Search

Rationale and objectives Prostate MRI improves detection of clinically significant prostate cancer; however, its diagnostic performance has wide variation. Artificial intelligence (AI) has the potential to assist radiologists in the detection and classification of prostatic lesions. Herein, we aimed to develop and test a cascaded deep learning detection and classification system trained on biparametric prostate MRI using PI-RADS for assisting radiologists during prostate MRI read out. Materials and Methods T2-weighted, diffusion-weighted (ADC maps, high b value DWI) MRI scans obtained at 3 Tesla from two institutions (n = 1043 in-house and n = 347 Prostate-X, respectively) acquired between 2015 to 2019 were used for model training, validation, testing. All scans were retrospectively reevaluated by one radiologist. Suspicious lesions were contoured and assigned a PI-RADS category. A 3D U-Net-based deep neural network was used to train an algorithm for automated detection and segmentation of prostate MRI lesions. Two 3D residual neural network were used for a 4-class classification task to predict PI-RADS categories 2 to 5 and BPH. Training and validation used 89% (n = 1290 scans) of the data using 5 fold cross-validation, the remaining 11% (n = 150 scans) were used for independent testing. Algorithm performance at lesion level was assessed using sensitivities, positive predictive values (PPV), false discovery rates (FDR), classification accuracy, Dice similarity coefficient (DSC). Additional analysis was conducted to compare AI algorithm's lesion detection performance with targeted biopsy results. Results Median age was 66 years (IQR = 60-71), PSA 6.7 ng/ml (IQR = 4.7-9.9) from in-house cohort. In the independent test set, algorithm correctly detected 111 of 198 lesions leading to 56.1% (49.3%-62.6%) sensitivity. PPV was 62.7% (95% CI 54.7%-70.7%) with FDR of 37.3% (95% CI 29.3%-45.3%). Of 79 true positive lesions, 82.3% were tumor positive at targeted biopsy, whereas of 57 false negative lesions, 50.9% were benign at targeted biopsy. Median DSC for lesion segmentation was 0.359. Overall PI-RADS classification accuracy was 30.8% (95% CI 24.6%-37.8%). Conclusion Our cascaded U-Net, residual network architecture can detect, classify cancer suspicious lesions at prostate MRI with good detection, reasonable classification performance metrics.

Upfront knowledge of tumor growth rates of clear cell renal cell carcinoma in von Hippel-Lindau syndrome (VHL) patients can allow for a more personalized approach to either surveillance imaging frequency or surgical planning. In this study, we implement a machine learning algorithm utilizing radiomic features of renal tumors identified on baseline magnetic resonance imaging (MRI) in VHL patients to predict the volumetric growth rate category of these tumors.A total of 73 VHL patients with 173 pathologically confirmed Clear Cell Renal Cell Carcinoma (ccRCCs) underwent MRI at least at two different time points between 2015 and 2021. Each tumor was manually segmented in excretory phase contrast T1 weighed MRI and co-registered on pre-contrast, corticomedullary and nephrographic phases. Radiomic features and volumetric data from each tumor were extracted using the PyRadiomics library in Python (4544 total features). Tumor doubling time (DT) was calculated and patients were divided into two groups: DT = 1 year and DT 1 year. Random forest classifier (RFC) was used to predict the DT category. To measure prediction performance, the cohort was randomly divided into 100 training and test sets (80% and 20%). Model performance was evaluated using area under curve of receiver operating characteristic curve (AUC-ROC), as well as accuracy, F1, precision and recall, reported as percentages with 95% confidence intervals (CIs).The average age of patients was 47.2 ± 10.3 years. Mean interval between MRIs for each patient was 1.3 years. Tumors included in this study were categorized into 155 Grade 2; 16 Grade 3; and 2 Grade 4. Mean accuracy of RFC model was 79.0% [67.4-90.6] and mean AUC-ROC of 0.795 [0.608-0.988]. The accuracy for predicting DT classes was not different among the MRI sequences (P-value = 0.56).Here we demonstrate the utility of machine learning in accurately predicting the renal tumor growth rate category of VHL patients based on radiomic features extracted from different T1-weighted pre- and post-contrast MRI sequences.

