Faculty Bibliography

PURPOSE/OBJECTIVE:To determine whether multi-parametric magnetic resonance imaging (mpMRI) can reliably predict proximity of prostate cancer to the prostatic urethra in a contemporary series of men undergoing radical prostatectomy (RP) at two academic centers. METHODS:Clinical characteristics of consecutive men undergoing pre-operative mpMRI prior to RP and whole-mount axial serial step-sectioned pathology examination at two academic centers between Jun 2016 and Oct 2018 were analyzed retrospectively. Every tumor was characterized by its pathologic minimum distance to the prostatic urethral lumen (pMDUL). Only the cancer closest to the urethra represented the prostatic urethral index lesion. The radiologic minimum distance of the index lesion to the prostatic urethral lumen was measured and noted as ≤ 5 mm versus  > 5 mm. The sensitivity, specificity, positive and negative predicting values (PPV and NPV) and area under the receivers operating characteristics curve (AUC) were calculated for performance of mpMRI for predicting pMDUL ≤ 5 mm. RESULTS:Of the 163 surgical specimens examined, 112 (69%) exhibited a pMDUL ≤ 5 mm. These men had significantly higher grade group (GG) and advanced pathological and clinical stage. The rates of high PI-RADS score and presence of gross extracapsular extension were also significantly greater for the group with pMDUL ≤ 5 mm. The AUC, sensitivity, specificity, PPV, and NPV were 0.641, 51.8, 76.5, 82.9, and 42.4%, respectively, for mpMRI to predict pMDUL < 5 mm. CONCLUSIONS:Nearly 70% of men undergoing RP present with tumor within 5 mm of the prostatic urethra. These tumors present higher risk characteristics, and mpMRI exhibited moderate performance and high PPV in their pre-operative detection. Physicians performing partial gland ablation should take these results into consideration during treatment selection and planning.

Gastric cancer is a rare long-term complication in gastrocystoplasty. We report 2 cases of gastric adenocarcinoma and review the literature for similar cases. A total of 14 cases are identified. The majority of patients are males, presented with hematuria, and developed cancer at a younger age, more than 10 years after gastrocystoplasty. Long-term follow up information was limited, but 5 patients (36%) died within 5 years of diagnosis. Annual surveillance for malignancy may not be effective due to its rarity. However, symptomatic patients, particularly those 10 years after the surgery, warrant detailed evaluation to rule out neoplastic transformation.

PURPOSE/OBJECTIVE:A benign MRI-targeted prostate biopsy (MRF-TB) in the setting of a PI-RADS 4/5 abnormality presents a clinical dilemma for future management. We evaluated benign histologic features on MRF-TB to determine if they predict the likelihood of missed cancer on subsequent biopsy. MATERIALS AND METHODS/METHODS:Between 6/2012 and 9/2016, 1595 men were enrolled in a prospective study of MRI-targeted and systematic biopsy outcomes. We re-reviewed pathology from benign MRF-TB of PI-RADS 4/5 abnormalities and divided into 5 groups for comparison to outcomes of clinical follow-up: inflammation (38%), stroma/glandular hyperplasia (9%), normal prostate tissue (28%), ASAP/HGPIN (9%), and cancer in adjacent systematic cores (16%). RESULTS:88/497 (18%) men with PI-RADS 4/5 abnormality prior to initial biopsy had no cancer on MRF-TB. In follow-up, 45 men underwent repeat MRI: 12 (27%) had persistent PI-RADS 4/5 abnormalities, 17 (38%) had PI-RADS 2/3, 16 (35%) had PI-RADS 1. On repeat MRF-TB, cancer was found in 62.5% of men with PI-RADS 4/5 and 23% of men with PI-RADS 2/3. Histologic groups on initial MRF-TB were not predictive of the likelihood of PI-RADS downgrade on repeat MRI or cancer detection on repeat biopsy. CONCLUSIONS:Among men with no cancer on MRF-TB performed for PI-RADS abnormality, downgrade of PI-RADS score is noted in 73% on repeat MRI. Persistence of PI-RADS 4/5 predicts a higher risk of missed cancer, warranting prompt re-biopsy. While histologic findings such as inflammation may underlie some PI-RADS 4/5 abnormalities, initial histology is a poor predictor of cancer likelihood on repeat biopsy.

