Yoon Kyoung So1, Min-Ji Kim2, Seonwoo Kim2, Young-Ik Son3. 1. Department of Otorhinolaryngology-Head and Neck Surgery, Ilsan Paik Hospital, Inje University College of Medicine, Goyang, Republic of Korea. 2. Statistics and Data Center, Research Institute for Future Medicine, Samsung Medical Center, Seoul, Republic of Korea. 3. Department of Otorhinolaryngology-Head and Neck Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea. Electronic address: yison@skku.edu.
Abstract
BACKGROUND: Lymph node metastasis (LNM) is frequent in papillary thyroid carcinoma (PTC) and is associated with a poor prognosis. Unlike central LNM (CLNM), there are few studies focusing on LLNM. We aimed to investigate the prevalence and the risk factors for LLNM, with its most prevalent sites. METHODS: We performed a comprehensive literature search using the PubMed and EMBASE databases for relevant studies published prior to November 2016 that examined the risk factors for LLNM. RESULTS: Twenty-three studies, including 18,741 patients, were included. The prevalence of LLNM was 20.9% in all patients. CLNM (pooled OR = 7.84, 95% CI = 6.13-10.02, p < .0001), extrathyroidal extension (pooled OR = 3.22, 95% CI = 2.21-4.70, p < .0001), tumor multifocality (pooled OR = 2.19, 95% CI = 1.67-2.89, p < .0001), male sex (pooled OR = 1.72, 95% CI = 1.50-1.98, p < .0001), upper pole location (pooled OR = 2.96, 95% CI = 1.93-4.53, p < .0001), tumor size ≥1.0 cm (pooled OR = 2.49, 95% CI = 1.71-3.61, p < .0001), lymphovascular invasion (pooled OR = 3.96, 95% CI = 2.61-6.03, p < .0001) and tumor bilaterality (pooled OR = 1.31, 95% CI = 1.12-1.53, p = .0006) were significantly associated with LLNM. Most frequently affected areas were levels III and IV. CONCLUSIONS: The prevalence of LLNM was high although the prognostic impact is unknown. The significant risk factors for LLNM were not much different from known risk factors for CLNM.
BACKGROUND: Lymph node metastasis (LNM) is frequent in papillary thyroid carcinoma (PTC) and is associated with a poor prognosis. Unlike central LNM (CLNM), there are few studies focusing on LLNM. We aimed to investigate the prevalence and the risk factors for LLNM, with its most prevalent sites. METHODS: We performed a comprehensive literature search using the PubMed and EMBASE databases for relevant studies published prior to November 2016 that examined the risk factors for LLNM. RESULTS: Twenty-three studies, including 18,741 patients, were included. The prevalence of LLNM was 20.9% in all patients. CLNM (pooled OR = 7.84, 95% CI = 6.13-10.02, p < .0001), extrathyroidal extension (pooled OR = 3.22, 95% CI = 2.21-4.70, p < .0001), tumor multifocality (pooled OR = 2.19, 95% CI = 1.67-2.89, p < .0001), male sex (pooled OR = 1.72, 95% CI = 1.50-1.98, p < .0001), upper pole location (pooled OR = 2.96, 95% CI = 1.93-4.53, p < .0001), tumor size ≥1.0 cm (pooled OR = 2.49, 95% CI = 1.71-3.61, p < .0001), lymphovascular invasion (pooled OR = 3.96, 95% CI = 2.61-6.03, p < .0001) and tumor bilaterality (pooled OR = 1.31, 95% CI = 1.12-1.53, p = .0006) were significantly associated with LLNM. Most frequently affected areas were levels III and IV. CONCLUSIONS: The prevalence of LLNM was high although the prognostic impact is unknown. The significant risk factors for LLNM were not much different from known risk factors for CLNM.
Authors: Emilien Chebib; Caroline Eymerit; Nathalie Chabbert-Buffet; Bruno Angelard; Jean Lacau St Guily; Sophie Périé Journal: Gland Surg Date: 2020-12