Leiomyosarcoma of the urinary bladder: A SEER database study and comparison to leiomyosarcomas of the uterus and extremities/trunk

No well-established staging system exists for bladder leiomyosarcoma (LMS), and the current staging system does not include tumor size, a thoroughly validated prognostic parameter for sarcomas. Uterine and extremity/trunk LMS are more common than those in the bladder and have well-established staging systems incorporating tumor size. We aim to improve the understanding of LMS of the urinary bladder by assessing cancer-specific survival (CSS) and comparing LMS at this unusual anatomic site to those arising at other sites using the Surveillance, Epidemiology, and End Results (SEER) database. The SEER database (1973-2013) was queried for bladder, uterus, and trunk/extremity LMS. Multivariable Cox proportional hazard regression was performed to identify predictors of CSS for each anatomic location and used to compare outcomes at different sites. We identified 165 bladder, 4987 uterus, and 2536 extremity/trunk LMS cases. Five-year CSS was 52% for uterus, 73% for bladder, and 82% for extremity/trunk LMS. For LMS at all sites, uterine location (HR = 2.14, P < 0.001) and increasing tumor size (HR = 1.05, P < 0.001) were significant predictors of worse CSS on multivariate analysis. For bladder LMS, increasing tumor size (HR = 1.18, P = 0.003) was an independent prognostic factor and the conventional staging cut-off threshold of 5 cm for sarcomas outside the head/neck showed statistical significance in stratifying patient risk of cancer-related death. Bladder LMS appears to have clinical behavior intermediate between those of the extremities/trunk and uterus. We suggest that the conventional sarcoma staging protocols based on tumor size be applied to LMS of the urinary bladder.

Diagnostic renal mass biopsy is associated with individual categories of PADUA and RENAL nephrometry scores: Analysis of diagnostic and concordance rates with surgical resection

BACKGROUND

Renal mass biopsy (RMB) is a safe and accurate method for diagnosis and clinical management of renal masses. However, the non-diagnostic rate is a limiting factor. We tested the hypothesis that imaging characteristics and anatomic complexity of the mass may impact RMB diagnostic outcome using the preoperative aspects and dimensions used for an anatomical (PADUA) classification and radius-exophytic/endophytic-nearness-anterior/posterior-location (RENAL) score.

MATERIAL AND METHODS

Single institution, retrospective study of 490 renal masses from 443 patients collected from 2001 to 2018. Outcome measurements include (1) diagnostic and concordance rates amongst RMB types and RMB with surgical resection specimens; (2) association between diagnostic RMB and anatomical complexity of renal masses. The analysis was conducted in unselected masses and small renal masses (SRMs).

RESULTS

RMB was performed by fine needle aspiration (FNA), core needle biopsy (CNB), or both (FNA+CNB). Non-diagnostic rate was significantly higher for FNA compared to CNB and FNA+CNB in both unselected and SRMs. Subset analysis in the FNA+CNB group showed similar diagnostic rates for FNA and CNB. In unselected masses, specificity for FNA, CNB, and FNA+CNB was 100%. Sensitivity was higher for CNB (90.1%, P = 0.002) and FNA+CNB (96.3%, P = 0.004) compared to FNA (66.7%). For unselected masses, endophytic growth predicted a non-diagnostic CNB. R.E.N.A.L location entirely between the polar lines (central) and entirely above the upper polar line predicted a diagnostic CNB. Sonography-guidance predicted a diagnostic FNA. For SRMs, non-diagnostic CNB was associated with endophytic growth, while diagnostic CNB was associated with renal sinus invasion and operator experience. More cystic masses were sampled by FNA, but diagnostic results were similar for FNA and CNB.

CONCLUSIONS

Endophytic growth consistently predicted a non-diagnostic CNB in unselected and SRMs, whereas sonography-guidance predicted a diagnostic FNA. Cystic masses could be adequately sampled by FNA.

