Nilotinib-induced hypothyroidism in a patient with chronic myeloid leukemia

Tyrosine Kinase Inhibitors and Thyroid Toxicity

Some multithyrosine kinase inhibitors have been reported to cause changes in thyroid function. For the management of sunitinib-induced hypothyroidism, an evaluation of thyroid hormone and antibody profile is recommended before starting treatment with tyrosine kinase inhibitors. Patients with pre-existing thyroid dysfunction should undergo dose adjustment of L-thyroxine during treatment with tyrosine kinase inhibitors. Thyroid dysfunction is not a reason to discontinue or reduce the dosage of sunitinib. Their occurrence appears to correlate with increased antitumour efficacy of the inhibitor. There are currently no guidelines for monitoring thyroid activity during treatment with TKIs, and the time interval at which TSH should be periodically measured has not yet been determined. A reasonable approach is to monitor thyroid function, both before and during 2-4 weeks after the end of therapy. A comprehensive analysis of adverse events associated with the use of these inhibitors could help clinical monitoring of patients along with the adoption of appropriate management approaches.

Use patterns of first-line inhibitors of tyrosine kinase and time to change to second-line therapy in chronic myeloid leukemia

Background Chronic myeloid leukemia (CML) has a low incidence but a high burden of disease, and is treated with high-cost tyrosine kinase inhibitors (TKI). Objective To determine the time from the start of a first-line TKI until it passes to second-line, and to establish the reasons for the change of therapy time. Setting Patients with Philadelphia-positive CML treated with some TKI. Methods Retrospective cohort study, between January 1 2007 and July 31 2015, with information obtained from medical records, the time to change initial drugs to secondline therapy, and the reasons for change, were identified. Kaplan-Meier survival analysis was carried out. Main outcome measure A change in therapy to the secondline TKI and the final reason for the change of therapy. Results A total of 247 patients treated were found in 22 cities in Colombia with a mean age of 53.2 ± 15.2 years. The drug most used as initial therapy was imatinib; 53.8% of cases had to change to another TKI. 50% of patients changed therapy in 42 months, men in 24 and women in 67 months (95% CI 14.314-33.686; p = 0.001). Being male (OR 2.23; 95% CI 1.291-3.854; p = 0.004) and receiving hydroxyurea (OR 3.65; 95% CI 1.601-8.326; p = 0.002) were associated with a higher probability of switching to nilotinib or dasatinib, while receiving a new-generation TKI (OR 0.15; 95% CI 0.071-0.341; p < 0.001) reduced this risk. Conclusions A high proportion of patients needed to change to a second line with nilotinib and dasatinib management. It is necessary to obtain more real world evidence, to improve the effectiveness, adherence and safety of the treatment.

Vascular and Metabolic Implications of Novel Targeted Cancer Therapies: Focus on Kinase Inhibitors

Novel targeted cancer therapies, especially kinase inhibitors, have revolutionized the treatment of many cancers and have dramatically improved the survival of several types of malignancies. Because kinases not only are important in cancer development and progression, but also play a critical role in the cardiovascular (CV) system and metabolic homeostasis, important CV and metabolic sequelae have been associated with several types of kinase inhibitors. This paper reviews the incidences and highlights potential mechanisms of vascular and metabolic perturbations associated with 3 classes of commonly used kinase inhibitors that target the vascular endothelial growth factor signaling pathway, the ABL kinase, and the phosphoinositide 3-kinase/AKT/mammalian target of rapamycin signaling pathway. We propose preventive, screening, monitoring, and management strategies for CV care of patients treated with these novel agents.

Endocrine side-effects of anti-cancer drugs: thyroid effects of tyrosine kinase inhibitors

Tyrosine kinase inhibitors (TKIs) are currently used by most oncologists. Among their side effects, thyroid dysfunctions are nowadays clearly observed. Whereas changes in thyroid function tests have been originally described with sunitinib, we now know that many TKIs can induce hypothyroidism and hyperthyroidism. In this study, the various molecules implicated in thyroid dysfunctions are analysed and the latest data on physiopathological mechanisms are approached in order to propose a strategy of thyroid monitoring of patients on TKI therapy.

Thyroid dysfunctions induced by tyrosine kinase inhibitors

INTRODUCTION

Recently, tyrosine kinase inhibitors (TKIs) have emerged as a new class of anticancer therapy. Although generally considered less toxic than cytotoxic chemotherapy, TKIs do cause significant side effects including fatigue and hypertension. In addition, thyroid dysfunction is a well-known adverse effect of TKI.

AREAS COVERED

This review provides a comprehensive assessment of TKI-induced thyroid dysfunctions by sunitinib, sorafenib, pazopanib, imatinib, dasatinib, nilotinib, vandetanib, axitinib, motesanib and tivozanib. Furthermore, the potential mechanisms that result in this toxicity, the clinical impact of thyroid dysfunction in these patients and the controversies regarding treatment with thyroid hormone (TH) therapy are evaluated.

EXPERT OPINION

Detection of TKI-induced thyroid dysfunction requires routine monitoring of thyroid function and may necessitate treatment. Potential benefits in developing thyroid dysfunction and potential harm in treating it necessitate controlled studies. Finally, if treatment is pursued, appropriate dosing and timing of TH replacement will require prospective clinical evaluation.

Tyrosine kinase inhibitor-induced thyroid disorders: a review and hypothesis

BACKGROUND

Thyroid dysfunction is a well-known adverse effect of sunitinib, a drug that targets multiple receptor tyrosine kinases, including vascular endothelial growth factor receptor (VEGFR). As several kinds of tyrosine kinase inhibitors (TKIs) are now available, this has been postulated to be a side effect of the TKIs that target the VEGFR (VEGF-TKIs). However, sunitinib, one of the first-generation TKIs, likely causes thyroid dysfunction more frequently than other TKI classes, leading not only to hypothyroidism, but also to thyrotoxicosis.

SUMMARY

Based on the reports published to date, including our own studies, we have hypothesized that sunitinib may exert these effects, because it targets a broad spectrum of tyrosine kinases. This not only includes VEGFR2, but also VEGFR1 and the platelet-derived growth factor receptor (PDGFR). This, in turn, may suggest that not only VEGFR2 but also the PDGFR and/or the VEGFR1 play an important role during angiogenesis in the thyroid.

CONCLUSIONS

Our current hypothesis may explain the mechanisms that underlie TKI-induced thyroid disorders. By learning how various kinds of TKIs affect thyroid function, we may elucidate how the angiogenesis in thyroid is regulated both physiologically and pathologically.