OBJECTIVE: To evaluate whether bilateral, multifocal clear cell renal cell carcinoma (ccRCC) patients can be differentiated by VHL mutation analysis into cases that represent either multiple independently arising primary tumors, or a single primary tumor which has spread ipsilaterally as well as to the contralateral kidney. The nature of kidney cancer multifocality outside of known hereditary syndromes is as yet poorly understood. MATERIALS AND METHODS: DNA from multiple tumors per patient were evaluated for somatic VHL gene mutation and hypermethylation. A subset of tumors with shared VHL mutations were analyzed with targeted, next-generation sequencing assays. RESULTS: This cohort contained 5 patients with multiple tumors that demonstrated a shared somatic VHL mutation consistent with metastatic spread including to the contralateral kidney. In several cases this was substantiated by additional shared somatic mutations in ccRCC-associated genes. In contrast, the remaining 14 patients with multiple tumors demonstrated unique, unshared VHL alterations in every analyzed tumor, consistent with independently arising kidney tumors. None of these latter patients showed any evidence of local spread or distant metastasis. CONCLUSION: The spectrum of VHL alterations within evaluated bilateral, multifocal ccRCC tumors from a single patient can distinguish between multiple independent tumor growth and metastasis. This can be performed using currently available clinical genetic tests and will improve the accuracy of patient diagnosis and prognosis, as well as informing appropriate management.

PDF file - 233K, VHL mutation status in some but not all tumors from Family NCI-1326.

PDF file - 104K

Legends for all included Supplementary Figures

Heat map of cell cycle gene expression. Gene expression was normalized and compared between the primary MTC, metastasis one, and metastasis two lesions from the whole transcriptome RNA-seq data. Purple indicates lower and yellow indicates higher expression. Values to generate colors are z-scores across each genes' relative transcript levels [log2(FPKM)].

Purpose: The goal of this study was to comprehensively define the incidence of mutations in all exons of PIK3CA in both endometrioid endometrial cancer (EEC) and nonendometrioid endometrial cancer (NEEC).Experimental Design: We resequenced all coding exons of PIK3CA and PTEN, and exons 1 and 2 of KRAS, from 108 primary endometrial tumors. Somatic mutations were confirmed by sequencing matched normal DNAs. The biochemical properties of a subset of novel PIK3CA mutations were determined by exogenously expressing wild type and mutant constructs in U2OS cells and measuring levels of AKTSer473 phosphorylation.Results: Somatic PIK3CA mutations were detected in 52.4% of 42 EECs and 33.3% of 66 NEECs. Half (29 of 58) of all nonsynonymous PIK3CA mutations were in exons 1–7 and half were in exons 9 and 20. The exons 1–7 mutations localized to the ABD, ABD-RBD linker and C2 domains of p110α. Within these regions, Arg88, Arg93, Gly106, Lys111, Glu365, and Glu453, were recurrently mutated; Arg88, Arg93, and Lys111 formed mutation hotspots. The p110α-R93W, -G106R, -G106V, -K111E, -delP449-L455, and -E453K mutants led to increased levels of phospho-AKTSer473 compared to wild-type p110α. Overall, 62% of exons 1–7 PIK3CA mutants and 64% of exons 9–20 PIK3CA mutants were activating; 72% of exon 1–7 mutations have not previously been reported in endometrial cancer.Conclusions: Our study identified a new subgroup of endometrial cancer patients with activating mutations in the amino-terminal domains of p110α; these patients might be appropriate for consideration in clinical trials of targeted therapies directed against the PI3K pathway. Clin Cancer Res; 17(6); 1331–40. ©2011 AACR.

Weight-for-age and height-for-age growth curves. Male patient weights (A), heights (B) and female patient weights (C), and heights (D) were monitored during the follow up period. Patient weight-for-age and height-for-age values were compared to U.S. Center for Disease Control reference growth curves.

Doubling time of calcitonin and CEA for patient #12 was suggestive of progressive disease. Patient #12 experienced best response 434 days after starting vandetanib, with stable lesions in the thyroid bed (showed on T2-weighted MRI of the neck, A) and the mediastinum (showed on CT of the chest, B). In August 2016, the sum of longest diameter (per RECIST) of target lesions was consistent with SD (C,D) (note that not all target lesions are shown). Biomarker response in the two years prior (E) showed CEA doubling time 1.2 years (F) and calcitonin doubling time 1.67 years (G). Patient #12 was confirmed to have PD via RECIST February 2017.

