Association of Multifocality With Prognosis of Papillary Thyroid Carcinoma: A Systematic Review and Meta-analysis

The significance and prognostic value of multifocal papillary thyroid carcinoma in children and adolescents

INTRODUCTION

The prognostic value of multifocality in paediatric papillary thyroid carcinoma (PTC) patients remains a subject of debate. This study aimed to explore the clinical significance and prognostic value of multifocality in children and adolescents with PTC.

METHODS

This study retrospectively analysed the clinicopathological characteristics and postoperative follow-up data of 338 PTC patients aged ≤ 20 years from May 2012 to July 2022. The clinical and pathological characteristics of 205 patients with unifocal lesions and 133 patients with multifocal lesions were compared. A logistic regression model evaluated the relationship between multifocal lesions and disease recurrence/persistence in children and adolescents with PTC. Based on the median follow-up time of children with multifocal PTC, 114 patients with multifocal PTC older than 20 years were added, and the clinicopathological characteristics were compared between the 133. paediatric/adolescent patients and 114 adult patients with multifocal PTC.

RESULTS

Among the paediatric and adolescent patients, over a median follow-up time of 49 months, 133 had multifocal disease and 205 had unifocal disease. Multifocal PTC patients exhibited stronger invasiveness in the form of extrathyroidal extension, tumour diameter, lymph node metastasis, and distant metastasis. Multifocality (OR 2.68; p = 0.017), lateral lymph node metastasis (OR 2.85; p = 0.036), and distant metastasis (OR 4.28; p = 0.010) were identified as independent predictive factors for the recurrence/persistence of disease. Comparing the paediatric/adolescent vs. adult multifocal patients, the former demonstrated greater tumour invasiveness. Lateral lymph node metastasis (OR 6.36; P = 0.012) and distant metastasis (OR 3.70; P = 0.027) were independent predictive factors for recurrence/persistence of disease in multifocal patients, while age was not (OR 0.95; P = 0.455).

CONCLUSION

Tumour multifocality independently predicts persistent/recurrent disease in paediatric and adolescent PTC patients.

Multifocal Papillary Thyroid Carcinomas With Discordant Molecular Drivers: Emphasizing the Morphology and Collision Tumors

Multifocal papillary thyroid carcinomas (PTCs) are common and the majority of the tumors harbor mutual BRAF p.V600E mutation. This study aimed to investigate a contemporary series of multifocal PTCs with discordant molecular drivers. Consecutive thyroidectomies diagnosed with multifocal PTCs ≥0.5 cm between 2019 and 2023 were reviewed. Immunohistochemistry (IHC) for BRAF VE1 was performed for all tumors. Cases with discordant BRAF IHC results or morphologic discrepancy were identified, and BRAF IHC-negative tumors were subjected to RAS Q61R IHC and/or targeted RNA next-generation sequencing. A total of 770 patients with a main PTC ≥0.5 cm were identified; 255 (33.1%) had multifocal disease, and 142 (18.4%) had at least another PTC ≥0.5 cm. Among them, 13 cases (9.2%, 13/142) had discordant molecular drivers. Twelve cases had one or more BRAF-positive PTCs accompanied by a BRAF-negative PTC (3 with CCDC6::RET fusion, 1 with NCOA4::RET fusion, 1 with ACBD5::RET fusion, 2 with ETV6::NTRK3 fusion, 1 with TG::FGFR1 fusion, 1 with LMTK2::BRAF fusion, 1 with AGK::BRAF fusion and RAS p.Q61R mutation, 1 with RAS p.Q61R mutation, and 1 without detectable molecular drivers). The last case had tumors with discordant fusion drivers (VIM::NTRK3 and TNS1::BRAF). Most cases showed tumors that were morphologically distinct (92.3%, 12/13) and occurred in the contralateral lobes (76.9%, 10/13). Notably, we identified 4 cases (30.8%) that presented as collision tumors and 6 cases (46.2%) that showed lymph node metastases, including 2 with simultaneous involvement by tumors with discordant molecular drivers, as novel findings. In summary, a subset (9.2%) of multifocal PTCs had discordant molecular drivers and 84.6% of them were a combination of BRAF-positive and kinase gene fusion-associated PTCs, most with distinct morphologies. Almost half of the cases had nodal metastasis and a third of them showed simultaneous involvement by tumors with discordant molecular drivers. The results highlight the clinical importance of identifying such cases, given the potentially different treatments.

Interplay of metabolic dysfunction-associated fatty liver disease and papillary thyroid carcinoma: insights from a Chinese cohort

PURPOSE

Thyroid cancer is one of a set of extrahepatic cancers that closely linked to metabolic dysfunction-associated fatty liver disease (MAFLD). However, the connection between MAFLD and the characteristics of papillary thyroid cancer (PTC) remains unexplored.

METHODS

Between Jan 2020 and Oct 2022, surgical cases of PTC patients were examined at the first Affiliated Hospital of Wenzhou Medical University. Clinical data extracted from the electronic medical system underwent a rigorous comparison between two groups, classified based on MAFLD criteria, using logistic regression analysis.

RESULTS

In this study of 4,410 PTC patients, 18.3% had MAFLD. MAFLD emerged as a distinct risk factor for lymph node metastasis (OR = 1.230, 95% CI 1.018-1.487) in this cohort, especially in females (OR = 1.321, 95% CI 1.026-1.702) and those with BMI ≥ 23 kg/m2 (OR = 1.232, 95% CI 1.004-1.511). The presence of MAFLD was found to significantly elevate the risk of BRAF V600E mutation in both subgroups characterized by FIB-4 score ≥ 1.3 (OR = 1.968, 95% CI 1.107-3.496) and BMI < 23 kg/m2 (OR = 2.584, 95% CI 1.012-6.601). Moreover, among the subset of individuals without non-alcoholic fatty liver disease (NAFLD), it was noted that MAFLD considerably increased the likelihood of tumor multifocality (OR = 1.697, 95% CI 1.111-2.592). Nevertheless, MAFLD did not exhibit any correlation with increased tumor size, extra-thyroidal extension (ETE), or later TNM stage in PTC.

CONCLUSION

In this cross-sectional study, we discovered a significant association between MAFLD and increased occurrences of lymph node metastasis. Furthermore, MAFLD was linked to a higher chance of BRAF V600E mutation and the presence of multiple tumors in certain subgroups.

Multi-UniFocality (MUF), in contrast to multifocality, in thyroid lesions: Relation to lymphocytic thyroiditis

Whereas multifocality typically concerns papillary thyroid carcinoma (PTC) without specification of intrathyroidal metastatic or independent nature of tumor foci, the designation of the latter as Multi-UniFocal (MUF) may be relevant for select cases. A case series involving multifocal thyroid lesions with divergent histopathological morphology and/or molecular profile, with molecular evaluation of multiple individual tumor foci per patient based on a next-generation sequencing approach, was retrospectively reviewed. Twenty-five patient cases with multifocal thyroid lesions suggestive of MUF, with 2-6 (median 3) tumor foci per patient, were described. Tumor lesions comprised diverse histopathology, including PTC, (E)FVPTC, NIFTP, FA, FTC, and oncocytic. Morphologically similar and/or diverse tumor foci harbored different molecular alterations (suggestive of non-shared clonality); with(out) coexistent similar foci harboring identical molecular alterations; or (partly) shared molecular alterations. MUF was associated with chronic lymphocytic thyroiditis in almost half of the cases. The recognition of MUF may justify the independent clinical consideration per individual tumor focus; as separate lesions albeit within a multifocal context. The potential clinical relevance and prognostic value of MUF remain to be further established.