Chronic femoral diaphyseal osteomyelitis with radiographs initially concerning for Paget disease of the bone

Chronic osteomyelitis can be difficult to diagnose given its similar radiographic appearance to other lesions. This case report describes a 48-year-old woman, who presented with left thigh pain and on radiography a large disorganized sclerotic lesion involving nearly the entire femoral diaphysis, concerning for Paget disease or malignancy. Biopsy suggested chronic osteomyelitis but did not identify a causative organism. Treatment with antibiotics led to resolution of pain and improvement of biochemical markers. This case exemplifies the role of radiographic imaging in the diagnosis of chronic osteomyelitis and the possible utility of antibiotics for culture-negative chronic osteomyelitis. We review imaging modalities for the diagnosis of chronic osteomyelitis and Paget disease.

PD-L1 Expression Patterns in Microsatellite Instability-High Intestinal Adenocarcinoma Subtypes

OBJECTIVES

To investigate patterns of programmed death protein-1 (PD-L1) expression in microsatellite instability (MSI)-high intestinal carcinomas and correlate them with pathologic and molecular features.

METHODS

One hundred and fifteen MSI-high and 41 microsatellite stable carcinomas were included. Tumor sections were immunohistochemically labeled for PD-L1. The results were correlated with histologic subtypes, MSI, and BRAF status.

RESULTS

As expected, MSI status was associated with PD-L1 expression. Among 115 MSI-high tumors, PD-L1 expression was observed on tumor cells in 28 tumors and on tumor-associated inflammatory cells in 77 tumors. Medullary carcinoma demonstrated more frequent PD-L1 expression on tumor cells than mucinous and typical adenocarcinoma. PD-L1 expression was more frequent in medullary and typical adenocarcinoma than in mucinous adenocarcinoma based on combined positive scores. Tumors with more nucleotide shifts by PCR-based MSI testing were more likely to express PD-L1.

CONCLUSIONS

Expression of PD-L1 is different among different histologic subtypes of MSI-high intestinal carcinomas.

Abstract 2876: p21-activated kinase 1 is a novel therapeutic target for metastatic osteosarcoma harboring p27 mislocalization

Lung metastasis is the leading cause of death in osteosarcoma (OS), the most common bone cancer in children and young adults. Due to a lack of biomarkers and therapeutic targets, significant progress has not been made in the treatment of metastatic OS over the past three decades. The survival of metastatic patients remains dismal. We have previously reported that the tumor suppressor protein p27 (KIP1, CDKN1B) is frequently mislocalized in the cytoplasm of OS, which promotes the motility and invasiveness of the tumor cells and the development of pulmonary metastases in mice. In this study, we showed that a higher proportion score of cytoplasmic p27 significantly correlated with metastases developed within 3- or 5-year of follow-up, and poor disease-specific and event-free survival in a large OS cohort (n=136). Using immunoprecipitation followed by mass spectrometry, we demonstrated that cytoplasmic p27 interacted with p21-activated kinase 1 (PAK1), where the two proteins co-localized in the cytoplasm of OS cells. PAK1 is a serine/threonine kinase that has been implicated in various cancers; however, its role in OS is still elusive. We showed that the phosphorylations at serine-144 and threonine-423 residues of PAK1 were higher in the p27-mislocalized cells relative to the control cells. The PAK1 phosphorylations increased actin stress fiber formation in the tumor cells. Gene silencing or therapeutic inhibition of PAK1 reduced the motility of p27-mislocalized cells in vitro. Similar results were observed in other cancer cell lines known to have the p27 mislocalization, suggesting PAK1 is a common and potential downstream effector of p27-mediated metastasis. An experimental metastasis mouse model further showed that a PAK1-silenced mutant had a significant impairment in the development of pulmonary metastasis. In summary, our study indicates that cytoplasmic p27 is a novel prognostic biomarker in OS. In the tumor cell, the mislocalization activates PAK1-mediated cell motility and metastasis. Targeting PAK1 in metastatic OS harboring the p27 mislocalization may be exploited as a potential therapeutic intervention to improve the poor outcome of the affected children.

Citation Format: Xiang Chen, Justin Cates, Yuchen Du, Yun Jung Sung, Xiao-nan Lo, John Hicks, Tsz-Kwong Man. p21-activated kinase 1 is a novel therapeutic target for metastatic osteosarcoma harboring p27 mislocalization [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2876.

