Victor E. Reuter

Integrative Genomic Profiling of Human Prostate Cancer

Annotation of prostate cancer genomes provides a foundation for discoveries that can impact disease understanding and treatment. Concordant assessment of DNA copy number, mRNA expression, and focused exon resequencing in 218 prostate cancer tumors identified the nuclear receptor coactivator NCOA2 as an oncogene in approximately 11% of tumors. Additionally, the androgen-driven TMPRSS2-ERG fusion was associated with a previously unrecognized, prostate-specific deletion at chromosome 3p14 that implicates FOXP1, RYBP, and SHQ1 as potential cooperative tumor suppressors. DNA copy-number data from primary tumors revealed that copy-number alterations robustly define clusters of low- and high-risk disease beyond that achieved by Gleason score. The genomic and clinical outcome data from these patients are now made available as a public resource.

The 2005 International Society of Urological Pathology (ISUP) Consensus Conference on Gleason Grading of Prostatic Carcinoma.

Five years after the last prostatic carcinoma grading consensus conference of the International Society of Urological Pathology (ISUP), accrual of new data and modification of clinical practice require an update of current pathologic grading guidelines. This manuscript summarizes the proceedings of the ISUP consensus meeting for grading of prostatic carcinoma held in September 2019, in Nice, France. Topics brought to consensus included the following: (1) approaches to reporting of Gleason patterns 4 and 5 quantities, and minor/tertiary patterns, (2) an agreement to report the presence of invasive cribriform carcinoma, (3) an agreement to incorporate intraductal carcinoma into grading, and (4) individual versus aggregate grading of systematic and multiparametric magnetic resonance imaging-targeted biopsies. Finally, developments in the field of artificial intelligence in the grading of prostatic carcinoma and future research perspectives were discussed.

Integrative clinical genomics of advanced prostate cancer

Toward development of a precision medicine framework for metastatic, castration-resistant prostate cancer (mCRPC), we established a multi-institutional clinical sequencing infrastructure to conduct prospective whole-exome and transcriptome sequencing of bone or soft tissue tumor biopsies from a cohort of 150 mCRPC affected individuals. Aberrations of AR, ETS genes, TP53, and PTEN were frequent (40%-60% of cases), with TP53 and AR alterations enriched in mCRPC compared to primary prostate cancer. We identified new genomic alterations in PIK3CA/B, R-spondin, BRAF/RAF1, APC, β-catenin, and ZBTB16/PLZF. Moreover, aberrations of BRCA2, BRCA1, and ATM were observed at substantially higher frequencies (19.3% overall) compared to those in primary prostate cancers. 89% of affected individuals harbored a clinically actionable aberration, including 62.7% with aberrations in AR, 65% in other cancer-related genes, and 8% with actionable pathogenic germline alterations. This cohort study provides clinically actionable information that could impact treatment decisions for these affected individuals.

High dose radiation delivered by intensity modulated conformal radiotherapy improves the outcome of localized prostate cancer

PURPOSE We present the long-term outcome and tolerance of 3-dimensional (D) conformal and intensity modulated radiation therapy for localized prostate cancer. MATERIALS AND METHODS Between October 1988 and December 1998, 1,100 patients with clinical stages T1c-T3 prostate cancer were treated with 3-D conformal or intensity modulated radiation therapy. Patients were categorized into prognostic risk groups based on pretreatment prostate specific antigen (PSA), Gleason score and clinical stage. Sextant biopsies were performed 2.5 years or greater after treatment to assess local control. PSA relapse was defined according to the consensus guidelines of the American Society for Therapeutic Radiation Oncology. Late toxicity was classified according to the Radiation Therapy Oncology Group morbidity grading scale. Median followup was 60 months. RESULTS At 5 years the PSA relapse-free survival rate in patients at favorable, intermediate and unfavorable risk was 85% (95% confidence interval [CI] +/- 4), 58% (95% CI +/- 6) and 38% (95% CI +/- 6), respectively (p <0.001). Radiation dose was the most powerful variable impacting PSA relapse-free survival in each prognostic risk group. The 5-year actuarial PSA relapse-free survival rate for patients at favorable risk who received 64.8 to 70.2 Gy. was 77% (95% CI +/- 8) compared to 90% (95% CI +/- 8) for those treated with 75.6 to 86.4 Gy. (p = 0.04) [corrected]. The corresponding rates were 50% (95% CI +/- 8) versus 70% (95% CI +/- 6) in intermediate risk cases (p = 0.001), and 21% (95% CI +/- 8) versus 47% (95% CI +/- 6) in unfavorable risk cases (p = 0.008) [corrected]. Only 4 of 41 patients (10%) who received 81 Gy. had a positive biopsy 2.5 years or greater after treatment compared with 27 of 119 (23%) after 75.6, 23 of 68 (34%) after 70.2 and 13 of 24 (54%) after 64.8 Gy. The incidence of toxicity after 3-D conformal radiation therapy was dose dependent. The 5-year actuarial rate of grade 2 rectal toxicity in patients who received 75.6 Gy. or greater was 14% (95% CI +/- 2) compared with 5% (95% CI +/- 2) in those treated at lower dose levels (p <0.001). Treatment with intensity modulated radiation therapy significantly decreased the incidence of late grade 2 rectal toxicity since the 3-year actuarial incidence in 189 cases managed by 81 Gy. was 2% (95% CI +/- 2) compared with 14% (95% CI +/- 2) in 61 managed by the same dose of 3-D conformal radiation therapy (p = 0.005). The 5-year actuarial rate of grade 2 urinary toxicity in patients who received 75.6 Gy. or greater 3-D conformal radiation therapy was 13% compared with 4% in those treated up to lower doses (p <0.001). Intensity modulated radiation therapy did not affect the incidence of urinary toxicity. CONCLUSIONS Sophisticated conformal radiotherapy techniques with high dose 3-D conformal and intensity modulated radiation therapy improve the biochemical outcome in patients with favorable, intermediate and unfavorable risk prostate cancer. Intensity modulated radiation therapy is associated with minimal rectal and bladder toxicity, and, hence, represents the treatment delivery approach with the most favorable risk-to-benefit ratio.