Trends of the prevalence rate of central lymph node metastasis and multifocality in patients with low-risk papillary thyroid carcinoma after delayed thyroid surgery

Background

Active surveillance has been an option for patients with low-risk papillary thyroid carcinoma (PTC). However, whether delayed surgery leads to an increased risk of local tumor metastasis remain unclear. We sought to investigate the impact of observation time on central lymph node metastasis (CLNM) and multifocal disease in patients with low-risk PTC.

Methods

Patients who were diagnosed with asymptomatic low-risk PTC, and with a pathological maximum tumor size ≤1.5 cm by were included. The patients were classified into observation group and immediate surgery group, and subgroup analyses were conducted by observation time period. The prevalence of CLNM, lymph node (LN) involved >5, multifocal PTC and bilateral multifocal PTC were considered as outcome variables. The changing trend and risk ratio of prevalence over observation time were evaluated by Mann-Kendall trend test and Logistics regression.

Results

Overall, 3,427 and 1,860 patients were classified to the observation group and immediate surgery group, respectively. Trend tests showed that decreasing trends both on the prevalence of CLNM and LN involved >5 over the observation time, but the difference was not statistically significant, and the prevalence of multifocal PTC and bilateral multifocal PTC showed the significant decreasing trends. After adjustment, multivariate analysis showed no statistically significant difference between observed and immediate surgery groups in the four outcome variables.

Conclusion

In patients with subclinical asymptomatic low-risk PTC, observation did not result in an increased incidence of local metastatic disease, nor did the increased surgery extent in patients with delayed surgery compared to immediate surgery. These findings can strengthen the confidence in the active surveillance management for both doctors and patients.

Differentiated thyroid cancer: a focus on post-operative thyroid hormone replacement and thyrotropin suppression therapy

PURPOSE

This review focuses on post-operative thyroid hormone replacement and thyrotropin suppression therapy in patients with differentiated thyroid cancer.

METHODS

A clinical review.

RESULTS

Differentiated thyroid cancers (DTC), including papillary and follicular thyroid cancers, have an excellent prognosis and their management leverages a unique set of clinical tools arising from homology to the normal thyroid follicular cell. Surgery is the cornerstone of initial management, and post-operative care often requires thyroid hormone replacement therapy, which may be approached with the intent of physiologic normalization or used pharmacologically to suppress TSH as part of a DTC treatment.

CONCLUSION

Management of DTC and approaches to TSH suppression are tailored to an individual's risk of DTC recurrence and are adjusted to a patient's clinical status and comorbidities over time with the goal of mitigating risk and maximizing benefit.

Recurrence and survival for patients with thyroid carcinoma in the pediatric age group in the Emirate of Abu Dhabi: retrospective analysis of a multicentre cohort

OBJECTIVES

Pediatric thyroid cancer represents 2.3 % of thyroid cancers, and its long-term outcome data are sparse. There have not been studies in the UAE delineating its epidemiology, clinical and histological characteristics, and follow-up outcomes. We aimed to evaluate the clinical-pathological behavior, recurrence and survival rates in pediatrics with all types of thyroid cancer in the UAE.

METHODS

Multicentre retrospective chart review analysis of pediatric patients with thyroid carcinoma from January 2010 to December 2020 in Abu Dhabi, UAE.

RESULTS

Thirty-four patients were included, 85 % being females. Papillary thyroid carcinoma (PTC) was the commonest type of thyroid cancer (88 %) vs. follicular thyroid carcinoma (FTC) (11.8 %). Almost half of our patients had a multifocal disease, 26 % had lymphovascular invasion (LVI), and 21 % had extrathyroidal extension (ETE). There were no mortalities during follow-up. 85 % of patients exhibited complete remission, while 15 % of patients showed evidence of progressive residual or recurrent disease. One patient had metastasis to lymph nodes and lungs.

CONCLUSIONS

There were similar trends of incidence, sex prevalence, and histopathological patterns as the ones observed internationally. Potential risk factors in our population include a family history of thyroid cancer and obesity. The lower rate of ETE, LVI, metastasis, and recurrence indicates a possibly less aggressive disease.

Zwitterionic Injectable Hydrogel-Combined Chemo- and Immunotherapy Medicated by Monomolecular Micelles to Effectively Prevent the Recurrence of Tumor Post Operation

Surgical resection remains the most common method of tumor treatment; however, the high recurrence and metastasis after surgery need to be solved urgently. Herein, we report an injectable zwitterionic hydrogel based on "thiol-ene" click chemistry containing doxorubicin (DOX) and a macrophage membrane (MM)-coated 1-methyl-tryptophan (1-MT)-loaded polyamide-amine dendrimer (P-DOX/1MT) for preventing the postoperative recurrence of tumors. The results indicated that P-DOX/1MT@MM exhibited enhanced recognition and uptake of the dendrimer by tumor cells and induced the immunogenic cell death. In the mice tumor model, the P-DOX/1MT@MM-Gel exhibited high therapeutic efficiency, which could significantly reduce the recurrence of the tumor, including suppressing tumor growth, promoting dendritic cell maturation, and increasing tumor-infiltrating cytotoxic T lymphocytes. The mechanism analysis revealed that the hydrogel greatly reduces the side effects to normal tissues and significantly improves its therapeutic effect. 1MT in the hydrogel is released more rapidly, improving the tumor suppressor microenvironment and increasing the tumor cell sensitivity to DOX. Then, the DOX in the P-DOX/1MT@MM effectively eliminatedo the residual tumor cells and exerted enhanced toxicity. In conclusion, this novel injectable hydrogel that combines chemotherapy and immunotherapy has the property of sequential drug release and is a promising strategy for preventing the postoperative recurrence of tumors.

Total thyroidectomy versus unilateral lobectomy for unilateral multifocal papillary thyroid carcinoma: systematic review and meta‑analysis

The optimal surgical procedure(s) for unilateral multifocal papillary thyroid carcinomas is currently controversial. As such, the present study aimed to compare the efficacies of total thyroidectomy and lobectomy in patients with unilateral multifocal papillary thyroid carcinoma. A literature search of the PubMed/Medline, Embase, Web of Science, Cochrane Library, Wan Fang, and Zhi Wang databases for relevant studies, published from inception to October 31, 2022, was performed. Two researchers independently extracted data from the included studies. Lymph node metastasis, vocal fold paralysis, parathyroid injury, postoperative recurrence, and disease-free survival were evaluated. The meta-analysis included 7 studies comprising 1540 patients, of whom 496 and 1044 underwent lobectomy and total thyroidectomy, respectively. Compared with lobectomy, total thyroidectomy resulted in more vocal cord paralysis (odds ratio [OR] 0.35 [95% confidence interval (CI) 0.13 to 0.96]; P = 0.04) and parathyroid injury (OR 0.11 [95% CI 0.03-0.39]; P = 0.001) but with better disease-free survival (OR 0.21 [95% CI 0.09-0.49]; P = 0.000), although vocal cord paralysis and parathyroid injury, in large part, resolved within 1 year after surgery. In addition, there was no difference in postoperative lymph nodes metastasis (OR 0.74 [95% CI 0.13-4.21]; P = 0.737) and postoperative recurrence (OR 2.37 [95% CI 0.42-13.38]; P = 0.33). Excluding studies that deviated from the general trend, total thyroidectomy was beneficial in reducing recurrence. Compared with lobectomy, total thyroidectomy was beneficial in reducing recurrence and disease-free survival and may be considered a more optimal approach for unilateral multifocal papillary thyroid carcinoma.

