Outcomes of Biopsy Grade Group 1 Prostate Cancer Diagnosis in the Danish Population

BACKGROUND

Debate regarding a nomenclature change for grade group 1 (GG 1) prostate cancer to noncancer has been revived, as this could be a powerful tool in reducing the overtreatment of indolent disease.

OBJECTIVE

To describe outcomes for all men diagnosed with GG 1 prostate cancer in the Danish population, with a focus on men followed conservatively.

DESIGN, SETTING, AND PARTICIPANTS

This was a population-based observational study using data from the Danish Prostate Registry.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We measured the cumulative incidence of curative treatment, endocrine treatment, and cause-specific mortality.

RESULTS AND LIMITATIONS

The cumulative incidence of endocrine therapy at 10 yr was 5.3% (95% confidence interval [CI] 4.3-6.3%) for men with initial active surveillance and 21% (95% CI 19-23%) for men with initial watchful waiting for localized GG 1. In the GG1 cohort, the prostate cancer-specific mortality rate at 15 yr was 14% (95 CI% 11-16%) for men on watchful waiting, 10% (95 CI% 6.7-14%) for men with prostate-specific antigen <10 ng/ml on watchful waiting, and 16% (95 CI% 13-19%) for men who did not receive curative-intent treatment or histological assessment. The study is limited by the historic nature of the observations over a period during which diagnostic procedures and treatments have evolved.

CONCLUSIONS

GG 1 cancer can lead to disease-specific mortality in men with localized prostate cancer, and changing the nomenclature for all men may lead to undertreatment.

PATIENT SUMMARY

Key opinion leaders have suggested that prostate cancers of Gleason grade group 1 (GG 1) should be renamed as noncancer to reduce overtreatment. The argument is that low-grade cancer does not metastasize. However, our nationwide population-based study showed that death from prostate cancer can occur in some men diagnosed with GG 1 disease. These men should be considered in discussions on changing the name for GG 1 prostate cancer.

International Opinions on Grading of Urothelial Carcinoma: A Survey Among European Association of Urology and International Society of Urological Pathology Members

Background

Grade of non-muscle-invasive bladder cancer (NMIBC) is an important prognostic factor for progression. Currently, two World Health Organization (WHO) classification systems (WHO1973, categories: grade 1-3, and WHO2004 categories: papillary urothelial neoplasm of low malignant potential [PUNLMP], low-grade [LG], high-grade [HG] carcinoma) are used.

Objective

To ask the European Association of Urology (EAU) and International Society of Urological Pathology (ISUP) members regarding their current practice and preferences of grading systems.

Design setting and participants

A web-based, anonymous questionnaire with ten questions on grading of NMIBC was created. The members of EAU and ISUP were invited to complete an online survey by the end of 2021. Thirteen experts had previously answered the same questions.

Outcome measurements and statistical analysis

The submitted answers from 214 ISUP members, 191 EAU members, and 13 experts were analyzed.

Results and limitations

Currently, 53% use only the WHO2004 system and 40% use both systems. According to most respondents, PUNLMP is a rare diagnosis with management similar to Ta-LG carcinoma. The majority (72%) would consider reverting back to WHO1973 if grading criteria were more detailed. Separate reporting of WHO1973-G3 within WHO2004-HG would influence clinical decisions for Ta and/or T1 tumors according the majority (55%). Most respondents preferred a two-tier (41%) or a three-tier (41%) grading system. The current WHO2004 grading system is supported by a minority (20%), whereas nearly half (48%) supported a hybrid three- or four-tier grading system composed of both WHO1973 and WHO2004. The survey results of the experts were comparable with ISUP and EAU respondents.

Conclusions

Both the WHO1973 and the WHO2004 grading system are still widely used. Even though opinions on the future of bladder cancer grading were strongly divided, there was limited support for WHO1973 and WHO2004 in their current formats, while the hybrid (three-tier) grading system with LG, HG-G2, and HG-G3 as categories could be considered the most promising alternative.

Patient summary

Grading of non-muscle-invasive bladder cancer (NMIBC) is a matter of ongoing debate and lacks international consensus. We surveyed urologists and pathologists of European Association of Urology and International Society of Urological Pathology on their preferences regarding NMIBC grading to generate a multidisciplinary dialogue. Both the "old" World Health Organization (WHO) 1973 and the "new" WHO2004 grading schemes are still used widely. However, continuation of both the WHO1973 and the WHO2004 system showed limited support, while a hybrid grading system composed of both the WHO1973 and the WHO2004 classification system may be considered a promising alternative.