Purpose:For high-risk prostate cancer, standard treatment options include radical prostatectomy (RP) or radiotherapy plus androgen deprivation therapy (ADT). Despite definitive therapy, many patients will have disease recurrence. Imaging has the potential to better define characteristics of response and resistance. In this study, we evaluated prostate multiparametric MRI (mpMRI) before and after neoadjuvant enzalutamide plus ADT.Patients and Methods:Men with localized intermediate- or high-risk prostate cancer underwent a baseline mpMRI and mpMRI-targeted biopsy followed by a second mpMRI after 6 months of enzalutamide and ADT prior to RP. Specimens were sectioned in the same plane as mpMRI using patient-specific 3D-printed molds to permit mpMRI-targeted biopsies to be compared with the same lesion from the RP. Specimens were analyzed for imaging and histologic correlates of response.Results:Of 39 patients enrolled, 36 completed imaging and RP. Most patients (92%) had high-risk disease. Fifty-eight lesions were detected on baseline mpMRI, of which 40 (69%) remained measurable at 6-month follow-up imaging. Fifty-five of 59 lesions (93%) demonstrated >50% volume reduction on posttreatment mpMRI. Three of 59 lesions (5%) demonstrated growth in size at follow-up imaging, with two lesions increasing more than 3-fold in volume. On whole-mount pathology, 15 patients demonstrated minimal residual disease (MRD) of Conclusions:Low relative lesion volume at baseline mpMRI was predictive of pathologic response. A subset of patients had limited response. Selection of patients based on these metrics may improve outcomes in high-risk disease.

Purpose: Vandetanib is well-tolerated in patients with advanced medullary thyroid carcinoma (MTC). Long-term outcomes and mechanisms of MTC progression have not been reported previously.Experimental Design: We monitored toxicities and disease status in patients taking vandetanib for hereditary, advanced MTC. Tumor samples were analyzed for molecular mechanisms of disease progression.Results: Seventeen patients [8 male, age 13 (9–17)* years] enrolled; 16 had a RET p.Met918Thr germline mutation. The duration of vandetanib therapy was 6.1 (0.1–9.7+)* years with treatment ongoing in 9 patients. Best response was partial response in 10, stable disease in 6, and progressive disease in one patient. Duration of response was 7.4 (0.6–8.7+)* and 4.9 (0.6–7.8+)* years in patients with PR and SD, respectively. Six patients died 2.0 (0.4–5.7)* years after progression. Median progression-free survival (PFS) was 6.7 years [95% confidence interval (CI): 2.3 years–undefined] and 5-year overall survival (OS) was 88.2% (95% CI: 60.6%–96.9%). Of 16 patients with a RET p.Met918Thr mutation, progression-free survival was 6.7 years (95% CI: 3.1–undefined) and 5-year overall survival was 93.8% (95% CI: 63.2%–99.1%). No patients terminated treatment because of toxicity. DNA sequencing of tissue samples (n = 11) identified an increase in copy number alterations across the genome as a potential mechanism of drug resistance [*median (range)].Conclusions: This study demonstrates that vandetanib is safe and results in sustained responses in children and adolescents with hereditary MTC. Our preliminary molecular data suggest that an increase in copy number abnormalities may be associated with tumor progression in hereditary MTC patients treated with vandetanib. Clin Cancer Res; 24(4); 753–65. ©2017 AACR.

Purpose: Medullary thyroid carcinoma (MTC) is a manifestation of multiple endocrine neoplasia type 2 (MEN2) syndromes caused by germline, activating mutations in the RET (REarranged during Transfection) proto-oncogene. Vandetanib, a VEGF and EGF receptor inhibitor, blocks RET tyrosine kinase activity and is active in adults with hereditary MTC.Experimental Design: We conducted a phase I/II trial of vandetanib for children (5–12 years) and adolescents (13–18 years) with MTC to define a recommended dose and assess antitumor activity. The starting dose was 100 mg/m2 administered orally, once daily, continuously for 28-day treatment cycles. The dose could be escalated to 150 mg/m2/d after two cycles. Radiographic response to vandetanib was quantified using RECIST (v1.0), biomarker response was measured by comparing posttreatment serum calcitonin and carcinoembryonic antigen (CEA) levels to baseline, and a patient-reported outcome was used to assess clinical benefit.Results: Sixteen patients with locally advanced or metastatic MTC received vandetanib for a median (range) 27 (2–52) cycles. Eleven patients remain on protocol therapy. Diarrhea was the primary dose-limiting toxicity. In subjects with M918T RET germline mutations (n = 15) the confirmed objective partial response rate was 47% (exact 95% confidence intervals, 21%–75%). Biomarker partial response was confirmed for calcitonin in 12 subjects and for CEA in 8 subjects.Conclusion: Using an innovative trial design and selecting patients based on target gene expression, we conclude that vandetanib 100 mg/m2/d is a well-tolerated and highly active new treatment for children and adolescents with MEN2B and locally advanced or metastatic MTC. Clin Cancer Res; 19(15); 4239–48. ©2013 AACR.

