In order to clarify the factors that mainly influence arm morbidity following treatment of breast cancer with the full axillary dissection protocol, we evaluated, in a model of multiple regression analysis, parameters such as the type of breast surgery, adjuvant radiotherapy, time of irradiation, age, number of dissected nodes and axillary nodal status. A total of 104 women were studied. Late arm edema was observed in 17% of the patients and was more frequent when (1) irradiation was given immediately after the operation than if it was given 6 months later (p = 0.009) and (2) the number of removed nodes exceeded 40 (p = 0.037). Upper limb pain was reported by 16% of the patients and was reported more frequently from patients over 60 years of age (p = 0.036), as well as from patients who underwent modified radical mastectomy (p = 0.044) and those in whom 30–40 nodes were dissected (p = 0.025). Shoulder joint mobility was impaired in 17% of the patients, and it was not affected by any of the examined factors. It seems that conservative breast surgery or adjuvant breast radiotherapy 6 months after the operation might reduce independently the likelihood of arm morbidity by 25%.