Increased Body Mass Index Is a Risk Factor for Poor Clinical Outcomes after Radical Prostatectomy in Men with International Society of Urological Pathology Grade Group 1 Prostate Cancer Diagnosed with Systematic Biopsies

INTRODUCTION

The association between obesity and clinically significant prostate cancer (PCa) is still a matter of debate. In this study, we evaluated the effect of body mass index (BMI) on the prediction of pathological unfavorable disease (UD), positive surgical margins (PSMs), and biochemical recurrence (BCR) in patients with clinically localized (≤cT2c) International Society of Urological Pathology (ISUP) grade group 1 PCa at biopsy.

METHODS

427 patients with ISUP grade group 1 PCa who have undergone radical prostatectomy and BMI evaluation were included. The outcome of interest was the presence of UD (defined as ISUP grade group ≥3 and pT ≥3a), PSM, and BCR.

RESULTS

Statistically significant differences resulted in comparing BMI with prostate-specific antigen (PSA) and serum testosterone levels (both p < 0.0001). Patients with UD and PSM had higher BMI values (p < 0.0001 and p = 0.006, respectively). BCR-free survival was significantly decreased in patients with higher BMI values (p < 0.0001). BMI was an independent risk factor for BCR and PSM. Receiver-operating characteristic analysis testing PSA accuracy in different BMI groups, showed that PSA had a reduced predictive value (area under the curve [AUC] = 0.535; 95% confidence interval [CI] = 0.422-0.646), in obese men compared to overweight (AUC = 0.664; 95% CI = 0.598-0.725) and normal weight patients (AUC = 0.721; 95% CI = 0.660-0.777).

CONCLUSION

Our findings show that increased BMI is a significant predictor of UD and PSM at RP in patients with preoperative low-to intermediate-risk diseases, suggesting that BMI evaluation may be useful in a clinical setting to identify patients with favorable preoperative disease characteristics harboring high-risk PCa.

External validation of the Gleason grade group system in Argentinian patients that underwent surgery for prostate cancer

Introduction

The aim of this article was to evaluate the effectiveness of the Gleason grade groups (GGG) system on a group of Argentinian patients with prostate cancer (PC) who underwent radical prostatectomy (RP).

Material and methods

We retrospectively studied 262 patients who underwent RP between 1996 and 2014. To determine the performance and validity of the GGG system, a Kaplan-Meier analysis and multivariate analysis with Cox proportional method were performed to evaluate biochemical recurrence, distance metastases and specific cancer mortality. The area under the curve (AUC) was calculated to compare new groups of degrees of the GGG system with the classical scheme of stratification into 3 groups.

Results

The median follow-up was 84 months. As the groups ascend, there is less confined organ disease (p <0.001) and greater extraprostatic extension (p <0.001), greater invasion of seminal vesicles (p <0.001) and greater lymph node involvement (p <0.001). The biochemical recurrence-free survival at 5 years was 68%, 55%, 22%, 9%, 0% of the 1–5 groups, respectively. Ten-years cancer-specific survival was 96%, 95%, 78%, 64%, 25% for group 1–5, respectively. In the multivariate analysis, the GGG system is presented as the only independent predictor of biochemical recurrence and specific cancer mortality. The AUC indicates that the GGG system has a higher prognostic discrimination compared to the classic 3-group system (6, 7, ≥8).

Conclusions

The International Society of Urological Pathology (ISUP) GGG system is an independent predictor of biochemical recurrence and mortality from prostate cancer in patients treated with RP. The classification into 5 groups shows greater discrimination in the prognosis than the traditional Gleason classification.

Controversial issues in Gleason and International Society of Urological Pathology (ISUP) prostate cancer grading: proposed recommendations for international implementation

