Serial Neck Ultrasonographic Evaluation of Changes in Papillary Thyroid Carcinoma During Pregnancy

Pregnancy and Progression of Differentiated Thyroid Cancer: A Propensity Score-Matched Retrospective Cohort Study

CONTEXT AND OBJECTIVE

Differentiated thyroid cancer (DTC) is very common in women of reproductive age. However, it remains unclear whether pregnancy is associated with DTC progression before surgical treatment.

METHODS

This retrospective cohort study, conducted at the Peking University Third Hospital in Beijing, China between January 2012 and December 2022, included 311 eligible women aged 20 to 45 years. To control for potential confounders, we first used propensity score matching (PSM) to match the pregnant group (n = 48) with the nonpregnant group (n = 154) on age, tumor size, tumor type, and Hashimoto's thyroiditis status at baseline, and then used Cox proportional risk models stratified by the matched pairs to estimate the association of pregnancy with DTC progression.

RESULTS

After PSM, the pregnant and nonpregnant groups were well comparable at baseline (standardized difference < 10% and P > .05). Over an average observation period of 2.5 years, we observed no difference between the pregnant group and the matched nonpregnant group in DTC progression-free survival (hazard ratio [HR] = 0.96; 95% CI, 0.56 to 1.65; P = .895), tumor enlargement-free survival (HR = 0.99; 95% CI, 0.56 to 1.76; P = .969) or lymph node metastasis-free survival (LNM) (HR = 0.67; 95% CI, 0.21 to 2.13; P = .498). The postoperative pathological characteristics also showed no significant difference between the pregnant and nonpregnant groups (P > .05).

CONCLUSION

Pregnancy seemed to be irrelevant to DTC progression-free survival before surgical treatment. Further prospective cohort studies are needed to translate this finding into clinical practice.

A Narrative Review of the 2023 Korean Thyroid Association Management Guideline for Patients with Thyroid Nodules

The 2023 Korean Thyroid Association (KTA) Management Guideline for Patients with Thyroid Nodules constitute an update of the 2016 KTA guideline for thyroid nodules and cancers that focuses specifically on nodules. The 2023 guideline aim to offer updated guidance based on new evidence that reflects the changes in clinical practice since the 2016 KTA guideline. To update the 2023 guideline, a comprehensive literature search was conducted from January 2022 to May 2022. The literature search included studies, reviews, and other evidence involving human subjects that were published in English in MEDLINE (PubMed), Embase, and other relevant databases. Additional significant clinical trials and research studies published up to April 2023 were also reviewed. The limitations of the current evidence are discussed, and suggestions for areas in need of further research are identified. The purpose of this review is to provide a summary of the 2023 KTA guideline for the management of thyroid nodules released in May 2023 and to give a balanced insight with comparison of recent guidelines from other societies.

Thirty years of active surveillance for low-risk thyroid cancer, lessons learned and future directions

Active Surveillance is a non-invasive strategy designed to identify a minority of patients with low-risk papillary thyroid carcinoma who might experience clinical progression and benefit from additional definitive treatments. Global experience suggests that these tumors typically show minimal changes in size during active surveillance, often demonstrating very slow growth or even size reduction. Moreover, the rate of lymph node metastases is low and can be effectively managed through rescue surgery, without impacting cancer-related mortality. However, despite 30 years of experience demonstrating the safety and feasibility of active surveillance for appropriately selected patients, this approach seems to have limited adoption in specific contexts. This limitation can be attributed to various barriers, including disparities in access to accurate information about the indolent nature of this disease and the prevalence of a maximalist mindset among certain patients and medical settings. This review aims to revisit the experience from the last three decades, provide current insights into the clinical outcomes of active surveillance trials, and propose a systematic approach for its implementation. Furthermore, it intends to emphasize the importance of precise patient selection and provides new perspectives in the field.

Thyroid cancer in pregnancy: diagnosis, management, and treatment

The evaluation and management of cancer during pregnancy requires special care to assure the health and safety of both the mother and fetus. The diagnosis and treatment of thyroid cancer in the non-pregnant patient often involves radioactive iodine exposure. However, radioactive iodine is contraindicated in pregnancy and surgical interventions pose risks to both the mother and fetus. Thus, the management of thyroid cancer during pregnancy is a unique clinical challenge. In this review, we discuss the imaging of thyroid nodules during pregnancy, including the role of CT, MRI, and nuclear Imaging, as well as that of Ultrasound and FNA. The staging and prognosis are discussed along with the management, treatment, and surveillance of thyroid cancer in pregnancy. Finally, the risks to the fetus through treatment are examined. Case examples are provided with an emphasis on the appropriate direction of care from a radiologist's perspective.

