Reporting of Prostatic Adenocarcinoma in Needle Biopsies-Gleason's Grading vs Contemporary Group Grading System: Single Centre Experience

Vinay KS, Siddappa S
2018 Clinical Research Open Access  
Gleason grading system which is used for reporting prostatic adenocarcinoma is an important grading parameter for prognostication and helps in making treatment decisions. Needle biopsy Gleason score correlates well with the final score of majority of radical prostatectomy specimens and even with the serum prostate specific antigen levels. Gleason grading system has evolved from the original scheme summarized by Dr. Donald Gleason in 1970 to a significantly modified system after two major
more » ... us meetings conducted by ISUP in 2005 and 2014. Original scheme and latest modifications of Gleason grading system which still has some major limitations has led to a new 'Contemporary Grade Group system' proposed by 2014 ISUP which in turn adopted by the 2016 WHO classification of tumors of prostate. Objective: An observational study to compare traditional Gleason's grading system with contemporary grade grouping system in reporting prostate core biopsies Materials and Methods: A study of prostatic core biopsies from August 2016 to July 2017 (One year study period) received in the department of pathology, Institute of NephroUrology, Victoria hospital campus, Bangalore, Karnataka, India were included. Biopsies of patients after treatment for prostatic carcinoma and biopsies which did not include any glandular component were not included. Core biopsies (6 cores from each case) were received in 10% formalin. All the cores were embedded and sections were cut at 3 to 5 microns. Hematoxylin and eosin staining was done and examined by pathologists. Individual cores from each case were screened and reported independently following both 'Gleason grading system' as well as 'Contemporary grade grouping system'. Highest Gleason score/Group grade was mentioned in the final impression. Results: We received a total number of 46 biopsy samples during the study period. Out of 46, Seventeen were reported as prostatic adenocarcinoma, 2 were atypical small acinar proliferation (ASAP), 2 were high grade prostatic intraepithelial neoplasia (HGPIN) and the rest were benign prostatic tissue. 17 prostatic adenocarcinoma cases were further classified by both Gleason's / Contemporary grade group system as follows, 2 cases (11. 76%) -Grade group I [GS 3+3=6/10], 2 cases (11. 76%) -Grade group II [3+4=7], 7 cases (41. 17%) -Grade group III [ GS 4+3=7/10], 4 cases (23. 52%) -Grade group IV [GS 4+4=10], 2 cases(11. 76%) -Grade group V [ GS 5+4=9/10]. Perineural invasion was seen in 12 out of 17 cases (70. 55%). Average PSA levels were 37. 35 ng/dL. Lymphovascular emboli were not seen in any of the cases. Conclusion: Gleason system for prostatic cancer is an important and universally (WHO endorsed) used prognostic grading system. It has stood the test of time for more than 4-5 decades. Although modification has been done over the time by consensus conferences, it has got some major limitations. To overcome these limitations, a new contemporary Grade grouping system has been proposed recently. The new Contemporary grade grouping system has simplified 5 grades with lowest possible grade of 1 with more accurate grade stratification. The new grading system has been accepted by the 2016 WHO. As a pathologist's point of view, reporting of prostate core biopsies based on glandular architecture at low power examination gives better information about the grades. Since we are accustomed to the traditional GS, we should report the Gleason score and also simultaneously concur with the grade of CGGS. We recommend reporting of the prostate biopsies by following both the contemporary grade grouping system along with the traditional Gleason system till it becomes widely accepted and practiced. New grade grouping system is simpler and more precisely represent the prognostication of prostate cancer biology. It is also endorsed by the WHO.
doi:10.16966/2469-6714.133 fatcat:27ubd7dar5d2zn73z22etyjy6e