Background: In the past, the airway epithelium was thought to be primarily an inert physical barrier. We now know that the upper airway epithelium plays a critical role in both innate and adaptive immunity, and that epithelial dysfunction is strongly associated with inflammatory airway disease. The pathogenesis of chronic rhinosinusitis is poorly understood, but growing evidence supports a key role for the airway epithelium in the pathophysiology of the disease. Objective: The purpose of this study is to explore our current understanding of how dysfunction in human sinonasal epithelial cells (HSNECs) contributes to the pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP) and to examine how current and developing therapies affect epithelial cell functions. Methods: A literature review of papers published in English pertaining to epithelial cell dysfunction in patients with CRSwNP was performed using the PubMed database. The search utilized combinations of the following key words: sinusitis, polyps, epithelium, pathophysiology, barrier function, dendritic cells, eosinophils, T cells, complement, mucociliary clearance, vitamin D, cytokines, chemokines, taste receptors, steroids, saline, and therapy. Results: HSNEC mucociliary clearance, barrier function, secretion of cytokines, influence on dendritic cells, influence on T-cells, regulation of eosinophils, vitamin D metabolism, complement production, and taste receptor function are altered in patients with CRSwNP and contribute to the pathogenesis of the disease. Current therapies utilized to manage CRSwNP counteract the effects of HSNEC dysfunction and relieve key symptoms of the disease. Conclusion: HSNECs are key players in both innate and adaptive immunity, and altered epithelial functions are closely intertwined with the pathogenesis of CRSwNP. Our review supports further investigation of altered HSNEC function in patients with CRSwNP and supports development of novel epithelial-targeted therapies for its management.

(1) Background: Recent studies report high accuracies when using machine learning (ML) algorithms to classify prostate cancer lesions on publicly available datasets. However, it is unknown if these trained models generalize well to data from different institutions. (2) Methods: This was a retrospective study using multi-parametric Magnetic Resonance Imaging (mpMRI) data from our institution (63 mpMRI lesions) and the ProstateX-2 challenge, a publicly available annotated image set (112 mpMRI lesions). Residual Neural Network (ResNet) algorithms were trained to classify lesions as high-risk (hrPCA) or low-risk/benign. Models were trained on (a) ProstateX-2 data, (b) local institutional data, and (c) combined ProstateX-2 and local data. The models were then tested on (a) ProstateX-2, (b) local and (c) combined ProstateX-2 and local data. (3) Results: Models trained on either local or ProstateX-2 image data had high Area Under the ROC Curve (AUC)s (0.82–0.98) in the classification of hrPCA when tested on their own respective populations. AUCs decreased significantly (0.23–0.50, p < 0.01) when models were tested on image data from the other institution. Models trained on image data from both institutions re-achieved high AUCs (0.83–0.99). (4) Conclusions: Accurate prostate cancer classification models trained on single-institutional image data performed poorly when tested on outside-institutional image data. Heterogeneous multi-institutional training image data will likely be required to achieve broadly applicable mpMRI models.

Renal cell carcinoma (RCC) is considered to be the deadliest urologic cancer with high rates of metastasis and recurrence after nephrectomy. RCC can metastasize to nearly any organ but most commonly metastasizes to the liver, lung, brain, and bone. To date, there are only about 40 reported cases of RCC with solitary bladder metastasis. The following report contributes to this limited data set of patients with RCC who develop solitary metastasis to the bladder. A 69-year-old male presented with occasional gross hematuria and was found to have a left renal mass infiltrating the collecting system. Ureteroscopic biopsy revealed clear cell RCC, and the patient subsequently underwent radical left nephrectomy. Eight months after nephrectomy, the patient presented to the clinic with gross hematuria. In-office cystoscopy demonstrated a nodular lesion in the bladder arising from the left ureteral orifice. The patient underwent transurethral resection of the bladder mass and pathology demonstrated clear cell RCC. Subsequent imaging showed no evidence of metastatic disease. Five months after transurethral resection, the patient was found to have a left distal ureteral mass and underwent left ureterectomy with partial cystectomy. Pathology again demonstrated clear cell RCC. RCC with solitary metastasis to the bladder is rare, and there are no targeted guideline recommendations for management. Per standard of care, patients with painless hematuria and risk factors for malignancy should undergo cystoscopy. In patients with a history of RCC, metastasis to the bladder should be considered in the differential diagnosis. Patients with metastatic RCC to the bladder should undergo a thorough work-up for additional sites of metastasis. In patients with RCC who develop solitary bladder metastasis amenable to resection following nephrectomy, there is a lack of evidence to guide therapy and a multidisciplinary discussion is warranted. However, if the tumor is amenable to resection, metastasectomy is a reasonable therapeutic approach and offers the patient an improved quality of life and an opportunity for remission.

Traumatic pelvic arteriovenous fistulas (AVFs) are exceedingly rare and can lead to significant morbidity. Herein, we describe the case of a 31 year-old male who presented with two months of recurrent gross hematuria following a gluteal gun-shot wound and was found to have a right internal iliac AVF. To our knowledge, this is the first reported case of a post traumatic pelvic AVF presenting with gross hematuria.