Association between development of hypothyroidism and improved survival in patients with head and neck cancer

CXCL9 mediating the effect of thyroid disorders on oral and oropharyngeal cancer risk: A mediation Mendelian randomization study

INTRODUCTION

The established association between thyroid disorders (TD) and its two main subtypes-hyperthyroidism and hypothyroidism-and the incidence of oral and oropharyngeal cancer (OCPC) has been substantiated. However, the direct causal relationship and potential intermediary mechanisms linking these conditions have not been clearly defined in prior studies.

MATERIAL & METHODS

This study employed univariate Mendelian randomization (MR) analysis to explore those relationship. Instrumental variables from genome-wide association study (GWAS) datasets for TD (n = 218,792), hyperthyroidism (n = 460,499), hypothyroidism (n = 213,990), and OCPC (n = 12,619), along with 41 intermediary inflammatory cytokines (n = 8293), were analyzed. Inverse variance weighting (IVW) method assessed the causal relationships, while summary MR analysis with pQTL datasets from decode and 91 inflammatory cytokines explored the cytokines' roles as biomarkers and therapeutic targets for OCPC. Multivariable MR (MVMR) analysis quantified the mediation effect of these cytokines in the TD-OCPC relationship.

RESULTS

UVMR analysis provided strong evidence for a causal relationship between TD (OR = 1.376, 95 % CI = 1.142-1.656, p = 0.001), hyperthyroidism (OR = 1.319, 95 % CI=1.129-1.541, p = 0.001), hypothyroidism (OR = 1.224, 95 % CI = 1.071-1.400, p = 0.003), and the risk of OCPC. CXCL9 was identified as a significant intermediary in mediating the risk of OCPC from TD and its two subtypes (OR = 1.218, 95 % CI = 1.016-1.461, P = 0.033), suggesting its potential as a predictive biomarker for OCPC. MVMR analysis further revealed that CXCL9 mediated 7.94 %, 14.4 %, and 18 % of the effects of TD, hyperthyroidism, and hypothyroidism on OCPC risk, respectively.

DISCUSSION

This study not only elucidated the potential causal relationships between TD including its two subtypes and OCPC risk, but also highlighted CXCL9 as a pivotal mediator in this association.

Low free triiodothyronine and immune-related hyperthyroidism are associated with overall and progression-free survival in head and neck squamous cell carcinoma treated with pembrolizumab

INTRODUCTION

Thyroid function is frequently impaired in recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC). In patients treated with pembrolizumab, immune-related adverse events (irAEs) of the thyroid are common. However, the prognostic significance of baseline and on-treatment thyroid dysfunction is currently unclear.

METHODS

This study included 95 patients who received pembrolizumab for R/M HNSCC between 2016 and 2022. Baseline thyroid status, according to serum hormone levels, and irAEs were assessed. Univariable and multivariable Cox regression analyses were performed for overall survival (OS) and progression-free survival (PFS). Furthermore, the best overall response according to the prognostic groups was examined.

RESULTS

Low fT3 (HR: 2.52, p = 0.006), immune-related hyperthyroidism (HR: 0.11, p = 0.038), ECOG performance status ≥2 (HR: 3.72, p = 0.002), and platinum-refractory disease (HR: 3.29, p = 0.020) were independently associated with OS. Furthermore, immune-related hyperthyroidism was associated with longer PFS (HR: 0.13, p = 0.007), a higher objective response rate (83% vs. 31%, p = 0.018), and a higher disease control rate (100% vs. 43%, p = 0.008). Thyroid-related autoantibodies were elevated in 40% of thyroid irAEs cases with available measurements. Out of 16 thyroid irAEs, 15 occurred in patients with fT3 above the lower limit of normal.

CONCLUSION

Low fT3 was associated with worse OS. Immune-related hyperthyroidism was correlated with both improved OS and PFS. Baseline fT3 assessment and close on-treatment monitoring of serum thyroid levels may be valuable for risk stratification in R/M HNSCC patients receiving pembrolizumab.

FT3 to FT4 Conversion Ratio May Be an Independent Prognostic Factor in Pancreatic Cancer Patients

Preclinical evidence suggests that T4 can promote tumor growth while T3 can act conversely; therefore, the fT3 and fT4 concentrations should affect overall survival (OS) in cancer patients. The objective of the study was to look for an association between thyroid hormone concentrations in peripheral blood and OS in the pancreatic adenocarcinoma (PDAC) patients group. We included, retrospectively, 15 PDAC patients, without thyroid dysfunction under treatment, who underwent radical surgery, with no prior history of anticancer therapy. TSH, fT3, and fT4 concentrations were determined in blood samples taken preoperatively. We found that the fT3/fT4 ratio categorized into two groups (<0.22 vs. ≥0.22) dichotomized the study population into poor and good prognosis subgroups (log-rank p = 0.03; OS medians, respectively: 3 and 14 months), being a statistically significant predictor both in uni- and multivariate Cox regression analysis. We conclude that the importance of fT4 into fT3 conversion means not just its standard metabolic effects as the final products of thyroid gland activity. We hypothesize that it is linked to the progression of pancreatic malignancies, either via thyroid hormone receptors or indirectly, by interaction with cancer cells product.

The Hypothalamic-Pituitary-Thyroid Axis Equivalent in Normal and Cancerous Oral Tissues: A Scoping Review

The hypothalamic-pituitary-thyroid (HPT) axis is crucial in regulating thyroid hormone levels that contribute to the development and homeostasis of the human body. Current literature supports the presence of a local HPT axis equivalent within keratinocytes of the skin, with thyroid hormones playing a potential role in cancer progression. However, this remains to be seen within oral tissue cells. An electronic search of Scopus and PubMed/Medline databases was conducted to identify all original publications that reported data on the production or effects of HPT axis components in normal or malignant cells of the oral cavity. The search identified 221 studies, of which 14 were eligible. Eight studies were retrospective analyses of clinical samples, one study involved both in vivo and in vitro experiments, and the remaining five studies were conducted in vitro using cell lines. The search identified evidence of effects of HPT components on oral cancer cells. However, there were limited data for the production of HPT axis components by oral tissues. We conclude that a possible role of the local HPT axis equivalent in the oral mucosa may not be established at present. The gaps in knowledge identified in this scoping review, particularly regarding the production of HPT components by oral tissues, warrant further investigation.

Prognostic value of hypothyroidism in patients undergoing intensity-modulated radiation therapy for nasopharyngeal carcinoma

BACKGROUND

The purpose of this study was to investigate the effect of hypothyroidism and thyroxine replacement therapy on the prognosis of nasopharyngeal carcinoma (NPC) patients.

METHODS

The clinical data of 284 NPC patients, who received intensity-modulated radiation therapy (IMRT) between January 2011 and December 2016, were retrospectively analyzed.

RESULTS

Hypothyroidism occurred in 38% of patients. Patients with hypothyroidism had significantly better disease-free survival (DFS) (p = 0.002) and relapse-free survival (RFS) (p = 0.008). Multivariate analysis showed that hypothyroidism was a positive independent prognostic factor (DFS and RFS). Among the patients with hypothyroidism, thyroxine replacement therapy did not yield inferior survival (DFS, RFS, all p > 0.05).

CONCLUSIONS

The NPC patients with complete response are at risk of hypothyroidism, which is attributable to escalating dose. These patients experienced clinical hypothyroidism could be adequately treated with thyroid hormone replacement. Further investigation of the underlying biological mechanism and potential therapeutic implications are required.

µ-Crystallin Is Associated with Disease Outcome in Head and Neck Squamous Cell Carcinoma

Thyroid hormone levels may be associated with disease outcome in head and neck squamous cell carcinoma (HNSCC). µ-Crystallin (CRYM), a thyroid hormone binding protein, blocks intracellular binding of the thyroid hormone T3 to its receptors. In this study, we aimed to analyze the association of CRYM levels with disease outcome in HNSCC patients. We retrospectively assessed immunohistochemical CRYM expression in 121 head and neck cancer patients. Preoperative thyrotropin levels could be extracted for 50 patients. Patients with low thyrotropin levels had a worse prognosis compared to euthyroid patients (5-year overall survival TSH low 20% vs. TSH norm 58%). We observed an association of CRYM+ patients with improved overall survival (5-year overall survival for CRYM+ 78.6% vs. CRYM- 56%). Interaction analysis between CRYM and HPV revealed that this effect was limited to HPV- patients (CRYM+|HPV- HR 0.12, 95% CI 0.01-0.87, p = 0.036). These results were replicated in an independent dataset. CRYM expression identified patients with favorable disease progression for HPV- HNSCC patients and could serve as a useful biomarker in this patient population. This study further confirms a correlation of thyroid hormone levels with adverse disease outcome in HNSCC patients, which could be potentially exploited as a therapeutic target.

