Corrigendum: Nomogram for predicting central lymph node metastasis in T1-T2 papillary thyroid cancer with no lateral lymph node metastasis.

[This corrects the article DOI: 10.3389/fendo.2023.1112506.].

Nomogram for predicting central lymph node metastasis in T1-T2 papillary thyroid cancer with no lateral lymph node metastasis.

Objective: Whether routine central lymph node dissection (CLND) is necessary for T1-T2 papillary thyroid carcinoma (PTC) patients without certain lateral lymph node metastases (LLNM) remains controversial. This study aims to construct a nomogram that predicts central lymph node metastasis (CLNM) for T1-T2 PTC patients without LLNM. Methods: We retrospectively reviewed adult T1-T2 PTC patients with no LLNM retrieved from the Surveillance, Epidemiology, and End Results (SEER) database from 2010 to 2015. We also collected data from patients treated at the First Hospital of China Medical University between February and April 2021 for external validation. Logistic regression model was used to construct a risk prediction model nomogram. The receiver-operating characteristic (ROC) curve, calibration plot, and decision curve analyses (DCA) were used for assessing the nomogram. Results: 5,094 patients from the SEER database and 300 patients from our department were finally included in this study. Variables such as age, gender, race, tumor size, multifocality, and minimal extrathyroidal extension (mETE) were found to be associated with CLNM and were subsequently incorporated into our nomogram. The C-index of our constructed model was 0.704, while the internal and external validation C-indexes were 0.693 and 0.745, respectively. The nomogram was then evaluated using calibration and decision curve analyses. Conclusion: A visualized nomogram was successfully developed to predict CLNM in T1-T2 PTC patients without LLNM and assist clinicians in making personalized clinical decisions.

Incidental T1 stage medullary thyroid carcinoma: The effect of tumour diameter on prognosis and therapeutic implications.

OBJECTIVE: The definition of the tumour diameter of micro-medullary thyroid carcinoma (micro-MTC) is insufficient. It is controversial to perform a completion thyroidectomy immediately for incidental T1 stage MTC. DESIGN: We used the Surveillance, Epidemiology and End Results (SEER) registry to retrospectively analyze all patients with T1 stage MTC diagnosed between 2004 and 2015. The tumour diameter 1.0 and 0.5 cm were used as the cut-off points to group and analyze the differences of clinicopathological features. We analyzed the prognosis of patients with less than total thyroidectomy. METHODS: The disease-specific survival was the main outcome. Survival was estimated with Kaplan-Meier curves and Cox regression models estimated hazard ratios for tumour characteristics. RESULTS: A total of 908 patients diagnosed with T1 stage MTC in the SEER database were included. Our study found that tumour diameter 1.0 cm is a key point affecting the prognosis of T1 stage MTC patients, although patients with tumour diameter ≤ 0.5 cm had a lower rate of lymph node metastasis and no distant metastasis. Cox proportional hazard multivariate analysis showed that distant metastasis was the only risk factor for survival in patients with T1 stage MTC. Kaplan-Meier survival analysis showed that, regardless of tumour diameter, there was no significant difference between less than total thyroidectomy and total thyroidectomy in T1 stage patients. CONCLUSIONS: For incidental MTC with tumour diameter ≤ 1.0 cm and without distant metastasis, if there is no significant increase in serum calcitonin level after surgery and ret proto-oncogene (RET) gene mutation is negative, it may be not necessary to perform completion thyroidectomy immediately.

High Incidence of Distant Metastasis Is Associated With Histopathological Subtype of Pediatric Papillary Thyroid Cancer - a Retrospective Analysis Based on SEER.

