Therapeutic Outcomes of Patients with Multifocal Papillary Thyroid Microcarcinomas and Larger Tumors

A model based on ultrasound and clinical factors to predict central lymph node metastasis in cN0 papillary thyroid microcarcinoma

Objective

The prevalence of thyroid malignancies has sharply elevated in the past few years, and a large number of newly diagnosed thyroid malignancies was papillary thyroid microcarcinomas (PTMC). The efficacy of prophylactic central lymph node dissection (PCLND) in patients with clinical lymph node-negative (cN0) PTMC is still debatable. In this study, we aimed to create a predictive model to assess the likelihood of central lymph node metastasis (CLNM) in cN0 PTMC.

Methods

Two hundred and fifty three patients diagnosed with cN0 PTMC who received surgery in the First People's Hospital of Kunshan from October 2018 to June 2023 were enrolled. Multivariate logistic regression was employed to evaluate the patient's clinical and ultrasonographic information to determine independent factors. Two prediction models were generated and their ability to evaluate the likelihood of CLNM in cN0 PTMC was determined and compared.

Results

Multivariate analysis based on clinical characteristics revealed that, CLNM was markedly linked to age, tumor size, and extrathyroidal infiltration in cN0 PTMC. Multivariate analysis utilizing clinical and ultrasound features demonstrated that age, tumor size, extrathyroidal infiltration, shape, microcalcification were independent risk factors for CLNM. The analysis of the receiver operating characteristic curve demonstrated that the predictive nomogram utilizing clinical and ultrasound features was more beneficial for predicting CLNM. And decision curve demonstrates the same. The model's calibration curve exhibited strong consistency.

Conclusions

Age, tumor size, extrathyroidal infiltration, shape, microcalcification are significant independent factors of CLNM in cN0 PTMC. A predictive model derived from these independent clinical and ultrasound factors has a good value, but further validation is still required.

Microwave Ablation versus Surgical Resection for US-detected Multifocal T1N0M0 Papillary Thyroid Carcinoma: A 10-Center Study

Background Microwave ablation (MWA) is currently under preliminary investigation for the treatment of multifocal papillary thyroid carcinoma (PTC) and has shown promising treatment efficacy. Compared with surgical resection (SR), MWA is minimally invasive and could preserve thyroid function. However, a comparative analysis between MWA and SR is warranted to draw definitive conclusions. Purpose To compare MWA and SR for preoperative US-detected T1N0M0 multifocal PTC in terms of overall and 1-, 3-, and 5-year progression-free survival rates and complication rates. Materials and Methods In this retrospective study, 775 patients with preoperative US-detected T1N0M0 multifocal PTC treated with MWA or SR across 10 centers between May 2015 and December 2021 were included. Propensity score matching (PSM) was performed for patients in the MWA and SR groups, followed by comparisons between the two groups. The primary outcomes were overall and 1-, 3-, and 5-year progression-free survival (PFS) rates and complication rates. Results After PSM, 229 patients (median age, 44 years [IQR 36.5-50.5 years]; 179 female) in the MWA group and 453 patients (median age, 45 years [IQR 37-53 years]; 367 female) in the SR group were observed for a median of 20 months (range, 12-74 months) and 26 months (range, 12-64 months), respectively. MWA resulted in less blood loss, shorter incision length, and shorter procedure and hospitalization durations (all P < .001). There was no evidence of differences in overall and 1-, 3-, or 5-year PFS rates (all P > .05) between MWA and SR (5-year rate, 77.2% vs 83.1%; P = .36) groups. Permanent hoarseness (2.2%, P = .05) and hypoparathyroidism (4.0%, P = .005) were encountered only in the SR group. Conclusion There was no evidence of a significant difference in PFS rates between MWA and SR for US-detected multifocal T1N0M0 PTC, and MWA resulted in fewer complications. Therefore, MWA is a feasible option for selected patients with multifocal T1N0M0 PTC. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Georgiades in this issue.

Is lobectomy sufficient for multifocal papillary thyroid microcarcinoma?

IMPORTANCE

Multifocal papillary thyroid microcarcinoma (PTMC) has been associated with a higher incidence of lymph node involvement, bilateral involvement, and extrathyroidal extension compared to unifocal papillary thyroid cancer (PTC).

