Clinical and Pathological Evaluation of 102 Patients with Internal Mammary Node Metastases in a Single Breast Unit

Abstract

INTRODUCTION: Although incidence of internal mammary node (IMN) recurrence is only 0.1%, and almost all of these patients have systemic disease, it has an important prognostic value when both axillary and IMN are positive. But routine sentinel node (SN) biopsy of IMN is not standard practice and warrants further investigation of patients who may benefit of this procedure. METHODS: 561 patients with invasive carcinomas who underwent to Patey’s mastectomy (between 1987 and 2004) and skin-sparing mastectomy (after 2004) between 1987 and 2012 in HNSG Breast Unit in Curitiba (Brazil) were included in this study, and underwent to a routine IMN biopsy in the second and third intercostal space, together with complete axillary dissection in 3 Berg’s levels. After 1997 only patients with positive SN underwent to this procedure. RESULTS: 102 patients (18%) in this group had positive IMN. The age ranged from 28 to 85 years, with a median of 52 (sd=12) years. 94 (92%) were invasive ductal carcinomas, 6 (6%) invasive lobular carcinomas, 1 (1%) mucinous invasive carcinoma, and 1 (1%) medullary carcinoma. Most of the tumors were T2 (57%) and T3 (21%), and only 3% were T1. Lymphovascular invasion was found in 99 (97%) in this group. 9 (9%) patients had no positive axillary nodes, and for those with both axillary and IMN positive, median of compromised nodes was 9 (sd=12), 22% of IMN positive had 1-3 compromised axillary nodes, 48% had 4-10, and 31% had more than 10. In the follow-up, 57 (56%) died with disease, 22 (22%) were alive without disease, 5 (5%) were alive with disease, and 22 (22%) lost follow-up. CONCLUSIONS: IMN was positive in more advanced and aggressive tumors. Implication of these results to IMN adjuvant radiotherapy needs further investigation.