Reproductive outcomes and nononcologic complications after radioactive iodine ablation for well-differentiated thyroid cancer

Thyroid cancer

Thyroid cancer encountered during pregnancy requires a systematic approach balancing risks and benefits to both maternal and fetal health specific to this unique phase of life. Thyroid nodules are common and are predominantly evaluated to detect thyroid cancer. Clinical examination, serum thyroid stimulating hormone (TSH) measurement, ultrasonographic risk stratification, and fine needle aspiration biopsy when indicated are used to assess for malignancy. When thyroid cancer is diagnosed, further evaluation determines whether surgery during gestation is necessary or if delaying surgery until after delivery to minimize fetal and maternal risks is preferred. For patients who have undergone thyroidectomy for thyroid cancer, whether during pregnancy or before it, active management of levothyroxine therapy during pregnancy is recommended to ensure a sufficient thyroid hormone supply for both thyroid cancer treatment and optimal reproductive outcomes. This clinically oriented review summarizes key data, recommendations, and current trends regarding thyroid cancer care in pregnancy.

Radioactive Iodine Therapy in Differentiated Thyroid Cancer: Summary of the Korean Thyroid Association Guidelines 2024 from Nuclear Medicine Perspective, Part-II

Thyroid cancer, one of the most common endocrine tumors, generally has a favorable prognosis but remains a significant medical and societal concern due to its high incidence. Early diagnosis and treatment of differentiated thyroid cancer (DTC) significantly affect long-term outcomes, requiring the selection and application of appropriate initial treatments to improve prognosis and quality of life. Recent advances in technology and health information systems have enhanced our understanding of the molecular genetics of thyroid cancer, facilitating the identification of aggressive subgroups and enabling the accumulation of research on risk factors through big data. The Korean Thyroid Association (KTA) has revised the "KTA Guidelines on the Management of Differentiated Thyroid Cancers 2024" to incorporate these advances, which were developed by a multidisciplinary team and underwent extensive review and approval processes by various academic societies. This article summarizes the 2024 KTA guidelines for radioactive iodine (RAI) therapy in patients with DTC, written by the Nuclear Medicine members of the KTA Guideline Committee, and covers RAI therapy as initial management of DTC and RAI therapy in advanced thyroid cancer.

Pregnancy among thyroid cancer survivors: do thyroidectomy and radioactive iodine matter?

BACKGROUND

Thyroid cancer primarily affects young women and raises concerns about future fertility due to treatments of thyroidectomy and radioactive iodine (RAI) therapy. This study investigated the effects of these treatments on pregnancy probability in young female patients post-diagnosis.

METHODS

A nationwide, population-based study using data from Taiwan's National Health Insurance Research Database (2000-2017) examined pregnancy likelihood in women ≤45 years with thyroid cancer. The effects of thyroidectomy and RAI therapy on pregnancy were analyzed using logistic regression and Cox proportional-hazards models.

RESULTS

In a cohort of 10 937 patients with thyroid cancer, 7022 (64.2%) underwent total thyroidectomy, with 718 receiving RAI treatment. The type of thyroidectomy and RAI treatment, even at doses exceeding 120 millicuries, did not reduce the likelihood of pregnancy. Age was identified as the most critical factor influencing pregnancy; women aged >30 years had a significantly lower likelihood of becoming pregnant than younger women did. Other factors associated with a reduced likelihood of pregnancy included comorbidity with diabetes (HR = 0.65, P = .002) and higher socioeconomic status (HR = 0.69, P = .085).

CONCLUSIONS

Thyroidectomy and RAI therapy do not diminish pregnancy probability in young women with thyroid cancer. Age remains a crucial factor, with younger women more likely to conceive. These findings are critical for fertility counseling and treatment planning. Key message What is already known on this subjec?  Thyroid cancer primarily affects young women, and its standard treatments, including thyroidectomy and radioactive iodine (RAI) therapy, have raised concerns about their potential impact on fertility. Previous studies have shown that RAI treatment may temporarily affect ovarian function but typically does not have a significant long-term effect on fertility. What this study adds?  This nationwide population-based study found that neither total nor partial thyroidectomy, nor RAI treatment, adversely affects the likelihood of pregnancy in young women with thyroid cancer. Age was identified as the most significant factor influencing pregnancy, with younger women having a higher probability of becoming pregnant after treatment. How this study might affect research, practice, or policy?  Clinicians should recognize that age, rather than the type of thyroidectomy or RAI treatment, is the most critical factor influencing fertility in young women with thyroid cancer. This insight can guide personalized fertility counseling and treatment planning to optimize outcomes.

Exploring Serum Anti-thyroid Peroxidase Antibodies and High-Sensitivity C-reactive Protein as Inflammatory Markers in Subclinical Hypothyroidism: A Comprehensive Study

Background and aim Subclinical hypothyroidism (SCH) is a biochemical condition defined by elevated thyroid-stimulating hormone (TSH) levels with normal free thyroxine (FT4) levels, often occurring without overt clinical symptoms. Emerging evidence suggests a role for autoimmune and inflammatory processes, with anti-thyroid peroxidase antibodies (anti-TPO) and high-sensitivity C-reactive protein (hsCRP) as potential markers of thyroid autoimmunity and systemic inflammation. This study evaluates the significance of these markers in SCH to elucidate their association with disease progression and clinical symptoms. This study aims to assess the roles of anti-TPO and hsCRP as inflammatory markers in SCH and to examine their correlations with clinical symptoms, lipid profiles, and cardiovascular risk, to stratify patients based on their autoimmune and inflammatory profiles. Methodology A retrospective, cross-sectional study was conducted on 220 patients, including 170 diagnosed with SCH and 50 euthyroid controls. Patients were categorized into SCH with anti-TPO positivity (SCH+), SCH without anti-TPO positivity (SCH-), and euthyroid controls. Serum TSH, FT4, anti-TPO, and hsCRP levels were analyzed using chemiluminescent immunoassay (CLIA), enzyme-linked immunosorbent assay (ELISA), and turbidimetric immunoassay. Statistical analyses, including Kruskal-Wallis and correlation tests, evaluated associations between hsCRP, anti-TPO, and clinical parameters. Results SCH+ participants demonstrated significantly higher levels of TSH (7.6 ± 2.1 mIU/L), hsCRP (4.2 ± 1.6 mg/L), and anti-TPO antibodies (116.5 ± 34.8 IU/mL) compared to SCH- and controls (P < 0.001). hsCRP was elevated in 52.2% of SCH+ individuals, indicating a systemic inflammatory state, compared to 32.1% in SCH- and 16% in controls. Significant correlations were observed between hsCRP and TSH (r = 0.62, P < 0.001) and between hsCRP and anti-TPO (r = 0.58, P < 0.001) in SCH+ participants. SCH+ patients exhibited a higher prevalence of fatigue, cold intolerance, and lipid abnormalities, with total cholesterol and LDL levels markedly elevated compared to other groups. Conclusions Anti-TPO and hsCRP are valuable markers for identifying systemic inflammation and autoimmune activity in SCH, particularly in anti-TPO-positive individuals. Their integration into routine evaluation may help stratify SCH patients based on cardiovascular and metabolic risk, guiding early therapeutic interventions. Further, longitudinal studies are needed to explore their prognostic value and therapeutic implications.

Anti-Müllerian Hormone Can Help With Predicting Ovarian Failure for Premenopausal Women Who Have Undergone Ablative Radioiodine Treatment for Thyroid Cancer

Differentiated thyroid carcinoma is the most common endocrinological malignancy with an increasing incidence over the last 30 years, with women being more frequently affected. In indicated cases, total thyroidectomy followed by adjuvant radioiodine administration is performed, despite current trends towards less aggressive treatment. We would like to investigate the possible adverse effects of radioiodine (RAI) on ovarian function using a simple serum biomarker. Anti-Müllerian hormone (AMH) appears to be the best endocrine marker for assessing physiological age-related oocyte loss for healthy women. The aim of our ongoing prospective study is to determine serum AMH to estimate ovarian reserve for premenopausal women treated with RAI. Over the course of one year, 33 serum samples from women with thyroid cancer and 3 serum samples from healthy women were examined. AMH levels were compared before radioiodine treatment and at regular intervals after treatment. Mean of the AMH level was 5.4 ng/ml (n=33) prior to RAI. The average level of AMH decreased to 1.8 ng/ml in 4-6 months after treatment. In 22.2 % of patients AMH dropped to 0 ng/ml from a non-zero value. Thereafter, we observed an increase in AMH, the average value was 2.7 ng/ml in 8-12 months. We demonstrated a significant decrease in AMH shortly after radioiodine treatment and a subsequent trend of increase at one year after treatment. Consequently, predicting the adverse effects of radioiodine by assessing a serum biomarker could help to select an appropriate treatment strategy for young women planning pregnancy.

