Thyroid dysfunction in patients with childhood-onset medulloblastoma or primitive neuroectodermal tumor

Homeostatic status of thyroid hormones and brain water movement as determinant factors in biology of cerebral gliomas: a pilot study using a bioinformatics approach

Introduction

The expression and localization of the water channel transporters, aquaporins (AQPs), in the brain are substantially modified in gliomas during tumorigenesis, cell migration, edema formation, and resolution. We hypothesized that the molecular changes associated with AQP1 and AQP4 in the brain may potentially be anticancer therapeutic targets. To test this hypothesis, a bioinformatics analysis of publicly available data from international consortia was performed.

Methods

We used RNA-seq as an experimental strategy and identified the number of differential AQP1 and AQP4 transcript expressions in glioma tissue compared to normal brain tissue.

Results

AQPs genes are overexpressed in patients with glioma. Among the glioma subtypes, AQP1 and AQP4 were overexpressed in astrocytoma (low-grade glioma) and classical (high-grade glioma). Overall survival analysis demonstrated that both AQP genes can be used as prognostic factors for patients with low-grade glioma. Additionally, we observed a correlation between the expression of genes involved in the tyrosine and thyroid hormone pathways and AQPs, namely: PNMT, ALDH1A3, AOC2, HGDATP1B1, ADCY5, PLCB4, ITPR1, ATP1A3, LRP2, HDAC1, MED24, MTOR, and ACTB1 (Spearman's coefficient = geq 0.20 and p-value = ≤ 0.05).

Conclusion

Our findings indicate that the thyroid hormone pathways and AQPs 1 and 4 are potential targets for new anti-tumor drugs and therapeutic biomarkers for malignant gliomas.

Characteristics and clinical course of thyroid abnormalities arisen in long term survivors of childhood cancer

BACKGROUND

Thyroid abnormality is a common late effect seen in childhood cancer survivors (CCSs). We analyzed the prevalence and risk factors of thyroid abnormalities based on diagnoses and treatment modalities in CCSs.

METHODS

The medical records of 257 CCSs who were diagnosed with cancer less than 20 year of age were retrospectively reviewed. The median age was 11.8 years (0.1-19.8). The median follow-up period after completion of therapy was 9.6 years (5.0-19.5).

RESULTS

Of 257 subjects, thyroid abnormalities were identified in 107 (41.6%). Sixty-five out of 257 (25.3%) had subclinical hypothyroidism, and 16 (6.2%) developed central hypothyroidism. Five CCSs (1.9%) had primary overt hypothyroidism. Five (1.9%) and 6 (2.3%) CCSs were diagnosed with autoimmune thyroiditis and thyroid cancer, respectively. Among the different diagnostic groups, thyroid abnormalities were frequent in the brain tumor or Hodgkin disease or nasopharyngeal cancer groups. CCSs who received irradiation directly or near hypothalamus-pituitary-thyroid (HPT) axis had more thyroid abnormalities compared to the rest CCSs (P < 0.0001). CCSs who were treated with SCT had an increased prevalence of thyroid abnormalities (60.5%) compared to the other CCSs (37.9%) (P = 0.0069). Forty-five (42%) of 107 subjects with thyroid abnormalities had normalized thyroid hormone levels at the last follow-up. Irradiation directly or near HPT axis were thought to be a predicting factor of persistent subclinical hypothyroidism.

CONCLUSIONS

Subclinical hypothyroidism was common in CCSs. CCSs with irradiation directly or near HPT axis were at risk for persistent thyroid dysfunction.

Endocrinopathy After Treatment for Medulloblastoma: Results From the SJMB03 Trial of Risk-Adapted Radiation Therapy

PURPOSE

The objective of this study was to estimate the cumulative incidence of endocrinopathy in pediatric patients treated for medulloblastoma with surgery, risk-adapted photon craniospinal irradiation, and dose-intensive chemotherapy.

METHODS AND MATERIALS

Children and adolescents (n = 156) treated between 2003 and 2013 were evaluated for evidence of endocrinopathy. Clinical information and mean radiation dose to hypothalamus and thyroid were calculated and used to estimate cumulative incidence of growth hormone deficiency, hypothyroidism, adrenal insufficiency, hypogonadism, and precocious puberty.