A practical approach to the management of thyroid dysfunction during pregnancy

Pregnancy has an important impact on the thyroid gland and its function. Thyroid activity changes as a consequence of the novel physiological state of pregnancy and requires a complex hormonal and metabolic adaptation, which is possible only in the presence of a perfectly functioning thyroid gland. In fact, thyroid function is crucial for the success of the implantation and the progression of pregnancy. Abnormal thyroid function is very common among childbearing age women, explaining the high incidence of thyroid diseases that occur during pregnancy. Aim of this work is to analyze the adaptive events that characterize the thyroid function during pregnancy, exploring their hormonal, metabolic and molecular mechanisms. Moreover, the interpretation of the laboratory data necessary to monitor the thyroid functioning during normal pregnancy or in the presence of thyroid abnormalities will be discussed.

Retrospective Analysis of the Development of Human Thyroglobulin during Pregnancy in Patients with Treated Non-Recurrent Differentiated Thyroid Cancer

Aim: Therapy success in patients with differentiated thyroid cancer (DTC) after thyroidectomy and radioiodine therapy (RIT) is proven by permanent decrease in human thyroglobulin (hTg) to <1 ng/mL. In this retrospective analysis hTg development before, during and after pregnancy were analyzed. Material and methods: A descriptive analysis of hTg courses in 47 women with 57 pregnancies under levothyroxine substitution was performed after treatment of DTC without evidence of residual or recurrent disease. We compared hTg levels before, during and after pregnancies. A median of four measurements were performed during pregnancy. Results: In five out of the 47 patients at least one hTg increase to ≥1.0 ng/mL occurred during pregnancy (P1: 1.1; P2: 1.75; P3: 1.0; P4: 1.1; P5: 1.07 ng/mL). In another three cases an increase to ≥0.5 ng/mL occurred. After delivery, all patients returned to undetectable hTg levels. Human Tg maxima during pregnancy were significantly elevated according to Friedman´s Chi2 and p Holm−Bonferroni. Conclusion: In women with ablative thyroid therapy after DTC, a temporary elevation in hTg levels during pregnancy may occur. The reason therefore remains unclear and requires further investigation.

Assessment and treatment of thyroid disorders in pregnancy and the postpartum period

Thyroid disorders are prevalent in pregnant women. Furthermore, thyroid hormone has a critical role in fetal development and thyroid dysfunction can adversely affect obstetric outcomes. Thus, the appropriate management of hyperthyroidism, most commonly caused by Graves disease, and hypothyroidism, which in iodine sufficient regions is most commonly caused by Hashimoto thyroiditis, in pregnancy is important for the health of both pregnant women and their offspring. Gestational transient thyrotoxicosis can also occur during pregnancy and should be differentiated from Graves disease. Effects of thyroid autoimmunity and subclinical hypothyroidism in pregnancy remain controversial. Iodine deficiency is the leading cause of hypothyroidism worldwide. Despite global efforts to eradicate iodine deficiency disorders, pregnant women remain at risk of iodine deficiency due to increased iodine requirements during gestation. The incidence of thyroid cancer is increasing worldwide, including in young adults. As such, the diagnosis of thyroid nodules or thyroid cancer during pregnancy is becoming more frequent. The evaluation and management of thyroid nodules and thyroid cancer in pregnancy pose a particular challenge. Postpartum thyroiditis can occur up to 1 year after delivery and must be differentiated from other forms of thyroid dysfunction, as treatment differs. This Review provides current evidence and recommendations for the evaluation and management of thyroid disorders in pregnancy and in the postpartum period.

Physiological changes in pregnancy and their influence on the endocrine investigation

BACKGROUND

Physiological changes in pregnancy may result in significant alterations in endocrine hormone profiles, serum and urine electrolytes and endocrine gland morphology on imaging. Pregnancy-specific pathophysiological processes may also affect the results for endocrine tests. Investigation of endocrine disorders in pregnancy requires knowledge of these changes and awareness of the safety of dynamic hormone testing and imaging for the mother and foetus.

OBJECTIVE

This review seeks to outline the important physiological changes in pregnancy affecting reference intervals of basal and dynamic endocrine tests in pregnancy and the scenarios in which these changes are clinically significant, the pregnancy-specific disorders that may affect the investigation of endocrine disorders, and the safety of dynamic testing and imaging.

CONCLUSION

Awareness of the effect of physiological changes, and the potential impact of pregnancy-specific disorders of endocrine tests, and the safety of imaging is crucial to the management of endocrine disorders in pregnancy.

