Impact of gross extrathyroidal extension into major neck structures on the prognosis of papillary thyroid carcinoma according to the American Joint Committee on Cancer eighth edition

Multiparameter and Ultrasound Radiomics Nomogram to Predict the Aggressiveness of Papillary Thyroid Carcinomas: A Multicenter, Retrospective Study

RATIONALE AND OBJECTIVES

To construct a multiparameter radiomics nomogram based on ultrasound (US) to predict the aggressiveness of thyroid papillary carcinoma (PTC).

MATERIALS AND METHODS

In total, 471 consecutive patients from three institutions were included in this study. Among them, patients from institution 1 were used for training (n = 294) and internal validation (n = 92), while 85 patients from institution 2 and institution 3 were used for external validation. Radiomics features were extracted from the conventional US. The least absolute shrinkage was employed to select the most relevant features for the aggressiveness of PTC, along with the maximum relevance minimum redundancy algorithm and selection operator. These features were then used to construct the radiomics signature (RS). Subsequently, relevant multiparameter ultrasound (MPUS) features from shear-wave elastic (SWE) and strain elastography (SE) will be extracted using multivariable logistic regression. The final radionics nomogram was conducted using the RS, clinical information, and conventional US and MPUS features. The receiver operating characteristic (ROC), calibration, and decision curves were used to evaluate the performance of the nomogram.

RESULTS

Multivariable logistic regression analysis indicated that age, nodule size, capsule abutment, SWV tumor, and RS were independent predictors of the aggressiveness of PTC. The radiomics nomogram, utilizing these characteristics, displayed impressive performance with an AUC of 0.920 [95% CI, 0.889-0.950], 0.901 [95% CI, 0.839-0.963], and 0.896 [95% CI, 0.823-0.969] in the training, internal, and external validation cohort. It outperformed the clinical US, MPUS, and RS models (p < 0.05). The decision curve analysis indicated that the nomogram offered valuable clinical utility.

CONCLUSION

The nomogram incorporated MPUS and radiomics have good diagnostic performance in predicting the aggressiveness of PTC which may help in the selection of the surgical modality.

Establishment and verification of the first prognostic nomograms in locally advanced thyroid cancer based on the analysis of clinical and follow-up information on 2396 patients

Background and objectives

The purpose of this research was to develop and validate the first prognostic nomograms for 3-, 5-, and 10-year cancer-specific survival (CSS) and overall survival (OS) in patients diagnosed with locally advanced thyroid cancer (LATC) by evaluating independent predictors of prognosis in a population of LATC patients.

Methods

Demographics, clinicopathologic characteristics, treatment, and follow-up of 2396 LATC patients in the surveillance, epidemiology, and end results database from 2004 to 2015 were retrospectively analyzed and compared with patients with LATC according to staging. We randomized all LATC patients into training and validation groups in a 7:3 ratio. Cox regression analyses helped us to derive independent prognostic factors for LATC patients. According to these results, we established and validated the first prognostic nomograms and risk stratification.

Results

In our research, the clinical information of LATC patients was compared and significant differences were found in the relevant variables including CSS and OS (P < 0.05), with CSS of 82.0 % and 49.0 %, and OS of 70.6 % and 40.0 %, respectively. Cox regression analyses showed that age at diagnosis, tumor diameter, presence of DM, extrathyroidal extension sites, histological type, thyroidectomy scope, radiotherapy status, and chronological sequence of radiotherapy and surgery were observably correlated with CSS in LATC patients, and in addition to the above factors, gender, marital status, and chemotherapy status were also observably correlated with OS in LATC patients. The prognostic predictive power of the above factors is visualized by the Kaplan-Meier survival curve. The concordance index of nomograms for CSS and OS were 0.933, 0.925, and 0.926 (CSS), 0.918, 0.909, and 0.906 (OS), respectively, and the time-dependent receiver operating characteristic curve, area under curve, calibration curve and decision curve analysis curve indicate that the nomograms have good discriminatory ability, accuracy and clinical applicability in both the training and validation groups.

Conclusions

In these findings, we drawed a conclusion that there were significant differences in clinical information between patients with T4a and T4b LATC, and we established and validated the first prognostic nomograms and risk stratification of CSS and OS for LATC patients at 3, 5, and 10 years, which will help clinicians to individualize their postoperative treatment and individualized follow-up.

