Histopathological factors versus margin size in single colorectal liver metastases: Does a 1-cm margin size matter?

Background and objective:

The ideal margin width for surgical resection of colorectal liver metastases has been extensively studied, but not sufficiently in accordance with other pathological factors. The aim of this study was to assess for the first time the prognostic impact of margin widths according to different prognostic pathological factors in colorectal liver metastasis.

Methods:

We evaluated 101 patients with a single resected metastasis. Slides stained by HE were assessed for the presence of poorly differentiated clusters, peritumoral inflammatory infiltrate, tumor pseudocapsule, and tumor borders pattern. Overall survival, disease-free survival, and hepatic recurrence were evaluated. The pathologic factors prognostic impact was evaluated according to a (< or ⩾) 10-mm margin size.

Results:

Factors independently associated with a shorter overall survival were absence of tumor pseudocapsule ( p < 0.001) and infiltrative tumor border pattern ( p = 0.019). The absence of tumor pseudocapsule was the only factor independently associated with shorter disease-free survival ( p < 0.001). Hepatic recurrence was associated with infiltrative tumor border and absence of pseudocapsule. Margin width ⩾10 mm did not impact overall survival independently of the studied histological prognostic factors.

Conclusions:

In colorectal liver metastasis resection, the absence of tumor pseudocapsule was significantly associated with shorter overall survival and disease-free survival and hepatic recurrence. However, margins larger than 10 mm did not offer survival benefit when other pathologic negative prognostic factors were concomitantly analyzed, reinforcing the idea that biology, rather than margin size, is crucial for prognosis.

Gastric cancer molecular classification and adjuvant therapy: Is there a different benefit according to the subtype?

BACKGROUND

Gastric cancer (GC) has been defined in distinct molecular subtypes with different therapeutic implications. However, its clinical significance and prognosis regarding standard chemotherapy (CMT) remains unclear. This study aimed to analyze the impact of perioperative or adjuvant treatment among subtypes of GC.

METHODS

We retrospectively evaluated all stage II/III patients with GC who underwent a curative gastrectomy. Based on immunohistochemistry and in situ hybridization techniques, GC was classified into five subtypes: Epstein-Barr virus (EBV) positive, microsatellite instability (MSI), e-cadherin aberrant, p53-aberrant, and p53-normal.

RESULTS

Among the 178 CG included, 111 patients received CMT and 67 were treated with surgery alone. Survival analysis showed that p53-aberrant GC treated with CMT had better disease-free survival (DFS) compared with surgery alone (P = .001).There was no significant difference in DFS between patients who received CMT and those with surgery alone for EBV, MSI, E-cadherin, and p53-normal GC. An improvement in overall survival was observed only for E-cadherin (P = .001) and p53-aberrant (P < .001) patients who received CMT.

CONCLUSIONS

CMT showed different impact on the survival of CG according to the molecular subtype. No survival benefit was observed for EBV and MSI groups who received CMT. GC with p53-aberrant had a significant benefit in survival with standard therapy.

Real-world evidence on first-line treatment for metastatic renal cell carcinoma with non-clear cell and sarcomatoid histologies: are sunitinib and pazopanib interchangeable?

Introduction

Non-clear cell renal cell carcinoma (nccRCC) and sarcomatoid renal cell carcinoma (sRCC) are underrepresented in clinical trials. Treatment approaches are frequently extrapolated from data of clear cell renal cell carcinoma, in which pazopanib is non-inferior to sunitinib. We aim to compare the effectiveness of first-line sunitinib and pazopanib for nccRCC and sRCC.

Methods

We evaluated a retrospective cohort of patients with metastatic nccRCC and sRCC treated with first-line sunitinib or pazopanib at an academic cancer centre. Overall survival (OS), progression-free survival (PFS) and response rate were measured. Kaplan–Meier and log-rank analyses were used for time-to-event data. Cox regression was used for prognostic factors.

Results

Fifty-three patients were included; 16 (30.1%) treated with sunitinib and 37 (69.9%) with pazopanib. Forty-six (86.8%) patients had nccRCC and 7 (13.2%) had sRCC. The majority had intermediate or poor International Metastatic Renal-Cell Carcinoma Database Consortium risk (93%).

Median PFS was 6.6 months with sunitinib and 4.9 months with pazopanib (HR 1.75; P = 0.078). Treatment with pazopanib was associated with inferior OS in comparison with sunitinib (median OS: 30.4 months versus 8.7 months; HR 2.71, 95% CI 1.31–5.58, P = 0.007). These results were confirmed in subgroup analysis of patients with papillary, chromophobe and MiT family translocation histologies (median OS: 38.7 months versus 14.7 months; HR 3.16, 95% CI 1.20–8.29, P = 0.019). Unclassified and sarcomatoid histologies had inferior OS (median: 6.9 and 1.1 months, respectively) regardless of the treatment used.

