Title: Stratification of Ki 67 proliferation marker labelling index – Use in Gleason Score Grading of Prostatic Carcinoma

Authors: Dr Nimmy Cyriac, Dr C.F. Mathew

 DOI: https://dx.doi.org/10.18535/jmscr/v7i3.226

Abstract

Introduction: Prostatic carcinoma is a common cause of morbidity and mortality in men worldwide. Gleason score is the most accepted method of grading Prostatic carcinoma. At times it is difficult to determine Gleason score which is partially subjective. Ki -67 expression in Prostatic carcinoma has shown correlation with Gleason score. This study is designed to evaluate whether the Ki-67 proliferation marker labelling index can be useful in determining the grade of Prostatic carcinoma using routine histology as gold standard.

Methods: 54 cases of adenocarcinoma prostate having adequate tissue available for immunohistochem-istry was included in the study. 4 micrometer thick sections were obtained for H&E and immunohistochemical staining with MIB 1 – following antigen retrieval.

Results: All the prostatic carcinoma cases studied are acinar adenocarcinomas. The most common age group is between 61-70 years.  Majority of patients have a Gleason score of 7 (40.7%) and grade group 5 (37%). The mean Ki67 labelling index in low grade tumours is 17.3% and in high grade tumours is 55.1%. Ki67 LI in low grade tumours is between 0-30% and in high grade tumours is >30% and thus a value of 30% is used as a cut off to discriminate the two.

Conclusion: The findings of the study indicate that Ki67 labelling of needle biopsy of prostate can be used as an additional diagnostic parameter for differentiating between low and high grade prostatic carcinoma. This may be useful in the clinical management of these patients. It could help in determining the subset of patients having favourable prognosis and also identify those who  might benefit from Active surveillance.

Keywords: Gleason score (GS); Ki67labelling index (Ki67LI); Prostatic carcinoma; grading.

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Corresponding Author

Dr Nimmy Cyriac

Analil House, Uzhavoor P.O., Kottayam District, Kerala – 686634, India

Phone- 9495351076, Email: This email address is being protected from spambots. You need JavaScript enabled to view it.