DNA ploidy and PTEN as biomarkers for predicting aggressive disease in prostate cancer patients under active surveillance.

BACKGROUND: Current risk stratification tools for prostate cancer patients under active surveillance (AS) may inadequately identify those needing treatment. We investigated DNA ploidy and PTEN as potential biomarkers to predict aggressive disease in AS patients. METHODS: We assessed DNA ploidy by image cytometry and PTEN protein expression by immunohistochemistry in 3197 tumour-containing tissue blocks from 558 patients followed in AS at a Norwegian local hospital. The primary endpoint was treatment, with treatment failure (biochemical recurrence or initiation of salvage therapy) as the secondary endpoint. RESULTS: The combined DNA ploidy and PTEN (DPP) status at diagnosis was associated with treatment-free survival in univariable- and multivariable analysis, with a HR for DPP-aberrant vs. DPP-normal tumours of 2.12 (p < 0.0001) and 1.94 (p < 0.0001), respectively. Integration of DNA ploidy and PTEN status with the Cancer of the Prostate Risk Assessment (CAPRA) score improved risk stratification (c-index difference = 0.025; p = 0.0033). Among the treated patients, those with DPP-aberrant tumours exhibited a significantly higher likelihood of treatment failure (HR 2.01; p = 0.027). CONCLUSIONS: DNA ploidy and PTEN could serve as additional biomarkers to identify AS patients at increased risk of developing aggressive disease, enabling earlier intervention for nearly 50% of the patients that will eventually receive treatment with current protocol.

Impact of molecular profile on prognosis and relapse pattern in low and intermediate risk endometrial cancer.

INTRODUCTION: The role of molecular classification in patients with low/intermediate risk endometrial cancer (EC) is uncertain. Higher precision in diagnostics will inform the unsettled debate on optimal adjuvant treatment. We aimed to determine the association of molecular profiling with patterns of relapse and survival. MATERIAL AND METHODS: This retrospective cohort study included patients referred to The Norwegian Radium Hospital, Oslo University Hospital from 2006-2017. Patients with low/intermediate risk EC were molecularly classified as pathogenic polymerase epsilon (POLE)-mutated, mismatch repair deficient (MMRd), p53 abnormal, or no specific molecular profile (NSMP). The main outcomes were time to recurrence (TTR) and cancer-specific survival (CSS). RESULTS: Of 626 patients, 610 could be molecularly classified. Fifty-seven patients (9%) had POLE-mutated tumors, 202 (33%) had MMRd tumors, 34 (6%) had p53 abnormal tumors and 317 (52%) had NSMP tumors. After median follow-up time of 8.9 years, there was a statistically significant difference in TTR and CSS by molecular groups. Patients with p53 abnormal tumors had poor prognosis, with 10 of the 12 patients with relapse presenting with para-aortic/distant metastases. Patients with POLE mutations had excellent prognosis. In the NSMP group, L1CAM expression was associated with shorter CSS but not TTR. CONCLUSIONS: The differences in outcome by molecular groups are driven by differences in relapse frequency and -patterns and demand a higher precision in diagnostics, also in patients with low/intermediate risk EC. Tailored adjuvant treatment strategies need to consider systemic treatment for patients with p53 abnormal tumors and de-escalated treatment for patients with POLE mutated tumors.

Prostate cancer radiogenomics reveals proliferative gene expression programs associated with distinct MRI-based hypoxia levels.