PURPOSE/OBJECTIVE:To demonstrate the generalizability of PRECISION findings and apply the PRECISION biopsy strategy to a contemporary cohort to characterize cancers missed by employing this strategy. MATERIALS AND METHODS/METHODS:629 men biopsied between 2/2015-9/2018 met PRECISION inclusion criteria. Men with PI-RADS 1-2 MRI were only biopsied if high clinical suspicion for cancer. Missed cancers were defined as prostate cancer (PCa) identified uniquely on systematic biopsy (SB) in men with PI-RADS 3-5 MRI, or on either SB or MRI-targeted prostate biopsy (MRI-TB) in men with PI-RADS 1-2 MRI. Outcomes included 1) clinically-significant PCa (csPCa), ≥Gleason grade group (GG) 2, detection rate (CDR), 2) missed csPCa rate upon application of PRECISION biopsy strategy, 3) GG distribution, core size, spatial orientation, and oncologic risk among missed cancers. RESULTS:Application of the PRECISION biopsy strategy to the study cohort resulted in avoidance of biopsy in 28%, similar MRI-TB CDR to PRECISION, reduction of GG1 CDR by 60%, and reduction of csPCa CDR by 19%. Missed csPCa were often <6 mm (54.5%), GG2 (67.3%), and low-risk by clinical nomogram (74.6%). GG1 cancers identified uniquely on SB were often contralateral to MRI target (46.4%), while missed csPCa was predominantly ipsilateral (81%). Limitations include biopsy of only men with high-risk clinical features among PIRADS 1-2 MRI, potentially overestimating the csPCa CDR. CONCLUSIONS:The study cohort demonstrated generalizability of PRECISION findings. Applying the PRECISION biopsy strategy greatly reduces GG1 CDR, while missing a small number of csPCa, typically small volume, low-risk, and GG2. Missed csPCa are predominantly ipsilateral to MRI target, possibly representing targeting error.

Background: Recent clinical guidelines for management of prostate adenocarcinoma are aimed at expanding active surveillance (AS) to include men with intermediate-risk (Gleason score 3+4=7) disease on needle biopsy (NB). However, studies reported a large portion of men with Gleason 3+4=7 prostate cancer on biopsy, that harbored adverse surgical pathologic findings. It remains unclear which subset of intermediate-risk patients with Gleason score 7 cancers can be safely treated with AS. In this study we investigate whether the percentage of Gleason pattern 4 in NB with Gleason score 7 cancers is an indicator for stratifying risk.
Design(s): We retrospectively reviewed our electronic record database for patients that underwent core NB over a 6-year period. We included NB with Gleason score 3+3=6 (G336), 3+4=7 with <5% Gleason pattern 4 (G4%<5) and 3+4=7 with 6-49% maximum Gleason pattern 4 (G4%6-49); all cases had corresponding radical prostatectomy (RP) within 6 months of the biopsy. We defined adverse pathology (AP) as any RP with Gleason score equal to or greater than 4+3=7 and/or stage T3 or higher. We compare AP outcomes in final follow-up RP of three NB groups: G336, G4%<5 and G4%6-49.
Result(s): A total of 289 NB with corresponding radical prostatectomies were identified. The breakdown of Gleason groups is shown in Table 1. GS336 has an AP rate of 26.6%, while G4<5% an AP rate of 20%. In comparison, the group of patients with G4%6-49 exhibited a 42% rate of AP (Table 1). A Chi-square test performed comparing AP of G4%<5 and G%6-49 is statistically significant p= .0237 (Figure 1). Conversely, there is no statistical difference between the rate of AP in G4<5% and G336, p= 0.46. G336 and G4%<5 were aggregated into a new group G%0-5 with an AP rate of 25.2% compared to G%6-10 AP rate 39.6%, p= 0.0576 (Figure 2). G4%6-10 and G4%11-49 had comparable rates of AP, 39.6% and 43.1%, respectively (p=0.681). (Table presented)
Conclusion(s): Currently there is a paradigm shift amongst pathologist and the significance of minimal percentage pattern 4 on prostate biopsies. Our current data supports the recent literature publications that <5% maximal Gleason pattern 4 on a single core has a similar rate of adverse pathological outcomes as Gleason score 3+3=6 and can be considered for AS. Although we did not detect a statistical difference between the rate of AP between G4%0-5 and G4%6-10, the data is beginning to approach statistical significance and warrants further risk stratification

Background: Clear cell papillary renal cell carcinoma (ccpRCC) is a relatively new entity and it has been described as an indolent renal neoplasm. ccpRCC shares features of clear cell RCC (ccRCC) and papillary RCC (pRCC) morphologically and immunohistochemically, even though it carries a very different prognostic potential. Epigenetic alterations play a significant role in the development and progression of human tumors. A large scale sequencing efforts demonstrated that hypermethylation in RCC tumors is associated with poor prognosis and may dictate treatment options. However, ccpRCC has not been included and further molecular elucidation is to be done. In this study, we attempt to investigate the methylation patterns in ccpRCC and test if differential patterns can be correlated with histologic subtypes and known biological behaviors.
Design(s): Nephrectomy specimens from our institution were reviewed and 8 cases from 2017-2019 were selected and confirmed as ccpRCC by three pathologists. Tumors were microdissected and DNA from FFPE was extracted and profiled using the Illumina MethylationEPIC array. Methylation data were analyzed with the R Bioconductor package minfi, including quality control, data normalization and differentially methylated CpG site analysis. Subsequent filtering was performed using a p-value cutoff = 0.01 and a minimum mean difference of the Beta-value of 0.1. Clustering was performed using tSNE analysis. Copy numbers were analyzed using conumee package. The methylation data were compared to ccRCC and pRCC from publicly available TCGA dataset.
Result(s): All 8 cases passed QC metrics on bisulfite conversion, hybridization and signal intensity confirming that the DNA quality was optimal for methylation study. ccpRCC clustered very tightly together illustrating that they represented a homogeneous group of tumors. When this cluster was compared to the TCGA dataset, ccpRCC was found to be located in between ccRCC and pRCC which might explain the characteristic features of this tumor subtype (figure 1). (Figure presented)
Conclusion(s): 1. DNA methylation is a useful molecular hallmark of many cancers including renal cancers and is increasingly utilized in diagnosis, prognostication, and clinical trials (epigenetic therapy). 2. Morphologically and immunohistochemically confirmed ccpRCC forms a tight cluster validating the use of methylation assay for future studies. 3. Promotor and pathway specific methylation patterns will be further studied which can distinguish the indolent clinical behavior