Thyroid cancer and pregnancy: a systematic ten-year-review

Background

Thyroid cancer is the second most common malignancy during pregnancy, especially the well-differentiated thyroid cancer (well-DTC). Therefore, complex medical and social dilemmas arise, dealing with which requires deep knowledge of the nature and characteristics of the disease and pregnancy as a whole. The purpose of this review is to present the diagnostic and therapeutic strategies of thyroid cancer during pregnancy and the postpartum period.

Methods

Extended review of the literature [2011-2023] was performed. Two hundred ninety-six articles were found, from which 225 were excluded due to irrelevant subjects. Seventy-one articles were assessed for eligibility, from which 33 articles were cohort studies and case reports and were included in the review.

Results

From the 33 included studies, 18 were retrospective cohort studies, 1 was cohort study, 2 were case control studies, 1 was meta-analysis and 11 were case reports. The primary endpoints of these studies refer to the progression and recurrence of DTC during pregnancy, the prevalence of thyroid cancer in pregnancy and the most appropriate time for surgical intervention.

Conclusions

The majority of the studies agree that well-differentiated tumors with mild clinical and imaging characteristics do not require immediate surgical treatment, but mere monitoring. Surgery can be delayed after childbirth. In contrast, tumors with aggressive behavior as well as non-differentiated ones, require immediate surgery because delay under these circumstances can dramatically reduce survival rates. Finally, a history of thyroid cancer does not seem to affect future deliveries, on condition that no residual disease exists at the onset of pregnancy.

Potential clinical application of anti-Müllerian hormone testing in radioiodine treatment of thyroid carcinoma

Differentiated thyroid cancer is the most common endocrinological malignancy. Radioiodine treatment has a clear benefit in locally aggressive and metastatic cancers. There are discussions about long-term and acute adverse events.Anti-Müllerian hormone is regarded as the best endocrine marker for evaluating the physiological loss of oocytes in healthy women with regard to age. The impact of radioiodine treatment on anti-Müllerian hormone levels has been more significantly reported in patients over 35 years of age. About reproductive dysfunction, calculations of individual absorbed doses of radioiodine in ovaries after thyroid cancer therapy have not been performed yet. The aim of our ongoing prospective study is to determine serum anti-Müllerian hormone to estimate ovarian reserve for premenopausal women treated with radioiodine and to compare anti-Müllerian hormone levels before and after radioiodine treatment. Predicting radioiodine side effects by evaluating a simple serum biomarker may help to select an appropriate treatment strategy for young women planning pregnancy, specifically in the assessment of ovarian reserve and premature ovarian failure with early onset of menopause.

[Female reproductive function after radioiodine therapy for differentiated thyroid carcinoma]

Differentiated thyroid carcinoma (DTC) is the most common endocrine cancer, accounting for 90-95% of thyroid malignancy and predominant in the female population of all age groups. Surgery is the standard primary treatment for patients with DTC, followed by radioactive iodine therapy (RAIT) when indicated. After the main treatment, patients receive thyroid hormone therapy in a variety of regimens, either as a replacement therapy or as a therapy intended to suppress secretion of thyroid-stimulating hormone (TSH).The impact of RAIT on the health of individuals with DTC has been studied for years. The accumulation of 131I in organs and tissues, as well as some organs' direct involvement in the metabolism of 131I-containing substances and its excretion, can lead to secondary complications. Reproductive health in the context of RAIT has also been a popular research topic because DTC is frequently found in young individuals.We may identify a direction for future study in this field and the requirement for adjustments in patient management thanks to the data summarized in this review on the effect of RAIT for DTC on female reproductive health.

Effect of women's fertility and sexual development on epigenetic clock: Mendelian randomization study

BACKGROUND AND OBJECTIVES

In observational studies, women's fertility and sexual development traits may have implications for DNA methylation patterns, and pregnancy-related risk factors can also affect maternal DNA methylation patterns. The aim of our study is to disentangle any potential causal associations between women's fertility and sexual development traits and epigenetic clocks, as well as to search for probable mediators by using the Mendelian randomization (MR) method.

METHODS

Instrumental variables for exposures, mediators, and outcomes were adopted from genome-wide association studies data of European ancestry individuals. The potential causal relationship between women's fertility and sexual development traits and four epigenetic clocks were evaluated by inverse variance weighted method and verified by other two methods. Furthermore, we employed multivariable MR (MVMR) adjusting for hypertension, hyperglycemia, BMI changes, and insomnia. Then, combining the MVMR results and previous research, we performed two-step MR to explore the mediating effects of BMI, AFS, and AFB. Multiple sensitivity analyses were further performed to verify the robustness of our findings.

RESULTS

Leveraging two-sample MR analysis, we observed statistically significant associations between earlier age at first birth (AFB) with a higher HannumAge, PhenoAge and GrimAge acceleration(β = - 0.429, 95% CI [- 0.781 to - 0.077], p = 0.017 for HannumAge; β = - 0.571, 95% CI [- 1.006 to - 0.136], p = 0.010 for PhenoAge, and β = - 1.136, 95% CI [- 1.508 to - 0.765], p = 2.03E-09 for GrimAge respectively) and age at first sexual intercourse (AFS) with a higher HannumAge and GrimAge acceleration(β = - 0.175, 95% CI [- 0.336 to - 0.014], p = 0.033 for HannumAge; β = - 0.210, 95% CI [- 0.350 to - 0.070], p = 0.003 for GrimAge, respectively). Further analyses indicated that BMI, AFB and AFS played mediator roles in the path from women's fertility and sexual development traits to epigenetic aging.

CONCLUSIONS

Our study suggested that AFS and AFB are associated with epigenetic aging. These findings may prove valuable in informing the development of prevention strategies and interventions targeted towards women's fertility and sexual development experiences and their relationship with epigenetic aging-related diseases.

Pregnancy outcomes and neonatal thyroid function in women with thyroid cancer: a retrospective study

BACKGROUND

Evidence regarding adverse pregnancy outcomes in patients with thyroid cancer has been conflicting, and the effect of thyroid dysfunction caused by thyroid hormone suppression therapy in terms of neonatal thyroid stimulating hormone (TSH) is unclear. This study aimed to investigate whether thyroid cancer was associated with adverse pregnancy outcomes and had an adverse effect on neonatal thyroid function.

METHODS

This was a retrospective study of 212 singleton pregnancies with thyroid cancer and 35,641 controls without thyroid cancer. Data on maternal pregnancy outcomes and neonatal outcomes were analyzed.

RESULTS

The median TSH level in the thyroid cancer group was significantly lower than that in the control group (0.87 µIU/mL vs. 1.17 µIU/mL; P < 0.001), while the FT4 level was higher than that in the control group (17.16 pmol/L vs. 16.33 pmol/L; P < 0.001). The percentage of thyroid peroxidase antibodies (TPOAb) positive in the thyroid cancer group was significantly higher than that in the control group (25.0% vs. 11.8%; P < 0.001). Pregnancies with thyroid cancer had a higher risk of late miscarriage (OR 7.166, 95% CI: 1.521, 33.775, P = 0.013), after adjusting maternal TPOAb positive, there was no statistical significance (OR 3.480, 95% CI: 0.423, 28.614, P = 0.246). Pregnancies with thyroid cancer had higher gestational weight gain (GWG) (14.0 kg vs. 13.0 kg, P < 0.001). Although there was no significant difference in the prevalence of gestational diabetes mellitus (GDM) (20.8% vs. 17.4%, P = 0.194), the oral glucose tolerance test (OGTT) showed that fasting plasma glucose and 2-hour value in the thyroid cancer group were higher than those in the control group (P = 0.020 and 0.004, respectively). There was no statistically significant difference in TSH between the thyroid cancer group and the control group, regardless of full-term newborns or preterm newborns.

CONCLUSIONS

Thyroid cancer might not have substantial adverse effects on pregnancy outcomes except for excessive GWG. No adverse effect on neonatal TSH was found, but the effect on long-term thyroid function and neuropsychological function in offspring need further study.