Conclusion

In this patient cohort, pazopanib was associated with inferior OS in comparison with sunitinib for metastatic nccRCC. Larger trials are ideally warranted to confirm these results.

Insulin-like growth factor-1 receptor expression in upper tract urothelial carcinoma

Insulin-like growth factor-1 receptor (IGF1R) is a transmembrane tyrosine kinase receptor that plays a crucial role in cell proliferation, growth, differentiation, and apoptosis. IGF1R overexpression has been observed in several cancers, including invasive bladder carcinomas, as a potential prognostic factor. Given known biologic differences between upper and lower urinary tract urothelial carcinoma, we assessed the expression status and prognostic significance of IGF1R in upper tract urothelial carcinoma (UTUC). Two tissue microarrays (TMAs) were built from 99 Japanese patients with non-metastatic UTUC submitted to radical nephroureterectomy between 1997 and 2011. TMAs were constructed with triplicate tumor and paired benign urothelium. Membranous IGF1R staining was evaluated using immunohistochemistry. Two scoring methods were applied (Her2-score and H-score). The highest score was assigned to each tumor. IGF1R positivity was defined as Her2-score ≥ 1+. Association with clinicopathologic parameters and outcome was assessed using hazard ratios (HR) with 95% confidence intervals (CI) and adjusted P values. We found positive IGF1R expression in 70% of UTUC. Outcomes were as follows: tumor recurrence, 33%; tumor progression, 59%; overall mortality, 33%; and cancer-specific mortality, 30%. IGF1R was not associated with any clinicopathologic features. In addition, IGF1R expression was not associated with tumor recurrence (HR = 0.54, CI = 0.25-1.1, P = 0.11), tumor progression (HR = 1.6, CI = 0.8-3.1, P = 0.19), overall mortality (HR = 1.5, CI = 0.68-3.4, P = 0.31), or cancer-specific mortality (HR = 1.6, CI = 0.68-3.8, P = 0.27). Positive IGF1R expression was found in more than two thirds of UTUC. This finding provides a rationale to investigate IGF1R as a potential therapeutic target in UTUC. In contrast to bladder cancer, IGF1R expression in UTUC did not correlate with outcome, further pointing to biologic differences between UTUC and bladder cancer.

Clinicopathological and prognostic features of Epstein-Barr virus infection, microsatellite instability, and PD-L1 expression in gastric cancer

BACKGROUND AND OBJECTIVES

Gastric cancer (GC) has recently been categorized in molecular subtypes, which include Epstein-Barr (EBV)-positive and microsatellite instability (MSI) tumors. This distinction may provide prognostic information and identifies therapeutic targets. The aim of this study was to evaluate EBV, MSI, and PD-L1 immunoexpression in GC and its relationship with clinicopathological characteristics and patient's prognosis.

METHODS

We evaluated 287 GC patients who underwent D2-gastrectomy through immunohistochemistry for DNA mismatch repair proteins and PD-L1, and in situ hybridization for EBV detection utilizing tissue microarray.

RESULTS

EBV-positive and MSI were identified in 10.5% and 27% of the GCs, respectively. EBV positivity was associated to male gender (P = 0.032), proximal location (P < 0.001), undetermined Lauren type (P < 0.001), poorly differentiated histology (P = 0.043) and severe inflammatory infiltrate (P < 0.001). MSI-tumors were associated to older age (P = 0.002), subtotal gastrectomy (P = 0.004), pN0 (P = 0.024) and earlier TNM stage (P = 0.020). PD-L1-positive was seen in 8.8% of cases, with predominant expression in EBV-positive GC (P < 0.001). MSI was associated to better survival outcomes.

CONCLUSION

EBV-positive GCs had increased PD-L1 expression, while MSI GC had better survival outcome. EBV and MSI subgroups are distinct GC entities, their recognition is feasible by conventional techniques, and it may help individualize follow-up and guide adjuvant therapy.

Pathological factors and prognosis of resected liver metastases of colorectal carcinoma: implications and proposal for a pathological reporting protocol

Colorectal cancer is a leading cause of death worldwide. The liver is the most common site of distant metastases, and surgery is the only potentially curative treatment, although the recurrence rate following surgery is high. In order to define prognosis after surgery, many histopathological features have been identified in the primary tumour. In turn, pathologists routinely report specific findings to guide oncologists on the decision to recommend adjuvant therapy. In general, the pathological report of resected colorectal liver metastases is limited to confirmation of the malignancy and details regarding the margin status. Most pathological reports of a liver resection for colorectal liver metastasis lack information on other important features that have been reported to be independent prognostic factors. We herein review the evidence to support a more detailed pathological report of the resected liver specimen, with attention to: the number and size of liver metastases; margin size; the presence of lymphatic, vascular, perineural and biliary invasion; mucinous pattern; tumour growth pattern; the presence of a tumour pseudocapsule; and the pathological response to neoadjuvant chemotherapy. In addition, we propose a new protocol for the evaluation of colorectal liver metastasis resection specimens.

