphedema of the arm is a serious consequence of breast carcin
oma treatment. Postmastectomy lymphedema of the upper limb usually is relat
ed to certain risk factors such as axillary surgery, radiotherapy, obesity,
venous outflow obstruction, delayed wound healing, and infection. The obje
ctive of the current study was to identify the risk factors for secondary l
ymphedema after breast carcinoma treatment.
METHODS. A total of 1278 breast carcinoma patients, all of whom were reside
nts 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 wa
s defined as being present when an increase of > 5% of the sum differences
between the two arms was found. The observed cumulative probability of lymp
hedema occurrence was estimated using the Kaplan-Meier method. The Cox prop
ortional hazards models were fitted to assess the relative excess risk of l
ymphedema and to check for confusing factors. All patients with lymphedema
who were living in the Florence area were referred to a specialist for trea
tment.
RESULTS. 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 lef
t arm in 55.5%. The risk of developing late lymphedema was found to be sign
ificantly related to a pathologic T2 classification (hazards ratio [HR] = 1
.44; 95% confidence interval [95% CI], 1.06-1.94) and postoperative radioth
erapy (HR = 1.35; 95%CI, 1.00-1.83). Patients who had > 30 lymph nodes remo
ved were found to have a borderline increased risk of lymphedema (HR = 1.64
; 95% CI, 0.99-2.74). Multivariate analysis identified postoperative radiot
herapy (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.
CONCLUSIONS, The results of the current study demonstrated that the risk of
lymphedema was correlated with the use of postoperative radiotherapy and t
he number of lymph nodes removed. (C) 2001 American Cancer Society.