Role of Volume Weighted Mean Nuclear Volume for Predicting Disease Outcome in Patients with Renal Cell Carcinoma

Grading of renal cell carcinoma by 3D morphological analysis of cell nuclei

This study attempted to develop a method for 3D visualization and quantitative analysis of cell nuclei for renal cell carcinoma (RCC) grading and evaluated the feasibility of such quantitative analysis. We compared the correct classification rate (CCR) for each of the classifiers based on the 2D features of cell nuclei (diameter, area, perimeter, and circularity) and the 3D features of cell nuclei (volume, surface area, and spherical shape factor). The results showed that the classifier using the 3D features provided better results for grading. Our method could overcome the limitations inherent in 2D analysis and could improve the accuracy and reproducibility of quantification of cell nuclei.

Nonmetastatic renal-cell carcinoma: is it really possible to define rational guidelines for post-treatment follow-up?

Defining rational follow-up guidelines in patients treated for cancer is important, from both a medical and an economical perspective. Renal-cell carcinoma is reputed to be unpredictable in its course and only a few, and often contradictory, follow-up guidelines exist for patients treated for nonmetastatic renal-cell carcinoma. Recent advances in tumor biology have contributed to a better understanding of this cancer and have indicated that personalized follow-up regimens, based on tumor and host molecular characteristics, might be possible in the near future.

Pathologic T1 clear cell renal cell carcinoma: Insulin-like growth factor-I receptor expression and disease-specific survival

BACKGROUND

A proportion of patients diagnosed with pathologic T1 (pT1) clear cell renal cell carcinoma (CC-RCC) will experience disease progression and death after surgery, whereas the majority remain disease free. The authors conducted a case-cohort investigation to examine the association of insulin-like growth factor I receptor (IGF-IR) expression and disease-specific survival in patients who underwent surgery for pT1 CC-RCC.

METHODS

Eligible patients included those diagnosed with solitary, nonfamilial pT1 CC-RCC who underwent radical nephrectomy at the Mayo Clinic-Rochester between 1970 and 2000 (n = 886 patients). Among this group, 136 patients died of CC-RCC (cases). Archived tumor blocks were not available for 62 patients, leaving a final study group of 74 cases. Stratified, random sampling was used to select a cohort of at least 3 year-matched controls (no CC-RCC death) for each case (n = 263 patients). Detection of IGF-IR was performed using a commercially available monoclonal antibody. Cox proportional hazards models were fit to assess the association between IGF-IR expression and disease-specific survival.

RESULTS

After adjustment for age, the risk of death from CC-RCC was greater for patients who had tumors that stained positive for IGF-IR compared with patients who had tumors that showed no IGF-IR expression (hazard ratio [HR], 1.5; 95% confidence interval, [95% CI], 0.9-2.4). In a stratified analysis, the risk was stronger among patients who had high-grade tumors (HR, 2.2; 95% CI, 1.1-4.3) compared with patients who had low-grade tumors (HR, 0.7; 95% CI, 0.3-1.5). Multivariate adjustment for tumor size and histologic tumor necrosis attenuated the association among all patients (HR, 1.3; 95% CI, 0.8-2.1) but strengthened the association among patients with high-grade tumors (HR, 2.7; 95% CI, 1.3-5.6).

CONCLUSIONS

The current data suggest that IGF-IR expression is associated with poor survival in patients who are diagnosed with early-stage CC-RCC, especially among those with high-grade disease.

Prognostic significance of nuclear morphometry in renal cell carcinoma

OBJECTIVE

To assess nuclear morphometry as a predictor of prognosis in patients with renal cell carcinoma (RCC).

PATIENTS AND METHODS

The study included 65 consecutive patients with RCC who underwent radical nephrectomy and were followed up for a median (range) of 80 (27-138) months. Nuclear morphometry was assessed using a computer-assisted image analysis system on histological sections and characterized by five nuclear variables (area, perimeter, major and minor diameter, and form factor). From the patients' records and pathology specimens, the clinicopathological prognostic variables (histological type, Fuhrman grade and pathological stage) were recorded. The proliferative activity was assessed using immunohistochemical staining with Ki-67 antibody.

