Tumor amount in prostatic tissues in relation to patient outcome and management

The role of histopathological and biochemical parameters for predicting metastatic disease on 68 Ga-PSMA-11 PET in prostate cancer

BACKGROUND

The aim of this study was to evaluate the role of histopathological and biochemical parameters in the prediction of the presence and number of PSMA positive lesions consistent with the metastatic spread of prostate cancer on ⁶⁸ Ga-PSMA PET images.

METHODS

Biochemical, histopathological and imaging data of 302 prostate cancer patients who underwent ⁶⁸ Ga-PSMA-11 PET/CT or PET/MR imaging for primary staging were retrospectively analyzed. Patients were divided into two groups as "PET positive" and "PET negative" according to the presence of pathologic extraprostatic PSMA involvement. "PET positive" patients were additionally divided into two groups: oligometastatic (1-3 metastatic lesion) and multimetastatic (>3 metastatic lesions).

RESULTS

The mean age of patients was 66.8 ± 7.6 years. Imaging modality was PET/MR in 223 (73.8%) and PET/CT in 79 (26.2%) of patients. Total PSA, PSA density (PSAD), ALP, and tumor ratio in biopsy specimens were found to be significantly higher in "PET positive" group compared to "PET negative" group and in multimetastatic group compared to oligometastatic group. PET positivity was observed in 3.8% of the low-intermediate risk groups (ISUP 1-3 and total PSA ≤ 20 ng/ml and PSAD < 0.15 ng/ml/cc). This ratio was 46% in the high-risk group (ISUP 4-5 or total PSA > 20 ng/ml or PSAD ≥ 0.15 ng/ml/cc) with a relative risk of 12 (p < .001). The prediction models to predict the PET positivity and the presence of distant metastasis had AUCs of 0.901 and 0.925, respectively; with ALP, total PSA, and tumor ratio in needle biopsy specimen as significant independent predictors (p < .05).

CONCLUSIONS

In this study, ⁶⁸ Ga-PSMA-11 PET positivity was significantly higher in the high-risk patient group than in the low-intermediate risk groups. The prediction models used for predicting the PET positivity and the presence of distant metastasis on PET imaging were successful with high discriminatory powers. In addition to total PSA and ISUP GG, ALP and tumor ratio in biopsy specimens can be used to identify high-risk patients.

The critical role of the pathologist in determining eligibility for active surveillance as a management option in patients with prostate cancer: consensus statement with recommendations supported by the College of American Pathologists, International Society of Urological Pathology, Association of Directors of Anatomic and Surgical Pathology, the New Zealand Society of Pathologists, and the Prostate Cancer Foundation

CONTEXT

Prostate cancer remains a significant public health problem. Recent publications of randomized trials and the US Preventive Services Task Force recommendations have drawn attention to overtreatment of localized, low-risk prostate cancer. Active surveillance, in which patients undergo regular visits with serum prostate-specific antigen tests and repeat prostate biopsies, rather than aggressive treatment with curative intent, may address overtreatment of low-risk prostate cancer. It is apparent that a greater awareness of the critical role of pathologists in determining eligibility for active surveillance is needed.

OBJECTIVES

To review the state of current knowledge about the role of active surveillance in the management of prostate cancer and to provide a multidisciplinary report focusing on pathologic parameters important to the successful identification of patients likely to succeed with active surveillance, to determine the role of molecular tests in increasing the safety of active surveillance, and to provide future directions.

DESIGN

Systematic review of literature on active surveillance for low-risk prostate cancer, pathologic parameters important for appropriate stratification, and issues regarding interobserver reproducibility. Expert panels were created to delineate the fundamental questions confronting the clinical and pathologic aspects of management of men on active surveillance.

RESULTS

Expert panelists identified pathologic parameters important for management and the related diagnostic and reporting issues. Consensus recommendations were generated where appropriate.

CONCLUSIONS

Active surveillance is an important management option for men with low-risk prostate cancer. Vital to this process is the critical role pathologic parameters have in identifying appropriate candidates for active surveillance. These findings need to be reproducible and consistently reported by surgical pathologists with accurate pathology reporting.

A modified point count method as a practical approach to assess the tumor volume and the percent gland involvement by prostate carcinoma

This study reports a modified point-count method for quantifying the extent of carcinoma in prostatectomy specimens (n=143), as adapted from Billis et al. (2003) [3]. The prostates were studied as follows: the basal/apical margins were sampled using the cone method. The remainder of the gland was divided into 12 quadrant-shaped regions that were sampled using two slices. Eight equidistant points were marked directly on the coverslip over each fragment. The points inside the tumoral areas were counted and expressed as both the percentage of prostate gland involvement by carcinoma (PGI) and the tumor volume (TV). A significant correlation between the preoperative PSA levels and each of the three quantitative estimations were observed, with improved correlations with the PGI and TV values obtained using the point-count method (viz. number of slices involved (NSI) (r=0.32), PGI (r=0.39) and TV (r=0.44)). With the data sets stratified into three categories, all three methods correlated with multiple parameters, including Gleason scores ≥7, primary Gleason scores ≥4, perineural/angiolymphatic invasion, extraprostatic extension, seminal vesicle invasion and positive margins. All three quantitative methods were associated with morphologic features of tumor progression. The results obtained using this modified point-count method correlate more strongly with preoperative PSA levels.

Analysis of preoperative detection for apex prostate cancer by transrectal biopsy

Background. The aim of this study was to determine concordance rates for prostatectomy specimens and transrectal needle biopsy samples in various areas of the prostate in order to assess diagnostic accuracy of the transrectal biopsy approach, especially for presurgical detection of cancer in the prostatic apex. Materials and Methods. From 2006 to 2011, 158 patients whose radical prostatectomy specimens had been evaluated were retrospectively enrolled in this study. Concordance rates for histopathology results of prostatectomy specimens and needle biopsy samples were evaluated in 8 prostatic sections (apex, middle, base, and transitional zones bilaterally) from 73 patients diagnosed at this institution, besides factors for detecting apex cancer in total 118 true positive and false negative apex cancers. Results. Prostate cancer was found most frequently (85%) in the apex of all patients. Of 584 histopathology sections, 153 (49%) from all areas were false negatives, as were 45% of apex biopsy samples. No readily available preoperative factors for detecting apex cancer were identified. Conclusions. In Japanese patients, the most frequent location of prostate cancer is in the apex. There is a high false negative rate for transrectal biopsy samples. To improve the detection rate, transperitoneal biopsy or more accurate imaging technology is needed.