BACKGROUND AND PURPOSE: The biology behind individual hypoxia levels in patient tumors is poorly understood. Here, we used radiogenomics to identify associations between magnetic resonance imaging (MRI)-based hypoxia levels and biological processes derived from gene expression data in prostate cancer. MATERIALS AND METHODS: For 85 prostate cancer patients, MRI-based hypoxia images were constructed by combining diffusion-weighted images reflecting oxygen consumption and supply. The ability to differentiate hypoxia levels in these images was verified by comparison with matched biopsy sections stained for the hypoxia marker pimonidazole. For MRI-defined hypoxia levels, corresponding hypoxic fractions were calculated and correlated with biopsy gene expression profiles. Biological processes were predicted by gene set enrichment analysis (GSEA) and validated by immunohistochemistry (Ki67 proliferation marker, reactive stroma grade) and RT-PCR (MYC). RESULTS: Genes with correlation between expression level and hypoxic fraction were identified for 56 MRI-based hypoxia levels. At all levels, GSEA identified proliferation as the predominant biological process enriched among the correlating genes. Two independent proliferative gene signatures were developed. The Peak1 signature, upregulated at moderate/severe hypoxia, reflected MYC upregulation and high Ki67-proliferation index of cancer cells in pimonidazole-positive regions. The Peak2 signature, upregulated at mild to non-hypoxic levels, was associated with fibroblast gene signature and reactive stroma grade. High scores of both Peak1 and Peak2 indicated elevated risk of biochemical recurrence in multiple cohorts. CONCLUSION: Radiogenomics identified two gene expression programs activated at different hypoxia levels, reflecting proliferation of cancer cells and stroma cells. Genes involved in these programs could be candidate targets for intervention.

A prognostic hypoxia gene signature with low heterogeneity within the dominant tumour lesion in prostate cancer patients.

BACKGROUND: Gene signatures measured in a biopsy have been proposed as hypoxia biomarkers in prostate cancer. We assessed a previously developed signature, and aimed to determine its relationship to hypoxia and its heterogeneity within the dominant (index) lesion of prostate cancer. METHODS: The 32-gene signature was assessed from gene expression data of 141 biopsies from the index lesion of 94 patients treated with prostatectomy. A gene score calculated from the expression levels was applied in the analyses. Hypoxic fraction from pimonidazole immunostained whole-mount and biopsy sections was used as reference standard for hypoxia. RESULTS: The gene score was correlated with pimonidazole-defined hypoxic fraction in whole-mount sections, and the two parameters showed almost equal association with clinical markers of tumour aggressiveness. Based on the gene score, incorrect classification according to hypoxic fraction in whole-mount sections was seen in one third of the patients. The incorrect classifications were apparently not due to intra-tumour heterogeneity, since the score had low heterogeneity compared to pimonidazole-defined hypoxic fraction in biopsies. The score showed prognostic significance in uni-and multivariate analysis in independent cohorts. CONCLUSIONS: Our signature from the index lesion reflects tumour hypoxia and predicts prognosis in prostate cancer, independent of intra-tumour heterogeneity in pimonidazole-defined hypoxia.

Localization of primary prostate cancer: FACBC PET/CT compared with multiparametric MRI using histopathology as reference standard.

FACBC (anti-1-amino-3-18F-fluorocyclobutane-1-carboxylic acid) is a FDA-approved PET-tracer in patients with suspected recurrent prostate cancer. In the diagnostic work-up of primary prostate cancer, accurate localization of the index tumor is needed for image-guidance of biopsies. We therefore assessed the performance of FACBC PET/CT to detect and localize the index tumor and compared it to multiparametric MRI (mpMRI) using whole-mount histopathology as reference standard. Twenty-three patients with biopsy-proven prostate cancer had FACBC PET/CT and mpMRI within two weeks prior to prostatectomy. FACBC PET/CT was acquired as 14 minutes list-mode and re-binned into seven 2-minutes intervals. Static FACBC was the acquired data from 4-6 minutes, whereas the dynamic FACBC included all seven intervals. Two radiologists and two nuclear medicine physicians independently interpreted the images and consensus was reached in case of discrepancy. Static PET detected 15 of 23 (65%) of the index tumors, dynamic PET detected 14 of 22 (64%), and MRI detected 20 of 23 (87%). To assess the extent of the tumor, the interpreters delineated the tumor in a 12-regions sector-based template. True positive, true negative, false positive and false negative sectors were recorded based on the template drawings and whole-mount histopathology. Both static and dynamic FACBC PET had sensitivity of 40% and specificity of 99%, whereas MRI had sensitivity of 81% and specificity of 100%. Our data indicate that FACBC PET/CT may be useful but that mpMRI is better for localizing the index tumor in patients with prostate cancer.

