Source: Circulation  |  Posted 11 years ago

Italian researchers say that the administration of human recombinant thyroid-stimulating hormone can help patients with advanced differentiated thyroid cancer avoid 1-thyroxine suppressive therapy withdrawal, maintain metabolic homeostasis and stave off the debilitating sequelae of hypothyroidism.

Researchers at the University of Pisa, Italy, enrolled 12 totally or near-totally thyroidectomized adults with metastatic or locally invasive differentiated thyroid cancer. Patients underwent iodone-131 (131-I) treatment while euthyroid on 1-thyroxine suppressive therapy (1-T4) after administration of human recombinant thyroid-stimulating hormone (rhTSH). Nine of them had undergone prior therapy after 1-T4 withdrawal.

Of the 12 patients, nine underwent diagnostic whole body scanning after two consecutive daily intramuscular injections of rhTSH, 0.9 mg, and then received an identical second course of rhTSH to promote therapeutic 131-I uptake. Post-therapy whole body scanning was performed seven days later. Three patients received only rhTSH 131-I therapy.

Post-therapy whole body scanning showed that rhTSH administration promoted 131-I uptake in all patients, Dr. Francesco Lippi and colleagues said. The use of rhTSH also significantly increased serum Tg concentrations.

At the most recent measurement three to 12 months after therapy, serum Tg levels had decreased in four and stabilized in two of eleven patients. Whole body scanning eight months after the end of the study indicated a decreased metastatic site in one patient.

Overall, rhTSH was well-tolerated. Mild, transient fever and/or nausea occurred only in a few patients. Individuals with bone metastases developed peritumoral pain and swelling to a similar degree but for a shorter length of time than other patients after 1-T4 withdrawal.

The authors say their results demonstrate that rhTSH administration can safely and successfully promote 131-I uptake in advanced thyroid cancer, thereby obviating 1-T4 withdrawal and hypothyroidism.