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Summary The spectrum of neuroendocrine (NE) tumors in the genitourinary tract ranges from the aggressive large and small cell carcinomas to the often benign paraganglioma and well-differentiated neuroendocrine tumor (WD-NET). At least 15 pure lower urinary tract (LUT) WD-NETs have been described. Owing to the rarity of WD-NET in the LUT and the limited number of reported cases, a better definition of their biologic long-term behavior is warranted. Herein, we aim to describe 10 new cases of WD-NET arising in the LUT and expand on follow-up findings. Ten consultation cases were identified and included 6 men and 4 women who ranged from 45 to 73 years of age. Seven cases arose in the bladder with one located in the bladder neck, 1 arose in the prostatic urethra, 1 arose in the female urethra, and 1 arose in the left ureteral orifice. All lesions were confined to the lamina propria, and tumor architecture was pseudoglandular in all cases. Associated cystitis cystica et glandularis was identified in 5 cases; urothelial papilloma and florid von Brunn's nests were found in 2 additional cases. Immunohistochemical staining for synaptophysin and chromogranin was diffusely positive in 9 cases and focal in 1 case, and the Ki-67 proliferation index was 5% or less in all tumors. Follow-up ranged from 37 to 137 months (mean = 82; median = 77), and there was no evidence of residual disease or recurrence in any of the 10 patients during the follow-up period.

The Cancer Genome Atlas project introduced genomic taxonomy of basal and luminal molecular subtypes in muscle invasive bladder cancer. Fewer studies have addressed the molecular classification in non-muscle invasive bladder cancer (NMIBC). Our aim is to assess the applicability of the proposed phenotypic classification for NMIBC. Three TMAs were constructed from 193 TURBT specimens of 60 bladder cancer patients treated at one of the authors' institutions (1998-2008). Follow-up data on recurrence, grade, or stage progression was obtained. Immunohistochemistry was performed using an automated Ventana System for markers indicative of luminal (GATA3, CK20, ER, Uroplakin II, and HER2/neu) and basal (CK5/6 and CD44) phenotype. Marker expression was evaluated by 3 urologic pathologists. Using unadjusted logistic regression, we found significant association between tumor recurrence at next biopsy and CD44 expression (OR = 2.51, P = 0.03), tumor recurrence at any subsequent biopsy and ER expression (OR = 0.24, P = 0.04), and tumor grade progression at any subsequent biopsy and HER2/neu expression (OR = 0.24, P = 0.04). After adjusting for pathologic stage, we found a significant association between CK5/6 expression and tumor stage progression at either next or any subsequent biopsy (OR = 0.94, P = 0.006; and OR = 0.97, P = 0.02, respectively). Our findings suggest that individual immunohistochemical markers may be of value as prognostic factors in NMIBC.

Background: The PD-1/PD-L1 signaling axis is currently the most elucidated mechanism for tumor evasion of T-cell-mediated immunity. Nevertheless, few data are available regarding its impact on cervical cancer and the relationship with lymphocytic infiltrates. Methods: A retrospective assessment of all cases of cervical neoplasia treated in Caxias do Sul General Hospital, Brazil, between 2012 and 2016 was performed. Clinical and pathological data were collected from electronic records and analyzed. Original slides were independently reviewed by three pathologists to confirm diagnoses and to assess the immunohistochemical expression of PD-L1 and FoxP3 in tumor cells and lymphocytic infiltrates. Results: PD-L1 staining was present in 32.2% of the 59 cervical samples. Median overall survival time of the PD-L1-negative group was 47.8 months, a time point not yet reached by the PD-L1-positive group (p=0.968). Median progression-free survival was 24.3 months for PD-L1-negative and 11.5 months for PD-L1-positive patients (p=0.263). PD-L1 staining was found in 27.1% of the lymphocytic infiltrates, and survival analysis revealed no difference between PD-L1-positive and PD-L1-negative samples. There was no impact on survival related to FoxP3 staining in neither tumor samples nor lymphocytic infiltrates. Conclusion: Although the median progression-free survival times differed, the difference was not statistically significant. Our study corroborates the rationale that PD-L1 expression in cervical neoplasms has no impact on survival. PD-L1 expression in peritumoral lymphocytes revealed no impact on infiltration volume nor survival. Keywords: uterine cervical neoplasms, tumor-infiltrating lymphocytes, cancer, tumor microenvironment, survival.

