Artificial Intelligence Reveals Distinct Prognostic Subgroups of Muscle-Invasive Bladder Cancer on Histology Images.

Muscle-invasive bladder cancer (MIBC) is a highly heterogeneous and costly disease with significant morbidity and mortality. Understanding tumor histopathology leads to tailored therapies and improved outcomes. In this study, we employed a weakly supervised learning and neural architecture search to develop a data-driven scoring system. This system aimed to capture prognostic histopathological patterns observed in H&E-stained whole-slide images. We constructed and externally validated our scoring system using multi-institutional datasets with 653 whole-slide images. Additionally, we explored the association between our scoring system, seven histopathological features, and 126 molecular signatures. Through our analysis, we identified two distinct risk groups with varying prognoses, reflecting inherent differences in histopathological and molecular subtypes. The adjusted hazard ratio for overall mortality was 1.46 (95% CI 1.05-2.02; z: 2.23; p = 0.03), thus identifying two prognostic subgroups in high-grade MIBC. Furthermore, we observed an association between our novel digital biomarker and the squamous phenotype, subtypes of miRNA, mRNA, long non-coding RNA, DNA hypomethylation, and several gene mutations, including FGFR3 in MIBC. Our findings underscore the risk of confounding bias when reducing the complex biological and clinical behavior of tumors to a single mutation. Histopathological changes can only be fully captured through comprehensive multi-omics profiles. The introduction of our scoring system has the potential to enhance daily clinical decision making for MIBC. It facilitates shared decision making by offering comprehensive and precise risk stratification, treatment planning, and cost-effective preselection for expensive molecular characterization.

Efficient Augmented Intelligence Framework for Bladder Lesion Detection.

PURPOSE: Development of intelligence systems for bladder lesion detection is cost intensive. An efficient strategy to develop such intelligence solutions is needed. MATERIALS AND METHODS: We used four deep learning models (ConvNeXt, PlexusNet, MobileNet, and SwinTransformer) covering a variety of model complexity and efficacy. We trained these models on a previously published educational cystoscopy atlas (n = 312 images) to estimate the ratio between normal and cancer scores and externally validated on cystoscopy videos from 68 cases, with region of interest (ROI) pathologically confirmed to be benign and cancerous bladder lesions (ie, ROI). The performance measurement included specificity and sensitivity at frame level, frame sequence (block) level, and ROI level for each case. RESULTS: Specificity was comparable between four models at frame (range, 30.0%-44.8%) and block levels (56%-67%). Although sensitivity at the frame level (range, 81.4%-88.1%) differed between the models, sensitivity at the block level (100%) and ROI level (100%) was comparable between these models. MobileNet and PlexusNet were computationally more efficient for real-time ROI detection than ConvNeXt and SwinTransformer. CONCLUSION: Educational cystoscopy atlas and efficient models facilitate the development of real-time intelligence system for bladder lesion detection.

A magnetic hydrogel for the efficient retrieval of kidney stone fragments during ureteroscopy.

Only 60-75% of conventional kidney stone surgeries achieve complete stone-free status. Up to 30% of patients with residual fragments <2 mm in size experience subsequent stone-related complications. Here we demonstrate a stone retrieval technology in which fragments are rendered magnetizable with a magnetic hydrogel so that they can be easily retrieved with a simple magnetic tool. The magnetic hydrogel facilitates robust in vitro capture of stone fragments of clinically relevant sizes and compositions. The hydrogel components exhibit no cytotoxicity in cell culture and only superficial effects on ex vivo human urothelium and in vivo mouse bladders. Furthermore, the hydrogel demonstrates antimicrobial activity against common uropathogens on par with that of common antibiotics. By enabling the efficient retrieval of kidney stone fragments, our method can lead to improved stone-free rates and patient outcomes.

Randomized controlled trial investigating use of submucosal injection of EverLift™ in rates of complete resection of non-pedunculated 4-9 mm polyps.