The Gleason Grading system has been used for over 50 years to prognosticate and guide the treatment for patients with prostate cancer. At consensus conferences in 2005 and 2014 under the guidance of the International Society of Urological Pathology (ISUP), the system has undergone major modifications to reflect modern diagnostic and therapeutic practices. The 2014 consensus conference yielded recommendations regarding cribriform, mucinous, glomeruloid and intraductal patterns, the most significant of which was the removal of any cribriform pattern from Gleason grade 3. Furthermore, a Gleason score grouping system was endorsed which consisted of five grades where Gleason score 6 (3+3) was classified as grade 1 which better reflected the mostly indolent behaviour of these tumours. Another issue discussed at the meeting and subsequently endorsed was that in Gleason score 7 cases, the percentage pattern 4 should be recorded. This is especially important in situations where modern active surveillance protocols expand to include men with low volume pattern 4. While major progress was made at the conference, several issues were either not resolved or not discussed at all. Most of these items relate to details of assignment of Gleason score and ISUP grade in specific specimen types and grading scenarios. This detailed review looks at the 2014 ISUP conference results and subsequent literature from an international perspective and proposes several recommendations. The specific issues addressed are percentage pattern 4 in Gleason score 7 tumours, percentage patterns 4 and 5 or 4/5 in Gleason score 8-10 disease, minor (≤5%) high grade patterns when either 2 or 3 patterns are present, level of reporting (core, specimen, case), dealing with grade diversity among site (highest and composite scores) and reporting scores in radical prostatectomy specimens with multifocal disease. It is recognised that for many of these issues, a strong evidence base does not exist, and further research studies are required. The proposed recommendations mostly reflect consolidated expert opinion and they are classified as established if there was prior agreement by consensus and provisional if there was no previous agreement or if the item was not discussed at prior consensus conferences. For some items there are reporting options that reflect the local requirements and diverse practice models of the international urological pathology community. The proposed recommendations provide a framework for discussion at future consensus meetings.

Percentage grade 4 tumour predicts outcome for clear cell renal cell carcinoma

Heterogeneity of tumour grading is common in clear cell renal cell carcinoma (ccRCC). WHO/ISUP grading specifies that RCC should be graded based on the highest grade present in at least one high power field. This does not take into account the proportion of high grade tumour present in a cancer, which may itself influence outcome. Cases of ccRCC accessioned by Aquesta Uropathology, Brisbane, Australia, between 2008 and 2015, were reviewed and grading assigned according to WHO/ISUP criteria. For tumours classified as grade 3 (G3) and 4 (G4), the percentage of tumour showing G3 and G4 morphology was assessed for each case. Survival analysis, with time to the development of metastases as the clinical outcome, was performed for six grading subclasses (G3 <10%, G3 10-50%, G3 >50%, G4 <10%, G4 10-50%, G4 >50%). Of the 681 cases of ccRCC in the series, there were 153 cases classified as G3 (91 cases) and G4 (62 cases) for which follow-up was available. During the follow-up period of <1-89 months, 19 (20.9%) patients with G3 and 30 (48.3%) patients with G4 cancers developed metastatic disease. The three subgroups of <10%, 10-50% and >50% G3 tumour were not significant in predicting outcome (p=0.47). Separating G3 into two groups of ≤50% vs >50% was also not significantly associated with outcome (p=0.22). For the three subgroups of G4 ccRCC (<10%, 10-50% and >50% G4) a higher percentage of G4 correlated with time to the development of metastases (p=0.01). Even though G4 tumours as a whole had a significantly worse outcome than G3 tumours (p=0.0004), the difference between G4 <10% and G3 tumours was not significant (p=0.27). On multivariate analysis, that included pT staging category and tumour size, there was a significant difference in survival between G4<10% and G4>50% tumours (p=0.018). The results of the study suggest that for ccRCC, WHO/ISUP G4 category should incorporate the percentage of G4 tumour present.

Grading of renal cell carcinoma

Grading of renal cell carcinoma (RCC) has been recognised as a prognostic factor for almost 100 years. Numerous grading systems have been proposed, initially focusing upon a constellation of cytological features and more recently on nuclear morphology. It has been recommended that grading of RCC should be based upon nucleolar prominence/eosinophilia for grades 1-3, while grade 4 requires nuclear anaplasia (including tumour giant cells, sarcomatoid differentiation and/or rhabdoid morphology). The grading system was adopted formally by the International Society of Urological Pathology (ISUP) and subsequently by the World Health Organisation (WHO), being designated the WHO/ISUP grading classification in the fourth edition of the WHO classification tumours of the urinary system and male genital organs (2016). This grading system has been validated for both clear cell and papillary RCC. Validation studies for chromophobe RCC failed to demonstrate a correlation between grade and outcome for both the superseded Fuhrman grading system and the WHO/ISUP grading classification, and it has been recommended that these tumours not be graded. The WHO/ISUP system has been incorporated into the structured reports of the International Cancer Collaboration on Cancer Reporting for both clear cell and papillary RCC. It is also noted that other types of RCC may be graded, but it must be emphasised in the report that this is for descriptive and diagnostic purposes, and not outcome prediction. More recent studies have shown the incorporation of the presence of tumour necrosis into RCC grading to improve outcome prediction, and this has been validated in several studies.