Noninvasive approaches for early detection of bladder cancer are actively being investigated. We recently developed a urine- based molecular assay for the detection and surveillance of bladder neoplasms (UroSEEK). UroSEEK is designed to detect alterations in 11 genes that include most common genetic alterations in bladder cancer. In this study, we analyzed 527 cases, including 373 noninvasive and 154 invasive urothelial carcinomas of bladder from transurethral resections or cystectomies performed at four institutions (1991–2016). Two different mutational analysis assays of a representative tumor area were performed: first, a singleplex PCR assay for evaluation of the TERT promoter region (TERTSeqS) and second, a multiplex PCR assay using primers designed to amplify regions of interest of 10 (FGFR3, PIK3CA, TP53, HRAS, KRAS, ERBB2, CDKN2A, MET, MLL, and VHL) genes (UroSeqS). Overall, 92% of all bladder tumors were positive for at least one genetic alteration in the UroSEEK panel. We found TERT promoter mutations in 77% of low-grade noninvasive papillary carcinomas, with a relatively lower incidence of 65% in high-grade noninvasive papillary carcinomas and carcinomas in situ; p = 0.017. Seventy-two percent of pT1 and 63% of muscle-invasive bladder tumors harbored TERT promoter mutations with g.1295228C>T alteration being the most common in all groups. FGFR3 and PIK3CA mutations were more frequent in low-grade noninvasive papillary carcinomas compared with high-grade noninvasive papillary carcinomas and carcinomas in situ (p

Osteogenic differentiation is rarely seen in melanomas, when it occurs it is mainly in acral lesions. We report a case of an osteogenic melanoma in a 49-year-old woman who presented with a pigmented lesion in the subungueal region of her left hallux. The lesion was ulcerated and infiltrated until the deep dermis without bone involvement. The tumor was composed of pleomorphic atypical epithelioid and fusiform cells disposed in nests or cords, with vesicular nuclei and prominent central nucleoli. Focal lentiginous proliferation of large atypical melanocytes was present along the dermoepidermal junction. Areas of osteoid matrix focally mineralized were disposed in trabeculae, and there were islands of neoplastic cells. Immunohistochemistry revealed strong expression of S-100 protein and, unexpectedly, of desmin. Focal expression of Melan-A, microphthalmia transcription factor, and HMB-45 is also revealed. Mutations in BRAF and NRAS genes were not present. The patient was submitted to an amputation of the left hallux with negative sentinel lymph node. The importance of recognizing osteogenic melanoma is based on difficulties for histologic recognition and its differentials diagnosis.

Our group and others have previously demonstrated the presence of TERT promoter mutations (TERT-mut) in 60–80% of urothelial carcinomas and some of their histologic variants. Five other genes have been frequently implicated in bladder cancer: FGRF3, TP53, PIK3CA, HRAS, and CDKN2A. In the current study, we sought to determine the prevalence of mutations in TERT and these five other genes in de novo papillary urothelial neoplasms of low malignant potential (PUNLMP) of the urinary bladder. A retrospective search of our archives for PUNLMP was performed and 30 de novo cases were identified and included in the study. We found mutations in TERT (TERT-mut) and FGFR3 (FGFR3-mut) to be the most common alterations in the cohort (63 and 60%, respectively). The majority of the TERT-mut-positive tumors (84%) had a g.1295228C > T alteration with the remaining tumors demonstrating g.1295250C > T. Approximately one fourth of tumors had TP53 mutations. These findings support the potential utility of a uniform genetic mutation panel to detect bladder cancers of various subtypes.

Urine cytology is an essential element of the diagnostic work up of hematuria. A significant proportion of cases continue to be placed in the “atypical” or “suspicious” categories of the Paris system for urine cytology, posing difficulty in patient management. We report on the performance of our recently described urine-based assay “UroSEEK” in cases with equivocal diagnosis in patients who are investigated for bladder cancer. Urine samples were collected from two cohorts. The first consisted of patients who presented with hematuria or lower urinary tract symptoms (early detection cohort) and the second of patients that are in follow-up for prior bladder cancer (surveillance cohort). Urine samples were analyzed for mutations in 11 genes and aneuploidy. In the early detection setting, we found high sensitivity and specificity (96% and 88%, respectively) and a strong negative predictive value of 99%. The assay performance was less robust in the surveillance cohort (sensitivity of 74%, specificity of 72%, and negative predictive value of 53%). UroSEEK demonstrated a notable lead time to cancer diagnosis. Seven cases in the early detection cohort and 71 surveillance cases were detected at least 6 months prior to clinical diagnosis. Our results suggest a potential role for UroSEEK assay in guiding management of patients with atypical urine cytology if confirmed in future prospective trials.