TRIAL REGISTRATION

Beijing Birth Cohort Study (ChiCTR220058395).

Infertility and Pregnancy Rates in Female Thyroid Cancer Survivors: A Retrospective Cohort Study Using Health Care Administrative Data from Israel

Background: Thyroid cancer (TC) is one of the most common carcinomas in young women. Concerns have been raised regarding the impact of the disease and its treatment on reproductive function. The aim of the study was to investigate the association of TC diagnosis and radioactive iodine (RAI) treatment on infertility and pregnancy rates in women. Methods: The comprehensive computerized database of a health management organization in Israel was screened for all female patients who were diagnosed with TC at age ≤40 years in 2000-2020. Rates of infertility (based on a documented diagnosis or purchase of fertility medications in the patient files) and pregnancy were compared with healthy age-matched controls. Results: The cohort included 1164 patients with TC (median age at diagnosis 31.6 years; interquartile range [IQR]: 26.7-35.4) and 5030 controls, followed for a median period of 10 years (IQR: 5.0-15.0). The infertility rate was higher in the TC group than in the control group (23.9% vs. 20.4%, p = 0.008). Still, the postdiagnosis/referent date pregnancy rates were comparable in the whole cohort (46.9/47.7%, p = 0.625) and across all age quartiles. The median time to the first pregnancy postdiagnosis/referent date was longer in TC patients than in controls (37 vs. 31 months, p < 0.001). Within the TC group, women who received repeated radioactive iodine treatment (n = 611, 52.5%) had comparable rates of infertility and pregnancy as those who did not. However, their time to the first postdiagnosis pregnancy was longer (median 45 vs. 29 months, p = 0.020). Conclusions: Our study provides reassuring evidence about the reproductive characteristics of women treated for TC. Pregnancy rates in TC survivors were comparable with controls. However, a higher infertility rate and a longer time to conceive were observed in the TC group compared with the control group. These findings were consistent in women who received single or repeated RAI treatments.

Association between thyroid cancer and cardiovascular disease: A meta-analysis

Objective

To determine the association between thyroid cancer and coronary artery disease, atrial fibrillation, cerebrovascular disease, and cardiovascular disease mortality.

Methods

The PubMed, Embase, and Cochrane Library databases were searched for eligible studies from inception to September 22, 2022. Keywords included "thyroid cancer", "atrial fibrillation", "coronary artery disease", "cerebrovascular disease", and "mortality". Primary outcomes included the incidence of coronary artery disease, cerebrovascular disease, atrial fibrillation, and cardiovascular disease mortality among patients with thyroid cancer. Secondary outcomes included cardiovascular disease events among those with thyroid cancer that received or did not receive radioactive iodine or lenvatinib. Estimates were pooled using fixed- and random-effects meta-analysis.

Results

A total of 771,220 patients who underwent thyroidectomy in 15 studies were included. Risk for cerebrovascular disease (risk ratio [RR] 1.15 [95% confidence interval (CI) 1.10-1.21]) and atrial fibrillation [RR 1.59 (95% CI: 1.45-1.73)] were significantly increased. Risk for coronary artery disease was significantly increased [RR 1.12 (95% CI: 1.08-1.17)] in the common effect model. Cardiovascular disease mortality associated with thyroid cancer was not significant [RR 0.93 (95% CI: 0.59-1.45)]. Radioactive iodine had a neutral effect on cardiovascular disease [RR 1.00 (95% CI: 0.87-1.16)], and there was no beneficial nor harmful effect among different RAI doses.

Conclusions

Thyroid cancer was significantly associated with a higher risk for cerebrovascular disease and atrial fibrillation; however, the hazard risk was not different between patients with and without radioactive iodine treatment. Thyroid cancer treatment should be individualized considering the potential harms and benefits to cardiovascular health.

Response to Surgery Assessments for Sparing Radioiodine Remnant Ablation in Intermediate-risk Papillary Thyroid Cancer

CONTEXT

Using response to surgery upon tailoring radioiodine (RAI) therapy for papillary thyroid cancer (PTC) is valued while lacking prospective validation.

OBJECTIVE

To spare RAI thyroid-remnant ablation among intermediate-risk PTCs by three-tiered assessments with response to surgery highlighted besides the risk of the recurrence stratification and TNM staging.

DESIGN, SETTING AND PARTICIPANTS

Patients with no evidence of disease (NED) identified as excellent response (ER) or indeterminate response (IDR) to surgery were spared from RAI thyroid-remnant ablation after informed consent and prospectively enrolled under active surveillance. Those involved in other trials or without sufficient follow-up data were excluded. Dynamic responses were followed and compared longitudinally.

MAIN OUTCOME MEASURES

NED presenting as durable ER or IDR for over 12 months.

RESULTS

Of the enrolled 215 patients, 47.4% (102/215) ER and 52.6% (113/215) IDR were identified upon RAI decision-making. After a median of 23.6 (IQR 13.8-31.6) months, the share of ER increased to 82.8%(178/215) and IDR decreased to 16.3% (35/215), with 85 patients shifting from IDR to ER over time, only 0.5% (1/215) structural and 0.5% (1/215) biochemical incomplete response observed. Successful remnant ablation was observed in 27.7%(26/94) of the patients completing two diagnostic whole-body scannings after a median interval of 13.0 months, indicating a theranostic effect. In the 173 patients followed for over 12 months, the NED rate didn't differ between ER and IDR subgroups (100% vs. 97.9%, P = 0.20).

CONCLUSIONS

Through the three-tiered assessments with response to surgery highlighted, postoperative ER and IDR spared from RAI remnant ablation may indicate similar favorable responses in intermediate-risk PTC patients during 23.6 months follow-up.

Risk of Adverse Pregnancy Outcomes in Young Women with Thyroid Cancer: A Systematic Review and Meta-Analysis

Simple Summary

This meta-analysis of 22 articles investigated whether thyroidectomy or radioactive iodine treatment (RAIT) in patients with differentiated thyroid cancer was associated with an increase in adverse pregnancy outcomes, such as miscarriage, preterm delivery, and congenital malformations. The results of this meta-analysis suggest that thyroid cancer treatment, including RAIT, is not associated with an increased risk of adverse pregnancy outcomes, including miscarriage, preterm labor, and congenital anomalies.

Abstract

This meta-analysis investigated whether thyroidectomy or radioactive iodine treatment (RAIT) in patients with differentiated thyroid cancer (DTC) was associated with an increase in adverse pregnancy outcomes, such as miscarriage, preterm delivery, and congenital malformations. A total of 22 articles (5 case-control and 17 case series studies) from 1262 studies identified through a literature search in the PubMed and EMBASE databases from inception up to 13 September 2021 were included. In patients with DTC who underwent thyroidectomy, the event rates for miscarriage, preterm labor, and congenital anomalies were 0.07 (95% confidence interval [CI], 0.05–0.11; 17 studies), 0.07 (95% CI, 0.05–0.09; 14 studies), and 0.03 (95% CI, 0.02–0.06; 17 studies), respectively. These results are similar to those previously reported in the general population. The risk of miscarriage or abortion was increased in patients with DTC when compared with controls without DTC (odds ratio [OR], 1.80; 95% CI, 1.28–2.53; I² = 33%; 3 studies), while the OR values for preterm labor and the presence of congenital anomalies were 1.22 (95% CI, 0.90–1.66; I² = 62%; five studies) and 0.73 (95% CI, 0.39–1.38; I² = 0%; two studies) respectively, which showed no statistical significance. A subgroup analysis of patients with DTC according to RAIT revealed that the risk of miscarriage, preterm labor, or congenital anomalies was not increased in the RAIT group when compared with patients without RAIT. The results of this meta-analysis suggest that thyroid cancer treatment, including RAIT, is not associated with an increased risk of adverse pregnancy outcomes, including miscarriage, preterm labor, and congenital anomalies.

Clinical course and outcome of differentiated thyroid cancer patients with pregnancy after diagnosis of distant metastasis

PURPOSE

There is no sufficient data about the clinical course and outcome in thyroid cancer patients who become pregnant after diagnosis of distant metastasis (DM). The current study was conducted to collect information regarding the clinical and reproductive characteristics, and outcomes in thyroid cancer patients who became pregnant after being diagnosed with DM.

