380MO - Role of therapy in the development of second primary malignancies in ovarian cancer survivors: A SEER database analysis

Background

Ovarian cancer causes about 5% of female cancer deaths. As cancer therapy advances, the risk of developing a second primary malignancy is becoming increasingly important in planning patient's first cancer management. Our objective was to investigate the risk of occurrence of second primary malignancies (SPMs) in survivors of ovarian cancer after different treatment modalities.

Methods

This retrospective study used the Surveillance, Epidemiology and End Results (SEER) Program. Data from ovarian cancer patients diagnosed from 2000-2021 were extracted and used to calculate the multiple primaries standardized incidence ratio (MP-SIR) by SEER stat program. We then compared the Incidence Ratio of SPM after each treatment with the other.

Results

Out of 50,766 cases, 3,102 (6.1%) developed SPM. Of which 738 received adjuvant chemotherapy and 697 underwent surgeries only. For both treatments, significant excesses of risk of subsequent cancers were observed at the digestive system (SIR=1.2,1.4), vagina (SIR=5.03, 4.76), endocrine system (SIR=1.61, 2.04), thyroid gland (SIR=1.38, 2.1) and non-lymphocytic leukemia (SIR=3.13, 1.83) (p<0.05). Among patients whose treatment included surgery only, an increased risk of SPM compared to adjuvant chemotherapy patients was observed at: ureter (SIR=4.19) and female genital system (SIR=1.36), while a decreased risk of melanoma (SIR=0.69) (p<0.05). On the other hand, Adjuvant chemotherapy patients have a unique increased risk of subsequent pancreatic cancer (SIR=1.31), urinary bladder (SIR=1.38), leukemia (SIR=1.87) and peritoneal cancer (SIR=2.26) (p<0.05 for all), while a significant decrease in the risk of lung and bronchus cancer (SIR=0.7), liver and gallbladder cancer (SIR=0.58) was observed (p<0.05).

Conclusions

The risk for developing SPM differs across different treatment remedies, where pancreatic, urinary bladder, peritonial cancer and leukemia after adjuvant chemotherapy. Female Genital System cancers and ureter cancers were observed in patients who underwent surgeries only. This study may have important implications in developing a second primary malignancies site-specific screening post-diagnosis and treatment.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.