RESULTS

Higher values of mean nuclear area, perimeter, and major and minor diameter were significantly related to higher nuclear grade, proliferative activity and advanced tumour stage. They were significant predictors of disease progression and survival, together with grade, stage, sarcomatoid histology and proliferative activity. Of all significant prognostic factors predicting progression-free survival, only stage was independent (T4 vs T1, hazard ratio 6.55, 95% CI 1.63-26.13, P=0.008).

CONCLUSION

Although the significance of these preliminary results must not be overstated, nuclear morphometry might provide significant prognostic information in predicting survival and tumours at high risk of progression in RCC.

Independent value of tumor size and DNA ploidy for the prediction of disease progression in patients with organ-confined renal cell carcinoma

BACKGROUND

Greater than 20% of patients with apparently localized renal cell carcinoma (RCC) present with disease progression after surgery. The objective of the current study was to improve the ability of clinicians to predict prognosis in patients with localized RCC.

METHODS

The authors studied 154 patients with organ-confined RCC classified as pT1 to pT2-pN0-M0 who underwent radical nephrectomy. Follow-up ranged from 24-128 months (median, 72 months). Several morphologic parameters of the tumor were considered. DNA content was analyzed by flow cytometry and tumor size was determined from the surgical specimen. A Cox proportional hazards regression model was used to identify significant independent prognostic factors for disease progression.

RESULTS

At 5 and 10 years of follow-up, disease free survival was found to be 87% and 86%, respectively. Univariate analysis revealed that DNA content, Furhman grade, and tumor size had a statistically significant predictive value for disease progression, whereas, with regard to grade, the difference was significant only between patients with Grade 3 tumors and all other patients with Grade 1-2 tumors (P < 0. 0001). Although DNA content was found to correlate with tumor size (P < 0.0001), multivariate analysis showed that these were the only significant independent predictors of disease progression. The sum of DNA content and tumor size therefore was considered to distinguish separate risk groups. For a patient with diploid RCC, the risk of progression increased from 4% if the tumor size was 3 cm to 43% if the tumor size was 10 cm. For a patient with nondiploid RCC, this risk was 32% if the tumor size was 3 cm, increasing to 99% for tumors measuring 10 cm.

CONCLUSIONS

Stratification of organ-confined RCC according to tumor size and DNA content could possibly provide more information that could be useful in the selection of individuals with significantly different risks of disease progression.

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.

The role of volume-weighted mean nuclear volume in predicting disease outcome in patients with stage M1 prostate cancer

BACKGROUND

Various factors have been reported to be of value in predicting the prognosis of prostate cancer. Gleason score (GS) and prostate-specific antigen (PSA) are the two most powerful prognosticators among them. We previously reported that estimation of volume-weighted mean nuclear volume (MNV) was a more useful prognosticator for prostate cancer than subjective histologic grading. In this study, we compared estimates of MNV with PSA and GS for predicting the prognosis of stage M1 prostate cancer.

EXPERIMENTAL DESIGN

A retrospective prognostic study of 66 patients with stage M1 prostate cancer diagnosed between January 1989 and December 1996 at Shizuoka City Hospital and Shizuoka Prefectural Hospital was performed. The prognostic value of unbiased estimates of MNV were compared with PSA and histologic grading according to GS.

RESULTS

Univariate analysis revealed that estimates of MNV (p=0.0136) and post-treatment nadir PSA level (p<0.0001) correlated significantly with the prognosis of stage M1 prostate cancer, whilst GS (p=0.9377), pre-treatment PSA level (p=0.7377) and rate of decrease in PSA level within 1 month after the beginning of therapy (p=0.8999) had no prognostic value. Multivariate analysis revealed that post-treatment PSA level and estimates of MNV were the two most powerful prognosticators.

CONCLUSIONS

This study indicates that estimation of MNV is an important prognosticator, in conjunction with post-treatment nadir PSA level, in stage M1 prostate cancer.

Prognostic value of sarcomatoid histology and volume-weighted mean nuclear volume in renal cell carcinoma

OBJECTIVE

To determine the prognostic value of two histopathological factors, sarcomatoid histology and volume-weighted mean nuclear volume (MNV) in renal cell carcinoma (RCC).

