Risk and Prognosis of Second Primary Cancers among Ovarian Cancer Patients, Based on SEER Database.

The purposes of the present study were to elucidate the risk and prognostic effect of second primary cancers (SPCs) development, as well as the factors influencing the prognosis of OC patients with SPCs. A statistically significant increase in SPCs risk was observed among OC patients during 2004-2015. The independent factors were used to construct the SPCs-prediction nomogram and the OS-prediction nomogram. Both nomogram were subjected to internal validation and performed well. OC patients with SPCs have a better prognosis than patients without SPCs. Propensity score matching (PSM) was applied to reduce confounding.