Thyroid hormones concentration in portal and peripheral blood in patients with pancreatic cancer: Preliminary study

BACKGROUND

The prognostic value of D-dimers concentration in portal blood in patients with pancreatic cancer has been established in several studies. Thyroid hormones and their receptors, especially T3 also seems to have a specific role in process of neoplasia and metastatic spread.

OBJECTIVE

The aim of the study was to look for changes of thyroid hormones concentration between portal and peripheral blood.

METHODS

We included prospectively 8 patients with pancreatic cancer, without liver dysfunction, qualified to surgical treatment. D-dimers, THS, fT3, fT4 concentration was determined in blood samples from portal and peripheral vein taken intraoperatively.

RESULTS

The difference and quotient of portal and peripheral concentration of D-dimers, THS, fT3 and fT4 was calculated (D-dimer-; THS-; fT3-; fT4-d and -q). The level of D-dimers measured in portal blood was > 2700 ng/mL in 3 patients. The peripheral fT3 level was significantly higher In high portal D-dimers group. FT3 change coefficients showed strong statistically significant negative correlation with portal D-dimer concentration level.

CONCLUSIONS

We suggest that fT3 or its receptors can influence progression of pancreatic malignancies. The results of this study are also a new evidence that both fT3 and portal D-dimers are biologically linked to intensity of local neoplastic process. Nevertheless, deeper knowledge about portal circulation probably constitute missing part in understanding nature of pancreatic neoplasia. Investigations both on larger group and in the field of basic sciences are needed.

Actions of Thyroid Hormones on Thyroid Cancers

L-Thyroxine (T4) is the principal ligand of the thyroid hormone analogue receptor on the extracellular domain of integrin αvβ3. The integrin is overexpressed and activated in cancer cells, rapidly dividing endothelial cells, and platelets. The biologic result is that T4 at physiological concentration and without conversion to 3,3',5-triiodo-L-thyronine (T3) may stimulate cancer cell proliferation and cancer-relevant angiogenesis and platelet coagulation. Pro-thrombotic activity of T4 on platelets is postulated to support cancer-linked blood clotting and to contribute to tumor cell metastasis. We examine some of these findings as they may relate to cancers of the thyroid. Differentiated thyroid cancer cells respond to physiological levels of T4 with increased proliferation. Thus, the possibility exists that in patients with differentiated thyroid carcinomas in whom T4 administration and consequent endogenous thyrotropin suppression have failed to arrest the disease, T4 treatment may be stimulating tumor cell proliferation. In vitro studies have shown that tetraiodothyroacetic acid (tetrac), a derivative of T4, acts via the integrin to block T4 support of thyroid cancer and other solid tumor cells. Actions of T4 and tetrac or chemically modified tetrac modulate gene expression in thyroid cancer cells. T4 induces radioresistance via induction of a conformational change in the integrin in various cancer cells, although not yet established in thyroid cancer cells. The thyroid hormone receptor on integrin αvβ3 mediates a number of actions of T4 on differentiated thyroid cancer cells that support the biology of the cancer. Additional studies are required to determine whether T4 acts on thyroid cancer cells.

Nongenomic Actions of Thyroid Hormone: The Integrin Component

The extracellular domain of plasma membrane integrin αvβ3 contains a cell surface receptor for thyroid hormone analogues. The receptor is largely expressed and activated in tumor cells and rapidly dividing endothelial cells. The principal ligand for this receptor is l-thyroxine (T₄), usually regarded only as a prohormone for 3,5,3'-triiodo-l-thyronine (T₃), the hormone analogue that expresses thyroid hormone in the cell nucleus via nuclear receptors that are unrelated structurally to integrin αvβ3. At the integrin receptor for thyroid hormone, T₄ regulates cancer and endothelial cell division, tumor cell defense pathways (such as anti-apoptosis), and angiogenesis and supports metastasis, radioresistance, and chemoresistance. The molecular mechanisms involve signal transduction via mitogen-activated protein kinase and phosphatidylinositol 3-kinase, differential expression of multiple genes related to the listed cell processes, and regulation of activities of other cell surface proteins, such as vascular growth factor receptors. Tetraiodothyroacetic acid (tetrac) is derived from T₄ and competes with binding of T₄ to the integrin. In the absence of T₄, tetrac and chemically modified tetrac also have anticancer effects that culminate in altered gene transcription. Tumor xenografts are arrested by unmodified and chemically modified tetrac. The receptor requires further characterization in terms of contributions to nonmalignant cells, such as platelets and phagocytes. The integrin αvβ3 receptor for thyroid hormone offers a large panel of cellular actions that are relevant to cancer biology and that may be regulated by tetrac derivatives.

Current and Future Molecular Targets for Acute Myeloid Leukemia Therapy

OPINION STATEMENT

Acute myeloid leukemia (AML) disease prognosis is poor and there is a high risk of chemo-resistant relapse for both young and old patients. Thus, there is a demand for alternative and target-specific drugs to improve the 5-year survival rate. Current treatment mainstays include chemotherapy, or mutation-specific targeting molecules including FLT3 inhibitors, IDH inhibitors, and monoclonal antibodies. Efforts to devise new, targeted therapy have included recent advances in methods for high-throughput genomic screening and the availability of computer-assisted techniques for the design of novel agents predicted to specifically inhibit mutant molecules involved in leukemogenesis. Crosstalk between the leukemia cells and the bone marrow microenvironment through cell surface molecules, such as the integrins αvβ3 and αvβ5, might influence drug response and AML progression. This review article focuses on current AML treatment options, new AML targeted therapies, the role of integrins in AML progression, and a potential therapeutic agent-integrin αvβ3 antagonist.

Tetrac as an anti-angiogenic agent in cancer

The thyroid hormones T3 and T4 have emerged as pro-angiogenic hormones with important implications for cancer management. Endogenous circulating hormone levels may help stimulate cancer progression and limit the effectiveness of anticancer therapy, though clinical data remain inconclusive. The capacity of thyroid hormones to modulate angiogenesis is mediated through non-canonical mechanisms initiated at the cell surface receptor integrin αvβ3. This integrin is predominantly expressed on tumour cells, proliferating endothelial cells and tumour stroma-associated cells, emphasising its potential relevance in angiogenesis and tumour biology. Thyroid hormone/integrin αvβ3 signalling results in the activation of intracellular pathways that are commonly associated with angiogenesis and are mediated through classical pro-angiogenic molecules such as vascular endothelial growth factor. The naturally occurring T4 analogue tetrac blocks the pro-angiogenic actions of thyroid hormones at the integrin receptor, in addition to agonist-independent anti-angiogenic effects. Tetrac reduces endothelial cell proliferation, migration and tube formation through a reduction in the transcription of vascular growth factors/growth factor receptors, hypoxia-inducible factor-1α, pro-angiogenic cytokines and a number of other pro-angiogenic genes, while at the same time stimulating the expression of endogenous angiogenesis inhibitors. It further modulates vascular growth factor activity by disrupting the crosstalk between integrin αvβ3 and adjacent growth factor receptors. Moreover, tetrac disrupts thyroid hormone-stimulated tumour recruitment, differentiation and the pro-angiogenic signalling of tumour stroma-associated mesenchymal stem cells. Tetrac affects tumour-associated angiogenesis via multiple mechanisms and interferes with other cancer cell survival pathways. In conjunction with its low toxicity and high tissue selectivity, tetrac is a promising candidate for clinical application.