PTEN and DNA Ploidy Status by Machine Learning in Prostate Cancer.

Machine learning (ML) is expected to improve biomarker assessment. Using convolution neural networks, we developed a fully-automated method for assessing PTEN protein status in immunohistochemically-stained slides using a radical prostatectomy (RP) cohort (n = 253). It was validated according to a predefined protocol in an independent RP cohort (n = 259), alone and by measuring its prognostic value in combination with DNA ploidy status determined by ML-based image cytometry. In the primary analysis, automatically assessed dichotomized PTEN status was associated with time to biochemical recurrence (TTBCR) (hazard ratio (HR) = 3.32, 95% CI 2.05 to 5.38). Patients with both non-diploid tumors and PTEN-low had an HR of 4.63 (95% CI 2.50 to 8.57), while patients with one of these characteristics had an HR of 1.94 (95% CI 1.15 to 3.30), compared to patients with diploid tumors and PTEN-high, in univariable analysis of TTBCR in the validation cohort. Automatic PTEN scoring was strongly predictive of the PTEN status assessed by human experts (area under the curve 0.987 (95% CI 0.968 to 0.994)). This suggests that PTEN status can be accurately assessed using ML, and that the combined marker of automatically assessed PTEN and DNA ploidy status may provide an objective supplement to the existing risk stratification factors in prostate cancer.

Amino acid transporter expression and 18F-FACBC uptake at PET in primary prostate cancer.

Little is known about the transport mechanism of anti-3-18F-fluorocyclobutane-1-carboxylic acid (FACBC) into prostate tumors. Because of the structural similarity to natural amino acids, FACBC is anticipated to cross the cell membrane via amino acid transporters, and preclinical studies have suggested that ASCT2, LAT1 and SNAT2 are involved. In 16 patients with intermediate or high-risk prostate cancer we matched the FACBC uptake from clinical PET to the location of punch biopsies from resected prostatectomy specimens and compared maximum standardized uptake value (SUVmax) with the gene expression of 40 amino acid transporters. The study also included immunohistochemistry for the three amino acid transporters ASCT2, LAT1 and SNAT2. Furthermore, we performed global gene expression analysis of the biopsies to investigate biological processes associated with FACBC uptake. Several amino acid transporters had a higher gene expression level than the others, but we found no significant correlations between SUVmax and the gene expression levels of any of 40 different amino acid transporters. In the immunohistochemical analyses, ASCT2 and SNAT2 were highly expressed, but not correlated to SUVmax. LAT1 had low gene- and protein expression. Global gene expression analyses identified 153 unique genes that were positively correlated to SUVmax. These genes were found to be associated with gene sets reflecting intracellular transport and high metabolic activity. Based on the study findings we propose that the uptake mechanism of FACBC is more complex than mediated by a few amino acid transporters.

Increased curative treatment is associated with decreased prostate cancer-specific and overall mortality in senior adults with high-risk prostate cancer; results from a national registry-based cohort study.

BACKGROUND: The association between curative treatment (CurTrt) and mortality in senior adults (≥70 years) with high-risk prostate cancer (PCa) is poorly documented. In a population-based cohort we report temporal trends in treatment and PCa-specific mortality (PCSM), investigating the association between CurTrt and mortality in senior adults with high-risk PCa, compared to findings in younger men (<70 years). METHODS: Observational study from the Cancer Registry of Norway. Patients with high-risk PCa were stratified for three diagnostic periods (2005-08, 2009-12 and 2013-16), age (<70, vs ≥70) and primary treatment (CurTrt: Radical prostatectomy (RP), Radiotherapy (RAD) vs no curative treatment (NoCurTrt)). Competing risk and Kaplan-Meier methods estimated PCSM and overall mortality (OM), respectively. Multivariable logistic regression models estimated odds for CurTrt, and multivariable Fine Gray and Cox regression models evaluated the hazard ratios for PCSM and OM. RESULTS: Of 19 763 evaluable patients, 54% were aged ≥70 years. Senior adults had more unfavorable PCa characteristics than younger men. Across diagnostic periods, use of CurTrt increased from 15% to 51% in men aged ≥70 and 65% to 81% in men aged < 70 years. With median five years follow-up, PCSM decreased in all patients (P < .05), in the third period restricted to senior adults. In all patients NoCurTrt was associated with three-fold higher 5-year PCSM and two-fold higher OM compared to CurTrt. CONCLUSIONS: In high-risk PCa patients, increased use of CurTrt, greatest in senior men, was observed along with decreased PCSM and OM in both senior and younger adults. CurTrt should increasingly be considered in men ≥70 years.