Supplementary Figure S1; Supplementary Tables S1-S5.

PDF file - 67K

Contains supplementary methods and 3 supplementary tables.

Doubling time of calcitonin and CEA during vandetanib therapy. Calcitonin and CEA slopes and doubling times were calculated from the change during the initial four months of vandetanib (A,B), from values the year before experiencing PD or the data cutoff (C,D) and in patients that experienced progressive disease (E).

Patients #2, #5, #10, #11, #13, #15, and #16 experienced durable SD or PR during the follow up period. Calcitonin and CEA are shown as percent change from baseline at the start of vandetanib therapy (left y-axis). Tumor size is the sum of longest diameter of lesions per RECISTv1.0 (right y-axis).

Nm23-H1 transcriptionally down-regulates expression of the lysophosphatidic acid receptor EDG2 and this down-regulation is critical for Nm23-H1–mediated motility suppression in vitro. We investigated the effect of altered EDG2 expression on Nm23-H1–mediated metastasis suppression in vivo. Clonal MDA-MB-435–derived tumor cell lines transfected with Nm23-H1 together with either a vector control or EDG2 had similar anchorage-dependent and anchorage-independent growth rates in vitro. However, a 45- and 300-fold inhibition of motility and invasion (P < 0.0001), respectively, was observed in Nm23-H1/vector lines, whereas coexpression of EDG2 restored activity to levels observed in the parental line. Using fluorescently labeled cells and ex vivo microscopy, the capacity of these cells to adhere, arrest, extravasate, and survive in the murine lung over a 24-h time course was measured. Only 5% of Nm23-H1/vector–transfected cells were retained in the murine lung 6 h following tail vein injection; coexpression of EDG2 enhanced retention 8- to 13-fold (P < 0.01). In a spontaneous metastasis assay, the primary tumor size of Nm23-H1/vector and Nm23-H1/EDG2 clones was not significantly different. However, restoration of EDG2 expression augmented the incidence of pulmonary metastasis from 51.9% to 90.4% (P = 2.4 × 10−5), comparable with parental MDA-MB-435 cells. To determine the relevance of this model system to human breast cancer, a cohort of breast carcinomas was stained for Nm23-H1 and EDG2 and a statistically significant inverse correlation between these two proteins was revealed (r = −0.73; P = 0.004). The data indicate that Nm23-H1 down-regulation of EDG2 is functionally important to suppression of tumor metastasis. [Cancer Res 2007;67(24):11751–9]

Supplementary Table 1, Figure Legend from Nm23-H1 Suppresses Metastasis by Inhibiting Expression of the Lysophosphatidic Acid Receptor EDG2

Supplementary Figure 1 from Nm23-H1 Suppresses Metastasis by Inhibiting Expression of the Lysophosphatidic Acid Receptor EDG2

