Diagnosis Of Renal Cell Carcinoma Research Articles

End-stage renal disease after renal cancer surgery: risk factors and overall survival.

Several risk factors for end-stage renal disease (ESRD), in patients undergoing surgical treatment for renal cell carcinoma (RCC), have been suggested by others. This study aimed to investigate such risk factors and disclose the effect of developing ESRD, postoperatively, on overall survival. The risk of developing ESRD after RCC diagnosis was also evaluated. The data of 16,220 patients with RCC and 162,199 controls were extracted from the Renal Cell Cancer Database Sweden, with linkages across multiple national registers between 2005 and 2020. Cox proportional hazards regression, Kaplan-Meier curves and cumulative incidence were used for statistical analysis. The 5-year cumulative incidence of ESRD following RCC diagnosis was 2.4% (95% confidence interval [CI] 2.1-2.6) and 0.4% (95% CI 0.3-0.4) for the patients with RCC and controls, respectively. Age, chronic kidney disease, higher T-stage and radical nephrectomy (RN) were significant risk factors for ESRD within 1-year of surgery. A total of 104 and 12,152 patients with and without ESRD, respectively, survived 1-year postoperatively. The 5-year overall survival rates of patients with ESRD and those with RCC only were 50% (95% CI 0.40-0.60) and 80% (95% CI 0.80-0.81), respectively. Patients who developed ESRD following renal cancer surgery had significantly poorer survival outcomes. Advanced age, comorbidities, higher-stage tumours and RN were identified as risk factors for developing ESRD. Surgical decisions are crucial. Efforts to spare renal function, including nephron-sparing surgery and active surveillance in appropriate cases, are highly relevant to reduce the development of severe kidney dysfunction.

Native Kidney Renal Cell Carcinoma in Renal Allograft Transplant Patients - Our Experience.

The immunosuppression administered to renal transplant recipients to safeguard renal function elevates their susceptibility to renal cancer, which is estimated to be 15 times higher than in the general population. The current study aimed to analyze various aspects of native kidney renal cell carcinoma (RCC) in renal transplant recipients. This study involved a retrospective analysis of 11 patients who underwent nephrectomy for RCC in native kidneys among renal transplant recipients at our institution since 1992. Our institutional incidence was 0.4%. Median age at presentation was 57 (49-60) years. The ratio of male: female was 10:1. Most patients were asymptomatic at presentation and native kidney disease before transplantation was undetermined. In our study, the median time interval between diagnosis of RCC and transplant was 9.1 (8.4-11.2) years. All patients underwent native kidney nephrectomy. Clear cell type was more common than papillary type, 3.5 (2.5-4.2). Ten patients were diagnosed with stage I disease and one patient had stage IV disease. Fuhrman nuclear grading revealed low grades in nine patients and three patients had Grade 3. Immunosuppressive therapy modification was done in nine patients. Meticulous follow-up of renal transplant patients is essential for earlier diagnosis and appropriate treatment of native kidney RCC in transplant recipients. Authors recommend every year follow-up in transplant recipients with special emphasis on ultrasound of native kidney.

Case report: Uncommon gastric metastasis as a presentation of recurrent clear cell renal cell carcinoma

Renal cell carcinoma (RCC) is a kidney neoplasm that accounts for 85% of cases and has complex genetic pathways that affect its development and progression. RCC metastasis can occur in 20%-50% of patients and usually affects distant organs. Gastric metastases (GM) from RCC are rare and present as polyp-like growths in the submucosal layer, accounting for 0.2%-0.7% of cases. This case report describes an 84-year-old female with Furhman grade II ccRCC who presented with an atherothrombotic ischemic stroke and gastrointestinal bleeding nine years post-radical nephrectomy. Gastroscopy revealed a 12mm pseudopedicled gastric lesion with ulceration and bleeding, diagnosed as metastatic ccRCC. The discussion focuses on the rarity, diagnostic challenges, and prognostic elements of gastric metastasis from RCC. The median survival after detecting digestive metastasis varies widely, and the mechanisms include direct invasion and dissemination through lymphatic, transcelomic, or hematogenous routes. Prognostic markers encompass patient history, symptoms, time since RCC diagnosis, overall health, and genetic factors. Surgical removal of gastric lesions and targeted therapy are treatment options that can improve survival. This case report highlights the need for further research to enhance diagnostic and treatment strategies for this rare aspect of RCC pathophysiology.

