Analysis of Ki-67 expression in oral squamous cell carcinoma: Why Ki-67 is not a prognostic indicator

Gonzalez-Moles, M.A.; Ruiz-Avila, I.; Gil-Montoya, J.A.; Esteban, F.; Bravo, M.

doi:10.1016/j.oraloncology.2010.03.020

« Previous Next »Oral Oncology
Volume 46, Issue 7 , Pages 525-530, July 2010

Analysis of Ki-67 expression in oral squamous cell carcinoma: Why Ki-67 is not a prognostic indicator

M.A. Gonzalez-Moles
- Oral Medicine Department, School of Dentistry, University of Granada, Paseo de Cartuja s/n, 18071 Granada, Spain
- Corresponding author. Address: Facultad de Odontología, Paseo de Cartuja s/n, 18071 Granada, Spain. Tel.: +34 958243804; fax: +34 9582409080.
I. Ruiz-Avila
- Pathology Department, “Complejo Hospitalario”, Jaen. Avda Ejercito Español 10, 23007 Jaen, Spain
J.A. Gil-Montoya
- Oral Medicine Department, School of Dentistry, University of Granada, Paseo de Cartuja s/n, 18071 Granada, Spain
F. Esteban
- Otorhinolaryngology Department, Virgen del Rocio University Hospital, Sevilla, Avda Manuel Siurot s/n, 41013 Sevilla, Spain
M. Bravo
- Preventive and Public Health in Dentistry Department, School of Dentistry, University of Granada, Paseo de Cartuja s/n, 18071 Granada, Spain

Received 7 January 2010; received in revised form 16 March 2010; accepted 16 March 2010. published online 20 April 2010.

Summary

Objectives: To analyze the prognostic value of Ki-67 in oral cancer and its relationship with Ki-67 expression in precancerous epithelium. Material and methods: We studied 79 tumors from 65 patients. Immunohistochemistry study with Mib-1 monoclonal antibody was used to detect Ki-67 expression in tumor tissue and adjacent non-tumor tissue. The influence of different variables on survival was studied with univariate and multivariate analyses. Results: Ki-67 expression was significantly higher in well-differentiated versus poorly-differentiated carcinomas. The survival time of these patients was affected by the clinical presentation, T, N, stage, and surgical treatment. Ki-67 expression had no impact on survival. An association was found between the parabasal expression of Ki-67 in adjacent non-tumor epithelium and Ki-67 expression in the tumor. Conclusions: Ki-67 lacks prognostic value, probably because it is a marker of the total fraction of proliferating cells, corresponding not only to cells in constant proliferation but also to proliferating cells destined for terminal differentiation.

Keywords: Oral cancer, Ki-67, Prognostic factor