Immunohistochemical analysis of the Wnt/β-catenin signaling pathway in pancreatic neuroendocrine neoplasms

AIM: To investigate the role of the Wnt/β-catenin pathway in pancreatic neuroendocrine neoplasms (PanNENs).

METHODS: Tissue microarrays containing 88 PanNENs were immunohistochemically labeled with antibodies to β-catenin, E-cadherin, adenomatous polyposis coli (APC), chromogranin and synaptophysin. One case had only metastatic tumors resected, whereas others (n = 87) received pancreatectomy with or without partial hepatectomy. Pathology slides, demographic, clinicopathologic, and follow up data were reviewed. Patients’ demographics, clinicopathologic features, and immunohistochemical results from 87 primary tumors were compared between patients with low stage (stage I/II) and high stage (stage III/IV) tumors. In addition, correlation of immunohistochemical results from primary tumors with disease-specific survival (DSS) was evaluated.

RESULTS: Strong membranous β-catenin staining in the primary tumor was observed in all 13 stage III/IV PanNENs as compared to 47% (35/74) of stage I/II tumors (P < 0.01). However, the strong membranous β-catenin staining was unassociated with tumor grade or DSS. Decreased membranous β-catenin staining was associated with decreased membranous E-cadherin labeling. Nuclear β-catenin staining was seen in 15% (2/13) of stage III/IV PanNENs as compared to 0% (0/74) of stage I/II tumors (P = 0.02). The case with metastasectomy also only showed nuclear β-catenin staining. Two of the three cases with nuclear β-catenin staining were familial adenomatous polyposis (FAP) patients. Lack of APC expression was seen in 70% (57/81) of the cases, including the 3 cases with nuclear β-catenin staining. Expression of E-cadherin and APC in primary tumor was not correlated with tumor grade, tumor stage, or disease specific survival.

CONCLUSION: The Wnt/β-catenin pathway was altered in some PanNENs, but did not Impact DSS. PanNENs in FAP patients demonstrated nuclear β-catenin accumulation and loss of APC.

Abstract 853: Novel quantitative multiplexed PD-1/PD-L1 immunohistochemistry test provides superior prediction of treatment response in melanoma patients

While PD-1/L1 axis-targeted therapies have shown promising clinical responses, their use in combination therapies is associated with both benefits and safety concerns. Response rates for single-agent anti-PD-1 therapies are significantly higher in biomarker positive patients, therefore there is a need to utilize predictive diagnostics to enhance benefit-risk profiles and guide treatment decisions. To address this, we developed a novel quantitative multiplexed immunohistochemistry assay that provides objective quantitation of PD-L1 positive cells, but more importantly assesses interactions with immune cells (PD-1+ or CD8+) in formalin-fixed paraffin embedded (FFPE) clinical specimens. The clinical validity of this assay was verified in a small series of melanoma patients treated with anti-PD1 targeted therapies/agents.

FFPE melanoma tissues from patients who received anti-PD-1 therapy were fluorescently stained with a combination of anti-PD-1, PD-L1, and S100 antibodies plus DAPI or a combination of anti-CD8, PD-L1, and S100 antibodies plus DAPI. Each slide was then imaged on Vectra platform and the frequencies of biomarker positive cells (PD-L1, PD-1, and CD8) and their interaction scores were objectively evaluated using proprietary Automated Quantitative Analysis (AQUA®) algorithms. Analytical sensitivity, precision, and accuracy were established using standardized PD-L1 and PD-1 tissue control arrays composed of cell lines and lymphoid organs, while range of biomarker expression was verified on archived melanoma clinical specimens (n = 30), including samples taken from melanoma patients prior to anti-PD-1 therapies (n = 21).

Frequencies of PD-L1 positive cells could be accurately quantified within 1% to 100% range in predefined control cell line mixtures. PD-L1 and PD-1 measurements were highly reproducible (R2 = 0.98 and 0.97, respectively). A broad range of PD-L1 and PD-1 expression and interaction scores were observed in archival clinical specimens (n = 53). In a cohort of 21 advanced melanoma patients treated with nivolumab (n = 5) or pembrolizumab (n = 16), the PD-1/L1 interaction score was found to reliably distinguish responders from non-responders (p = 0.03) while PD-L1 alone (p = 0.15) or CD-8 alone (p = 0.23) did not. Additionally, patients exhibiting higher PD-1/L1 interaction scores had superior response rates (78% vs. 17%, p = 0.03). Responders experienced significantly longer median progression-free survival (177 vs. 85 days, p = 0.014), and fewer deaths (22% vs 58%) compared with patients having lower PD-1/L1 interaction scores.