Active Surveillance as an Effective Management Option for Low-Risk Papillary Thyroid Microcarcinoma

Active surveillance (AS) for low-risk papillary thyroid microcarcinoma (PTMC) has been accepted worldwide as safe and effective. Despite the growing acceptance of AS in the management of low-risk PTMCs, there are barriers to AS in real clinical settings, and it is important to understand and establish appropriate AS protocol from initial evaluation to follow-up. PTMC management strategies should be decided upon after careful consideration of patient and tumor characteristics by a multidisciplinary team of thyroid cancer specialists. Patients should understand the risks and benefits of AS, participate in decision-making and follow structured monitoring strategies. In this review, we discuss clinical outcomes of AS from previous studies, optimal indications and follow-up strategies for AS, and unresolved questions about AS.

Thyroid disorders in subfertility and early pregnancy

Disorders of thyroid function are common in pregnancy and have implications for foetal and maternal health. Thyroid autoimmunity, as evidenced by the presence of elevated levels of anti-thyroid antibodies (anti-TPO and anti-Tg antibodies) is associated with an increased risk of miscarriage, though the mechanism remains poorly understood. There has been considerable focus on the implications and optimal management of pregnant women with thyroid disease, especially those undergoing assisted reproduction. Pregnancy results in significant changes in thyroid physiology and these need to be understood by clinicians involved in the care of pregnant women. Guidelines for the use of thyroxine and target thyroid function tests have been produced by international bodies but it is recognised that these predominantly reflect expert opinion rather than established evidence-based practice. Importantly a number of key clinical trials have been performed to aid understanding, particularly of the consequences of hypothyroidism for mother and baby, and the effectiveness of thyroid hormone use in autoimmune and subclinical hypothyroidism. This review summarises the current knowledge base and guidance for practice relating to thyroid disorders in pregnancy and subfertility.

Active Surveillance for Small Papillary Thyroid Cancer: A Systematic Review and Meta-Analysis

Background: The rapid increase in the incidence of small papillary thyroid carcinoma (PTC) appears to be caused by the detection of small thyroid cancers. Active surveillance (AS) was therefore suggested to overcome this problem. As the results were favorable with low rates of size enlargement and lymph metastasis, the 2015 American Thyroid Association Management Guidelines endorsed AS as an alternative to immediate surgery. As the clinical value of AS is a subject of ongoing active discussions and surveys, we considered a systematic review and meta-analysis to be timely and necessary. Methods: Ovid-MEDLINE and EMBASE databases were searched up to January 5, 2019, for studies reporting patients who were followed up with AS for PTC. Data extraction and methodological quality assessment were performed independently by two radiologists. The primary outcomes were to identify the annual pooled proportions of size enlargement of 3 mm or more and the detection of lymph node metastases at a 5-year follow-up period. These were calculated using an inverse-variance weighting model. An additional outcome was evaluation of the reasons for surgery during AS. Results: The pooled proportion of size enlargement occurring at 5 years was 5.3% [95% confidence interval (CI), 4.4-6.4%], and the pooled proportion of 5-year lymph node metastasis was 1.6% [CI, 1.1-2.4%]. In many subjects undergoing delayed operations, the reasons for operation were often other than those of size enlargement or lymph node metastasis. Conclusions: AS is effective for the management of small PTC, with a low proportion of size enlargement or lymph node metastasis occurring at 5 years. However, a substantial proportion of the causes of delayed surgery were other than size enlargement or lymph node metastasis, and these situations need to be optimally managed.

Active Surveillance of Low-Risk Papillary Thyroid Microcarcinoma: A Multi-Center Cohort Study in Korea

BACKGROUND

Active surveillance has been introduced as a management option for low-risk papillary thyroid microcarcinoma (PTMC) due to its mostly indolent course.

METHODS

This was a multicenter study of 370 PTMC patients who underwent active surveillance more than one year. The changes in volume and maximum diameter between initial and last ultrasonography were evaluated to identify the natural course of PTMC during active surveillance.

RESULTS

Patients' age at diagnosis was 51 ± 12 years, and 110 (30%) patients were <45 years of age. The initial maximum diameter and volume of PTMCs were 5.9 ± 1.7 mm and 81.0 ± 77.7 mm³, respectively. During the median 32.5 months of follow-up, 86 (23.2%) patients were found to have an increase in tumor volume, and 13 (3.5%) patients showed an increase in the maximal diameter of the tumor. The cumulative incidence of volume increase gradually rose with time (6.9%, 17.3%, 28.2%, and 36.2% after two, three, four, and five years, respectively). The risk of volume increase in patients <45 years of age was twice as high as in older patients (p = 0.002). There was no significant difference in tumor size change according to sex, levothyroxine treatment, or presence of Hashimoto's thyroiditis. During the period, 58 (15.7%) patients underwent delayed thyroid surgery due to anxiety (37.9%), tumor size increase (32.8%), or appearance of cervical lymph node metastasis (8.6%). Lymph node metastasis was found in 29.3% of patients on pathological examination.