METHODS

Records of 125 differentiated thyroid cancer (DTC) patients with age ≤45 years at DM diagnosis who had visited Ito Hospital from January 2005 to June 2021 were retrospectively reviewed. Among those 125 patients, 28 who became pregnant after DM diagnosis were classified as pregnancy group, and the remained 97 patients were classified as comparator group.

RESULTS

In pregnancy group, the median age at malignancy diagnosis, DM diagnosis, and first pregnancy after DM diagnosis was 25 years (range, 4-41 years), 27 years (range, 11-41 years), and 32 years (range, 25-45 years), respectively. Fifty-five pregnancies and 40 live births were reported. Other pregnancy outcomes were miscarriage (n = 14) and induced abortion (n = 1). The 10-year progression-free survival (PFS) rates of pregnant and comparator group were 92.1% and 74.4%, respectively (p = 0.018). The multivariate analysis showed that multiple ¹³¹I treatment was independent negative prognostic factor for PFS (p = 0.046).

CONCLUSIONS

DTC patients with age ≤45 years at DM diagnosis had good survival even though they became pregnant. Our results add to the information required for counseling thyroid cancer patients who have concerns about their fertility in the future.

Radioactive iodine and female fertility

Radioactive iodine (I131) is used after surgery in the treatment of Differentiated Thyroid Carcinoma (DTC). There is no solid evidence about the potential deleterious effect of I131 on women fertility. The objective of this study is to assess the impact that I131 may have on fertility in women. All women followed by DTC in our department have been analyzed and women younger than 45 years old at the time of diagnosis and initial treatment were included. There were 40 women exposed to I131 (study group) and 11 women who were only treated with thyroidectomy (control group). Of the women exposed to I131, 40% went through early menopause, while no cases were reported among their controls. Furthermore, 29.2% of women exposed to I131 had decreased Antimüllerian Hormone (AMH), compared to the only 11% of unexposed women (not significant). Regarding the fertility impairment "perceived" by patients, in the group of women exposed to iodine, 17.9% described being unable to complete their genesic desire whereas, none was registered in the control group. We conclude that radioactive iodine can affect a woman's fertility and shorten her reproductive life, so this is an aspect that should be taken into consideration.

Assessment of different markers of ovarian reserve in women with papillary thyroid cancer treated with radioactive iodine

Treatment with radioactive iodine (RAI) in women with differentiated thyroid cancer is associated with decreased serum concentrations of anti-Müllerian hormone (AMH); however, other markers have not been investigated. Therefore, this study aimed to evaluate the effect of RAI treatment on antral follicle count (AFC) and the serum concentration of inhibin B, follicle-stimulating hormone (FSH), and AMH in women with papillary thyroid cancer (PTC) treated with RAI. We examined 25 women at a median age of 33 years treated with a single dose of RAI. We divided the participants into women over (n = 11) and under 35 years of age (n = 14). Serum concentrations of inhibin B, FSH, AMH, and AFC were assessed at baseline and 1 year after RAI treatment. We found decreased AFC (P = 0.03), serum levels of AMH (P < 0.01), inhibin B (P = 0.03), but not FSH (P = 0.23), 1 year after RAI treatment in comparison to baseline in the whole group. When we compared serum levels of AMH in younger vs older women separately, we observed a significant reduction of this hormone's serum level after RAI treatment in both groups (P < 0.01; P = 0.04, respectively). We concluded that RAI treatment significantly impacts the functional ovarian reserve in premenopausal women with PTC.

Impact of thyroid cancer treatment on assisted reproductive technology outcomes in women with infertility

Purpose

We investigated the effect of different surgical procedures and radioactive iodine treatment (RAIT) on in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) outcomes and evaluated whether possible risk factors, including age, thyroid-stimulating hormone (TSH) levels, and thyroid antibody positivity, were associated with adverse IVF/ICSI outcomes.

Methods

This retrospective study included 76 women with infertility who had received thyroid cancer (TC) treatment among 137,698 infertile women who underwent IVF/ICSI cycles at the Peking University Third Hospital between 2010 and 2019. Clinical pregnancy and live birth rates were assessed.

Results

We found that the clinical pregnancy and live birth rates in women who underwent partial thyroidectomy were 7- and 6-fold higher, respectively, than those in women who underwent total thyroidectomy. We observed no significant differences in the clinical pregnancy and live birth rates between the RAIT and non-RAIT groups, even after adjusting for age, TSH levels, surgical treatment, and thyroid antibody positivity. Multivariate logistic regression analysis showed that age and TSH levels were not associated with decreased clinical pregnancy and live birth rates. Women with thyroid antibody positivity had significantly lower clinical pregnancy and live birth rates than women without thyroid antibody positivity.

Conclusion

Our study showed lower clinical pregnancy and live birth rates in women who underwent total thyroidectomy than in women who underwent partial thyroidectomy. Thyroid antibody positivity is an important risk factor for adverse IVF/ICSI outcomes in women who have received TC treatment.

The Effect of Radioactive Iodine Therapy on Ovarian Function and Fertility in Female Thyroid Cancer Patients: A Systematic Review and Meta-Analysis

Introduction: Thyroid cancer is one of the most common carcinomas diagnosed in adolescents and young adults, with a rapidly rising incidence for the past three decades. Surgery is the standard treatment for patients with differentiated thyroid carcinoma (DTC), and when indicated, followed by radioactive iodine (RAI) treatment. The aim of this study was to evaluate the possible effects of RAI therapy on ovarian function and fertility in women. Methods: The PubMed, Embase, and Web of Science databases were systematically searched up to January 2020. In addition, a meta-analyses were performed for anti-Mullerian hormone (AMH) levels after RAI, comparison of AMH levels prior and 1 year after RAI, and pregnancy rates in patient with thyroid cancer receiving RAI compared with patients with thyroid cancer who did not receive RAI. Results: A total of 36 studies were eligible for full-text screening and 22 studies were included. The majority of the studies had a retrospective design. Menstrual irregularities were present in the first year after RAI in 12% and up to 31% of the patients. Approximately 8-16% of the patients experienced amenorrhea in the first year after RAI. Women who received RAI treatment (median dose 3700 MBq [range 1110-40,700 MBq]); had menopause at a slightly younger age compared with women who did not receive RAI treatment, 49.5 and 51 years, respectively (p < 0.001). Pooled AMH of the seven studies reporting AMH concentrations after RAI was 1.79 ng/mL. Of these, four studies reported AMH concentrations prior and 1 year after RAI. The mean difference was 1.50 ng/mL, which was significant. Finally, meta-analysis showed that patients undergoing RAI were not at a decreased risk of becoming pregnant. Conclusions: Most of the studies indicate that RAI therapy for DTC is not associated with a long-term decrease in pregnancy rates although meta-analyses show a significant decrease in AMH levels after RAI therapy. Prospective studies are needed to confirm these results. We recommend counseling patients about the possible effects of ¹³¹I and incorporate today's knowledge in multidisciplinary counseling.

2021 European Thyroid Association Guideline on Thyroid Disorders prior to and during Assisted Reproduction

Severe thyroid dysfunction may lead to menstrual disorders and subfertility. Fertility problems may persist even after restoring normal thyroid function, and then an assisted reproductive technology (ART) may be a solution. Prior to an ART treatment, ovarian stimulation is performed, leading to high oestradiol levels, which may lead to hypothyroidism in women with thyroid autoimmunity (TAI), necessitating levothyroxine (LT4) supplements before pregnancy. Moreover, women with the polycystic ovarian syndrome and idiopathic subfertility have a higher prevalence of TAI. Women with hypothyroidism treated with LT4 prior to ART should have a serum TSH level <2.5 mIU/L. Subfertile women with hyperthyroidism planning an ART procedure should be informed of the increased risk of maternal and foetal complications, and euthyroidism should be restored and maintained for several months prior to an ART treatment. Fertilisation rates and embryo quality may be impaired in women with TSH >4.0 mIU/L and improved with LT4 therapy. In meta-analyses that mainly included women with TSH levels >4.0 mIU/L, LT4 treatment increased live birth rates, but that was not the case in 2 recent interventional studies in euthyroid women with TAI. The importance of the increased use of intracytoplasmic sperm injection as a type of ART on pregnancy outcomes in women with TAI deserves more investigation. For all of the above reasons, women of subfertile couples should be screened routinely for the presence of thyroid disorders.