PURPOSE: Multiple studies demonstrate MRI-targeted biopsy detects more clinically significant cancer than systematic biopsy, however some clinically significant cancers are detected by systematic biopsy only. While these events are rare, we sought to perform a retrospective analysis of these cases to ascertain the reasons that MRI-targeted biopsy missed clinically significant cancer, which was subsequently detected on systematic prostate biopsy. METHODS: Patients were enrolled in a prospective study comparing cancer detection rates by transrectal MRI-targeted fusion biopsy and systematic 12-core biopsy. Patients with an elevated PSA, abnormal digital rectal exam, or imaging findings concerning for prostate cancer underwent prostate MRI and subsequent MRI-targeted and systematic biopsy in the same setting. The subset of patients with grade group (GG) ≥3 cancer found on systematic biopsy and GG≤2 cancer (or no cancer) on MRI-targeted biopsy were classified as MRI-targeted biopsy misses. A retrospective analysis of the MRI and MRI-targeted biopsy real-time screen captures determined the cause of MRI-targeted biopsy miss. Multivariable logistic regression analysis compared baseline characteristics of patients with MRI-targeted biopsy misses to GG-matched patients whose clinically significant cancer was detected by MRI-targeted biopsy. RESULTS: Over the study period of 2007 to 2019, 2103 patients met study inclusion criteria and underwent combined MRI-targeted and systematic prostate biopsies. 41 (1.9%) men were classified as MRI-targeted biopsy misses. Most MRI-targeted biopsy misses were due to errors in lesion targeting (n=21, 51.2%), followed by MRI-invisible lesions (n=17, 40.5%), and MRI lesions missed by the radiologist (n=3, 7.1%). On logistic regression analysis, lower PI-RADS score was associated with having clinically significant cancer missed on MRI-targeted biopsy. CONCLUSION: While uncommon, most MRI-targeted biopsy misses are due to errors in lesions targeting, which highlights the importance of accurate co-registration and targeting when using software-based fusion platforms. Additionally, some patients will harbor MRI-invisible lesions which are un-targetable by MRI-targeted platforms. The presence of a low PI-RADS score despite a high PSA is suggestive of harboring an MRI-invisible lesion.

We report a series of four unrelated adults with Smith-Magenis syndrome (SMS) and concomitant features of Birt-Hogg-Dubé (BHD) syndrome based upon haploinsufficiency for FLCN and characteristic renal cell carcinomas and/or evidence of cutaneous fibrofolliculomas. Three of the cases constitute the first known association of histopathologically verified characteristic BHD-associated renal tumors in adults with SMS; the fourth was identified to have histologically confirmed skin fibrofolliculomas. Molecular analysis documented second-hit FLCN mutations in two of the three cases with confirmed BHD renal pathology. These cases suggest the need to expand management recommendations for SMS to include kidney cancer surveillance starting at 20 years of age, as per the screening recommendations for BHD syndrome.

PurposeThe aim of this work is to assess the feasibility of novel targeted methods for fresh tissue procurement that facilitate accurate identification of lesion location and tissue sample extraction in an excised prostate gland, while minimizing the tissue deformation or damage.Methods and ResultsProposed fresh tissue procurement methods are based on utilizing a custom 3D printed patient-specific prostate mold. In the semi-freehand method, the access cut is guided by a set of markers on the bottom of the mold that define the boundary of a lesion in two orthogonal directions. The procurement site is identified by palpation. In the guided cut with-locator card method the procurement sites are identified by a cutout in the locator cards inserted into the access cuts. The two approaches were utilized to procure >50 samples. In the biopsy needle method guiding channels were designed into the prostate mold to procure fresh tissue. This method was used 4 times. Finally, a mixed-reality biopsy needle method was developed for phantom testing.ConclusionsPreliminary results of fresh tissue procurement utilizing novel methods showed improve precision of obtaining cancerous fresh tissue for molecular and genomic cancer research compared to current methods which rely on surgical estimation of lesion location.

Background: Renal cell carcinomas developing in patients with HLRCC syndrome are known to be aggressive single tumors of variable sizes, with a well-established morphology. Other morphological tumor types occurring in association with classic HLRCC tumors as independent neoplasias in this syndrome, have not been clearly recognized and described. We describe four patients with known HLRCC syndrome with confirmed germ line mutation who developed benign oncocytic renal tumors. Since HLRCC can also be oncocytic in many instances, it is important to be aware of the possible benign oncocytic tumors in this patient group. Design: Four patients with known positive germ line FH mutation and known HLRCC syndrome developed associated or new oncocytic tumors. All tumors were morphologically evaluated, IHC staining was done for FH, 2SC, CKIT, CK7, PAX8 and molecular studies were performed with TSO-500 for the evaluation of other genes. Clinicopathological correlation was done in all cases. Results: The tumors had been identified radiologically and were suspicious for malignancy. Age range was 37-73 years, and all the patients were female. Two patients had coexistent HLRCC cancers while two only had the oncocytomas. Localization was left kidney for all the masses, which were brown in color and well circumscribed and varied in size from 0.7 to 4 cm. In one patient, four separate masses were identified with different locations and sizes, but with the same morphology. This specific patient presented with two additional masses in the opposite kidney later. Tumors were composed of large oncocytic cells with prominent granular eosinophilic cytoplasm and dark pyknotic nuclei. No evidence of atypia, mitosis or necrosis was found. FH was positive, 2SC and CK7 were negative on IHC stains, whereas CKIT showed diffuse membranous positivity. Tumors were diagnosed as oncocytomas. All patients were positive for FH germ line mutation and the mutation was also identified in the tissues. Other molecular studies on the patient with multiple tumors showed additional pathogenic ERCC2 inactivating mutation, suggesting germline, which is rarely encountered in kidney tumors. All the patients are alive and free of disease up to 10 years after diagnosis. Conclusion: HLRCC cancers can have a variety of morphologic patterns and frequently have oncocytic features. Clinical information, genetic testing and special techniques are helpful in the diagnosis of these high-grade tumors. Recognizing that other benign indolent tumors with oncocytic features can occur in this syndrome is important to avoid errors in diagnosis and treatment. Citation Format: Dilara Akbulut, Mark Ball, Mark Raffeld, Marston Linehan, Maria J. Merino. Benign oncocytic tumors in the setting of HLRCC syndrome [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1518.