Relationship between Hypothyroidism and Endometrial Cancer

Thyroid dysfunction is involved in several types of carcinoma. Hypothyroidism is one of the most common medical morbidities among patients with endometrial cancer; however, the related mechanism is unclear. Among the risk factors related to endometrial cancer, hypothyroidism interacts with metabolic syndrome, polycystic ovarian syndrome and infertility or directly acts on the endometrium itself, which may influence the development and progression of endometrial cancer. We summarize recent studies on the relationship between hypothyroidism and endometrial cancer and its risk factors to provide references for basic research as well as for clinical treatment and prognostic evaluation.

Clinical Implications and Impact of Discovery of the Thyroid Hormone Receptor on Integrin αvβ3-A Review

Hypothyroidism has been reported to improve survival in cancer patients but only recently has the putative mechanism been identified as a receptor for thyroxine and tri-iodothyronine on integrin αvβ3. Recognition of divergence of action of the pro-oncogenic L-thyroxine (T4) from pro-metabolic 3,5,3'-triiodo-L-thyronine (T3) has enabled clinical implementation whereby exogenous T3 may replace exogenous (or endogenous) T4 to maintain clinical euthyroid hypothyroxinemia that results in significantly better survival in advanced cancer patients without the morbidity of clinical hypothyroidism.

Thyroid Hormones and Cancer: A Comprehensive Review of Preclinical and Clinical Studies

Thyroid hormones take major part in normal growth, development and metabolism. Over a century of research has supported a relationship between thyroid hormones and the pathophysiology of various cancer types. In vitro studies as well as research in animal models demonstrated an effect of the thyroid hormones T3 and T4 on cancer proliferation, apoptosis, invasiveness and angiogenesis. Thyroid hormones mediate their effects on the cancer cell through several non-genomic pathways including activation of the plasma membrane receptor integrin αvβ3. Furthermore, cancer development and progression are affected by dysregulation of local bioavailability of thyroid hormones. Case-control and population-based studies provide conflicting results regarding the association between thyroid hormones and cancer. However, a large body of evidence suggests that subclinical and clinical hyperthyroidism increase the risk of several solid malignancies while hypothyroidism may reduce aggressiveness or delay the onset of cancer. Additional support is provided from studies in which dysregulation of the thyroid hormone axis secondary to cancer treatment or thyroid hormone supplementation was shown to affect cancer outcomes. Recent preclinical and clinical studies in various cancer types have further shown promising outcomes following chemical reduction of thyroid hormones or inhibition or their binding to the integrin receptor. This review provides a comprehensive overview of the preclinical and clinical research conducted so far.

Radioresistance of cancer cells, integrin αvβ3 and thyroid hormone

Radioresistance is a substantial barrier to success in cancer management. A number of molecular mechanisms support radioresistance. We have shown experimentally that the thyroid hormone analogue receptor on the extracellular domain of integrin αvβ3 may modulate the state of radiosensitivity of tumor cells. Specifically, tetraiodothyroacetic acid (tetrac), a derivative of L-thyroxine (T₄), can reduce radioresistance in cancer cells. In this review, we list a number of intrinsic signal transduction molecules and other host factors that have been reported to support/induce radioresistance in cancer cells and that are also subject to control by T₄ through actions primarily initiated at integrin αvβ3. Additional preclinical evidence is needed to support these radioresistance-relevant actions of thyroid hormone.

Hypothyroidism is associated with worse outcomes of hepatocellular carcinoma patients after liver transplantation

Background/Aims

Hypothyroidism has been associated with hepatocellular carcinoma (HCC) incidence; however, the relationship between hypothyroidism and HCC patient outcomes is unclear. We investigated the impact of hypothyroidism on outcomes after liver transplantation for HCC.

Materials and Methods

We retrospectively studied HCC patients transplanted between January 2000 and December 2015. Hypothyroidism was defined as a thyroid‐stimulating hormone (TSH) level continuously greater than 5 mIU/L, a documented history of hypothyroidism, or treatment with thyroid hormone replacement therapy. Multivariate Cox regression was used to assess the impact of hypothyroidism on overall survival (OS) and recurrence‐free survival (RFS) adjusting for potential confounders. Subgroup analyses and interaction tests were conducted to compare the impact of hypothyroidism in different subgroups and assess for possible synergistic effects. Sensitivity analyses were performed among different cohorts to verify the stability of the results.

Results

A total of 343 HCC patients who underwent liver transplantation were included in the analysis. The primary analysis was conducted among 288 patients diagnosed with HCC prior to transplantation. Hypothyroidism was independently associated with worse OS and RFS, as was elevated TSH. The adjusted hazard ratio (AHR) of hypothyroidism was 2.45 (95% confidence interval [CI], 1.44‐4.18) for OS and 5.54 (2.36, 13.01) for RFS. The AHR of TSH for OS was 1.05 (1.02, 1.09) and 1.08 (1.03, 1.13) for RFS. No interaction was found among different subgroups categorized by etiology and comorbidity. The results were stable to sensitivity analyses.

Conclusion

Hypothyroidism is associated with poorer overall and recurrence‐free survival of HCC patients receiving liver transplantation. These results require validation.

Contributions of Thyroid Hormone to Cancer Metastasis

Acting at a cell surface receptor on the extracellular domain of integrin αvβ3, thyroid hormone analogues regulate downstream the expression of a large panel of genes relevant to cancer cell proliferation, to cancer cell survival pathways, and to tumor-linked angiogenesis. Because αvβ3 is involved in the cancer cell metastatic process, we examine here the possibility that thyroid hormone as l-thyroxine (T4) and the thyroid hormone antagonist, tetraiodothyroacetic acid (tetrac), may respectively promote and inhibit metastasis. Actions of T4 and tetrac that are relevant to cancer metastasis include the multitude of synergistic effects on molecular levels such as expression of matrix metalloproteinase genes, angiogenesis support genes, receptor tyrosine kinase (EGFR/ERBB2) genes, specific microRNAs, the epithelial–mesenchymal transition (EMT) process; and on the cellular level are exemplified by effects on macrophages. We conclude that the thyroid hormone-αvβ3 interaction is mechanistically linked to cancer metastasis and that modified tetrac molecules have antimetastatic activity with feasible therapeutic potential.

A novel thyroid function index associated with opposite therapeutic outcomes in advanced hepatocellular carcinoma patients receiving chemotherapy or sorafenib

AIM

A sustained proportion of advanced hepatocellular carcinoma (HCC) patients worldwide received either chemotherapy or sorafenib. However, to date, effective and convenient biomarkers to predict their therapeutic outcomes remained elusive. Hypothyroidism was associated with favorable anticancer treatment outcomes in several advanced cancers. Here, we aimed to investigate the potential of using thyroid-stimulating hormone (TSH) and free T4 (FT4) levels as biomarkers to predict clinical outcomes in HCC patients receiving chemotherapy or sorafenib.

METHODS

Total 123 advanced HCC patients at Barcelona Clinical Liver Cancer Stage C were included. They were separated into two cohorts, one treated by sorafenib (n = 62) and the other by chemotherapy (n = 61). Clinical data including TSH and FT4 were retrieved and correlated with treatment outcomes.

RESULTS

Because of restriction in local insurance policy, the baseline liver function reserve was better in patients receiving sorafenib. Therefore, the two cohorts were analyzed separately. The results showed that a higher (> median) TSH × FT4 value was independently associated with favorable time-to-tumor progression (P = 0.006) and overall survival (P = 0.002) if chemotherapy was provided; whereas it was associated with unfavorable time-to-tumor progression (P = 0.017) and overall survival (P = 0.001) if sorafenib was administrated. These opposite associations remained valid when patients with Child-Pugh class A liver function from either cohort were included for analysis.

CONCLUSION

A novel thyroid function index, TSH × FT4, significantly predicted opposite clinical outcomes in advanced HCC patients receiving sorafenib or chemotherapy treatment.

Risk Factors for New Hypothyroidism During Tyrosine Kinase Inhibitor Therapy in Advanced Nonthyroidal Cancer Patients

BACKGROUND

Thyroid dysfunction during tyrosine kinase inhibitor (TKI) cancer treatment is common, but predisposing risk factors have not been determined. Recommendations for monitoring patients treated with one or multiple TKI and in conjunction with other relevant cancer therapies could be improved. The study objective was to assess the risk factors for new thyroid dysfunction in TKI-treated previously euthyroid cancer patients.