OBJECTIVE

To describe the incidence and determinants of survival for patients with multifocal PTMC using the Surveillance, Epidemiology, and End Result (SEER) database.

DESIGN, SETTING, PARTICIPANTS

The SEER registry was utilized to calculate survival trends for patients with PTMC between 2010 and 2015. Patient data was then analyzed with respect to age, sex, race, multifocality, and types of surgery rendered.

MAIN OUTCOMES AND MEASURES

Overall Survival (OS) and Disease Specific Survival (DSS).

RESULTS

22,283 cases of papillary thyroid microcarcinoma (T1a N0 M0) were identified. The cohort was composed of 82.6 % females, and about 82 % of patients were of white race. The mean age at diagnosis was 51.9 years. Multifocal PTMC was present in 32.2 % of the tumors (n = 7186). 73.9 % of patients underwent total thyroidectomy and 23.0 % received lobectomy. OS at 2 and 5 years was 98 % and 95 %, respectively. Multivariate analysis revealed that age, sex, and multifocality were determinants of OS. Only age was a determinant of DSS. Kaplan-Meier survival analysis revealed that multifocal PTMC had similar mean OS between lobectomy and total thyroidectomy patients (69.59 months versus 69.82 months).

CONCLUSIONS AND RELEVANCE

PTMC has a good prognosis. Our analysis revealed that age was a determinant of OS and DSS; sex and multifocality were also prognosticators for OS. The type of surgery, whether lobectomy or total thyroidectomy, was not a determinant of survival in multifocal PTMC.

Histopathological Types of Papillary Thyroid Carcinoma: Clinicopathologic Study

BACKGROUND: Papillary thyroid carcinoma (PTC) is the most common type of thyroid carcinoma that represents a set of characteristic of nuclear features in which the diagnosis is depend. AIM: The study aimed to review different variants of PTC which has different malignant potential in correlation with many prognostic and clinical factors in Iraq. PATIENTS AND METHODS: Paraffin blocks of 227 cases of PTC were selected, subtyped, and grouped according to the malignant potential. The prognostic and clinical factors were studied. RESULTS: The mean age was (39.29 ± 12.17) years, with female predominance (86.3%), where (55.5%) of them below 40 years, conventional variant was most common (40.1%), followed by papillary microcarcinoma variant, 197 cases (86.8%) were classified as low to intermediate malignant potential, and 30 cases (13.2%) were classified as high malignant potential. On comparison, among the tumor stages, tumor focality, native capsular invasion, lymph nodes involvement, presence or absence of vascular invasion, extrathyroid extension, and distant metastasis, there is no significant correlation between them, whereas with the tumor size, there is significant correlation between them (p =< 0.05). CONCLUSION: Conventional type followed by micropapillary type is most common. The mean age in Iraqi patients is lower than other countries for PTC. There is no significant association regarding prognostic factors between low to intermediate malignant potential variants and high malignant potential variants with exception of tumor diameter.

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

Importance

Multifocality is common in papillary thyroid carcinoma (PTC), but it is unclear whether multifocal tumors are associated with tumor recurrence or cancer-specific survival.

Objective

To compare tumor recurrence rates in patients with multifocal vs unifocal PTCs.

Data Sources

We searched PubMed, SCOPUS, Web of Science Core Collection, and Cochrane Database of Systematic Reviews for pertinent studies published in English from inception to June 30, 2020.

Study Selection

The search strategy yielded 26 studies that compared tumor recurrence in patients with multifocal vs unifocal PTC.

Data Extraction and Synthesis

Data was extracted in accordance with the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-analyses guideline. Characteristics of study populations and hazard ratio (HR) of multifocality were independently extracted by 2 investigators.

Main Outcomes and Measures

The primary outcome was tumor recurrence and the secondary outcome was cancer-specific survival. Subgroup analysis of the primary outcome was based on primary tumor size, number of tumor foci, and patient age.

Results

Among 26 studies with a total of 33 976 patients, recurrence rates were significantly higher in patients with multifocal PTC than in those with unifocal PTC (pooled HR, 1.81; 95% CI, 1.52-2.14). Cancer-specific survival was comparable between the groups (HR, 1.19; 95% CI, 0.85-1.68). In subgroup analyses, the HRs of multifocality for recurrence were associated with primary tumor size (HRs for PTC ≤1 cm and >1 cm were 1.81 and 1.90, respectively), number of tumor foci (HRs for 2 foci and ≥3 foci were 1.45 and 1.95, respectively), and patient age (HRs for pediatric and adult patients were 3.19 and 1.89, respectively).