390 Background: PCa has inherited risk factors including high genetic risk variants such as BRCA1/2, HOXB13, and DNA mismatch repair genes. mpMRI has been shown to be effective for detection and staging of localized PCa. This study follows participants (prts), born biologically male, without a diagnosis of PCa with known germline pathogenic or likely pathogenic variants (PV) in BRCA1/2, MLH1, MSH2, MSH6, PMS2, EPCAM, HOXB13, ATM, NBN, TP53, CHEK2, PALB2, RAD51C/D, BRIP1, or FANCA-FANCM (NCT03805919). Methods: Up to 500 eligible prts 30-75 years old (yo) with a documented germline PV will enroll. Prts undergo biennial clinical exam and mpMRI, and annual PSA monitoring and are followed at 12-month intervals to determine PSA, prostate cancer diagnosis, and/or disease/survival status until death. Indication for prostate biopsy includes clinical or imaging findings. Biopsy specimens undergo molecular analyses. Results: To date, 175 prts have been enrolled: 169 (97%) White, 3 Hispanic (2%), 1 African American (1%), 1 Asian (1%), and 1 biethnic (1%). Median age is 47 yo. The most common monoallelic PV are: 48.6% BRCA2, 25.1% BRCA1, 6.3% CHEK2 and 5.7% MSH2. PVs in ATM, PALB2, HOXB13, PMS2, MLH1, MSH6, BRIP1, EPCAM and RAD51D are ≤4%. One subject carries three distinct PVs ( BRCA2, CHEK2, BRIP1). Indication for biopsy was found in 26.3% of prts with 22/46 (47.8%) with a PIRADS 4 lesion, 6/46 (13.0%) PIRADS 3 lesion, 12/46 (26.1%) elevated PSA (median=2.8 ng/mL) or 6/46 (13.0%) due to clinical discretion. Adenocarcinoma was diagnosed on 13/39 (33.3%) biopsies with median age at diagnosis=59 yo. 9/13 (69%) prts had a PSA

The underlying premise of prostate cancer active surveillance (AS) is that cancers likely to metastasize will be recognized and eliminated before cancer-related disease can ensue. Our study was designed to determine the prostate cancer upgrading rate when biopsy guided by magnetic resonance imaging (MRGBx) is used before entry and during AS.The cohort included 519 men with low- or intermediate-risk prostate cancer who enrolled in prospective studies (NCT00949819 and NCT00102544) between February 2008 and February 2020. Subjects were preliminarily diagnosed with Gleason Grade Group (GG) 1 cancer; AS began when subsequent MRGBx confirmed GG1 or GG2. Participants underwent confirmatory MRGBx (targeted and systematic) followed by surveillance MRGBx approximately every 12 to 24 months. The primary outcome was tumor upgrading to ≥GG3.Upgrading to ≥GG3 was found in 92 men after a median followup of 4.8 years (IQR 3.1-6.5) after confirmatory MRGBx. Upgrade-free probability after 5 years was 0.85 (95% CI 0.81-0.88). Cancer detected in a magnetic resonance imaging lesion at confirmatory MRGBx increased risk of subsequent upgrading during AS (HR 2.8; 95% CI 1.3-6.0), as did presence of GG2 (HR 2.9; 95% CI 1.1-8.2) In men who upgraded ≥GG3 during AS, upgrading was detected by targeted cores only in 27%, systematic cores only in 25% and both in 47%. In 63 men undergoing prostatectomy, upgrading from MRGBx was found in only 5 (8%).When AS begins and follows with MRGBx (targeted and systematic), upgrading rate (≥GG3) is greater when tumor is initially present within a magnetic resonance imaging lesion or when pathology is GG2 than when these features are absent.