Prognostic Factors for Survival in Previously Treated Patients With Metastatic Renal Cell Carcinoma

PURPOSE To describe survival in previously treated patients with metastatic renal cell carcinoma (RCC) who are candidates for clinical trials of new agents as second-line therapy. PATIENTS AND METHODS The relationship between pretreatment clinical features and survival was studied in 251 patients with advanced RCC treated during 29 consecutive clinical trials between 1975 and 2002. Clinical features were first examined in univariate analyses, and then a stepwise modeling approach based on Cox regression was used to form a multivariate model. RESULTS Median survival for the 251 patients was 10.2 months and differed according to year of treatment, with patients treated after 1990 showing longer survival. In this group, the median overall survival time was 12.7 months. Because the purpose of this analysis was to establish prognostic factors for present-day clinical trial design, prognostic factor analysis was performed on these patients. Pretreatment features associated with a shorter survival in the multivariate analysis were low Karnofsky performance status, low hemoglobin level, and high corrected serum calcium. These were used as risk factors to categorize patients into three different groups. The median time to death in patients with zero risk factors was 22 months. The median survival in patients with one of these prognostic factors was 11.9 months. Patients with two or three risk factors had a median survival of 5.4 months. CONCLUSION Treatment with novel agents during a clinical trial is indicated for patients with metastatic RCC after progression to cytokine treatment. Three prognostic factors for predicting survival were used to categorize patients into risk groups. These risk categories can be used in clinical trial design and interpretation.

A POSTOPERATIVE PROGNOSTIC NOMOGRAM FOR RENAL CELL CARCINOMA

PURPOSE Few published studies have combined prognostic factors to predict the likelihood of recurrence after surgery for renal cell carcinoma. We developed a nomogram for this purpose. MATERIALS AND METHODS With Cox proportional hazards regression analysis, we modeled pathological data and disease followup for 601 patients with renal cell carcinoma who were treated with nephrectomy. Predictor variables were patient symptoms, including incidental, local or systemic, histology, including chromophobe, papillary or conventional, tumor size, and pathological stage. Treatment failure was recorded when there was either clinical evidence of disease recurrence or death from disease. Validation was performed with a statistical (bootstrapping) technique. RESULTS Disease recurrence was noted in 66 of the 601 patients, and those in whom treatment was successful had a median and maximum followup of 40 and 123 months, respectively. The 5-year probability of freedom from failure for the patient cohort was 86% (95% confidence interval 82 to 89). With statistical validation, predictions by the nomogram appeared accurate and discriminating with an area under the receiver operating characteristic curve, that is a comparison of the predicted probability with the actual outcome of 0.74. CONCLUSIONS A nomogram has been developed that can be used to predict the 5-year probability of treatment failure among patients with newly diagnosed renal cell carcinoma. The nomogram may be useful for patient counseling, clinical trial design and patient followup planning.

Surgical management of renal tumors 4 cm. or less in a contemporary cohort.

PURPOSE We evaluated a patient cohort with renal tumors 4 cm. or less treated with partial or radical nephrectomy. We compared patient and tumor characteristics, and survival in these 2 groups. MATERIALS AND METHODS We retrospectively analyzed the records of 670 patients with a median age of 63 years treated surgically for renal cell carcinoma between July 31, 1989 and July 31, 1997. Renal tumors 4.0 cm. or less were noted in 252 patients (38%) who underwent a total of 262 procedures, including 183 radical (70%) and 79 partial (30%) nephrectomies. Ten patients required 2 operations each because of bilateral renal cell carcinoma. Median followup was 40 months. We compared clinicopathological parameters in the partial and radical nephrectomy groups using chi-square or Wilcoxon analysis as appropriate. Survival analysis was determined by the log rank test and Cox regression model. RESULTS The partial and radical nephrectomy groups were comparable with respect to gender ratio, tumor presentation, histological classification, pathological stage and complication rate. Median tumor size was 2.5 and 3.0 cm. in the partial and radical nephrectomy groups, respectively (p = 0.0001). Resection was incomplete in 1 patient (1.3%) in the partial and none in the radical nephrectomy group. There was no local recurrence after either procedure, and no significant difference in disease specific, disease-free and overall survival (p = 0.98, 0.23 and 0.20, respectively). CONCLUSIONS Patients with a small renal tumor have similar perioperative morbidity, pathological stage and outcome regardless of treatment with partial or radical nephrectomy. Therefore, partial nephrectomy remains a safe alternative for tumors of this size.