The accumulation of metabolic syndrome components is associated with higher risk of positive surgical margin among patients with localized prostate cancer after radical prostatectomy

Objective

To evaluate the association between metabolic syndrome (MetS) and the accumulation of its components with prostate cancer (PCa).

Patients and methods

Patients undergoing radical prostatectomy were retrospectively included. Patients were grouped by low risk and intermediate-high risk according to International Society of Urological Pathology grade. Multivariable logistic regression and Cox hazard regression model were utilized to assess the association of MetS with overall survival, biochemical recurrence, upgrading, upstaging, and positive surgical margin (PSM) after prostatectomy. Besides, trend test was also performed to evaluate the impact of the accumulation of MetS components on postoperative pathological feature.

Results

A total of 1,083 patients were eventually enrolled. With a median follow-up of 40.45 months, 197 patients were diagnosed with MetS. No significant association between MetS and survival outcomes and pathological features was found. However, we did notice that the accumulation of the MetS components could lead to an elevated gradient of the PSM risk in the entire cohort (one component: OR=1.46; two components: OR=1.89; ≥3 components: OR=2.07; P for trend=0.0194) and intermediate-high risk group (one component: OR=1.4; two components: OR=1.85; ≥3 components: OR=2.05; P for trend=0.0127).

Conclusion

The accumulation of MetS components could lead to increasing risk of PSM on the entire PCa cohort and patients with intermediate-high risk PCa after prostatectomy, but not for the low-risk patients.

Evolution, controversies and the future of prostate cancer grading

Histological grading of prostate cancer is one of the most important tissue-based parameters for prediction of outcome and treatment response. Gleason grading remains the foundation of prostate cancer grading, but has undergone a series of changes in the past 30 years, often initiated by consensus conference decisions. This review summarizes the most important modifications that were introduced by the 2005 and 2014 International Society of Urological Pathology (ISUP) revisions of Gleason grading and discusses the impact that these have had on current grading practices. A considerable inflation in Gleason scores has been observed, especially following the ISUP 2005 revision, and the effects of this are discussed. ISUP 2014 grading recommendations are described, including the reporting of ISUP grades 1-5. Controversial issues include methods for reporting of grades on needle biopsies, reporting of percent Gleason grades 4/5 and grading of cribriform and intraductal carcinoma of the prostate. Educational programs developed recently to promote standardization of grading are described and their results assessed.

Assessment of tumour-associated necrosis provides prognostic information additional to World Health Organization/International Society of Urological Pathology grading for clear cell renal cell carcinoma

AIMS

The aims of this study were to evaluate the impact of tumour-associated necrosis (TAN) on metastasis-free survival for clear cell renal cell carcinoma (RCC), and to determine whether TAN provides survival information additional to World Health Organization (WHO)/International Society of Urological Pathology (ISUP) grading.

METHODS AND RESULTS

The study consisted of 376 cases of clear cell RCC treated by nephrectomy, for which follow-up was available. WHO/ISUP grade was assigned, and sections were assessed for the presence of TAN. American Joint Committee on Cancer (AJCC) pT staging category and tumour size were also recorded. The development of metastatic disease was taken as the clinical endpoint, and survival analyses, utilising univariate and multivariate models, were performed. WHO/ISUP grades were: grade 1, 35 cases (9.3%); grade 2, 188 cases (50.0%); grade 3, 91 cases (24.2%); and grade 4, 62 cases (16.5%). Staging categories were pT1-pT2 [234 tumours (62.2%)] and pT3-pT4 [139 tumours (37.0%)]. TAN was seen in 128 cases (34.0%). Neither TAN nor metastases were seen in grade 1 tumours. Among grade 2-4 tumours, those with TAN had a significantly worse prognosis than those without TAN (P = 0.017, P = 0.04, and P = 0.006, respectively). Multivariate analysis (WHO/ISUP grade, pT staging category, and TAN) showed all three variables to be independently associated with outcome (P = 0.009, P = 0.005, and P = 0.001, respectively). For all tumour grades and pT staging categories, it was found that the presence of TAN was associated with a 2.91-fold greater risk of metastatic disease.

CONCLUSION

Tumour-associated necrosis is an important prognostic factor for clear cell RCC, independently of WHO/ISUP grade. This supports the suggestion that TAN could be incorporated into tumour grading criteria.