Vulvar squamous cell carcinoma accounts for 5% of cancers of the female genital tract. Current guidelines recommend wide local excision with negative surgical margins as the standard treatment. However, the extent of the tumor-free resection margin after wide local excision is still controversial in many cases. Drugs targeting immune checkpoints such as PD-1 or its ligand PD-L1 have potential clinical utility in these patients. We examined the expression of PD-L1 in tumor cells and immune cells, as well as the proportion of PD-1, CD8, and FOXP3 positive lymphocytes. Twenty-one cases of invasive vulvar squamous cell carcinomas were reviewed. Whole slides of representative formalin-fixed, paraffin-embedded archival material were used for analysis. Odds ratios (OR) and hazard ratios (HR) were used to estimate risk for disease recurrence, overall mortality, and cancer mortality. PD-L1 expression was found in 43% of tumor cells, with higher proportions in intratumoral (67%) and peritumoral (81%) immune cells. OR and HR for disease recurrence and cancer mortality were higher in tumors with higher CD8 expression. OR and HR for overall mortality were also higher in tumors with higher PD-L1 and CD8 expression. In conclusion, nearly half of cases were PD-L1 positive in tumor cells with over two-third of cases demonstrating PD-L1 positivity in immune cells. Immunohistochemical expression of PD-L1 and CD8 could be used to suggest higher risk of disease recurrence, overall mortality, and cancer mortality. Furthermore, our data contributes to the growing evidence that targeting the PD-1/PD-L1 pathway may be beneficial in vulvar squamous cell carcinomas.

Background: The PD-1/PD-L1 signaling axis is currently the most elucidated mechanism for tumor evasion of T-cell-mediated immunity. Nevertheless, few data are available regarding its impact on cervical cancer and the relationship with lymphocytic infiltrates. Methods: A retrospective assessment of all cases of cervical neoplasia treated in Caxias do Sul General Hospital, Brazil, between 2012 and 2016 was performed. Clinical and pathological data were collected from electronic records and analyzed. Original slides were independently reviewed by three pathologists to confirm diagnoses and to assess the immunohistochemical expression of PD-L1 and FoxP3 in tumor cells and lymphocytic infiltrates. Results: PD-L1 staining was present in 32.2% of the 59 cervical samples. Median overall survival time of the PD-L1-negative group was 47.8 months, a time point not yet reached by the PD-L1-positive group (p=0.968). Median progression-free survival was 24.3 months for PD-L1-negative and 11.5 months for PD-L1-positive patients (p=0.263). PD-L1 staining was found in 27.1% of the lymphocytic infiltrates, and survival analysis revealed no difference between PD-L1-positive and PD-L1-negative samples. There was no impact on survival related to FoxP3 staining in neither tumor samples nor lymphocytic infiltrates. Conclusion: Although the median progression-free survival times differed, the difference was not statistically significant. Our study corroborates the rationale that PD-L1 expression in cervical neoplasms has no impact on survival. PD-L1 expression in peritumoral lymphocytes revealed no impact on infiltration volume nor survival. Keywords: uterine cervical neoplasms, tumor-infiltrating lymphocytes, cancer, tumor microenvironment, survival

Current non-invasive approaches for detection of urothelial cancers are suboptimal. We developed a test to detect urothelial neoplasms using DNA recovered from cells shed into urine. UroSEEK incorporates massive parallel sequencing assays for mutations in 11 genes and copy number changes on 39 chromosome arms. In 570 patients at risk for bladder cancer (BC), UroSEEK was positive in 83% of those who developed BC. Combined with cytology, UroSEEK detected 95% of patients who developed BC. Of 56 patients with upper tract urothelial cancer, 75% tested positive by UroSEEK, including 79% of those with non-invasive tumors. UroSEEK detected genetic abnormalities in 68% of urines obtained from BC patients under surveillance who demonstrated clinical evidence of recurrence. The advantages of UroSEEK over cytology were evident in low-grade BCs; UroSEEK detected 67% of cases whereas cytology detected none. These results establish the foundation for a new non-invasive approach for detection of urothelial cancer.