INTRODUCTION: Currently, cold snare polypectomy (CSP) without submucosal injection is recommended for removing polyps < 10 mm. Use of viscous submucosal agents has not been previously evaluated in CSP. We investigate the potential role of EverLift™ (GI Supply, Pennsylvania) in CSP. METHODS: The study is a single-center prospective randomized non-inferiority clinical trial evaluating CSP of non-pedunculated 4-9 mm polyps, with or without submucosal injection of EverLift™. Patients 18-80 years of age presenting for colonoscopy were recruited. Eligible polyps underwent block randomization to CSP with or without EverLift™. Following CSP, two biopsies were performed at the CSP site margin. The primary non-inferiority outcome was complete resection rate, defined by absence of residual polyp in the margin biopsies (non-inferiority margin -10%). RESULTS: A total of 291 eligible polyps underwent CSP, with 142 removed using EverLift™. There was similar polyp size and distribution of pathology between the two groups. Overall, there was a low rate of positive margins with (1.4%) or without submucosal injection (2.8%), with no significant difference in complete resection (difference 1.28%, 95% CI: -2.66 to 5.42%), demonstrating non-inferiority of EverLift™ injection. Use of EverLift™ significantly increased CSP time (109.8 vs 38.8 s, p < 0.0001) and frequency of use of hemostatic clips (13.4 vs 3.6%, p = 0.002). CONCLUSION: Submucosal injection of EverLift™ was non-inferior to CSP of 4-9 mm polyps without injection and increased time for resection as well as use of hemostatic clips to control acute bleeding. Our results suggest that polypectomy of 4-9 mm polyps can be safely performed without submucosal injection of EverLift™.

Randomized Controlled Trial Investigating Cold Snare and Forceps Polypectomy Among Small POLYPs in Rates of Complete Resection: The TINYPOLYP Trial.

INTRODUCTION: Optimizing complete resection during colonoscopy is important because residual neoplastic tissue may play a role in interval cancers. The US Multi-Society Task Force recommends diminutive (≤5 mm) and small (6-9 mm) polyps be removed by cold snare polypectomy (CSP). However, evidence is less clear whether CSP retains significant advantage over cold forceps polypectomy (CFP) for polyps ≤3 mm. METHODS: This study is a single-center prospective noninferiority randomized clinical trial evaluating CFP and CSP for nonpedunculated polyps ≤3 mm. Patients 18 years and older undergoing colonoscopy for any indication were recruited. During each colonoscopy, polyps underwent block randomization to removal with CFP or CSP. After polypectomy, 2 biopsies were taken from the polypectomy margin. The primary noninferiority outcome was the complete resection rate, defined by absence of residual polyp in the margin biopsies. RESULTS: A total of 179 patients were included. Patients had similar distribution in age, sex, race/ethnicity, as well as indication of procedure. A total of 279 polyps ≤3 mm were identified, with 138 in the CSP group and 141 in the CFP group. Mean polypectomy time was longer for CSP compared with CFP (42.3 vs 23.2 seconds, P < 0.001), although a higher proportion of polyps removed by CFP were removed in more than 1 piece compared with CSP (15.6 vs 3.6%, P < 0.001). There were positive margin biopsies in 2 cases per cohort, with a complete resection rate of 98.3% in both groups. There was no significant difference in cohorts in complete resection rates (difference in complete resection rates was 0.057%, 95% confidence interval: -4.30% to 4.53%), demonstrating noninferiority of CFP compared with CSP. DISCUSSION: Use of CFP was noninferior to CSP in the complete resection of nonpedunculated polyps ≤3 mm. CSP required significantly more time to perform compared with CFP. CFP should be considered an acceptable alternative to CSP for removal of polyps ≤3 mm.

Immunohistochemical Characterization of 120 Testicular Sex Cord-Stromal Tumors With an Emphasis on the Diagnostic Utility of SOX9, FOXL2, and SF-1.

