Incidence of de novo malignancy and all-cause mortality among heart transplant recipients

Background: Heart transplant recipients develop cancer at two-times the rate compared to the general population. However, the incidence and mortality rates and the adjusted association between cancer and mortality remains unclear. Methods: We estimated the incidence and mortality rates and the adjusted association between developing cancer (any, skin, hematologic, and solid tumor subtypes) and the all-cause mortality rates among adult heart transplant recipients from the Scientific Registry of Transplant Recipients from October 1, 1987, until June 28, 2020. Results: Among 51,597 adult heart transplant recipients, 13,191 (25.6%) were diagnosed with de novo malignancy throughout the follow-up period. The cumulative incidence cancer at years 1, 5, 10, and 20 was 3%, 16.4%, 32.8%, and 56.6%, respectively. Among those with cancer, the cumulative mortality was 17.5%, 42.3%, 65%, and 91% at years 1, 5, 10, and 20, respectively. The incidence rate of any de novo malignancy was 38.7 cases per 1000 person-years and the mortality rate (for those with cancer) was 115.2 cases per 1000 person- years. Compared to those without cancer, those with cancer had a higher adjusted mortality association [HR: 2.14 (2.07, 2.21)]. The strongest associations were estimated for pancreatic [10.63 (8.34, 13.54)], leukemia [8.06 (4.33, 15.00)], and esophagus [6.94 (5.43, 8.87)] malignancies. The association between de novo malignancies and mortality was higher in the earlier years of follow-up. Conclusion: Compared to not developing cancer, those with de novo malignancy have a 2-fold higher mortality rate, on average. The strength of the association varies by cancer subtype and by follow-up time.