Comparison of histopathological features and prognosis of classical and follicular variant papillary thyroid carcinoma

Comparison of Treatment and Prognosis Between Follicular Variant Papillary Thyroid Carcinoma and Classical Papillary Thyroid Carcinoma

This cohort study evaluated the associations of different treatments with the prognosis of follicular variant papillary thyroid carcinoma (FVPTC) and classical papillary thyroid carcinoma (CPTC) patients. The data of 69034 PTC patients were retrieved from the Surveillance, Epidemiology, and End Results (SEER) database. The 5-year mortality of CPTC and FVPTC patients receiving surgery, radiation and combination therapy were compared. The univariable and multivariable cox proportional risk models explored the associations between different treatments and the 5-year mortality in CPTC and FVPTC patients. The 5-year mortality of CPTC patients was 2.81% and FVPTC patients was 2.47%. Compared with CPTC receiving lobectomy and/or isthmectomy, those not receiving surgery were associated with increased risk of 5-year mortality [Hazards ratio (HR)=3.27, 95% confidence interval (CI): 2.55-4.20] while total thyroidectomy was correlated with reduced risk of 5-year mortality (HR=0.67, 95%CI: 0.55-0.80). Radioactive iodine (RAI) was linked with decreased risk of 5-year mortality in CPTC patients (HR=0.57, 95%CI: 0.50-0.65). CPTC patients undergoing both surgery and radiation were related to decreased risk of 5-year mortality compared with those receiving surgery only (HR=0.55, 95%CI: 0.48-0.63). CPTC patients receiving neither surgery nor radiation (HR=4.53, 95%CI: 3.72-5.51) or those receiving radiation (HR=1.98, 95%CI: 1.13-3.48) were correlated with elevated risk of 5-year mortality. The elevated risk of 5-year mortality in FVPTC patients was reduced in those undergoing RAI (HR=0.63, 95%CI: 0.51-0.76). In conclusion, combination therapy was associated with decreased risk of 5-year mortality in CPTC and FVPTC patients, which might provide a reference for the management of these patients.

The Role of American Thyroid Association Pediatric Thyroid Cancer Risk Stratification and BRAFV600E Mutation in Predicting the Response to Treatment in Papillary Thyroid Cancer Patients ≤18 Years Old

OBJECTIVE

This study aimed to evaluate the role of risk stratification by the American Thyroid Association (ATA) pediatric thyroid cancer risk levels and BRAF^V600E mutation to predict the response to treatment in papillary thyroid cancer (PTC) patients ≤18 years old.

METHODS

Clinical outcomes during a median period of 6 (2-21.8) years were assessed in 70 patients, according to ATA pediatric risk stratification, BRAF^V600E mutation status, and dynamic risk stratification (DRS) at final follow-up.

RESULTS

Of 70 patients, 44 (63%), 14 (20%), and 12 (17%) were classified initially as low-, intermediate-, and high-risk, respectively. BRAF^V600E mutation analysis data was available in 55 (78.6%) patients, of whom 18 (32.7%) had the BRAF^V600E mutation. According to the final DRS, 61 (87%), two (3%), six (9%), and one (1%) patients were classified as an excellent, incomplete biochemical, incomplete structural, and indeterminate response, respectively. All ATA low-risk patients showed excellent response to treatment, whereas the rate of excellent response was 65.4% in intermediate- and high-risk levels (p<0.001). The rates of excellent response in BRAF^V600E positive and negative patients were 83% and 92%, respectively (p=0.339). The rate of locoregional recurrence was significantly higher in BRAF^V600E positive vs negative patients (33.3% vs 2.7% respectively, p=0.001).

CONCLUSION

ATA pediatric risk stratification is effective in predicting response to treatment in PTC patients ≤18 years old. The presence of BRAF^V600E mutation was highly predictive for recurrence but had no significant impact on the rate of excellent response to treatment at final follow-up.

Ablation therapy using a low dose of radioiodine may be sufficient in low- to intermediate-risk patients with follicular variant papillary thyroid carcinoma

OBJECTIVES

Follicular variant papillary thyroid carcinoma (FVPTC) is treated similarly to classical variant papillary thyroid carcinoma (cPTC). However, FVPTC has unique tumour features and behaviours. We investigated whether a low dose of radioiodine was as effective as a high dose for remnant ablation in patients with FVPTC and evaluated the recurrence of low-intermediate risk FVPTC.

