Chemoradiation and hypothyroidism in patients with Hodgkin Lymphoma.

This study investigated the development of hypothyroidism in patients with Hodgkin lymphoma after chemoradiation therapy. Patients were more likely to develop hypothyroidism after intensity modulated radiation therapy than after 3-dimensional conformal radiation therapy.

Patients with Hodgkin lymphoma (HL) are commonly treated with chemoradiation. Chemoradiation is a combination of radiation and chemotherapy. Two types of chemoradiation are intensity modulated radiation therapy (IMRT) and 3-dimensional (3D) conformal radiation therapy (CRT). IMRT involves using varying strengths of radiation to kill tumor cells. 3D-CRT involves creating a 3D image of the tumor. This image is used to guide the delivery of strong radiation to kill tumor cells.

Hypothyroidism may develop following chemoradiation therapy. Hypothyroidism means that the thyroid does not produce enough thyroid hormone. As a result the patient may feel tired, depressed or gain weight. Therefore, it is important to measure these thyroid hormones in patients with HL treated by chemoradiation.

One hundred and forty patients with HL were included in this study. Ninety patients had received IMRT. Fifty patients had received 3D-CRT.  These patients were evaluated between 2009 and 2014.  The development of hypothyroidism was monitored.  

Patients who received IMRT were slightly more likely to develop hypothyroidism. After 3 years, 56.1% of patients treated with 3D-CRT had not developed hypothyroidism. Forty percent of patients treated with IMRT did not develop hypothyroidism.  Thyroid exposure to high-dose radiation strongly predicted hypothyroidism development. Also, the greater the volume of the thyroid which was spared from radiation exposure, the less likely the patient was to develop hypothyroidism.

The main finding was that patients who were treated with IMRT were slightly more likely to develop hypothyroidism than those treated with 3D-CRT

This study only included a small group of patients. Therefore, the results may not represent a larger population of patients with HL.

If you have questions about treatments for HL, please ask your doctor.