Biphasic Hyalinizing Psammomatous Renal Cell Carcinoma (BHP RCC): A Distinctive Neoplasm Associated With Somatic NF2 Mutations.

We report 8 cases of a distinctive, previously undescribed renal cell carcinoma associated with somatic mutations in the neurofibromin 2 (NF2) gene. All patients were adults, ranging from 51 to 78 years of age and of cases of known sex 6 of 7 were males. The carcinomas were predominantly unencapsulated, and all had a rounded, nodular interface with the native kidney. The neoplasms were all solid with papillary architecture evident in most cases (7/8), while 1 was only tubular. All cases were biphasic, characterized by larger and smaller carcinoma cells. The smaller cells clustered around basement membrane material similar to the characteristic pattern of the t(6;11) renal cell carcinoma associated with TFEB gene fusions. In 6 of 8 carcinomas, branching nodules of small cells clustered around basement membrane material within larger acini yielding a distinctive glomeruloid pattern. In 6 of 8 carcinomas, the small cells were focally spindle-shaped and unassociated with the basement membrane material. The stroma was sclerotic in all 8 carcinomas, and all 8 contained psammoma bodies that were abundant in 2. In some carcinomas, focal or predominant areas had a less distinctive appearance; 2 had areas that resembled clear cell renal cell carcinoma, 2 had high-grade eosinophilic areas, while 1 had branching tubular architecture that resembled mucinous tubular and spindle cell carcinoma. Two carcinomas demonstrated cellular necrosis. Although we have minimal clinical follow-up, 1 case presented with distant metastasis, progressed and resulted in patient death. While NF2 mutations may be found in other established renal cell carcinoma subtypes (often as secondary genetic alterations), they are potentially the genetic driver of this distinctive entity.

Prognostic value of mitotic checkpoint protein BUB3, cyclin B1, and pituitary tumor-transforming 1 expression in prostate cancer.

The mitotic checkpoint protein BUB3, cyclin B1 (CCNB1) and pituitary tumor-transforming 1 (PTTG1) regulates cell division, and are sparsely studied in prostate cancer. Deregulation of these genes can lead to genomic instability, a characteristic of more aggressive tumors. We aimed to determine the expression levels of BUB3, CCNB1, and PTTG1 as potential prognostic markers of recurrence after radical prostatectomy. Protein levels were determined by immunohistochemistry on three formalin-fixed paraffin-embedded tissue sections from each of the 253 patients treated with radical prostatectomy. Immunohistochemistry scores were obtained by automated image analysis for CCNB1 and PTTG1. Recurrence, defined as locoregional recurrence, distant metastasis or death from prostate cancer, was used as endpoint for survival analysis. Tumors having both positive and negative tumor areas for cytoplasmic BUB3 (30%), CCNB1 (28%), or PTTG1 (35%) were considered heterogeneous. Patients with ≥1 positive tumor area had significantly increased risk of disease recurrence in univariable analysis compared with patients where all tumor areas were negative for cytoplasmic BUB3 (hazard ratio [HR] = 2.18, 95% confidence interval [CI] 1.41-3.36), CCNB1 (HR = 2.98, 95% CI 1.93-4.61) and PTTG1 (HR = 1.91, 95% CI 1.23-2.97). Combining the scores of cytoplasmic BUB3 and CCNB1 improved risk stratification when integrated with the Cancer of the Prostate Risk Assessment post-Surgical (CAPRA-S) score (difference in concordance index = 0.024, 95% CI 0.001-0.05). In analysis of multiple tumor areas, prognostic value was observed for cytoplasmic BUB3, CCNB1, and PTTG1.

