Biomaterial Database

Hypothyroidism after external radiotherapy for head and neck cancer. 1997

R Tell, and H Sjödin, and G Lundell, and F Lewin, and R Lewensohn

Department of Oncology, Radiumhemmet, Karolinska Hospital, Stockholm, Sweden.

OBJECTIVE To study the development of thyroid hypofunction in patients with head and neck cancers admitted for external radiotherapy. METHODS Between November 1990 and July 1996, thyroid function was measured in 264 consecutive patients, where the entire thyroid gland or part of it was included in the target volume. The time to development of hypothyroidism (HT) was calculated from the start of the radiotherapy. RESULTS The median follow-up period was 19 months. Seventeen patients (6%) developed elevated serum thyroid-stimulating hormone levels with depressed (free) thyroxine levels (i.e., clinical HT). Elevated serum thyroid-stimulating hormone level with normal (free) thyroxine levels (i.e., chemical HT) developed in 57 (22%). The median time to clinical HT was 15 months (range: 7 to 32). The median time to chemical HT was also 15 months (range: 2 to 28). The actuarial risk of developing clinical or chemical HT 3 years after treatment was 15 and 40%, respectively. The incidence of chemical HT was significantly higher (p = 0.041) when the whole thyroid was included in the target volume compared to patients where only part of the thyroid was irradiated. The same trend was seen as regards clinical HT (p = 0.063). For those 20 patients who underwent laryngectomy, there was an increased risk of both chemical and clinical HT (p = 0.011 and 0.019, respectively). Increasing age was associated with an increased risk of chemical HT (p = 0.001), but not of clinical HT (p = 0.553). Sex, tumor site, radiation dose, and combination of radiotherapy and chemotherapy were not significant factors for thyroid hypofunction. CONCLUSIONS Depressed thyroid function is common after external radiotherapy for cancers of the head and neck. Routine testing for possible thyroid hypofunction should be included in the follow-up procedures, even many years after end of radiotherapy.

UI	MeSH Term	Description	Entries
D007037	Hypothyroidism	A syndrome that results from abnormally low secretion of THYROID HORMONES from the THYROID GLAND, leading to a decrease in BASAL METABOLIC RATE. In its most severe form, there is accumulation of MUCOPOLYSACCHARIDES in the SKIN and EDEMA, known as MYXEDEMA. It may be primary or secondary due to other pituitary disease, or hypothalamic dysfunction.	Central Hypothyroidism,Primary Hypothyroidism,Secondary Hypothyroidism,TSH Deficiency,Thyroid-Stimulating Hormone Deficiency,Central Hypothyroidisms,Deficiency, TSH,Deficiency, Thyroid-Stimulating Hormone,Hormone Deficiency, Thyroid-Stimulating,Hypothyroidism, Central,Hypothyroidism, Primary,Hypothyroidism, Secondary,Hypothyroidisms,Primary Hypothyroidisms,Secondary Hypothyroidisms,TSH Deficiencies,Thyroid Stimulating Hormone Deficiency,Thyroid-Stimulating Hormone Deficiencies
D008297	Male		Males
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D011446	Prospective Studies	Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.	Prospective Study,Studies, Prospective,Study, Prospective
D005260	Female		Females
D005500	Follow-Up Studies	Studies in which individuals or populations are followed to assess the outcome of exposures, procedures, or effects of a characteristic, e.g., occurrence of disease.	Followup Studies,Follow Up Studies,Follow-Up Study,Followup Study,Studies, Follow-Up,Studies, Followup,Study, Follow-Up,Study, Followup
D006258	Head and Neck Neoplasms	Soft tissue tumors or cancer arising from the mucosal surfaces of the LIP; oral cavity; PHARYNX; LARYNX; and cervical esophagus. Other sites included are the NOSE and PARANASAL SINUSES; SALIVARY GLANDS; THYROID GLAND and PARATHYROID GLANDS; and MELANOMA and non-melanoma skin cancers of the head and neck. (from Holland et al., Cancer Medicine, 4th ed, p1651)	Cancer of Head and Neck,Head Cancer,Head Neoplasm,Head and Neck Cancer,Head and Neck Neoplasm,Neck Cancer,Neck Neoplasm,Neck Neoplasms,Neoplasms, Upper Aerodigestive Tract,UADT Neoplasm,Upper Aerodigestive Tract Neoplasm,Upper Aerodigestive Tract Neoplasms,Cancer of Head,Cancer of Neck,Cancer of the Head,Cancer of the Head and Neck,Cancer of the Neck,Head Neoplasms,Head, Neck Neoplasms,Neoplasms, Head,Neoplasms, Head and Neck,Neoplasms, Neck,UADT Neoplasms,Cancer, Head,Cancer, Neck,Cancers, Head,Cancers, Neck,Head Cancers,Neck Cancers,Neoplasm, Head,Neoplasm, Neck,Neoplasm, UADT,Neoplasms, UADT
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000206	Actuarial Analysis	The application of probability and statistical methods to calculate the risk of occurrence of any event, such as onset of illness, recurrent disease, hospitalization, disability, or death. It may include calculation of the anticipated money costs of such events and of the premiums necessary to provide for payment of such costs.	Analysis, Actuarial,Actuarial Analyses,Analyses, Actuarial
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults