Relationship Between the Size of Metastatic Lymph Nodes and Positron Emission Tomographic/Computer Tomographic Findings in Patients with Esophageal Squamous Cell Carcinoma.
BACKGROUND
We measured the sizes of metastatic lymph nodes and the relationships thereof by (18)F-fluorodeoxyglucose positron emission tomography/computer tomography (PET/CT). We identified risk factors for nodal upstaging in patients with esophageal squamous cell carcinoma (ESCC).


METHODS
Eighty-five patients with ESCC who underwent esophagectomy with extensive mediastinal lymphadenectomy were assessed. Two radiologists blinded to pathology data reviewed PET/CT scans, evaluating both primary tumors and lymph node involvement. A pathologist examined all metastatic lymph nodes in terms of maximal diameter (LNmax), the size of the metastatic focus (Fmax), and the metastasis occupation ratio (MOR = Fmax/LNmax).


RESULTS
The maximal tumor length averaged 2.9 ± 0.2 cm and the mean SUVmax of the primary lesion 5.3 ± 0.5. On PET/CT scans, 26 (30.6 %) patients exhibited nodal metastasis and 59 (69.4 %) did not. Pathology grades of pN0, pN1, pN2, and pN3 were assigned to 45 (52.9 %), 24 (28.2 %), 13 (15.3 %), and 3 (3.5 %) patients, respectively. Nodal upstaging was evident in 29 (34.1 %) cases. In 123 metastatic nodes of 4212 nodes dissected, the LNmax was 6.60 ± 0.39 mm, the Fmax 4.47 ± 0.35 mm, and the MOR 0.68 ± 0.03. Of 123 nodes, 85 (69.1 %) were retrieved from PET-negative stations, and the LNmax and Fmax values of these nodes were 5.88 ± 0.42 and 3.75 ± 0.31 mm, respectively. Upon multivariate analysis, tumor length (OR 1.666, p = 0.019) and lymphovascular invasion (OR 41.038, p < 0.001) were risk factors for nodal upstaging.


CONCLUSIONS
A significant proportion of nodal metastases were too small to detect via PET/CT imaging. Therefore, meticulous lymph node dissection might be helpful in ESCC patients.
Department of Thoracic and Cardiovascular Surgery, Yonsei University, College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul, 120-752, Republic of Korea. psy1117@hanmail.net.
Seong Yong
SY
Park
Department of Thoracic and Cardiovascular Surgery, Yonsei University, College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul, 120-752, Republic of Korea. kdjcool@yuhs.ac.
Dae Joon
DJ
Kim
Department of Thoracic and Cardiovascular Surgery, Yonsei University, College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul, 120-752, Republic of Korea. hsjung80@yuhs.ac.
Hee Suk
HS
Jung
Department of Nuclear Medicine, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul, Republic of Korea. yunmijin@yuhs.ac.
Mi Jin
MJ
Yun
Department of Nuclear Medicine, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul, Republic of Korea. jwlee223@ish.or.kr.
Jeong Won
JW
Lee
Department of Pathology, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul, Republic of Korea. pck0111@yuhs.ac.
Cheol Keun
CK
Park
D001808:Blood Vessels / Q000473:pathology; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis* / Q000601:surgery; D004938:Esophageal Neoplasms / Q000175:diagnosis* / Q000601:surgery; D000077277:Esophageal Squamous Cell Carcinoma; D016629:Esophagectomy; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000000981:diagnostic imaging* / Q000473:pathology; D008207:Lymphatic Metastasis; D042601:Lymphatic Vessels / Q000473:pathology; D008297:Male; D008482:Mediastinum; D008875:Middle Aged; D064847:Multimodal Imaging; D060787:Neoplasm Grading; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D012307:Risk Factors; D014057:Tomography, X-Ray Computed; D047368:Tumor Burden
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18