Prognostic value of DNA ploidy and automated assessment of stroma fraction in prostate cancer.

The combination of DNA ploidy and automatically estimated stroma fraction has been shown to correlate with recurrence and cancer death in colorectal cancer. We aimed to extend this observation and evaluate the prognostic importance of this combined marker in prostate cancer. DNA ploidy status was determined by image cytometry and the stroma fraction was estimated automatically on hematoxylin and eosin stained sections in three tumor samples from each patient to account for tumor heterogeneity. The optimal threshold for low (≤56%) and high (>56%) stroma fraction was identified in a discovery cohort (n = 253). The combined marker was validated in an independent patient cohort (n = 259) with biochemical recurrence as endpoint. The combined marker predicted biochemical recurrence independently in the validation cohort. Multivariable analysis showed that the highest risk of recurrence was observed for patients with samples that had both non-diploid ploidy status and a high stroma fraction (hazard ratio: 2.51, 95% confidence interval: 1.18-5.34). In conclusion, we suggest the combination of DNA ploidy and automatically estimated stroma fraction as a prognostic marker for the risk stratification of prostate cancer patients. It may also be a potential generic marker as concurrent results have been described in colorectal cancer.

Family history of cancer and risk of paediatric and young adult's testicular cancer: A Norwegian cohort study.

BACKGROUND: The aim of this study was to examine the association of a family history of cancer with the risk of testicular cancer in young adults. METHODS: This is a prospective cohort study including 1,974,287 males born 1951-2015, of whom 2686 were diagnosed with TC before the age of 30. RESULTS: A history of TC in male relatives was significantly associated with a diagnosis of TC among children and young adults, including brothers (6.3-fold), sons (4.7-fold), fathers (4.4-fold), paternal uncles (2.0-fold) and maternal uncles (1.9-fold). Individuals with a father diagnosed with a carcinoma or sarcoma showed an elevated risk (1.1-fold and 1.8-fold, respectively). A family history of mesothelioma was positively associated with a risk of TC [(father (2.8-fold), mother (4.6-fold) and maternal uncles and aunt (4.4-fold)]. Elevated risks were also observed when siblings were diagnosed with malignant melanoma (1.4-fold). The risk of TC was also increased when fathers (11.1-fold), paternal (4.9-fold) and maternal uncles and aunts (4.6-fold) were diagnosed with malignant neuroepithelial-tumours. CONCLUSION: We found an increased risk of TC among children and young adults with a family history of TC, carcinoma, mesothelioma, sarcoma, malignant melanoma and malignant neuroepithelial tumours. Hereditary cancer syndromes might underlie some of the associations reported in this study.

PTEN Expression in Prostate Cancer: Relationship With Clinicopathologic Features and Multiparametric MRI Findings.

OBJECTIVE. The objective of our study was to investigate whether phosphatase and tensin homolog (PTEN) expression is associated with clinicopathologic features and multiparametric MRI findings in prostate cancer. MATERIALS AND METHODS. Forty-three patients with prostate cancer who underwent radical prostatectomy were included. Index tumor was identified on pretreatment MRI and delineated in the area that correlated best with histopathology results. The apparent diffusion coefficient (ADC) from DWI and pharmacokinetic parameters derived from dynamic contrast-enhanced MRI (DCE-MRI) using the extended Tofts model (Ktrans, kep, ve, and vp) within the tumor were estimated. The following clinicopathologic parameters were assessed: pretreatment serum levels of prostate-specific antigen, disseminated tumor cell status, age, Gleason score, tumor size, extraprostatic extension (EPE), tumor location, and lymph node metastases. Gene expression profiles were acquired in biopsies from the tumor using bead arrays, and validated using reverse transcription quantitative polymerase chain reaction (RT-qPCR) on a different part of the biopsy. RESULTS. Based on bead arrays (p = 0.006) and RT-qPCR (p = 0.03) data, a significantly lower ADC was found in tumors with low PTEN expression. Moreover, PTEN expression was negatively associated with lymph node metastases (bead arrays, p = 0.008; RT-qPCR, p < 0.001). A weak but significant association between PTEN expression, EPE (p = 0.048), and Gleason score (p = 0.028) was revealed on bead arrays. ADC was negatively correlated with Gleason score (p = 0.001) and tumor size (p = 0.023). No association among DCE parameters, PTEN expression, and clinicopathologic features was found. CONCLUSION. ADC derived from DWI may be useful in selecting patients with potentially aggressive tumor caused by PTEN deficiency.

