Prognostic Significance of Location of the Primary Tumor in Operable Breast Cancers

Background: The prognostic significance of the primary tumor site in breast cancers is not established with only a few studies having evaluated the issue.
Materials and Methods: The relevance of a primary tumor site with respect to systemic disease relapse was evaluated in 187 patients with breast cancer treated with primary surgery and adjuvant chemotherapy, in whom the location of primary tumor was classifiable in any one of the three sites, namely: outer, periareolar, and inner, quadrants. Data was obtained from prospectively maintained records of breast cancer patients treated at a single surgical unit in a tertiary care center.
Results: The three groups were comparable with regard to demographic, pathological tumor, and treatment characteristics. In the multivariate analysis, patients with inner and periareolar quadrant tumors had a higher hazard for systemic disease relapse, (2.53, 95% CI: 1.18-5.42; P = 0.02, and 2.73, 95% CI: 1.04-7.14; P = 0.04, respectively) as compared to outer quadrant tumors. The projected five-year survival estimates in Kaplan Meier were 87%, 61%, and 69%, respectively, for outer, periareolar, and inner quadrant. On further substratification the difference was particularly noted in high risk inner quadrant tumors: age ≤ 45, premenopausal patients, tumor size> 2 cms, positive nodes and intermediate or high grade histology, as also in patients treated with breast conservation and CMF, Cyclophosphamide, Methorexate, 5 Fluorouracil chemotherapy.
Conclusion: The location of the primary tumor influences survival in breast cancer with inferior outcome for tumors in inner and periareolar quadrants, especially in high risk groups and those treated with conservative approaches. The role of aggressive therapies merits investigation in these patients.

Keywords
Metastasis, risk factor, survival, systemic relapse, tumor site, quadrant