Sex cord-stromal tumors (SCSTs) account for the second most common category of testicular neoplasms and include several entities that may show overlapping morphologies and present diagnostic challenges. We analyzed a cohort of 120 testicular SCSTs and investigated the diagnostic utility of SRY-box transcription factor 9 (SOX9), forkhead box protein L2 (FOXL2), and steroidogenic factor 1 (SF-1) immunohistochemical stains. The results were compared with the more commonly used SCST markers, inhibin α, calretinin, and Wilms' tumor 1 (WT1). SF-1 was overall the most sensitive stain (91%), followed by inhibin α (70%), calretinin (52%), FOXL2 (50%), SOX9 (47%), and WT1 (37%), but sensitivities varied by tumor type. SOX9 and calretinin were more commonly positive in sex cord elements versus stromal elements (62% vs. 27% and 47% vs. 9%, respectively), whereas FOXL2 was more commonly positive in stromal elements versus sex cord elements (100% vs. 55%) when excluding Leydig cell tumors from the stromal category. Although no individual stain was diagnostically specific, some immunophenotypic patterns were noted that may help in the subclassification of SCSTs. We conclude that SOX9, FOXL2, and SF-1 are useful immunohistochemical stains for confirming sex cord-stromal differentiation in testicular tumors and provide increased sensitivity as well as additional diagnostic information, especially when combined with the more commonly used inhibin α, calretinin, and WT1 immunostains. Although morphology is paramount for subclassification of SCSTs, knowledge of certain immunohistochemical patterns may be helpful for diagnostically challenging cases.

Immunohistochemical ALK Expression in Granular Cell Atypical Fibroxanthoma: A Diagnostic Pitfall for ALK-Rearranged Non-neural Granular Cell Tumor.

ABSTRACT: Atypical fibroxanthoma (AFX) is a neoplasm that most commonly occurs on sun-damaged skin of the head and neck in elderly patients and that usually exhibits indolent clinical behavior with complete excision. The granular cell variant of AFX demonstrates overlapping histopathologic features with dermal non-neural granular cell tumor (NNGCT), which typically arises on the extremities of young to middle aged adults with rare reports of regional metastasis. A subset of NNGCT harbors ALK rearrangements and expresses ALK by immunohistochemistry. Here, we present 2 cases of granular cell AFX occurring on the scalp of males aged 73 and 87 with ALK expression by immunohistochemistry and no evidence of an ALK rearrangement on fluorescence in situ hybridization, representing a diagnostic pitfall for NNGCT.

Metastatic squamous cell carcinoma transformed from prostatic adenocarcinoma following androgen deprivation therapy: A case report with clinicopathologic and molecular findings.

Squamous cell carcinoma (SCC) of the prostate is a rare and clinically aggressive entity that may arise de novo or through transformation of prostatic adenocarcinoma, typically following hormonal or radiation therapy. Confirmation of prostatic origin, especially when evaluating a metastatic focus, often requires correlation with clinical and imaging findings, as the morphologic and immunohistochemical features of SCC are not organ-specific. Comprehensive genomic profiling (CGP) may provide additional information useful for confirming the primary site and for identifying potential targeted therapy options. CGP data may also contribute to our understanding of the molecular basis of squamous differentiation in prostatic malignancies. However, these data are limited, and to our knowledge, there are only three previously published cases of prostatic SCC with reported CGP findings. Herein, we report a case of metastatic keratinizing SCC diagnosed by core needle biopsy in a 68-year-old man with a history of prostatic adenocarcinoma status post radical prostatectomy and androgen deprivation therapy (ADT). NKX3.1 immunohistochemistry was negative. CGP was performed, and a TMPRSS2-ERG fusion, among other genetic alterations, was detected, supporting a diagnosis of metastatic SCC transformed from prostatic adenocarcinoma following ADT. This case supports the use of CGP or other molecular techniques not only to query potential targeted therapy options but also to refine the diagnosis and confirm the primary site of disease in cases with non-specific morphologic and immunophenotypic features, such as SCC.

A Clinicopathologic and Molecular Analysis of Fumarate Hydratase-deficient Renal Cell Carcinoma in 32 Patients.

