Endocrine Abstracts

Purpose: Radiation-induced anterior pituitary hormone deficiencie is the most common long-term complications of successful cancer treatment. The aim of our study was to analyze thyroid status in young adults after radiotherapy in childhood and their relationship with dose of radiotherapy.

Materials and methods: Thyroid function (TSH, free T4, free T3) and thyroid ultrasound were evaluated in 29 young adults with a history of radiotherapy for brain tumors (BT) and acute lymphoblastic leukemia (ALL) in childhood:

Group 1(lower irradiation dose cranial irradiation 18 Gy): 2 men and 10 women (median age 22.5 yrs (range 16–30)), 5.9±3.4 years after treatment for ALL. All patients received chemotherapy BFM-90.

Group 2(higher irradiation dose, craniospinal irradiation 55 Gy): 7 men and 10 women (median age 21.1 yrs (range 15–26), 4.4±2.1 years after treatment for brain tumors (BT). All patient received chemotherapy M-2000.

Results: One patient from group 1 had one thyroid nodule (FNA – follicular neoplasm, postoperative hystology of follicular adenoma). No patient had signs of hypothyroidism (mean TSH was 1.28 mME/ml (0.5–1.88), fT4 – 12.82 pmol/l (11.1–15.4), and fT3 – 10.03 pmol/l (7.1–15.0)).

Three patients (20%) from group 2 presented signs and symptoms of central hypothyroidism (fT4 5.2 (4.1–6.3)). They received substitution with L-thyroxine. Thyroid nodules were found in 2 patients (both colloid goiter after FNA). Mean TSH value (exept for three cases of central hypo) was 2.53 mME/ml (1.32–4.53), mean fT4 – 10.17 pmol/l (5.9–19.8), and mean fT3 – 6.22 pmol/l (4.1–13.0). The study is in progress.

Conclusions: These data indicate that treatment of cancer in childhood is associated with development of thyroid abnormality later during the life, and there is a possible link between exposure to higher total radiation dose and incidence of hypothyroidism.

Declaration of interest: I fully declare a conflict of interest. Details below:

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector