Purpose: The incidence of multiple primary malignant neoplasms (MPMN) has dramatically increased. The purpose of this retrospective study was to present the 12-year experience at a University Hospital in patients with MPMN and to investigate the role of genetic factors in their pathogenesis.
Methods: The medical records of 7516 cancer patients, treated in our Institution from 2000 to 2012, were reviewed. Diagnosis of MPMN was based on the Warren and Gates' criteria.
Results: Among 7516 patients, 39 (0.5%) (10 men, mean age 70.0±6.98 years, and 29 women, mean age 64.7±8.24 years) presented with MPMN. Eighty-two percent of them developed 2 primary malignant neoplasms (PMNs), whereas 3 PMNs were developed in 7 patients. Breast cancer was the most common cancer type diagnosed among female patients (59%); 14 and 3 had 2 and 3 PMNs, respectively. Eight had a family history of breast cancer while in 3 genetic testing revealed mutations in BRCA1 and BRCA2 genes. The second most common type of malignancy was colorectal cancer (24%); 5 developed 2 PMNs, whereas 2 developed 3 PMNs. Five patients had a family history of colorectal cancer. Colon cancer was the most frequent neoplasm among male patients (50%; 3 developed 2 and 2 3 PMNs. In 2 patients the family history was positive for colorectal cancer.
Conclusions: Although many factors may contribute to MPMN development, positive family history and inherent mutations significantly predispose to MPMN appearance. Thus, management of MPMN patients should be based on a detailed family history and genetic testing.