Strong association of insulin-like growth factor 1 receptor expression with histologic grade, subtype, and HPV status in penile squamous cell carcinomas: a tissue microarray study of 112 cases

Insulin-like growth factor-1 receptor (IGF1R) plays a key role in cell growth and transformation. It is overexpressed in several solid tumors. This study evaluates IGF1R immunoexpression in penile squamous cell carcinoma (SCC). Four tissue microarrays were built from formalin-fixed, paraffin-embedded blocks of 112 penile SCC from Paraguay. Membranous IGF1R expression was evaluated by immunohistochemistry using two different approaches. An H-score was calculated in each spot (stain intensity by extent), and a median score per tumor was obtained. The second approach consisted of a score similar to the scoring system that was used for evaluating HER2 immunoexpression. For each case, the highest category obtained at any spot was used for statistical analyses. IGF1R expression was compared by histologic subtype, grade, and human papillomavirus (HPV) status. Median H-score was 22.5. The distribution of IGF1R expression by HER2 approach was as follows: 0 in 33.0% cases, 1+ in 46.4%, 2+ in 14.3%, and 3+ in 6.2%. IGF1R H-scores were associated with basaloid and warty/basaloid subtypes (p = 0.0026) and higher grade (p = 0.00052). Although weaker when using the HER2 approach, the association of IGF1R expression with subtype (p = 0.015) and grade (p = 0.015) remained significant. Furthermore, there was an association between IGF1R expression by HER2 approach and HPV status (p = 0.012). IGF1R was expressed in about two thirds of penile SCC cases, showing a strong positive association with histologic grade, subtype, and HPV status. Considering that grade is a predictor of outcome IGF1R expression may have prognostic relevance and could point to a potential role for IGF1R inhibitors in treating penile SCC.

Comprehensive Determination of Prostate Tumor ETS Gene Status in Clinical Samples Using the CLIA Decipher Assay

ETS family gene fusions are common in prostate cancer and molecularly define a tumor subset. ERG is the most commonly rearranged, leading to its overexpression, followed by ETV1, ETV4, and ETV5, and these alterations are generally mutually exclusive. We validated the Decipher prostate cancer assay to detect ETS alterations in a Clinical Laboratory Improvement Amendments-accredited laboratory. Benchmarking against ERG immunohistochemistry and ETV1/4/5 RNA in situ hybridization, we examined the accuracy, precision, and reproducibility of gene expression ETS models using formalin-fixed, paraffin-embedded samples. The m-ERG model achieved an area under curve of 95%, with 93% sensitivity and 98% specificity to predict ERG immunohistochemistry status. The m-ETV1, -ETV4, and -ETV5 models achieved areas under curve of 98%, 88%, and 99%, respectively. The models had 100% robustness for ETS status, and scores were highly correlated across sample replicates. Models predicted 41.5% of a prospective radical prostatectomy cohort (n = 4036) to be ERG⁺, 6.3% ETV1⁺, 1% ETV4⁺, and 0.4% ETV5⁺. Of prostate tumor biopsy samples (n = 509), 41.2% were ERG⁺, 8.6% ETV1⁺, 0.4% ETV4⁺, and none ETV5⁺. Higher Decipher risk status tumors were more likely to be ETS⁺ (ERG or ETV1/4/5) in the radical prostatectomy and the biopsy cohorts (P < 0.05). These results support the utility of microarray-based ETS status prediction models for molecular classification of prostate tumors.

Prognostic role and implications of mutation status of tumor suppressor gene ARID1A in cancer: a systematic review and meta-analysis

Loss of the tumor suppressor gene AT-rich interactive domain-containing protein 1A (ARID1A) has been demonstrated in several cancers, but its prognostic role is unknown. We aimed to investigate the risk associated with loss of ARID1A (ARID1A−) for all-cause mortality, cancer-specific mortality and recurrence of disease in subjects with cancer. PubMed and SCOPUS search from database inception until 01/31/2015 without language restriction was conducted, contacting authors for unpublished data. Eligible were prospective studies reporting data on prognostic parameters in subjects with cancer, comparing participants with presence of ARID1A (ARID1A+) vs. ARID1A−, assessed either via immunohistochemistry (loss of expression) or with genetic testing (presence of mutation). Data were summarized using risk ratios (RR) for number of deaths/recurrences and hazard ratios (HR) for time-dependent risk related to ARID1A− adjusted for potential confounders. Of 136 hits, 25 studies with 5,651 participants (28 cohorts; ARID1A−: n = 1,701; ARID1A+: n = 3,950), with a mean follow-up period of 4.7 ± 1.8 years, were meta-analyzed. Compared to ARID1A+, ARID1A− significantly increased cancer-specific mortality (studies = 3; RR = 1.55, 95% confidence interval (CI) = 1.19–2.00, I² = 31%). Using HRs adjusted for potential confounders, ARID1A− was associated with a greater risk of cancer-specific mortality (studies = 2; HR = 2.55, 95%CI = 1.19–5.45, I² = 19%) and cancer recurrence (studies = 10; HR = 1.93, 95%CI = 1.22–3.05, I² = 76%). On the basis of these results, we have demonstrated that loss of ARID1A shortened time to cancer-specific mortality, and to recurrence of cancer when adjusting for potential confounders. For its role, this gene should be considered as an important potential target for personalized medicine in cancer treatment.

