Risk assessment for potential radiation-induced cancer after lung and bone marrow exposure during interventional cardiology procedures

Interventional cardiology procedures (ICPs), while providing important benefits to patients, also contribute to their radiation exposure, in particular for the organs surrounding the heart. This paper addresses the issue of radiation exposure to the lung and bone marrow related to coronary interventions in terms of organ doses for coronary angiography (CA) and percutaneous transluminal coronary angioplasty (PTCA), and risk assessment of potential radiation-induced cancer. Dosimetric information on 2095 ICPs from French patients was collected. The median lung dose for CA alone was 34 mGy for men and 22 mGy for women and the median bone marrow dose was 8 mGy and 4 mGy, respectively; doses were slightly higher for CA and ad hoc PTCA and nearly twice as high for CA and elective PTCA. Based on the French national mortality registry and Biological Effects of Ionising Radiation VII models, spontaneous and radiation-induced lung cancers and leukaemia were estimated. For men and women aged at least 60 years old at the first ICP, excess risk of potentially fatal cancers attributable to radiation ranged from 0.4% to 4%. This study provides evidence of the potential risk of radiation-induced cancer after an ICP. The limitations of such calculations are due to the difficulty of taking into account patients' possibly shorter life expectancy than in the general population, linked to their comorbidities and coronary disease. Nevertheless, risk estimates can be used to illustrate the beneficial role of optimisation of doses delivered to the patient.