A future directions of renal cell carcinoma treatment: combination of immune checkpoint inhibition and carbon ion radiotherapy.

Renal cell carcinoma (RCC) is considered radio- and chemo-resistant. Immune checkpoint inhibitors (ICIs) have demonstrated significant clinical efficacy in advanced RCC. However, the overall response rate of RCC to monotherapy remains limited. Given its immunomodulatory effects, a combination of radiotherapy (RT) with immunotherapy is increasingly used for cancer treatment. Heavy ion radiotherapy, specifically the carbon ion radiotherapy (CIRT), represents an innovative approach to cancer treatment, offering superior physical and biological effectiveness compared to conventional photon radiotherapy and exhibiting obvious advantages in cancer treatment. The combination of CIRT and immunotherapy showed robust effectiveness in preclinical studies of various tumors, thus holds promise for overcoming radiation resistance of RCC and enhancing therapeutic outcomes. Here, we provide a comprehensive review on the biophysical effects of CIRT, the efficacy of combination treatment and the underlying mechanisms involved in, as well as its therapeutic potential specifically within RCC.

Insulinoma Unmasked Post Sleeve Gastrectomy With Incidental Renal Cell Carcinoma: A Rare Case.

Insulinoma is a functional pancreatic neuroendocrine tumor (pNET). Usually benign and solitary, these tumors present with recurrent episodes of hypoglycemia due to insulin hypersecretion. It's a rare cause of post bariatric surgery hypoglycemia and hence poses a diagnostic challenge. Here, we report the first case of a 53-year-old male with insulinoma unmasked post sleeve gastrectomy with incidental renal cell carcinoma (RCC). He presented with symptoms of Whipple's triad after two months of sleeve gastrectomy done for morbid obesity. On further inquiry, the patient gave a history of an asymptomatic peripancreatic neuroendocrine tumor (NET) for the past 11 years. With a suspicion of insulinoma, biochemical workup followed by non-invasive imaging like GA-68 DOTA and CT triphasic abdomen scan was done to guide the diagnosis of an insulinoma which also detected a second primary tumor in the right kidney, likely to be a malignant RCC. Following pancreatic mass excision with radical nephrectomy for right renal mass, histopathology (HPE) and immunohistochemistry (IHC) confirmed the diagnosis of an insulinoma and a right renal clear cell carcinoma. The patient was discharged with no further episodes of hypoglycemia. Hence, persistent hypoglycemia post bariatric surgery could be an indication of a hidden insulinoma and this possibility of synchronous tumors should be kept in mind when dealing with rare tumors like insulinoma.

Renomedullary Interstitial Cell Tumor in the Background of a Renal Oncocytoma: A Case Report.

Renomedullary interstitial cell tumors (RMICTs) are rare benign renal tumors that arise from the renal medulla. They are rarely symptomatic and are mostly discovered incidentally. Radiologically, their co-presence ipsilaterally in the background of a larger mass introduces a miscellaneous presentation that raises the suspicion of metastatic disease. A characteristic presentation does not exist. Therefore, an individualized, patient-centered approach should be tailored depending on the nature of the presentation. We report the clinical, radiological, and histopathological presentation of a 46-year-old woman presenting with an RMICT in the background of a renal oncocytoma.

Immunotherapy Applications for Thymine Dimers and WT1 Antigen in Renal Cancers: A Comparative Statistical Analysis.

Renal cell carcinoma (RCC) remains incurable in advanced stages. Biomarkers have proven to be quite useful in cancer therapeutics. Herein, we provide a comparative/integrative statistical analysis of seminal immunohistochemistry (IHC) findings for Wilms' Tumor 1 antigen (WT1) and thymine dimers (TDs), emerging as atypical, yet promising, potential biomarkers for RCCs. We assessed WT1/TD reactivity in adult RCC tumor cells, tumor microenvironment (TME), and tumor-adjacent healthy renal tissue (HRT). WT1 positivity was scarce and strictly nuclear in tumor cells, whereas TD-reactive tumor tissues were prevalent. We report statistically significant positive correlations between the density of reactive RCC cellularity and the intensity of nuclear staining for both biomarkers (WT1 - rho = 0.341, p-value = 0.036; TDs - rho = 0.379, p-value = 0.002). RCC stromal TME TD-positivity was much more frequent than WT1 reactivity, apparently proportional to that of the proper RCC cellularity and facilitated by extensive RCC inflammatory infiltration. TDs exhibited nuclear reactivity for most TME cell lines, while RCC TME WT1 expression was rare and inconsistent. In HRTs, TDs were entirely restricted to renal tubular cells, the likely cellular progenitor of most conventional RCC subtypes. In lieu of proper validation, these early findings have significant implications regarding the origins/biology of RCCs and may inform RCC therapeutics, both accounting for the high frequency of immunotherapy-permissive frameshift indels in RCCs, but also hinting at novel predictive clinical tools for WT1-targeted immunotherapy. Overall, the current study represents a meek yet hopefully significant step towards understanding the molecular biology and potential therapeutic targets of RCCs.

Renal Cell Carcinoma in a Patient With Crossed Renal Ectopia: A Case Report.

Crossed fused renal ectopia (CFRE) is a rare congenital anomaly in which a kidney is located on the opposite side from where its ureter connects to the bladder, merging into the other kidney. It has been linked to other rare congenital malformations, including the VACTERL association (vertebral anomalies, anal atresia, cardiac anomalies, tracheoesophageal fistula, esophageal atresia, renal anomalies, and limb abnormalities), the MURCS association (müllerian ducts, renal, and cervicothoracic spine anomalies), increased incidence of infections, obstruction, cystic dysplasia, and urolithiasis. Although the literature has documented only a small number of cases wherein CFRE coincides with neoplasia, we present the case of a 59-year-old patient with a right ectopic kidney fused to the left one and simultaneous primary renal cell carcinoma. We aim to report and discuss this case and the treatment approach, comparing it with existing literature to enhance our understanding and management of similar occurrences, as partial nephrectomy is uncommon due to the challenging anatomy of these cases.

Predicting EGFR Status After Radical Nephrectomy or Partial Nephrectomy for Renal Cell Carcinoma on CT Using a Self-attention-based Model: Variable Vision Transformer (vViT).

OBJECTIVE: To assess the effectiveness of the vViT model for predicting postoperative renal function decline by leveraging clinical data, medical images, and image-derived features; and to identify the most dominant factor influencing this prediction. MATERIALS AND METHODS: We developed two models, eGFR10 and eGFR20, to identify patients with a postoperative reduction in eGFR of more than 10 and more than 20, respectively, among renal cell carcinoma patients. The eGFR10 model was trained on 75 patients and tested on 27, while the eGFR20 model was trained on 77 patients and tested on 24. The vViT model inputs included class token, patient characteristics (age, sex, BMI), comorbidities (peripheral vascular disease, diabetes, liver disease), habits (smoking, alcohol), surgical details (ischemia time, blood loss, type and procedure of surgery, approach, operative time), radiomics, and tumor and kidney imaging. We used permutation feature importance to evaluate each sector's contribution. The performance of vViT was compared with CNN models, including VGG16, ResNet50, and DenseNet121, using McNemar and DeLong tests. RESULTS: The eGFR10 model achieved an accuracy of 0.741 and an AUC-ROC of 0.692, while the eGFR20 model attained an accuracy of 0.792 and an AUC-ROC of 0.812. The surgical and radiomics sectors were the most influential in both models. The vViT had higher accuracy and AUC-ROC than VGG16 and ResNet50, and higher AUC-ROC than DenseNet121 (p < 0.05). Specifically, the vViT did not have a statistically different AUC-ROC compared to VGG16 (p = 1.0) and ResNet50 (p = 0.7) but had a statistically different AUC-ROC compared to DenseNet121 (p = 0.87) for the eGFR10 model. For the eGFR20 model, the vViT did not have a statistically different AUC-ROC compared to VGG16 (p = 0.72), ResNet50 (p = 0.88), and DenseNet121 (p = 0.64). CONCLUSION: The vViT model, a transformer-based approach for multimodal data, shows promise for preoperative CT-based prediction of eGFR status in patients with renal cell carcinoma.

The role of natural products versus miRNA in renal cell carcinoma: implications for disease mechanisms and diagnostic markers.

Natural products are chemical compounds produced by living organisms. They are isolated and purified to determine their function and can potentially be used as therapeutic agents. The ability of some bioactive natural products to modify the course of cancer is fascinating and promising. In the past 50 years, there have been advancements in cancer therapy that have increased survival rates for localized tumors. However, there has been little progress in treating advanced renal cell carcinoma (RCC), which is resistant to radiation and chemotherapy. Oncogenes and tumor suppressors are two roles played by microRNAs (miRNAs). They are involved in important pathogenetic mechanisms like hypoxia and epithelial-mesenchymal transition (EMT); they control apoptosis, cell growth, migration, invasion, angiogenesis, and proliferation through target proteins involved in various signaling pathways. Depending on their expression pattern, miRNAs may identify certain subtypes of RCC or distinguish tumor tissue from healthy renal tissue. As diagnostic biomarkers of RCC, circulating miRNAs show promise. There is a correlation between the expression patterns of several miRNAs and the prognosis and diagnosis of patients with RCC. Potentially high-risk primary tumors may be identified by comparing original tumor tissue with metastases. Variations in miRNA expression between treatment-sensitive and therapy-resistant patients' tissues and serum allow for the estimation of responsiveness to target therapy. Our knowledge of miRNAs' function in RCC etiology has a tremendous uptick. Finding and validating their gene targets could have an immediate effect on creating anticancer treatments based on miRNAs. Several miRNAs have the potential to be used as biomarkers for diagnosis and prognosis. This review provides an in-depth analysis of the current knowledge regarding natural compounds and their modes of action in combating cancer. Also, this study aims to give information about the diagnostic and prognostic value of miRNAs as cancer biomarkers and their involvement in the pathogenesis of RCC.

Brown Tumor From Secondary Hyperparathyroidism Mimicking Metastatic Renal Cell Carcinoma in a Patient With End-Stage Renal Disease.

Brown tumors (also known as osteitis fibrosa cystica) are rare complications of end-stage renal disease (ESRD) and secondary hyperparathyroidism (HPT), characterized by focal bone lesions that resemble neoplasms. They are often misdiagnosed as metastatic bone disease, especially in patients with a history of malignancy. We present a case of a 60-year-old man with a history of renal cell carcinoma (RCC), and ESRD on hemodialysis (HD), who developed diffuse bone lesions on imaging with osteolytic/osteoblastic appearance concerning metastases, but on further workup was found to have brown tumors. We discuss the treatment and outcome and briefly review the relevant medical literature.

Bovine Meat and Milk Factor-like Sequences Are Frequently Detected in Renal Cell Carcinoma Tissues.

Previous studies have indicated a potential role of diet in the pathogenesis of renal cell carcinoma (RCC). Recently, circular bovine meat and milk factor (BMMF) DNAs have been identified in peritumoral tissues of human colon and breast cancers. Here, we investigated the prevalence of the DNA of these novel human pathogenic infectious agents in RCC and adjacent peritumoral renal tissues. DNA was extracted from formalin-fixed and paraffin-embedded (FFPE) RCC and peritumoral kidney tissues, including a test (n = 11) and a validation (n = 152) collection. BMMF1 and BMMF2 consensus primers were designed to screen for the presence of BMMF1- and BMMF2-like DNA. In addition, BMMF-specific PCR was performed on selected cases to test for the presence of additional regions of BMMF1 and BMMF2 genomes. A reference collection of hepatocellular carcinomas (HCCs; n = 60) and adjacent peritumoral liver tissues (n = 50) was also included. Our results demonstrated that BMMF1 and BMMF2 DNAs are frequently found in human RCC tissues and are particularly more prevalent in peritumoral kidney tissues. Of note, BMMF1 and BMMF2 genotype heterogeneity was higher in peritumoral kidney tissues compared to RCC tissues. This is the first study to directly test human FFPE tissues for BMMF1- and BMMF2-like DNA using consensus PCR and demonstrate BMMF DNA in neoplastic and peritumoral kidney tissues. The findings are in line with the recently proposed indirect etiopathogenetic role of BMMFs in, e.g., colorectal carcinogenesis. Follow-up studies are needed to explore the potential role of BMMFs in the etiopathogenesis of RCC.

Optical biomarker analysis for renal cell carcinoma obtained from preoperative and postoperative patients using ATR-FTIR spectroscopy.

Renal cell carcinoma (RCC) is the most common malignant tumor in the urinary system, accounting for 80 % to 90 % for all renal malignancies. Traditional diagnostic methods like magnetic resonance imaging (MRI) and computed tomography (CT) lack the sensitivity and specificity as they lack specific biomarkers. These limitations impede effective monitoring of tumor recurrence. This study aims to employ Attenuated Total Reflection (ATR)-Fourier transform infrared (FTIR) spectroscopy, an optical technology sensitive to molecular groups, to analyze the potential optical biomarkers in urine and plasma samples from RCC patients pre- and post-surgery. The results reveal distinctive spectral information from both plasma and urine samples. Post-surgery urine spectra exhibit complexity compared to plasma, showing reduced content at 1072 cm-1, 1347 cm-1 and 1654 cm-1 bands, while increased content at 1112 cm-1, 1143 cm-1, 1447 cm-1, 3334 cm-1 and 3420 cm-1 bands. Utilizing machine learning models such as eXtreme Gradient Boosting (XGBoost), support vector machine (SVM), partial least squares (PLS), and artificial neural network (ANN), the study evaluated plasma and urine samples pre- and post-surgery. Remarkably, the XGBoost method excelled in distinguishing between tumor conditions and recovery, achieving an impressive AUC value of 0.99. These results underscore the potential of ATR-FTIR technology in identifying RCC optical biomarkers, with XGBoost showing promise as a valuable screening tool for RCC recurrence diagnosis.