Prognostic Value of Tumor Multifocality in Pediatric Papillary Thyroid Carcinoma: A Real-Life Multicentric Study

OBJECTIVE

To investigate the association of multifocality with clinical outcomes in pediatric papillary thyroid cancer.

STUDY DESIGN

Multicenter retrospective study of prospectively collected data.

SETTING

Tertiary referral center.

METHODS

This study included patients 18 years or younger who underwent total thyroidectomy and radioiodine ablation for papillary thyroid carcinoma (PTC) between 2005 and 2020 at 3 tertiary adult and pediatric hospitals in China. For disease-free survival (DFS), events were defined as persistent and/or recurrent diseases. The primary outcome was the association of tumor multifocality and DFS, assessed using Cox proportional hazards regression models.

RESULTS

One hundred and seventy-three patients (median age 16 years [range, 5-18 years]) were recruited. Multifocal diseases were seen in 59 patients (34.1%). After a median follow-up of 57 (range, 12-193 months) months, 63 (36.4%) patients had persistent diseases. There was a significant association between tumor multifocality and decreased DFS on univariable analysis (hazard ratio [HR] = 1.90, p = .01), yet it was nonsignificant after multivariate adjustment (HR = 1.20, p = .55). In a subgroup analysis of 132 pediatric patients with clinically M0 PTC, neither unadjusted HR (2.21, p = .06) nor adjusted HR (1.70, p = .27) of multifocal PTC was significantly higher in comparison to unifocal PTC.

CONCLUSION

In this highly selective surgical pediatric patient cohort with PTC, tumor multifocality was not an independent risk factor for decreased DFS.

Five-year Outcome Between Radiofrequency Ablation vs Surgery for Unilateral Multifocal Papillary Thyroid Microcarcinoma

CONTEXT

Ultrasound (US)-guided radiofrequency ablation (RFA) has been considered as an alternative to surgery or active surveillance for papillary thyroid microcarcinoma (PTMC). However, little is known about the long-term outcomes of RFA in comparison with surgery for unilateral multifocal PTMC.

OBJECTIVE

This work aims to report the comparison between RFA vs surgery for unilateral multifocal PTMC over a more than 5-year follow-up period.

METHODS

This was a retrospective study at a primary care center with a median follow-up period of 72.9 months. A total of 97 patients with unilateral multifocal PTMC were treated with RFA (RFA group, n = 44) or surgery (surgery group, n = 53). In the RFA group, patients were treated by a bipolar RFA generator and an 18-gauge bipolar RF electrode with a 0.9-cm active tip. In the surgery group, patients underwent thyroid lobectomy with prophylactic central neck dissection.

RESULTS

During the follow-up, no statistically significant differences were found in disease progression (4.5% vs 3.8%; P = ≥.999), lymph node metastasis (2.3% vs 3.8%; P = ≥.999), persistent lesion (2.3% vs 0%; P = .272), and RFS rates (97.7% vs 96.2%; P = .673) in the RFA and surgery groups. Patients undergoing RFA had a shorter hospitalization (0 vs 8.0 [3.0] d; P < .001), shorter procedure time (3.5 [2.4] vs 80.0 [35.0] min; P < .001), lower estimated blood loss (0 vs 20.0 [15.0] mL; P < .001), and lower costs ($1768.3 [0.1] vs $2084.4 [1173.8]; P = .001) than those in the surgery group. The complication rate in the surgery group was 7.5%, whereas none of the RFA-treated patients experienced any complications (P = .111).

CONCLUSION

This study revealed 6-year comparable outcomes between RFA and surgery for unilateral multifocal PTMC. RFA may be a safe and effective alternative to surgery in selected patients with unilateral multifocal PTMC.

Is Multifocality a Predictor of Poor Outcome in Childhood and Adolescent Papillary Thyroid Carcinoma?

CONTEXT

Total thyroidectomy in pediatric papillary thyroid carcinoma (PTC) is recommended in national guidelines because of the high incidence of multifocal disease (MFD).

OBJECTIVE

To determine the incidence of MFD in childhood and adolescent vs adult PTC and whether MFD is a predictor for poorer outcomes in childhood and adolescent PTC.

METHODS

We conducted an institutional review board-approved review of patients with PTC undergoing surgery (1986-2021) at Memorial Sloan Kettering Cancer Center. Clinical and pathological characteristics in patients with unifocal disease (UFD) and MFD were compared using Pearson's χ2 test. Survival outcomes were analyzed using the Kaplan-Meier method and log-rank test. Multivariate analysis assessed the impact of MFD on outcome.

RESULTS

MFD was less common in childhood and adolescent patients with PTC (45%; 127/283) than in adults (54%; 3023/5564; P = .002). Childhood and adolescent patients with UFD and MFD had similar tumor stage and PTC subtype at presentation, with no significant difference in histopathologic features. Median follow-up was 68 months. There was no significant difference in 5-year recurrence-free probability and overall survival was 100% in both groups. There was no significant difference in 5-year contralateral lobe PTC-free probability between patients with UFD and MFD treated with lobectomy. Multivariate analysis showed MFD was not a predictor for recurrence.

CONCLUSION

MFD was less common in childhood and adolescent patients with PTC than adults and was not a predictor of poor outcome on multivariate analysis, with excellent long-term outcomes in all patients with PTC. MFD does not appear to warrant completion thyroidectomy in childhood and adolescent patients selected for lobectomy.

Bilaterality as a Risk Factor for Recurrence in Papillary Thyroid Carcinoma

Previous studies suggested that the multifocality of papillary thyroid carcinoma (PTC) would increase the risk of recurrence; however, the impact of its bilaterality remains unclear. Between 2011 and 2018, 1258 patients with PTC underwent total thyroidectomy at Ewha University Medical Center. The 5-year recurrence-free survival rate was 95.7% in patients with bilateral PTC, while those with unilateral multifocal PTC and a unifocal tumor showed a 5-year event-free survival rate of 97.0% and 97.8%, respectively (p = 0.004). A multivariable Cox proportional hazards model indicated that bilaterality (HR 2.550, 95% CI 1.354-4.800), male sex (HR 2.010, 95% CI 1.007-4.013), and tumor size (HR 1.748, 95% CI 1.316-2.323) were associated with recurrence, although unilateral multifocality did not increase the risk of recurrence (HR 1.211, 95% CI 0.348-4.213). In conclusion, bilaterality was associated with aggressive features, including tumor size and microscopic ETE. Moreover, bilaterality was an independent predictor of recurrence in patients with PTC. Patients with bilateral PTC might require careful treatment and follow-up approaches.