METHODS

Data from cPTC and FVPTC patients treated with I-131 from 2004 to 2014 were reviewed. Demographics, tumour behaviour, lymph node metastasis, and local recurrence data were compared between FVPTC and cPTC patients. Then, low-intermediate risk FVPTC patients were divided into low, intermediate, and high I-131 dose groups, and postoperative I-131 activities were analysed to evaluate the effectiveness of I-131 therapy for thyroid remnant ablation.

RESULTS

In total, 799 cases of FVPTC (n = 168) and cPTC (n = 631) treated with I-131 were identified. Patients with FVPTC had a larger primary nodule size than cPTC, but lymph node metastases and local recurrence were more prevalent in cPTC than in FVPTC. For the low-, intermediate-, and high-dose groups, success rates of ablation did not differ (82.0%, 80%, and 81.3%, respectively).

CONCLUSION

FVPTC differs from cPTC in behaviour. Low-dose ablation may be sufficient in FVPTC patients with low-intermediate disease risk.

Radioactive iodine therapy may not improve disease-specific survival in follicular variant papillary thyroid cancer without distant metastasis: A propensity score-matched analysis

BACKGROUND

Whether radioactive iodine (RAI) therapy is effective in improving disease-specific survival (DSS) in patients with follicular variant papillary thyroid cancer (FVPTC) without distant metastasis remains unclear.

METHODS

Patients with FVPTC were identified from the Surveillance, Epidemiology, and End Results (SEER) database between 2004 and 2015. The Kaplan-Meier method and the Cox proportional hazards regression model were used to evaluate DSS. Propensity score-matched analysis was performed to reduce the influence of confounding bias.

RESULTS

RAI did not improve DSS, even in patients with aggressive features such as T4 classification (p = 0.658), extrathyroidal extension (p = 0.083), lateral lymph node metastasis (p = 0.544), and ≥5 metastatic lymph nodes (p = 0.599).

CONCLUSION

RAI did not affect DSS in patients with FVPTC without distant metastases in this SEER database study. Multicenter, prospective studies including recurrence and molecular information should be conducted to comprehensively evaluate the effects of RAI on FVPTC.

Outcome of classical (CVPTC) and follicular (FVPTC) variants of papillary thyroid cancer: 15 years of follow-up

PURPOSE

To compare the epidemiological, clinical, and pathological features of follicular (FVPTC) and classical (CVPTC) variants of papillary thyroid cancer and to correlate their outcomes according to different features.

METHODS

Retrospective analysis of FVPTC and CVPTC patients selected at the moment of surgical treatment from 1999 to 2004, with a median follow-up of 15 years.

RESULTS

Several significant differences were found between FVPTC and CVPTC such as the mean age at diagnosis, the presence of tumor capsule, the presence of thyroid capsule invasion, the presence of perithyroid soft tissue invasion, the lymph node metastases, the multifocality and bilaterality. At the end of follow-up only 9% (77/879) patients were not cured. However, a statistically significant lower percentage of persistent disease was found in the FVPTC than in the CVPTC group (3% vs. 14.5%, respectively, p < 0.0001). In multivariate analysis, the absence of the tumor capsule (OR = 6.75) or its invasion (OR = 7.89), the tumor size ≥4 cm (OR = 4.29), the variant CVPTC (OR = 3.35), and the presence of lymph node metastases (OR = 3.16) were all independent risk factors for the persistence of the disease.

CONCLUSIONS

Despite an overall excellent prognosis of both variants, a higher percentage of CVPTC than FVPTC patients had a persistent disease. The absence of tumor capsule or its invasion, the tumor size ≥4 cm and the presence of lymph node metastases are other prognostic factors for the persistence of the disease. In contrast, the presence of an intact tumor capsule is the only good prognostic factor for their outcome.

Is a simplified TNM staging system more clinically relevant than the American Joint Committee on Cancer system for the follicular variant of papillary thyroid cancer?

Background

Despite the recent release of the 8th edition of the American Joint Committee on Cancer (AJCC) staging manual, risk stratification for the follicular variant of papillary thyroid cancer (FVPTC), which is the second common variant of papillary thyroid carcinoma (PTC) after classical PTC, remains controversial. This study aimed to develop a more accurate and relevant staging system specifically for FVPTC.

Methods

Patients with FVPTC who were included in the Surveillance, Epidemiology, and End Results (SEER) open database between 2010 and 2015 were divided into 47 groups according to their TNM classifications and age. Subsequently, these 47 groups were categorized into appropriate stages based on Kaplan-Meier survival curves, mortality analyses, a Cox proportional hazards model, and clinical considerations.

