Microscopic bladder neck involvement by prostate carcinoma in radical prostatectomy specimens is not a significant independent prognostic factor

Aberrant expression of GATA3 in metastatic adenocarcinoma of the prostate: an important pitfall

AIMS

The distinction of high-grade prostate cancer (PCa) from poorly differentiated urothelial carcinoma (UC) can be somewhat challenging on clinical and morphological grounds alone, yet it is of great importance for prognostication and choice of treatment. GATA3 is a useful immunohistochemical marker to confirm urothelial origin. However, recent works report strong GATA3 immunoexpression in primary high-grade PCa. The aim of this study was to explore GATA3 expression specifically in metastatic PCa.

METHODS AND RESULTS

The pathology databases of four tertiary institutions were queried for cases of metastatic PCa. Available slides and clinical records were reviewed by experienced genitourinary pathologists. Prostatic markers (PSA, PSAP, NKX3.1) and GATA3 immunohistochemistry were performed. A total of 163 metastatic PCa cases were included. At least one prostate marker was positive in each case of non-regional distant metastasis, confirming prostatic origin. GATA3 strong staining was found in four (2.5%) cases: two liver, one bone and one non-regional lymph-node metastases. All four patients had Grade Group 5 PCa at the initial diagnosis. The metastatic prostatic adenocarcinomas were solid, either with no gland formation (n = 3) or with only focal cribriforming (n = 1).

CONCLUSIONS

To our knowledge, this is the first study exploring GATA3 expression specifically in metastatic PCa. Despite being infrequent, GATA3 positivity in high-grade PCa may lead to misdiagnosis, with clinical implications. We recommend a panel of immunohistochemical markers, both prostatic and urothelial, for ruling out UC, either in primary tumour samples or in the event of metastases of unknown primary, when a genitourinary origin is suspected.

Grossing and reporting of radical prostatectomy specimens: An evidence-based approach

Radical prostatectomy (RP) constitutes the primary treatment option for patients with clinically localized, biopsy-proven prostate cancer that requires local treatment with curative intent. Accurate reporting of radical prostatectomy specimens is required to guide further risk stratification and management of patients. Hence, for the handling and reporting of RP specimens, a standardized protocol should be followed. Many general pathologists may not be well-versed with the guidelines for the handling of radical prostatectomy specimens. This article discusses a detailed approach to grossing techniques, including specimen description, fixation requirements, gross cut-up, and reporting of the grade and stage of RP specimens. This will enable the pathologist to aid in multidisciplinary management.

The Clinical Significance of Either Extraprostatic Extension or Microscopic Bladder Neck Invasion Alone Versus Both in Men With pT3a Prostate Cancer Undergoing Radical Prostatectomy: A Proposal for a New pT3a Subclassification

The prognosis of prostate cancers exhibiting extraprostatic extension [other than bladder or seminal vesicle invasion (EPE)] and/or microscopic bladder neck invasion (mBNI) is variable, and further risk stratification is required. We herein assessed radical prostatectomy findings and long-term oncologic outcomes in consecutive 957 patients with pT3a disease. The patient cohort was divided into 4 groups, focal EPE (F-EPE) only (n=177; 18.5%), nonfocal/established (E-EPE) only (n=634; 66.2%), mBNI only (n=51; 5.3%). The rate of positive surgical margin and estimated volume of tumor were significantly higher in patients with both EPE and mBNI than in those with either. In addition, compared with F-EPE or mBNI only, E-EPE only was significantly associated with higher Grade Group, lymph node metastasis, and larger tumor volume. Kaplan-Meier analysis revealed a comparable prognosis after prostatectomy between those showing F-EPE only versus mBNI only ( P =0.986), and these 2 cohorts were combined for further analysis. Then, patients showing E-EPE only had a significantly higher or lower risk of progression compared with those showing F-EPE or mBNI only ( P <0.001) or both EPE and mBNI ( P <0.001), respectively. These significant differences in progression-free survival were also seen in subgroups, including those with or without undergoing adjuvant therapy before recurrence and those showing no lymph node metastasis. In multivariate analysis, F-EPE or mBNI only (hazard ratio=0.524, P =0.003) or both EPE and mBNI (hazard ratio=1.465, P =0.039) (vs. E-EPE only) showed significance for progression. Based on these findings, we propose a novel pT3a subclassification, pT3a1 (F-EPE or mBNI alone), pT3a2 (E-EPE alone), and pT3a3 (both EPE and mBNI).