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.

Skene's (periurethral) gland adenocarcinoma is very rare, with only 7 cases reported in the literature. This is the first series of cases on this entity. We describe the histologic, immunohistochemical, and clinical findings of 4 patients with Skene's gland adenocarcinoma retrieved from the Johns Hopkins Urologic Pathology Consult Service from 1984 to 2017. The average age at diagnosis of the 4 women was 74.5 years (range, 61 to 87 y). Tumors were treated by limited resections with negative margins. Tumor size ranged from 1.0 to 2.0 cm (mean, 1.5 cm). Average follow-up time was 40.7 months (range, 4 to 132 mo). Three of our cases were morphologically consistent with prostatic acinar adenocarcinoma with variable cribriform, fused, and poorly formed glands, analogous to Gleason score 4+4=8. Of these, one had mixed ductal features with neoplastic cells showing papillary carcinoma with columnar cytology. These 3 lesions were positive for PSA, P501S, NKX3.1, and AMACR. Focal goblet cells positive for CK20 and negative for prostatic markers were seen in one of these cases, suggesting intestinal differentiation (although negative for CDX2 and SATB2). A fourth case had glandular and papillary formations with pseudostratified columnar epithelium and mucin secretion, showing positivity for CK7, ER, and P16, and negativity for prostatic markers, suggesting serous differentiation (although negative for PAX8 and WT1). PIN4 cocktail confirmed the origin in preexisting paraurethral glands in 3 of the cases. All patients were alive and free of recurrence or metastatic disease at the time of last follow-up. Because of the rarity of Skene's gland adenocarcinomas, there is no consensus regarding their treatment. Our findings demonstrate that Skene's gland adenocarcinomas recapitulate morphologies and immunohistochemical markers seen in prostatic adenocarcinoma. However, it is unknown whether applying the same grading criteria for prostatic adenocarcinomas to Skene's gland adenocarcinoma is valid given the small number of cases with variable treatment and limited follow-up.

Current non-invasive approaches for detection of urothelial cancers are suboptimal. We developed a test to detect urothelial neoplasms using DNA recovered from cells shed into urine. UroSEEK incorporates massive parallel sequencing assays for mutations in 11 genes and copy number changes on 39 chromosome arms. In 570 patients at risk for bladder cancer (BC), UroSEEK was positive in 83% of those who developed BC. Combined with cytology, UroSEEK detected 95% of patients who developed BC. Of 56 patients with upper tract urothelial cancer, 75% tested positive by UroSEEK, including 79% of those with non-invasive tumors. UroSEEK detected genetic abnormalities in 68% of urines obtained from BC patients under surveillance who demonstrated clinical evidence of recurrence. The advantages of UroSEEK over cytology were evident in low-grade BCs; UroSEEK detected 67% of cases whereas cytology detected none. These results establish the foundation for a new non-invasive approach for detection of urothelial cancer.

The objective was to determine the ablation size of a single 15-min freeze and compare it with the conventional 10-min freeze–8-min thaw–10-min freeze protocol. Secondary objectives were to determine the ablation margin and to ascertain whether islands of viable tissue remain within the ablation zone. Five adult swine under general anesthesia were used. After surgical abdominal exposure, two ablations were performed in liver and two in kidney. One ablation utilized the 15-min and the second the 10–8–10-min protocol. At maximum ice-ball, tissue ink was infused via an angiographic catheter in hepatic or renal artery to stain the non-frozen tissue. Animals were euthanized and organs examined macro- and microscopically. Three histological regions were observed: (A) a viable/stained region representing the tissue outside the ice-ball, (B) a central necrotic area representing the ablated region within the ice-ball and (C) an unstained but viable margin representing the non-lethal margin within ice-ball. Ablation size did not vary with protocol but did for tissue type. Renal ablation was approximately 5 × 4 cm with both protocols, whereas liver ablation was approximately 6.7 × 4.4 cm. Ablation margin was measured at 1 mm irrespective of ablation protocol or tissue. No islands of viable tissue were identified within the ablation zone. Fifteen-minute cryoablation yielded an ablation size and margin identical to that of the conventional 10–8–10-min protocol. Within the ablated region, cell death was uniform. The only difference was a larger cryoablation zone in hepatic tissue compared to renal tissue, likely attributable to differences in blood perfusion.