METHODS

A retrospective cohort study of patients with advanced nonthyroidal cancer treated with TKI from 2000 to 2017, having available thyroid function tests showing initial euthyroid status, excluding patients with preexisting thyroid disease or lack of follow-up thyroid function tests. During TKI treatment, patients were classified as euthyroid (thyrotropin [TSH] normal), subclinical hypothyroidism (TSH 5-10 mIU/L, or higher TSH if free thyroxine normal), or overt hypothyroidism (TSH >10 mIU/L, low free thyroxine, or requiring thyroid hormone replacement). The timing of thyroid dysfunction and TKI used were assessed. Risk factors for incident hypothyroidism were evaluated using multivariate models.

RESULTS

In 538 adult patients included, subclinical hypothyroidism occurred in 71 (13.2%) and overt hypothyroidism occurred in 144 (26.8%) patients with TKI therapy, following a median cumulative TKI exposure of 196 days (interquartile range [IQR] 63.5-518.5 days). The odds of hypothyroidism were greatest during the first six months on a TKI. Median exposure time on the TKI concurrent with thyroid dysfunction in patients treated with only one TKI was 85 days (IQR 38-293.5 days) and was similar to the 74 days (IQR 38-133.3 days) in patients treated previously with other TKI (p = 0.41). Patients who developed hypothyroidism compared to those who remained euthyroid had greater odds of being female (odds ratio = 1.99 [confidence interval 1.35-2.93], p < 0.01), but greater cumulative TKI exposure and greater number of TKI received were not associated with thyroid dysfunction.

CONCLUSIONS

Thyroid dysfunction occurred in 40% of euthyroid patients. Monitoring thyroid function in TKI-treated patients is recommended, with particular attention to female patients and within the first six months of exposure to a new TKI.

Nonthyroidal Illness Syndrome and Thyroid Hormone Actions at Integrin αvβ3

CONTEXT

The nonthyroidal illness syndrome (NTIS) is a constellation of changes in circulating thyroid hormone levels that occur in euthyroid patients with acute or chronic systemic diseases. The changes that occur include a reduction in serum T3, an increase in serum rT3, and variable changes in circulating T4 levels. No consensus exists regarding therapeutic intervention for NTIS.

METHODS

We briefly review the published literature on the physiological actions of T4 and of rT3-hormones that until recently have been seen to have little or no bioactivity-and analyze the apparent significance of changes in circulating T4 and T3 encountered in the setting of NTIS in patients with cancer. In the case of T4, these actions may be initiated at a cancer or endothelial cell plasma membrane receptor on integrin αvβ3 or at the cytoskeleton.

RESULTS

This review examines possible therapeutic intervention in NTIS in patients with cancer in terms of T4 reduction and T3 support. Evidence also exists that rT3 may support cancer.

CONCLUSIONS

Prospective study is proposed of pharmacological reduction of normal or elevated T4 in cancer-associated NTIS. We also support investigation of normally circulating levels of T3 in such patients.

Radiotherapeutic factors affecting the incidence of developing hypothyroidism after radiotherapy for head and neck squamous cell cancer

PURPOSE

The purpose of this study is to determine radiotherapy (RT) dose-volumetric threshold of radiation-induced hypothyroidism (HT) in head and neck squamous cell carcinoma (HNSCC) patients.

PATIENTS AND METHODS

The diagnosis of HT in 78 HNSCC patients treated with RT was based on a thyroid stimulating hormone (TSH) level greater than the maximum value of laboratory range. In all patients, dose-volumetric parameters were analyzed according to their relation to development of HT, and thyroid volumes spared from doses ≥10, 20, 30, 40 and 50 Gy (V10, V20, V30, V40 and V50) were analyzed from the dose volume histograms (DVHs).

RESULTS

Median follow-up duration was 31 months. At the end of study, 33 patients (42.3%) developed HT and the cumulative incidence of HT was 24.6%, 36.5% and 42.3% at one, two and three years, respectively. V30 of 42.1% (P = 0.005) was defined as dose-volumetric threshold of radiation-induced HT in HNSCC patients. Our analysis showed that V30 separates patients into low- and high-risk groups; the incidence of radiation-induced HT in the group with V30 < 42.1% and V30 ≥ 42.1% was 29.4% and 71.4%, respectively (P = 0.002).

CONCLUSIONS

The V30 may predict risk of developing HT after RT for HNSCC patients. V30 of 42.1%, defined as dose-volumetric threshold of radiation-induced HT, can be useful in treatment planning of HNSCC patients.

The induction of myeloma cell death and DNA damage by tetrac, a thyroid hormone derivative

Multiple myeloma (MM) is a plasma cell malignancy in which involvement of the thyroid hormone-integrin αvβ3 pathway was shown, and pharmacologic inhibition of this pathway is a rational approach to disease management. A thyroid hormone derivative, tetraiodothyroacetic acid (tetrac), which inhibits l-thyroxine (T₄) and 3,5,3'-triiodo-l-thyronine (T₃) binding to αvβ3 integrin, was studied in five MM cell lines and primary bone marrow (BM) MM cells. Tetrac inhibited MM cell proliferation (absolute cell number/viability) and induced caspase-dependent apoptosis (annexin-V/PI and cell cycle). Activation of caspase-9 and caspase-3 was further demonstrated. Moreover, DNA damage markers, ataxia-telangiectasia-mutated (ATM) kinase, poly ADP-ribose polymerase (PARP-1) and histone γH2AX were induced by tetrac. The various tetrac-initiated effects were attenuated by Arg-Gly-Asp (RGD) peptide, suggesting integrin involvement. Primary BM mononuclear cells were harvested from MM patients (n = 39) at various disease stages. Tetrac-induced apoptosis (12/17 samples) and sensitized the cytotoxic action of bortezomib (6/9 samples). Lastly, expression of plasma membrane integrin αvβ3 was shown not only in the malignant plasma clone, but also in other cell populations within the BM samples (n = 25). Tetrac is anti-proliferative and pro-apoptotic in MM and cells may offer a therapeutic approach for this disease.

Molecular Basis of Nongenomic Actions of Thyroid Hormone

Nongenomic actions of thyroid hormone are initiated by the hormone at receptors in the plasma membrane, in cytoplasm, or in mitochondria and do not require the interaction of nuclear thyroid hormone receptors (TRs) with their primary ligand, 3,5,3'-triiodo-l-thyronine (T₃). Receptors involved in nongenomic actions may or may not have structural homologies with TRs. Certain nongenomic actions that originate at the plasma membrane may modify the state and function of intranuclear TRs. Reviewed here are nongenomic effects of the hormone-T₃ or, in some cases, l-thyroxine (T₄)-that are initiated at (a) truncated TRα isoforms, e.g., p30 TRα1, (b) cytoplasmic proteins, or (c) plasma membrane integrin αvβ3. p30 TRα1 is not transcriptionally competent, binds T₃ at the cell surface, and consequently expresses a number of important functions in bone cells. Nongenomic hormonal control of mitochondrial respiration involves a TRα isoform, and another truncated TRα isoform nongenomically regulates the state of cellular actin. Cytoplasmic hormone-binding proteins involved in nongenomic actions of thyroid hormone include ketimine reductase, pyruvate kinase, and TRβ that shuttle among intracellular compartments. Functions of the receptor for T₄ on integrin αvβ3 include stimulation of proliferation of cancer and endothelial cells (angiogenesis) and regulation of transcription of cancer cell survival pathway genes. T₄ serves as a prohormone for T₃ in genomic actions of thyroid hormone, but T₄ is a hormone at αvβ3 and more important to cancer cell function than is T₃. Thus, characterization of nongenomic actions of the hormone has served to broaden our understanding of the cellular roles of T₃ and T₄.

