Prognostic Value of Tumor Multifocality in Pediatric Papillary Thyroid Carcinoma: A Real-Life Multicentric Study

Area of Science:

• Endocrinology
• Pediatric Oncology
• Surgical Oncology

Background:

• Papillary thyroid cancer (PTC) is the most common endocrine malignancy in children and adolescents.
• Tumor multifocality, the presence of multiple distinct tumor foci, is a recognized feature of PTC, but its prognostic significance in pediatric cases remains debated.
• Understanding factors influencing clinical outcomes is crucial for optimizing treatment strategies in pediatric PTC.

Purpose of the Study:

• To investigate the association between tumor multifocality and clinical outcomes, specifically disease-free survival (DFS), in pediatric patients with papillary thyroid cancer.
• To determine if tumor multifocality is an independent risk factor for persistent or recurrent disease in this population.

Main Methods:

• A multicenter retrospective study utilizing prospectively collected data from three tertiary hospitals in China.
• Inclusion criteria comprised patients aged 18 years or younger diagnosed with PTC who underwent total thyroidectomy and radioiodine ablation between 2005 and 2020.
• Disease-free survival (DFS) was defined as the absence of persistent or recurrent disease, with analysis conducted using Cox proportional hazards regression models.

Main Results:

• The study included 173 pediatric patients (median age 16 years), with multifocal disease identified in 34.1% (59 patients).
• After a median follow-up of 57 months, 36.4% (63 patients) experienced persistent disease.
• While univariable analysis showed a significant association between multifocality and decreased DFS (HR=1.90, p=0.01), this association lost statistical significance after multivariate adjustment (HR=1.20, p=0.55). Subgroup analysis of clinically M0 patients also yielded non-significant results.

Conclusions:

• In a highly selected cohort of pediatric patients with papillary thyroid cancer undergoing surgery, tumor multifocality was not found to be an independent risk factor for decreased disease-free survival.
• These findings suggest that multifocality alone may not significantly impact long-term outcomes in pediatric PTC when other clinical factors are considered.