Tetraspanin immunoassay for the detection of extracellular vesicles and renal cell carcinoma

AbstractHalf of patients with renal cell carcinoma (RCC) develop metastases. New and noninvasive biomarkers are needed for the diagnosis of RCC. The study aims to develop an EV‐based assay for the detection of RCC using a highly sensitive nanoparticle‐aided time‐resolved fluorescence immunoassay (NP‐TRFIA). To confirm the presence of tetraspanins on EVs, size exclusion chromatography is used to separate EV‐ and PE‐fractions from RCC4, 786‐O, and HEK293 cell lines. EV‐ and PE‐fractions are quantified using NP‐TRFIA assays established for CD9, CD63, CD81, and CD151. Tetraspanins are measured from RCC CCM and serum samples of RCC (n = 14), benign (n = 17), and healthy (n = 9) individuals. Among the tetraspanins, CD63 exhibits 3‐5‐fold higher expression on RCC4 and 786‐O CCM compared to HEK293. A sandwich CD63‐CD63 assay demonstrates significant discrimination of RCC patients from benign (p = 0.0003), and healthy (p = 0.005) individuals, respectively. Similarly, the CD81‐CD81 assay also enables significant separation of RCC patients compared to benign (p = 0.014), and healthy (p = 0.003) controls, respectively. This suggests that RCC cell lines and serum of RCC patients show higher amounts of CD63‐ and CD81‐EVs compared to controls. Detection of these EVs using NP‐TRFIA approach may play a vital role in the detection of RCC.

The role of preoperative immune cell metrics in renal cell carcinoma with a tumor thrombus.

The objective of this study was to stratify preoperative immune cell counts by cancer specific outcomes in patients with renal cell carcinoma (RCC) and a tumor thrombus after radical nephrectomy with tumor thrombectomy. Patients with a diagnosis of RCC with tumor thrombus that underwent radical nephrectomy with thrombectomy across an international consortium of seven institutions were included. Patients who were metastatic at diagnosis and those who received preoperative medical treatment were also included. Retrospective chart review was performed to collect demographic information, past medical history, preoperative lab work, surgical pathology, and follow up data. Neutrophil counts, lymphocyte counts, monocyte counts, neutrophil to lymphocyte ratios (NLR), lymphocyte to monocyte ratios (LMR), and neutrophil to monocyte ratios (NMR) were compared against cancer-specific outcomes using independent samples t-test, Pearson's bivariate correlation, and analysis of variance. One hundred forty-four patients were included in the study, including nine patients who were metastatic at the time of surgery. Absolute lymphocyte count preoperatively was greater in patients who died from RCC compared to those who did not (2 vs 1.4; p < 0.001). Patients with tumor pathology showing perirenal fat invasion had a greater neutrophil count compared to those who did not (7.5 vs 5.5; p = 0.010). Patients with metastatic RCC had a lower LMR compared to those without metastases after surgery (2.5 vs 3.2; p = 0.041). Tumor size, both preoperatively and on gross specimen, had an interaction with multiple immune cell metrics (p < 0.05). Preoperative immune metrics have clinical utility in predicting cancer-specific outcomes for patients with RCC and a tumor thrombus. Additional study is needed to determine the added value of preoperative serum immune cell data to established prognostic risk calculators for this patient population.

Influence of Dietary Polyunsaturated Fatty Acid Intake on Potential Lipid Metabolite Diagnostic Markers in Renal Cell Carcinoma: A Case-Control Study.

