Screening colonoscopy according to guidelines in long-term survivors of childhood cancer-results of a population-based study

Abstract

Purpose: To report on findings in screening colonoscopies in long-term survivors of childhood cancer treated with abdominopelvic irradiation (RT).

Methods: Screening colonoscopies were introduced at the Slovenian outpatient follow-up clinic in 2015, according to the Children's Oncology Group guidelines. In January 2019, 54 patients who received abdominopelvic irradiation for Hodgkin disease, Wilms tumour or dysgerminoma at the age of 0-16 between 1968 and 1995 were eligible for screening colonoscopy, and until December 2019, twenty-eight asymptomatic patients have undergone this examination.

Results: Patients were 1-16 (median 13) years old at cancer diagnosis and had colonoscopy 24-47 (median 36) years after diagnosis. They received abdominopelvic irradiation with the dose 16-46 (median 30) Gy. Adenomatous lesions were found in 18 patients (64%) and advanced adenomatous lesions in one-third. Patients who received abdominopelvic RT with a dose below 30 Gy had 75% incidence of adenomatous lesions and in those who received a dose of 30 Gy or more the incidence was 60%. Alkylating agents did not have impact on this incidence.

Conclusions: In this first population-based study of screening colonoscopies in asymptomatic survivors of childhood cancer, we provided new evidence for 64% incidence of adenomatous lesions after abdominopelvic RT with the dose above or below 30 Gy.

Implications for cancer survivors: Screening colonoscopies are of vital importance in patients treated with abdominal RT in childhood.

Keywords: Abdominal irradiation; Adenomatous lesions; Childhood cancer; Long-term survivors; Screening colonoscopy; Secondary colorectal cancer.