Low proliferative level is a poor prognostic factor for colon adenocarcinoma

Abstract

Aim. To match up the proliferative activity of colon adenocarcinoma cells with tumor stage and survival rate. Methods. Ki-67 protein expression was evaluated by immunohistochemical methods in 217 patients with primary colon adenocarcinoma. After epitope retrieval and endogenous peroxidase inhibiting by 3% solution of hydrogen peroxide, histologic samples were stained by antibodies to Ki-67 protein (clone SP6, dilution 1:300) and polymer systemic detection with diaminobenzidine as a chromogenic substrate. Nuclear counterstain was performed using Mayer’s hematoxylin solution. Results. Assessment of colon adenocarcinoma proliferative activity showed a significant difference between the number of cases with high (>70%) and relatively low (≤30%) proliferative levels in groups with metastatic cancers and non-metastatic tumors. In patients with no relapses, colon adenocarcinoma proliferative activity assessment showed proliferation level exceeding 70% in 21 (95%) out of 22 cases, in a single case proliferation level of 60% was found according to Ki-67, no cases of proliferation level lower than 50% was found. Statistical analysis showed that proliferative activity was significantly lower in patients with metastatic colon adenocarcinoma compared to cases of adenocarcinoma without metastases (p= 0.0019). We observe one clinical case of aggressive colon adenocarcinoma with omental, peritoneal, paraumbilical metastases in 28-year old patient, in whom proliferative activity by Ki-67 was measured as 20%. Conclusion. Low proliferative level in colon adenocarcinoma is a poor prognostic factor for possible metastasing and cancer recurrence.

Keywords

Ki-67 / Ki-67 / proliferation / colon adenocarcinoma / prognosis

RIGHTS & PERMISSIONS

Raskin G.A., Petrov S.V.