Follicular dendritic cell (FDC) tumor is an uncommon neoplasm. It generally presents as a slow-growing, painless mass, without systemic symptoms. Histological features usually include low grade spindle cell proliferation. This tumor occurs primarily in lymph nodes, especially cervical and axillary, however, involvement of extranodal sites such as the tonsils, spleen, liver, and gastrointestinal tract has been reported. Inflammatory pseudotumor-like follicular dendritic cell tumor (IPT-like FDCT) is a rare, distinctive histological subtype of this low-grade malignant neoplasm, with consistent Epstein-Barr virus (EBV) association. The differential diagnosis with other fibro-inflammatory tumor proliferations, as inflammatory pseudotumor (IPT) and inflammatory myofibroblastic tumor (IMT), may be challenging. In the present article, two cases of IPT-like FDCT of the spleen are presented, with a broad overview of the literature: one 77-year-old male and one 70-year-old female. A large immunohistochemical panel should be used for diagnosis, as no single specific and totally sensitive markers are available, including markers for CD21, CD23, CD35, CNA42, and clusterin. Individual cases may express one or more of these markers, so that all of them should be investigated. In situ hybridization for EBV is constantly positive. Immunostaining for ALK should be negative, as it is present in roughly half of the cases of IMT. This panel should be used in combination of clinical, laboratory, and topographic evidences. Importantly, inclusion of this lesion as a possible option in clinical and pathological investigation represents the basis for a correct diagnosis.

Current non-invasive approaches for bladder cancer (BC) detection are suboptimal. We report the development of non-invasive molecular test for BC using DNA recovered from cells shed into urine. This “UroSEEK” test incorporates assays for mutations in 11 genes and copy number changes on 39 chromosome arms. We first evaluated 570 urine samples from patients at risk for BC (microscopic hematuria or dysuria). UroSEEK was positive in 83% of patients that developed BC, but in only 7% of patients who did not develop BC. Combined with cytology, 95% of patients that developed BC were positive. We then evaluated 322 urine samples from patients soon after their BCs had been surgically resected. UroSEEK detected abnormalities in 66% of the urine samples from these patients, sometimes up to 4 years prior to clinical evidence of residual neoplasia, while cytology was positive in only 25% of such urine samples. The advantages of UroSEEK over cytology were particularly evident in low-grade tumors, wherein cytology detected none while UroSEEK detected 67% of 49 cases. These results establish the foundation for a new, non-invasive approach to the detection of BC in patients at risk for initial or recurrent disease.

Background Melanocytomas are rare pigmented primary lesions of the central nervous system arising from melanocytes of leptomeninges. They occur most frequently in the posterior fossa, Meckel's cave, or along the cervical and thoracic spinal cord. Orbital melanocytomas have been rarely reported. Nevus of Ota is a melanocytic lesion that can be associated with cutaneous and meningeal melanocytic neoplasms. Methods and Results We describe a case of an orbital melanocytoma associated with ipsilateral Nevus of Ota. A 28-year-old man presented with proptosis and an ipsilateral congenital facial melanocytic lesion (Nevus of Ota). After imaging evaluation, a retro-orbital mass was discovered. A needle biopsy was performed and the diagnosis of melanocytoma rendered. The patient underwent complete surgical excision of the lesion. Conclusion In order to make the correct diagnosis and to choose the appropriate therapy, it is important to be aware of this rare presentation and its association with Nevus of Ota. © 2014 Wiley Periodicals, Inc. Head Neck 37: E49–E55, 2015

Aims GATA3 has been reported as a specific urothelial marker among organs in the pelvic region, and has been classified as highly sensitive and specific for urothelial and breast carcinomas. Our aim was to verify GATA3 expression in extramammary Paget disease, and to determine whether it can be use to differentiate primary vulvar Paget disease from pagetoid urothelial intraepithelial neoplasia (PUIN). We also analysed HER2 protein expression and HER2 gene amplification and their roles as prognostic factors in extramammary Paget disease. Methods and results We analysed GATA3 and HER2 expression in 11 primary vulvar Paget disease cases and two PUIN cases. All cases showed nuclear expression of GATA3. Of 13 cases, five were equivocal for HER2 expression (score 2+) and one was positive (3+). Fluorescence in-situ hybridization results showed amplification in two of these six cases. Both HER2-amplified cases were invasive. Conclusion GATA3 was positive in all extramammary Paget disease cases tested (13 cases), and it has no value for differentiating between primary and secondary vulvar Paget disease from the urological tract. HER2 amplification might confer an aggressive and invasive pattern in primary vulvar Paget disease, as both amplified cases showed an invasive pattern.

