GONADAL EFFECT OF RADIATION FROM131I IN MALE PATIENTS WITH THYROID CARCINOMA

Multidisciplinary consensus on the criteria for fertility preservation in cancer patients

Infertility is one of the main sequelae of cancer and its treatment in both children and adults of reproductive age. It is, therefore, essential that oncologists and haematologists provide adequate information about the risk of infertility and the possibilities for its preservation before starting treatment. Although many international clinical guidelines address this issue, this document is the first Spanish multidisciplinary guideline in paediatric and adult oncological patients. Experts from the Spanish Society of Medical Oncology, the Spanish Fertility Society, the Spanish Society of Haematology and Haemotherapy, the Spanish Society of Paediatric Haematology and Oncology and the Spanish Society of Radiation Oncology have collaborated to develop a multidisciplinary consensus.

Genetic Landscape of Papillary Thyroid Carcinoma and Nuclear Architecture: An Overview Comparing Pediatric and Adult Populations

Thyroid cancer is a rare malignancy in the pediatric population that is highly associated with disease aggressiveness and advanced disease stages when compared to adult population. The biological and molecular features underlying pediatric and adult thyroid cancer pathogenesis could be responsible for differences in the clinical presentation and prognosis. Despite this, the clinical assessment and treatments used in pediatric thyroid cancer are the same as those implemented for adults and specific personalized target treatments are not used in clinical practice. In this review, we focus on papillary thyroid carcinoma (PTC), which represents 80-90% of all differentiated thyroid carcinomas. PTC has a high rate of gene fusions and mutations, which can influence the histologic subtypes in both children and adults. This review also highlights telomere-related genomic instability and changes in nuclear organization as novel biomarkers for thyroid cancers.

Papillary thyroid carcinoma presenting as miliary nodules on chest roentgenogram in the paediatric setting: A case report

INTRODUCTION

Papillary thyroid carcinoma (PTC) is the most common carcinoma to occur in childhood with a peak incidence between 11-17 years, and typically presents with advanced locoregional disease. Pulmonary metastases are seen in up to 46% of cases and should enter the differential diagnosis of miliary nodules seen on chest roentgenogram, even in regions where tuberculosis is endemic.

PRESENTATION OF CASE

An 11-year-old male presented with a short history of cough, shortness of breath and constitutional symptoms. Examination revealed cervical lymphadenopathy and diffuse bilateral nodular infiltrates on the chest roentgenogram. Investigation for Mycobacterium tuberculosis was negative and this initiated biopsy of a cervical lymph node. Histopathological examination revealed metastatic PTC. Ultrasonography and magnetic resonance imaging (MRI) were performed for preoperative staging. The patient subsequently underwent total thyroidectomy with selective neck dissection.

DISCUSSION

There are several potential causes when dealing with miliary nodules on chest roentgenogram. Thorough interrogation of the clinical, radiological, pathological and microbiological data is required to arrive at the correct diagnosis. Postoperative adjuvant therapy with radioactive iodine is recommended in children with metastatic disease, but this should be restricted preferably to a single dose to avoid the complication of pulmonary fibrosis.

CONCLUSION

This case highlights the differential diagnostic considerations of a patient presenting with constitutional symptoms and a miliary pattern on chest roentgenogram. Carcinomas are uncommon in children but should not be forgotten.

Initial treatment patterns in younger adult patients with differentiated thyroid cancer in California

BACKGROUND

Differentiated thyroid cancer (DTC) is among the most common malignancies in the adolescent and young adult (age 15-39 years) population, and its incidence is rising. Younger age (<45 years) is an important prognostic indicator and is incorporated into the TNM classification system. This study hypothesized that this would result in distinct treatment patterns for younger and older patients.

METHODS

Using the California Cancer Registry, 24,362 patients with DTC from 2004 to 2011 were identified, and they were divided into younger (<45 years) and older (≥45 years) cohorts. Demographic and clinical variables were tabulated and then compared using chi-square tests. Treatment variables included total or near total thyroidectomy, other types of thyroid surgery, and the administration of radioiodine as part of the initial treatment. Multivariable logistic regression was used to identify independent predictors of treatment administered.

RESULTS

Younger patients were more likely to be Hispanic (32.5% vs. 21.2%) and female (82.7% vs. 74.7%), and to have papillary carcinoma (92.9% vs. 90.9%) and lymph node involvement (32.8% vs. 19.7%; p<0.0001). On multivariable analysis, younger patients (OR 1.20 [CI 1.11-1.30]), higher T-stage tumors, higher socioeconomic status (SES), and papillary carcinoma were predictors of undergoing total thyroidectomy versus less than total thyroid surgery. After adjustment, predictors of radioiodine administration included younger age (OR 1.12 [CI 1.05-1.18]), higher SES, total thyroidectomy, higher T stage, and lymph node positivity.