Radiomics features from whole thyroid gland tissue for prediction of cervical lymph node metastasis in the patients with papillary thyroid carcinoma

OBJECTIVE

We aimed to develop a clinical-radiomics nomogram that could predict the cervical lymph node metastasis (CLNM) of patients with papillary thyroid carcinoma (PTC) using clinical characteristics as well as radiomics features of dual energy computed tomography (DECT).

METHOD

Patients from our hospital with suspected PTC who underwent DECT for preoperative assessment between January 2021 and February 2022 were retrospectively recruited. Clinical characteristics were obtained from the medical record system. Clinical characteristics and rad-scores were examined by univariate and multivariate logistic regression. All features were incorporated into the LASSO regression model, with penalty parameter tuning performed using tenfold cross-validation, to screen risk factors for CLNM. An easily accessible radiomics nomogram was constructed. Receiver Operating Characteristic (ROC) curve together with Area Under the Curve (AUC) analysis was conducted to evaluate the discrimination performance of the model. Calibration curves were employed to assess the calibration performance of the clinical-radiomics nomogram, followed by goodness-of-fit testing. Decision curve analysis (DCA) was performed to determine the clinical utility of the established models by estimating net benefits at varying threshold probabilities for training and testing groups.

RESULTS

A total of 461 patients were retrospectively recruited. The rates of CLNM were 49.3% (70 /142) in the training cohort and 53.3% (32/60) in the testing cohort. Out of the 960 extracted radiomics features, 192 were significantly different in positive and negative groups (p < 0.05). On the basis of the training cohort, 12 stable features with nonzero coefficients were selected using LASSO regression. LASSO regression identified 7 risk factors for CLNM, including male gender, maximum tumor size > 10 mm, multifocality, CT-reported central CLN status, US-reported central CLN status, rad-score, and TGAb. A nomogram was developed using these factors to predict the risk of CLNM. The AUC values in each cohort were 0.850 and 0.797, respectively. The calibration curve together with the Hosmer-Lemeshow test for the nomogram indicated good agreement between predicted and pathological CLN statuses in the training and testing cohorts. Results of DCA proved that the nomogram offers a superior net benefit for predicting CLNM compared to the "treat all or none" strategy across the majority of risk thresholds.

CONCLUSION

A nomogram comprising the clinical characteristics as well as radiomics features of DECT and US was constructed for the prediction of CLNM for patients with PTC, which in determining whether lateral compartment neck dissection is warranted.

Prognostic impact of lymph node characteristics after therapeutic neck dissection for classic N1 papillary thyroid cancer

BACKGROUND

The impact of lymph node characteristics on mortality and recurrence remains controversial. This study evaluated the prognostic impact of lymph node characteristics in a large, homogenous cohort of patients with therapeutic neck dissection for clinically N1 classic papillary thyroid cancer (PTC).

METHODS

All consecutive adult patients with therapeutic central and lateral neck dissection for PTC at a French referral centre were prospectively enrolled from January 2000 until June 2021. The primary outcome was the impact of lymph node characteristics in predicting a disease event (persistence or recurrence), using univariable and multivariable logistic regression modelling.

RESULTS

A total of 462 patients were included. Lymph node capsular rupture was seen in 260 patients (56.3 per cent). Median maximum lymph node size was 15 (i.q.r. 9-23) mm. The median central, lateral, and total lymph node ratio (LNR) was 0.50 (i.q.r. 0.22-0.75), 0.15 (i.q.r. 0.07-0.29), and 0.26 (i.q.r. 0.14-0.41), respectively. After a median follow-up of 93 (i.q.r. 50-149) months, 182 (39.4 per cent) patients had a disease event. After multivariable analysis, the number of harvested lymph node >35 (OR 2.33 (95 per cent c.i. 1.10-4.95)), presence of lymph node capsular rupture (OR 1.92 (1.17-3.14)), and total LNR >0.20 (OR 2.37 (1.08-5.19)) and >0.40 (OR 4.92 (1.61-15.03)) predicted a disease event. An LNR of 0.20 predicted a disease event with a sensitivity of 80.8 per cent and a specificity of 50.4 per cent.

CONCLUSION

Disease persistence or recurrence after thyroidectomy with therapeutic neck dissection for classic PTC with preoperative nodal disease appears to depend on number of harvested lymph node, presence of lymph node capsular rupture, and total LNR.

Effect of Waiting Time for Radioactive Iodine Therapy on Outcome in N1 Stage Papillary Thyroid Cancer

CONTEXT

The waiting time for radioactive iodine therapy (WRAIT) after total thyroidectomy (TT) in patients with papillary thyroid cancer (PTC) and lymph node metastases (N1) has not been sufficiently investigated for risk of adverse outcomes.

OBJECTIVE

This work aimed to estimate the effect of WRAIT on the outcomes of disease persistence and recurrence among patients with N1 PTC and investigate factors predictive of delayed radioactive iodine therapy (RAIT).

METHODS

This retrospective cohort study was conducted in a university hospital. A total of 909 patients with N1 PTC were referred for RAIT between 2014 and 2018. WRAIT is the duration between TT and initial RAIT. The optimal WRAIT threshold determined using recursive partitioning analysis was used to define early and delayed RAIT. The primary end point was tumor persistence/recurrence. We compared the outcomes of patients with early and delayed RAIT using inverse probability weighting based on the propensity score.

RESULTS

The WRAIT threshold that optimally differentiated worse long-term remission/excellent response outcomes was greater than 88 days (51% of our cohort; n = 464). WRAIT exceeding 88 days was associated with an augmented risk of disease persistence/recurrence (odds ratio, 2.47; 95% CI, 1.60-3.82) after adjustment. Predictors of delayed RAIT included residence in lower-income areas, reoperation before the initial RAIT, TT at a nonuniversity-affiliated hospital, multifocality, extrathyroidal extension, N1b disease, and pre-RAIT-stimulated thyroglobulin level less than 1 ng/mL.

CONCLUSION

Delayed RAIT beyond 88 days after TT in patients with N1 PTC independently increased the risk of disease persistence/recurrence. Evaluation of the predictive determinants of prolonged WRAIT may help target at-risk patients and facilitate interventions.

Cancer-associated fibroblasts in papillary thyroid carcinoma

Papillary thyroid carcinoma (PTC) has a relatively good prognosis, yet there are some invasive PTC cases with worse clinicopathological features and poor outcome. Cancer-associated fibroblasts (CAFs) play an important role in cancer invasion and metastasis. This study aimed to investigate the expression of marker proteins of CAFs in PTC and their correlations with clinicopathological features through immunohistochemistry. The medical records of 125 PTC patients were reviewed in this study, whose specimens were retrieved for immunohistochemistry. Four CAFs marker proteins, FAP fibroblast activated protein (FAP), α-smooth muscle actin (α-SMA), Vimentin and platelet-derived growth factor receptor-α(PDGFR-α), were stained and scored. Then, statistical analyses were performed. The immunoreactivity scores of FAP and α-SMA correlated with tumor size, BRAF mutation, extrathyroidal, invasion, pathological subtype, lymph node metastasis and ATA risk stratification. Moreover, binary logistic regression analysis and receiver operating characteristic curves showed that high FAP and α-SMA immunoreactivity scores were risk factors for extrathyroidal invasion, BRAF mutation, multi-focality and lymph node metastasis (especially N1b) with good sensitivity and accuracy in prediction. A better performance was found in FAP than α-SMA. Strong expressions of CAFs were risk factors for worse thyroid cancer clinicopathological features. FAP was the better CAFs marker for PTC.