Non-invasive diagnostics are crucial for the timely detection of renal cell carcinoma (RCC), significantly improving survival rates. Despite advancements, specific lipid markers for RCC remain unidentified. We aimed to discover and validate potent plasma markers and their association with dietary fats. Using lipid metabolite quantification, machine-learning algorithms, and marker validation, we identified RCC diagnostic markers in studies involving 60 RCC and 167 healthy controls (HC), as well as 27 RCC and 74 HC, by analyzing their correlation with dietary fats. RCC was associated with altered metabolism in amino acids, glycerophospholipids, and glutathione. We validated seven markers (l-tryptophan, various lysophosphatidylcholines [LysoPCs], decanoylcarnitine, and l-glutamic acid), achieving a 96.9% AUC, effectively distinguishing RCC from HC. Decreased decanoylcarnitine, due to reduced carnitine palmitoyltransferase 1 (CPT1) activity, was identified as affecting RCC risk. High intake of polyunsaturated fatty acids (PUFAs) was negatively correlated with LysoPC (18:1) and LysoPC (18:2), influencing RCC risk. We validated seven potential markers for RCC diagnosis, highlighting the influence of high PUFA intake on LysoPC levels and its impact on RCC occurrence via CPT1 downregulation. These insights support the efficient and accurate diagnosis of RCC, thereby facilitating risk mitigation and improving patient outcomes.

The impact of the COVID-19 pandemic on renal cancer care

PurposeTo evaluate the impact of the COVID-19 pandemic on renal cell carcinoma (RCC) care in the Netherlands.MethodsNewly diagnosed RCCs between 2018 and 2021 were selected from the Netherlands Cancer Registry; 2020–2021 was defined as COVID period and 2018–2019 as reference period. Numbers of RCCs were evaluated using 3-week-moving averages, overall and by disease stage and age. Changes in treatment were evaluated with logistic regression analyses. To evaluate possible delays in care, time to start of treatment was assessed. The cumulative number of metastatic RCC (mRCC) over time was assessed to evaluate stage shift.ResultsDuring the 1st COVID wave (weeks 9–22, 2020), the number of new RCC diagnoses decreased with 15%. Numbers restored partially in 2020, but remained 10% lower compared to 2018/2019. The decline was mostly due to a drop in T1a/T1b RCCs and in age > 70 years. 2021 showed similar numbers of new RCC diagnoses compared to 2018/2019 without an increase due to previously missed RCCs. Treatment-related changes during the 1st COVID wave were limited and temporarily; less surgery in T1a RCCs in favor of more active surveillance, and in mRCC targeted therapy was preferred over immunotherapy. Time to start of firstline treatment was not prolonged during the 1st COVID wave. No increase in mRCC was found until the end of 2021.ConclusionsThe COVID-19 pandemic resulted in fewer RCC diagnoses, especially T1a/T1b tumors. Treatment-related changes appeared to be limited, temporarily and in accordance with the adapted guidelines. The diagnostic delay could lead to more advanced RCCs in later years but there are no indications for this yet.

Impact of Synchronous versus Metachronous Metastasis on Outcomes in Patients with Metastatic Renal Cell Carcinoma Treated with First-line Immune Checkpoint Inhibitor–based Combinations

Background and objectiveThe impact of time of metastasis onset with respect toprimary renal cell carcinoma (RCC) diagnosis on survival outcomes is not well characterized in the era of immune checkpoint inhibitor (ICI)-based combinations. Herein, we assessed differences in clinical outcomes between synchronous and metachronous metastatic RCC (mRCC). MethodsData for patients with mRCC treated with first-line ICI-based combination therapies between 2014 and 2023 were retrospectively collected. Patients were categorized as having synchronous metastasis if present within 3 mo of RCC diagnosis; metachronous metastasis was defined as metastasis >3 mo after primary diagnosis. Time to treatment failure (TTF), overall survival (OS), and the disease control rate (DCR) were assessed. Key findings and limitationsOur analysis included 223 eligible patients (126 synchronous and 97 metachronous). Median TTF did not significantly differ between the synchronous and metachronous groups (9 vs 19.8 mo; p = 0.063). Median OS was significantly shorter in the synchronous group (28.0 vs 50.9 mo; p = 0.001). Similarly, patients with synchronous metachronous metastasis (58.7% vs. 78.4%; p = 0.002). On multivariable analyses, synchronous metastasis remained independently associated with worse OS and DCR. Conclusions and clinical implicationsIn this hypothesis-generating study, patients with mRCC with synchronous metastasis who were treated with first-line ICI-based combinations have a poorer OS and worse DCR than those with metachronous mRCC. If these results are externally validated, time to metastasis could be included in prognostic models for mRCC. Patient summaryOur study demonstrates that patients treated with current first-line immunotherapies, who present with metastasis at the initial diagnosis of kidney cancer have worse overall survival compared to those who develop metastasis later. These results can help physicians and patients understand life expectancy.

