Researchers explore atypical treatments for medullary thyroid cancer

Given that the survival rate for medullary thyroid cancer is not as optimal as those of more common forms of the disease, researchers in Germany have been exploring alternative treatments for instances in which medullary carcinomas do not respond well to radioactive iodine treatment.

Scientists at the University Hospital Bonn recently published an article examining the efficacy of tyrosine kinase inhibitors, radiopeptide therapy and iodine-131 metaiodobenzylguanidine (MIBG) in treating medullary thyroid cancer or its symptoms.

Their results, which appear in the journal Seminars in Nuclear Medicine, are encouraging.

Medullary thyroid cancer originates in thyroid gland cells, called C cells, that produce a hormone called calcitonin, the National Institutes of Health states. Unlike papillary or follicular thyroid cancer, which are more common forms of the disease, medullary thyroid cancer is not as likely to be caused by irradiation of the neck in childhood.

The study's authors first looked at tyrosine kinase inhibitors, which are medications that interfere with the actions of certain enzymes within specific cells. In a review of the fast-growing literature on tyrosine kinase inhibitors, the team said that most clinical trials showed between 15 and 50 percent partial responses to the drug.

Researchers noted that the side effects of the medication did not appear to outweigh its potential benefits.

The authors also examined the effectiveness of peptide receptor radionuclide therapy, a treatment in which radioactive molecules are used to target particular peptide receptors on thyroid cells.

They said that although there is little data currently available on this treatment, its low number of side effects is promising.

Finally, the group discussed the use of radio-iodinated MIBG in palliative care for medullary thyroid cancer. When the disease is sufficiently advanced, involving the lymph nodes, its 10-year survival rate drops to 75 percent. If medullary carcinomas metastasize as distant tumors in the body, the team said that the rate goes as low as 40 percent.

MIBG therapy targets aggressively growing thyroid cancer cells, like the preceding treatments. The group noted that MIBG can slow tumor progression and improve quality-of-life for patients with medullary thyroid cancer, though they added that it is typically used for terminal cases.

If caught early, medullary thyroid cancer has an 80 percent survival rate, according to the Columbia University Department of Surgery.