Fumarate hydratase-deficient renal cell carcinoma (FH-deficient RCC) is a rare and recently described entity associated with hereditary leiomyomatosis and RCC syndrome. FH-deficient RCC may show variable clinical and pathologic findings, but commonly presents with locally advanced and metastatic disease and carries a poor prognosis. We identified 32 patients with FH-deficient RCC, confirmed by FH immunohistochemistry (IHC) and/or FH mutation analysis, and performed a retrospective review of the clinical and pathologic features. Median age at presentation was 43 years (range, 18 to 69 y), and the M:F ratio was 2.2:1. Median tumor size was 6.5 cm (range, 2.5 to 28 cm), and 71% presented at stage ≥pT3a. After a median follow-up of 16 months (range, 1 to 118 mo) in 26 patients, 19% showed no evidence of disease, 31% were alive with disease, and 50% were dead of disease. The vast majority of cases showed multiple histologic growth patterns, with papillary (52%) being the most common predominant pattern, followed by solid (21%), cribriform/sieve-like (14%), sarcomatoid (3%), tubular (3%), cystic (3%), and low-grade oncocytic (3%). Viral inclusion-like macronucleoli with perinucleolar clearing were present in almost all cases (96%). All cases were evaluated using FH IHC, and 3 cases (9%) showed retained FH expression. Nineteen cases had germline or tumor mutation analysis confirming a FH mutation, with 79% (11/14) of cases showing mutations within coding regions and 21% (3/14) showing mutations within intronic splice-sites. By IHC, 97% (32/33) of cases were negative for CK7, 93% (27/29) were negative for p63, and 52% (15/29) were negative for GATA3. All cases stained were positive for PAX8 and showed retained succinate dehydrogenase B expression. Our overall findings show that FH-deficient RCC is considerably heterogenous in morphology and frequently behaves aggressively. Suspicion for this entity should be raised even in the absence of predominantly papillary architecture and characteristic nucleolar features. We have included cases with uncommonly seen features, including 4 cases with predominantly cribriform/sieve-like architecture as well as one case with pure low-grade oncocytic morphology (9 y of clinical follow-up without evidence of disease). Although FH IHC is a useful tool for identifying cases of FH-deficient RCC, not all cases of FH-deficient RCC show loss of FH staining, and FH mutation analysis should be considered for patients with suspicious clinical or pathologic features, even in cases with retained FH IHC expression.

Targeted deep sequencing of cell-free DNA in serous body cavity fluids with malignant, suspicious, and benign cytology.

BACKGROUND: Liquid biopsy using cell-free DNA (cfDNA) presents new opportunities for solid tumor genotyping. While studies have demonstrated the utility of cfDNA from plasma, cfDNA from other body fluids remains underexplored. METHODS: We evaluated the molecular features and clinicopathologic correlates of cfDNA from serous body cavity fluids by performing hybrid capture-based next-generation sequencing (NGS) on cfDNA isolated from residual effusion supernatants. Twenty-one serous effusions from pleural (n = 15), peritoneal (n = 5), and pericardial (n = 1) cavity were analyzed. RESULTS: The supernatants provided a median cfDNA concentration of 10.3 ng/µL. Notably, all effusions were sequenced successfully to a median depth >1000×, revealing a broad range of genetic alterations including single nucleotide variants, small insertions and deletions, amplifications, and fusions. Specifically, pathogenic alterations were identified in all malignant fluids (13/13), all fluids suspicious for malignancy (2/2), and 1 benign fluid (1/6) from a patient with metastatic cancer. To validate our findings, we examined matching results from 11 patients who underwent additional testing using formalin-fixed, paraffin-embedded (FFPE) specimens. In 8 patients, the paired results between FFPE and supernatant testing were concordant, whereas in the remaining 3 patients, supernatant analysis identified additional variants likely associated with resistance to targeted therapies. Additional comparison between FFPE and supernatant testing showed no difference in DNA concentration (P = .5), depth of coverage (P = .6), or allele frequency of pathogenic mutations (P = .7). CONCLUSION: cfDNA isolated from serous body cavity fluids represents a promising source of genomic input for targeted NGS.

Evaluation of diagnostic accuracy and a practical algorithmic approach for the diagnosis of renal masses by FNA.

