The important risk factor for lateral pelvic lymph node metastasis of lower rectal cancer is node-positive status on magnetic resonance imaging: study of the Lymph Node Committee of Japanese Society for Cancer of the Colon and Rectum

• Published in: International journal of colorectal disease Vol. 31; no. 10; pp. 1719 - 1728
• Main Authors: Ogawa, Shimpei, Hida, Jin-ichi, Ike, Hideyuki, Kinugasa, Tetsushi, Ota, Mitsuyoshi, Shinto, Eiji, Itabashi, Michio, Okamoto, Takahiro, Sugihara, Kenichi
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.10.2016; Springer; Springer Nature B.V
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; Area Under Curve; Cancer; Colorectal cancer; Female; Gastroenterology; Hepatology; Humans; Internal Medicine; Lymph Nodes - pathology; Lymphatic Metastasis - pathology; Magnetic Resonance Imaging; Male; Medicine; Medicine & Public Health; Metastasis; Middle Aged; Multivariate Analysis; Oncology, Experimental; Original Article; Proctology; Rectal Neoplasms - pathology; Risk Factors; Societies, Medical; Surgery; Young Adult; Magnetic resonance imaging (MRI); Rectal cancer; Lateral pelvic lymph node (LPLN); Perirectal lymph node (PRLN)
• ISSN: 0179-1958; 1432-1262; 1432-1262
• DOI: 10.1007/s00384-016-2641-3

Purpose This study seeks to evaluate lateral pelvic lymph node (LPLN) and perirectal lymph node (PRLN) status on magnetic resonance imaging (MRI) as potential risk factors for lymph node metastasis. Methods The subjects were 394 patients with lower rectal cancer who underwent MRI prior to mesorectal excision (combined with lateral pelvic lymph node dissection in 272 patients) at 6 institutes. No patients received neoadjuvant therapy. Cases were classified as cN(+) and cN(−) based on the short axis of the largest lymph node ≥5 and <5 mm, respectively. LPLN and PRLN status and other clinicopathologic factors were analyzed by multivariate logistic regression. The importance of identified risk factors for lymph node metastasis was examined using the area under the curve (AUC). Results Independent risk factors for right LPLN metastasis included histopathological grade (G3 + G4), pPRLN(+), M1, cLPLN(+) [odds ratio (OR) 10.73, 95 % confidence interval (CI) 4.59–27.1], and those for left LPLN metastasis were age (<64), histopathological grade (G3 + G4), pPRLN(+), and cLPLN(+) (OR 24.53, 95 % CI 9.16–77.7). ORs for cLPLN(+) were highest. The AUCs for right and left cLPLN status of 0.7484 (95 % CI 0.6672–0.8153) and 0.7904 (95 % CI 0.7088–0.8538), respectively, were significantly higher than those for other risk factors. In contrast, the ORs for cPRLN(+) and cPRLN status of 2.46 (95 % CI 1.47–4.18) and 0.6396 (95 % CI 0.5917–0.6848) were not much higher than for other factors. Conclusions An LPLN-positive status with a short axis ≥5 mm on MRI is an important predictor of LPLN metastasis, but PRLN status is not a strong predictor of PRLN metastasis.