e11539 Background: We aimed to investigate the clinical and pathologic characteristics of patients with breast cancer (BC) who had a non-breast primary tumor and treated in our hospital. Methods: We identified BC patients with a second non-breast primary tumor retrospectively in our database. The tumors arising in a sequence by less than 2 months are accepted as synchronous malignancies. We noted clinical and pathological characteristics of breast tumors and analyzed the relapse patterns, the frequency and type of second non-breast primary tumors. Results: A total of 48 patients were identified. Median age was 59 years old. Thirty-four patients were postmenopausal, 41 tumors were IDC, 2 were DCIS only, eight were multiffocal. Two patients had metastatic BC at the time of diagnosis. Ninety-three (n: 26) % patients had breast conserving surgery, 2 had bilateral BC. Twenty-eight patients had node negative disease, 12 had node positive disease and 2 had micrometatatic nodal involvement. Fifty-four % were T1, 31% were T2 tumors. Histological grade was 3 for 14, 2 for 15 and 1 for 7 breast tumors. Forty patients had ER positive disease, 4 had ER/ PR negative disease, 2 tumors were triple negative and 6 tumors were Her-2 positive. Among non-breast second primary tumors; 29 arose after, 11 arose before the diagnosis of BC and 8 arose synchronously with BC. The most common non-breast second primary tumors were as follows: 15% lung cancer, 20% colorectal cancers, 13% ovarian cancer, 10% thyroid cancer, and 8% lymphoma/leukemia. With a median follow up of 76 months, there were 6 relapses; 4 of them were BC relapses. Among these 4 BC relapses, 3 patients had brain metastases and one patient had bone metastasis. There were 4 deaths; 2 were due to BC metastases, one was due to rectal cancer metastasis and the other was due to relapse of sarcoma. Conclusions: Most breast tumors were at early stage and were hormone sensitive. The most common second non-breast primary tumors arising after diagnosis of BC were colorectal, thyroid and lung cancers. The most common second non-breast tumor arising synchronously with BC was lung cancer and the most common second non-breast tumor arising before diagnosis of BC was lymphoma/leukemia.
The incidence of second primary tumors in thyroid cancer patients is increased, but not related to treatment of thyroid cancer