CLINICAL THYROIDOLOGY FOR THE PUBLIC
A publication of the American Thyroid Association
Thyroid cancer in survivors of Hodgkin’s lymphoma
ABBREVIATIONS & DEFINITIONS
Hodgkin’s lymphoma: a common cancer of the lymph glands that affects mainly younger people
Incidence: number of new cases of a condition per year.
History of radiation to the head/neck region is known to be a risk factor for the development of thyroid cancer since the thyroid is directly exposed to the radiation. Patients with Hodgkin’s lymphoma receive radiation to the neck region as part of their treatment. It is know that patient with Hodgkin’s lymphoma have an increased risk of developing thyroid nodules, presumably due to the radiation exposure. This study specifically examined the long-term risk of thyroid cancer in survivors of Hodgkin’s lymphoma.
THE FULL ARTICLE TITLE:
Michaelson EM et al. Thyroid malignancies in survivors of Hodgkin’s lymphom. Int J Radiation Oncol Biol Phys. 88(3): 636-641. 2014.
SUMMARY OF THE STUDY
This study examined the records of 1981 patients treated for Hodgkin’s lymphoma between 1969 and 2008 in a multi-institutional database located in Boston, Massachusetts. The majority of Hodgkin’s lymphoma survivors in this study had been treated with radiation after the age of 20. The investigators determined that the patients with Hodgkin’s lymphoma were 9.2 times more likely to develop thyroid cancer compared to the normal population and this risk increases over time. A total of 28 patients developed thyroid cancer over an average follow up time of 14.3 years, with the majority being papillary thyroid cancer. All but 2 of the 28 patients who developed thyroid cancer had received radiation therapy as part of their treatment for Hodgkin’s lymphoma. Female gender and radiation therapy before the age of 20 years were risk factors for developing thyroid cancer. Although thyroid cancer was more common in Hodgkin’s lymphoma patients compared to the normal population, the 10 year cumulative incidence was only 0.26%, suggesting that the overall incidence is low and that the vast majority of Hodgkin’s lymphoma survivors do not develop thyroid cancer.
WHAT ARE THE IMPLICATIONS OF THIS STUDY?
Although patients with a history of Hodgkin’s lymphoma are at increased risk of thyroid cancer, the overall incidence is low. This risk is highest in women who received radiation for their disease before the age of 20 years. Long term follow up and monitoring for thyroid cancer in these patients is required.
—Whitney Woodmansee MD
ATA THYROID BROCHURE LINKS
Thyroid cancer: http://www.thyroid.org/cancer-of-the-thyroid-gland