Multiple primary neoplasms involving the breast

Abstract

10786 Background: Multiple Primary Neoplasms (MPN) are being identified with increasing frequency in Breast cancer patients. We studied MPN involving Breast cancer as at least one primary for (1) incidence and (2) identifying. subsets with special features. Methods: 83 patients with MPN were identified among 3378 patients seen between January 1st 1999 and 31st December 2005. (2.15%). 40 of these had Breast primary (48.19%). which form the basis of the present report. One or both primaries were identified during this period. But in some cases with primaries in remote past, available documentation was accepted. Results: Breast cancer was the Index cancer 31/40 (77.50%)and second primary in 9/40 (22.50%). Among the index cancers, 4/31 cases (12.90%) were synchronous and 27/31 (87.10%) were metachronous. 100% of the second primary in breast group were metachronous. Breast-Breast MPN 15/40 (37.50%) and Breast-Non breast MPN 25/40 (62.50%). Mean ages for Breast-Breast MPN 47.33 years, Synchronous tumors 38.66 yrs, metachronous tumors 58.20 yrs, Breast-Non Breast MPN 55.44 yrs. Mortality for Breast-Breast MPN as a group was 73.33%, synchronous tumors (2/3) 66.67%, metachronous tumors (10/12) 83.33%, Breast-Non Breast MPN, metachronous tumors (13/24) 54.17%. When the interval between index and second primary was studied, the Breast-Breast MPN mortality was (7/9) 77.78% for 2 yrs or less duration, (3/3) 100% for more than 2yrs. For Breast-NonBreast MPN, mortality was (6/9) 66.67% for duration of 2 yrs or less and (7/15) 46.67% for more than 2 yrs. The common malignancies associated in the index Breast cancer group were from Ovary (6),Thyroid (2),pancreas (2), Hematologic neoplasms (3) Upper Aero Digestive Tract (2). The second primary Breast cancer group had primaries in ovary (2), colon (2), hematologic (3) neoplasms. Conclusions: Breast-Breast MPN are seen in younger patients with higher mortality than Breast-Non Breast MPN. In the Breast-Non Breast MPN group, longer interval between the primaries is associated with lower mortality. There were no major differences between the Index Breast cancer group and Breast Second Primary group. Mortality appeared to be determined by the nature of the Non Breast Primary. No significant financial relationships to disclose.