Prefectural Survey on Immune Checkpoint Inhibitor-Associated Myocarditis at the Start of the Basic Plan to Promote Cancer Control Programs - Phase 4.

Background: In 2023, collaboration between cardiologists and oncologists was recommended as part of Japan's Basic Plan to Promote Disease Control Programs for both cancer and cardiovascular diseases. This study explores the extent of this collaboration in Niigata Prefecture.

Methods And Results: Self-administered questionnaires about immune checkpoint inhibitor-associated myocarditis (ICIAM) and anthracycline-related cardiomyopathy (ARCM) were distributed to all cardiologists and leading oncologists in hospitals across the Prefecture, of whom 124 cardiologists and 41 oncologists across 29 hospitals responded. Clinical experience with ICIAM was reported by 31.8% of cardiologists and 24.4% of leading oncologists, significantly lower than experience with ARCM (80.0% of cardiologists, P<0.001, and 58.5% of leading oncologists, P=0.009, respectively). Senior cardiologists reported less experience with ICIAM compared with their young counterparts (18.6% vs. 38.5%, P=0.018). Of the 20 hospitals providing immunotherapy, 12 (60%) reported "no consultation" between the cardiology and oncology departments, and only 5 hospitals (25%) had matching answers for consultation after ICIAM onset between these departments. Conversely, only 4 hospitals (20%) answered "no consultation", and 12 hospitals (60%) had matching answers, for interdepartmental consultation before or after ARCM onset.

Conclusions: Compared with ARCM, cardiologists and oncologists had less experience, fewer organized measures in place, and increased interdepartmental collaboration vulnerability with ICIAM. Collaboration between cardiologists and oncologists should be promoted in hospitals.