In terms of diagnostic utility, the PD-1/L1 multiplex test showed superior predictive power (78% Positive Predictive Value, 83% Negative Predictive Value) compared with PD-L1 expression alone. Additional studies are underway to fully establish diagnostic utility and aid in treatment guidance.

Citation Format: Jennifer Bordeaux, Douglas Johnson, Jeffrey Sosman, Ju Young Kim, Christine Vaupel, Bashar Dabbas, Justin Cates, Jeff Hall, Jelveh Lameh, Shabnam Tangri, Naveen Dakappagari. Novel quantitative multiplexed PD-1/PD-L1 immunohistochemistry test provides superior prediction of treatment response in melanoma patients. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 853.

Enhancer of zeste homolog 2 (EZH2) expression in bladder cancer

BACKGROUND

Studies evaluating enhancer of zeste homolog 2 (EZH2) expression and oncologic outcomes in bladder cancer have been discrepant. EZH2 expression in noninvasive bladder cancer is not well studied. We thus set out to address the discrepancy in previous reports, and to study expression of EZH2 in noninvasive bladder cancer and its associations, in a large cystectomy cohort.

MATERIALS AND METHODS

EZH2 expression was evaluated in tissue microarray material (invasive and noninvasive cancer). Associations between EZH2 expression and oncologic outcomes, tumor stage, and disease type were determined. Receiver operating characteristic analysis was performed for EZH2 expression in the diagnosis of invasive carcinoma and flat carcinoma in situ (CIS) compared to benign urothelium.

RESULTS

EZH2 expression was most common in CIS, followed by invasive carcinoma, noninvasive papillary urothelial carcinoma, and benign urothelium, in decreasing order (P<0.05 all comparisons, linear model). The receiver operating characteristic analysis demonstrated an area under the curve of 0.92 for CIS and 0.83 for invasive carcinoma, both compared to benign urothelium. At a cutoff of≥4, this corresponded to sensitivities of 89% and 73%, and specificities of 82% and 82%, for CIS and invasive carcinoma, respectively. The EZH2 expression was not associated with oncologic outcomes, including recurrence-free survival and death from bladder cancer. The EZH2 expression status (positive or negative) of noninvasive and invasive carcinomas taken from the same bladder correlated (P = 0.05, Fisher exact).

CONCLUSION

That EZH2 status of noninvasive and invasive cancer correlated in individual patients suggests that EZH2 may be a marker of lineage. EZH2 may offer diagnostic utility, particularly in flat urothelial CIS vs. benign urothelium. The present study supports that EZH2 expression in bladder cancer is not predictive of oncologic outcome.

Inhibition of Wnt/β-catenin pathway promotes regenerative repair of cutaneous and cartilage injury

Wound healing in mammals is a fibrotic process. The mechanisms driving fibrotic (as opposed to regenerative) repair are poorly understood. Herein we report that therapeutic Wnt inhibition with topical application of small-molecule Wnt inhibitors can reduce fibrosis and promote regenerative cutaneous wound repair. In the naturally stented model of ear punch injury, we found that Wnt/β-catenin pathway is activated most notably in the dermis of the wound bed early (d 2) after injury and subsides to baseline levels by d10. Topical application of either of 2 mechanistically distinct small-molecule Wnt pathway inhibitors (a tankyrase inhibitor, XAV-939, and the U.S. Food and Drug Administration-approved casein kinase activator, pyrvinium) in C57Bl/6J mice resulted in significantly increased rates of wound closure (72.3 ± 14.7% with XAV-939; and 52.1 ± 20.9% with pyrvinium) compared with contralateral controls (38.1 ± 23.0 and 40.4.± 16.7%, respectively). Histologically, Wnt inhibition reduced fibrosis as measured by α-smooth muscle actin positive myofibroblasts and collagen type I α1 synthesis. Wnt inhibition also restored skin architecture including adnexal structures in ear wounds and dermal-epidermal junction with rete pegs in excisional wounds. Additionally, in ear punch injury Wnt inhibitor treatment enabled regeneration of auricular cartilage. Our study shows that pharmacologic Wnt inhibition holds therapeutic utility for regenerative repair of cutaneous wounds.