PATIENTS AND METHODS

The study included 106 patients (72 men and 34 women, mean age 63 years, range 32-83) with RCC, all of whom were surgically treated between 1985 and 1995. The presence of any sarcomatoid component was determined and MNV estimated using a stereological method in histological slides of tumour specimens from these patients. The prognostic significance of the two variables was evaluated by univariate and multivariate analyses in comparison with other histopathological variables (T, N and M categories, nuclear grade, tumour size, tumour type), using the cause-specific and progression-free survival of the patients as the endpoints.

RESULTS

Among the 106 RCC cases examined, a sarcomatoid component was detected in 34 (32%); the MNV was 90-627 micro3 (mean 225). By univariate and multivariate analysis, both variables were significant prognostic factors for cause-specific survival in all patients. In addition, multivariate analysis of the 74 patients with localized RCCs (T1-3, N0 M0) showed that sarcomatoid histology was a significant prognostic factor for disease progression.

CONCLUSION

The presence of sarcomatoid histology and the MNV, both of which can be examined with no specialized laboratory procedures, seem to be useful tumour-related prognostic factors in RCC.

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.

Volume-weighted mean nuclear volume in renal cell carcinoma

OBJECTIVES

Tumor grade and stage are the most important prognostic parameters for renal cell carcinoma (RCC). The value of histologic nuclear grading, however, is impaired by the inconsistency of pathologists' observations. Estimate of volume-weighted mean nuclear volume (MNV), based on a stereologic method, is correlated with prognosis of bladder, prostate, and endometrial cancer. In this study, we investigated the prognostic value of stereologic estimation of nuclear volume in RCC.

METHODS

This study included 62 patients with RCC who underwent radical nephrectomy between 1989 and 1996. Patients were evaluated in two groups: patients with locally advanced and/or metastatic disease were part of the poor prognosis group and patients with localized disease were part of the good prognosis group. Unbiased estimates of MNV were compared with histologic grade, tumor stage, and growth pattern according to Thoenes classification. Group means were compared using the nonparametric Kruskal-Wallis one-way analysis of variance. Univariate analysis of the data was performed for MNV and time to death, metastasis, local recurrence, and disease-free survival by paired sample t test. For categorical variables, Pearson's correlation test was used for statistical analysis.

RESULTS

There was no correlation between MNV and patient sex, age, tumor stage, and growth pattern. MNV showed a trend to be higher in sarcomatoid and chromophilic cell types than in chromophobe and clear cell types (P < 0.05). MNV values were significantly higher with increasing grades but no MNV cutoff levels could be defined. The MNV values were not different between localized and locally advanced and/or metastatic disease.

CONCLUSIONS

Our results indicate that estimates of MNV are not useful for predicting disease outcome. Further studies are needed to set up reproducible intervals of tumor dedifferentiation that could be carried out in routine practice for predicting progression.

Histologic characteristics of renal cell carcinomas with lymph node metastasis

BACKGROUND

This study was conducted to determine if there are any specific histologic features that are associated with lymph node metastasis in renal cell carcinoma (RCC).

METHODS

TNM classification, histologic grade, mean nuclear volume, cell type, and histologic architecture of the tumors were evaluated in 66 patients who had undergone nephrectomy and lymphadenectomy for RCC. In the 18 patients with positive lymph node metastasis, both primary lesions and metastatic lymph nodes were evaluated.

RESULTS

Lymph node status was correlated with primary tumor stage, venous involvement, and distant metastasis. The tumor grade was higher, and the mean nuclear volume was larger, in both primary and metastatic lesions of RCCs with lymph node metastasis than in tumors with no metastasis. In primary lesions of RCCs with lymph node metastasis, clear cell, alveolar, or cystic patterns were observed less frequently, and granular or spindle/pleomorphic cells and papillary or solid patterns, were observed more frequently, as compared to those lesions without metastasis. Comparison between primary and metastatic lesions in individual patients revealed no significant difference in grade or mean nuclear volume. The development of new cell types or histologic architectures, which was not noted in the primary lesions, was also a rare event in the metastatic lesions.

CONCLUSION

Several characteristic histologic features, which may reflect the increased metastatic potential of the tumor, were observed in both primary and metastatic lesions in cases of RCC with lymph node metastasis. No substantial difference in histologic features was observed between the primary or metastatic lesions of individual patients.