Outcomes of thyroidectomy for secondary thyroid malignancies, a single center experience

BackgroundMetastasis of primary malignancies of other organs to the thyroid gland is a rare condition that may pose a diagnostic challenge. In this study, we aimed to report the clinicopathologic features and outcomes of patients treated for secondary thyroid malignancies in our center.Materials and methodsThe results of patients who underwent thyroidectomy in our clinic between 2015 and 2023 were evaluated retrospectively. Four patients who met the inclusion criteria were evaluated.ResultsThe primary tumor was renal cell carcinoma in 2 patients and squamous cell carcinoma of the lung in 2 patients. Median age was 64 years (min:59–max:69). The median nodule diameter was 2.85 cm. Extrathyroidal spread was present in 1 patient with renal cell carcinoma metastasis. The other patient with renal cell carcinoma metastasis had lymphatic invasion. Vascular invasion was detected in 1 patient with renal cell carcinoma metastasis and 1 patient with squamous cell carcinoma of the lung metastasis. Surgical margin positivity was present in 1 patient in each group. The median overall survival time was 27 (min:10–max:44) months in the renal cell carcinoma group and 11 (min:6–max:16) months in the squamous cell carcinoma group. After the diagnosis of primary renal cell carcinoma, one patient metastasized to thyroid tissue 43.00 and one patient 94.00 months later. In the squamous cell carcinoma group, one patient showed metastasis to thyroid tissue 6.00 months after the primary diagnosis, while the other patient was first diagnosed with metastatic tissue.ConclusionsMetastasis to the thyroid gland is a rare phenomenon with an incidence of 0.22% in all thyroid malignancies. It may occur before the detection of the primary tumor or during the follow-up of the primary malignancy. Although the overall prognosis is poor, it can be treated surgically.

Characterization of renal masses with MRI-based radiomics: assessment of inter-package and inter-observer reproducibility in a prospective pilot study.

To evaluate radiomics features' reproducibility using inter-package/inter-observer measurement analysis in renal masses (RMs) based on MRI and to employ machine learning (ML) models for RM characterization. 32 Patients (23M/9F; age 61.8 ± 10.6years) with RMs (25 renal cell carcinomas (RCC)/7 benign masses; mean size, 3.43 ± 1.73cm) undergoing resection were prospectively recruited. All patients underwent 1.5T MRI with T2-weighted (T2-WI), diffusion-weighted (DWI)/apparent diffusion coefficient (ADC), and pre-/post-contrast-enhanced T1-weighted imaging (T1-WI). RMs were manually segmented using volume of interest (VOI) on T2-WI, DWI/ADC, and T1-WI pre-/post-contrast imaging (1-min, 3-min post-injection) by two independent observers using two radiomics software packages for inter-package and inter-observer assessments of shape/histogram/texture features common to both packages (104 features; n = 26 patients). Intra-class correlation coefficients (ICCs) were calculated to assess inter-observer and inter-package reproducibility of radiomics measurements [good (ICC ≥ 0.8)/moderate (ICC = 0.5-0.8)/poor (ICC < 0.5)]. ML models were employed using reproducible features (between observers and packages, ICC > 0.8) to distinguish RCC from benign RM. Inter-package comparisons demonstrated that radiomics features from T1-WI-post-contrast had the highest proportion of good/moderate ICCs (54.8-58.6% for T1-WI-1min), while most features extracted from T2-WI, T1-WI-pre-contrast, and ADC exhibited poor ICCs. Inter-observer comparisons found that radiomics measurements from T1-WI pre/post-contrast and T2-WI had the greatest proportion of features with good/moderate ICCs (95.3-99.1% T1-WI-post-contrast 1-min), while ADC measurements yielded mostly poor ICCs. ML models generated an AUC of 0.71 [95% confidence interval = 0.67-0.75] for diagnosis of RCC vs. benign RM. Radiomics features extracted from T1-WI-post-contrast demonstrated greater inter-package and inter-observer reproducibility compared to ADC, with fair accuracy for distinguishing RCC from benign RM. Knowledge of reproducibility of MRI radiomics features obtained on renal masses will aid in future study design and may enhance the diagnostic utility of radiomics models for renal mass characterization.

