Predictive factors and pattern of locoregional recurrence after prophylactic central neck dissection in papillary thyroid carcinoma.

BACKGROUND: Prophylactic central neck dissection (pCND) at the time of the total thyroidectomy (TT) remains controversial in clinically nodal-negative (cN0) papillary thyroid carcinoma. Our study was designed to examine the predictive factors and pattern of locoregional recurrence (LRR) after pCND in the context of the postoperative stimulated Tg (sTg) level. METHODS: A total of 341 patients who underwent TT and unilateral pCND were analyzed. Patients with an identifiable lesion on ultrasonography or whole-body scan within 6 months of surgery were excluded. LRR was defined as an identifiable lesion on USG, which was later confirmed by cytology/histology. Preablation sTg level was taken 2 months after surgery, whereas postablation sTg level was taken 8 months after surgery. Cox regression was used in the univariate and multivariate analyses to identify significant independent factors for LRR. RESULTS: After a follow-up of 66.6 ± 38.6 months, 14 (4.1 %) suffered from LRR. The duration to first LRR was 36.4 ± 21.7 months. The estimated 5- and 10-year LRR rates were 5.1 and 6.1 %, respectively. Of these 14 LRR, 3 (21.4 %) involved the central compartment alone, 9 (64.3 %) involved the lateral compartment alone, and 2 (14.3 %) involved both central and lateral compartments. After adjusting for other clinicopathological factors, postablation sTg level ≥ 1 µg/L (hazard ratio 265.109, 95 % confidence interval 1.132-62075.644, p = 0.045) was the only independent predictor of LRR. CONCLUSIONS: Annualized risk of LRR after pCND was approximately 1 % in the first 5 years and 0.2 % in the subsequent 5 years. Most (78.6 %) LRRs involved the lateral compartment. Postablation sTg ≥ 1 µg/L significantly predicted risk of LRR.

Does preoperative neutrophil lymphocyte ratio predict risk of recurrence and occult central nodal metastasis in papillary thyroid carcinoma?

BACKGROUND: Preoperative neutrophil to lymphocyte ratio (NLR) might be prognostic in papillary thyroid carcinoma (PTC). Given the controversy of prophylactic central neck dissection (pCND) in clinically nodal-negative (cN0) PTC, our study evaluated whether preoperative NLR predicted disease-free survival (DFS) and occult central nodal metastasis (CNM) in cN0 PTC. METHODS: A total of 191 patients who underwent pCND were analyzed. Complete blood counts with differential counts were taken before operation. NLR was calculated by dividing preoperative neutrophil count with lymphocyte count. Patients were categorized into NLR tertiles: first (NLR < 1.93; n = 63), second (NLR = 1.93-2.79; n = 64), and third tertile (NLR > 2.79; n = 64). Four other patient types, namely, benign nodular goiter, clinically nodal-positive (cN1) PTC, poorly differentiated thyroid carcinoma, and anaplastic thyroid carcinoma (ATC), were used as references. RESULTS: Age at operation (p < 0.001) and tumor size (p = 0.037) significantly increased with higher NLR. First tertile had significantly more TNM stage I tumors (p = 0.01) and lowest MACIS score (p = 0.002). Tumor size [hazard ratio (HR) 1.422, 95% confidence interval (CI) 1.119-1.809, p = 0.004] and multicentricity (HR = 2.545, 95% CI 1.073-6.024, p = 0.034) independently predicted DFS, whereas old age [odds ratio (OR) 1.026, 95% CI 1.006-1.046, p = 0.009), male (OR 2.882, 95% CI 1.348-6.172, p = 0.006), and large tumor (OR 1.567, 95% CI 1.209-2.032, p = 0.001) independently predicted occult CNM. NLR was not significantly associated with DFS or occult CNM. ATC had significantly higher NLR than cN1 PTC (7.28 vs. 2.74, p < 0.001). CONCLUSIONS: Although a higher NLR may imply a poorer tumor profile, it was not significantly associated with a worse DFS or higher risk of occult CNM in cN0 PTC. Perhaps, future research should focus on the prognostic value in other thyroid cancer types with a poorer prognosis.