BACKGROUND: The classification of renal neoplasms is essential for oncologic risk stratification and clinical management, and an accurate pretreatment pathologic diagnosis can provide useful guidance for active surveillance, minimally invasive ablative therapy, or surgical resection and can reduce the incidence of overtreatment. Previous studies evaluating the diagnostic accuracy of fine-needle aspiration (FNA) and core-needle biopsy (CNB) for renal masses are limited and show variable results. METHODS: Two hundred forty-seven renal FNA cases with or without concurrent CNB performed and/or reviewed at the Stanford University School of Medicine over the course of 20 years were identified. Cytohistopathologic correlation was performed for 77 cases with subsequent resection specimens. All available case materials were reviewed, and select cases were worked up further and reclassified as necessary. RESULTS: Cytohistopathologic correlation showed 96% diagnostic specificity and 83% sensitivity for renal FNA with or without concurrent CNB. Discordant cases were mostly attributed to sampling errors or suboptimal specimens (79%) and also included 2 non-renal cell carcinoma entities (1 case of angiomyolipoma and 1 case of a benign peripheral nerve sheath tumor) and 1 case involving misclassification of the renal cell carcinoma subtype. CONCLUSIONS: There is considerable value in FNA/CNB for the initial diagnosis of renal masses because of the high diagnostic specificity and sensitivity. Sensitivity is predominantly dependent on sufficient sampling, and additional potential diagnostic pitfalls include nonepithelial and rare entities. Judicious use of ancillary techniques is encouraged, especially when one is presented with a limited specimen, and this article presents a practical algorithmic approach to the diagnosis of renal masses using salient morphologic features and results from ancillary studies. Fine-needle aspiration is an accurate method for the diagnosis of renal masses. A practical diagnostic algorithm, based on salient morphologic and ancillary findings, is presented.

Flow immunophenotyping of benign lymph nodes sampled by FNA: Representative with diagnostic pitfalls.

BACKGROUND: Fine-needle aspiration with flow cytometry (FNA-FC) is routinely used in the evaluation of lymph nodes suspicious for lymphoma, yet data comparing immunophenotype distributions and outliers in benign lymph nodes sampled by fine-needle aspiration (FNA) versus excision are lacking. METHODS: Flow cytometry data from 289 benign lymph node FNA cases were assessed for the overall antigen distribution, with a focus on outliers relevant to the diagnosis of lymphoma. Distributions and outlier proportions were compared with those of a separate cohort of 298 excisional biopsies. RESULTS: Compared with excisional biopsies, FNA specimens overrepresented CD3+ events (72% vs 63%), underrepresented CD19+ events (22% vs 29%), and had 25% fewer large cell-gated events. Normalized antigen distributions in FNA were equivalent to those in excisional biopsy. Twenty-three percent of FNA-FC cases exhibited an outlier, including a skewed kappa:lambda light-chain ratio, increased CD5+ or CD10+ B-cell events, a skewed CD4:CD8 ratio, and increased CD7 loss on T cells, with no significant differences in frequency or type in comparison with excisional specimens. Outliers for the light-chain ratio and T-cell antigens were enriched among older patients and included patients with a variety of autoimmune/rheumatologic conditions. CONCLUSIONS: Benign lymph node FNA yields flow immunophenotypes remarkably similar to those from excisional biopsies. Outlier flow immunophenotypes are identified in benign lymph nodes sampled by FNA at a frequency similar to that with excisional biopsies. Older patients, who have a higher baseline risk of lymphoma, are more likely to exhibit lymphoma-mimicking outliers such as a light-chain predominance on B cells and skewed CD4:CD8 ratios or increased CD7 loss on T cells, and they warrant additional diagnostic caution.

An integrated flow cytometry analysis of 286 mature B cell neoplasms identifies CD13 as a useful marker for diagnostic subtyping.

INTRODUCTION: CD13 is a myeloid associated antigen, which may be expressed by a subset of B cell lymphomas; however, the significance of its expression along with other B cell associated antigens is not well characterized. METHODS: Two hundred and eighty-six mature B cell neoplasms with flow cytometric analysis performed at the time of diagnosis were identified. Expression of CD13, CD45, CD19, CD20, CD5, CD10, CD38, CD22, CD23, FMC7, and kappa and lambda light chains was assessed for each case and correlated with clinicopathologic features. RESULTS: CD13 expression was associated specifically with cases of lymphoplasmacytic lymphoma (LPL) (16/26)- and FMC7-positive chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) (11/30). No cases of follicular lymphoma (FL) expressed CD13 (0/48). Across all B cell neoplasms, CD13 expression positively correlated with FMC7 co-expression and kappa light chain restriction and negatively correlated with CD10 co-expression and lambda light chain restriction. No significant association of CD13 with overall or disease free survival in B cell neoplasms was seen. CONCLUSION: CD13 expression is present more often in LPL- and FMC7-positive CLL/SLL than other mature B cell lymphoma subtypes and absent in cases of FL and may be a useful feature for diagnostic subtyping.

