Risk of malignancy in adult patients with congenital heart disease: a clinical practice review.

This paper presents case studies of adult patients with congenital heart disease (CHD) who developed cancer and also discusses relevant epidemiological studies, risk factors, and reports on early detection. Herein, we describe three cases: a 63-year-old man with an atrial septal defect and multiple myeloma; a 48-year-old man with tetralogy of Fallot and colorectal cancer; and a 25-year-old man with Fontan circulation and hepatocellular carcinoma (HCC). Previous studies have found that the incidence of cancer in adult patients with CHD is higher than that in the general population. The management of adult patients with CHD complicated by cancer requires careful attention because cancer treatment alone can affect the survival prognosis and quality of life, as well as the pathophysiology and treatment of underlying heart disease. Apart from known risk factors in the non-CHD population, specific risk factors have been reported, such as genetic abnormalities, low-dose ionizing radiation exposure, early thymectomy, Fontan-associated liver disease, and hypoxia. Encouraging patients to participate in cancer screening and avoid known risk factors is essential in daily practice for the early diagnosis and prevention of cancer. It is also important to be vigilant for initial signs that are indicative of cancer as well as avoidable risk factors.