Is time from diagnosis to radical prostatectomy associated with oncological outcomes?

PURPOSE: To study the association between time from diagnosis to radical prostatectomy (RP-interval) and prostate cancer-specific mortality (PCSM), histological findings in the RP-specimen and failure after RP (RP-failure). METHODS: Patients diagnosed with non-metastatic prostate cancer (PCa) in 2001-2010 and prostatectomized within 180 days of biopsy were identified in the Cancer Registry of Norway and the Norwegian Prostate Cancer Registry. Patients were stratified according to risk groups and RP-intervals of 0-60, 61-90, 91-120 and 121-180 days. Aalen-Johansen and Kaplan-Meier methods estimated curves for PCSM, RP-failure and overall mortality. Multivariable Cox regressions and Chi-square tests were used to evaluate the impact of RP-interval on outcomes. RESULTS: In 5163 eligible patients, the median time from diagnosis to RP was 93 days (range 1-180). Risk group distribution was similar in all RP-interval groups. With almost eight years of observation, no association was found between RP-interval and PCSM in the intermediate-or high-risk groups. Increasing RP-interval did not increase the rate of adverse histological outcomes or incidence of RP-failure. CONCLUSIONS: Increasing RP-interval up to 180 days was not associated with adverse oncological outcomes at eight years follow-up. These findings should be considered when planning for prostatectomy.

Combined MR Imaging of Oxygen Consumption and Supply Reveals Tumor Hypoxia and Aggressiveness in Prostate Cancer Patients.

The established role of hypoxia-induced signaling in prostate cancer growth, metastasis, and response to treatment suggests that a method to image hypoxia in tumors could aid treatment decisions. Here, we present consumption and supply-based hypoxia (CSH) imaging, an approach that integrates images related to oxygen consumption and supply into a single image. This integration algorithm was developed in patients with prostate cancer receiving hypoxia marker pimonidazole prior to prostatectomy. We exploited the intravoxel incoherent motion (IVIM) signal in diagnostic diffusion-weighted (DW) magnetic resonance (MR) images to generate separate images of the apparent diffusion coefficient (ADC) and fractional blood volume (fBV). ADC and fBV correlated with cell density (CD) and blood vessel density (BVD) in histology and whole-mount sections from 35 patients, thus linking ADC to oxygen consumption and fBV to oxygen supply. Pixel-wise plots of ADC versus fBV were utilized to predict the hypoxia status of each pixel in a tumor and to visualize the predicted value in a single image. The hypoxic fraction (HFDWI) of CSH images correlated strongly (R2 = 0.66; n = 41) with pimonidazole immunoscore (HSPimo); this relationship was validated in a second pimonidazole cohort (R2 = 0.54; n = 54). We observed good agreement between CSH images and pimonidazole staining in whole-mount sections. HFDWI correlated with tumor stage and lymph node status, consistent with findings for HSPimo Moreover, CSH imaging could be applied on histologic CD and BVD images, demonstrating transferability to a histopathology assay. Thus, CSH represents a robust approach for hypoxia imaging in prostate cancer that could easily be translated into clinical practice.Significance: These findings present a novel imaging strategy that indirectly measures tumor hypoxia and has potential application in a wide variety of solid tumors and other imaging modalities.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/78/16/4774/F1.large.jpg Cancer Res; 78(16); 4774-85. ©2018 AACR.

Chromatin organisation and cancer prognosis: a pan-cancer study.