Cardiovascular pathology in 2 young adults with sudden, unexpected death due to coronary aneurysms from Kawasaki disease in childhood.

PURPOSE: Coronary artery aneurysms (CAA) may remain silent after Kawasaki disease (KD) until adulthood when myocardial ischemia can lead to sudden death. We postulated that there would be young adults with sudden, unexpected death due to CAA from KD who would have a state-mandated autopsy performed by the San Diego County Medical Examiner's Office (SDCMEO). METHODS: We reviewed all autopsy cases <35years of age from 1997 to 2012 at the SDCMEO with a cardiovascular cause of death (n=154). RESULTS: We found 2 cases meeting inclusion criteria. Case 1 was a 22-year-old Korean male with chronic ischemic changes due to a partially occluded and diffusely calcified 15mm aneurysm at the bifurcation of the left main coronary artery. Interview of the mother revealed that this patient had been diagnosed with KD complicated by giant aneurysms at age two years. Case 2 was a 30-year-old Hispanic male with myocardial infarction due to thrombosis of a calcified left anterior descending artery aneurysm. Histologic findings included diffuse myocardial fibrosis and a recanalized aneurysm in the right coronary artery. Interview of the family revealed a KD-compatible illness in childhood. Immunohistochemical staining showed expression of transforming growth factor ß pathway molecules in the aneurysmal arterial wall. CONCLUSIONS: In a medical examiner's office serving a population of approximately 3 million people, 2 of 154 (1.3%) cardiovascular deaths in persons <35years were attributed to cardiovascular complications of KD in childhood. Antecedent KD should be considered in the evaluation of all cases of sudden, unexpected death in young adults.

Differential expression of miR-145 in children with Kawasaki disease.

BACKGROUND: Kawasaki disease is an acute, self-limited vasculitis of childhood that can result in structural damage to the coronary arteries. Previous studies have implicated the TGF-ß pathway in disease pathogenesis and generation of myofibroblasts in the arterial wall. microRNAs are small non-coding RNAs that modulate gene expression at the post-transcriptional level and can be transported between cells in extracellular vesicles. To understand the role that microRNAs play in modifying gene expression in Kawasaki disease, we studied microRNAs from whole blood during the acute and convalescent stages of the illness. METHODOLOGY/PRINCIPAL FINDINGS: RNA isolated from the matched whole blood of 12 patients with acute and convalescent Kawasaki disease were analyzed by sequencing of small RNA. This analysis revealed six microRNAs (miRs-143, -199b-5p, -618, -223, -145 and -145* (complementary strand)) whose levels were significantly elevated during the acute phase of Kawasaki disease. The result was validated using targeted qRT-PCR using an independent cohort (n = 16). miR-145, which plays a critical role in the differentiation of neutrophils and vascular smooth muscle cells, was expressed at high levels in blood samples from acute Kawasaki disease but not adenovirus-infected control patients (p = 0.005). miR-145 was also detected in small extracellular vesicles isolated from acute Kawasaki disease plasma samples. Pathway analysis of the predicted targets of the 6 differentially expressed microRNAs identified the TGF-ß pathway as the top pathway regulated by microRNAs in Kawasaki disease. CONCLUSION: Sequencing of small RNA species allowed discovery of microRNAs that may participate in Kawasaki disease pathogenesis. miR-145 may participate, along with other differentially expressed microRNAs, in regulating expression of genes in the TGF-ß pathway during the acute illness. If the predicted target genes are confirmed, our findings suggest a model of Kawasaki disease pathogenesis whereby miR-145 modulates TGF-ß signaling in the arterial wall.