Actions of l-thyroxine and Nano-diamino-tetrac (Nanotetrac) on PD-L1 in cancer cells

The PD-1 (programmed death-1)/PD-L1 (PD-ligand 1) checkpoint is a critical regulator of activated T cell-cancer cell interactions, defending tumor cells against immune destruction. Nano-diamino-tetrac (NDAT; Nanotetrac) is an anticancer/anti-angiogenic agent targeted to the thyroid hormone-tetrac receptor on the extracellular domain of integrin αvβ3. NDAT inhibits the cancer cell PI3-K and MAPK signal transduction pathways that are critical to PD-L1 gene expression. We examined actions in vitro of thyroid hormone (l-thyroxine, T₄) and NDAT on PD-L1 mRNA abundance (qPCR) and PD-L1 protein content in human breast cancer (MDA-MB-231) cells and colon carcinoma (HCT116 and HT-29) cells. In MDA-MB-231 cells, a physiological concentration of T₄ (10^-7M total; 10^-10M free hormone) stimulated PD-L1 gene expression by 38% and increased PD-L1 protein by 2.7-fold (p<0.05, all changes). NDAT (10^-7M) reduced PD-L1 in T₄-exposed cells by 21% (mRNA) and 39% (protein) (p<0.05, all changes). In HCT116 cells, T₄ enhanced PD-L1 gene expression by 17% and protein content by 24% (p<0.05). NDAT reduced basal PD-L1 mRNA by 35% and protein by 31% and in T₄-treated cells lowered mRNA by 33% and protein by 66%. In HT-29 cells, T₄ increased PD-L1 mRNA by 62% and protein by 27%. NDAT lowered basal and T₄-stimulated responses in PD-L1 mRNA and protein by 35-40% (p<0.05). Activation of ERK1/2 was involved in T₄-induced PD-L1 accumulation. We propose that, by a nongenomic mechanism, endogenous T₄ may clinically support activity of the defensive PD-1/PD-L1 checkpoint in tumor cells. NDAT non-immunologically suppresses basal and T₄-induced PD-L1 gene expression and protein accumulation in cancer cells.

Thyroid hormones and their membrane receptors as therapeutic targets for T cell lymphomas

Thyroid hormones (THs) are important regulators of metabolism, differentiation and cell proliferation. They can modify the physiology of human and murine T cell lymphomas (TCL). These effects involve genomic mechanisms, mediated by specific nuclear receptors (TR), as well as nongenomic mechanisms, that lead to the activation of different signaling pathways through the activation of a membrane receptor, the integrin αvβ3. Therefore, THs are able to induce the survival and growth of TCL. Specifically, the signaling induced by THs through the integrin αvβ3 activates proliferative and angiogenic programs, mediated by the regulation of the vascular endothelial growth factor (VEGF). The genomic or pharmacologic inhibition of integrin αvβ3 reduces the production of VEGF and induces cell death both in vitro and in xenograft models of human TCL. Here we review the mechanisms involved in the modulation of the physiology of TCL induced by THs, the analysis of the interaction between genomic and nongenomic actions of THs and their contribution to T cell lymphomagenesis. These actions of THs suggest a novel mechanism for the endocrine modulation of the physiopathology of TCL and they provide a potential molecular target for its treatment.

Subclinical hypothyroidism is associated with increased risk for cancer mortality in adult Taiwanese-a 10 years population-based cohort

BACKGROUND

The association between subclinical hypothyroidism (SCH) and cancer mortality is seldom discussed.

METHODS

A total of 115,746 participants without thyroid disease history, aged 20 and above, were recruited from four nationwide health screening centers in Taiwan from 1998 to 1999. SCH was defined as a serum thyroid-stimulating hormone (TSH) level of 5.0-19.96 mIU/L with normal total thyroxine concentrations. Euthyroidism was defined as a serum TSH level of 0.47-4.9 mIU/L. Cox proportional hazards regression analyses were used to estimate the relative risks (RRs) of death from cancer for adults with SCH during a 10-year follow-up period.

RESULTS

Among 115,746 adults, 1,841 had SCH (1.6%) and 113,905 (98.4%) had euthyroidism. There were 1,532 cancer deaths during the 1,034,082 person-years follow-up period. Adjusted for age, gender, body mass index, diabetes, hypertension, dyslipidemia, smoking, alcohol drinking, betel nut chewing, physical activity, income, and education level, the RRs (95% confidence interval) of cancer deaths among subjects with SCH versus euthyroid subjects were 1.51 (1.06 to 2.15). Cancer site analysis revealed a significant increased risk of bone, skin and breast cancer among SCH subjects (RR 2.79, (1.01, 7.70)). The risks of total cancer deaths were more prominent in the aged (RR 1.71, (1.02 to 2.87)), in females (RR 1.69 (1.08 to 2.65)), and in heavy smokers (RR 2.24, (1.19 to 4.21)).

CONCLUSIONS

Subjects with SCH had a significantly increased risk for cancer mortality among adult Taiwanese. This is the first report to demonstrate the association between SCH and cancer mortality.

Impact of comorbidities and use of common medications on cancer and non-cancer specific survival in esophageal carcinoma

BACKGROUND

Chronic comorbidities and some of the commonly-used medications are thought to affect cancer patients' outcomes, but their relative impact on esophageal carcinoma (EC) has not been well studied. The purpose of the study was to identify the chronic comorbidities and/or commonly-used medications that impact EC patient survival.

METHODS

A total of 1174 EC patients treated with chemoradiotherapy (CRT) with or without surgery in one institution from 1998 to 2012 were retrospectively included. Seven kinds of frequently occurring chronic comorbidities and 18 types of regularly-taken medications were obtained from medical records. Since it is expected prognostic factors have different effects between surgery patients and non-surgery patients, the impact value of all variables and the corresponding interactions with surgery on survival were evaluated in Cox proportional hazards regression model. Overall mortality, EC-specific mortality and non EC-specific mortality were endpoints.

RESULTS

We found that atrial fibrillation was the only comorbidity that showed a significant impact on non-EC specific survival for all patients (HR 1.72, P = 0.03), whereas hypothyroidism was the only comorbidity that was evaluated as an independent predictive factor for overall survival (OS) (HR 0.59, P = 0.02) and EC-specific survival (HR 0.62, P = 0.05), but this association was seen only in the non-surgical patients. No other medications were found to have a significant impact for OS, EC-specific survival or non-EC specific survival in multivariable analysis.

CONCLUSIONS

Our data indicate that certain comorbidities rather than medication use affect EC-specific survival or non EC-specific survival in EC patients treated with CRT with or without surgery. Comorbidity information may better guide individual treatment in EC.

Thyroid function alters during neoadjuvant chemotherapy in breast cancer patients: results from the NEOZOTAC trial (BOOG 2010-01)

This side study investigated the effect of chemotherapy on thyroid function and the extent to which it can predict pathological complete response (pCR) in patients with early breast cancer taking part in NEOZOTAC phase III trial, randomizing between neoadjuvant chemotherapy with or without additional zoledronic acid. Moreover, we examined the impact of thyroid function on toxicity. Serum samples of 38 patients were available for analyses. Free thyroxin (fT4) and thyroid stimulating hormone (TSH) levels were compared between baseline and before the 6th cycle and between subjects with and without pCR. The relation between toxicity and the variation in fT4 and TSH levels during chemotherapy was tested. Samples at baseline and before the 6th cycle were available for 31 and 21 patients, respectively. The mean baseline fT4 level was 16.0 pmol/L and TSH level 1.11 mU/L, and these did not differ between both arms at each time point. During six cycles of chemotherapy, fT4 levels decreased (p = 0.0001), and TSH levels increased significantly (p = 0.019). Interestingly, the decrease of fT4 was significantly greater in patients without nausea, vomiting, or neuropathy, than in patients with those side effects (p = 0.037, p = 0.043, and p = 0.050, respectively). Baseline TSH levels tended to be higher in patients with pCR (p = 0.035 univariate analysis and p = 0.074 multivariate analysis). Chemotherapy blunts thyroid function, which was associated with less side effects. These data urge further evaluation of the effects of thyroid function on toxicity and outcome of breast cancer therapy.

Recurrence of differentiated thyroid carcinoma during full TSH suppression: is the tumor now thyroid hormone dependent?