Abstract A12: Genetic and pharmacologic inhibition of EPHA2 promotes apoptosis in NSCLC

Genome-wide analyses determined previously that the receptor tyrosine kinase (RTK) EPHA2 is commonly overexpressed in non-small cell lung cancers (NSCLCs). EPHA2 overexpression is associated with poor clinical outcomes; therefore, EPHA2 may represent a promising therapeutic target for patients with NSCLC. In support of this hypothesis, we have shown that targeted disruption of EPHA2 in a murine model of aggressive KRAS-mutant NSCLC impairs tumor growth. Knockdown of EPHA2 in human NSCLC cell lines reduced cell growth and viability, confirming the epithelial cell autonomous requirements for EPHA2 in NSCLCs. Targeting EPHA2 in NSCLCs decreased S6K1-mediated phosphorylation of cell death agonist BAD and induced apoptosis. Furthermore, an ATP-competitive EPHA2 RTK inhibitor, ALW-II-41-27, reduced the number of viable NSCLC cells in a time-dependent and dose-dependent manner in vitro and induced tumor regression in human NSCLC xenografts in vivo. Collectively, these data demonstrate a role for EPHA2 in the maintenance and progression of NSCLCs and provide evidence that ALW-II-41-27 effectively inhibits EPHA2-mediated tumor growth in preclinical models of NSCLC.

Citation Format: Katherine Amato, Shan Wang, Andrew Hastings, Victoria Youngblood, Pranav Santapuram, Haiying Chen, Justin Cates, Daniel Colvin, Fei Ye, Dana Brantley-Sieders, Rebecca Cook, Li Tan, Nathanael Gray, Jin Chen. Genetic and pharmacologic inhibition of EPHA2 promotes apoptosis in NSCLC. [abstract]. In: Proceedings of the AACR Special Conference: Targeting the PI3K-mTOR Network in Cancer; Sep 14-17, 2014; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(7 Suppl):Abstract nr A12.

Low levels of tumor necrosis factor alpha increase tumor growth by inducing an endothelial phenotype of monocytes recruited to the tumor site

Microenvironmental cues instruct infiltrating tumor-associated myeloid cells to drive malignant progression. A subpopulation of tumor-associated myeloid cells coexpressing endothelial and myeloid markers, although rare in peripheral blood, are primarily associated with tumors where they enhance tumor growth and angiogenesis. These biphenotypic vascular leukocytes result from the endothelial differentiation of myeloid progenitors, a process regulated by tumor necrosis factor (TNF)alpha in vitro. An in vivo increase in tumor-derived TNFalpha expression promoted tumor growth and vascularity of mouse melanoma, lung cancer, and mammary tumors. Notably, tumor growth was accompanied by a significant increase in myeloid/endothelial biphenotypic populations. TNFalpha-associated tumor growth, vascularity, and generation of tumor vascular leukocytes in mouse melanoma tumors were dependent on intact host TNFalpha receptors. Importantly, TNFalpha-expressing tumors did not exhibit increased inflammation over control tumors, suggesting a unique action related to myeloid to endothelial differentiation. Our studies suggest that TNFalpha constitutes a tumor microenvironment signal that biases recruited monocytes toward a proangiogenic/provasculogenic myeloid/endothelial phenotype.

Intracortical chondroma simulating osteoid osteoma treated by radiofrequency

Two children presented with painful lytic lesions in the lower extremity. The lesions were located within cortical bone, and surrounded by sclerosis of the medullary bone and periosteal new bone formation. The lesions were painful, and nonsteroidal anti-inflammatory agents relieved the pain. CT-guided core biopsies were performed followed by radiofrequency treatment. Pathologic evaluation of the specimens revealed features consistent with benign intracortical chondroma. In one case radiofrequency treatment appears to have cured the tumor. The other patient required operative intervention.

