Hastalardaki en sık ilk primer tümör jinekolojik tümörler (10 hasta, %26,3) iken, en sık ikinci primer tümör meme kanseri (7 hasta, %18,4) idi. En sık tümör birliktelikleri ise sırasıyla: jinekolojik tümörler-meme kanseri (5 hasta, %13,1), jinekolojik-jinekolojik tümörler (3 hasta, %7,9), sarkom-meme kanseri (3 hasta, %7,9), baş boyun tümörleri-akciğer kanseri (3 hasta, %7,9), üriner sistem-üriner sistem tümörleri (3 hasta, %7,9) şeklindeydi. Sonuçlar. Sonuçlarımız literatürr ile uyumludur. Kanser tanısı almış hastalar, olası ikinci kanserler, koruyucu önlemler ve tarama hakkında bilgilendirilmeli ve şüpheli lezyonlarda biyopsiden kaçınılmamalıdır.Anahtar sözcükler: Kanser, ikinci primer neoplasm, multipl neoplaziler, metakron, senkron Abstract Aim. Developments in cancer treatment and longer anticipated life period have brought out late side effects related to therapy and development of a second cancer. Multiple primary malignant neoplasms (MPMN) are described as pathological diagnosis of two or more independent primary reportable neoplasms in an individual. In this study we aimed to investigate demographic, pathological and clinical features of patients with multiple primary cancers in our center. Method. From January 2007 to January 2012, medical files of totally 3108 cancer patients were retrospectively screened. Results. Thirty-eight (1.2%) of 3108 cancer patients followed-up at our centre were diagnosed as MPMN. Of these patients, 21 (55.3%) was female, and 17 (45%) was male. While 37 patients were found to have two different primary malignant neoplasms, only one patient had three different primary cancers. The median age at the initial time of second primary cancer was 60 years (32-76). Patients with MPMN were diagnosed as synchronous neoplasm in six patients (16%) and as metachronous neoplasm in thirty-two (84%) patients. The median interval between the first and second cancers was 40 months (0-372). The most common primary tumor was gynecological cancers (n=10; 26%) and the most common secondary cancer was breast cancer (n=7; 18%). The most common cancer couplings were gynecological-breast cancer (n=5; 13%), gynecological-gynecological cancer (n=3; 8%), sarcoma-breast cancer (n=3; 8%), head and neck-lung cancer (n=3; 8%), and urinary-urinary system cancer (n=3; %8), respectively. Conclusion. Our results comply with the literature. Patients with cancer should be informed by physicians about development of secondary neoplasm, cancer prevention and screening. Clinicians should not hesitate from biopsy in suspected lesions.