Impact of using elastic stains for detection of venous invasion in the prognosis of patients with lymph node negative colorectal cancer

Abstract

Patients with nodal negative colorectal cancer (CRC) suffer recurrent or metastatic disease in 40% of cases after surgical resection. To investigate a potential prognostic impact of vascular tumor infiltration, we retrospectively analyzed 185 nodal negative stage I and II CRC specimens for the presence of intra- and/or extramural venous invasion (V1IM/V1EM) using elastic stains of all tumor sections and correlated our findings with the clinical follow-up. Venous invasion was observed in 43 (23.2%) patients by elastic stains compared with six (3.2%) using HE only (p < 0.05). Venous invasion was more common in stage II than in stage I tumors (28.1% versus 5.1%; p < 0.05). However, survival analyses showed no significant differences in 5-year survival rates comparing patients with and without venous invasion (68% and 71%, p = 0.543) or patients with V1IM and V1EM (62% vs. 74%, p = 0.473), respectively. Our data emphasize the need for standardized criteria, including elastic stains, to reliably detect vascular invasion in CRC. Doing so, however, the prognostic impact of venous invasion in stage I and II CRC may be lower as previously anticipated.