Prognostic Role of Histopathological Features in Pediatric Papillary Thyroid Carcinoma: Systematic Review and Meta-Analysis.

[OBJECTIVE] The aim of this study is to evaluate the impact of extrathyroidal extension (ETE), multifocality, and lateral neck lymph node metastasis on survival outcomes for pediatric patients with differentiated papillary thyroid carcinoma (PTC).

[METHODS] This study was conducted in conformity with the PRISMA statement. The pooled hazard ratios (HRs) and the 95% confidence interval (CI) were calculated to define the impact of different pathological factors on disease-free survival (DFS).

[RESULTS] A total of 13 studies, enrolling 2641 patients (males: 29.5%, n = 780) with a median age of 16 years (95% CI: 15.4-19.0) years (n = 1370/2641), were included. The incidence of multifocality and ETE was 30.7% (n = 806/2625), and 45.4% (n = 1148/2528), respectively. The incidence of lateral neck lymph node metastasis (LNM) was 51.6% (n = 1224/2372). Overall, 61.5% of patients underwent postoperative radioactive iodine therapy (RAI) (n = 1381/2247). The median follow-up time was 85 months (95% CI: 57.0-176.4) (n = 2534/2641). The estimated pooled HRs for DFS were 1.86 (95% CI: 1.33-2.59; p = 0.002) for multifocality, 1.78 (95% CI: 1.20-2.63; p = 0.010) for ETE and 1.77 (95% CI: 0.76-4.11; p = 0.161) for lateral neck LNM.

[CONCLUSIONS] Multifocality and ETE are significant predictors of recurrence in pediatric PTC, while lateral neck LNM does not seem to be a reliable prognostic factor. These results may warrant consideration in pediatric-specific risk stratification and help guide treatment and follow-up.