Influence of Socioeconomic Status on Incident Medical Conditions in Two-Year Survivors of Adolescent or Young Adult Differentiated Thyroid Cancer

Purpose: We sought to enumerate secondary medical conditions from hospitalization records in adolescent and young adult (AYA) differentiated thyroid cancer (DTC) survivors and identify characteristics of patients with increased likelihood of subsequent medical diagnoses. Methods: Using data from the California Cancer Registry and statewide hospitalization data, we examined incident oncologic, endocrine, pulmonary, hematologic, and cardiovascular diagnoses in 12,312 AYA (aged 15-39) patients diagnosed with DTC in 1996-2012 and surviving >2 years after diagnosis with follow-up through 2014. We calculated the cumulative incidence of each condition accounting for the competing risk of death and used multivariable Cox proportional hazards regression to evaluate sociodemographic and clinical characteristics associated with each incident condition. Results: The 10-year cumulative incidences of multiple medical conditions were particularly high in blacks and Hispanics. Asian/Pacific Islander survivors were most likely to develop subsequent cancers. Men had higher rates of cardiovascular and diabetes diagnoses than women, but lower rates of asthma and cytopenias. Low socioeconomic status and/or public or no insurance were associated with a higher risk of several diagnoses. More extensive disease stage and thyroid surgery increased the risk of calcium and phosphorus metabolism disorders. Neck reoperation associated with the risk of cytopenias, as well as subsequent endocrine, cardiovascular, and respiratory diagnoses. Conclusions: The incidence of medical conditions after thyroid cancer diagnosis and treatment differ among racial/ethnic groups and sexes. Those residing in lower socioeconomic neighborhoods, those with public or no insurance, and those who require further neck surgery have substantially higher burdens of subsequent medical diagnoses.

Incidental detection, imaging modalities and temporal trends of differentiated thyroid cancer in Ontario: a population-based retrospective cohort study

BACKGROUND

Incidence rates of thyroid cancer in Ontario have increased more rapidly than those of any other cancer, whereas mortality rates have remained relatively stable. We evaluated the extent to which incidental detection of differentiated thyroid cancer during unrelated prediagnostic imaging procedures contributed to Ontario's incidence rates.

METHODS

We conducted a retrospective cohort study involving Ontarians who received a diagnosis of differentiated thyroid cancer from 1998 to 2017 using linked health care administrative databases. We classified cases as incidentally detected if a nonthyroid diagnostic imaging test (e.g., computed tomography [CT]) preceded an index event (e.g., prediagnostic fine-needle aspiration biopsy); all other cases were nonincidentally detected cases. We used Joinpoint and negative binomial regressions to characterize sex-specific rates of differentiated thyroid cancer by incidentally detected status and to quantify potential age, diagnosis period and birth cohort effects.

RESULTS

The study included 36 531 patients with differentiated thyroid cancer, of which 78.7% were female. Incidentally detected cases increased from 7.0% to 11.0% of female patients and from 13.5% to 18.2% of male patients over the study period. Age-standardized incidence rates increased more rapidly for incidentally detected cases (4.2-fold for female and 3.7-fold for male patients) than for nonincidentally detected cases (2.6-fold for female and 3.0-fold for male patients; p < 0.001). Diagnosis period was the primary factor associated with increased incidence rates of differentiated thyroid cancer, adjusting for other factors. Within each period, incidentally detected rates increased faster than nonincidentally detected rates, adjusting for age. Our results showed that CT was the most common imaging procedure preceding incidentally detected diagnoses.

INTERPRETATION

Incidentally detected cases represent a large and increasing component of the observed increases in differentiated thyroid cancer in Ontario over the past 20 years, and CT scans are primarily associated with these cases despite the modality having similar, increasing rates of use compared with magnetic resonance imaging (1993-2004). Recent increases in rates of differentiated thyroid cancer among males and incidentally detected cases among females in Ontario appear to be unrelated to birth cohort effects.

FIGO Stage IV and Age Over 55 Years as Prognostic Predicators in Patients With Metastatic Malignant Struma Ovarii

Introduction: Metastatic malignant struma ovarii (MSO) is an extremely rare disease that lacks treatment consensus and accurate prognosis. The objective of this study was to present the clinical, pathological, and treatment characteristics of metastatic MSO, while also investigate the overall survival (OS) rate and factors affecting prognosis in this population.

Materials and Methods: A total of 79 cases of metastatic MSO were reviewed, including four cases of metastatic MSO from our hospital and 75 cases selected from the literature. Logistic regression was used to identify potential factors affecting disease free survival (DFS). The Kaplan-Meier method and log-rank test were used to determine OS; further Cox regression was used to evaluate factors affecting OS.

Results: The mean age of all the patients at diagnosis was 43.8 years. The most common metastatic sites were peritoneum, bone, liver, omentum and lung in descending order. Only two patients (2.6%) coexisted with local primary thyroid cancer. Follicular carcinoma (41.8%) as the most prevalent subtype, followed by papillary carcinoma, follicular variant of papillary carcinoma, and mixed follicular-papillary carcinoma. 36.7% of the patients received conservative surgery, 43.0% of them underwent aggressive surgery, and 15.2% of them did not receive any surgery. 74.7% of patients who received adjuvant therapy underwent radioiodine therapy (RAI). Logistics regression revealed that FIGO stage IV was the only prognostic factor in predicting DFS (P = 0.002; Odds Ratio [OR] 5.333; 95% confidence interval [CI]: 1.839–15.471). Only seven deaths occurred. The OS rates at 5, 10, 15 years were 89.3, 82.4, 65.9%, respectively. Multivariate analysis showed age over 55 years (P = 0.006; OR 9.362; 95%CI: 1.895–46.246) was the only risk factor for OS.

Conclusion: Patients with metastatic MSO have an excellent disease-specific OS rate, FIGO stage IV and age over 55 years were two factors affecting disease prognosis. Conservative surgery with residual ablation by RAI after total thyroidectomy should be preferred since the benefits of aggressive surgery are uncertain.

Long-Term Effects of Radioiodine Treatment on Female Fertility in Survivors of Childhood Differentiated Thyroid Carcinoma

Background: Differentiated thyroid carcinoma (DTC) during childhood is a rare disease. Its excellent survival rate requires a focus on possible long-term adverse effects. This study aimed to evaluate fertility in female survivors of childhood DTC by assessing various reproductive characteristics combined with anti-Müllerian hormone (AMH) levels (a marker of ovarian reserve). Methods: Female survivors of childhood DTC, diagnosed at ≤18 years of age between 1970 and 2013, were included. Survivors were excluded when follow-up time was less than five years or if they developed other malignancies before or after diagnosis of DTC. Survivors filled out a questionnaire regarding reproductive characteristics (e.g., age at menarche and menopause, pregnancies, pregnancy outcomes, need for assisted reproductive therapy). Survivors aged <18 years during evaluation received an altered questionnaire without questions regarding pregnancy and pregnancy outcomes. These data were combined with information from medical records. AMH levels were measured in serum samples and were compared with AMH levels from 420 women not treated for cancer. Results: Fifty-six survivors with a median age of 31.0 (interquartile range, IQR, 25.1-39.6) years were evaluated after a median follow-up of 15.4 (IQR 8.3-24.7) years. The median cumulative dose of ¹³¹I administered was 7.4 (IQR 3.7-13.0) GBq/200.0 (IQR 100.0-350.0) mCi. Twenty-five of the 55 survivors aged 18 years or older during evaluation reported 64 pregnancies, 45 of which resulted in live birth. Of these 55, 10.9% visited a fertility clinic. None of the survivors reported premature menopause. Age at AMH evaluation did not differ between DTC survivors and the comparison group (p = 0.268). Median AMH levels did not differ between DTC survivors and the comparison group [2.0 (IQR 1.0-3.7) μg/L vs. 1.6 (IQR 0.6-3.1) μg/L, respectively, p = 0.244]. The cumulative dose of ¹³¹I was not associated with AMH levels in DTC survivors (r_s = 0.210, p = 0.130). Conclusions: Female survivors of DTC who received ¹³¹I treatment during childhood do not appear to have major abnormalities in reproductive characteristics nor in predictors of ovarian failure.