Ginsenoside Rh4 Facilitates the Sensitivity of Renal Cell Carcinoma to Ferroptosis via the NRF2 Pathway.

BACKGROUND: Renal cell carcinoma (RCC) is one of the most common malignancies of the urinary system and ferroptosis is considered as a promising therapeutic approach for treating RCC. Ginsenoside Rh4 (Rh4) was proved to have anticancer properties and play roles in ferroptosis. This study aimed to investigate the potential of ginsenoside Rh4 (Rh4) in enhancing the sensitivity of renal cell carcinoma (RCC) cells to ferroptosis and to elucidate the underlying mechanisms. METHODS: RCC cell lines of 786-O and ACHN were treated with RAS-selective lethal 3 (RSL3) and/or Rh4. Cell-viability assays were used to determine how Rh4 affected the sensitivity of RCC cells to RSL3-induced ferroptosis. Quantitative real-time polymerase chain reaction was conducted to examine the levels of ferroptosis-related genes. Additionally, the knockdown of nuclear factor E2-related factor 2 (NRF2) was performed to investigate the role of NRF2 in mediating the effects of Rh4. RESULTS: RSL3 suppressed the progression of RCC cells by inducing ferroptosis. Furthermore, Rh4 led to more RCC sensitivity to ferroptosis induced by RSL3. Rh4 downregulated the ferroptosis-related gene expression including superoxide dismutase 1 (p < 0.01), glutathione peroxidase 4 (p < 0.01), and catalase (p < 0.01), which was attenuated by NRF2 knockdown. This finding suggested that Rh4 exerted its sensitising effect on ferroptosis through the NRF2 pathway. CONCLUSIONS: Rh4 made RCC cells more sensitive to ferroptosis by inhibiting the NRF2 signaling and suppressing the expression of antioxidant enzymes. Therefore, combining Rh4 with ferroptosis-inducing reagents to treat RCC had potential therapeutic application.

Cardiac Challenges in Immune Checkpoint Therapy: Complete Heart Block With Pembrolizumab.

Immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment, yet they come with a spectrum of immune-related adverse events, including cardiac complications. We present the case of a 72-year-old male with metastatic renal cell carcinoma who developed complete heart block and ventricular arrhythmias following pembrolizumab therapy. Despite no evidence of myocarditis, the patient's condition rapidly deteriorated, ultimately resulting in his demise. This case underscores the critical need for vigilance in recognizing and managing potential cardiotoxicity associated with ICIs. Additionally, it highlights the importance of multidisciplinary collaboration in optimizing diagnostic and therapeutic strategies for patients undergoing immune checkpoint inhibitor therapy.

An Atypical Presentation of a Saddle Embolism in the Setting of Malignancy.

A 52-year-old male presented to the emergency room with acute abdominal pain. Imaging determined acute appendicitis, with an incidental finding of a renal mass. The biopsy was positive for renal cell carcinoma, and the patient underwent simultaneous appendectomy and nephrectomy. Postoperatively, the patient developed hypoxia at night with exertion, requiring oxygen supplementation. The remainder of his vital signs were stable. Due to renal function, a ventilation/perfusion (V/Q) scan was conducted, which showed a high probability of pulmonary embolism (PE). Follow-up computed tomography angiography of the chest showed a massive saddle embolism. Interventional radiology performed an uncomplicated thrombectomy, oxygen saturations improved, and the patient was discharged on apixaban.

Effect of lesion dimension on survival in patients with T1a renal cell carcinoma who underwent deferred surgery.