RESULTS

The 5-year cumulative incidences were estimated for growth hormone deficiency, 68.9% (60.9%, 75.6%); hypothyroidism, 48.4% (95% confidence interval (CI), 40.2%-56.1%); adrenal insufficiency, 13.0% (95% CI, 8.3%-18.9%); hypogonadism, 33.9% (95% CI, 25.2%-42.7%); and precocious puberty, 2.0% (95% CI, 0.6%-5.4%). Growth hormone deficiency was associated with increased hypothalamus dose (hazard ratio [HR], 1.035; 95% CI, 1.010-1.061; P = .0055) in average-risk patients and cerebrospinal fluid shunt (HR, 2.532; 95% CI, 1.325-4.838; P = .0049) in high-risk patients. In average-risk patients, hypothyroidism was associated with younger age (HR, 0.902; 95% CI, 0.842-0.973; P = .0070), hypothalamus dose (HR, 1.039; 95% CI, 1.004-1.075; P = .0273), and thyroid dose (HR, 1.070; 95% CI, 1.008-1.136; P = .0263). In high-risk patients, hypothyroidism was associated with increased hypothalamus dose (HR, 1.068; 95% CI, 0.995-1.147; P = .0671) and thyroid dose (HR, 1.050; 95% CI, 1.000-1.104; P = .0515). Adrenal insufficiency was associated with increased hypothalamus dose (HR, 1.112; 95% CI, 1.058-1.170; P < .0001). Growth hormone deficiency incidence was higher when comparing patients treated with cerebrospinal fluid shunt versus those not having a shunt/extraventricular drain placed during initial surgery (HR, 1.712; 95% CI, 1.109-2.643).

CONCLUSIONS

Incidence and time to onset of clinically significant endocrinopathy after photon craniospinal irradiation for pediatric medulloblastoma is influenced by radiation dose to target organs and patient age at time of treatment. Advanced radiation therapy methods and dose-reduction strategies are needed to reduce the incidence of endocrinopathy.

Predictive factors for thyroid complications after radiation therapy-data from a cohort of cancer patients closely followed since they were irradiated

INTRODUCTION

Cancer survivors are at an increased risk of adverse outcomes, including thyroid neoplasms, given the high radiosensitivity of this gland. The aim of this study is to assess the incidence and timeframe of thyroid complications in cancer patients, followed systematically since their radiation therapy, and to identify risk factors for the development of hypothyroidism and thyroid cancer.

METHODS

We performed a retrospective study, including 282 subjects, who received neck, craniospinal, or total body irradiation (TBI). Patients were grouped into four primary diagnostic clusters: leukaemia, Hodgkin's disease, central nervous system, and head and neck tumours.

RESULTS

Hypothyroidism was observed in 56.7% of patients, on average 6.8 ± 5.9 years after the treatment. Neck and craniospinal irradiation presented a 3.5-fold increased risk for the development of hypothyroidism compared to TBI. Papillary thyroid cancer was diagnosed in 8.5% of the patients, on average, 18.5 ± 4.9 years after radiotherapy (RT). Female gender, younger age, and lower irradiation doses were independently associated with thyroid cancer development.

CONCLUSION

Our study provides useful information about the risk of hypothyroidism and thyroid cancer after RT, as it was performed in a cohort of patients closely followed since the oncological therapies, and, thus, may give new insights into the follow-up management of these patients.

Thyroid Sequelae of Pediatric Cancer Therapy

The hypothalamic-pituitary-thyroid axis is a common site of unintended, acquired disease either during or after the treatment of cancer. Children treated with external radiation therapy are at the highest risk for developing a thyroid-related late effect, but thyroid dysfunction and second primary thyroid neoplasms can also occur after treatment with radiopharmaceutical agents such as 131I-metaiodobenzylguanidine. Increasingly recognized is the development of early thyroid dysfunction as an off-target consequence of the more novel cancer therapeutics such as the tyrosine kinase inhibitors and immune checkpoint inhibitors. Thyroid sequelae resulting from irradiation may manifest only after years to decades of follow-up, and their resultant clinical symptoms may be indolent and non-specific. Therefore, lifelong monitoring of the childhood cancer survivor at risk for thyroid disease is paramount. In this comprehensive review, the myriad thyroid adverse effects resulting from pediatric cancer treatment are discussed and an overview of screening and treatment of these thyroid sequelae provided.