Differences in the clinical characteristics of papillary thyroid microcarcinoma located in the isthmus ≤5 mm and >5mm in diameter

[Surgical approach selection and prognosis analysis of papillary thyroid microcarcinoma in the isthmus]

Objective:To compare the prognosis of papillary thyroid microcarcinoma of the isthmus（PTMCI） after different surgical methods, and to investigate the most appropriate surgical plan for it, so as to provide reference for the selection of clinical surgical plan. Methods:The clinical data of 106 PTMCI patients diagnosed with postoperative pathology after surgical treatment in Department of Otolaryngology Head and Neck Surgery, Ningbo Medical Center Lihuili Hospital from January 2016 to June 2023 were retrospectively analyzed. The patients were divided into 3 groups according to whether there were nodules in the lateral lobe of the thyroid gland, namely, isolated PTMCI group, PTMCI group with unilateral lobe nodules, and PTMCI group with bilateral lobe nodules. Combined with follow-up information, the differences of recurrence rate, survival rate and postoperative complications after different surgical methods were compared among all groups. The surgical procedures included isthmic thyroidectomy, isthmic + unilateral lobectomy, and total thyroidectomy. All patients underwent central lymph node dissection at the same time. Results:There were no significant difference in recurrence rate, survival rate and postoperative complications among all groups and between groups. Postoperative recurrence occurred in 2 patients, among which 1 patient was PTMCI with multiple focal tumors in unilateral lobe undergoing isthmus + unilateral lobectomy + ipsilateral central lymph node dissection. The recurrence was manifested as contralateral cervical lymph node metastasis. Another case of PTMCI with bilateral benign nodules underwent isthmus + unilateral lobe（larger nodule） resection + ipsilateral central lymph node dissection, and the recurrence was manifested as residual glandular recurrence. One patient developed permanent hoarseness after surgery. The postoperative pathology of 31 patients（29.2%） indicated multiple focal thyroid carcinoma. Postoperative pathology of 41 patients（38.7%） suggested lymph node metastasis in the central region of neck. The disease-specific survival rate was 100%. Conclusion:Isthmic thyroidectomy is recommended for isolated PTMCI. Isthmus of thyroid+ unilateral lobectomy is feasible for PTMCI with unilateral lobectomy. If multiple suspicious malignant nodules（≥3） occur in unilateral lobectomy, total thyroidectomy is recommended. Total thyroidectomy is feasible for PTMCI with bilateral nodules. All PTMCI patients should undergo prophylactic central cervical lymph node dissection at the same time.

Prognostic factors for aggressiveness in subcentimeter papillary thyroid carcinoma: impact of tumor size and lymph node metastases

Objective

Subcentimeter papillary thyroid carcinoma (sPTC), also known as papillary thyroid microcarcinoma, is associated with a good prognosis and low mortality risk. However, some sPTCs exhibit biologically aggressive characteristics. The aim of this study was to identify factors affecting the prognosis and aggressiveness of sPTC by considering the demographic characteristics of patients with sPTC and the pathologic characteristics of the tumors.

Subjects and methods

The study included 255 patients aged ≥ 18 years who were operated on at Ondokuz Mayis University, Faculty of Medicine (Samsun, Turkey) between June 2008 and December 2021. All patients had histopathologic confirmation of sPTC (≤10 mm) and underwent regular follow-up for at least 36 months.

Results

The tumors had a mean size of 5 mm (0.1-10 mm) and were multifocal in 53.7% of patients. Capsular invasion was observed in 9% of patients. Vascular invasion, lymphatic invasion, and extrathyroidal invasion were present in 2%, 5.5%, and 0.8% of patients, respectively. Metastatic cervical lymph nodes were observed in 9.4% of patients. On multivariate logistic regression analysis, tumor size (odds ratio [OR] 1.380, 95% confidence interval [CI] 1.106-1.722, p = 0.004) and sex (OR 4.233, 95% CI 1.355-13.226, p = 0.013) were the main predictive factors influencing lymph node metastasis. Tumors > 5 mm, compared with tumors ≤ 5 mm, had higher rates of multifocality (p = 0.009), parenchymal invasion (p = 0.008), calcifications (p = 0.001), microscopic lymphatic invasion (p = 0.002), and presence of metastatic lymph nodes (p < 0.001).

Conclusion

The findings of this study highlight important factors to consider in making decisions about prophylactic central compartment neck dissection in patients with sPTCs, particularly those with clinically node-negative tumors.

Clinical value of ultrasound parameters PI, TTP, and MTT in assessing cervical lymph node metastasis of papillary thyroid carcinoma

OBJECTIVE

To determine the clinical value of ultrasound in assessing cervical lymph node metastasis (CLNM) in papillary thyroid carcinoma (PTC).

METHODS

The medical records of 179 PTC patients treated in Shandong Provincial Qianfoshan Hospital between March 2016 and March 2019 were collected. The patients were assigned to a transfer group (54 cases) and a non-transfer group (125 cases) according to their pathologic results. The ultrasound parameters (peak intensity (PI), time to peak (TTP), and mean transit time (MTT)) of the two groups were compared. Then, multivariate logistic regression was used to analysis the results, and receiver operating characteristic (ROC) curves were plotted to evaluate the value of risk factors in predicting CLNM.

RESULTS

The transfer group showed notably lower PI, TTP and MTT than the non-transfer group (P<0.001), and focus diameter, microcalcification, multiple foci, PI, TTP, and MTT were identified as independent risk factors for LNM in patients (P<0.05). According to the ROC curve, the areas under the curves (AUCs) of microcalcification, multiple foci, and PI were all smaller than 0.7; the AUCs of focus diameter and MTT were smaller than 0.8, and the AUC of TTP was 0.855.

CONCLUSION

PI, TTP, and MTT all decrease in PTC patients with CLNM, and TTP has a strong predictor for CLNM in them, with an AUC of 0.855.