Conclusions and Relevance

This systematic review with meta-analysis found that multifocality was significantly associated with an increased risk of recurrence in patients with PTC, while cancer-specific survival showed no difference. Differences in tumor size, number of tumor foci, and patient age should be considered when interpreting the multifocality and the risk of recurrence.

Oncosuppressor-Mutated Cell-Based Diagnostic Platform for Liquid Biopsy Diagnoses Benign Head and Neck Masses and Predicts Malignancy in Thyroid Nodules: Results from a Consecutive Cohort of Patients

BACKGROUND

We reported that a novel oncosuppressor-mutated cell (OMC)-based platform has the potential for early cancer detection in healthy individuals and for identification of cancer patients at risk of developing metachronous metastases.

OBJECTIVE

Herein, we sought to determine the diagnostic accuracy of this novel OMC-based platform in a consecutive cohort of patients operated for suspicious head and neck masses.

METHODS

OMCs (BRCA1-deficient fibroblasts) were exposed to blood serum from patients with head and neck nodules before surgical removal. These cells were analyzed for their proliferation and survival. Treated OMCs were inoculated subcutaneously in NOD/SCID mice, and tumor growth was monitored over time.

RESULTS

OMCs exposed to serum from patients with malignant lesions displayed increased proliferation compared to those exposed to serum from patients with benign lesions. Only OMCs exposed to serum from patients diagnosed with malignant thyroid neoplasia generated a cancerous mass. The sensitivity of the test was 92%, with only 1 false negative out of 34 patients. Immunohistochemical staining showed that the cancerous masses were poorly differentiated adenocarcinomas with high proliferative index.

CONCLUSIONS

These data show that liquid biopsy combined with an OMC-based in vivo platform has the potential to diagnose benign head and neck masses and predict whether a thyroid nodule is malignant. These results strengthen the concept that OMCs can be used to detect circulating malignant factors in cancer patients.

Disease-free Survival of Patients with Differentiated Thyroid Cancer: A Study from a Tertiary Center in Oman

Objectives

As with global trends, the prevalence of differentiated thyroid cancer (DTC) has increased in recent years in Oman. However, to the best of our knowledge, no local studies have yet been published evaluating the prognosis of DTC cases in Oman. This study aimed to assess disease-free survival (DFS) and prognostic factors related to DTC among Omani patients attending a tertiary care center.

Methods

This retrospective, observational cohort study was conducted between January 2006 and May 2016 at the National Diabetes and Endocrine Center in Oman. Data related to DFS and prognostic factors were obtained from the electronic medical records of all ≥ 18-year-old patients diagnosed with DTC during the study period.

Results

A total of 346 DTC cases were identified. Overall, 82.7% of patients were disease-free at their last follow-up appointment. Univariate analysis indicated that various tumor characteristics including histological subtype (i.e., papillary carcinoma, Hurthle cell cancer, and minimally invasive follicular thyroid carcinoma), lymph node status, number of lymph node metastases, distant metastasis status, and TNM status (primary tumor (T), regional lymph node (N), distant metastasis (M) stage) were strong prognostic factors for DFS (p < 0.050). According to multivariate regression analysis, lymph node status, extrathyroidal extension, and angiovascular invasion were independent predictors of DFS (p < 0.050).

Conclusions

The overall prognosis of DTC among Omani patients was excellent. Treatment and follow-up strategies for patients with DTC should be tailored based on the individual’s risk factor profile.

Does Multifocal Papillary Thyroid Microcarcinoma With a Total Tumor Diameter >1 cm Indicate Poor Biological Behavior? The Evidence is Insufficient

OBJECTIVE

Multifocal cancer is common in papillary thyroid microcarcinoma (PTMC). Our aim was to investigate the correlation between multifocal PTMC, total tumor diameter (TTD), and clinicopathologic features.

METHODS

In total, 206 patients were included and grouped as stage cT1a or cT1b. The primary tumor diameter and TTD (the sum of the maximal diameter of each focus) were calculated. These patients were further subgrouped as TTD ≤1 cm or 1 cm < TTD ≤ 2 cm. The relationships of clinicopathological features between these groups were analyzed.