Results

Our retrospective analysis of 17,628 cases yielded the following new staging classification: stage I, defined as age <55 years and any T/N/M or age ≥55 years and T1-3/any N/M0 (n=17,427, 98.85%); stage II, age ≥55 and T4/any N/M0 or age ≥55 and any T/N0/M1 (n=173, 0.99%); and stage III, age ≥55 and any T/N1/M1 (n=28, 0.16%). The overall mortality rates per 1,000-person-years were 4.135 [95% confidence interval (CI): 3.653–4.681], 71.193 (95% CI: 51.354–98.697), and 199.744 (95% CI: 115.983–343.997) for our new stages I, II, and III, respectively. The hazard ratios for the new stages II and III (reference: stage I) were 5.081 (95% CI: 3.110–8.301) and 21.690 (95% CI: 11.402–41.258), respectively.

Conclusions

Compared to the 8th edition of the AJCC staging system, our newly proposed system provided more accurate risk stratification for patients with FVPTC, as demonstrated by actual survival and mortality outcomes. This new model may thus help guide more personalized treatment for these patients.

A Mobile App for Thyroid Cancer Patients Aiming to Enhance Their Quality of Life: Protocol for a Quasiexperimental Interventional Pilot Study

Background

Thyroid cancer (TC) is one of the fastest growing cancers all over the world. Differentiated thyroid cancer (DTC) is the most frequent subtype of TC. When appropriate treatment is given, the prognosis for the patient is generally excellent. Despite the generally good prognosis of thyroid carcinomas, the symptoms may range from emotional to physical discomfort, depending on the thyroid hormone status, which can severely affect the patient. Moreover, the diagnostic and therapeutic procedures that DTC patients have to undergo, such as thyroidectomy and radioiodine therapy, significantly affect their mental and physical well-being. Often, the physician only addresses the favorable prognosis of DTC compared with other cancer types and neglects to assess issues related to the quality of life (QoL) of the patient; this was the reason we decided to design a mobile app for DTC patients and their caregivers.

Objective

The aim of this study is to research the feasibility and applicability of an mHealth app tailored to DTC patients, as reflected in their QoL. The main features of the developed app offer access to useful information about thyroid cancer, diagnostic tests, and the appropriate therapy administered to DTC patients.

Methods

Based on the existing literature, we created an up-to-date information platform regarding TC and especially DTC. In order to develop an effective app that can be implemented in current health care, we designed a section where the patient and physician can keep a medical record in an effort to enable access to such information at any time. Finally, we designed a user-friendly notification program, including pill prescription, follow-up tests, and doctor visit reminders in order to equally facilitate the lives of the patient and physician.

Results

Having developed this mobile app, we aim to conduct a pilot quasiexperimental interventional trial. Our intention is to enroll at least 30 TC patients and assign them to intervention or control groups. Both groups will receive standard care for treating and monitoring TC, and the intervention group will also receive and use the DTC app. TC patients’ QoL will be assessed for both control and intervention groups in order to examine the effectiveness of the DTC app. QoL will be assessed through the QoL core questionnaire European Organisation for Research and Treatment of Cancer (EORTC) QLQ-THY34 in combination with the EORTC QLQ-C30 questionnaire through quantitative statistical analysis.

Conclusions

The use of mHealth apps can play a significant role in patient education, disease self-management, remote monitoring of patients, and QoL improvement. However, the main limitation of the majority of existing studies has been the lack of assessing their usefulness as well as the absence of specific instruments to carry out this assessment. In light of those considerations, we developed a mobile app tailored to the needs of DTC patients. Furthermore, we evaluated its contribution to the QoL of the patients by using the EORTC QLQ-THY34 questionnaire, an accurate and safe instrument for the evaluation of the QoL in TC patients, while supporting future planned endeavors in the field.

International Registered Report Identifier (IRRID)

PRR1-10.2196/13409

Differentiation of the Follicular Variant of Papillary Thyroid Carcinoma From Classic Papillary Thyroid Carcinoma: An Ultrasound Analysis and Complement to Fine-Needle Aspiration Cytology

OBJECTIVES

It is difficult to establish a diagnosis of the follicular variant of papillary thyroid carcinoma (PTC) using fine-needle aspiration cytology (FNAC). Preoperative features on ultrasound (US) imaging are different between follicular PTC and classic PTC. This study developed a risk score system to differentiate follicular PTC from classic PTC and to correlate the risk score of follicular PTC with its FNAC categories and pathologic features.