Surgical treatment of hemangiomas of soft tissue

Hemangioma is one of the most common soft tissue tumors comprising 7% of all benign tumors. The etiology is unclear. Many treatment modalities for the symptomatic deep subdermal or intramuscular hemangioma have been used, but surgical excision is the preferred treatment. During the past 20 years, 89 patients with soft tissue hemangiomas were treated by surgical excision at the authors' institution. This study was done to define the clinical characteristics of pathologically proven hemangiomas and to evaluate the outcome of the operative procedures. Intralesional or marginal excision for symptomatic hemangiomas yields satisfactory results for pain relief, functional recovery, and avoidance of recurrence. According to the data a hemangioma of the soft tissues is a benign lesion in which more aggressive surgery (wide or radical excision) or other modalities such as radiation usually are not warranted.

Diffuse bile duct tumors: guidelines for management

The majority of patients with bile duct cancer have small focal adenocarcinomas localized to the upper, middle, or lower third of the bile duct. In contrast, a small subgroup of patients have been identified with bile duct tumors that are diffuse, involving multiple segments of the extrahepatic biliary tract. Among 186 patients with documented bile duct cancer treated at the UCLA Medical Center between 1954 and 1988, 13 patients (7%) had diffuse lesions. Patients with diffuse tumors had markedly poorer survival rates than did those with focal lesions. As diffuse tumors are not amenable to resection, surgical management consists primarily of establishing suitable biliary drainage. All patients with bile duct cancer should undergo careful intraoperative evaluation to exclude a diffuse lesion before tumor resection.

Gastrointestinal complications after cardiac transplantation: a spectrum of diseases

Cardiac transplantation has become an accepted treatment modality for end-stage cardiac failure. The gastrointestinal (GI) tract represents a potential source of posttransplant morbidity and mortality. To define the scope of this problem, records of all patients undergoing cardiac transplantation at UCLA between January 1984 and July 1989 were reviewed. In all, there were 120 patients (90 males and 30 females) with a mean age of 45.4 yr. Among them, there were 61 patients (51%) who developed a total of 112 posttransplant GI complications. Of the entire 120 patients, 41 (34%) developed minor complications and 20 (17%) sustained major GI morbidity. Eighteen patients (15%) underwent either endoscopy or surgical intervention. These data suggest that most cardiac transplant recipients will experience some form of GI complication, although most are minor and can be managed conservatively. However, when major, life-threatening complications occur, evaluation and intervention should proceed expeditiously. The gastroenterologist and GI surgeon should play complimentary roles in the care of these complicated patients.

Heterogeneity of [3H]estradiol binding sites in the rat prostate: properties and distribution of type I and type II sites

In order to assess the rat prostate as a target tissue for receptor-mediated estrogen action, we have studied the properties and distributions of estrogen binding sites in the dorsolateral (DLP) and ventral (VP) prostate. Saturation analyses over a wide range of [3H]estradiol ([3H]E2) concentrations (0.5-100 nM) revealed two distinct types of binding sites in the cytosol and nuclear fractions of DLP of intact rats. The high affinity (type I) estrogen binding sites saturated at 2-4 nM of [3H]E2 and had a capacity of 170 fmol/mg DNA in the cytosol and 400 fmol/mg DNA in the nuclei. DLP type I sites had ligand specificity similar to that described for the classical estrogen receptors (ERs) found in female target tissues. The moderate affinity (type II) estrogen binding sites saturated at 15-30 nM of [3H]E2 and had a capacity of 850 fmol/mg DNA in the cytosol and 1600 fmol/mg DNA in the nuclei. DLP type II sites shared some characteristics of the type II ERs described for the rat uterus; they were estrogen specific, heat labile, and sensitive to reducing agents such as dithiothreitol. Saturation analyses on VP cytosols and nuclear fractions revealed only high affinity sites but no moderate affinity sites in the tissue preparations. Our finding that prostatic type II estrogen binding sites are present exclusively in the DLP supports the concept that basic biological differences exist between the two major prostatic lobes of the rat. Furthermore, our findings may help elucidate the observed differences in susceptibility between these two lobes to the hormonal induction of proliferative prostatic lesions.