Can Apparent Diffusion Coefficient Values Assist PI-RADS Version 2 DWI Scoring? A Correlation Study Using the PI-RADSv2 and International Society of Urological Pathology Systems

OBJECTIVE

The purposes of this study were to assess correlation of apparent diffusion coefficient (ADC) and normalized ADC (ratio of tumor to nontumor tissue) with the Prostate Imaging Reporting and Data System version 2 (PI-RADSv2) and updated International Society of Urological Pathology (ISUP) categories and to determine how to optimally use ADC metrics for objective assistance in categorizing lesions within PI-RADSv2 guidelines.

MATERIALS AND METHODS

In this retrospective study, 100 patients (median age, 62 years; range, 44-75 years; prostate-specific antigen level, 7.18 ng/mL; range, 1.70-84.56 ng/mL) underwent 3-T multiparametric MRI of the prostate with an endorectal coil. Mean ADC was extracted from ROIs based on subsequent prostatectomy specimens. Histopathologic analysis revealed 172 lesions (113 peripheral, 59 transition zone). Two radiologists blinded to histopathologic outcome assigned PI-RADSv2 categories. Kendall tau was used to correlate ADC metrics with PI-RADSv2 and ISUP categories. ROC curves were used to assess the utility of ADC metrics in differentiating each reader's PI-RADSv2 DWI category 4 or 5 assessment in the whole prostate and by zone.

RESULTS

ADC metrics negatively correlated with ISUP category in the whole prostate (ADC, τ = -0.21, p = 0.0002; normalized ADC, τ = -0.21, p = 0.0001). Moderate negative correlation was found in expert PI-RADSv2 DWI categories (ADC, τ = -0.34; normalized ADC, τ = -0.31; each p < 0.0001) maintained across zones. In the whole prostate, AUCs of ADC and normalized ADC were 87% and 82% for predicting expert PI-RADSv2 DWI category 4 or 5. A derived optimal cutoff ADC less than 1061 and normalized ADC less than 0.65 achieved positive predictive values of 83% and 84% for correct classification of PI-RADSv2 DWI category 4 or 5 by an expert reader. Consistent relations and predictive values were found by an independent novice reader.

CONCLUSION

ADC and normalized ADC inversely correlate with PI-RADSv2 and ISUP categories and can serve as quantitative metrics to assist with assigning PI-RADSv2 DWI category 4 or 5.

Utility of Pathology Imagebase for standardisation of prostate cancer grading

AIMS

Despite efforts to standardise grading of prostate cancer, even among experts there is still a considerable variation in grading practices. In this study we describe the use of Pathology Imagebase, a novel reference image library, for setting an international standard in prostate cancer grading.

METHODS AND RESULTS

The International Society of Urological Pathology (ISUP) recently launched a reference image database supervised by experts. A panel of 24 international experts in prostate pathology reviewed independently microphotographs of 90 cases of prostate needle biopsies with cancer. A linear weighted kappa of 0.67 (95% confidence interval = 0.62-0.72) and consensus was reached in 50 cases. The interobserver weighted kappa varied from 0.48 to 0.89. The highest level of agreement was seen for Gleason score (GS) 3 + 3 = 6 (ISUP grade 1), while higher grades and particularly GS 4 + 3 = 7 (ISUP grade 3) showed considerable disagreement. Once a two-thirds majority was reached, images were moved automatically into a public database available for all ISUP members at www.isupweb.org. Non-members are able to access a limited number of cases.

CONCLUSIONS

It is anticipated that the database will assist pathologists to calibrate their grading and, hence, decrease interobserver variability. It will also help to identify instances where definitions of grades need to be clarified.

Clear cell renal cell carcinoma: validation of World Health Organization/International Society of Urological Pathology grading

AIMS

In 2012, the International Society of Urological Pathology (ISUP) introduced a novel grading system for clear cell renal cell carcinoma (ccRCC) and papillary renal cell carcinoma. This system is incorporated into the latest World Health Organization renal tumour classification, being designated WHO/ISUP grading. This study was undertaken to compare WHO/ISUP and Fuhrman grading and to validate WHO/ISUP grading as a prognostic parameter in a series of clear cell RCC.