Objective: Children with papillary thyroid cancer (PTC) have a higher invasive rate and distant metastasis rate, but the mortality rate is lower with unknown reasons. The majority of PTC cases comprise classical papillary thyroid carcinoma (CPTC) and follicular variant papillary thyroid carcinoma (FVPTC). This study aimed to determine the relationship between histopathological subtype and rate of distant metastasis and investigate factors influencing distant metastasis in pediatric PTC. Methods: A total of 102,981 PTC patients were recruited from SEER registry, 2004-2015. Proportion of distant metastasis between children (≤18 years) and adults with different histopathological subtypes was compared by propensity score matching. The cut-off age for distant metastasis in children was calculated by receiver operating characteristic (ROC) curve, and the risk factors for distant metastasis in pediatric patients were analyzed by logistic regression models. Results: Among the 1,484 children and 101,497 adults included in the study, the incidence of CPTC patients with distant metastasis in children was higher than that in adults (p<0.001). The ROC curve was calculated, which yielded a cut-off age for distant metastasis in CPTC children as 16 years old. In CPTC, the proportion of young children (2-16 years) with distant metastasis was higher than that of adolescents (17-18 years) and adults (>18 years) (both p<0.001). While there was no such trend in FVPTC. In young children (2-16 years), the incidence of CPTC with distant metastasis was higher than FVPTC (p=0.006). There was no difference between the proportion of CPTC and FVPTC with distant metastasis in adolescents (17-18 years) and adults. Logistic regression models revealed that extrathyroidal extension, lymph node metastasis and CPTC histopathological subtype were risk factors for distant metastasis in young children aged 2 -16 years. Conclusions: In CPTC, the incidence of distant metastasis in young children (2-16 years) was significantly higher than that in adolescents (17-18 years) and adults (>18 years). In patients with distant metastasis aged 2-16 years, the proportion of CPTC was higer than that of FVPTC. Extrathyroidal extension, lymph node metastasis, and CPTC histopathological subtype were risk factors for distant metastasis in young children aged 2-16 years.

A relook at the 8th edition of the AJCC TNM staging system of anaplastic thyroid carcinoma: A SEER-based study.

OBJECTIVE: In the 8th edition American Joint Committee on Cancer (AJCC) tumour-node-metastasis (TNM) staging system (TNM-8), changes have been made regarding anaplastic thyroid carcinoma (ATC) compared with the 7th edition (TNM-7). The major changes are that anaplastic ATC now has the same T stage definitions as differentiated thyroid cancer, and new staging of IVA and IVB is implemented. However, the clinical impact of the new edition for ATC remains unclear due to scarce and conflicting data. In this study, we compared the AJCC TNM-7 and TNM-8 in the same group of patients. DESIGN: In this retrospective study, we included patients who were diagnosed with ATC between 2004 and 2015; data were gathered from the Surveillance, Epidemiology and End Results (SEER) database. METHODS: Overall survival (OS) was evaluated according to T stage and TNM stage according to the 7th and 8th editions. Kaplan-Meier and log-rank testing was used to analyse OS. The effect of potential predictors was estimated using the Cox regression model. RESULTS: We included 669 patients in the study. The median age of the cohort was 70 years. During the follow-up, 600 (89.7%) patients died, 528 of whom died of thyroid cancer. The TNM-8 T staging more effectively predicted survival than the 7th edition (proportion of variation explained: 3.53% vs. 1.72%). However, the clinical stage was almost unchanged according to the TNM-8 (proportion of variation explained: 10.69% vs. 10.73%). CONCLUSIONS: The new T classification is an effective predictor of survival for patients with ATC. The results support the use of T definitions as per those of differentiated thyroid cancer. However, whether lymph node metastasis should be taken into account for defining ATC TNM staging should be reconsidered.

The new T3b category has clinical significance? SEER-based study.

OBJECTIVE: As per the eighth edition of the American Joint Committee on Cancer (AJCC) staging system for differentiated thyroid carcinoma (DTC), minimal extrathyroidal extension (mETE) has been removed. Instead, gross ETE (gETE) invading only strap muscles has been designated as a new T3b category. Our objective was to investigate the impact of the T3b category on survival in order to establish its prognostic value in DTC. DESIGN: In this retrospective study, we included patients who had undergone thyroidectomy between 2004 and 2012. Data from the Surveillance, Epidemiology and End Results (SEER) database were examined. METHODS: We used the Kaplan-Meier method and log-rank test to analyse overall survival (OS) and cancer-specific survival (CSS). The effect of potential predictors associated with survival were estimated using the Cox regression model. To minimize selection bias, propensity-score matching (PSM) was performed. RESULTS: A total of 63 315 patients were included in our study. During the average follow-up duration of nearly 78 months, significant differences were observed in cancer-specific survival among patients with no ETE, mETE, gETE invading only strap muscles (T3b) and gETE invading perithyroidal structures other than strap muscles (T4) (P < .05). In univariable and multivariate analysis, both mETE and T3b exhibited significant poorer CSS compared with no ETE. After adjusting for patient features with PSM, it was confirmed that T3b was associated with worse CSS compared with no ETE and mETE. CONCLUSIONS: Both mETE and gETE are independent factors for DTC, implying that the new T3b category is worthy of reference for medical workers. Furthermore, mETE was significantly associated with poorer outcome. Our conclusion may provide support for the modification of the TNM staging system in the future.