BACKGROUND: Chromatin organisation affects gene expression and regional mutation frequencies and contributes to carcinogenesis. Aberrant organisation of DNA has been correlated with cancer prognosis in analyses of the chromatin component of tumour cell nuclei using image texture analysis. As yet, the methodology has not been sufficiently validated to permit its clinical application. We aimed to define and validate a novel prognostic biomarker for the automatic detection of heterogeneous chromatin organisation. METHODS: Machine learning algorithms analysed the chromatin organisation in 461 000 images of tumour cell nuclei stained for DNA from 390 patients (discovery cohort) treated for stage I or II colorectal cancer at the Aker University Hospital (Oslo, Norway). The resulting marker of chromatin heterogeneity, termed Nucleotyping, was subsequently independently validated in six patient cohorts: 442 patients with stage I or II colorectal cancer in the Gloucester Colorectal Cancer Study (UK); 391 patients with stage II colorectal cancer in the QUASAR 2 trial; 246 patients with stage I ovarian carcinoma; 354 patients with uterine sarcoma; 307 patients with prostate carcinoma; and 791 patients with endometrial carcinoma. The primary outcome was cancer-specific survival. FINDINGS: In all patient cohorts, patients with chromatin heterogeneous tumours had worse cancer-specific survival than patients with chromatin homogeneous tumours (univariable analysis hazard ratio [HR] 1·7, 95% CI 1·2-2·5, in the discovery cohort; 1·8, 1·0-3·0, in the Gloucester validation cohort; 2·2, 1·1-4·5, in the QUASAR 2 validation cohort; 3·1, 1·9-5·0, in the ovarian carcinoma cohort; 2·5, 1·8-3·4, in the uterine sarcoma cohort; 2·3, 1·2-4·6, in the prostate carcinoma cohort; and 4·3, 2·8-6·8, in the endometrial carcinoma cohort). After adjusting for established prognostic patient characteristics in multivariable analyses, Nucleotyping was prognostic in all cohorts except for the prostate carcinoma cohort (HR 1·7, 95% CI 1·1-2·5, in the discovery cohort; 1·9, 1·1-3·2, in the Gloucester validation cohort; 2·6, 1·2-5·6, in the QUASAR 2 cohort; 1·8, 1·1-3·0, for ovarian carcinoma; 1·6, 1·0-2·4, for uterine sarcoma; 1·43, 0·68-2·99, for prostate carcinoma; and 1·9, 1·1-3·1, for endometrial carcinoma). Chromatin heterogeneity was a significant predictor of cancer-specific survival in microsatellite unstable (HR 2·9, 95% CI 1·0-8·4) and microsatellite stable (1·8, 1·2-2·7) stage II colorectal cancer, but microsatellite instability was not a significant predictor of outcome in chromatin homogeneous (1·3, 0·7-2·4) or chromatin heterogeneous (0·8, 0·3-2·0) stage II colorectal cancer. INTERPRETATION: The consistent prognostic prediction of Nucleotyping in different biological and technical circumstances suggests that the marker of chromatin heterogeneity can be reliably assessed in routine clinical practice and could be used to objectively assist decision making in a range of clinical settings. An immediate application would be to identify high-risk patients with stage II colorectal cancer who might have greater absolute benefit from adjuvant chemotherapy. Clinical trials are warranted to evaluate the survival benefit and cost-effectiveness of using Nucleotyping to guide treatment decisions in multiple clinical settings. FUNDING: The Research Council of Norway, the South-Eastern Norway Regional Health Authority, the National Institute for Health Research, and the Wellcome Trust.

Comparison of time curves from dynamic 18F-fluciclovine positron emission tomography and dynamic contrast-enhanced magnetic resonance imaging for primary prostate carcinomas.