CONCLUSIONS

A significant number of PTMCs grow during active surveillance, and tumor volume change is a more sensitive means of evaluating tumor growth. Active surveillance can be carefully applied for selected patients. Although it is not contraindicated, it should be applied more cautiously for younger patients.

Pregnancy as a risk factor for thyroid cancer progression

PURPOSE OF REVIEW

The current review evaluates the impact of pregnancy on women with thyroid cancer in three different clinical situations: those with newly diagnosed differentiated thyroid cancer (DTC), those under active surveillance for papillary thyroid microcarcinomas (PMCs), and those with previously treated DTC.

RECENT FINDINGS

Recent pregnancy is not associated with high-risk pathological features of DTC. In women with known PMCs under active surveillance, pregnancy does not increase the risk of disease progression. Thus, deferring surgery for newly diagnosed DTC or known PMCs until after delivery is safe for both mother and the unborn child. If a woman with previously treated DTC is planning pregnancy, response-to-therapy status is an excellent guide for predicting pregnancy-associated disease progression or recurrence.

SUMMARY

Clinical studies consistently show that pregnancy is not associated with significant disease progression in newly diagnosed thyroid cancer, PMCs under active surveillance, or previously treated DTC.

Comparison of Immunohistochemistry and Direct Sanger Sequencing for Detection of the BRAF(V600E) Mutation in Thyroid Neoplasm

BACKGROUND

The BRAF(V600E) mutation is the most common genetic alteration identified in papillary thyroid carcinoma (PTC). Because of its costs effectiveness and sensitivity, direct Sanger sequencing has several limitations. The aim of this study was to evaluate the efficiency of immunohistochemistry (IHC) as an alternative method to detect the BRAF(V600E) mutation in preoperative and postoperative tissue samples.

METHODS

We evaluated 71 patients who underwent thyroid surgery with the result of direct sequencing of the BRAF(V600E) mutation. IHC staining of the BRAF(V600E) mutation was performed in 49 preoperative and 23 postoperative thyroid specimens.

RESULTS

Sixty-two patients (87.3%) had PTC, and of these, BRAF(V600E) was confirmed by direct sequencing in 57 patients (91.9%). In 23 postoperative tissue samples, the BRAF(V600E) mutation was detected in 16 samples (70%) by direct sequencing and 18 samples (78%) by IHC. In 24 fine needle aspiration (FNA) samples, BRAF(V600E) was detected in 18 samples (75%) by direct sequencing and 16 samples (67%) by IHC. In 25 core needle biopsy (CNB) samples, the BRAF(V600E) mutation was detected in 15 samples (60%) by direct sequencing and 16 samples (64%) by IHC. The sensitivity and specificity of IHC for detecting the BRAF(V600E) mutation were 77.8% and 66.7% in FNA samples and 99.3% and 80.0% in CNB samples.

CONCLUSION

IHC could be an alternative method to direct Sanger sequencing for BRAF(V600E) mutation detection both in postoperative and preoperative samples. However, application of IHC to detect the BRAF(V600E) mutation in FNA samples is of limited value compared with direct sequencing.

Preoperative Clinical and Sonographic Predictors for Lateral Cervical Lymph Node Metastases in Sporadic Medullary Thyroid Carcinoma

BACKGROUND

Total thyroidectomy and cervical lymph node (LN) dissection is generally recommended in patients with medullary thyroid carcinoma (MTC). However, there is no clear evidence for whom to perform prophylactic lateral neck dissection in MTC patients without evident lateral cervical lymph node (LCLN) metastasis in preoperative images. This study evaluated the preoperative features for predicting the LCLN metastasis of MTC.

METHODS

The study included 26 MTC patients with LCLN metastasis at initial surgery (N1b group) and 47 MTC patients without any LN metastasis or recurrence of disease (N0-NED group). The association between LCLN metastasis and preoperative clinical and sonographic characteristics (size, location, solid component, shape, margin, echogenicity, calcification, and subcapsular location of the tumor) were evaluated.