Thyroid nodules and cancer during pregnancy, post-partum and preconception planning: Addressing the uncertainties and challenges

Thyroid nodules and thyroid cancer have become increasingly common worldwide. When discovered during pregnancy, they pose unique diagnostic and therapeutic challenges for both the treating physician and the patient. The benefits of treatment should be carefully weighed against risks that may adversely impact maternal and fetal health. In this review, we present current knowledge and controversies surrounding the management of thyroid nodules and thyroid cancer in pregnancy, in the post-partum period and during preconception planning.

Thyroid and Fertility: Recent Advances

Background: Thyroid disease is prevalent in women of reproductive age, while infertility is common in women with thyroid dysfunction. In this study, we review the recent advances in the field of thyroid and fertility since the publication of the 2017 American Thyroid Association pregnancy guidelines. Summary: Recent studies have confirmed associations of thyrotropin (TSH) elevation and/or thyroid autoimmunity with infertility and low ovarian reserve in subsets of women, and have led to a better understanding of the pathogenesis linking thyroid autoimmunity with infertility. Even though the benefit of treating patients with TSH >4 mIU/L has been confirmed in a large retrospective cohort study, two large randomized controlled trials have failed to show benefit of thyroid hormone on obstetrical outcomes in euthyroid women with thyroid autoimmunity. New data have emerged regarding the potential gonadal toxicity of radioactive iodine (RAI), based on its impact on ovarian reserve and sperm chromosomal abnormalities. Conclusions: There is continued evidence supporting an important role of thyroid hormone in regulation of reproductive tissues at many levels. Recent randomized trials have failed to identify a benefit of thyroid hormone in euthyroid women with thyroid autoimmunity. Further research in the field is needed to more completely delineate the relevant pathways and identify women who may benefit from levothyroxine treatment. The impact of RAI on fertility also merits further investigation.

Fertility in female cancer survivors: a systematic review and meta-analysis

Data on the effects of cancer treatments on fertility are conflicting. The aim of the present systematic review and meta-analysis was to determine the chances of childbirth in women survivors of different types of cancer. PubMed, MEDLINE, Embase and Scopus were searched from database inception to 17 July 2019 for published cohort, case-control and cross-sectional studies that investigated the reproductive chances in women survivors of different cancer types. Random-effects models were used to pool childbirth hazard ratios, relative risks, rate ratios and odds ratios, and 95% confidence intervals were estimated; 18 eligible studies were identified. Childbirth chances were significantly reduced in women with a history of bone cancer (HR 0.86, 95% CI 0.77 to 0.97; I² = 0%; P = 0.02 (two studies); RaR 0.76, 95% CI 0.61 to 0.95; I² = 69%; P = 0.01 (two studies); breast cancer (HR 0.74, 95% CI 0.61 to 0.90 (one study); RaR 0.51, 95% CI 0.47 to 0.57; I² = 0%; P < 0.00001 (two studies); brain cancer (HR 0.61, 95% CI 0.51 to 0.72; I² = 14%; P < 0.00001 (three studies); RR 0.62, 95% CI 0.42 to 0.91 (one study); RaR 0.44, 95% CI 0.33 to 0.60; I² = 95%; P < 0.00001 (four studies); OR 0.49, 95% CI 0.40 to 0.60 (one study); and kidney cancer (RR 0.66, 95% CI 0.43 to 0.98 (one study); RaR 0.69, 95% CI 0.61 to 0.78 (one study). Reproductive chances in women survivors of non-Hodgkin's lymphoma, melanoma and thyroid cancer were unaffected. Women with a history of bone, breast, brain or kidney cancer have reduced chances of childbirth. Thyroid cancer, melanoma and non-Hodgkin's lymphoma survivors can be reassured.

Association Between Pregnancy Outcomes and Radioactive Iodine Treatment After Thyroidectomy Among Women With Thyroid Cancer

IMPORTANCE

Current guidelines recommend that women delay pregnancy for 6 to 12 months after the receipt of radioactive iodine treatment (RAIT) following thyroidectomy for differentiated thyroid carcinoma. Although concerns exist regarding the risks associated with pregnancy after RAIT, no large-scale study, to date, has investigated the association between RAIT and pregnancy outcomes.

OBJECTIVE

To investigate whether RAIT was associated with increases in adverse pregnancy outcomes among South Korean women who received RAIT after thyroidectomy for thyroid cancer and to evaluate the appropriate interval between RAIT and conception.

DESIGN, SETTING, AND PARTICIPANTS

This population-based cohort study used the Health Insurance Review and Assessment database of South Korea to identify a total of 111 459 women of childbearing age (20-49 years) who underwent thyroidectomy for the treatment of differentiated thyroid carcinoma between January 1, 2008, and December 31, 2015. Participants were allocated to 2 cohorts: those who underwent surgery alone (n = 59 483 [53.4%]) and those who underwent surgery followed by RAIT (n = 51 976 [46.6%]). The pregnancy outcomes data were collected from January 1, 2008, to December 31, 2017.

MAIN OUTCOMES AND MEASURES

The rates of abortion (both spontaneous and induced), preterm delivery, and congenital malformation were assessed. Multivariate logistic regression models were used to control for confounding variables.

RESULTS

Among the 111 459 women of childbearing age who underwent thyroidectomy with or without RAIT for the treatment of thyroid cancer, the mean (SD) age at surgery or RAIT was 39.8 (6.7) years. Of those, 10 842 women (9.7%) became pregnant, and the mean (SD) age at conception was 33.3 (4.4) years. The rates of abortion, preterm delivery, and congenital malformation among patients who underwent surgery alone compared with patients who underwent surgery followed by RAIT were 30.7% vs 32.1% for abortion, 12.8% vs 12.9% for preterm delivery, and 8.9% vs 9.0% for congenital malformation, respectively (P > .05). A subgroup analysis based on the interval between RAIT and conception indicated congenital malformation rates of 13.3% for the interval of 0 to 5 months, 7.9% for 6 to 11 months, 8.3% for 12 to 23 months, and 9.6% for 24 months or more. The adjusted odds ratio of congenital malformation was 1.74 (95% CI, 1.01-2.97; P = .04) in conceptions that occurred 0 to 5 months after RAIT compared with conceptions that occurred 12 to 23 months after RAIT. The abortion rates based on the interval between RAIT and conception were 60.6% for the interval of 0 to 5 months, 30.1% for 6 to 11 months, 27.4% for 12 to 23 months, and 31.9% for 24 months or more.

CONCLUSIONS AND RELEVANCE

These large-scale real-world data indicate that receipt of RAIT before pregnancy does not appear to be associated with increases in adverse pregnancy outcomes when conception occurs 6 months or more after treatment.

Dual inhibition of BRAF and MEK increases expression of sodium iodide symporter in patient-derived papillary thyroid cancer cells in vitro

BACKGROUND

The majority of papillary thyroid cancers are driven by acquired mutations typically in the BRAF or RAS genes that aberrantly activate the mitogen-activated protein kinase pathway. This process leads to malignant transformation, dedifferentiation, and a decrease in the expression of the sodium-iodide symporter (NIS; SLC5A5), which results in resistance to radioactive iodine therapy. We sought to determine whether inhibition of aberrant mitogen-activated protein kinase-signaling can restore NIS expression.

METHODS

We prospectively developed cultures of papillary thyroid cancers derived from operative specimens and applied drug treatments for 24 hours. Samples were genotyped to identify BRAF and RAS mutations. We performed quantitative PCR to measure NIS expression after treatment.

RESULTS

We evaluated 24 patient papillary thyroid cancer specimens; BRAF^V600E mutations were identified in 18 out of 24 (75.0%); 1 patient tumor had an HRAS mutation, and the remaining 5 were BRAF and RAS wildtype. Dual treatment with dabrafenib and trametinib increased NIS expression (mean fold change 4.01 ± 2.04, P < .001), and single treatment with dabrafenib had no effect (mean fold change 0.98 ± 0.42, P = .84). Tumor samples that had above-median NIS expression increases came from younger patients (39 vs 63 years, P < .05).

CONCLUSION

Dual treatment with BRAF and MEK inhibitors upregulated NIS expression, suggesting that this treatment regimen may increase tumor iodine uptake. The effect was greatest in tumor cells from younger patients.