e17511Background: Cervical cancer is the 4th most common cause of cancer-related deaths in women worldwide. PD-1 is expressed on tumor-infiltrating lymphocytes (TILs) from many different tumor type...

Urothelial cancer (UC) is a well-known multifocal disease with frequent recurrences. The clonal origin of spatially separated UC foci is controversial. Here we propose to elucidate the multifocal UC genome by next generation sequencing (NGS) and thereby identify novel clonal heterogeneity among the lesions of a single bladder. Until now, all experiments aimed at understanding the molecular heterogeneity were generated mostly by candidate gene approach and older technologies. There is a lack of comprehensive molecular information in these multifocal lesions partly due to inadequate sample size for comprehensive molecular studies. Identification of mutational status at the gene level in different multifocal lesions will allow us to identify markers for prognostic classification, and predictive classification of response to UC therapies, as well as identify potential therapeutic targets. To understand the molecular heterogeneity among the lesions of a single bladder, we used The Ion AmpliSeq™ Comprehensive Cancer Panel (CCP) (ThermoFisher). The Ion AmpliSeq™ CCP was designed to target all exons of 409 key tumor suppressor genes (TSGs) and oncogenes most frequently cited and mutated in cancer. We tested 41 lesions from 16 cystectomized bladders. Among these lesions, we performed an initial analysis of a total of 21 lesions and 8 germ line controls from 8 patients. We further technically validated selected mutational events found by NGS by a complementary approach, namely droplet digital PCR (ddPCR). We then compared the intra- and inter-tumoral mutation profiles. Two separate lesions were used for analysis in 3 patients and 3 lesions were taken from each of the remaining 5 patients. Our initial analysis showed mutational heterogeneity among the lesions of most of the samples. Briefly, two of the patients had one clone found at all sites, while the rest of the patients showed more variation amongst their lesions. For instance, ARID2, TRRAP, PDGFB, and FBXW7 were mutated in two out of three lesions in one of the patients, indicating hotspot for heterogeneous mutational events. Three mutational events were confirmed by ddPCR, denoting the accuracy of our NGS data analysis. Our analysis demonstrates that targeted next generation sequencing is a sensitive and reliable method for interrogating the molecular landscape of bladder cancer, and indicates that both clonal and spontaneous events can account for multifocal bladder cancer. Our data suggests that sequencing of multiple lesions from an individual patient is necessary to accurately elucidate the mutation profile and tailor appropriate targeted treatment. Further analysis in an extended number of samples is necessary to fully understand the molecular heterogeneity at the mutational level in urothelial cancer. Citation Format: Rachel Goldberg, Maria Del Carmen Rodriguez, Leslie Cope, Aline C. Tregnago, Evgeny Izumchenko, George J. Netto, David Sidransky, Mohammad O. Hoque. Spatial genomic heterogeneity of multifocal bladder cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2458. doi:10.1158/1538-7445.AM2017-2458

Melanocytomas are rare pigmented primary lesions of the central nervous system arising from melanocytes of leptomeninges. They occur most frequently in the posterior fossa, Meckel's cave, or along the cervical and thoracic spinal cord. Orbital melanocytomas have been rarely reported. Nevus of Ota is a melanocytic lesion that can be associated with cutaneous and meningeal melanocytic neoplasms.We describe a case of an orbital melanocytoma associated with ipsilateral Nevus of Ota. A 28-year-old man presented with proptosis and an ipsilateral congenital facial melanocytic lesion (Nevus of Ota). After imaging evaluation, a retro-orbital mass was discovered. A needle biopsy was performed and the diagnosis of melanocytoma rendered. The patient underwent complete surgical excision of the lesion.In order to make the correct diagnosis and to choose the appropriate therapy, it is important to be aware of this rare presentation and its association with Nevus of Ota.