SPINK1 Defines a Molecular Subtype of Prostate Cancer in Men with More Rapid Progression in an at Risk, Natural History Radical Prostatectomy Cohort

PURPOSE

Prostate cancer is clinically and molecularly heterogeneous. We determined the prognosis of men with ERG-ETS fusions and SPINK1 over expression.

MATERIALS AND METHODS

Men were identified with intermediate or high risk localized prostate cancer treated with radical prostatectomy and no therapy before metastasis. A case-cohort design sampled a cohort (262) enriched with metastasis from the entire cohort and a cohort (213) enriched with metastasis from patients with biochemical recurrence. We analyzed transcriptomic profiles and subtyped tumors as m-ERG⁺, m-ETS⁺, m-SPINK1⁺ or Triple Negative (m-ERG^─/m-ETS^─/m-SPINK1^─), and multivariable logistic regression analyses, Kaplan-Meier and multivariable Cox models were used to evaluate subtypes as predictors of clinical outcomes.

RESULTS

Overall 36%, 13%, 11% and 40% of prostate cancer was classified as m-ERG⁺, m-ETS⁺, m-SPINK1⁺ and Triple Negative, respectively. Univariable analysis demonstrated that m-SPINK1⁺ tumors were more common in African-American men (OR 5, 95% CI 1.6-16) but less commonly associated with positive surgical margins (OR 0.16, 95% CI 0.03-0.69) compared to the m-ERG⁺ group. Compared to the Triple Negative group, m-SPINK1⁺ showed similar associations with race and surgical margins in univariable and multivariable analyses across the entire cohort. Survival analyses did not show significant differences among m-ERG⁺, m-ETS⁺ and Triple Negative cases. m-SPINK1⁺ independently predicted prostate cancer specific mortality after metastasis (HR 2.48, 95% CI 0.96-6.4) and biochemical recurrence (HR 3, 95% CI 1.1-8).

CONCLUSIONS

SPINK1 over expression is associated with prostate cancer specific mortality in at risk men with biochemical and clinical recurrence after prostatectomy. ERG-ETS alterations are not prognostic for outcome.

Prevalence of human papillomavirus types and variants and p16(INK4a) expression in head and neck squamous cells carcinomas in São Paulo, Brazil

Background

Human papillomavirus (HPV) prevalence in head and neck squamous cell carcinomas (HNSCC) diverges geographically. The reliability of using p16^INK4a expression as a marker of viral infection is controversial in HNSCC. We evaluated HPV types and HPV-16 variants prevalence, and p16^INK4a expression in HNSCC specimens provided by two different Institutions in São Paulo.

Methods

HPV DNA from formalin-fixed specimens was accessed by Inno-LiPA, HPV-16 variants by PCR-sequencing, and p16^INK4a protein levels by immunohistochemistry.

Results

Overall, HPV DNA was detected among 19.4 % of the specimens (36/186). Viral prevalence was higher in the oral cavity (25.0 %, 23/92) then in other anatomical sites (oropharynx 14,3 %, larynx 13.7 %) when samples from both Institutions were analyzed together. HPV prevalence was also higher in the oral cavity when samples from both Institutions were analyzed separately. HPV-16 was the most prevalent type identified in 69.5 % of the HPV positive smaples and specimens were assigned into Asian-American (57.2 %) or European (42.8 %) phylogenetic branches. High expression of p16^INK4a was more common among HPV positive tumors.

Conclusion

Our results support a role for HPV-16 in a subset of HNSCC.

Overexpression of Insulin-like Growth Factor-1 Receptor Is Associated With Penile Cancer Progression

OBJECTIVE

To evaluate insulin-like growth factor-1 receptor (IGF1R) expression in penile cancer and its association with oncologic outcomes.

METHODS

Tissue microarrays were constructed from 53 patients treated at our institution. Expression of IGF1R was evaluated using a Her2-like scoring system. Overexpression was defined as 1+ or greater membranous staining. Association of IGF1R expression with pathologic features was assessed with comparative statistics, and association with local recurrence, progression to nodal or distance metastases, or death was assessed with Kaplan-Meier survival analysis and Cox proportional hazard regression models.

RESULTS

Overall, IGF1R overexpression was seen in 33 (62%) cases. With a median follow-up of 27.8 months, IGF1R overexpression was associated with inferior progression-free survival (PFS) (P  =  .003). In a multivariable model controlling for grade, T stage, perineural invasion, and lymphovascular invasion, IGF1R expression was independently associated with disease progression (hazard ratio 2.3, 95% confidence interval 1.1-5.1, P  =  .03. Comparing patients without IGF1R overexpression to those with overexpression, 5-year PFS was 94.1% vs 45.8%.

