[Clinical significance of lymphatic metastasis between sternocleidomastoid and sternohyoid muscle in papillary thyroid cancer].

Objective: To explore the clinical significance of metastasis of lymph nodes between sternocleidomastoid and sternohyoid muscle (LNSS) in papillary thyroid cancer (PTC). Methods: A total of 175 patients with PTC who underwent thyroidectomy with LNSS dissection were retrospectively analyzed. Univariate and multivariate Logistic regression analyses were used to determine the independent risk factors for LNSS metastasis in PTC. Results: The rate of detectable LNSS was 70.9% (124/175) and metastasis rate was 7.4% (13/175). Of 13 cases with LNSS metastasis, 10 with the coexistence of cervical lymph node metastasis. Univariate Logistic regression analysis showed that multiple focal cancer, tumor located in the lower pole of thyroid, belt-shaped muscle invasion, lateral cervical lymph node metastasis, cN+ , the number of cervical lymph nodes with metastasis and the number of lymph nodes with metastasis in level Ⅳwere the risk factors for LNSS metastasis (P<0.05). Multivariate Logistic regression analysis suggested that tumor located in the lower pole of thyroid and the number of cervical lymph nodes with metastasis >6 were the independent risk factors for LNSS metastasis (P<0.05). Given the number of cervical lymph nodes with metastasis as a predictor for the LNSS metastasis, the sensitivity was 92.3%, the specificity was 66.7% and the accuracy rate was 68.6%. Conclusions: LNSS metastasis is commom in PTC, with a metastasis rate of 7.4%. PTC in the lower pole of thyroid and the number of cervical lymph nodes with metastasis > 6 are independent risks for LNSS metastasis.

[The clinical significance of Delphian lymph node metastasis in papillary thyroid cancer].

Objective: To evaluate the clinical significance of Delphian lymph node (DLN) metastasis in papillary thyroid cancer (PTC). Method: A total of 505 cases with PTC confirmed pathologically in our hospital between January 2015 and December 2015 were retrospectively reviewed. 208 patients with DLN assessed separately by histopathologic examination who underwent primary surgery for PTC were included for the following analysis. Results: In 208 patients, the detection rate of DLN was 63.0% and the metastasis rate of DLN was 21.4%. DLN metastasis was correlated with PTC multifocality (P=0.038), tumor size over 1cm (P=0.001), BRAFV600E mutation (P=0.017) and central neck node metastasis (P<0.001). Tumor size over 1cm (95%CI 1.308-9.909, OR=3.600, P=0.013) and the number of node with central neck metastasis (95%CI 1.313-2.163, OR=1.685, P<0.001) were independent risk factors for DLN metastasis. The presence of DLN metastasis was associated with an 8.8-fold higher frequency of central neck node metastasis compared to cases without DLN metastasis. Among patients with DLN metastases, central lymph node metastasis was more common in the cases with lateral neck node metastases compared to those without lateral neck node metastases (6.5±3.0 vs 1.5±0.7, P=0.009), and 5 of the 6 patients also presented with PTC multifocality and BRAFV600E mutation. Conclusion: DLN metastasis implies a higher possibility of central neck lymph node metastasis. DLN should be assessed during operation to provide information for neck dissection, post-operative administration and follow-up strategy.