Risk factors and predictive model for recurrence in papillary thyroid carcinoma: a single-center retrospective cohort study based on 955 cases

Background

The 2015 American Thyroid Association guidelines proposed recurrence risk stratification of differentiated thyroid carcinoma, including papillary thyroid carcinoma (PTC), but this stratification excluded non-initial treatment patients with worse outcomes. This study aimed to explore the potential risk factors for recurrence in PTC and develop a predictive model for both initial and non-initial treatment of patients with PTC.

Methods

A total of 955 patients were included in this study. Differences between the recurrence (-) and recurrence (+) groups were compared. The 955 patients were randomized into two groups: the training group (671 cases) and the validation group (284 cases). All variables were selected using the LASSO regression analysis. A nomogram was developed based on the results of the univariate and multivariate logistic regression analyses. The nomogram performance was evaluated using discrimination and calibration.

Results

Patients aged ≥55 years, extranodal extension (ENE), metastatic LN ratio (LNR) >0.5, and non-initial treatment were identified as potential risk factors for recurrence through LASSO regression and univariate and multivariate analyses. The receiver operating characteristic curve (ROC curve) showed high efficiency, with an area under the ROC curve (AUC) of 0.819 (95% confidence interval [CI], 0.729-0.909) and 0.818 (95% CI, 0.670-0.909) in the training and validation groups, respectively. The calibration curve indicated that the nomogram had a good consistency.

Conclusion

In patients with PTC, age ≥55 years, ENE, LNR >0.5, and non-initial treatment are potential risk factors for recurrence. The predictive model of recurrence was confirmed to be a practical and convenient tool for clinicians to accurately predict PTC recurrence.

The impact of multifocality on lateral lymph node metastasis in papillary thyroid carcinoma

PURPOSE

Multifocality is a common feature of papillary thyroid carcinoma (PTC) and is strongly associated with unfavorable outcome, but its association with lateral lymph node metastasis (lateral LNM) remains unclear.

METHODS

The association between tumor foci numbers and lateral LNM was assessed with unadjusted and adjusted logistic regression. Propensity score matching analysis was used to investigate the impact of tumor foci numbers on lateral LNM.

RESULTS

Increasing tumor foci numbers was strongly associated with a higher risk of lateral LNM (P < 0.05). After adjusting for several confounding factors, ≥4 tumor foci can be regarded as an independent predictor of lateral LNM (multivariable adjusted OR = 1.848, P = 0.011). Similarly, compared with solitary foci, multifocality was associated with a significantly higher risk of lateral LNM after matching propensity scores (11.9% vs. 14.4%, P = 0.018), especially for patients with ≥4 tumor foci (11.2% vs. 23.4%; P = 0.001). Furthermore, age-stratified analyses revealed multifocality was significantly positively correlated with lateral LNM in younger patients (P = 0.013) compared with older patient cohorts (P = 0.669).

CONCLUSIONS

Overall, tumor foci numbers significantly increased the risk of lateral LNM in PTCs, especially for patients with four or more tumor foci, and patient's age should be considered when interpreting the multifocality and risk of lateral LNM.

A Data-Driven Approach to Refine Predictions of Differentiated Thyroid Cancer Outcomes: A Prospective Multicenter Study

CONTEXT

The risk stratification of patients with differentiated thyroid cancer (DTC) is crucial in clinical decision making. The most widely accepted method to assess risk of recurrent/persistent disease is described in the 2015 American Thyroid Association (ATA) guidelines. However, recent research has focused on the inclusion of novel features or questioned the relevance of currently included features.

OBJECTIVE

To develop a comprehensive data-driven model to predict persistent/recurrent disease that can capture all available features and determine the weight of predictors.

METHODS

In a prospective cohort study, using the Italian Thyroid Cancer Observatory (ITCO) database (NCT04031339), we selected consecutive cases with DTC and at least early follow-up data (n = 4773; median follow-up 26 months; interquartile range, 12-46 months) at 40 Italian clinical centers. A decision tree was built to assign a risk index to each patient. The model allowed us to investigate the impact of different variables in risk prediction.

RESULTS

By ATA risk estimation, 2492 patients (52.2%) were classified as low, 1873 (39.2%) as intermediate, and 408 as high risk. The decision tree model outperformed the ATA risk stratification system: the sensitivity of high-risk classification for structural disease increased from 37% to 49%, and the negative predictive value for low-risk patients increased by 3%. Feature importance was estimated. Several variables not included in the ATA system significantly impacted the prediction of disease persistence/recurrence: age, body mass index, tumor size, sex, family history of thyroid cancer, surgical approach, presurgical cytology, and circumstances of the diagnosis.

CONCLUSION

Current risk stratification systems may be complemented by the inclusion of other variables in order to improve the prediction of treatment response. A complete dataset allows for more precise patient clustering.

Risk factors for recurrent disease in small papillary thyroid cancers - a Swedish register-based study

AIMS

To study the correlation between clinicopathological risk factors and the risk for intervention-requiring cancer recurrence in patients with small papillary thyroid cancers (sPTCs).

MATERIALS AND METHODS

Records for 397 patients with sPTC (T1 ≤ 20mm) were obtained from the Scandinavian Quality Register for Thyroid, Parathyroid and Adrenal Surgery (SQRTPA) between 2010 and 2016. Follow-up time was at least 5 years. Data regarding intervention-requiring cancer recurrence were obtained from patient medical records and analysed regarding lymph node (LN) status (N0, N1a and N1b) and recurrence.

RESULTS

Age was significantly lower in the N1a and N1b groups compared to N0 (45 vs. 40.5 vs. 49 years, respectively; p = 0.002). Tumour size was smaller in the N1a group compared to N1b group (9 vs. 11.8 mm; p <0.01). The mean number of metastatic LNs at initial surgery was higher in the N1b compared to N1a group (6.6 vs. 3; p = 0.001), and in the recurrent compared to the non-recurrent group (7 versus 3.9; p <0.01). The recurrence rate was higher in the N1b group than the N1a and N0 groups (25% vs. 2.4% vs. 1.4%, respectively; p = 0.001).

CONCLUSIONS

Lymph node stage N1b at diagnosis, and having five or more metastatic nodes, are strong risk factors for cancer recurrence and decreased disease-free survival in sPTC. The management of patients with sPTC should include thorough lymph node mapping for optimal treatment and individual risk stratification.

Vascularity depicted by contrast-enhanced ultrasound predicts recurrence of papillary thyroid cancer

PURPOSE

Although angiogenesis is crucial for the occurrence and development of solid tumors, the prognostic value of vascularity remains unclear in papillary thyroid cancer (PTC), due to the lack of effective techniques to evaluate vascularity. Contrast-enhanced ultrasound (CEUS) is an effective technique to evaluate vascularity. This study aimed to investigate whether vascularity depicted by CEUS was associated with structural recurrence in classic PTC.

