Radiological follow-up in patients with resected pulmonary carcinoids: Should we reduce radiation exposure?

Introduction: After primary resection of pulmonary carcinoids, the recurrence rate is low (approximately 10 %). However, long-term radiological follow-up is generally recommended due to the risk of late recurrence. This must be weighed against risk of radiation-induced cancer, particularly in young patients. Methods: The frequency and modality of radiological follow-up according to the ENETS, ESMO, and CommNETsNANETS guidelines were assessed. Cumulative radiation exposure per guideline and subsequent increased lifetime cancer risk were estimated using sex- and age-dependent risk factors. Data from the Netherlands Cancer Registry (2003-2012) of adults with resected pulmonary carcinoids were used as a reference. Results: Of 706 reference patients, 32 (4.5 %) were 18-30 years (y). After median follow-up of 127 months, none of the patients aged 18-30y at diagnosis developed recurrence. For these patients, the additional radiation exposure at the age of 40y due to follow-up ranges from 140-308 mSv following ENETS and 35-42 mSv following ESMO guidelines. The additional risk of death due to carcinogenic effects ranged from 0.7 % (male 30y) to 3.1 % (female 18y) following ENETS and 0.2 % (male) to 0.4 % (female) following ESMO guidelines. Conclusions: Individualised, less extensive follow-up for young patients with resected carcinoids and a low risk of recurrence are worth exploring to decrease radiation exposure and the corresponding risk of cancer induction. The use of predictive biomarkers to personalise follow-up is warranted.