Evolution in Prostate Cancer Staging: Pathology Updates From AJCC 8th Edition and Opportunities That Remain

The Tumor-Nodes-Metastasis system at the core of prognostic staging has been recently updated in the American Joint Committee on Cancer (AJCC) 8th edition, published in 2016. For prostate cancer, significant changes in staging of organ-confined disease, inclusion of a new grade grouping, and provision of levels of evidence for these modifications are part of what differentiates the 8th edition AJCC from prior iterations. Herein, the rationale underlying these changes is detailed. In addition, data elements not well represented in the present system are highlighted as opportunities for fresh study that may impact future AJCC classifications.

Prostate cancer reporting and staging: needle biopsy and radical prostatectomy specimens

Prostatic adenocarcinoma remains the most common cancer affecting men. A substantial majority of patients have the diagnosis made on thin needle biopsies, most often in the absence of a palpable abnormality. Treatment choices ranging from surveillance to radical prostatectomy or radiation therapy are largely driven by the pathologic findings in the biopsy specimen. The first part of this review focuses on important morphologic parameters in needle biopsy specimens that are not covered in the accompanying articles. This includes tumor quantification as well as other parameters such a extraprostatic extension, seminal vesicle invasion, perineural invasion, and lymphovascular invasion. For those men who undergo radical prostatectomy, pathologic stage and other parameters are critical in prognostication and in determining the appropriateness of adjuvant therapy. Staging parameters, including extraprostatic extension, seminal vesicle invasion, and lymph node status are discussed here. Surgical margin status is also an important parameter and definitions and reporting of this feature are detailed. Throughout the article the current reporting guidelines published by the College of American Pathologists and the International Collaboration on Cancer Reporting are highlighted.

Prediction of bladder neck invasion and tumor extension to bladder neck margin by prostatic adenocarcinoma: a nomogram using biopsy data including transition zone tumor morphology

Transition zone (TZ) prostatic adenocarcinoma can be identified on needle core biopsy based on tumor morphology, provided that the sample is preserved in a glutaraldehyde-based tissue fixative. TZ tumors have a propensity to grow larger than their peripheral counterparts without extraprostatic extension and finally to escape the gland by invading the bladder neck. We investigated the value of biopsy-determined parameters including TZ origin to predict the risk of isolated bladder neck invasion at radical prostatectomy. If reliable, this will enable urologists to expand their bladder neck dissection and avoid an isolated positive bladder neck margin. The study cohort consisted of 3942 patients with detailed pre operative biopsy information who underwent curative-intent radical prostatectomy between January 2010 and December 2015 in Western Australia. Multivariate logistic regression models were developed to predict isolated bladder neck invasion or isolated positive bladder neck margin. A predictive preoperative nomogram is presented. The predictive accuracy is shown in the calibration plot (the area under the curve: 0.777). The accuracy of the nomogram is dependent on the biopsy identification of transition zone cancer features, parameters only reliably interpretable after glutaraldehyde tissue fixation.

International Society of Urological Pathology (ISUP) Consensus Conference on Handling and Staging of Radical Prostatectomy Specimens. Working group 5: surgical margins

The 2009 International Society of Urological Pathology Consensus Conference in Boston, made recommendations regarding the standardization of pathology reporting of radical prostatectomy specimens. Issues relating to surgical margin assessment were coordinated by working group 5. Pathologists agreed that tumor extending close to the 'capsular' margin, yet not to it, should be reported as a negative margin, and that locations of positive margins should be indicated as either posterior, posterolateral, lateral, anterior at the prostatic apex, mid-prostate or base. Other items of consensus included specifying the extent of any positive margin as millimeters of involvement; tumor in skeletal muscle at the apical perpendicular margin section, in the absence of accompanying benign glands, to be considered organ confined; and that proximal and distal margins be uniformly referred to as bladder neck and prostatic apex, respectively. Grading of tumor at positive margins was to be left to the discretion of the reporting pathologists. There was no consensus as to how the surgical margin should be regarded when tumor is present at the inked edge of the tissue, in the absence of transected benign glands at the apical margin. Pathologists also did not achieve agreement on the reporting approach to benign prostatic glands at an inked surgical margin in which no carcinoma is present.

International Society of Urological Pathology (ISUP) Consensus Conference on Handling and Staging of Radical Prostatectomy Specimens. Working group 3: extraprostatic extension, lymphovascular invasion and locally advanced disease

The International Society of Urological Pathology Consensus Conference on Handling and Staging of Radical Prostatectomy Specimens in Boston made recommendations regarding the standardization of pathology reporting of radical prostatectomy specimens. Issues relating to extraprostatic extension (pT3a disease), bladder neck invasion, lymphovascular invasion and the definition of pT4 were coordinated by working group 3. It was agreed that prostate cancer can be categorized as pT3a in the absence of adipose tissue involvement when cancer bulges beyond the contour of the gland or beyond the condensed smooth muscle of the prostate at posterior and posterolateral sites. Extraprostatic extension can also be identified anteriorly. It was agreed that the location of extraprostatic extension should be reported. Although there was consensus that the amount of extraprostatic extension should be quantitated, there was no agreement as to which method of quantitation should be employed. There was overwhelming consensus that microscopic urinary bladder neck invasion by carcinoma should be reported as stage pT3a and that lymphovascular invasion by carcinoma should be reported. It is recommended that these elements are considered in the development of practice guidelines and in the daily practice of urological surgical pathology.