METHODS AND RESULTS

Analysis of 681 cases of ccRCC showed that 144 tumours could not be assigned a Fuhrman grade on the basis of ambiguous grading features. The application of WHO/ISUP grading resulted in a general down-grading of cases when compared with Fuhrman grading. In a sub-group of 374 cases, for which outcome data were available, 9.3% were WHO/ISUP grade 1, 50.3% were grade 2, 24.1% grade 3 and 16.3% grade 4, while the distribution of Fuhrman grades was 0.4% grade 1, 48.7% grade 2, 29.4% grade 3 and 21.5% grade 4. There were no recurrence/metastases amongst patients with WHO/ISUP grade 1 tumours and there was a significant difference in outcome for WHO/ISUP grades 2, 3 and 4. For Fuhrman grading the cancer-free survival was not significantly different for grade 2 and grade 3 tumours. On multivariate analysis WHO/ISUP grade and pT staging category were found to retain prognostic significance.

CONCLUSIONS

The study demonstrates that FG cannot be applied in >20% of cases of ccRCC and the WHO/ISUP provides superior prognostic information.

From Gleason to International Society of Urological Pathology (ISUP) grading of prostate cancer

Gleason grading of prostate cancer has gained worldwide acceptance since its introduction 50 years ago. This system has fulfilled the role of a powerful prognostic indicator for many years and this has influenced treatment. There have been numerous changes to the management and diagnosis of prostate cancer since 1966, including prostate-specific antigen screening, resulting in the early detection of prostate cancer, This has resulted in the evolution of Gleason grading with the informal adoption of a number of alterations. Significant changes to Gleason grading were made in 2005 through a consensus conference convened by the International Society of Urological Pathology (ISUP). In more recent times, the necessity for further changes to prostate cancer grading has been apparent and a follow-up ISUP consensus conference was held in 2014. Changes resulting from this conference included the classifying of all cribriform cancer and glomeruloid patterns as Gleason grade 4, the grading of mucinous adenocarcinoma based on underlying architecture rather than uniformly considering these tumors as pattern 4, and the introduction of a Gleason score (GS)-based 5 grade system, which incorporated the 2014 modifications to the Gleason grading system. Designated ISUP grade, this system consists of five grades: grade 1 (GS ≤3 + 3), grade 2 (GS 3 + 4), grade 3 (GS 4 + 3), grade 4 (GS 4 + 4, 3 + 5, 5 + 3) and grade 5 (GS 9-10). With further advances recently reported in the literature, it is apparent that amendments to the current system are likely to be necessary in the future.

Prognostic value of pathological features of primary lesion in metastatic renal cell carcinoma treated with sorafenib

AIM

This study aimed to investigate whether the pathological features of primary lesions show additional prognostic value in patients with metastatic renal cell carcinoma who are treated with sorafenib.

PATIENTS & METHODS

A consecutive cohort of 284 patients was included from Fudan University Shanghai Cancer Center between 2007 and 2013. The association between survival and pathological features of primary tumors was assessed using the Cox proportional hazards model. The incremental value of prognostication was evaluated.

RESULTS

We found that the pathological features of primary lesions provided added prognostic value over the Memorial Sloan-Kettering Cancer Center model in patients with metastatic renal cell carcinoma who were treated with sorafenib.

CONCLUSION

Addition of a pathological score in the clinical setting could better identify patients at risk of poor survival.

Gleason and Fuhrman no longer make the grade

Grading is an important prognostic parameter for prostate adenocarcinoma and renal cell carcinoma (RCC); however, the most frequently used classifications fail to account for advances in our understanding of the diagnostic features, classification and/or behaviour of these tumours. In 2005 and 2014, the International Society of Urological Pathology (ISUP) proposed changes to Gleason scoring with the adoption of the ISUP grading for prostate cancer in 2014 (grade 1, score 3 + 3; grade 2, score 3 + 4; grade 3, score 4 + 3; grade 4, score 8; grade 5, score 9-10). Internationally the Fuhrman grading system is widely employed despite criticisms related to its application, validity, and reproducibility. In 2012, the ISUP established a grading system for RCC (grade 1, the nucleolus is not seen or is inconspicuous and basophilic at ×400 magnification; grade 2, nucleoli are eosinophilic and clearly visible at ×400 magnification; grade 3, nucleoli are clearly visible at ×100 magnification; grade 4, tumours show extreme pleomorphism or rhabdoid and/or sarcomatoid morphology). This grading has been validated for clear cell RCC and papillary RCC. It was further recommended that chromophobe RCC not be graded. For other morphotypes of RCC, ISUP grading has not been validated as a prognostic parameter, but can be used for descriptive purposes.