CONCLUSION

IGF1R overexpression was associated with inferior PFS in penile cancer. Drugs that target IGF1R and downstream messengers may have a therapeutic benefit in patients that exhibit IGF1R overexpression.

Germline Variants in Asporin Vary by Race, Modulate the Tumor Microenvironment, and Are Differentially Associated with Metastatic Prostate Cancer

PURPOSE

Prostate cancers incite tremendous morbidity upon metastatic growth. We previously identified Asporin (ASPN) as a potential mediator of metastatic progression found within the tumor microenvironment. ASPN contains an aspartic acid (D)-repeat domain and germline polymorphisms in D-repeat-length have been associated with degenerative diseases. Associations of germline ASPN D polymorphisms with risk of prostate cancer progression to metastatic disease have not been assessed.

EXPERIMENTAL DESIGN

Germline ASPN D-repeat-length was retrospectively analyzed in 1,600 men who underwent radical prostatectomy for clinically localized prostate cancer and in 548 noncancer controls. Multivariable Cox proportional hazards models were used to test the associations of ASPN variations with risk of subsequent oncologic outcomes, including metastasis. Orthotopic xenografts were used to establish allele- and stroma-specific roles for ASPN D variants in metastatic prostate cancer.

RESULTS

Variation at the ASPN D locus was differentially associated with poorer oncologic outcomes. ASPN D14 [HR, 1.72; 95% confidence interval (CI), 1.05-2.81, P = 0.032] and heterozygosity for ASPN D13/14 (HR, 1.86; 95% CI, 1.03-3.35, P = 0.040) were significantly associated with metastatic recurrence, while homozygosity for the ASPN D13 variant was significantly associated with a reduced risk of metastatic recurrence (HR, 0.44; 95% CI, 0.21-0.94, P = 0.035) in multivariable analyses. Orthotopic xenografts established biologic roles for ASPN D14 and ASPN D13 variants in metastatic prostate cancer progression that were consistent with patient-based data.

CONCLUSIONS

We observed associations between ASPN D variants and oncologic outcomes, including metastasis. Our data suggest that ASPN expressed in the tumor microenvironment is a heritable modulator of metastatic progression.

Androgen-Regulated SPARCL1 in the Tumor Microenvironment Inhibits Metastatic Progression

Prostate cancer is a leading cause of cancer death in men due to the subset of cancers that progress to metastasis. Prostate cancers are thought to be hardwired to androgen receptor (AR) signaling, but AR-regulated changes in the prostate that facilitate metastasis remain poorly understood. We previously noted a marked reduction in secreted protein, acidic and rich in cysteine-like 1 (SPARCL1) expression during invasive phases of androgen-induced prostate growth, suggesting that this may be a novel invasive program governed by AR. Herein, we show that SPARCL1 loss occurs concurrently with AR amplification or overexpression in patient-based data. Mechanistically, we demonstrate that SPARCL1 expression is directly suppressed by androgen-induced AR activation and binding at the SPARCL1 locus via an epigenetic mechanism, and these events can be pharmacologically attenuated with either AR antagonists or HDAC inhibitors. We establish using the Hi-Myc model of prostate cancer that in Hi-Myc/Sparcl1(-/-) mice, SPARCL1 functions to suppress cancer formation. Moreover, metastatic progression of Myc-CaP orthotopic allografts is restricted by SPARCL1 in the tumor microenvironment. Specifically, we show that SPARCL1 both tethers to collagen in the extracellular matrix (ECM) and binds to the cell's cytoskeleton. SPARCL1 directly inhibits the assembly of focal adhesions, thereby constraining the transmission of cell traction forces. Our findings establish a new insight into AR-regulated prostate epithelial movement and provide a novel framework whereby SPARCL1 in the ECM microenvironment restricts tumor progression by regulating the initiation of the network of physical forces that may be required for metastatic invasion of prostate cancer.

¹⁸F-DCFBC PET/CT for PSMA-Based Detection and Characterization of Primary Prostate Cancer

We previously demonstrated the ability to detect metastatic prostate cancer using N-[N-[(S)-1,3-dicarboxypropyl]carbamoyl]-4-(18)F-fluorobenzyl-L-cysteine ((18)F-DCFBC), a low-molecular-weight radiotracer that targets the prostate-specific membrane antigen (PSMA). PSMA has been shown to be associated with higher Gleason grade and more aggressive disease. An imaging biomarker able to detect clinically significant high-grade primary prostate cancer reliably would address an unmet clinical need by allowing for risk-adapted patient management.

METHODS

We enrolled 13 patients with primary prostate cancer who were imaged with (18)F-DCFBC PET before scheduled prostatectomy, with 12 of these patients also undergoing pelvic prostate MR imaging. Prostate (18)F-DCFBC PET was correlated with MR imaging and histologic and immunohistochemical analysis on a prostate-segment (12 regions) and dominant-lesion basis. There were no incidental extraprostatic findings on PET suggestive of metastatic disease.