Causal inference between aggressive extrathyroidal extension and survival in papillary thyroid cancer: a propensity score matching and weighting analysis

Background

Extrathyroidal extension is a major risk factor for poor prognosis in papillary thyroid cancer. However, the effect of different degrees of extrathyroidal extension on prognosis remains controversial. We performed a retrospective study to elucidate how the extent of extrathyroidal extension in papillary thyroid cancer affected the clinical prognosis of patients and its covariates.

Methods

The study included 108,426 patients with papillary thyroid cancer. We categorized the extent of extension into none, capsule, strap muscles, and other organs. Three causal inference methods for retrospective studies, namely, inverse probability of treatment weighting, standardized mortality ratio weighting, and propensity score matching analysis, were used to minimize potential selection bias. Kaplan-Meier analysis and univariate Cox regression analyses were applied to analyze the precise effect of ETE on survival in papillary thyroid cancer patients.

Results

In the Kaplan-Meier survival analysis, only extrathyroidal extension into or beyond the strap muscles was statistically significant for both overall survival (OS) and thyroid cancer-specific survival (TCSS). In univariate Cox regression analyses before and after matching or weighting based on causal inference, extrathyroidal extension into soft tissues or other organs is a high-risk factor for both overall survival and thyroid cancer-specific survival. Sensitivity analysis revealed that lower overall survival was observed in patients with older age (≥55) and larger tumor size (>2 cm) of papillary thyroid cancer with extrathyroidal extension into or beyond the strap muscles.

Conclusions

Our study indicates that extrathyroidal extension into soft tissues or other organs is a high-risk factor in all papillary thyroid cancer. Even though invasion into the strap muscles did not seem to be a marker for poor prognosis, it still impaired the overall survival of patients with older age (≥55 years old) or larger tumor size (>2 cm). Further investigation is needed to confirm our results and to clarify further risk factors independent of extrathyroidal extension.

The influence of nodule size on the aggressiveness of thyroid carcinoma varies with patient's age

Background

Thyroid nodule size is one of the key parameters that determines the operative approach for thyroid carcinoma. It is necessary to evaluate the influence of nodule size on the aggressiveness of thyroid carcinoma. The eighth edition of staging system has updated the prognostic age cutoff from 45 to 55 years old. It is needed to re-evaluate the difference in aggressiveness of thyroid carcinoma between younger (<55 years old) and older (≥55 years old) patients. Importantly, whether the influence of nodule size on the aggressiveness of thyroid carcinoma varies according to the new age stratification remains to be explored.

Methods

Medical records from patients were retrospectively reviewed. Patients with a documented thyroid ultrasonography (US), US-guided fine needle aspiration (FNA) and histopathology were included. The risks of unfavorable events such as central-compartment neck lymph node (CLN) metastasis, lateral-compartment neck lymph node (LLN) metastasis and gross extrathyroidal extension (ETE) were analyzed in four subsets of patients according to size and age.

Results

Large nodule size (≥10 mm) significantly increased the frequencies of CLN metastasis, LLN metastasis and gross ETE (P<0.05). The frequency of CLN metastasis was significantly higher in younger patients compared with that in older ones. Logistic regression analysis recognized large nodule size as an independent risk factor for all CLN metastasis (OR: 3.304, 95% CI: 2.473-4.415), LLN metastasis (OR: 9.673, 95% CI: 4.542-20.597), and gross ETE (OR: 2.430, 95% CI: 1.508-3.916). Secondly, in younger patients, frequencies of all CLN metastasis, LLN metastasis and gross ETE were significantly higher in nodules ≥10 mm than in nodules <10 mm (P<0.001). However, in older patients, no significant difference was found in the frequencies of LLN metastasis or gross ETE between nodules <10 mm and ≥10 mm. Logistic regression analysis showed, in younger patients, large nodule size was an independent risk factor for all CLN metastasis (OR: 3.241, 95% CI: 2.393-4.389), LLN metastasis (OR: 12.495, 95% CI: 5.281-29.562), and gross ETE (OR: 2.591, 95% CI: 1.519-4.419), while in older patients large nodule size was recognized as an independent risk factor for CLN metastasis (OR: 3.924, 95% CI: 1.413-10.899) but not for LLN metastasis or gross ETE.

Conclusions

Large nodule size is significantly related to high aggressiveness of thyroid carcinoma. The correlation between large nodule size and high aggressiveness varies according to patient's age, indicating that the presence of unfavorable events has different clinical significance for patients of varied ages. These findings contribute to accurately assessing the prognosis of individual patient and developing a better management strategy.