Prognostic criteria in patients with stage D2 prostate cancer. Correlation with mean nuclear volume

Nondestructive 3D pathology with analysis of nuclear features for prostate cancer risk assessment

Prostate cancer treatment decisions rely heavily on subjective visual interpretation [assigning Gleason patterns or International Society of Urological Pathology (ISUP) grade groups] of limited numbers of two-dimensional (2D) histology sections. Under this paradigm, interobserver variance is high, with ISUP grades not correlating well with outcome for individual patients, and this contributes to the over- and undertreatment of patients. Recent studies have demonstrated improved prognostication of prostate cancer outcomes based on computational analyses of glands and nuclei within 2D whole slide images. Our group has also shown that the computational analysis of three-dimensional (3D) glandular features, extracted from 3D pathology datasets of whole intact biopsies, can allow for improved recurrence prediction compared to corresponding 2D features. Here we seek to expand on these prior studies by exploring the prognostic value of 3D shape-based nuclear features in prostate cancer (e.g. nuclear size, sphericity). 3D pathology datasets were generated using open-top light-sheet (OTLS) microscopy of 102 cancer-containing biopsies extracted ex vivo from the prostatectomy specimens of 46 patients. A deep learning-based workflow was developed for 3D nuclear segmentation within the glandular epithelium versus stromal regions of the biopsies. 3D shape-based nuclear features were extracted, and a nested cross-validation scheme was used to train a supervised machine classifier based on 5-year biochemical recurrence (BCR) outcomes. Nuclear features of the glandular epithelium were found to be more prognostic than stromal cell nuclear features (area under the ROC curve [AUC] = 0.72 versus 0.63). 3D shape-based nuclear features of the glandular epithelium were also more strongly associated with the risk of BCR than analogous 2D features (AUC = 0.72 versus 0.62). The results of this preliminary investigation suggest that 3D shape-based nuclear features are associated with prostate cancer aggressiveness and could be of value for the development of decision-support tools. © 2023 The Pathological Society of Great Britain and Ireland.

Comparison of nuclear morphometric results between needle biopsy and surgical specimens from patients with prostate cancer

OBJECTIVES

To compare nuclear morphometric values and Gleason scores between biopsy and radical prostatectomy specimens in patients with clinically localized prostate cancer.

METHODS

The mean nuclear area (MNA), volume-weighted mean nuclear volume (MNV), and form factor (FF) were measured on the 18-gauge needle biopsy and radical prostatectomy specimens of 25 patients with clinically localized prostate cancer. The correlation between biopsy and surgical specimens was investigated for MNA, MNV, FF, and Gleason scores.

RESULTS

The average values for the MNA, MNV, and FF of the biopsy specimens (36.2 microm2, 366 microm3, and 0.86, respectively) were significantly smaller than those of the prostatectomy specimens (51.4 microm2, 646 microm3, and 0.91) by Student's paired t test. The Pearson correlation of morphometric parameters between the biopsy and surgical specimens was significant only for FF. A comparison of histologic grading between the biopsy and surgical specimens revealed identical Gleason scores in 32% and identical grades (on a three-grade system) in 68% of all the cases.

CONCLUSIONS

Discrepant nuclear morphometric results were observed between biopsy and surgical specimens of localized prostate cancer. The reason for such differing results is unclear but may be caused by artifacts associated with tissue sampling and processing. It is recommended that data obtained by biopsy should be considered separately from that obtained from surgical specimens.

The role of volume-weighted mean nuclear volume in predicting disease outcome in patients with prostate cancer treated with radical prostatectomy

BACKGROUND

Estimates of volume-weighted mean nuclear volume (MNV) are the only means by which unbiased estimates of three-dimensional parameters can be obtained from single two-dimensional sections without any assumptions. We have reported that for prostate cancer estimates of MNV are prognostically equal or superior to morphological grading of malignancy, such as Gleason score (GS), and in particular, that MNV proved to be a meaningful predictor of prognosis for patients with clinically localized tumors. However, all previous studies were conducted on patients treated conservatively, and no authors have tested whether estimates of MNV can predict the prognosis of patients treated with radical prostatectomy.

MATERIALS AND METHODS

A retrospective prognostic study of 52 patients with clinically localized prostate cancer diagnosed at three Hospitals in Shizuoka Prefecture, Japan (Shizuoka City Hospital, Shizuoka Prefectural Hospital and Shimada Municipal Hospital) and treated by radical prostatectomy was performed. Twenty of these patients were treated with hormone therapy before radical prostatectomy. Unbiased estimates of MNV were compared with clinical stage, histological grading according to GS and neo-adjuvant hormone therapy with regard to the prognostic value.

RESULTS

MNV was significantly correlated with pathological T stage, but was not significantly correlated with the presence or absence of lymph node metastasis. Univariate analysis revealed that MNV correlated significantly with progression-free survival (p = 0.0116). Multivariate analysis revealed that MNV (p = 0.0115) and GS (p = 0.0275) were two significant independent predictors of progression-free survival.

CONCLUSIONS

The results of the present study suggest that MNV and GS are powerful independent predictors of prognosis for prostate cancer treated with radical prostatectomy. We recommend estimates of MNV as a supportive method to the histological grading for patients with prostate cancer.

Combining volume-weighted mean nuclear volume with Gleason score and clinical stage to predict more reliably disease outcome of patients with prostate cancer

BACKGROUND

Various criteria for patients with prostate cancer have been reported to be of prognostic value, and we have reported that estimates of volume-weighted mean nuclear volume (MNV), developed by Gundersen and Jensen based on a stereological technique, accurately predict the prognosis of prostate cancer. However, all of these studies were conducted on cases in a single institution, and it has remained unclear whether MNV calculations obtained at one institution apply to cases at another institution. In attempting to solve this problem, we made a prognostic index (P.I.) based on data from one hospital, and tested whether these data could be used to predict the prognosis of patients at another hospital.