RESULTS

MR imaging was more sensitive than (18)F-DCFBC PET for detection of primary prostate cancer on a per-segment (sensitivities of up to 0.17 and 0.39 for PET and MR imaging, respectively) and per-dominant-lesion analysis (sensitivities of 0.46 and 0.92 for PET and MR imaging, respectively). However, (18)F-DCFBC PET was more specific than MR imaging by per-segment analysis (specificities of 0.96 and 0.89 for PET and MR imaging for corresponding sensitivity, respectively) and specific for detection of high-grade lesions (Gleason 8 and 9) greater than 1.0 mL in size (4/4 of these patients positive by PET). (18)F-DCFBC uptake in tumors was positively correlated with Gleason score (ρ = 0.64; PSMA expression, ρ = 0.47; and prostate-specific antigen, ρ = 0.52). There was significantly lower (18)F-DCFBC uptake in benign prostatic hypertrophy than primary tumors (median maximum standardized uptake value, 2.2 vs. 3.5; P = 0.004).

CONCLUSION

Although the sensitivity of (18)F-DCFBC for primary prostate cancer was less than MR imaging, (18)F-DCFBC PET was able to detect the more clinically significant high-grade and larger-volume tumors (Gleason score 8 and 9) with higher specificity than MR imaging. In particular, there was relatively low (18)F-DCFBC PET uptake in benign prostatic hypertrophy lesions, compared with cancer in the prostate, which may allow for more specific detection of primary prostate cancer by (18)F-DCFBC PET. This study demonstrates the utility of PSMA-based PET, which may be used in conjunction with MR imaging to identify clinically significant prostate cancer.

Assessment of tumoral PD-L1 expression and intratumoral CD8+ T cells in urothelial carcinoma

OBJECTIVE

To evaluate programmed death ligand 1 (PD-L1) expression in urothelial carcinoma of the bladder in relationship with tumor-infiltrating CD8+ T cells.

MATERIALS AND METHODS

Tissue microarrays were prepared from 56 cystectomy specimens performed at our hospital (1994-2002). PD-L1 immunoexpression was assessed using the murine antihuman PD-L1 monoclonal antibody 5H1. Extent of membranous PD-L1 expression was assigned in each spot. Spots showing ≥5% expression were considered positive. Average PD-L1 expression per tumor was also calculated (5% positivity cutoff). "High CD8 density" was defined as the presence of ≥60 CD8+ intraepithelial lymphocytes per high power field in a given spot. A tumor was considered high density if ≥50% of its spots were of high density.

RESULTS

PD-L1 expression was positive in approximately 20% of tumors. None of the benign urothelium spots expressed PD-L1. High CD8 density was observed in approximately 20% of cases. CD8 density did not correlate with PD-L1 expression. Overall survival (OS) and disease-specific survival (DSS) rates were 14% and 28%, respectively (median follow-up, 31.5 months). PD-L1 expression was associated with age at cystectomy (P = .01). Remaining clinicopathologic parameters were not associated with PD-L1 expression or CD8 density. High CD8 density was associated with favorable OS (P = .02) and DSS (P = .02). The same was true when CD8 density was adjusted for demographic and clinicopathologic parameters. There was no correlation between PD-L1 expression and outcome.

CONCLUSION

High intratumoral CD8+ T cell density is associated with better OS and DSS in invasive urothelial carcinoma of the bladder. We found no correlation between PD-L1 expression and outcome.

Immunohistochemical expression of ARID1A in penile squamous cell carcinomas: a tissue microarray study of 112 cases

ARID1A, a member of the chromatin remodeling genes family, has been suggested as a novel tumor suppressor gene in gynecologic malignancies. However, its role in penile cancer has yet to be determined. This study assesses the immunohistochemical expression of ARID1A in penile squamous cell carcinoma (SCC) and its association with pathologic features, human papillomavirus (HPV) status, and previously reported mammalian target of rapamycin pathway markers in the same cohort. Four tissue microarrays were constructed from 112 cases of formalin-fixed, paraffin-embedded penile SCC from Paraguay. Each tumor was sampled 3 to 12 times. ARID1A expression was evaluated by immunohistochemistry using a polyclonal rabbit anti-ARID1A (BAF250A) antibody. An H score was calculated in each spot as the sum of expression intensity (0-3+) by extent (0%-100%). Median H score per case was used for statistical analysis. ARID1A expression was observed in all cases, ranging from 3% to 100% of tumor cells (median, 95%). In 96 cases (86%), ARID1A expression was observed in 90% or more tumor cells. HPV DNA was detected in 20 (38%) of 52 analyzed samples. There was a significant trend of association between ARID1A and histologic grade. ARID1A expression was not associated with histologic subtype (P = .61) or HPV status (P = .18). ARID1A expression decreased with decreasing levels of PTEN expression (P = .01). ARID1A was expressed in penile SCC, in most cases at high levels. A significant trend of association was found between histologic grade and ARID1A expression, with lower ARID1A expression, lower histologic grades, and decreased PTEN expression.