RESULTS

Multifocal cancer was more likely to occur with stage cT1a than stage cT1b (P = .028). Stage cT1b papillary thyroid carcinoma was more prone to central lymph node metastasis (CLNM) and capsular invasion than stage cT1a. There was no difference in clinicopathological factors, such as sex, age, CLNM, number of CLNMs, capsular invasion, BRAF mutation, or recurrence between the multifocal PTMC and TTD >1 cm and primary tumor diameter + TTD ≤1 cm groups. Comparing stage cT1a and cT1b tumors with a 1 cm < TTD ≤ 2 cm using a multivariate analysis, stage cT1b tumors were more prone to capsular invasion than stage cT1a tumors, with an odds ratio of 19.013 (95% confidence interval, 2.295-157.478), but there was no significant correlation with CLNM.

CONCLUSION

Stage cT1b tumors are more prone to capsular invasion and CLNM than than stage cT1a tumors. For multifocal PTMC, calculating the TTD to evaluate adverse biological behavior is insufficient and limited, and further research is needed.

Risk Factors for Contralateral Occult Carcinoma in Patients With Unilateral Papillary Thyroid Carcinoma: A Retrospective Study and Meta-Analysis

BACKGROUND

Bilateral lesions are common in papillary thyroid carcinoma (PTC). For patients with unilateral PTC, occult carcinoma that is not detected preoperatively, but pathologically after surgery, might remain in the contralateral lobe. In this situation, inadequate surgical extent could cause relapse and even lead to re-operation. Here, we explore the frequency and investigate the risk factors of contralateral occult PTC in unilateral PTC through a retrospective study conducted by our team and published articles online, respectively.

METHODS

We collected the patients' clinical data in our hospital, whose cancer was determined to be confined to the unilateral lobe by preoperative image examination (N = 204). These patients underwent initially total or near-total thyroidectomy and included their clinical data in the meta-analysis. We searched related literature in the PubMed, Embase, MEDLINE, Cochrane, and Web of Science databases until December 7, 2020, in order to perform a meta-analysis. The relevant articles were examined and the eligible studies were included to assess the association between clinicopathologic factors and contralateral occult PTC.

RESULTS

The meta-analysis included nine studies (involving 4347 patients). Of these, eight studies were from the databases, and one study was our retrospective data. The meta-analysis showed that the prevalence of contralateral occult PTC was 26.6% in all patients. A tumor size > 1 cm, ipsilateral multifocality, contralateral benign nodule, and central lymph node metastasis were significantly associated with contralateral occult PTC. In contrast, sex, age, ETE, capsular invasion, BRAF mutation, Hashimoto thyroiditis, and lateral lymph node metastasis were insignificantly associated with contralateral occult PTC.

CONCLUSION

The meta-analysis identified a tumor size > 1 cm, ipsilateral multifocality, contralateral benign nodule, and CLNM as being significant risk factors for contralateral occult PTC. These findings may guide the extent of surgery in unilateral PTC patients.

Influence of Tumor Number on Clinicopathologic Features and Outcomes of Patients With Papillary Thyroid Carcinoma

OBJECTIVES

The purpose of this study was to investigate the significance of tumor number on clinicopathologic factors and outcomes of patients with papillary thyroid carcinoma (PTC).

METHODS

We retrospectively analyzed 667 patients with PTC. We compared clinicopathologic features of patients with a different tumor number. Cox proportional hazards model was used to analyze risk factors of recurrence.

RESULTS

In papillary thyroid microcarcinoma (PTMC), the increase in the number of tumor foci was related to a higher risk of minimal extrathyroidal extension (ETE) and lymphovascular invasion (P < .05). Patients with PTMC with four or more foci had a significantly higher risk of central lymph node metastasis (CLNM) and lateral lymph node metastasis (LLNM) than patients with solitary tumors (P < .05). Patients with macro-PTC with four or more foci and with three foci had a higher risk of gross ETE and lymphovascular invasion than patients with solitary tumors (P < .05). The increase in the tumor number was related to a higher risk of CLNM in macro-PTC (P < .05). The number of foci was the independent predictor of recurrence in patients with macro-PTC (P < .05).