Introduction: Intravesical Bacillus Calmette-Guerin (BCG) is an effective immunotherapy for non-muscle invasive bladder cancer (NMIBC). However, BCG treatment failure will lead to recurrence and tumor progression. In this study, urinary exosomes content (miRNA profile) was evaluated as a possible marker of BCG treatment response in NMIBC patients. Methods: Urine samples from patients with bladder cancer were collected at the time of surgery and during patient follow up to 1 year. Urine from healthy volunteers were also included. Clinical and pathological information such as tumor grade (High Grade (HG), Low Grade (LG)), depth of invasion (Ta, T1, CIS), and response to BCG treatment was also obtained. Exosome Isolation and total RNA extraction including microRNAs from cell-free urine after centrifugation were obtained. Library preparation for miRNA expression was done (QIAseq® miRNA Library) for Next-Generation Sequencing (NGS) analysis in a NextSeq 2000 single read platform, 75 bp with 15-20 million reads per sample. Reads were then queried against miRDeep2 software for identification. Only miRNAs having at least 20 counts considering all samples were included. After normalization, significantly and deferentially expressed microRNAs (>2-Fold) were selected for analysis. Bioinformatic analysis including sequence alignment was performed under the STAR-based approach. Identified microRNAs were then used to classify/predict the response to treatment and its relationship with other clinicopathologic variables. Results: A total of 56 urine samples from 13 patients were available/used for analysis including 10 High Grade Ta and 3 High Grade T1 patients. Urine from normal healthy donors (N=3) was also included. Clinicopathological features were patients with HGTa=10, HGT1=3 and 3 control samples. Regarding treatment response 9 patients were BCG responders and 4 BCG unresponsive. When compared to BCG unresponsive patients, BCG responders showed 45 differentially expressed miRNAs. Statistically significant differentially expressed miRNAs (Fold-change >2, p value Conclusion: Our study supports the value of urinary exosomal microRNAs as non-invasive biomarkers to predict BCG treatment response in nonmuscle-invasive bladder cancer. Citation Format: Vladimir Valera, Beatriz Walter, Maria J. Merino. Urinary exosome analysis as a marker of treatment response in bladder cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5831.

Purpose Men with intermediate risk (IR) prostate cancer (CaP) are often excluded from active surveillance (AS) due to higher rates of adverse pathology (AP). We determined our rate of AP in men who underwent multiparametric MRI (MpMRI) with combined biopsy (CB) consisting of targeted biopsy (TB) and systematic biopsy (SB) prior to radical prostatectomy (RP). Methods A retrospective review was conducted of men with Gleason Grade Group (GG) 2 disease who underwent RP after SB alone or after preoperative MRI with CB. AP was defined as either pathologic stage T3a (AP ≥ T3a) or pathologic stage T3b (AP ≥ T3b) and/or GG upgrading. Rates of AP were determined for both groups and those who fit the National Comprehensive Cancer Network (NCCN) definition of favorable IR (FIR) or the low volume IR (LVIR) criteria. Multivariable logistic regression was used to determine predictive factors. Results The overall rate of AP ≥ T3b was 21.2% in the SB group vs. 8.6% in the MRI with CB group, P = 0.006. This rate was lowered to 6.8% and 5.6% when men met the definition of NCCN FIR or LVIR, respectively. Suspicion for extraprostatic extension (EPE) (OR 7.65, 95% CI 1.77−33.09, P = 0.006) and positive cores of GG 2 on SB (OR 1.43, 95% CI 1.05−1.96, P = 0.023) were significant for predicting AP ≥ T3b. Conclusions Rates of AP at RP after MRI with CB are lower than studies prior to the adoption of this technology, suggesting that more men with IR disease may be considered for AS. However, increasing cores positive on SB and MRI findings suggestive of EPE remain unsafe.