Comparison of Outcomes Following Thyroid Isthmusectomy, Unilateral Thyroid Lobectomy, and Total Thyroidectomy in Patients with Papillary Thyroid Microcarcinoma of the Thyroid Isthmus: A Retrospective Study at a Single Center.

BACKGROUND Papillary thyroid microcarcinoma (PTMC) measures less than 10 mm in diameter, is more common in the thyroid lobes, but rarely presents in the thyroid isthmus. This retrospective study aimed to compare patient outcomes following various types of surgery in patients with PTMC of the thyroid isthmus, at a single center in China. MATERIAL AND METHODS We analyzed the clinical data of patients with isthmus thyroid cancer treated at the First Hospital of China Medical University. Patients were divided into 2 groups according to the tumor diameter-PTMC of the thyroid isthmus and papillary thyroid carcinoma >10 mm. The clinicopathological features between the 2 groups were compared, and the effects of various surgical methods on the prognosis of patients were analyzed. RESULTS A total of 70 patients were included in this study: 29 with PTMC of the thyroid isthmus (41.4%) and 41 with papillary thyroid carcinoma >10 mm (58.6%). The rates of lymph node metastasis (10.3% vs. 34.1%) and extrathyroid extension (0% vs. 14.6%) in the PTMC of the thyroid isthmus were significantly lower than those in the papillary thyroid carcinoma >10 mm. The recurrence-free survival (RFS) rate was 97.1%. Survival analysis showed that there was no significant difference in RFS among patients with PTMC of the thyroid isthmus undergoing isthmusectomy, unilateral lobectomy, and total thyroidectomy. CONCLUSIONS These findings from a single center showed that for patients with PTMC of the thyroid isthmus, who had no comorbidities, there was no significant difference in outcome between the 3 types of thyroid surgery.

Unilateral Tnm T1 And T2 Papillary Thyroid Carcinoma With Lateral Cervical Lymph Node Metastasis: Total Thyroidectomy or Lobectomy?

OBJECTIVE: The aim of this study was to explore the effect of total thyroidectomy (TT) and lobectomy (LT) on the prognosis of unilateral papillary thyroid carcinoma (PTC) with lateral cervical lymph node metastasis. METHODS: Patients with PTC and lateral cervical lymph node metastasis who underwent lateral cervical lymph node dissection between January 2007 and December 2016 were retrospectively reviewed. To investigate the effect of surgical procedure on the prognosis of lymph node metastasis patients, other high-risk factors such as extrathyroidal invasion and large tumor size were excluded. All patients were in Tumor-Node-Metastasis (TNM) stage T1 and T2. Primary end point was recurrence-free survival (RFS). RESULTS: Among 264 PTC patients, 104 (39.4%) patients received TT and 160 (60.6%) patients received LT. With a median follow-up of 50 months (interquartile range, 34 to 74 months), 7 patients (2.65%) experienced recurrence. The 5-year RFS in the TT and LT groups was 96.1% and 97.7%, respectively, and was not significantly different (P = .765). Similar results were found when excluding patients who received radioiodine ablation, which were 97.7% and 97.4%, respectively (P = .752). Age ≥55 years (hazard ratio, 7.368; P = .018) and multifocality in the ispi-lateral lobe (hazard ratio, 10.059; P =.006) were identified as independent risk factors of recurrence. CONCLUSION: For unilateral TNM T1 and T2 PTC patients with lateral lymph node metastasis, there was no significant difference in the effect of TT and LT for RFS in the absence of other risk factors during the follow-up period. Patient age ≥55 years with multifocality in the unilateral lobe might be independent risk factors for prognosis.