ARID1A immunohistochemistry improves outcome prediction in invasive urothelial carcinoma of urinary bladder

AT-rich interactive domain 1A (ARID1A) is tumor suppressor gene that interacts with BRG1 adenosine triphosphatase to form a SWI/SNF chromatin remodeling protein complex. Inactivation of ARID1A has been described in several neoplasms, including epithelial ovarian and endometrial carcinomas, and has been correlated with prognosis. In the current study, ARID1A expression in urothelial carcinoma (UC) of the bladder and its association with clinicopathological parameters and outcome are addressed. Five tissue microarrays were constructed from 136 cystectomy specimens performed for UC at our institution. Nuclear ARID1A staining was evaluated using immunohistochemistry. An H-score was calculated as the sum of the products of intensity (0-3) multiplied by extent of expression (0%-100%). Average H-score per case was used for statistical analysis. ARID1A expression was categorized in low and high using Youden index to define the cut point. ARID1A expression significantly increased from normal to noninvasive UC to invasive UC. For both tumor progression and cancer death, Youden index yielded an H-score of 288 as the optimal cut point for ARID1A expression. Low ARID1A expression showed a tendency for lower risk of tumor progression and cancer mortality. Adding ARID1A expression to pathologic features offers a better model for predicting outcome than pathologic features alone. Low ARID1A expression was more frequently seen in earlier stage disease. There was a tendency for low ARID1A expression to predict better outcome. More importantly, the findings indicate that adding ARID1A expression to pathologic features increases the goodness of fit of the predictive model.

High frequency of TERT promoter mutation in small cell carcinoma of bladder, but not in small cell carcinoma of other origins

TERT promoter mutations were recently discovered in melanoma by next generation sequencing. Subsequently, several malignancies including urothelial carcinoma were also found to be associated with the same TERT promoter mutations. Small cell carcinoma (SCC) of the urinary bladder is a rare subtype with an aggressive clinical course. Despite the frequent occurrence of TERT promoter mutations in urothelial carcinoma, the incidence of the mutations in SCC of the urinary bladder is unknown. In addition, as a potential molecular marker to distinguish SCC of the urinary bladder from SCC of the prostate, lung (SCLC) and other origins, this information may be clinically useful. We collected a total of 11 cases of SCC of the urinary bladder (10 cases are primary SCC of the urinary bladder; 1 case has primary SCC of the urinary bladder and liver metastasis). We also included 20 cases of SCLC, 2 cases of SCC of the prostate, 5 cases of Merkel cell carcinoma, and 6 cases of SCC from other sites (cervical, GE junction, breast, and soft tissue). In addition, 3 cases of non-neoplastic tissue from the matched SCC of bladder patient and 14 cases of benign urinary bladder were also included. All tumor sections have been examined to confirm the diagnosis and to make sure more than 20% are of tumor content. Genomic DNA was isolated from FFPE tissue and a fragment of the TERT promoter (145 bp) was amplified by PCR. The TERT promoter mutations are determined by bi-directional Sanger sequencing. All (11/11) SCC of the urinary bladder bear TERT promoter mutation C228T. Neither of SCC from all other origins nor matched non-neoplastic tissue contains the TERT promoter mutations. We demonstrated a high frequency TERT promoter mutation in SCC of the urinary bladder, but not in SCC of other origin, such as the prostate. The findings further illustrate molecular differences between SCC of the urinary bladder and SCC of other origins, despite their shared morphologic and immunophenotypic similarities. The TERT promoter mutation may be a biomarker differentiating SCC of the urinary bladder from SCC of other origins.

TERT promoter mutations occur early in urothelial neoplasia and are biomarkers of early disease and disease recurrence in urine

Activating mutations occur in the promoter of the telomerase reverse transcriptase (TERT) gene in 66% of muscle-invasive urothelial carcinomas. To explore their role in bladder cancer development and to assess their utility as urine markers for early detection, we sequenced the TERT promoter in 76 well-characterized papillary and flat noninvasive urothelial carcinomas, including 28 pTa low-grade transitional cell carcinomas (TCC), 31 pTa high-grade TCCs, and 17 pTis carcinoma in situ lesions. We also evaluated the sequence of the TERT promoter in a separate series of 14 early bladder neoplasms and matched follow-up urine samples to determine whether urine TERT status was an indicator of disease recurrence. A high rate of TERT promoter mutation was observed in both papillary and flat lesions, as well as in low- and high-grade noninvasive urothelial neoplasms (mean: 74%). In addition, among patients whose tumors harbored TERT promoter mutations, the same mutations were present in follow-up urines in seven of eight patients that recurred but in none of the six patients that did not recur (P < 0.001). TERT promoter mutations occur in both papillary and flat lesions, are the most frequent genetic alterations identified to date in noninvasive precursor lesions of the bladder, are detectable in urine, and seem to be strongly associated with bladder cancer recurrence. These provocative results suggest that TERT promoter mutations may offer a useful urinary biomarker for both early detection and monitoring of bladder neoplasia.