CONCLUSIONS

Younger patients with DTC in California are more likely to be female and Hispanic with papillary histology. After adjustment for disease and demographic characteristics, younger patients are more likely to undergo total thyroidectomy as their initial surgery and are more likely to receive radioiodine. Given their excellent prognosis and the potential for adverse sequelae from initial treatment for DTC, these findings warrant consideration when managing younger patients with DTC.

Paracrine interactions of thyroid hormones and thyroid stimulation hormone in the female reproductive tract have an impact on female fertility

Thyroid disease often causes menstrual disturbances and infertility problems. Thyroid hormone (TH) acts through its receptors, transcription factors present in most cell types in the body. Thyroid stimulating hormone (TSH) stimulates TH synthesis in the thyroid gland, but seems to have other functions as well in the female reproductive tract. The receptors of both TH and TSH increase in the receptive endometrium, suggesting that they are important for implantation, possible by influencing inflammatory mediators such as leukemia inhibitory factor. The roles of these receptors in the ovary need further studies. However, it is likely that the thyroid system is important for both follicular and embryo development. The association between thyroid disease and infertility indicate that TH and TSH affect the endometrium and ovary on the paracrine level.

The treatment of differentiated thyroid cancer in children: emphasis on surgical approach and radioactive iodine therapy

Pediatric thyroid cancer is a rare disease with an excellent prognosis. Compared with adults, epithelial-derived differentiated thyroid cancer (DTC), which includes papillary and follicular thyroid cancer, presents at more advanced stages in children and is associated with higher rates of recurrence. Because of its uncommon occurrence, randomized trials have not been applied to test best-care options in children. Even in adults that have a 10-fold or higher incidence of thyroid cancer than children, few prospective trials have been executed to compare treatment approaches. We recognize that treatment recommendations have changed over the past few decades and will continue to do so. Respecting the aggressiveness of pediatric thyroid cancer, high recurrence rates, and the problems associated with decades of long-term follow-up, a premium should be placed on treatments that minimize risk of recurrence and the adverse effects of treatments and facilitate follow-up. We recommend that total thyroidectomy and central compartment lymph node dissection is the surgical procedure of choice for children with DTC if it can be performed by a high-volume thyroid surgeon. We recommend radioactive iodine therapy for remnant ablation or residual disease for most children with DTC. We recommend long-term follow-up because disease can recur decades after initial diagnosis and therapy. Considering the complexity of DTC management and the potential complications associated with therapy, it is essential that pediatric DTC be managed by physicians with expertise in this area.

Thyroid carcinoma in children and adolescents-systematic review of the literature

Thyroid cancer in children and adolescents is usually a major concern for physicians, patients, and parents. Controversies regarding the aggressiveness of the clinical presentation and the ideal therapeutic approach remain among the scientific community. The current recommendations and staging systems are based on data generated by studies in adults, and this might lead to overtreating in some cases as well as undertreating in others. Understanding the differences in the biology, clinical course, and outcomes in this population is crucial for therapeutic decisions. This paper evaluates the biology, clinical presentation, recurrences, and overall survival as well as the staging systems in children and adolescents with differentiated thyroid cancer.

Thyroid function and human reproductive health

Via its interaction in several pathways, normal thyroid function is important to maintain normal reproduction. In both genders, changes in SHBG and sex steroids are a consistent feature associated with hyper- and hypothyroidism and were already reported many years ago. Male reproduction is adversely affected by both thyrotoxicosis and hypothyroidism. Erectile abnormalities have been reported. Thyrotoxicosis induces abnormalities in sperm motility, whereas hypothyroidism is associated with abnormalities in sperm morphology; the latter normalize when euthyroidism is reached. In females, thyrotoxicosis and hypothyroidism can cause menstrual disturbances. Thyrotoxicosis is associated mainly with hypomenorrhea and polymenorrhea, whereas hypothyroidism is associated mainly with oligomenorrhea. Thyroid dysfunction has also been linked to reduced fertility. Controlled ovarian hyperstimulation leads to important increases in estradiol, which in turn may have an adverse effect on thyroid hormones and TSH. When autoimmune thyroid disease is present, the impact of controlled ovarian hyperstimulation may become more severe, depending on preexisting thyroid abnormalities. Autoimmune thyroid disease is present in 5-20% of unselected pregnant women. Isolated hypothyroxinemia has been described in approximately 2% of pregnancies, without serum TSH elevation and in the absence of thyroid autoantibodies. Overt hypothyroidism has been associated with increased rates of spontaneous abortion, premature delivery and/or low birth weight, fetal distress in labor, and perhaps gestation-induced hypertension and placental abruption. The links between such obstetrical complications and subclinical hypothyroidism are less evident. Thyrotoxicosis during pregnancy is due to Graves' disease and gestational transient thyrotoxicosis. All antithyroid drugs cross the placenta and may potentially affect fetal thyroid function.

