Yonsei Med J.  2016 Nov;57(6):1324-1328. 10.3349/ymj.2016.57.6.1324.

Prognostic Value of Extranodal Extension in Thyroid Cancer: A Meta-Analysis

• Suh S
• Pak K
• Seok JW
• Kim IJ

• KMID: 2427148
• DOI: http://doi.org/10.3349/ymj.2016.57.6.1324

Abstract

PURPOSE
Thyroid cancer is the most common endocrine cancer and its incidence has continuously increased in the last three decades all over the world. We aimed to evaluate the prognostic value of extranodal extension (ENE) of thyroid cancer.
MATERIALS AND METHODS
We performed a systematic search of MEDLINE (from inception to June 2014) and EMBASE (from inception to June 2014) for English-language publication. The inclusion criteria were studies of thyroid cancer that reported the prognostic value of ENE in thyroid cancer. Reviews, abstracts, and editorial materials were excluded, and duplicate data were removed. Two authors performed the data extraction independently.
RESULTS
6 studies including 1830 patients were eligible for inclusion in the study. All patients included in the meta-analysis had papillary thyroid cancer (PTC). Recurrence-free survival was analyzed based on 3 studies. The pooled hazard ratio for recurrence was 2.01 [95% confidence interval (CI) 1.19-3.40, p=0.009]. Disease-specific survival was analyzed based on 3 studies with 973 patients. Patients of PTC with ENE showed 3.37-fold higher risk of death from the disease (95% CI 1.55-7.32, p=0.002).
CONCLUSION
ENE should be considered to be a poor prognostic marker in thyroid cancer; such knowledge might improve the management of individual patients. This might facilitate the planning of appropriate ablation therapy and tailored patient follow-up from the beginning of treatment.

Keyword

Thyroid carcinoma; lymph nodes; prognosis

MeSH Terms

Carcinoma/*mortality/*secondary/surgery
Carcinoma, Papillary
Disease-Free Survival
Humans
Lymph Node Excision
Lymph Nodes/*pathology/surgery
Lymphatic Metastasis
Male
Neoplasm Recurrence, Local/mortality/*pathology/surgery
Prognosis
Proportional Hazards Models
Risk
Thyroid Neoplasms/*mortality/*pathology/secondary/surgery
Thyroidectomy
Treatment Outcome

Figure

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  Fig. 1 Flowchart of the study selection process.

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  Fig. 2 Forest plots of the hazard ratios for recurrence. CI, confidence interval; SE, standard error.

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  Fig. 3 Forest plots of hazard ratios for deaths from thyroid cancer. CI, confidence interval; SE, standard error.

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