Well-standardized primary treatment and long-term management of differentiated thyroid carcinoma (DTC) include lowering or suppression of host thyrotropin (TSH) with exogenous L-thyroxine (T₄). This treatment recognizes the trophic action of TSH on DTC cells. Suppression of endogenous TSH with T₄ is continued in recurrent disease. However, T₄ can induce proliferation of follicular and papillary thyroid carcinoma cell lines and of other human carcinoma cells. The proliferative mechanism is initiated at a cell surface receptor for T₄ on integrin αvβ3, a receptor by which the hormone also inhibits p53-dependent apoptosis in tumor cells. In recurrent DTC with satisfactory suppression of endogenous TSH, we discuss here the possibility that the tumor is no longer TSH dependent and that T₄ has become a critical growth factor for the cancer.

Nanotetrac targets integrin αvβ3 on tumor cells to disorder cell defense pathways and block angiogenesis

The extracellular domain of integrin αvβ3 contains a receptor for thyroid hormone and hormone analogs. The integrin is amply expressed by tumor cells and dividing blood vessel cells. The proangiogenic properties of thyroid hormone and the capacity of the hormone to promote cancer cell proliferation are functions regulated nongenomically by the hormone receptor on αvβ3. An L-thyroxine (T4) analog, tetraiodothyroacetic acid (tetrac), blocks binding of T4 and 3,5,3'-triiodo-L-thyronine (T3) by αvβ3 and inhibits angiogenic activity of thyroid hormone. Covalently bound to a 200 nm nanoparticle that limits its activity to the cell exterior, tetrac reformulated as Nanotetrac has additional effects mediated by αvβ3 beyond the inhibition of binding of T4 and T3 to the integrin. These actions of Nanotetrac include disruption of transcription of cell survival pathway genes, promotion of apoptosis by multiple mechanisms, and interruption of repair of double-strand deoxyribonucleic acid breaks caused by irradiation of cells. Among the genes whose expression is suppressed by Nanotetrac are EGFR, VEGFA, multiple cyclins, catenins, and multiple cytokines. Nanotetrac has been effective as a chemotherapeutic agent in preclinical studies of human cancer xenografts. The low concentrations of αvβ3 on the surface of quiescent nonmalignant cells have minimized toxicity of the agent in animal studies.

Dose-volumetric parameters for predicting hypothyroidism after radiotherapy for head and neck cancer

OBJECTIVE

To investigate predictors affecting the development of hypothyroidism after radiotherapy for head and neck cancer, focusing on radiation dose-volumetric parameters, and to determine the appropriate radiation dose-volumetric threshold of radiation-induced hypothyroidism.

METHODS

A total of 114 patients with head and neck cancer whose radiotherapy fields included the thyroid gland were analysed. The purpose of the radiotherapy was either definitive (n = 81) or post-operative (n = 33). Thyroid function was monitored before starting radiotherapy and after completion of radiotherapy at 1 month, 6 months, 1 year and 2 years. A diagnosis of hypothyroidism was based on a thyroid stimulating hormone value greater than the maximum value of laboratory range, regardless of symptoms. In all patients, dose volumetric parameters were analysed.

RESULTS

Median follow-up duration was 25 months (range; 6-38). Forty-six percent of the patients were diagnosed as hypothyroidism after a median time of 8 months (range; 1-24). There were no significant differences in the distribution of age, gender, surgery, radiotherapy technique and chemotherapy between the euthyroid group and the hypothyroid group. In univariate analysis, the mean dose and V35-V50 results were significantly associated with hypothyroidism. The V45 is the only variable that independently contributes to the prediction of hypothyroidism in multivariate analysis and V45 of 50% was a threshold value. If V45 was <50%, the cumulative incidence of hypothyroidism at 1 year was 22.8%, whereas the incidence was 56.1% if V45 was ≥50% (P = 0.034).

CONCLUSIONS

The V45 may predict risk of developing hypothyroidism after radiotherapy for head and neck cancer, and a V45 of 50% can be a useful dose-volumetric threshold of radiation-induced hypothyroidism.

Cancer Cell Gene Expression Modulated from Plasma Membrane Integrin αvβ3 by Thyroid Hormone and Nanoparticulate Tetrac

Integrin αvβ3 is generously expressed by cancer cells and rapidly dividing endothelial cells. The principal ligands of the integrin are extracellular matrix proteins, but we have described a cell surface small molecule receptor on αvβ3 that specifically binds thyroid hormone and thyroid hormone analogs. From this receptor, thyroid hormone (l-thyroxine, T4; 3,5,3'-triiodo-l-thyronine, T3) and tetraiodothyroacetic acid (tetrac) regulate expression of specific genes by a mechanism that is initiated non-genomically. At the integrin, T4 and T3 at physiological concentrations are pro-angiogenic by multiple mechanisms that include gene expression, and T4 supports tumor cell proliferation. Tetrac blocks the transcriptional activities directed by T4 and T3 at αvβ3, but, independently of T4 and T3, tetrac modulates transcription of cancer cell genes that are important to cell survival pathways, control of the cell cycle, angiogenesis, apoptosis, cell export of chemotherapeutic agents, and repair of double-strand DNA breaks. We have covalently bound tetrac to a 200 nm biodegradable nanoparticle that prohibits cell entry of tetrac and limits its action to the hormone receptor on the extracellular domain of plasma membrane αvβ3. This reformulation has greater potency than unmodified tetrac at the integrin and affects a broader range of cancer-relevant genes. In addition to these actions on intra-cellular kinase-mediated regulation of gene expression, hormone analogs at αvβ3 have additional effects on intra-cellular protein-trafficking (cytosol compartment to nucleus), nucleoprotein phosphorylation, and generation of nuclear coactivator complexes that are relevant to traditional genomic actions of T3. Thus, previously unrecognized cell surface-initiated actions of thyroid hormone and tetrac formulations at αvβ3 offer opportunities to regulate angiogenesis and multiple aspects of cancer cell behavior.

Thyroid dysfunction as an unintended side effect of anticancer drugs

BACKGROUND

Several of the currently used anticancer drugs may variably affect thyroid function, with impairment ranging from modified total but not free concentration of thyroid hormones to overt thyroid disease.

SUMMARY

Cytotoxic agents seem to alter thyroid function in a relatively small proportion of adult patients. Anticancer hormone drugs may mainly alter serum levels of thyroid hormone-binding proteins without clinically relevant thyroid dysfunction. Old immunomodulating drugs, such as interferon-α and interleukin-2, are known to induce variably high incidence of autoimmune thyroid dysfunction. Newer immune checkpoint inhibitors, such as anti-CTLA4 monoclonal antibodies, are responsible for a relatively low incidence of thyroiditis and may induce secondary hypothyroidism resulting from hypophysitis. Central hypothyroidism is a well-recognized side effect of bexarotene. Despite their inherent selectivity, tyrosine kinase inhibitors may cause high rates of thyroid dysfunction. Notably, thyroid toxicity seems to be restricted to tyrosine kinase inhibitors targeting key kinase-receptors in angiogenic pathways, but not other kinase-receptors (e.g., epidermal growth factor receptors family or c-KIT). In addition, a number of these agents may also increase the levothyroxine requirement in thyroidectomized patients.

CONCLUSIONS

The pathophysiology of thyroid toxicity induced by many anticancer agents is not fully clarified and for others it remains speculative. Thyroid dysfunction induced by anticancer agents is generally manageable and dose reduction or discontinuation of these agents is not required. The prognostic relevance of thyroid autoimmunity, overt and subclinical hypothyroidism induced by anticancer drugs, the value of thyroid hormone replacement in individuals with abnormal thyrotropin following anticancer systemic therapy, and the correct timing of replacement therapy in cancer patients need to be defined more accurately in well-powered prospective clinical trials.

