Area of submucosal invasion and width of invasion predicts lymph node metastasis in pT1 colorectal cancers.
BACKGROUND
The prediction of lymph node metastasis by current histopathological methods is imprecise.


OBJECTIVE
The aim of this study was to evaluate currently used and possible new high-risk features associated with lymph node metastasis to identify the markers of lymph node metastasis.
Two hundred seven pT1 cancers were identified through the Northern and Yorkshire Cancer Registry and Information Services database and digitally scanned. Phenotypic and quantitative features of the pT1 cancers were evaluated. Lymph node metastasis and high-risk feature status were obtained through pathology reports of resections, and high-risk phenotypic features were identified.


RESULTS
Lymph node metastasis was noted in 19 patients (9.2%). pT1 cancers with lymph node metastasis had a significantly wider area of invasion (p = 0.001) and greater area of submucosal invasion (p < 0.001) compared with pT1 cancers without lymph node metastasis. Qualitative features such as grade of differentiation and vascular and lymphatic invasion were significant predictors of lymph node metastasis (p < 0.0001, p = 0.039, and p = 0.018). Modified receiver-operating characteristics curves generated cutoff values of 11.5 mm for the width of invasion and 35 mm(2) for the area of submucosal invasion. When tested separately with other qualitative factors on multivariate analysis, both width greater than 11.5 mm (OR, 12.12; 95% CI, 2.19-67.23; p = 0.004) and area of submucosal invasion greater than 35 mm(2) (OR, 22.44; 95% CI, 2.7-186.63; p = 0.004) was predictive of lymph node metastasis.


CONCLUSIONS
This is a retrospective study and is limited by its small sample size.


CONCLUSIONS
This study has shown that the width and area of submucosal invasion are potential predictors of lymph node metastasis and superior to the depth of invasion. Together with the other qualitative phenotypic features, these quantitative factors could be used to decide the most appropriate treatment for pT1 cancers.
1 Pathology and Tumour Biology, Leeds Institute of Cancer and Pathology, University of Leeds, Leeds, United Kingdom 2 Academic Foundation Year 2, St James's University Hospital, Leeds, United Kingdom 3 Cancer Epidemiology Group, St Jame's Institute of Oncology, Leeds, United Kingdom 4 John Goligher Colorectal Unit, St James's University Hospital, Leeds, United Kingdom.
Eu-Wing
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Toh
Peter
P
Brown
Eva
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Morris
Ian
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Botterill
Philip
P
Quirke
D000230:Adenocarcinoma / Q000556:secondary*; D000236:Adenoma / Q000473:pathology*; D000368:Aged; D015179:Colorectal Neoplasms / Q000473:pathology*; D005260:Female; D006801:Humans; D007413:Intestinal Mucosa / Q000473:pathology*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D015588:Observer Variation; D011379:Prognosis; D012372:ROC Curve; D012189:Retrospective Studies; D012307:Risk Factors