Thyroid carcinoma after treatment for malignancies in childhood and adolescence: From diagnosis through follow-up

With improvements in the survival rates after childhood cancer, many clinicians have turned their attention to reporting on late effects, and how they might be prevented or treated. In childhood the thyroid gland is especially vulnerable to the carcinogenic action of ionizing radiation. This retrospective study focused on secondary thyroid cancers seen at our institution over more than 30 years (between 1980 and 2012) in patients treated for other malignancies in pediatric age. 36 patients were identified. In most cases, the primary cancer had been Hodgkin disease, and all the patients had been administered radiotherapy for their first malignancy. The secondary thyroid cancers were treated with total thyroidectomy in 27 cases (six with lymphadenectomy), and hemithyroidectomy in nine (one with lymphadenectomy). 12 Patients were also given radiometabolic therapy. All but two had TSH suppression therapy. The histological diagnoses were: 31 papillary and five follicular carcinomas. At 5 and 10 years, the OS was 100 and 95%, respectively, and the PFS was 96 and 83%. None of the patients died of their thyroid disease. Nodal involvement at onset was the only factor correlating with recurrence. Surgical sequelae only occurred in patients who underwent total thyroidectomy. Survival in these patients did not depend on the extent of surgery on the thyroid parenchyma. Our data confirm a good prognosis for secondary thyroid cancer, prompting us to encourage a minimalist approach to the treatment of these particular patients wherever possible.