Thyroid dysfunction and tyrosine kinase inhibitors in renal cell carcinoma

The most recent World Health Organization classification of renal neoplasms encompassed nearly 50 distinctive renal neoplasms. Different histological subtypes have different clinical outcomes and show different responses to therapy. Overall, the incidence of kidney cancer has increased worldwide in the last years. Although the most common type of kidney cancer is localized renal cell carcinoma (RCC), with a 5-year survival rate of 85%, about one third of patients present advanced or metastatic disease at diagnosis, with a 5-year survival rate of only 10%. Multi-targeted receptor tyrosine kinase inhibitors (TKIs, sunitinib and sorafenib), the anti-VEGF MAB bevacizumab in association with interferon-α, and the mTOR inhibitors are now approved for the treatment of mRCC. Recently, the novel agents pazopanib and axitinib have also demonstrated efficacy in mRCC patients. Several recent retrospective and prospective trials have suggested that some of their adverse events, such as hypertension, hypothyroidism, and hand foot syndrome (HFS) may act as potential biomarkers of response and efficacy of treatment. In this review, we analyzed the studies that have suggested a relationship between hypothyroidism onset and a better outcome of mRCC patients treated with TKIs. The biological mechanisms suggesting and explaining this correlation are not well known and different speculative theories have been considered in order to investigate the clinical link between hypothyroidism occurrence and the prolonged therapy with TKIs in solid tumors. Furthermore, the management of this unexplained side effect is very important to maximize the efficacy of therapy in mRCC patients because there is a clear and consistent relationship between drug dose and efficacy of treatment. Certainly, other studies are needed to clarify whether a better outcome is associated with hypothyroidism induced to TKIs in patients with mRCC.

Does thyroid-stimulating hormone influence the prognosis of patients with endometrial cancer? A multicentre trial

Background:

Thyroid function has been suggested to interfere with tumour biology and prognosis in different cancers. The present study was performed to investigate the impact of pre-therapeutic serum thyroid-stimulating hormone (TSH) levels on the prognosis of patients with endometrial cancer.

Methods:

Pre-therapeutic serum TSH was investigated in 199 patients with endometrial cancer. After stratification in TSH risk groups, univariate and multivariable survival analyses were performed.

Results:

Elevated TSH was independently associated with poor disease-specific survival in univariate/multivariable survival analyses (P=0.01 and P=0.03, respectively).

Conclusion:

Thyroid-stimulating hormone may serve as a novel and independent prognostic parameter for disease-specific survival in patients with endometrial cancer.

TSH receptor antibodies have predictive value for breast cancer - retrospective analysis

Background

Associations between breast cancer and thyroid disorders are reported in numerous studies. Relationships between thyroperoxidase antibodies (TPOAb), thyroglobulin antibodies (TgAb) and breast cancer have been previously demonstrated. However, no analysis has been performed concerning an association between thyrotropin (TSH) receptor antibodies (TSHRAb) and breast cancer. The aim of the study was to evaluate the prevalence of breast cancer or benign breast tumors in patients with Graves’ disease and to analyze a possible relationship between Graves’ disease and these two groups of breast diseases with emphasis to epidemiology and laboratory findings.

Patients and methods

Clinical and laboratory details of 2003 women hospitalized for endocrine disorders were retrospectively analyzed, using an unpaired Student’s t-test, logistic regression analysis, χ² test of independence or the two-sided ratio comparison test.

Results

The coexistence of Graves’ disease and breast cancer was statistically significant. We observed TSHRAb and TgAb more frequently in patients with breast cancer. We found that TSHRAb is the only variable possessing predictive value for breast cancer.

Conclusions

The strong relationship between Graves’ disease and breast cancer is proposed. We suggest that TSHRAb could be described as a positive determinant of breast cancer. The present data call attention to the usefulness of screening for breast cancer in long-term follow-up of patients with autoimmune thyroid disorders, especially of those with Graves’ disease. Similarly, screening for autoimmune thyroid disorders should be performed in patients with nodular breast disease. Additionally, the article draws ideas for further research in order to develop targeted treatment for more successful outcome in patients with breast cancer.

Thyroid hormone, thyroid hormone receptors, and cancer: a clinical perspective

Thyroid hormones (THs) may play a role in diseases other than hyper- and hypothyroidism. Several lines of evidence suggest tumor-promoting effects of TH and TH receptors. They are possibly mediated by phosphatidylinositol-3-kinase and MAPK and involve among others stimulation of angiogenesis via αvβ3. Thus, an increased risk for colon, lung, prostate, and breast cancer with lower TSH has been demonstrated in epidemiological studies, even suggesting a TH dose effect on cancer occurrence. Furthermore, higher TH levels were associated with an advanced clinical stage of breast and prostate cancer. In rodent models, TH stimulated growth and metastasis of tumor transplants, whereas hypothyroidism had opposite effects. In clinical studies of glioblastoma and head and neck cancer, hypothyroid patients showed longer survival than euthyroid patients. Also, patients with renal cell cancer that were treated with the tyrosine kinase inhibitor sunitinib and developed hypothyroidism in due course showed significantly longer survival than patients that remained euthyroid. Development of hypothyroidism was an independent predictor for survival in two studies. Yet, it is still possible that hypothyroidism is only a surrogate marker for treatment efficacy and does not positively influence treatment outcome by itself. Future cancer treatment studies, especially with substances that can induce hypothyroidism, should therefore be designed in a way that allows for an analysis of thyroid function status and its contribution on treatment outcome.

Extreme hypothyroidism associated with sunitinib treatment for metastatic renal cancer

Although thyroid abnormalities are reported with the use of tyrosine kinase inhibitors, patients rarely require replacement therapy. The initial multicentre studies of sunitinib for metastatic renal cancer did not report hypothyroidism in fatigued patients, and thyroid tests were not routinely monitored. More recent studies, however, suggest that up to 70% of patients develop thyroid test abnormalities during treatment with sunitinib. Despite these concerns, the clinical relevance of sunitinib-induced hypothyroidism is uncertain since thyroid gland recovery is the norm in most patients. We report a case of a patient with metastatic papillary renal cell cancer on combination anti-angiogenic therapy with sunitinib, who developed unusually high thyroid stimulating hormone levels and severe symptoms despite receiving L-thyroxine. Our case also illustrates the complexity of managing sunitinib-associated thyroid dysfunction, which may be accompanied by transient thyroiditis, hyperthyroidism, and profound hypothyroidism.

Does sunitinib-induced hypothyroidism play a role in the activity of sunitinib in metastatic renal cell carcinoma?

BACKGROUND

The objective of this study was to evaluate if hypothyroidism developing during sunitib therapy in patients with metastatic renal cell carcinoma (mRCC) is associated with a better outcome.

METHODS

Thirty-one consecutive patients with clear cell mRCC were retrospectively analyzed. Thyroid function was assessed prior to therapy, every 6 weeks during the first 6 months and every 2-4 months thereafter. Hypothyroidism was considered present if thyroid-stimulating hormone (TSH) exceeded the upper normal limit (UNL) with normal triiodothyronine (T3) and thyroxine (T4).

RESULTS

Hypothyroidism occurred in 16 patients (52%) within 3 months (range 0.7-22.9) of treatment initiation. Thyroid replacement corrected TSH below the UNL in 10 patients (63%). The distribution according to Motzer prognostic criteria revealed good prognosis in 16 patients (52%), intermediate in 9 (29%) and poor in 6 (19%). The hypothyroid patients tended to have longer progression-free survival (PFS; median 12.2 vs. 9.4 months; p = 0.234) and longer survival (median 22.4 vs. 13.9 months; p = 0.234) than the euthyroid patients. Clinical benefits were similar in both groups.

CONCLUSIONS

Hypothyroidism that develops in mRCC patients treated with sunitinib is associated with a trend toward prolonged PFS and survival, with a similar clinical benefit rate.

Therapy management with sunitinib in patients with metastatic renal cell carcinoma: key concepts and the impact of clinical biomarkers

Targeted agents have improved prognosis for patients with metastatic renal cell carcinoma (mRCC), and they are changing therapeutic expectations with respect to long-term clinical outcomes for these patients. However, in order to obtain the maximum clinical benefit from targeted agents, effective therapy management is essential and includes optimization of dosing and treatment duration, as well as adequate side-effect management. Sunitinib has demonstrated efficacy for the treatment of patients with mRCC and is a reference standard of care for first-line therapy. However, in clinical practice, it is difficult to determine the best treatment strategy with targeted agents due to long-term tolerability and the development of resistance. An individualized therapeutic strategy in RCC requires a comprehensive understanding of the biology of response and resistance to targeted therapy. Here we review the clinical data regarding the efficacy and safety for sunitinib and highlight the importance of therapy management, as well as the potential use of clinical biomarkers in order to maximize the clinical benefit from sunitinib treatment in patients with mRCC.

