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ORIGINAL ARTICLE |
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Year : 2013 | Volume
: 3
| Issue : 2 | Page : 132-136 |
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Gleason's grading in Tru-Cut biopsy specimens of prostate carcinoma
Manjit Singh Bal1, Parul Kansal1, Harjinder Singh2, Navneet Kaur1, Pankaj K Garg2
1 Department of Pathology, Government Medical College and Rajindra Hospital, Patiala, Punjab, India 2 Department of Urology and Surgery, Government Medical College and Rajindra Hospital, Patiala, Punjab, India
Date of Web Publication | 13-Dec-2013 |
Correspondence Address: Pankaj K Garg Department of Urology and Surgery, Government Medical College and Rajindra Hospital, Patiala-147 001, Punjab India
Source of Support: None, Conflict of Interest: None | Check |
DOI: 10.4103/2278-9596.122934
Background: Prostate cancer is an important growing health problem presenting a challenge to urologists, radiologists, pathologists, and oncologists. Many men have incidental microscopic foci of prostate cancer at postmortem that did not manifest during life time. However, some cancers are aggressive with a rapidly worsening course. The objective of this study was to diagnose prostate carcinoma in Tru-Cut biopsy specimens, determine Gleason's grading and correlate clinicopathological findings and prostate specific antigen (PSA) level. Materials and Methods: Tru-Cut biopsies were performed on 100 clinically highly suspicious patients of prostate carcinoma. Eight to 10 cores of prostatic tissue were obtained. The samples were formalin-fixed and paraffin-embedded. The prostatic tumors were diagnosed and assigned Gleason scores using hematoxylin and eosin (H and E) stained sections. Results: Microscopic examination revealed adenocarcinoma in 59, benign prostatic hyperplasia (BPH) in 35, and inadequate biopsy in five cases. The age distribution of these 59 cases with adenocarcinoma revealed that 28 were in the 8 th decade, followed by 7 th , 6 th , and 9 th decades, respectively. The mean age was 68.20 years. The Gleason score was 5-7 in 37 patients, 2-4 in 14 cases, and 8-10 in eight cases. The highest PSA level was in Gleason's score of 8-10. Thus, the PSA levels are more in patients with high Gleason grade. Conclusion: Adenocarcinoma is the most common type of prostate carcinoma. The majority of patients had a Gleason score of 5-7, followed by 2-4, and 8-10. The more anaplastic type of cancers were present in the least number of cases. Keywords: BPH, gleason score, prostate carcinoma, tru-cut biopsy
How to cite this article: Bal MS, Kansal P, Singh H, Kaur N, Garg PK. Gleason's grading in Tru-Cut biopsy specimens of prostate carcinoma. Arch Int Surg 2013;3:132-6 |
Introduction | | |
Prostate carcinoma is predominantly a disease of elderly men with more than 75% of new cases being diagnosed in men older than 65 years. [1] Approximately, 95-98% of prostate cancers are adenocarcinomas developing in acini of prostatic ducts. Both early and advanced cancers of prostate consist of well or poorly formed small, medium or large acini and tubules. Glandular elements may be closely packed together with little intervening stroma and grouped in a nodular or linear arrangement. [2] Malignant acini usually consist of a single row of cuboidal or columnar cells and nearly always lack a basal layer of cells, even when the glandular elements seem to consist of more than one row of cells. Disturbances of architecture, invasion, and anaplasia are the important histopathologic criteria for the diagnosis of prostate cancer. [2] Donald F. Gleason developed a grading system from 1960 to 1974 while reviewing an accumulated number of about 5,000 prostate cancer patients in prospective randomized clinical trials at the Veterans Administration Cooperative Urological Research Group (VACURG). [3],[4],[5],[6]
The Gleason system is based on the glandular pattern of the tumor as identified at relatively low magnification. Cytologic features play no role in the grade of the tumor. Both the primary (predominant) and the secondary (second most prevalent) architectural patterns are identified and assigned a grade from 1 to 5, with 1 being the most differentiated and 5 being the least differentiated. Because both the primary and the secondary patterns are influential in predicting prognosis, there resulted a Gleason sum or score obtained by the addition of the primary and secondary grades. If a tumor has only one histologic pattern, then for uniformity, the primary and secondary patterns are given the same grade. Gleason scores range from 2 (1 + 1 = 2), which represents tumors uniformly composed of Gleason pattern 1 tumor, to 10 (5 + 5 = 10), which represents totally undifferentiated tumors. Unfortunately, the intermediate (5-7) Gleason score tumors are highly unpredictable in their clinical aggressiveness. [7] This limitation is of particular importance as the majority of tumors (76%) fall into this intermediate category. [8] Thus predicting the biological potential of the majority of prostate cancer based upon histology alone is problematic. However, grading in the form of Gleason's scoring system is an important factor in determining the prognosis. Patients with low Gleason's score live longer and few die of prostate cancer. [7],[9]
In the present study, we used Gleason's grading system [Table 1] to diagnose prostate carcinoma cases in Tru-Cut biopsy specimens of prostate and to correlate Gleason scores and pretreatment prostate specific antigen (PSA) levels in patients with prostate cancer.
