Objective To explore the etiology, clinical features, treatment and prognosis of multiple primary malignant neoplasms.

Methods The medical records of 120 patients with multiple primary malignant neoplasms in Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine were collected and analyzed retrospectively.

Results (1) Similar sex ratio; (2) The age of onset was 26-89 years old, with a median age of 58 years; (3) There were 116 cases of double primary malignant tumors, 2 cases of three primary malignant tumors, 1 case of four primary malignant tumors and 1 case of five primary malignant tumors; (4) There were 25 cases of simultaneous multiple primary malignant neoplasms, and 95 cases of metachronous multiple primary malignant neoplasms. The interval between onset was 6-444 months, and the median interval was 32 months; (5) The first malignant tumor was mostly in digestive system, the second primary malignant tumor was mostly in blood system; (6) The 3- and 5-year survival rates were 48.3% and 37.5%, respectively.

Conclusion Through clinical analysis, we could improve the understanding of multiple primary malignant neoplasms, guide the early clinical detection, diagnosis and treatment, so as to prolong the patient's life and improve the prognosis.