Effects of Radioactive Iodine Therapy on Ovarian Reserve: A Prospective Pilot Study

Background: Thyroid carcinoma is the most common endocrine malignancy. Surgery is the standard therapeutic approach for patients with differentiated thyroid carcinoma (DTC), followed by radioiodine (RAI) therapy if indicated. For women with DTC, the effects of RAI therapy on gonadal and reproductive function are an important consideration. This study aimed to evaluate the effects of RAI therapy on ovarian function. Methods: A total of 33 premenopausal women were enrolled in this study. Serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol, and anti-Müllerian hormone (AMH) levels during the early follicular phase were measured before and 3, 6, and 12 months after RAI therapy. The Friedman and Wilcoxon tests were used to detect changes in FSH, AMH, LH, and estradiol levels induced by RAI therapy over time. Results: The patients' ages ranged from 21 to 38 years, with a mean age of 31.15 ± 4.83 years. The median follow-up was 19 months (range 4-26 months). The median AMH levels were 3.25 ng/mL (range 0.32-17.42 ng/mL), 1 ng/mL (range 0.01-3.93 ng/mL), 1.13 ng/mL (range 0.08-6.12 ng/mL), and 1.37 ng/mL (range 0.09-6.1 ng/mL) before and at 3, 6, and 12 months after RAI therapy, respectively. The median FSH levels were 6.6 mIU/mL (range 3.78-15.5 mIU/mL), 5.83 mIU/mL (range 4.19-35.36 mIU/mL), 7.71 mIU/mL (range 4.24-16.25 mIU/mL), and 7.04 mIU/mL (range 4.93-19.96 mIU/mL) before and at 3, 6, and 12 months after RAI therapy, respectively. The AMH levels were higher before than after RAI therapy (p = 0.001). The AMH levels did not differ significantly between the three time points (p > 0.05). The FSH, LH, and estradiol levels were similar before and after RAI therapy (p > 0.05). Conclusion: AMH is considered an important marker of ovarian reserve. Ovarian reserve decreased after RAI therapy. More attention may be needed when considering RAI therapy for patients with reduced ovarian reserve.

Reproductive and gynecological complication risks among thyroid cancer survivors

PURPOSE

Thyroid cancer is the most rapidly increasing cancer in the USA, affects a young, mostly female population, and has high survival. The aim of this study was to determine if there is an increased risk of reproductive system adverse events or pregnancy complications among women diagnosed with thyroid cancer under the age of 50.

METHODS

Up to five female cancer-free individuals were matched to each female thyroid cancer survivor diagnosed before the age of 50 based on birth year, birth state, and follow-up time, within the Utah Population Database. Medical records were used to identify disease diagnoses stratified over three time periods: 0-1, > 1-5, and > 5-10 years after cancer diagnosis. Cox proportional hazards models were used to estimate hazard ratios (HR) with adjustment on matching factors, race, BMI, and Charlson Comorbidity Index.

RESULTS

There were 1832 thyroid cancer survivors and 7921 matched individuals. Thyroid cancer survivors had higher rates of having multiple health conditions associated with the gynecological system (15.4% vs. 9.4%) and pregnancy (14.3% vs 9.5%) > 1-5 years after cancer diagnosis. Increased risks persisted > 5-10 years after cancer diagnosis for menopausal disorders (HR = 1.78, 99% CI = 1.37, 2.33) and complications related to pregnancy (HR = 2.13, 99% CI = 1.14, 3.98). Stratified analyses showed these risks remained increased across different treatment types.

CONCLUSIONS

There were significant risk increases in reproductive system and pregnancy complications among female thyroid cancer survivors within this study.

IMPLICATIONS FOR CANCER SURVIVORS

Although radiation has been linked to reproductive risks in previous studies, we found risks were increased in patients regardless of treatment.

Factors Associated with Dose Determination of Radioactive Iodine Therapy for Differentiated Thyroid Cancer

Radioactive iodine (RAI) therapy for differentiated thyroid cancer has been successfully used for more than 70 years. However, there is still plenty of controversy surrounding the use and doses of radioiodine. There is insufficient evidence to answer the questions. Recent American Thyroid Association (ATA) guidelines seem to favor low-dose RAI, based on recent clinical trials and meta-analyses. However, long-term follow-up data remains limited, and there are additional factors we should consider that might affect the efficacy of RAI therapy. Therefore, until sufficient data are available, it is necessary to remain cautious about determining RAI doses by considering multiple patient-specific variables.

Italian consensus on diagnosis and treatment of differentiated thyroid cancer: joint statements of six Italian societies

BACKGROUND

Thyroid nodules are a common clinical problem, and differentiated thyroid cancer is becoming increasingly prevalent.

METHODS

Six scientific Italian societies entitled to cure thyroid cancer patients (the Italian Thyroid Association, the Medical Endocrinology Association, the Italian Society of Endocrinology, the Italian Association of Nuclear Medicine and Molecular Imaging, the Italian Society of Unified Endocrine Surgery and the Italian Society of Anatomic Pathology and Diagnostic Cytology) felt the need to develop a consensus report based on significant scientific advances occurred in the field.

OBJECTIVE

The document includes recommendations regarding initial evaluation of thyroid nodules, clinical and ultrasound criteria for fine-needle aspiration biopsy, initial management of thyroid cancer including staging and risk assessment, surgical management, radioiodine remnant ablation, and levothyroxine therapy, short-term and long-term follow-up strategies, and management of recurrent and metastatic disease. The objective of this consensus is to inform clinicians, patients, researchers, and health policy makers about the best strategies (and their limitations) relating to the diagnosis and treatment of differentiated thyroid cancer.

A Single Radioactive Iodine Treatment Has a Deleterious Effect on Ovarian Reserve in Women with Thyroid Cancer: Results of a Prospective Pilot Study

BACKGROUND

Women of reproductive age with differentiated thyroid cancer (DTC) often need radioactive iodine (RAI) treatment after surgery. In contrast to the well-documented effect of RAI on testicular function, the potential negative effects of this treatment on ovarian reserve have been largely dismissed. The objective of this pilot study was to examine the possibility that RAI treatment is deleterious to the ovarian reserve by prospectively measuring the concentration of anti-Müllerian hormone (AMH) after RAI treatment.

METHODS

Thirty premenopausal women (M_age = 34 years; range 20-45 years) with a new diagnosis of DTC scheduled to undergo RAI ablation were recruited for this study. All of them had TNM stage 1 disease (T1-3, N0, or N1, M0), and were scheduled to receive RAI activities ranging from 30 to 150 mCi. AMH was measured at baseline and at 3, 6, 9, and 12 months after the administration of RAI.

RESULTS

Of the 30 women, only 24 returned after the baseline assessment. RAI treatment resulted in a significant decrease in AMH concentrations at three months, from 3.25 ± 2.75 to 1.9 ± 1.74 ng/mL (p < 0.0001). Only partial recovery was subsequently documented. Eighty-two percent of subjects had final values below baseline levels, such that at one year, serum AMH was still 32% lower than prior to treatment (2.36 ± 1.88 ng/mL; p < 0.005). The only two continuous variables that correlated with the extent of AMH reduction at three months were the woman's age (r = 0.51; p = 0.02) and the age at menarche (r = 0.48; p = 0.03). Importantly, the RAI dose was not associated with the extent of AMH reduction and neither were smoking or the use of birth control pills. Older subjects (≥35 years) were significantly more likely to experience a marked AMH reduction at three months (63.7 ± 18.5% vs. 33.1 ± 29.2%; p = 0.01). The only predictor of recovery after one year was the extent of AMH decrease at three months: the lower the decline, the higher the chances for recovery.

CONCLUSIONS

RAI in DTC has a rapid and profound effect on ovarian reserve, with only a partial recovery potential. In an era of declining human fertility, it is of relevance to recognize the potentially adverse effect of RAI in women of reproductive age. AMH measurement may be useful as a tool in this decision-making process.

Optimization of the risk-benefit ratio of differentiated thyroid cancer treatment

The vast majority of differentiated thyroid cancers (DTC) are characterized by an innocuous nature, excellent patient survival, and limited treatment requirement. However, a significant proportion of affected patients is prone to receiving overtreatment, due to undertreatment concerns associated with the difficulty to differentiate them from a small minority affected by aggressive DTC. Identification of prognostic factors and development of staging systems has helped to reduce the proportion of overtreatment in DTC. However, the absolute number of overtreated patients continues to increase, as a result of an on-going incidence surge in early DTC associated with the increased application and sensitivity of modern diagnostic tools. In the present paper, we describe how DTC treatment can be optimized by thoughtful evidence-based balancing of oncologic safety against treatment associated morbidity.

