Computed Tomography-Detected Central Lymph Node Metastasis in Ultrasonography Node-Negative Papillary Thyroid Carcinoma: Is It Really Significant?
BACKGROUND
Because of the limitations in ultrasonography (US), the advantages of computed tomography (CT) for detecting central lymph node (LN) metastasis have been suggested in papillary thyroid carcinoma (PTC).


METHODS
First, we compared the diagnostic accuracy of US and CT for detecting central LN metastasis in 6577 central neck levels from 3668 PTC patients. Second, to examine the clinical impact of CT-detected central LN metastasis (CT cN1a) in PTC patients with clinically node negative in US (US cN0), we selected two groups: group I comprised 1245 US cN0 PTC patients who did not have CT scans and did not undergo central neck dissection (CND), while group II comprised 348 US cN0 and CT cN1a PTC patients who underwent CND. After propensity score matching, 254 matched pairs were yielded.


RESULTS
For detecting central LN metastasis, CT showed significantly higher sensitivity (38.9 vs. 27.5 %; p < 0.001) and accuracy (66.1 vs. 63.2 %; p < 0.001) than US. Furthermore, US + CT showed significantly higher sensitivity (47.8 vs. 27.5 %; p < 0.001) and accuracy (69.0 vs. 63.2 %; p < 0.001) than US. After matching, radioactive iodine ablation (81.5 vs. 85.8 %; p = 0.235) and locoregional recurrence (p = 0.663) were not significantly different between groups I and II.


CONCLUSIONS
Despite the diagnostic advantages of preoperative CT, 'CT-based CND' in US cN0 PTC patients did not significantly influence postoperative management and locoregional recurrence. The strategy for the management of central neck in PTC patients can be sufficiently determined by US only.
Division of Breast and Endocrine Surgery, Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
Seo Ki
SK
Kim
Department of Surgery, Changwon Gyeongsang National University Hospital, Gyeongsang National University School of Medicine, Changwon, South Korea.
Jung-Woo
JW
Woo
Division of Breast and Endocrine Surgery, Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
Inhye
I
Park
Division of Breast and Endocrine Surgery, Department of Surgery, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, South Korea.
Jun Ho
JH
Lee
Division of Breast and Endocrine Surgery, Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
Jun-Ho
JH
Choe
Division of Breast and Endocrine Surgery, Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
Jung-Han
JH
Kim
Division of Breast and Endocrine Surgery, Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea. jskim0126@skku.edu.
Jee Soo
JS
Kim
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002291:Carcinoma, Papillary / Q000000981:diagnostic imaging / Q000556:secondary* / Q000601:surgery; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008198:Lymph Nodes / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D011379:Prognosis; D012189:Retrospective Studies; D013964:Thyroid Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014463:Ultrasonography / Q000379:methods*; D055815:Young Adult