CONCLUSIONS

An increase in the number of tumors was associated with an increased risk of aggressive clinicopathologic features in PTMC and macro-PTC. The number of tumor foci could influence risk of recurrence in macro-PTC.

Clinical and pathologic predictors of lymph node metastasis in papillary thyroid microcarcinomas

Papillary thyroid microcarcinoma (PTMC) has the highest incidence among all thyroid carcinomas. Although surgery is the primary treatment for PTMC, it inevitably leads to trauma and some complications. To formulate an optimal treatment strategy, we aim to clarify the risk factors for lymph node metastasis (LNM) in PTMC patients. This study retrospectively analyzed patients who underwent thyroidectomy during 1995-2015, and grouped them according to lymph node metastasis. Age, gender, tumor size, thyroid functions, Hashimoto's thyroiditis, multifocal tumor, extrathyroidal extensions, capsular invasion were analyzed. Of the 2434 PTMC subjects, proportion of patients with no LNM (NLNM), LNM, central LNM (CLNM), lateral LNM (LLNM), CLNM + LLNM were 82.9%, 17.1%, 7.0%, 7.6% and 2.5%. Patients with NLNM were older and had a lower proportion of males compared to patients with CLNM, LLNM and CLNM + LLNM (p < 0.05). The NLNM group also had a smaller size of ultrasound tumor, lower proportion of multifocal tumor and extrathyroidal extension compared to CLNM, LLNM and CLNM + LLNM groups (p < 0.05). On univariate analyses, male gender, age <45 years, tumor size of pathology (˃0.75 cm), multifocality, and extrathyroidal extension were significantly associated with LNM. Multivariate analyses revealed that male gender, age <45 years, multifocality were risk factors for LNM. In conclusion, PTMC patients with male gender, age <45 years and multifocality should be evaluated carefully for possible LNM.

Clinical and ultrasonographic features of medullary thyroid microcarcinomas compared with papillary thyroid microcarcinomas: a retrospective analysis

Background

To identify the sonographic features that help to differentiate medullary thyroid microcarcinomas (MTMCs) from papillary thyroid microcarcinomas (PTMCs).

Methods

A total of 46 MTMCs in 41 patients and 136 PTMCs in 104 patients that were proven by surgery and pathology were included in the study. Patient age and nodule size were analyzed by independent sample t-tests, and sex, multiplicity and cervical lymph node metastases were analyzed by χ² or Fisher’s exact tests. Univariate analysis and multivariate logistic regression analysis were performed on the sonographic features of thyroid nodules, including location, shape, boundary, margin, peripheral halo ring, echogenicity, composition, calcifications and vascularization.

Results

Compared with the corresponding number of patients with PTMCs, more MTMC patients had cervical lymph node metastases (P = 0.040). There were no significant differences in age, sex, nodule size, multiplicity, location, boundary, margin, peripheral halo ring, echogenicity or microcalcifications between MTMCs and PTMCs (P > 0.05 for all). However, significant differences were found in shape (P = 0.000), composition (P = 0.032), macrocalcifications (P = 0.004) and vascularity (P = 0.000) between the two groups.

Conclusions

There were some overlapping sonographic features between MTMCs and PTMCs. However, MTMCs tended to have a > 50% solid composition, be ovoid to round nodules with macrocalcifications and be hypervascular. Cervical lymph node metastases were more common in MTMC patients.

Total tumor diameter: the neglected value in papillary thyroid microcarcinoma

BACKGROUND

Tumor multifocality is not uncommon in papillary thyroid carcinoma (PTC), especially in micro-PTC. However, assessing the size of the largest tumor may underestimate effect of additional foci. We aimed to investigate the effect of total tumor diameter (TTD) on clinicopathological features of micro-PTC.

METHODS

Data from 442 patients who underwent thyroidectomy with cervical lymph node dissection for PTC were retrospectively analyzed. Patients were classified into subgroups according to multifocality and TTD. The relationships of clinicopathological features among these groups were analyzed.

RESULTS

Multifocality was observed in 119 patients (26.9%). TTD > 1 cm and presence of extrathyroidal extension (ETE) were significantly higher in multifocal tumors compared to unifocal tumor (P < 0.001, P = 0.016, respectively). When comparing multifocal micro-PTC with TTD > 1 cm to those with unifocal micro-PTC or multifocal micro-PTC with TTD ≤ 1 cm, the proportions of cases with ETE, central lymph node metastasis (CLNM), and lateral lymph node metastasis (LLNM) were significantly higher (all P < 0.05). There was no significant difference in terms of these parameters between multifocal micro-PTC with TTD > 1 cm and macro-PTC or multifocal macro-PTC. The risk of CLNM was 2.056 (P = 0.044) times higher in multifocal micro-PTC with TTD > 1 cm than in unifocal micro-PTC.

