[Molecular subtyping and clinical characteristics of patients with reoperated papillary thyroid carcinoma].

Objective

To explore the reoperation cause and molecular classification of patients reoperated for papillary thyroid carcinoma (PTC).

Methods

This is a retrospective case series study. Clinical data from 102 PTC patients who underwent reoperation at the Department of Head and Neck Surgery, Sun Yat-sen University Cancer Center were collected between February 2019 and December 2024. The cohort comprised 26 males (25.5%) and 76 females (74.5%), with initial age of (33.1±12.2) years (range: 9 to 67 years). At initial surgery, 25.5% (26/102) exhibited extrathyroidal extension, 52.0% (53/102) had multifocal tumors, and 19.6% (20/102) had metastatic lymph nodes with extranodal extension. AJCC staging classified 95.1% (97/102) as stage Ⅰ, 2.9% (3/102) as stage Ⅱ, and 2.0% (2/102) as stage Ⅲ. Standardized primary tumor resection was performed in 81.4% (83/102), prophylactic central compartment lymph node dissection (LND) in 89.2% (91/102), and therapeutic lateral LND in 47.1% (48/102). Data on recurrence, genetic alterations, reoperation intervals, and clinical features of multiple recurrent PTC cases were analyzed.

Results

Among 102 patients, 81.4% (83/102) presented with lateral neck metastases, 48.0% (49/102) with central compartment metastases, and 22.6% (23/102) with residual thyroid lobe recurrence at reoperation. Reoperation occurred within 6 months postoperatively in 18.6% (19/102) and after 6 months in 81.4% (83/102). Genetic detection revealed BRAF mutation in 63.7% (65/102), RET fusions in 19.6% (20/102), and TERT promoter mutations in 8.8% (9/102). During reoperation, 88.2% (90/102) underwent therapeutic lateral LND, and 39.2% (40/102) required residual gland resection. Twelve patients received multiple surgeries, including 4 cases with BRAF+TERT mutations, 4 with RET fusions, and 4 with BRAF mutation alone.

Conclusions

The reasons for the reoperation of PTC mainly include recurrence and complementary surgery. Genetic alterations such as BRAF mutation and RET fusion are common in PTC patients requiring reoperation.