# Prospective Observational Study of the Role of Unilateral Prophylactic Central Compartmental Lymph Node Dissection in Early Papillary Thyroid Cancer

## TL;DR

This study examines if one-sided lymph node removal in early thyroid cancer helps detect hidden spread while minimizing complications.

## Contribution

The study introduces unilateral lymph node dissection as a potential compromise to reduce risks while identifying occult metastases in early thyroid cancer.

## Key findings

- Occult central nodal metastasis was found in 40% of patients.
- Most metastases were on the same side as the tumor, with no contralateral-only cases.
- Complications like hypocalcaemia and nerve dysfunction were mostly transient.

## Abstract

Background: In clinically node-negative (cN0) early papillary thyroid carcinoma (PTC), prophylactic central compartment lymph node dissection (PCND) remains debated because occult nodal upstaging may not translate into improved recurrence outcomes and may increase hypocalcaemia and recurrent laryngeal nerve injury. Unilateral dissection may provide a risk-limiting compromise.

Methods: This prospective single-centre study included 50 consecutive adults with T1 or T2 cN0 PTC who underwent total thyroidectomy with unilateral central compartment lymph node dissection on the tumour side. The primary outcome was occult level VI nodal metastasis and laterality pattern. Secondary outcomes included perioperative complications, particularly hypocalcaemia or hypoparathyroidism, and recurrent laryngeal nerve dysfunction.

Results: Occult central nodal metastasis was detected in 40.0% (20 of 50; 95% CI 27.6 to 53.8), resulting in pN1a upstaging. Among node-positive cases, 90.0% (18 of 20) were ipsilateral only, and 10.0% (two of 20) showed bilateral involvement in labelled tissue, with no contralateral-only disease observed. On univariable analysis, nodal positivity was associated with tumour size greater than 2 cm, capsular invasion, and multifocality. Transient hypocalcaemia occurred in 38.0% and permanent hypocalcaemia in 2.0. % Transient recurrent laryngeal nerve dysfunction occurred in 10.0% and permanent dysfunction in 2.0%. The mean postoperative stay was 3.6 days. No locoregional recurrence was detected during short-term surveillance of about 12 months.

Conclusion: In this single-centre cohort, unilateral PCND identified occult level VI disease in a substantial proportion of selected early cN0 PTC, with low permanent morbidity, but laterality interpretation and oncologic inference are limited by specimen labelling constraints and short follow-up, so the findings are hypothesis-generating and require validation in larger comparative studies.