Background: Low risk prostate cancers are amenable to active surveillance which can reduce harmful overtreatment of indolent disease. However there is great variability of criteria in urological practice for determination of active surveillance candidacy. The quantity of Gleason pattern 4 is an important prognostic parameter and may influence treatment decisions. A genomic classifier, the Oncotype DX Genomic Prostate Score has been used to predict both clinical risk and tumor aggressiveness in patients diagnosed on biopsy with low risk prostate cancer (Grade group (GG) 1 and 2). This study investigated whether Genomic Prostate Score (GPS) can predict unfavorable disease and correlates with percentage of Gleason pattern 4 in low grade prostate cancer.
Design(s): We searched our surgical pathology database for prostate biopsies with Oncotype DX Genomic Prostate Score reports (2016- 2019). Oncotype Dx was performed on the single core with worst disease (core with longest tumor and/or maximum percentage of pattern 4). Biopsy results including Gleason Score and length of the tumor and percentage of pattern 4 from the core submitted for Oncotype test were recorded. Follow-up repeat biopsy or prostatectomy, if performed, were also retrieved for review of Gleason Score. Oncotype GPS score and related clinical information were analyzed in the study.
Result(s): 306 prostate biopsy cases with Oncotype DX test report were included in the study. Among these cases, 124 cases were originally diagnosed as GG1 (Gleason Score 3 + 3) and 182 cases were GG2 (3 + 4). The average GPS in GG 2 is significantly higher than GG1 (28.52 +/- 11.80 vs 17.88 +/- 9.35, p < 0.0001). Forty cases in GG1 had follow up repeat biopsy or prostatectomy. Twenty cases were upgraded to GG2. Cases with higher GPS score are more likely to upgrade to GG2 (23.10 +/- 10.13 vs 16.55 +/- 8.22, p < 0.05) in follow up repeat biopsy or prostatectomy. In GG1 group, GPS score correlated with the maximum tumor length and tumor percentage (p < 0.01). In GG2, patients with Gleason pattern 4 greater than 30% received higher GPS score than patients with pattern 4 less than 30% (p < 0.05). GPS significantly correlated with percentage of Gleason pattern 4 but not length of pattern 4, length of tumor, PSA level or PSA density.
Conclusion(s): In GG1, Oncotype Dx GPS can predict the likelihood of unfavorable disease at follow up repeat biopsy or prostatectomy. In GG2, GPS score correlated with percentage of pattern 4, supporting its role as an auxiliary tool for clinical risk classification

BACKGROUND:Differentiating parathyroid from thyroid lesions can be difficult on fine-needle aspiration (FNA) due to overlapping cytomorphologic features. While the traditional parathyroid hormone (PTH) assays can help in the distinction, these tests may be cumbersome, particularly when the lesion is unexpected clinically and a needle wash is not collected at the time of FNA. Therefore, we chose to investigate the application of immunohistochemical staining (IHC) with GATA 3 and thyroid transcription factor-1 (TTF-1) on air-dried cytology smears to distinguish parathyroid and thyroid lesions. METHODS:Air-dried touch preparation (TP) slides were prepared from consecutively selected parathyroid and thyroid specimens. Thirteen FNA cases with the clinical concern for parathyroid lesions were also included in the study. IHC was performed on unstained and ultrafast Papanicolaou (UFP) stained air-dried slides. RESULTS:On TP slides, GATA 3 expression was observed in all cases of parathyroid origin but no immunoreactivity was present in thyroid lesions. TTF-1 expression was observed in all cases of thyroid origin but not in parathyroid lesions. GATA 3 and TTF-1 expression of 13 FNA cases were consistent with the clinical impression or concurrent PTH tests. CONCLUSIONS:IHC with GATA 3 and TTF-1 on air-dried cytology smears is a simple and effective way to differentiate parathyroid vs thyroid lesions on FNA. Air-dried unstained and UFP-stained slides perform equally well with IHC, but UFP-stained slides provide the added benefit of morphologic evaluation and assessment of smear cellularity prior to IHC.