METHODS

512 consecutive patients who underwent total thyroidectomy and central lymph node dissection for classic PTC larger than 1 cm between January 2015 and December 2018 and who were followed up for 12 months or longer were retrospectively enrolled. For this study, iso- and hyperenhancement were considered hypervascularity, whereas hypovascularity referred to hypoenhancement. Kaplan-Meier cumulative event curves for structural recurrence were compared using the log-rank test. The multivariate Cox proportional hazard regression analysis was used to estimate hazard ratios (HRs) of hypervascularity depicted by CEUS for structural recurrence.

RESULTS

61 (11.9 %) of 512 patients had structural recurrence. Hypervascular PTCs had a shorter recurrence-free survival rate than hypovascular PTCs (P < 0.001). In the multivariate analysis, hypervascularity (HR, 2.069; 95 % confidence interval [CI]: 1.087, 3.937), larger size (HR, 1.279; 95 % CI: 1.011, 1.618), multifocality (HR, 1.976; 95 % CI: 1.150, 3.396), extrathyroidal extension (HR, 2.276; 95 % CI: 1.026, 5.046), and lymph node metastasis (HR, 3.631; 95 % CI: 1.515, 8.701) were independently associated with structural recurrence.

CONCLUSION

Hypervascularity depicted by CEUS was independently associated with structural recurrence in patients with classic PTC.

Impact of completion thyroidectomy on postoperative recovery in patients with differentiated thyroid cancer

While an increasing number of patients now undergo lobectomy for low-risk differentiated thyroid cancer, a subset of patients require completion thyroidectomy to facilitate radioactive iodine therapy. Completion thyroidectomy is generally as safe as the initial operation, but a previous study showed that a longer hospitalization is required for completion thyroidectomy. In this study, we reviewed 61 consecutive patients who had been treated with an initial lobectomy and subsequent completion thyroidectomy at our institution from 2012 to 2021. We detected a changepoint in 2016 for the proportion of patients who were treated with a thyroid lobectomy (Pettitt's test P = 0.049). The rate of completion thyroidectomy remained stable throughout the study period. There was no difference in operating time, intraoperative blood loss, perioperative drop in calcium levels, and postoperative hospital stay between surgeries. The patients reported higher pain scores on the day of operation (P = 0.007) and the postoperative day 1 (P = 0.022). Occult papillary microcarcinomas were identified in the contralateral thyroid lobe in 13 (21%) patients. Multifocality was the only predictor for residual malignancy in multivariate regression. In conclusion, patients with differentiated thyroid cancer experienced more pain in the immediate postoperative period following completion thyroidectomy. Hospital stays do not change with appropriate opioid-free pain control.

Survival prognostic factors for differentiated thyroid cancer patients with pulmonary metastases: A systematic review and meta-analysis

Background

The prognostic factors for differentiated thyroid cancer (DTC) patients with pulmonary metastases (PM) remain scantly identified and analyzed. Therefore, this systematic review and meta-analysis were performed to identify and summarize the prognostic factors in adult DTC patients with PM to help distinguish patients with different prognoses and inform the rational treatment regimens.

Method

We performed a comprehensive search of the relevant studies published in the Cochrane Library, PubMed, Scopus, Embase, Wanfang database, VIP database, China National Knowledge Infrastructure, and Google Scholar from their inception until February 2021. The pooled hazard ratios (HR) for overall survival and/or progression-free survival (PFS) with 95% confidence intervals were applied to evaluate and identify the potential prognostic factors. Pooled OS at different time points were also calculated for the available data. A random-effects model was used in the meta-analysis.

Results

The review and meta-analysis included 21 studies comprising 2722 DTC patients with PM. The prognostic factors for poor OS were: age over 40 years (HR=7.21, 95% confidence interval [CI] 1.52-34.10, P=0.01, N=788), age over 45 years (HR=2.18, 95% CI 1.26-3.77, P<0.01, N=601), male gender (HR=1.01, 95% CI 1.01-1.19, P=0.03, N=1396), follicular subtype of thyroid cancer (HR=1.63, 95% CI 1.36-1.96, P<0.01, N=2110), iodine non-avidity (HR=3.10, 95% CI 1.79-5.37, P<0.01, N=646), and metastases to other organs (HR=3.18, 95% CI 2.43-4.16, P<0.01, N=1713). Factors associated with poor PFS included age over 45 years (HR=3.85, 95% CI 1.29-11.47, P<0.01, N=306), male gender (HR=1.36, 95% CI 1.06-1.75, P=0.02, N=546), iodine non-avidity (HR=2.93, 95% CI 2.18-3.95, P<0.01, N=395), pulmonary metastatic nodule size over 10mm (HR=2.56, 95% CI 2.02-3.24, P<0.01, N=513), and extra-thyroidal invasion (HR=2.05, 95% CI 1.15-3.67, P=0.02, N=271). The pooled 1, 3, 5, 10, 15, and 20-years OS were 95.24%, 88.46%, 78.36%, 64.86%, 56.57%, and 51.03%, respectively.

Conclusions

This review and meta-analysis identified the prognostic factors of DTC patients with PM. Notably, FTC, metastases to other organs, and iodine non-avidity were particularly associated with poor prognosis. The identified prognostic factors will help guide the clinical management of DTC patients with PM.

Systematic review registration

https://inplasy.com/inplasy-2022-2-0026/, identifier (INPLASY202220026).

A clinical study on microwave ablation of multifocal (≤ 3) T1N0M0 papillary thyroid carcinoma

OBJECTIVE

To evaluate the feasibility, efficiency, and safety of microwave ablation (MWA) for T1N0M0 multifocal (≤ 3) papillary thyroid carcinoma (PTC).

METHODS

This was a retrospective study, and patients who underwent MWA for multifocal (≤ 3) PTC were reviewed between October 2016 and December 2020. After ablation, the changes in tumor size and volume, as well as the rate of technical success, tumor disappearance, disease progression, and complications were assessed.

RESULTS

There were a total of 57 cases enrolled in the present study, which included 18 males and 39 females. The mean age was 44 ± 11 years (22-66 years); the mean follow-up time was 18 ± 11 months (6-48 months). Complete ablation was achieved in all enrolled cases. Therefore, the technical success rate was 100%. Due to expanding ablation, the MD and volume of the ablation zone, as well as the VRR, increased at the 1st and 3rd months after ablation and decreased at 12 and 18 months after ablation (p < 0.05 for all). The total complete tumor disappearance rate was 43.9% (25/57), including 54% (24/44) in the T1a subgroup vs. 7.7% (1/13) in the T1b subgroup (p = 0.003). The total disease progression rate was 7% (4/57), including 9.1% (4/44) in the T1a subgroup vs. 0% (0/13) in the T1b subgroup (p = 0.142). The overall complication rate was 5.3% (3/57), including 6.8% (4/44) in the T1a subgroup vs. 0% (0/13) in the T1b subgroup (p = 0.206).

CONCLUSION

This preliminary study indicates that MWA is a safe and effective treatment for T1N0M0 multifocal (≤ 3) PTC.

KEY POINTS

• MWA is a promising alternative method for T1N0M0 multifocal (≤ 3) PTC.

