[Histopathological study on the safety of conservative breast surgery in terms of the degree of axillary dissection for breast cancer].

The subjects were 15 patients with primary mammary cancer who underwent radical mastectomy. Axillary dissection (level I, II and III) with an incision 7 cm below the axilla was performed. After radical mastectomy, the presence/absence of remaining lymph nodes and fatty tissue was determined. All operations were performed by the same surgeon. The number of lymph nodes dissected by means of subaxillary incision ranged from 10 to 32 (mean 20.4). The proportion of remaining lymph nodes found after radical mastectomy was 0/142 (0%) for level I, 0/113 (0%) for level II and 3/54 (5.6%) for level III. In the subclavian Halsted area, fatty tissue partially remained in 60.0% of the patients and more than half in 13.3%. It was shown that complete dissection of level III lymph nodes is difficult when this surgical technique is employed. Although fatty tissue did remain in some cases after level II dissecting, this technique presented hardly any problems in the case of level I and II dissection. Therefore, from the viewpoint of axillary dissection alone, the present technique can achieve results similar to those obtained by radical mastectomy, suggesting its applicability to mammary cancer at a relatively early stage.