The University of Texas M.D. Anderson Cancer Center is studying a drug that may save thyroid cancer patients time, inconvenience, and discomfort.
M.D. Anderson is one of 14 institutions worldwide studying synthetic recombinant thyroid stimulating hormone, or TSH (Thyrogen; Genzyme, Inc, Massachusetts). The drug is given to thyroid cancer patients preparing to have a radioiodine scan.
In the past, patients scheduled for the radioiodine scan were required to stop their thyroid hormone replacement therapy. This hormone "drain," which allows the radioiodine to give the most accurate image, takes approximately 5 weeks. This period leaves many patients with severe symptoms of fatigue, bloating, weight gain, muscle swelling, and depression and continues for about 2 weeks after the patient has had the scan and resumes medication.
The phase III study of recombinant TSH tests whether future patients will be able to forego the hormone "drain." Instead, the synthetic hormone could be given in a series of injections before the scan while the patient continues his or her regular hormone medication without interruption. This possibly could save the patient the discomfort associated with the suspension of the medication.
Recombinant TSH is a synthetic substitute for the substance normally produced by the pituitary gland when thyroid hormone levels decline. High levels of TSH are necessary to make the thyroid an absorbent "sponge" for an effective radioiodine test. However, elevated TSH levels may also stimulate tumor growth. Recombinant TSH may provide the temporary TSH boost to make the radioiodine scan effective while reducing the chances of tumor growth.
Possible Cure With Less Severe Side Effects
The purpose of the new study is to demonstrate whether injection of recombinant TSH is as effective as stopping hormone medication with regard to getting accurate radioiodine test results.
"Potentially, this new drug may save patients a tremendous amount of physical discomfort and emotional distress," said Dr. Steven I. Sherman, the endocrinologist who is spearheading the study at M. D. Anderson. "Thyroid cancer is a very curable disease, and this will hopefully be one more way to get our patients back on their feet more quickly without missing a beat at home or work."
Although some patients have reported side effects of nausea, fatigue and headache from the new drug, they are minimal compared to the conventional regimen.
Thyroid cancer is a rare disease with fewer than 200,000 cases in the United States; about 13,000 new cases are diagnosed annually. It is a very treatable with surgery and radioiodine, with 85% to 90% of patients considered cured.
The recombinant TSH study is open to any thyroid cancer patient who would require a radioiodine scan, regardless of where he or she was diagnosed or underwent treatment, and will require 8 to 10 visits to M.D. Anderson over about a 6-week period. Patients must have had thyroidectomies or a series of surgeries that would be equivalent to a thyroidectomy.
Individuals who would like more information about the study should call Dr. Sherman's office at (713) 796-7879.