MATERIALS AND METHODS

A retrospective, multivariate prognostic study of 195 patients with prostate cancer, diagnosed at Kyoto University Hospital and treated conservatively, indicated that clinical stage, Gleason score, and MNV were all significantly correlated with the prognosis of patients with prostate cancer. From the relative strengths of these prognostic factors in a multivariate analysis, the following P.I. was constructed: P.I. = Clinical stage x 1.8040 + Gleason score x 1.5245 + MNV x 2.3162 (the constants correspond to the risk ratio estimated by Cox analysis). The P.I. was calculated for 104 patients with prostate cancer diagnosed at Shizuoka City Hospital and treated conservatively for analysis of disease-specific survival.

RESULTS

The prognostic index ranged from 3.841-16.142. Using the median value of 12.5 as a cutoff point, a clear separation of cases with poor and favorable prognosis was achieved (P < 0.0001, observation period: 1-167 months).

CONCLUSIONS

The results of this study suggest that estimates of MNV can be evaluated at multiple institutions with the use of P.I. calculation. Furthermore, combining estimates of MNV with Gleason score and clinical stage predicts most powerfully disease outcome of patients with prostate cancer.

Intratumoral heterogeneity in prostate cancer demonstrated by volume-weighted mean nuclear volume

This study was conducted to investigate the degree of heterogeneity of the volume-weighted mean nuclear volume (MNV) calculated from radical prostatectomy specimens, and to evaluate how closely the MNV calculated from transrectal biopsy specimens reflected the overall malignancy. MNV was evaluated using 77 sections of histological specimens from 9 patients who underwent radical prostatectomy at Shizuoka City Hospital between January 1990 and December 1995. The MNV values calculated from radical prostatectomy specimens were compared with those calculated from preoperative transrectal biopsy specimens. MNV was judged to be homogeneous in six cases and heterogeneous in three cases. Of the heterogeneous cases, MNV calculated from the transrectal biopsy specimens was judged to be underestimated in 2 of 3 cases. This study shows that intratumoral heterogeneity of prostate cancer may affect clinical estimates of the grade of malignancy based on the MNV, and indicates the need for a sufficient number of specimens in order to evaluate the MNV by transrectal biopsy.

Stereologically estimated mean nuclear volume of prostatic cancer is a reliable prognostic parameter

Although different histological grading systems of prostatic cancer refer to well-described characteristics, results are hard to reproduce. The aim of this study was to obtain morphometric data that would enable objective and reproducible grading of prostatic cancers by stereological estimation of mean nuclear volume (MNV). The clinical records and tissue specimens from 100 patients who were newly diagnosed as having prostatic cancer from 1973 to 1990 and who were followed up for 5 years or longer were retrospectively examined. We analysed the relationship between MNV and clinical stage, Gleason score and histological grading according to the World Health Organization (WHO) classification. To evaluate prognostic predictors, a multivariate analysis of factors associated with cause-specific survival was performed. We found a good correlation between the MNV and clinical stage and between the MNV and histological grading. There was no correlation between MNVs and Gleason scores. Multivariate analysis revealed that the MNV was the only predictor of survival time (coefficient 0.005; P < 0.0001; hazard ratio 1.005). We consider that the MNV is an excellent predictor of the prognosis in patients with prostatic cancer. Moreover, stereological estimation of MNV is a simple, quick, inexpensive and reliable morphometric procedure that enables the quantitative analysis of the histological and biological character of prostatic cancer.

Pretherapeutic erythrocyte polyamine spermine levels discriminate high risk relapsing patients with M1 prostate carcinoma

BACKGROUND

Androgen deprivation is currently the standard treatment for patients with metastatic prostate carcinoma. Few reliable prognostic markers are able to select, at diagnosis, patients who will respond favorably and durably to hormone ablation. Circulating polyamines, markers of cell proliferation that are elevated in prostate carcinoma, have been evaluated as a prognostic tool.

METHODS

Eighty-eight patients with untreated, M1 classified prostate carcinoma who received endocrine therapy between 1988 and 1993 were included in this study. Performance status, hemoglobin, alkaline phosphatases, prostate specific antigen, Gleason tumor grade, extent of disease by bone scan, and circulating erythrocyte spermidine and spermine were correlated with observed progression free and cause-specific survivals. Multiple correspondence analysis and ascending hierarchical classification were performed to determine significant pretreatment prognostic factors.

RESULTS

Pretreatment performance status, alkaline phosphatase, hemoglobin, and erythrocyte spermine levels were correlated with progression, with hemoglobin and erythrocyte spermine level being the most significant independent variables (P < 0.00001 and P < 0.0001, respectively). With regard to cause specific survival, only hemoglobin and spermine erythrocyte levels were significant independent variables (P < 0.0001 and P < 0.0005, respectively). Patients with spermine levels of less than 9 nmol/8.10(9) had a statistically better outcome than patients with 9 nmol/8.10(9) or more erythrocytes. Erythrocyte spermine was the best sole determinant of progression. A test combining spermine with performance status or hemoglobin improved each variable's predictive values.

CONCLUSIONS

Circulating erythrocyte spermine levels, extracted from a blood sample, can discriminate, at diagnosis, patients with hormone-refractory from those with hormone-responsive metastatic prostate carcinoma.