Pathological multifocality is not a prognosis factor of papillary thyroid carcinoma: a single-center, retrospective study

INTRODUCTION

Non-total thyroidectomy (non-TTx) is a widely accepted operative procedure for low-risk papillary thyroid carcinoma (PTC). PTC patients preoperatively diagnosed with unifocal disease are often revealed as having multifocal foci by microscopy. The present study determined whether or not patients with clinically unifocal, but pathologically multifocal non-high-risk PTC treated with non-TTx have an increased risk of a poor prognosis compared to those with pathologically unifocal PTC.

MATERIALS AND METHODS

PTC patients diagnosed as unifocal preoperatively who underwent non-TTx were multifocal in 61 and unifocal in 266 patients microscopically. Oncologic event rates were compared between pathologically multifocal and unifocal PTC patients.

RESULTS

Pathological multifocality was associated with positive clinical lymph node metastasis (cN1) (odds ratio [OR] 4.01, 95% confidence interval [CI]: 1.91-8.04) and positive pathological lymph node metastasis (pN1) in > 5 nodes (OR 3.68, 95% CI: 1.60-8.49). No patients died from PTC. There was no significant difference in the disease-free survival rate, remnant thyroid disease-free survival rate, lymph node disease-free survival rate, or distant disease-free survival rate between the two groups. Recurrence in pathologically multifocal PTC patients was locoregional in all cases and able to be salvaged by reoperation. Cox proportional hazard model analyses showed no significant difference in recurrence rates with regard to pathological multifocality and cN or number of pNs.

CONCLUSION

The prognosis of PTC with pathological multifocality treated by non-TTx was not inferior to that of unifocal PTC. Immediate completion thyroidectomy is not necessary when microscopic foci are proven.

Evolution of suppressing TSH therapy at diagnosis and in the long-term follow-up in a cohort of differentiated thyroid cancer

INTRODUCTION

To evaluate the adequacy of TSH suppression therapy (TSHst) at the first disease assessment and the last follow-up visit.

METHODS

Retrospective observational study of those patients under follow-up of DTC in a reference hospital.

RESULTS

216 patients (79.2% women) were evaluated, with a mean age 59.0 ± 13.1 years-old and a mean follow-up of 6.9 ± 4.3 years. 88.4% were papillary carcinomas. At diagnosis, 69.2% had a low risk of recurrence (RR) compared to 13.6% with a high RR. Dynamic risk stratification (DRS) classified patients at first disease assessment and the last visit as excellent response (ER) in 60.0% and 70.7%, respectively. Those patients with ER in the first and last follow-up control maintained TSHst in 30.7% and 16.3% of the cases, respectively (p < 0.001). The factors associated with maintaining TSHst at the last control were younger age, higher RR at diagnosis, DRE at follow-up, presence of multifocality and histological vascular invasion (p < 0.05). In a logistic regression analysis adopting tsTSH at follow-up as the dependent variable, exclusively age (β = -0.062; p < 0.001), RR at diagnosis (β = 1.074; p < 0.05) and EDR during follow-up (β = 1.237; p < 0.05) maintained statistical significance.

CONCLUSIONS

Despite the current recommendations, 30.7% of patients with low RR and initial ER are under TSHst. This percentage reduced to 16.3% in those patients with ER after a mean follow-up of 6.9 years. Age, baseline RR, and DRE during follow-up were associated to maintaining tsTSH.

Based on different immune responses under the glucose metabolizing type of papillary thyroid cancer and the response to anti-PD-1 therapy

Glucose metabolism-related genes play an important role in the development and immunotherapy of many tumours, but their role in thyroid cancer is ambiguous. To investigate the role of glucose metabolism-related genes in the development of papillary thyroid cancer (PTC) and their correlation with the clinical outcome of PTC, we collected transcriptomic data from 501 PTC patients in the Cancer Genome Atlas (TCGA). We performed nonnegative matrix decomposition clustering of 2752 glucose metabolism-related genes from transcriptome data and classified PTC patients into three subgroups (C1 for high activation of glucose metabolism, C2 for low activation of glucose metabolism and C3 for moderate activation of glucose metabolism) based on the activation of different glucose metabolism-related genes in 10 glucose metabolism-related pathways. We found a positive correlation between the activation level of glucose metabolism and the tumour mutation burden (TMB), neoantigen number, mRNA stemness index (mRNAsi), age, and tumour stage in PTC patients. Next, we constructed a prognostic prediction model for PTC using six glucose metabolism-related genes (PGBD5, TPO, IGFBPL1, TMEM171, SOD3, TDRD9) and constructed a nomogram based on the risk score and clinical parameters of PTC patients. Both the prognostic risk prediction model and nomogram had high stability and accuracy for predicting the progression-free interval (PFI) in PTC patients. Patients were then divided into high-risk and low-risk groups by risk score. The high-risk group was sensitive to paclitaxel and anti-PD-1 treatment, and the low-risk group was sensitive to sorafenib treatment. We found that the high-risk group was enriched in inflammatory response pathways and associated with high level of immune cell infiltration. To verify the accuracy of the prognostic prediction model, we knocked down PGBD5 in PTC cells and found that the proliferation ability of PTC cells was significantly reduced. This suggests that PGBD5 may be a relatively important oncogene in PTC. Our study constructed a prognostic prediction model and classification of PTC by glucose metabolism-related genes, which provides a new perspective on the role of glucose metabolism in the development and immune microenvironment of PTC and in guiding chemotherapy, targeted therapy and immune checkpoint blockade therapy of PTC.

The Predicting Role of Serum TSGF and sIL-2R for the Lymph Node Metastasis of Papillary Thyroid Carcinoma

Objective

To explore the clinical utility of tumor-specific growth factor (TSGF) and the soluble interleukin-2 (IL-2) receptor (sIL-2R) as immune-related factors for predicting lymph node metastases (LNM) of papillary thyroid carcinoma (PTC).

Methods

A total of 206 patients with PTC subjected to curative surgery were enrolled. All patients had complete medical records. Serum levels of TSGF were detected using Automatic Biochemistry Analyzer and the serum sIL-2R concentration was detected by enzyme-linked immunosorbent assay (ELISA). Furthermore, we analyzed the relationship between the two indicators and the clinicopathological characteristics and assessed their effect on lymphatic metastasis in patients with PTC by logistic regression analysis.

Results

Receiver operating characteristic (ROC) analysis revealed that the determined cut-off value of serum TSGF and sIL-2R was 63.35 U/mL and 507 U/mL, respectively. Serum TSGF was associated with focality (χ² = 4.97, P = 0.026) and lymphatic metastasis (χ² = 4.154, P = 0.042), while serum sIL-2R was remarkably related to gender (χ² = 4.464, P = 0.035). Univariate logistic regression analysis indicated that age, tumor size, serum TSGF level, capsule invasion, and nodular goiter were the lymphatic metastasis-related factor of PTC. Multivariate regression analysis revealed that age > 45 years was a protective factor (OR: 0.4, 95% CI: 0.206-0.777, P = 0.007). Conversely, larger tumor size (OR: 4.594, 95% CI: 2.127-9.921, P = 0.000), higher serum TSGF levels (OR: 1.888, 95% CI: 1.009-3.533, P = 0.047), and capsule invasion (OR: 1.939, 95% CI: 1.009-3.726, P = 0.047) were associated with an increased risk of LNM.

Conclusion

Serum TSGF levels were identified as an independent factor for LNM in patients with PTC.

Number of Tumor Foci as a Risk Factor for Recurrence in Papillary Thyroid Carcinoma: Does It Improve Predictability?