CONCLUSION

For multifocal micro-PTC, TTD can better assess the aggressiveness of the tumor. Multifocal micro-PTC with TTD > 1 cm was more aggressive than unifocal micro-PTC or multifocal micro-PTC with TTD ≤ 1 cm.

Management of Clinically Solitary Papillary Thyroid Carcinoma Patients According to Risk-Scoring Model for Contralateral Occult Carcinoma

OBJECTIVE

The aim of this study was to investigate risk factors of occult carcinoma in clinically solitary papillary thyroid carcinoma (PTC) patients, and to put emphasis on the predictive value of risk-scoring model to determine the optimal scope of surgery.

METHODS

A total of 573 clinically solitary PTC patients who underwent total thyroidectomy (TT) from two hospitals were retrospectively analyzed. Clinicopathological features were collected, univariate and multivariate analyses were performed to determine risk factors of occult carcinoma. The Cox proportional hazards model was used to analyze the risk factors of recurrence. A scoring model was constructed according to independent risk factors of contralateral occult carcinoma.

RESULTS

19.2% of clinically solitary PTC patients had occult carcinoma, among which 3.7% patients had ipsilateral occult carcinoma and 15.5% patients had contralateral occult carcinoma. Factors such as male, the presence of benign nodule, and vascular invasion increase the risk of ipsilateral occult carcinoma. Tumor size >1 cm, the presence of benign nodule, extrathyroidal extension, central lymph node metastasis, lateral lymph node metastasis are independent predictors of contralateral occult carcinoma. Contralateral occult carcinoma is the independent predictor of recurrence. A 10-point risk-scoring model was established to predict the contralateral occult carcinoma in clinically solitary PTC patients.

CONCLUSION

Lobectomy is sufficient for clinically solitary PTC patients with risk factors of ipsilateral occult carcinoma. For clinically solitary PTC patients with score ≥4, careful preoperative evaluations are required to rule out the contralateral occult carcinoma. Even if contralateral occult carcinoma is not detected preoperatively, TT is recommended for high-risk patients.

The occurrence of and predictive factors for multifocality and bilaterality in patients with papillary thyroid microcarcinoma

Thyroidectomy or hemithyroidectomy may be performed as treatment for papillary thyroid microcarcinoma (PTMC). However, in cases of bilateral PTMCs, only thyroidectomies should be recommended. Sometimes bilateral PTMC may be undetected in presurgical evaluations, so reoperation might be necessary after a partial thyroid resection. The aim of this study was to assess the occurrence of and predictive factors for the multifocality and bilaterality of PTMCs.We performed a retrospective review of 4716 consecutive patients with thyroid tumors. Of these patients, 434 (9.2%) had thyroid malignancies. All patients underwent thyroidectomies with central and/or lateral lymph node dissection between January 2008 and December 2017. PTMC was identified in 177 (3.75%) individuals.Solitary PTMC was observed in 114 (64.4%) patients, multifocal PTMC was seen in 48 (27.1%) patients, and bilateral PTMC was detected in 15 (8.5%) patients. The occurrence of solitary PTMC increased from 11.1% in 2008 to 61.9% in 2017. The occurrence of multifocal tumors significantly decreased from 77.8% in 2008 to 6.3% to 18.4% in 2013 to 2016 (P < .05). The occurrence of bilateral tumors, with respect to all PTMC cases, did not change during the 10-year period. We observed significantly higher rates of hypoechogenicity, more microcalcifications, more irregular margins, larger tumor sizes, and higher vascularity in the patients with multifocal and bilateral tumors than in the patients with solitary tumors (P < .0001 for all).The occurrence of bilateral PTMC is not very common. In patients with PTMC, thyroidectomy should be considered when microcalcifications, an irregular tumor shape, unclear margins, hypoechogenicity, high vascularity, and a large tumor size are observed. These clinicopathological features are prognostic factors for multifocal and bilateral PTMC.