Aging-Related Disease Risks among Young Thyroid Cancer Survivors

Background: Thyroid cancer is the most rapidly increasing cancer in the United States, affects a young population, has high survival, and is one of the most common cancers in people under age 40. The aim of this study was to examine the risks of aging-related diseases in a statewide sample of thyroid cancer survivors who were diagnosed <40 years compared with those diagnosed ≥40 and a cancer-free sample.Methods: Thyroid cancer survivors diagnosed 1997 to 2012 were matched to up to 5 cancer-free individuals on birth year, sex, birth state, using the statewide Utah Population Database. Medical records were used to identify disease diagnoses stratified over three time periods: 1 to 5, >5 to 10, and 10+ years after cancer diagnosis. Cox proportional hazards models were used to estimate hazard ratios with adjustment on matching factors, race, body mass index, and Charlson Comorbidity Index.Results: There were 3,706 thyroid cancer survivors and 15,587 matched cancer-free individuals (1,365 cases diagnosed <40 years old). Both age groups had increased risks for multiple circulatory health conditions 1 to 5 years after cancer diagnosis compared with cancer-free individuals. Survivors <40 had a higher risk of hypertension, cardiomyopathy, and nutritional deficiencies.Conclusions: Increased risks for diseases associated with aging were observed for both age groups, with younger thyroid cancer survivors having higher risks for select diseases.Impact: As thyroid cancer survivors in this study were found to have increased risks for aging-related diseases, future studies are needed to assess what can be done to reduce the increased risks of these long-term health effects. Cancer Epidemiol Biomarkers Prev; 26(12); 1695-704. ©2017 AACR.

Birth rates after radioactive iodine treatment for differentiated thyroid cancer

Treatment with radioactive iodine (RAI) for differentiated thyroid cancer has been associated with alterations in gonadal function in women, including changes in menstrual function and an earlier age at menopause. Our objective was to evaluate associations between RAI and postdiagnosis live birth rates among thyroid cancer survivors diagnosed at ages 15-39 years. We identified women diagnosed with differentiated thyroid cancer between January 2000 and December 2013 in the North Carolina Central Cancer Registry (CCR). CCR records were linked to state birth certificate files to identify livebirths to thyroid cancer survivors through December 2014. Person-years of follow-up were accrued from 6 months after diagnosis to first birth, 46th birthday, death, or December 31, 2014, whichever came first. Cox proportional hazards regression was used to estimate hazards ratios (HR) and 95% confidence intervals (CI) for first livebirth. Among 2,360 women with a differentiated thyroid cancer diagnosis, 53% received RAI. The cumulative incidence of birth at the end of follow-up (maximum 14.5 years) was 30.0 and 29.3% among those who were and were not treated with RAI, respectively. Overall, first birth rates did not significantly differ between groups (HR = 1.00; 95% CI: 0.82, 1.23). In our observational cohort, treatment with RAI was not associated with a reduced birth rate. Our findings add to the evidence available for counseling thyroid cancer patients with concerns about future fertility.

Radioiodine Ablation following Thyroidectomy for Differentiated Thyroid Cancer: Literature Review of Utility, Dose, and Toxicity

Management recommendations for differentiated thyroid cancer are evolving. Total thyroidectomy is the backbone of curative-intent therapy, with radioiodine ablation (RAI) of the thyroid remnant routinely performed, in order to facilitate serologic surveillance and reduce recurrence risk. Several single-institution series have identified patient subsets for whom recurrence risk is sufficiently low that RAI may not be indicated. Further, the appropriate dose of RAI specific to variable clinicopathologic presentations remains poorly defined. While recent randomized trials demonstrated equivalent thyroid remnant ablation rates between low- and high-dose RAI, long-term oncologic endpoints remain unreported. While RAI may be employed to facilitate surveillance following total thyroidectomy, cancer recurrence risk reduction is not demonstrated in favorable-risk patients with tumor size ≤1 cm without high-risk pathologic features. When RAI is indicated, in patients without macroscopic residual disease or metastasis, the evidence suggests that the rate of successful remnant ablation following total thyroidectomy is equivalent between doses of 30-50 mCi and doses ≥100 mCi, with fewer acute side effects; however, in the setting of subtotal thyroidectomy or when preablation diagnostic scan uptake is >2%, higher doses are associated with improved ablation rates. Historical series demonstrate conflicting findings of long-term cancer control rates between dose levels; long-term results from modern series have yet to be reported. For high-risk patients, including those with positive surgical margins, gross extrathyroidal extension, lymph node involvement, subtotal thyroidectomy, or >5% uptake, higher-dose RAI therapy appears to provide superior rates of ablation and cancer control.

Pregnancy Outcome After I-131 Therapy for Patients With Thyroid Cancer: A Nationwide Population-Based Cohort Study

The aim of this study was to evaluate the influence of I-131 therapy on pregnancy outcome in patients that received therapeutic I-131 doses for thyroid cancer in Taiwan.This nationwide population-based cohort study was based on data from 1998 to 2010 obtained from the Taiwanese National Health Insurance Research Database. We identified 11,708 women with thyroid cancer (≥ 15 and ≤ 50 years of age) by International Classification of Diseases, Ninth Revision, Clinical Modification codes. Patients were divided into 2 cohorts: I-131 therapy cohort and non-I-131 therapy cohort. The mean follow-up period was 6.08 years for the I-131 cohort and 6.87 years for the non-I-131 cohort. The case cohort and the control cohort comprised 775 and 716 pregnant patients, respectively.The overall incidence of pregnancy was significantly lower in the I-131 cohort (adjusted HR = 0.77, 95% CI = 0.70-0.86) and it was also observed when the patients were stratified according to age (HR = 0.73, 95% CI = 0.64-0.83 in 25-34 years; HR = 0.63, 95% CI = 0.49-0.82 in 35-44 years). Patients in the I-131 cohort had a lower successful delivery rate, particularly among patients in 25 to 34 years (OR = 0.60, 95% CI = 0.45-0.80). No significant difference was observed for adverse pregnancy conditions between 2 cohorts.I-131 therapy is associated with decreased pregnancy and successful delivery rates. The underlying mechanism likely involves physician recommendation, patient's psychological issue, and potential impact of I-131 treatment on reproductive health. Further investigation is needed.

2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer: The American Thyroid Association Guidelines Task Force on Thyroid Nodules and Differentiated Thyroid Cancer

BACKGROUND

Thyroid nodules are a common clinical problem, and differentiated thyroid cancer is becoming increasingly prevalent. Since the American Thyroid Association's (ATA's) guidelines for the management of these disorders were revised in 2009, significant scientific advances have occurred in the field. The aim of these guidelines is to inform clinicians, patients, researchers, and health policy makers on published evidence relating to the diagnosis and management of thyroid nodules and differentiated thyroid cancer.

METHODS

The specific clinical questions addressed in these guidelines were based on prior versions of the guidelines, stakeholder input, and input of task force members. Task force panel members were educated on knowledge synthesis methods, including electronic database searching, review and selection of relevant citations, and critical appraisal of selected studies. Published English language articles on adults were eligible for inclusion. The American College of Physicians Guideline Grading System was used for critical appraisal of evidence and grading strength of recommendations for therapeutic interventions. We developed a similarly formatted system to appraise the quality of such studies and resultant recommendations. The guideline panel had complete editorial independence from the ATA. Competing interests of guideline task force members were regularly updated, managed, and communicated to the ATA and task force members.

RESULTS

The revised guidelines for the management of thyroid nodules include recommendations regarding initial evaluation, clinical and ultrasound criteria for fine-needle aspiration biopsy, interpretation of fine-needle aspiration biopsy results, use of molecular markers, and management of benign thyroid nodules. Recommendations regarding the initial management of thyroid cancer include those relating to screening for thyroid cancer, staging and risk assessment, surgical management, radioiodine remnant ablation and therapy, and thyrotropin suppression therapy using levothyroxine. Recommendations related to long-term management of differentiated thyroid cancer include those related to surveillance for recurrent disease using imaging and serum thyroglobulin, thyroid hormone therapy, management of recurrent and metastatic disease, consideration for clinical trials and targeted therapy, as well as directions for future research.

CONCLUSIONS

We have developed evidence-based recommendations to inform clinical decision-making in the management of thyroid nodules and differentiated thyroid cancer. They represent, in our opinion, contemporary optimal care for patients with these disorders.