Activation of mammalian target of rapamycin signaling pathway markers in minute adenocarcinoma of the prostate

OBJECTIVE

To asses the mammalian target of rapamycin (mTOR) pathway in minute prostatic adenocarcinoma on the basis of the previously reported role of phosphatase and tensin homolog (PTEN) inactivation and mTOR pathway activation as a negative prognosticator in prostatic cancer.

METHODS

Tissue microarrays were constructed from 42 consecutive radical prostatectomy specimens with minute prostatic adenocarcinoma. Standard immunohistochemistry analysis for mTOR pathway members PTEN, phos-S6, phos-4E-BP1, phos-mTOR, phos-AKT, p27, and ERG was performed. For all markers, histologic expression score was calculated as the sum of intensity × extent of expression. In addition, for PTEN, presence of "markedly decreased" expression (any focal absence of expression) was also assessed. Expression status of all biomarkers was compared between tumor and paired benign tissue. Intercorrelation among markers was also performed.

RESULTS

PTEN expression was seen in all 36 evaluable minute prostatic adenocarcinoma. Cytoplasmic phos-S6 was present in 32 of 36 tumors (89%). phos-S6 expression levels were higher in tumors compared with paired benign tissue (P = .007). Cytoplasmic and nuclear phos-4E-BP1 was present in all 34 evaluable tumors. phos-4E-BP1 was significantly higher in cancer compared with normal tissue (P <.0001). Only a minority of tumors demonstrating higher phos-S6 expression and phos-4E-BP1 (2 of 32 and 2 of 34, respectively) had associated "markedly decreased" PTEN expression.

CONCLUSION

We found evidence of activation of mTOR pathway in minute prostatic adenocarcinoma that appears to be unrelated to "markedly decreased" PTEN expression. The latter finding suggests an alternative signaling mechanism controlling mTOR activation in minute prostate carcinoma.

Immunohistochemical expression of SALL4 in hepatocellular carcinoma, a potential pitfall in the differential diagnosis of yolk sac tumors

SALL4 is a transcription factor that serves as a marker of yolk sac tumor. Yolk sac tumor and hepatocellular carcinoma share histologic, serologic, and immunohistochemical features. Previous studies have shown lack of SALL4 expression in hepatocellular carcinoma, suggesting utility in this differential diagnosis. Sixty-nine samples of hepatocellular carcinoma were retrieved from surgical pathology archives and used to construct 9 tissue microarrays. A germ cell tumor tissue microarray containing 10 yolk sac tumors was used for comparison. Extent, intensity, and pattern of nuclear SALL4 expression were assessed in each spot. Mean percentage of expression was calculated for each tumor and used during analysis. Optimal discriminatory extent of expression cutoff was determined by receiver operating characteristic curve analysis. Other potential discriminatory markers including Hep Par1 were also evaluated. Forty-six percent (32/69) of hepatocellular carcinoma and all yolk sac tumors revealed at least focal expression of SALL4. A unique punctuate/clumped pattern of nuclear staining was present in 94% (30/32) of hepatocellular carcinoma, whereas all yolk sac tumors displayed a diffuse finely granular nuclear staining pattern. A 25% extent of SALL4 expression cutoff was found to be optimal for the distinction of yolk sac tumor from hepatocellular carcinoma yielding a sensitivity of 100%, specificity of 92.8%, and a positive predictive value of 66.6% for yolk sac tumor diagnosis. The addition of Hep Par1 increased the specificity (99%) and positive predictive value (90%). This is the first report of SALL4 expression in hepatocellular carcinoma. Our finding should be taken into consideration in the differential diagnosis of hepatocellular carcinoma and yolk sac tumor. The unique punctuate/clumped pattern seen in hepatocellular carcinoma cases could be of further discriminatory value.

Case of hereditary papillary renal cell carcinoma

Renal cell carcinoma is the most common type of renal malignancy and it originates from the renal tubular epithelium. Due to the diversity in the histopathological and molecular characteristics, it is typically subclassified into five different categories. Papillary renal cell carcinoma is one subclassification and it includes two variants: sporadic and hereditary. Although the hereditary form comprises a smaller number of cases of papillary renal cell carcinoma, an understanding of the molecular pathways and genetic changes continues to play a significant role in the development of new targeted therapies. Along with recommending appropriate lifestyle modification, further investigation into the molecular pathogenesis of hereditary papillary renal cell carcinoma will continue to be invaluable for the clinical management of renal cell carcinoma. In this article, we discuss a case of the hereditary papillary renal cell carcinoma along with an overview of the disease.