GEWF solution

Lymph node status is an important prognostic factor in the staging of colorectal carcinoma. Several adjunctive solutions have been used to increase the yield of pericolic lymph nodes from colorectal cancer resection specimens.

During 1998 at the Grey Bruce Regional Health Centre (Owen Sound, Ontario), 67 colonic resections were performed for colorectal cancer. Lymph nodes were identified using GEWF solution (glacial acetic acid, ethanol, distilled water, and formaldehyde) in 35 cases, and by the conventional method of sectioning, inspection, and palpation in 32 cases.

There were no significant differences between GEWF and non-GEWF cases with respect to patient age, length of resection, size of tumor, tumor histologic type, tumor differentiation, or depth of tumor penetration into the bowel wall. Use of GEWF led to a significant increase in the number of lymph nodes found (10.2 +/- 4.9 per case) compared with non-GEWF cases (6.8 +/- 3.9 per case) (P =.002). In GEWF cases 358 lymph nodes were identified, 82 with metastases, whereas in the non-GEWF cases 218 lymph nodes were found, 41 with metastases. The size of positive lymph nodes in the GEWF group (0.5 +/- 0.2 cm) was significantly smaller than in the non-GEWF group (0.7 +/- 0.4 cm) (P =.046). A greater percentage of positive lymph nodes in the GEWF cases (49/82, 60%) were 0.5 cm or smaller compared with the non-GEWF cases (17/41, 41%).

GEWF increases the yield of lymph nodes recovered from colorectal cancer specimens and may lead to improved staging of this cancer; it is inexpensive and simple to use.