Materials and Methods | | |
This prospective study was carried out in the urology department of our institution. After clinical evaluation and informed consent, digital rectal examination was done and the hard and most suspicious area of the prostate was found and Tru-Cut needle was inserted to take 8-10 cores of prostatic tissue. Antibiotics were given for 5 days. The sample was put in 10% formalin in a sterile container. The biopsy material in each case was grossly examined and description noted. The material was processed as a routine in an automatic tissue processor. Two paraffin sections were prepared in each case and stained with hematoxylin and eosin (H and E) stain. After that, smears were examined microscopically. Serial and thin sections were done wherever required. PSA was assessed before prostatic biopsy and was correlated with the Gleeson score for each patient.
Results | | |
The maximum cases were diagnosed as adenocarcinoma. Only about 5% of the biopsies were inadequate because of small size of biopsy specimen [Table 2]. | Table 2: Distribution of lesions of prostate on Tru-Cut biopsy in 100 patients
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The maximum number of patients was in the 8 th decade followed by 7 th , 6 th , 9 th , and 4 th decades. Mean age was 69.9 years ± 9.3 standard deviation (SD; coefficient of variance 13.58%) [Table 3].
Of these 100 patients with clinically suspicious carcinoma of the prostate, there were 59 cases of carcinoma [Table 2]. The histological diagnosis in all cases was adenocarcinoma. [Table 4] describes the age distribution of these 59 cases of adenocarcinoma. Twenty-eight were in the 8 th decade, followed by 7 th , 6 th , and 9 th decades. The youngest patient with adenocarcinoma was 55-year-old and the eldest was 88-year-old. The mean age was 68.20 ± 7.14 (coefficient of variation is 10.26%) [Table 4].
Gleason score in all the cases were recorded according to Gleason scoring system given by Donald F. Gleason (1960-1974). [3],[4],[5],[6] The observations show Gleason score 5-7 in, 37 patients (62.71%). The next score was 2-4 in 14 cases (23.72%) and in eight cases (13.55%) the grade was 8-10. The more anaplastic type of cancers was present in the least number of cases [Table 5]. | Table 5: Frequency distribution of Gleason's score in adenocarcinoma cases
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Pretreatment PSA levels were available in 53 out of 59 patients with carcinoma of the prostate. The average PSA level in Gleason grade 2-4 was 32.13 ng/ml, 5-7 was 31.06 ng/ml, and 8-10 was 44 ng/ml. The highest PSA level was in Gleason's score of 8-10. Thus, the PSA levels are more in patients with high Gleason's grade. Gleason grade corresponds with average PSA levels in eight cases. However, in 33 cases with Gleason score of 5-7, the average PSA levels remained slightly less than for 12 patients with Gleason score of 2-4 in whom average PSA levels remained 32.13 [Table 6] Perineural invasion was seen in six patients out of a total 59 patients who had prostate carcinoma. Among these, four (50%) patients had a Gleason score of 8-10 and two (5.4%) had a Gleason score of 5-7. Thus, perineural invasion was more common in patients with a high Gleason score. | Table 6: Correlation between Gleason's score and pretreatment prostate specifi c antigen (PSA) levels
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Discussion | | |
The precise worldwide prevalence of prostate carcinoma is difficult to estimate because of lack of complete statistical data, but according to the World Health Organization there were 679,023 new cases and 221,002 deaths from prostate carcinoma worldwide in 2002. [10] Prostate carcinoma is also a considerable public health problem in developing countries. According to National Cancer Registry Program, the age adjusted rates of prostate cancer/100,000 in India in the year 2003 are: Mumbai-7.2, Bangalore-6.8, Chennai-3.9, Delhi-8.2, and Bhopal-5.9. [11] In the current study, out of 100 patients, 59% were diagnosed as adenocarcinoma followed by BPH in 35%.
Age is the most significant risk factor. In this study, the mean age of diagnosis was 68.2 years and 91.52% of the patients were diagnosed after the age of 60. Below the age of 50, prostate carcinoma is rarely diagnosed though an increased incidence in younger men has been observed lately. [12],[13] In the current study also, none of the patient was below 50 years [Table 4]. In a study by Sakr and Haas, [14] prostatic intraepithelial neoplasia was identified in 0, 9, 20, and 44%; and small foci of histological cancer in 0, 0, 27, and 34% of the male patients in the 2 nd , 3 rd , 4 th , and 5 th decades of age, respectively. The majority of the cases of prostatic intraepithelial neoplasia were of low grade. It was suggested that most men would get prostate carcinoma if they lived long enough. These findings confirm that prostate cancer is a disease of elderly men although young men are not exempted.