BACKGROUND AND PURPOSE: Multimodal imaging is increasingly included in the assessment of prostate cancer patients, and there is a need to study whether different techniques provide similar or complementary information. In the initial perfusion phase contrast agents and radioactive labelled tracers act as blood-pool agents and may show similar characteristics. The purpose of the current work was to compare time-activity- and time-concentration-curves (TCs) of dynamic 18F-fluciclovine (18F-anti-1-amino-2-[F]-fluorocyclobutane-1-carboxylic acid, FACBC) positron emission tomography (PET) and dynamic contrast-enhanced magnetic resonance imaging (DCE MRI). MATERIALS AND METHODS: Dynamic FACBC PET and DCE MRI were performed on 22 patients with intermediate or high-risk prostate cancer within 23 days prior to robot-assisted laparoscopic prostatectomy. Index tumour was delineated in the images using whole mount tissue sections as reference standard. Tumour TCs from PET and MRI were compared visually and quantitatively by calculating correlation coefficients between the curves at different time points after injection. RESULTS: For the first minute post injection, the mean correlation coefficient between the TCs from PET and MRI was 0.92 (range; 0.75-0.99). After the first minute, MRI showed washout while PET showed plateau kinetics. CONCLUSION: Dynamic FACBC and DCE MRI showed similar wash-in time curve characteristics. At later time points, FACBC plateaued whereas MR contrast medium washed out. In DCE MRI, the usefulness of wash-in information is well documented. Whether wash-in information from dynamic FACBC can provide added value remains to be documented.

Tumour heterogeneity poses a significant challenge to cancer biomarker research.

BACKGROUND: The high degree of genomic diversity in cancer represents a challenge for identifying objective prognostic markers. We aimed to examine the extent of tumour heterogeneity and its effect on the evaluation of a selected prognostic marker using prostate cancer as a model. METHODS: We assessed Gleason Score (GS), DNA ploidy status and phosphatase and tensin homologue (PTEN) expression in radical prostatectomy specimens (RP) from 304 patients followed for a median of 10 years (interquartile range 6-12). GS was assessed for every tumour-containing block and DNA ploidy for a median of four samples for each RP. In a subgroup of 40 patients we assessed DNA ploidy and PTEN status in every tumour-containing block. In 102 patients assigned to active surveillance (AS), GS and DNA ploidy were studied in needle biopsies. RESULTS: Extensive heterogeneity was observed for GS (89% of the patients) and DNA ploidy (40% of the patients) in the cohort, and DNA ploidy (60% of the patients) and PTEN expression (75% of the patients) in the subgroup. DNA ploidy was a significant prognostic marker when heterogeneity was taken into consideration. In the AS cohort we found heterogeneity in GS (24%) and in DNA ploidy (25%) specimens. CONCLUSIONS: Multi-sample analysis should be performed to support clinical treatment decisions.

Phase I/IIa clinical trial of a novel hTERT peptide vaccine in men with metastatic hormone-naive prostate cancer.

In newly diagnosed metastatic hormone-naive prostate cancer (mPC), telomerase-based immunotherapy with the novel hTERT peptide vaccine UV1 can induce immune responses with potential clinical benefit. This phase I dose escalation study of UV1 evaluated safety, immune response, effects on prostate-specific antigen (PSA) levels, and preliminary clinical outcome. Twenty-two patients with newly diagnosed metastatic hormone-naïve PC (mPC) were enrolled; all had started androgen deprivation therapy and had no visceral metastases. Bone metastases were present in 17 (77%) patients and 16 (73%) patients had affected lymph nodes. Three dose levels of UV1 were given as intradermal injections combined with GM-CSF (Leukine®). Twenty-one patients in the intention-to-treat population (95%) received conformal radiotherapy. Adverse events reported were predominantly grade 1, most frequently injection site pruritus (86.4%). Serious adverse events considered possibly related to UV1 and/or GM-CSF included anaphylactic reaction in two patients and thrombocytopenia in one patient. Immune responses against UV1 peptides were confirmed in 18/21 evaluable patients (85.7%), PSA declined to <0.5 ng/mL in 14 (64%) patients and in ten patients (45%) no evidence of persisting tumour was seen on MRI in the prostatic gland. At the end of the nine-month reporting period for the study, 17 patients had clinically stable disease. Treatment with UV1 and GM-CSF gave few adverse events and induced specific immune responses in a large proportion of patients unselected for HLA type. The intermediate dose of 0.3 mg UV1 resulted in the highest proportion of, and most rapid UV1-specific immune responses with an acceptable safety profile. These results warrant further clinical studies in mPC.