Concurrence of ovarian cancer and dermatomyositis: a propensity score analysis

OBJECTIVE: To analyze the clinical characteristics, prognosis and parallel clinical course of ovarian cancer (OC) and dermatomyositis (DM). METHODS: The medical records of 23 consecutive patients who were diagnosed with OC and DM and were treated at Peking Union Medical College Hospital (PUMCH) between 2002 and 2017 were reviewed. Propensity score matching method was used to match control group (OC patients without DM) at a ratio of 1:5. The correlation between OC and DM was measured using the Pearson correlation scatter plot and Pearson's r. Kaplan-Meier survival analysis and Cox proportional hazard regression analysis were performed to evaluate the prognostic factors. RESULTS: After matching, 23 patients who have the concurrence of OC and DM (DM group) and 115 patients diagnosed with OC alone (No DM group) were included. The 5-year overall survival rates (71.6% vs. 51.8%, p=0.020) and 5-year progression-free survival (30.5% vs. 0%, p=0.018) were poorer in DM group. Correlation between serum cancer antigen 125 (CA 125) and creatine kinase (CK) level was observed in 12 patients. The time between OC and DM diagnosis is significant through univariable analysis (p=0.021) but not in multivariable analysis in patients who have the concurrence of OC and DM. CONCLUSION: The concurrence of OC and DM as a paraneoplastic syndrome is rare and has a poor prognosis. The risk for patients diagnosed with DM is highest within 3 years before or after OC diagnosis. A correlation and a parallel clinical course exist between these 2 diseases.