Impact of the number of lymph nodes retrieved on outcome in patients with muscle invasive bladder cancer.

Purpose: We postulate that the number of lymph nodes examined in cystectomy specimens can have an impact on the outcome of patients with bladder cancer.Materials and Methods: We analyzed data on 322 patients with muscle invasive bladder cancer who underwent radical cystectomy and bilateral pelvic lymphadenectomy. We evaluated the associations of the number of lymph nodes identified by the pathologist in the surgical specimen with the local recurrence rate and survival outcome.Results: Patients were divided into groups by lymph node status and the distribution of the number of lymph nodes examined. In stages pN0 and pN+ cases improved survival was associated with a greater number of lymph nodes examined. We determined that at least 9 lymph nodes should be studied to define lymph node status accurately.Conclusions: These results indicate that surgical resection and pathological assessment of an adequate number of lymph nodes in cystectomy specimens increases the likelihood of proper staging and impacts pati...

Gene Expression Analysis of Human Prostate Carcinoma during Hormonal Therapy Identifies Androgen-Responsive Genes and Mechanisms of Therapy Resistance

The androgen-signaling pathway is critical to the development and progression of prostate cancer and androgen ablation is a mainstay of therapy for this disease. We performed a genome-wide expression analysis of human prostate cancer during androgen ablation therapy to identify genes regulated by androgen and genes differentially expressed after the development of resistance. Six hundred and fifty-four of 63,175 probe sets detected significant expression changes after 3 months of treatment with goserelin and flutamide. This included 149 genes that were also differentially expressed 36 hours after androgen withdrawal in LNCaP cells. These genes reflect the physiological changes that occur in treated tumors and include potential direct targets of the androgen receptor. Expression profiles of androgen ablation-resistant tumors demonstrated that many of the gene expression changes detected during therapy were no longer present suggesting a reactivation of the androgen response pathway in the absence of exogenous hormone. Therapy resistance was associated with differential expression of a unique set of genes that reflect potential mechanisms of reactivation. Specifically an up-regulation of the androgen receptor and key enzymes for steroid biosynthesis suggest that resistant tumors have increased sensitivity to and endogenous synthesis of androgenic hormones. The specific pathways of reactivation provide opportunities for classification of resistant tumors and targeted therapies.

Primary Renal Neoplasms with the ASPL-TFE3 Gene Fusion of Alveolar Soft Part Sarcoma A Distinctive Tumor Entity Previously Included among Renal Cell Carcinomas of Children and Adolescents

The unbalanced translocation, der(17)t(X;17)(p11.2;q25), is characteristic of alveolar soft part sarcoma (ASPS). We have recently shown that this translocation fuses the TFE3 transcription factor gene at Xp11.2 to ASPL, a novel gene at 17q25. We describe herein eight morphologically distinctive renal tumors occurring in young people that bear the identical ASPL-TFE3 fusion transcript as ASPS, with the distinction that the t(X;17) translocation is cytogenetically balanced in these renal tumors. A relationship between these renal tumors and ASPS was initially suggested by the cytogenetic finding of a balanced t(X;17)(p11.2;q25) in two of the cases, and the ASPL-TFE3 fusion transcripts were then confirmed by reverse transcriptase-polymerase chain reaction. The morphology of these eight ASPL-TFE3 fusion-positive renal tumors, although overlapping in some aspects that of classic ASPS, more closely resembles renal cell carcinoma (RCC), which was the a priori diagnosis in all cases. These tumors demonstrate nested and pseudopapillary patterns of growth, psammomatous calcifications, and epithelioid cells with abundant clear cytoplasm and well-defined cell borders. By immunohistochemistry, four tumors were negative for all epithelial markers tested, whereas four were focally positive for cytokeratin and two were reactive for epithelial membrane antigen (EMA) (one diffusely, one focally). Electron microscopy of six tumors demonstrated a combination of ASPS-like features (dense granules in four cases, rhomboid crystals in two cases) and epithelial features (cell junctions in six cases, microvilli and true glandular lumens in three cases). Overall, although seven of eight tumors demonstrated at least focal epithelial features by electron microscopy or immunohistochemistry, the degree and extent of epithelial differentiation was notably less than expected for typical RCC. We confirmed the balanced nature of the t(X;17) translocation by fluorescence in situ hybridization in all seven renal tumors thus analyzed, which contrasts sharply with the unbalanced nature of the translocation in ASPS. In summary, a subset of tumors previously considered to be RCC in young people are in fact genetically related to ASPS, although their distinctive morphological and genetic features justify their classification as a distinctive neoplastic entity. Finally, the finding of distinctive tumors being associated with balanced and unbalanced forms of the same translocation is to our knowledge, unprecedented.