Validation of the EPIPHANY index for predicting risk of serious complications in cancer patients with incidental pulmonary embolism

Purpose The EPIPHANY index was developed to classify cancer associated pulmonary embolism (PE) into different risk categories using decision tree modeling. In this study, we tried to externally validate this index in a distinct group of patients solely composed of incidental PE (IPE). Methods A retrospective study of patients diagnosed with IPE in two Emergency Departments in the USA and South Korea from 2013 to 2014 was performed. The primary outcome was the occurrence of a serious medical complication within 15 days of presentation to ED. Thirty-day complication was the secondary outcome. Cumulative hazard curves for each prognostic category were drawn to show the change in hazards over time. Results A total of 258 patients with IPE were included (193 from MD Anderson Cancer Center and 65 from Asan Medical Center). Serious complication within 15 days occurred in 23 (8.9%) patients. The risk of overall 15-day and 30-day serious complications increased with each category (low, intermediate, and high risk: 3.4, 8.9, and 23.8%, P = 0.033; 6.9, 9.5, and 33.3%, P = 0.011). Cumulative hazard curves for each prognostic category were drawn and the survival functions factored by prognostic categories were significantly different over 15 days ( P = 0.015) and 30 days ( P = 0.001). Conclusions Our study suggests the EPIPHANY index could be a useful adjunct tool in risk stratification of cancer patients with IPE.