There are several factors for metastasis in breast cancer, such as tumor size (T) and lymph node involvement (N). In this study was investigated the association of T and N with metastasis in breast cancer patients treated in the Oncology Sector of a public Hospital of Minas Gerais.
Observational and retrospective study. A total of 1671 medical records of women with breast cancer treated in the period of 1981-2013 were analyzed, of which 797 were excluded for lack of pathologic data or by being diagnosed in advanced stage. Fisher’s exact test or χ2 were performed.
As expected, the positivity of lymph node metastasis increased with tumor size: of the Tis patients, 5.55% were N + (3.7% N1, 1.85 N2); of T1, 25.29% were N + (21.01% N1, 4.28% N2); of T2, 51.45% were N + (37.21% N1; 9.88% N2; 4.36% N3); of T3, 77.05% were N + (55.74% N1; 18.03% N2; 3.28% N3); and of T4, 80% were N + (48.57% N1; 17.14% N2; 14.29% N3). When analyzed by T, decreased odds of metastasis in Tis (OR = 0.3435; p = 0.0197) and T1 (OR = 0.3805; p < 0.0001) were observed, while increased odds in T2 (OR = 1.469; p = 0.0364), T3 (OR = 2.114; p = 0.0081) and T4 (OR = 4.222; p < 0.0001). When analyzed by N, decreased odds of metastasis in N0 (OR = 0.1587; p < 0.0001) was observed and increased odds in N1 (OR = 2.56; p < 0.0001), N2 (OR = 3.703; p < 0.0001) and N3 (OR = 4.328; p = 0.0002). Overall, N+ had an increased odd of metastasis when compared with N- (OR = 6.321; p < 0.0001) patients. Increased odds only in T1N + (OR = 9.49; p < 0.0001) and T2N + (OR = 3.557; p < 0.0001) was observed when compared with their N- counterparts. Moreover, a borderline increase in the odds (OR = 3.667; p = 0.0533) was observed in T1N2 compared with in T1N1, but not in T2 (p = 0.9190) nor T3 (p = 0.4639) patients.
Lymph node involvement (N) is a greater risk factor for metastasis than tumor size (T). Adjuvant therapy is based on T, N and molecular subtype. In the minimal axillary approach by sentinel lymph node (SL) the pathologic analysis of this unique sample, and maybe including two other lymph nodes, have a great prognostic weight, mainly in early stage. These data corroborate the lack of necessity in dividing, as formerly, between the 12 or more dissected lymph nodes in a clinically negative axilla.
Clinical trial identification
Legal entity responsible for the study
Grupo Luta Pela Vida.
Grupo Luta Pela Vida.
All authors have declared no conflicts of interest.