Multifocality in papillary thyroid carcinoma (PTC) increases the risk of recurrence. Some recent studies have suggested that multifocality-related parameters, such as the number of tumor foci, total tumor diameter (TTD), and bilaterality, are more useful for predicting recurrence than multifocality. However, it is still unclear if these factors can improve the accuracy of the recurrence prediction model. Between 2012 and 2019, 1288 patients with PTC underwent total thyroidectomy at Ewha Womans University Medical Center. The 5-year disease-free survival rate was 91.2% in patients with >3 tumor foci, 95.1% with 3 foci, and 97.6% with 2 foci; conversely, those with a unifocal tumor showed a 5-year recurrence-free survival rate of 98.0%. Cox proportional hazards analysis indicated that the number of tumor foci (HR for >3 foci, 3.214; HR for 3 foci, 2.473), bilaterality (HR, 2.530), or TTD (HR for >3 cm, 5.359; HR for 2−3 cm, 3.584) could be an independent predictor of recurrence. However, models using the number of tumor foci, bilaterality, and TTD did not show better overall predictability of recurrence than models based on multifocality. In conclusion, a simpler prediction model based on multifocality may be sufficient.

Clinical outcomes of multifocal papillary thyroid cancer: A systematic review and meta‐analysis

Objective

Methods

Results

Level of Evidence

Conclusion

Predictors of Recurrence in Patients with Papillary Thyroid Carcinoma: Does Male Sex Matter?

Male patients with papillary thyroid carcinoma (PTC) usually have aggressive clinicopathological features, including large tumor size and lymph node metastasis; however, it is unclear whether male sex increases the risk of recurrence. Here, we evaluated the effect of sex on disease-free survival (DFS) of patients with PTC. Between 2009 and 2016, 1252 patients who underwent total thyroidectomy for PTC were enrolled; 157 (12.5%) were male and 1095 (87.5%) were female. With a mean follow-up of 6.6 years, five-year DFS rates were comparable between male and female patients (94.9% vs. 96.9%; p = 0.616) after adjusting for potential confounders. Multivariate Cox regression analysis also demonstrated that male sex was not an independent risk factor for recurrence (HR 1.982, 95% CI 0.831−4.726). Subgroup analyses further indicated that both male and female sex—in terms of their associations with five-year DFS—were comparable with other variables, including age < 55 years (94.5% vs. 97.3%; p = 0.520) and tumor size > 1 cm (91.9% vs. 97.0%; p = 0.243). In conclusion, male sex was not associated with the risk of recurrence in patients with PTC. Male patients do not always require aggressive treatment and follow-up approaches.

Optimal Surgical Extent in Patients with Unilateral Multifocal Papillary Thyroid Carcinoma

Multifocality increases the risk of recurrence in patients with papillary thyroid carcinoma (PTC); however, it is unclear whether multifocality justifies more extensive or aggressive surgical treatment. Here, we evaluated the effect of the operative extent on the recurrence-free survival (RFS) of patients with multifocal PTC. Between 2010 and 2019, 718 patients with unilateral multifocal PTC were enrolled; 115 patients (16.0%) underwent ipsilateral thyroid lobectomy, and 606 patients (84.0%) underwent total thyroidectomy. With a mean follow up of 5.2 years, RFS was comparable between the total thyroidectomy and lobectomy groups (p = 0.647) after adjusting for potential confounders. Multivariable Cox regression analysis also demonstrated that the operative extent was not an independent predictor of recurrence (HR 1.686, 95% CI: 0.321-8.852). Subgroup analyses further indicated that both total thyroidectomy and thyroid lobectomy resulted in comparable RFS for multifocal PTC patients with other high-risk factors, including tumor size > 1 cm (p = 0.711), lymph node metastasis (p = 0.536), and intermediate ATA risk of recurrence (p = 0.682). In conclusion, thyroid lobectomy was not associated with the risk of recurrence in patients with multifocal PTCs. Multifocality in PTC may not always require aggressive surgery.

Nomogram model based on preoperative serum thyroglobulin and clinical characteristics of papillary thyroid carcinoma to predict cervical lymph node metastasis

OBJECTIVE

Preoperative evaluation of cervical lymph node metastasis (LNM) in papillary thyroid carcinoma (PTC) has been one of the serious clinical challenges. The present study aims at understanding the relationship between preoperative serum thyroglobulin (PS-Tg) and LNM and intends to establish nomogram models to predict cervical LNM.

METHODS

The data of 1,324 PTC patients were retrospectively collected and randomly divided into training cohort (n = 993) and validation cohort (n = 331). Univariate and multivariate logistic regression analyses were performed to determine the risk factors of central lymph node metastasis (CLNM) and lateral lymph node metastasis (LLNM). The nomogram models were constructed and further evaluated by 1,000 resampling bootstrap analyses. The receiver operating characteristic curve (ROC curve), calibration curve, and decision curve analysis (DCA) of the nomogram models were carried out for the training, validation, and external validation cohorts.

RESULTS

Analyses revealed that age, male, maximum tumor size >1 cm, PS-Tg ≥31.650 ng/ml, extrathyroidal extension (ETE), and multifocality were the significant risk factors for CLNM in PTC patients. Similarly, such factors as maximum tumor size >1 cm, PS-Tg ≥30.175 ng/ml, CLNM positive, ETE, and multifocality were significantly related to LLNM. Two nomogram models predicting the risk of CLNM and LLNM were established with a favorable C-index of 0.801 and 0.911, respectively. Both nomogram models demonstrated good calibration and clinical benefits in the training and validation cohorts.

CONCLUSION

PS-Tg level is an independent risk factor for both CLNM and LLNM. The nomogram based on PS-Tg and other clinical characteristics are effective for predicting cervical LNM in PTC patients.

Preoperative Ultrasonography in the Evaluation of Suspected Familial Non-Medullary Thyroid Cancer: Are We Able to Predict Multifocality and Extrathyroidal Extension?

Family history of thyroid cancer increases the risk of harboring thyroid malignancies that end up having extrathyroidal extension (ETE) and multifocality on histology; some authors suggest a more aggressive surgical approach. Their pre-operative identification could allow more conservative surgical procedures if none of these features are suspected. Our aim was to assess if neck ultrasonography could identify or exclude multifocality or ETE in these patients to tailor the extent of surgery. This retrospective study included patients with previous thyroid surgery, ≥1 first-grade relative with thyroid cancer, and who had undergone pre-surgical ultrasound. ETE was suspected in the case of thyroid border interruption or gross invasion of perithyroidal tissues. Multiple suspicious nodules were defined as suspicion of multifocal cancer. The cohort consisted of 45 patients (median age 49 years, 40 with thyroid cancer, 30 females). The positive predictive value of ultrasonography in predicting multifocality and ETE was 57.14% (25.25–84.03) and 41.67% (21.5–65.1%), respectively, while the negative predictive values were 63.2% (56.4–69.4%) and 72.7% (63.3–80.5%). Pre-operative ultrasound examination is unable to reliably identify or exclude multifocal disease or extrathyroidal extension. In patients scheduled for surgery and with a first-degree relative affected by DTC, a “negative” pre-operative US report does not exclude the potential finding of multifocality and ETE at final histopathology.