METHODS

The US features, FNAC results, and pathologic reports of 156 follicular PTC nodules and 152 classic PTC nodules from 296 patients with PTC along with their clinical characteristics were reviewed retrospectively. A risk score system based on US features was developed by multivariate logistic regression to differentiate classic PTC from follicular PTC nodules. The risk scores were then correlated with the FNAC category and pathologic features of the nodules.

RESULTS

The US risk score (5 × echogenicity + 3 × calcifications + 3 × marginal regularity) had an area under the receiver operating characteristic curve of 0.85 and a cutoff value of 8.0, with specificity of 87% and sensitivity of 69% for predicting a classic PTC nodule. The follicular PTC nodules with low Bethesda categorization (I-III) had a median US risk score of 6 (range, 0-11), which was higher than that of nodules with high categorization (IV-VI; median, 3; range, 0-11).

CONCLUSIONS

The US risk score may be useful in differentiating classic PTC from follicular PTC and complementary to FNAC in identifying follicular PTC.

Construction and investigation of lncRNA-associated ceRNA regulatory network in papillary thyroid cancer

Increasing evidence has experimentally proved the competitive endogenous RNA (ceRNA) hypothesis that long non-coding RNA (lncRNA) can affect the expression of RNA targets by competitively combining microRNA (miRNA) via miRNA response elements. However, an extensive ceRNA network of thyroid carcinoma in a large cohort has not been evaluated. We analyzed the RNAseq and miRNAseq data of 348 cases of primary papillary thyroid cancer (PTC) patients with clinical information downloaded from The Cancer Genome Atlas (TCGA) project to search for potential biomarkers or therapeutic targets. A computational approach was applied to build an lncRNA-miRNA-mRNA regulatory network of PTC. In total, 780 lncRNAs were detected as collectively dysregulated lncRNAs in all 3 PTC variants compared with normal tissues (fold change >2 and false discovery rate <0.05). The interactions among 45 lncRNAs, 13 miRNAs and 86 mRNAs constituted a ceRNA network of PTC. Nine out of the 45 aberrantly expressed lncRNAs were related to the clinical features of PTC patients. However, the expression levels of 3 lncRNAs (LINC00284, RBMS3-AS1 and ZFX-AS1) were identified to be tightly correlated with the patients overall survival (log-rank, P<0.05). The present study identified a list of specific lncRNAs associated with PTC progression and prognosis. This complex ceRNA interaction network in PTC may provide guidance for better understanding the molecular mechanisms underlying PTC.

Impact of major different variants of papillary thyroid microcarcinoma on the clinicopathological characteristics: the study of 1041 cases

Background

The incidence of papillary thyroid microcarcinoma (PTMC) has been increasing globally in the past few decades. PTMC does not have a distinctive morphology that results in differences in biological behavior. The aim of this study was to classify PTMCs according to the morphological features and explore the relationship with clinicopathological characteristics. Additionally, we sought to evaluate whether different variants of PTMC can be an independent predictor for lymph mode metastasis when considering other risk factors.

Methods

Between December 2014 and December 2015, 1041 PTMC cases undergoing surgical resection at Tianjin Medical University Cancer Institute and Hospital were reviewed retrospectively. Statistical analysis was performed to investigate the independent factors for lymph node metastasis in PTMC.

Results

Conventional variant PTMC (CPTMC), follicular variant PTMC (FPTMC), and encapsulated variant PTMC (EnPTMC) were major variants in PTMC, collectively accounting for 96.7% of the entire PTMC cohort.There were significant differences in clinicopathological characteristics among the three major variants. The frequency of aggressive parameters was significantly different among the three variants, including tumor size, minimal extrathyroidal extension (minimal ETE), and lymph node metastasis (all P < 0.05), being highest in CPTMC, lowest in EnPTMC, and intermediate in FPTMC. FPTMC (OR = 0.642, P = 0.003) and EnPTMC (OR = 0.540, P = 0.041) were independent protective factors for lymph node metastasis (LNM). In contrast, male gender (OR = 1.836, P = 0.000), age less than 45 years (OR = 1.457, P = 0.009), tumor size greater than 0.5 cm (OR = 1.453, P = 0.007), calcification (OR = 1.465, P = 0.016), minimal ETE (OR = 1.801, P = 0.001), and multifocality (OR = 1.721, P = 0.000) were independent risk factors for LNM.

Conclusions

The present study demonstrates the distinct biological behaviors of the three major PTMC variants and establishes an aggressive order of CPTMC ≫ FPTMC > EnPTMC. It is necessary to take into consideration variant-related risks and other independent predictors for the determination of lymphadenectomy in patients with PTMC.