The first noninvasive steps to detect prostate cancer are the digital rectal examination (DRE) and a prostate-specific antigen testing. It is more difficult to detect cancer with digital rectal examination than with PSA. [15] In the present study of 100 patients, based on clinical history, abnormal digital rectal examination findings and raised PSA, a clinical suspicion of carcinoma was made. Tru-Cut biopsy was performed in these patients. In this study, PSA levels were available in 53 out of 59 patients of carcinoma prostate. The average PSA levels in Gleason grade 2-4 was 32.13 ng/ml, 5-7 was 31.06 ng/ml, and 8-10 was 44 ng/ml. The highest PSA level was in Gleason score of 8-10. Thus, the PSA levels are more in patients with high Gleason's grade. Gleason grade corresponds with average PSA levels in eight cases. However, in 33 cases with Gleason score of 5-7, the average PSA levels remained slightly less than for 12 patients with Gleason score of 2-4 in whom average PSA levels remained 32.13. In a study by Mawakyoma and Mabandi, [16] PSA levels correlated well with Gleason scores in all the patients; but in our study, PSA levels correlated with Gleason scores in some of the patients only. This can be attributed to nonavailability of PSA values in all patients. [16]
Adenocarcinoma was the predominant histological type in our study as it represented 100% of histological types. This finding is in agreement with the study by Thompson, et al., in 2004. [17] According to Draisma and Postma. [18] the Gleason score is probably the single most powerful predictor of patient outcome, which correlates with multiple other parameters related to prognosis, such as age, serum PSA, [19] clinical stage, [20] and pathological stage. [6] Numerous studies show that the Gleason grading is an independent and very powerful prognostic factor, both for prediction of the natural history of prostate cancer [21],[22],[23] and for assessment of the risk of recurrence after radical prostatectomy. [24] Regarding Gleason score in this study, 62.71% patient were found to have a Gleason score of 5-7 and 13.55% presented with a high Gleason's score (8-10). Comparing these findings with the study done by Catalona et al., [25] the histological findings indicated that their patients had more aggressive disease than patients in our region. In their study, 60% of patients showed cancer of high histological grade (Gleason's score 8-10) compared to 13.55% in our patients, and there were no patients with low grade (Gleason's score 2-4) adenocarcinoma in their series. Genetic, environmental, racial, and dietary factors may be possible explanations for this difference.
A weakness of the Gleason system is that it has a pronounced clustering in the mid-range of the scores. Some reports of radical prostatectomy series observed as many as 86-89% of the tumors presenting a Gleason score 6 or 7, [26],[27] which corresponds to the present study in which 37 (62.71%) had a Gleason score between 5 and 7. Gleason pattern 1 is extremely rare. None of the patients in this study had a Gleason score of 1. Pattern 2 is usually mixed with some pattern 3 resulting in a Gleason score 5. As a result, Gleason score 2, 3, and 4 are only exceptionally assigned and it is recommended not to use scores 2-4 on needle biopsies. [28] Pattern 5 is usually mixed with some pattern 4 resulting in a Gleason score 9, and therefore Gleason score 10 is uncommon as in this study in which only eight (13.55%) had a Gleason score of 8, while none of the patients had a Gleason score of 9 or 10.
Conclusions | | |
The present study described the gross and microscopic examination of 100 Tru-Cut needle biopsies of prostate in clinically highly suspicious cases on the basis of abnormal digital rectal examination and raised PSA. Prostate carcinoma was diagnosed in elderly patients. Digitally guided Tru-Cut biopsy of the prostate if carried out properly is reliable and was able to established diagnosis in about 95% of our patients. Majority of our patients had low Gleason's score which correlated with low PSA levels. Finally, perineural invasion was more common in patients with a high Gleason score.