BACKGROUND: Small renal masses (SRMs) have been shown to have low malignant potential. Active surveillance (AS), typically characterized by regular follow-up and delayed nephrectomy if necessary, is recommended as an option for frail patients with SRMs. Nevertheless, the impact of tumor size on survival in T1a RCC patients undergoing delayed nephrectomy for SRMs remains unclear. METHODS: Patients diagnosed with non-metastatic T1a RCC who underwent nephrectomy were identified from the Surveillance, Epidemiology, and End Results (SEER) database and divided into immediate (< 6 months) and delayed nephrectomy (≥ 6 months) groups based on the duration from diagnosis to nephrectomy. After propensity score matching (PSM), overall survival (OS) and cancer-specific survival (CSS) were estimated by K-M curves and compared with log-rank test. RESULTS: A total of 27,502 patients were enrolled, of whom 26,915 (97.9%) received immediate nephrectomy and 587 (2.1%) received delayed nephrectomy. After PSM, 1174 patients who underwent immediate nephrectomy and 587 patients who underwent delayed nephrectomy were included. With a median delay of 7 months, delayed nephrectomy resulted in non-inferior OS for RCC tumors sized 0.1-2.0 cm (HR = 1.12, p = 0.636). However, for RCC tumors sized 2.1-3.0 cm (HR = 1.60, p = 0.008) and 3.1-4.0 cm (HR = 1.89, p < 0.001), delayed nephrectomy showed inferior OS compared to immediate nephrectomy. Delayed nephrectomy did not result in significantly worse CSS than immediate nephrectomy in all tumor size subgroups (all p > 0.05), however this may be due to sample size limiting statistical power. CONCLUSION: Based on the SEER database, we found that with a median delay of 7 months, 2 cm may be an appropriate cut-off point of delayed nephrectomy for patients diagnosed with non-metastatic T1a RCC.

Ginsenoside Rh4 Facilitates the Sensitivity of Renal Cell Carcinoma to Ferroptosis via the NRF2 Pathway

Background: Renal cell carcinoma (RCC) is one of the most common malignancies of the urinary system and ferroptosis is considered as a promising therapeutic approach for treating RCC. Ginsenoside Rh4 (Rh4) was proved to have anticancer properties and play roles in ferroptosis. This study aimed to investigate the potential of ginsenoside Rh4 (Rh4) in enhancing the sensitivity of renal cell carcinoma (RCC) cells to ferroptosis and to elucidate the underlying mechanisms. Methods: RCC cell lines of 786-O and ACHN were treated with RAS-selective lethal 3 (RSL3) and/or Rh4. Cell-viability assays were used to determine how Rh4 affected the sensitivity of RCC cells to RSL3-induced ferroptosis. Quantitative real-time polymerase chain reaction was conducted to examine the levels of ferroptosis-related genes. Additionally, the knockdown of nuclear factor E2-related factor 2 (NRF2) was performed to investigate the role of NRF2 in mediating the effects of Rh4. Results: RSL3 suppressed the progression of RCC cells by inducing ferroptosis. Furthermore, Rh4 led to more RCC sensitivity to ferroptosis induced by RSL3. Rh4 downregulated the ferroptosis-related gene expression including superoxide dismutase 1 (p < 0.01), glutathione peroxidase 4 (p < 0.01), and catalase (p < 0.01), which was attenuated by NRF2 knockdown. This finding suggested that Rh4 exerted its sensitising effect on ferroptosis through the NRF2 pathway. Conclusions: Rh4 made RCC cells more sensitive to ferroptosis by inhibiting the NRF2 signaling and suppressing the expression of antioxidant enzymes. Therefore, combining Rh4 with ferroptosis-inducing reagents to treat RCC had potential therapeutic application. (AU)

Palliative Treatment of Leptomeningeal Carcinomatosis From Renal Cell Carcinoma With Local CyberKnife Radiotherapy and Systemic Pazopanib Therapy: A Case Report.

Leptomeningeal carcinomatosis (LMC) from renal cell carcinoma (RCC) is rare. There is no established treatment strategy for LMC, and the prognosis is extremely poor. We describe a case of LMC from RCC treated with local CyberKnife radiotherapy (CKR) and systemic therapy with pazopanib. The patient was a 63-year-old man with brain metastases from right RCC. Surgery and CKR were performed for the brain metastases, and the lesions were subsequently controlled. The patient developed isolated lesions in the pituitary stalk, right internal auditory canal, left ventricular choroid plexus (CP), left facial nerve, and medulla oblongata after the surgery and CKR for brain metastases. We diagnosed LMC and treated the patient with systemic therapy with pazopanib. We performed local therapy with CKR for lesions of the pituitary stalk, right internal auditory canal, left facial nerve, and medulla oblongata. The CP lesion was not treated with CKR because the lesion tended to shrink after systemic therapy with pazopanib. There were no symptoms due to LMC until the end of life and no adverse events due to CKR. Ten years and five months after the nephrectomy for RCC, one year and four months after the initial CKR for brain metastases, and nine months after the diagnosis of LMC, the patient died due to pleural effusion from lung metastases. Our case suggests that CKR combined with pazopanib may be effective as a palliative treatment for LMC from RCC.