RESULTS

There were no significant differences in age and sex between the N1b and N0-NED groups. Preoperative serum levels of calcitonin >65 pg/mL were associated with LCLN metastasis (p < 0.001). In preoperative neck ultrasonography (US), patients in the N1b group were more commonly found with a larger tumor (>1.5 cm) of irregular shape with a spiculated margin and a subcapsular location than those in the N0-NED group (p = 0.029, p < 0.001, p < 0.001, and p < 0.001, respectively). Increases in the number of these LCLN metastasis-related features were significantly associated with higher risk for LCLN metastasis (p < 0.001). The presence of two or more predictors was an appropriate cutoff point for predicting LCLN metastasis of MTC with 73.1% sensitivity and 91.5% specificity.

CONCLUSIONS

MTC tumors with high preoperative calcitonin levels (>65 pg/mL), larger size (>1.5 cm), irregular shape, spiculated margins, and subcapsular locations in the neck US are at higher risk for LCLN metastasis. MTC patents with fewer than two predictors might be suitable for treatment without prophylactic LCLN dissection.

High Serum TSH Level Is Associated With Progression of Papillary Thyroid Microcarcinoma During Active Surveillance

OBJECTIVE

Thyroid-stimulating hormone (TSH) is a growth factor affecting initiation or progression of papillary thyroid cancer (PTC), which supports TSH suppressive therapy in patients with PTC. In patients with papillary thyroid microcarcinoma (PTMC) during active surveillance, however, the association between serum TSH level and growth of PTMC has not been demonstrated.

PATIENTS

We analyzed 127 PTMCs in 126 patients under active surveillance with serial serum TSH measurement and ultrasonography.

DESIGN

The patients were categorized into groups with the highest, middle, and lowest time-weighted average of TSH (TW-TSH). PTMC progression was defined as a volume increase of ≥50% compared with baseline. Kaplan-Meier survival analysis according to TW-TSH groups and Cox proportional hazard modeling was performed. We identified the cutoff point for TSH level by using maximally selected log-rank statistics.

RESULTS

During a median follow-up of 26 months, PTMC progression was detected in 28 (19.8%) patients. Compared with the lowest TW-TSH group, the adjusted hazard ratio (HR) for PTMC progression in the highest TW-TSH group was significantly higher [HR 3.55; 95% confidence interval (CI), 1.22 to 10.28; P = 0.020], but that in the middle TW-TSH group was not (HR 1.52; 95% CI, 0.46 to 5.08; P = 0.489). The cutoff point for the serum TSH level for PTMC progression was 2.50 mU/L.

CONCLUSIONS

Sustained elevation of serum TSH levels during active surveillance is associated with PTMC progression. Maintaining a low-normal TSH range with levothyroxine treatment during active surveillance of PTMC might be considered in future studies.

Recent Pregnancy Is Not Associated with High-Risk Pathological Features of Well-Differentiated Thyroid Cancer

BACKGROUND

Thyroid cancer is commonly diagnosed in the first postpartum year, supporting the theory that high levels of estrogen may stimulate progression of hormone-mediated thyroid cancer. The aim of this study was to assess the effect of recent pregnancy on histopathologic disease characteristics of well-differentiated thyroid cancer (WDTC).

METHODS

Cases of WDTC (1999-2012) were identified from the California Cancer Registry and linked to data from the Office of Statewide Health Planning and Development. Using a matched control design, recently pregnant women (pregnancy up to five years before and nine months after a thyroid cancer diagnosis) were compared with non-pregnant controls matched by age and race/ethnicity. The main outcome measures were histopathologic tumor characteristics (tumor size, extrathyroidal extension, and nodal metastases), disease status at last follow-up, and five-year disease-specific survival.

RESULTS

The study sample of 1204 women (M_age ± standard deviation = 30.9 ± 5.5 years; 46.5% Caucasian and 40.0% Hispanic) included 301 recently pregnant women matched against 903 non-pregnant controls. Comparing recently pregnant versus non-pregnant women, no significant differences were observed with respect to tumor size (M = 2.2 ± 1.6 vs. 2.3 ± 3.9 cm; p = 0.39), extrathyroidal extension (12.0% vs. 14.1%; p = 0.46), stage at diagnosis (localized disease: 67.4% vs. 62.8%; regional metastases: 30.6% vs. 33.4%; distant metastases: 2.0% vs. 3.8%; p = 0.17), disease status at last follow-up (free of tumor vs. not free of tumor; p = 0.48), and five-year disease-specific survival (99.5% vs. 99.5%). In multivariate analyses, after controlling for patient age and ethnicity, recent pregnancy was not a significant predictor of tumor size, extrathyroidal extension, nodal metastases, or distant metastases.

CONCLUSIONS

In this cohort, recent pregnancy was not associated with high-risk pathological features of differentiated thyroid cancer. These findings provide reassurance with regards to the concern that pregnancy may act as a potential stimulus for thyroid cancer growth.