Testicular steroidogenesis is not altered by 137 cesium Chernobyl fallout, following in utero or post-natal chronic exposure

The testis is especially sensitive to pollutants, including radionuclides. Following the Chernobyl nuclear power plant accident, several of these radionuclides were emitted and spread in the environment. Subsequently, children presented some disruptions of the endocrine system. To determine whether these disruptions were due to 137 cesium ((137)Cs) exposure, the effects of chronic contamination with low doses of (137)Cs in utero or from birth on testicular steroidogenesis in rats were studied. Contamination was continued for 9 months. No modification was observed in circulating level of hormones (17beta-estradiol, testosterone, follicle-stimulating hormone, luteinizing hormone) following in utero or post-natal contamination. Expression of several genes involved in testicular steroidogenesis was affected (cyp19a1, fxr, sf-1), without modification of protein expression or activity. Our results suggest that growing organisms may be affected at the molecular level by (137)Cs contamination at this post-accidental dose.

Assisted reproduction and fertility preservation techniques in cancer patients

PURPOSE OF REVIEW

This study aims to review the current state of different fertility preservation options in patients facing the risk of gonadal failure.

RECENT FINDINGS

Various malignant and nonmalignant diseases have been successfully treated with high-dose chemotherapy or radiotherapy. Even though many young patients receiving these treatments are at risk of developing reproductive failure, a number of fertility preservation options ranging from embryo cryopreservation to ovarian tissue cryopreservation are now available.

SUMMARY

Embryo cryopreservation is a well established technique to preserve fertility. The success rate with oocyte cryopreservation has been on the rise. Both oocyte and embryo freezing require ovarian stimulation and novel ovarian stimulation regimens utilizing aromatase inhibitors which have been developed for ovarian stimulation in women with estrogen sensitive cancer. Even though ovarian tissue cryopreservation is a novel technology, it is the only fertility preservation option for children and the only treatment strategy that can restore ovarian function. In-vitro maturation is a promising technology and can be applied in combination with ovarian tissue cryopreservation.

Radio-iodine therapy in differentiated thyroid cancer: indications and procedures

Post-surgical ablative iodine-131 therapy is recommended for all differentiated thyroid cancer primary tumors>1 cm in diameter. Regarding smaller primary tumors, 131I ablation may be helpful in special cases: tumor close to the thyroid capsule, previous percutaneous radiation to the neck, familial occurrence of thyroid cancer, tumor diameter 5-10 mm, and unfavorable histological variants. In this context, the patient's preferences for safety should be considered. In most centers, standard fixed activities of 1-3 GBq are used for 131I ablation. Preparation for the procedure with such activities requires a low-iodine diet for 2-3 weeks and stimulation of thyroid stimulating hormone (TSH) by withholding of thyroid hormone for 3 weeks following thyroidectomy or by use of recombinant human TSH. The advantages of recombinant TSH are avoidance of hypothyroid morbidity and consequently a better quality of life, as well as a lower radiation dose to extra-thyroidal compartments. To treat metastastic differentiated thyroid cancer, higher activities of radio-iodine (in the range 4-11 GBq) are necessary; if possible, individual dosimetry is recommended. The standard approach to preparation for 131I therapy in patients with metastases is endogenous hypothyroidism after thyroid hormone withdrawal.

Infertility and thyroid disorders

PURPOSE OF REVIEW

This review highlights the 'gap' in knowledge regarding the contribution of thyroid dysfunction in reproduction. Thyroid dysfunction, which is quite prevalent in the population affects many organs including the male and female gonads, interferes with human reproductive physiology, reduces the likelihood of pregnancy and adversely affects pregnancy outcome, thus becoming relevant in the algorithm of reproductive dysfunction.

RECENT FINDINGS

Although menstrual irregularities are common, ovulation and conception can still occur in hypothyroidism, where thyroxine treatment restores a normal menstrual pattern and reverses hormonal changes. Subclinical hypothyroidism may be associated with ovulatory dysfunction and adverse pregnancy outcome. Thyroid autoimmunity increases the miscarriage rate, and thyroxine treatment does not seem to protect. Menstrual disturbances, frequent in thyrotoxicosis are restored following treatment. In males, thyrotoxicosis has a significant but reversible effect on sperm motility. Although radioactive Iodine (I) in ablation doses may transiently affect the gonads, it does not decrease fertility or increase genetic malformation rate in the offspring.

SUMMARY

Awareness of the thyroid status in the infertile couple is crucial, because of its significant, frequent and often reversible or preventable effect on infertility. Many aspects of the role of thyroid disorders however in infertility need further research.