Could thyroid dysfunction influence outcome in sunitinib-treated metastatic renal cell carcinoma?

BACKGROUND

Sunitinib is a standard of care for metastatic renal cell carcinoma (mRCC). Hypothyroidism is frequently observed under sunitinib therapy. This study was conducted to prospectively determine the correlation between thyroid function and progression-free survival (PFS) in this population.

PATIENTS AND METHODS

One hundred and eleven mRCC patients treated with sunitinib were evaluated for serum thyroid-stimulating hormone (TSH) and T4 levels before treatment and every 6 weeks during treatment. Survival was analysed according to a landmark method with a cut-off of 6 months, excluding early progressive or early-censored patients.

RESULTS

Out of the 102 patients with normal baseline thyroid function, 53% developed thyroid dysfunction, including 95% hypothyroidisms out of which 90.9% received L-thyroxine replacement. Median time to TSH alteration was 5.4 months. Median PFS was 11.7 months for the entire population. Median PFS was not different between the groups with abnormal or normal thyroid function after 6 months of treatment (18.9 and 15.9 months, respectively, log-rank P = 0.94, hazard ratio = 1.02, 95% confidence interval = 0.54-1.93). There was no difference even after adjustment for Memorial Sloan-Kettering Cancer Centre classification and therapy line.

CONCLUSIONS

Abnormal thyroid function with hormonal substitution did not increase survival in our population, independent of initial prognosis and previous treatments. Larger comparative studies are deserved to validate these conclusions.

Toxicity as a biomarker of efficacy of molecular targeted therapies: focus on EGFR and VEGF inhibiting anticancer drugs

In addition to being present in tumor cells, many targets of signal transduction inhibitors are also found in normal tissue. Side effects attributable to the mechanism of action of molecular targeted agents thus represent "on-target" modulation in normal tissues. These mechanism-based toxicities can be pharmacodynamic effects of pathway inhibition and, in tumors depending on the inhibited pathway for proliferation, might be biomarkers of efficacy. The development of rash with tyrosine kinase inhibitors or monoclonal antibodies targeting the epidermal growth factor receptor is associated with superior outcomes in lung, head and neck, colorectal, and pancreatic cancer studies. Correlated with superior efficacy in retrospective analyses of large studies in advanced colorectal, breast, and renal cell carcinoma, arterial hypertension as an adverse event of antiangiogenic agents may also be a marker of effective target inhibition. An association between hypothyroidism and the activity of multitargeted tyrosine kinase inhibitors has been identified in renal cell carcinoma patients. Tumor growth addiction to the specific pathway that is effectively targeted may be the link between a mechanism-based toxicity and efficacy. The biological basis for this correlation can be pharmacological, with higher drug exposure being associated with greater toxicity and antitumor activity, and can also be genetic, because single nucleotide polymorphisms play an important role in drug pharmacokinetic and pharmacodynamic processes. Investigators have proposed that interpatient differences and associated toxicities can be exploited for dose selection and titration, and clinical trials are currently exploring intrapatient "dosing-to-toxicity" strategies. Ultimately, the predictive value of a side effect of molecular targeted therapies requires validation in prospective trials.

Thyroid dysfunction from antineoplastic agents

Unlike cytotoxic agents that indiscriminately affect rapidly dividing cells, newer antineoplastic agents such as targeted therapies and immunotherapies are associated with thyroid dysfunction. These include tyrosine kinase inhibitors, bexarotene, radioiodine-based cancer therapies, denileukin diftitox, alemtuzumab, interferon-α, interleukin-2, ipilimumab, tremelimumab, thalidomide, and lenalidomide. Primary hypothyroidism is the most common side effect, although thyrotoxicosis and effects on thyroid-stimulating hormone secretion and thyroid hormone metabolism have also been described. Most agents cause thyroid dysfunction in 20%-50% of patients, although some have even higher rates. Despite this, physicians may overlook drug-induced thyroid dysfunction because of the complexity of the clinical picture in the cancer patient. Symptoms of hypothyroidism, such as fatigue, weakness, depression, memory loss, cold intolerance, and cardiovascular effects, may be incorrectly attributed to the primary disease or to the antineoplastic agent. Underdiagnosis of thyroid dysfunction can have important consequences for cancer patient management. At a minimum, the symptoms will adversely affect the patient's quality of life. Alternatively, such symptoms can lead to dose reductions of potentially life-saving therapies. Hypothyroidism can also alter the kinetics and clearance of medications, which may lead to undesirable side effects. Thyrotoxicosis can be mistaken for sepsis or a nonendocrinologic drug side effect. In some patients, thyroid disease may indicate a higher likelihood of tumor response to the agent. Both hypothyroidism and thyrotoxicosis are easily diagnosed with inexpensive and specific tests. In many patients, particularly those with hypothyroidism, the treatment is straightforward. We therefore recommend routine testing for thyroid abnormalities in patients receiving these antineoplastic agents.

Dermatomyositis related to autoimmune thyroiditis

BACKGROUND AND OBJECTIVE

Reports on the coexistence of dermatomyositis (DM) with autoimmune thyroiditis (AIT) are very few. Our aim is to define the relationship of the two conditions, identify clinical, laboratory, electromyographic and pathologic features of coexistent DM and AIT.

METHODS

We underwent a MEDLINE search to identify relevant literature published in the past 30 years. Concurrently, we analysed retrospectively medical records of five patients diagnosed with DM and AIT from our hospital.

RESULTS

Eleven cases were included. 90.9% of patients were female with a mean (SD) age of 44.18 (13.11) years for DM at diagnosis, and 39.00 (7.81) years for AIT. AIT can precede or parallel the diagnosis of DM. The most common comorbidities included hypothyroidism (90.9%), cardiopulmonary diseases (63.7%) and overlap syndrome (27.3%), while only one case had malignancy. The most common clinical manifestations were: muscle weakness (100%), polyarthralgia (45.5%), heliotrope rash (45.5%), myalgia (36.4%), and Raynaud's phenomenon (27.3%). The abnormalities on electromyography and muscle/skin biopsy of DM related to AIT did not differ from those findings of DM, while none of these reports were normal. All patients received both the treatment of corticosteroids and levothyroxine, and only 27.3% of patients had a good prognosis.

CONCLUSION

Prevalence of cancer in coexistent DM and AIT may be very low. Also, it is reasonable to suggest that DM patients with AIT should be routinely evaluated for thyroid function and the emergence of comorbidities. Moreover, corticosteroids combined with levothyroxine may be useful for these patients as a standard treatment.

The impact of sunitinib-induced hypothyroidism on progression-free survival of metastatic renal cancer patients: a prospective single-center study

BACKGROUND

Several studies have reported unexpected rates of hypothyroidism in patients treated with sunitinib. The biochemical basis of this impairment is unknown. A relationship between hypothyroidism and improved outcome has been suggested in some cancer patients. Here we describe the incidence of newly onset hypothyroidism and its relationship with progression-free survival in metastatic renal cell carcinoma patients undergoing sunitinib treatment at our institution.

PATIENTS AND METHODS

Between July 2007 and June 2009, 22 patients received a first line sunitinib for metastatic renal cell carcinoma. Thyroid function tests were prospectively evaluated as routine laboratory assessment in every patient, at baseline and on the first and last day of every ON and OFF sunitinib period.

RESULTS

The median duration of treatment was 39.5 weeks. During sunitinib therapy, 13 patients (59.1%) showed at least one elevated TSH level. No reductions of TSH below normal ranges were observed. L-thyroxine replacement therapy was required in 2 patients. Based on thyroid function, median progression-free survival was 8.55 months for hypothyroid compared with 7.03 months for euthyroid patients (P < 0.05).

CONCLUSION

Patients administered sunitinib have an high incidence of hypothyroidism. The improved outcome of hypothyroid patients suggests an important relationship between sunitinib and this uncommon side effect.