Lymphatic vessel density at the site of deepest penetration as a predictor of lymph node metastasis in submucosal colorectal cancer.
OBJECTIVE
Lymph node metastasis is an important factor that influences curability after endoscopic treatment of submucosal colorectal cancer. This study was designed to determine the usefulness of identification of lymphatic vessels by immunohistochemistry in predicting lymph node metastasis of submucosal colorectal cancer.


METHODS
Lymphatic involvement was assessed by hematoxylin and eosin staining and podoplanin immunostaining on samples resected from 268 patients with submucosal colorectal cancer. Lymphatic vessel density was estimated by two investigators by average count of three fields (x200) in the area of greatest number of podoplanin-positive capillaries at the site of deepest submucosal penetration. Relations with other clinicopathologic parameters also were investigated.


RESULTS
Lesions with high lymphatic vessel density (> or =9 vessels per field) showed a significantly greater incidence of lymph node metastasis than did those with low lymphatic vessel density (<9 vessels per field; 23.3 vs. 8.4 percent). By multivariate analysis, lymphatic vessel density was determined to be an independent risk factor for lymph node metastasis of submucosal colorectal cancer (P = 0.0044). Lymphatic vessel density also correlated with tumor budding and the degree of inflammation at the invasive front.


CONCLUSIONS
Identification of lymphatic vessels by podoplanin immunostaining provides objective and accurate evaluation of lymphatic involvement. Lymphatic vessel density at the site of deepest penetration is a useful predictor of lymph node metastasis of submucosal colorectal cancer.
Kaneko
Iwao
I
Department of Medicine and Molecular Science, Hiroshima University Graduate School of Biomedical Science, Hiroshima, Japan.
Tanaka
Shinji
S
Oka
Shiro
S
Kawamura
Toru
T
Hiyama
Toru
T
Ito
Masanori
M
Yoshihara
Masaharu
M
Shimamoto
Fumio
F
Chayama
Kazuaki
K
D015179:Colorectal Neoplasms / Q000473:pathology*; D004801:Eosine Yellowish-(YS); D005260:Female; D006416:Hematoxylin; D006801:Humans; D007124:Immunoenzyme Techniques; D016015:Logistic Models; D008207:Lymphatic Metastasis; D042601:Lymphatic Vessels / Q000473:pathology*; D008297:Male; D008562:Membrane Glycoproteins; D009361:Neoplasm Invasiveness; D009389:Neovascularization, Pathologic / Q000473:pathology*; D012307:Risk Factors; D018709:Statistics, Nonparametric; D000098853:Podoplanin
D004801:Eosine Yellowish-(YS); D006416:Hematoxylin; D008562:Membrane Glycoproteins; C117468:PDPN protein, human; D000098853:Podoplanin