Tyrosine kinase inhibitors induced thyroid dysfunction: myth or reality?

Area of Science:

• Hematology
• Endocrinology
• Oncology

Background:

• Chronic myelogenous leukemia (CML) is a stem cell disorder characterized by the BCR-ABL fusion gene (Philadelphia chromosome).
• Thyroid dysfunction is a potential side effect of various cancer therapies.

Purpose of the Study:

• To prospectively evaluate thyroid function in newly diagnosed CML patients undergoing imatinib treatment.
• To assess the impact of imatinib on thyroid-stimulating hormone (TSH) levels and thyroid status.

Main Methods:

• Prospective study of 26 BCR-ABL positive CML patients.
• Thyroid function assessed at baseline and 6 months of imatinib therapy.
• Thyroid-stimulating hormone (TSH) levels were measured.

Main Results:

• TSH levels showed a statistically significant increase from baseline after 6 months of imatinib (3.20 ± 0.978 vs. 3.724 ± 1.726 mIU/L, p < 0.05).
• 88.4% of patients remained euthyroid.
• Only 3 patients (2 with subclinical hypothyroidism, 1 with hypothyroidism) developed thyroid issues.

Conclusions:

• Imatinib therapy did not demonstrate a significant adverse effect on overall thyroid function in CML patients.
• The majority of patients maintained normal thyroid status during 6 months of imatinib treatment.