Role of increased arterial inflow in arm edema after modified radical mastectomy.

Chronic arm edema is a common finding after modified radical mastectomy and its pathophysiology is unclear. In a prospective study the value of increased arterial inflow and venous abnormalities after mastectomy was evaluated. Arterial and venous blood flow in axillary vessels of 39 patients with arm swelling and 16 patients without swelling were investigated by Doppler ultrasound. In patients with arm edema the arterial flow on the surgical treated side was 689.73+/-44.6 (mean+/-sem) ml/min and 427.73+/-30.8 ml/min on the contralateral side (p<0.05). In those without swelling the flow was 447.75+/-37.8 ml/min on the treated side and 354.95+/-28.7 ml/min on the contralateral side (p>0.05). The difference between arterial flow measurements on the treated sides of the patients with and without arm swelling was statistically significant. There was no significant difference between the measurements on the contralateral sides of both groups. Venous abnormalities were not detected in both groups of patients. We, therefore, conclude that modified radical mastectomy causes increased inflow in ipsilateral arm and it may play an important role in the etiology of arm swelling in breast cancer patients.