Prediction of Lymphovascular Invasion in Rectal Cancer by Preoperative CT

OBJECTIVE. The purpose of this study was to investigate whether the diameter of superior hemorrhoidal vein on preoperative CT can predict the presence of lymphovascular invasion (LVI). SUBJECTS AND METHODS. This study recruited 102 patients with treatment-naive rectal cancers. The diameters of superior hemorrhoidal vein and inferior mesenteric vein (IMV) on pretreatment CT and postoperative pathologic reports were reviewed. Univariate analysis and receiver operating characteristic curve analysis were applied to determine the correlation between clinical factors and pathologic features and the diameters of superior hemorrhoidal vein and IMV. RESULTS. The diameter of superior hemorrhoidal vein was significantly higher in patients with LVI than in those without (mean diameter, 44 vs 30 mm, respectively; p < 0.001) and was significantly higher in patients with distant metastases than in those without (p = 0.044). There was no significant difference between IMV diameter in LVI and that in distant metastasis (p = 0.521). CONCLUSION. Patients having rectal cancers with LVI showed a significantly increased mean superior hemorrhoidal vein diameter at presentation, which could be identified with pretreatment CT and help to direct the application of neoadjuvant treatment strategies.