The significance of a positive bladder neck margin after radical prostatectomy: the American Joint Committee on Cancer Pathological Stage T4 designation is not warranted

PURPOSE

The American Joint Committee on Cancer currently designates invasion of the bladder neck as a pT4 lesion. However, retrospective analyses have not demonstrated biochemical recurrence-free survival after radical prostatectomy to be consistent with other T4 lesions. We examined biochemical recurrence-free survival and cancer specific survival in men with a positive bladder neck margin.

MATERIALS AND METHODS

Of nearly 17,000 patients in the Johns Hopkins Institutional radical prostatectomy database (1982 to 2008) 198 (1.2%) were identified with a positive bladder neck margin. Kaplan-Meier analyses were used to evaluate biochemical recurrence-free survival and cancer specific survival. A multivariate proportional hazards model predicting biochemical recurrence-free survival and cancer specific survival was fit with prostate specific antigen, Gleason sum and pathological stage to determine the significance of a positive bladder neck margin.

RESULTS

Of the 198 men with a positive bladder neck margin 79 had an isolated bladder neck margin without seminal vesicle or lymph node involvement. The 12-year biochemical recurrence-free survival of men with organ confined disease, extraprostatic extension, seminal vesicle invasion and lymph node involvement without a positive bladder neck margin was 91.1%, 61.1%, 24.5% and 8.1%, respectively. For men with a positive bladder neck margin and those with an isolated positive bladder neck margin biochemical recurrence-free survival was 16.8% and 37.1%, respectively. The 12-year cancer specific survival for men with organ confined disease, extraprostatic extension, seminal vesicle invasion and lymph node involvement without a positive bladder neck margin was 93.5%, 89.0%, 77.0% and 66.8%, respectively. For men with a positive bladder neck margin and those with an isolated positive bladder neck margin cancer specific survival was 78.2% and 92.5%, respectively. A positive bladder neck margin was not a significant predictor of outcome (p = 0.4) on multivariable analysis.

CONCLUSIONS

The incidence of an isolated positive bladder neck margin is low. Men with an isolated positive bladder neck margin after radical prostatectomy experienced a 12-year biochemical recurrence-free survival of 37% and cancer specific survival of 92%, similar to patients with seminal vesicle invasion (pT3b) and extraprostatic extension (pT3a), respectively. The existing American Joint Committee on Cancer classification for prostate cancer should be reconsidered.

The prognostic significance of bladder neck invasion in prostate cancer: is microscopic involvement truly a T4 disease?

Since the widespread of prostate-specific antigen-based screening, prostate cancer at clinical stage T4 has become rare. Most bladder invasion is actually detected on radical prostatectomy specimens as a microscopic bladder neck involvement (BNI). The 2002 Tumour-Node-Metastasis (TNM) classification system classified prostate cancer with BNI within a unified pT4 category and rendered it equivalent to invasion into the pelvic wall musculature or external sphincter; this decision is controversial. Various series have assessed the clinical relevance and the effect of BNI on prognosis. This evidence-based review provides evidence that BNI should be assigned within the subset of pT3 stage, and that further improvement of the actual TNM staging system should be considered. However, BNI remains strongly associated with adverse pathology and should be regarded as a factor that worsens the prognosis of the underlying tumour stage.

Bladder neck involvement as pT4 disease in prostate cancer: implications for prognosis and patient surveillance

Since the use of prostate-specific antigen screening has become widespread, prostate cancer at clinical T4 stage has become rare. Most bladder invasion is actually detected on radical prostatectomy specimens as a microscopic bladder neck involvement (BNI). The 2002 TNM classification system classified prostate cancer with BNI within a unified pT4 category, and rendered it equivalent to invasion into pelvic wall musculature or external sphincter. This decision is controversial. Various series have studied the clinical relevance and the impact of BNI on prognosis. Our evidence-based review provides support to the assignment of BNI within the subset of pT3 stage, and suggests that further improvement of the actual TNM staging system should be considered. However, BNI remains strongly associated with adverse pathology and should be regarded as a factor that worsens the prognosis of the underlying tumor stage.