References | | |
1. | Rosai J, Ackerman. Rosai and Ackerman's Surgical Pathology. 10 th ed., Vol 1. New Delhi: Elsevier; 2011. p. 1295-306. |
2. | Sata F, Umenura T, Kishi R. The epidemiology of prostate cancer-recent trends in prostate cancer incidence and mortality. Gan To Kagaku Rhyoho 2001;28:184-8. |
3. | Bailar JC 3rd, Mellinger GT, Gleason DF. Survival rates of patients with prostatic cancer, tumor stage, and differentiation - preliminary report. Cancer Chemother Rep 1966;50:129-36. [PUBMED] |
4. | Gleason DF. Classification of prostatic carcinomas. Cancer Chemother Rep 1966;50:125-8. [PUBMED] |
5. | Mellinger GT, Gleason D, Bailar JC 3rd. The histology and prognosis of prostatic cancer. J Urol 1967;97:331-7. |
6. | Gleason DF. Histologic grading of prostate cancer: A perspective. Hum Pathol 1992;23:273-9. [PUBMED] |
7. | Egevad L, Granfors T, Karlberg L, Bergh A, Stattin P. Prognostic value of the Gleasons score in prostate cancer. BJU Int 2002;89:538-42. [PUBMED] |
8. | Shirley SE, Escoffery CT, Sargeant LA, Tulloch T. Clinical pathological features of prostate cancer in Jamaica men. BJU Int 2002;89:390-5. [PUBMED] |
9. | Carter HB, Coffey DS. The Prostate: An increasing medical problem. Prostate 1990;16:39-48. [PUBMED] |
10. | Ferlay J. GLOBOCAN 2002: Cancer incidence, mortality and prevalence world wide. IARC Cancer base No. 5 version 2.0. Lyon: IARC Press; 2004. |
11. | Yeole BB. Trends in prostate cancer incidence in India. Asian Pac J Cancer Prev 2008;9:141-4. [PUBMED] |
12. | Merrill RM, Lyon JL. Explaining the difference in prostate cancer mortality rates between white and black men in the United States. Urology 2000;55:730-5. [PUBMED] |
13. | Gronberg H. Prostate cancer epidemiology. Lancet 2003;361:859-64. |
14. | Sakr WA, Haas GP, Cassin BF, Pontes JE, Crissman JD. The frequency of carcinoma and intraepithelial neoplasia of the prostate in young male patients. J Urol 1993;150:379-85. [PUBMED] |
15. | Harris R, Lohr KN. Screening for prostate cancer: An update of the evidence for the U.S. Preventive Services Task Force. Ann Intern Med 2002;137:917-29. |
16. | Mawakyoma HA, Mabandi JL. Prostate cancer; Correlation of Gleason's score and pretreatment prostate specific antigen in patients. Prof Med J Jun 2010;17:235-40. |
17. | Thompson IM, Pauler DK, Goodmann PJ, Tangen CM, Lucia MS, Parnes HL, et al. Prevalence of prostate cancer among men with a prostate-specific antigen level < or = 4.0ng per milliter. J Med 2004;350:2239-46. |
18. | Draisma G, Postma R, Schröder FH, van der Kwast TH, de Koning HJ. Gleason score, age and screening: Modeling dedifferentiation in prostate cancer. Int J Cancer 2006;119:2366-71. |
19. | Horninger W, Rogatsch H, Reissigl A, Volgger H, Klocker H, Hobisch A, et al. Correlation between preoperative predictors and pathologic features in radical prostatectomy specimens in PSA-based screening. Prostate 1999;40:56-61. [PUBMED] |
20. | Albertsen PC, Fryback DG, Storer BE, Kolon TF, Fine J. Long-term survival among men with conservatively treated localized prostate cancer. JAMA 1995;274:626-31. [PUBMED] |
21. | Pan CC, Potter SR, Partin AW, Epstein JI. The prognostic significance of tertiary Gleason patterns of higher grade in radical prostatectomy specimens: A proposal to modify the Gleason grading system. Am J Surg Pathol 2000;24:563-9. [PUBMED] |
22. | Andren O, Fall K, Franzén L, Andersson SO, Johansson JE, Rubin MA, et al. How well does the Gleason score predict prostate cancer death? A 20-year followup of a population based cohort in Sweden. J Urol 2006;175:1337-40. |
23. | Epstein JI, Partin AW, Sauvageot J, Walsh PC. Prediction of progression following radical prostatectomy. A multivariate analysis of 721 men with long-term follow-up. Am J Surg Pathol 1996;20:286-92. [PUBMED] |
24. | Humphrey PA. Gleason grading and prognostic factors in carcinoma of the prostate. Mod Pathol 2004;17:292-306. [PUBMED] |
25. | Steinberg DM, Sauvageot J, Piantadosi S, Epstein JI. Correlation of prostate needle biopsy and radical prostatectomy Gleason grade in academic and community settings. Am J Surg Pathol 1997;21:566-76. [PUBMED] |
26. | Stamey TA, McNeal JE, Yemoto CM, Sigal BM, Johnstone IM. Biological determinants of cancer progression in men with prostate cancer. JAMA 1999;281:1395-400. [PUBMED] |
27. | Bastacky SI, Walsh PC, Epstein JI. Relationship between perineural tumor invasion on needle biopsy and radical prostatectomy capsular penetration in clinical stage B adenocarcinoma of the prostate. Am J Surg Pathol 1993;17:336-41. [PUBMED] |
28. | Catalona WJ, Southwick PC, Slawin KM, Partin AW, Brawer MK, Flanigan RC, et al. Comparison of percent free PSA, PSA density and age-specific PSA cut offs for prostate cancer detection and staging. Urology 2000;56:255-60. [PUBMED] |
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6]
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