Elastica Staining for Venous Invasion Results in Superior Prediction of Cancer-Specific Survival in Colorectal Cancer

In Brief Objective: To examine the prognostic implications of routine elastica staining for venous invasion on prediction of cancer-specific survival in colorectal cancer. Summary Background Data: Venous invasion is an important high risk feature in colorectal cancer, although prevalence in published studies ranges from 10% to 90%. To resolve the disparity, elastica stains have been used in our institution to provide a more objective judgment since 2002. Methods: The study included 419 patients undergoing curative elective colorectal cancer resection between 1997 and 2006. Patients were grouped prior to (1997–2001 [cohort 1]) and following the introduction of elastica staining (2003–2006 [cohort 2]). Findings: Clinicopathologic characteristics and 3-year survival rates were similar in both groups. Rate of detected venous invasion increased from 18% to 58% following introduction of elastica staining (P< 0.001). The 3-year cancer-specific survival rate associated with the absence of venous invasion was 84% in cohort 1, compared with 96% in cohort 2 (P< 0.01). Elastica staining improved the prognostic value of venous invasion, showing the area under the receiver operator curve rising from 0.59 (P = 0.040; 1997–2001) to 0.68 (P< 0.001; 2003–2006), using cancer mortality as an end point. A direct comparison between H&E alone and elastica Hematoxylin and Eosin (H&E) was made in 53 patients. The area under the receiver operator curve increased from 0.58, P = 0.293 (H&E alone) to 0.74, P = 0.003 for venous invasion detected using the elastica method. Conclusions: Increased detection of venous invasion with elastica staining, compared with H&E staining, provides superior prediction of cancer survival in colorectal cancer. This relationship was seen in the comparison of 2 consecutive cohorts and in a direct comparison in a single cohort. Based on these results, elastica staining should be incorporated into the routine pathologic assessment of venous invasion in colorectal cancer. Venous invasion is a high risk feature in colorectal cancer. Routine staining of colorectal cancer specimens with elastica can improve rates of detection of venous invasion. Increased detection of venous invasion with elastica, compared with H&E staining alone, provides superior prediction of cancer survival. This relationship was seen in the comparison of two consecutive cohorts and in a direct comparison in a single cohort.