A nomogram based on TFE3 IHC results and clinical factors as a preliminary screening scheme for TFE3-rearranged renal cell carcinoma.

TFE3 immunohistochemistry (TFE3-IHC) is controversial in the diagnosis of TFE3-rearranged renal cell carcinoma (TFE3-rearranged RCC). This study is to investigate the accuracy and sensitivity of IHC and establish a predictive model to diagnose TFE3-rearranged RCC. Retrospective analysis was performed by collecting IHC and fluorescence insitu hybridization (FISH) results from 228 patients. IHC results were evaluated using three scoring systems. Scoring system 1 is graded based on nuclear staining intensity, scoring system 2 is graded based on the percentage of stained tumor cell nuclei, and scoring system 3 is graded based on both the nuclear staining intensity and the percentage. We collected patients' IHC results and clinical information. Important variables were screened based on univariate logistic regression analysis. Then, independent risk factors were established through multivariate logistic regression, and a nomogram model was constructed. The model was validated in internal test set and external validation set. The receiver operating characteristic curve (ROC curve), calibration curve, and decision curve analysis (DCA) were generated to assess discriminative ability of the model. The accuracy of IHC based on three scoring systems were 0.829, 0.772, and 0.807, respectively. The model included four factors including age, gender, lymph node metastasis and IHC results. Area under the curve (AUC) values were 0.935 for the training set, 0.934 for the internal test set, 0.933 for all 228 patients, and 0.916 for the external validation set. TFE3 IHC has high accuracy in the diagnosis of TFE3-rearranged RCC. Clinical information such as age and lymph node metastasis are independent risk factors, which can be used as a supplement to the results of TFE3 IHC. This study confirms the value of IHC in the diagnosis of TFE3-rearranged RCC. The accuracy of the diagnosis can be improved by incorporating IHC with other clinical risk factors.

Case of spontaneous hematoma of the renal compartment resulting in hemorrhagic shock: A unique presentation in urology

Hemorrhagic shock from spontaneous retroperitoneal hematoma of renal origin is a rare condition, and there are few publications on this subject. We present the case of a 60-year-old obese patient who experienced hemorrhagic shock from a right renal subcapsular hematoma that had ruptured into the retroperitoneum after initiation of anticoagulant treatment for acute pulmonary edema in the context of recurrent paroxysmal atrial fibrillation. The CT scan revealed a retroperitoneal hematoma and a possible hemorrhagic cyst in the right kidney. An emergency nephrectomy was necessary for hemostasis. The histology of the nephrectomy specimen confirmed the diagnosis of renal cell carcinoma.

Rapid Examination of Nonprocessed Renal Cell Carcinoma Using Nonlinear Microscopy.

Histology, the traditional method of examining surgical tissue under a microscope, is a time-consuming process involving the fixation of tissue in formalin, dehydration, embedding in paraffin, and cutting into thin sections for hematoxylin-eosin (H&E) staining. Frozen section analysis is a faster alternative used in surgery to quickly evaluate tissue, but it has limitations, such as the size of the specimens that can be analyzed and difficulties with fatty and bony tissues. To rapidly examine nonprocessed kidney tumors using nonlinear microscopy (NLM), a fluorescence microscopy technique that can rapidly visualize fresh or fixed, rapidly stained, nonprocessed tissue resembling H&E histology. This technology eliminates the need for fixation, embedding, microtome sectioning, or slide preparation. In this study, a total of 190 tissue specimens were collected from 46 patients who underwent partial or radical nephrectomy. Two genitourinary pathologists confirmed that diagnostically important features present in the H&E images could also be identified in the NLM images. The results of this study demonstrated that NLM had a high degree of correspondence with H&E staining for the classical variants of renal cell carcinoma. NLM offers several clinical benefits, such as facilitating rapid renal cell carcinoma diagnosis, assessment of targeted kidney biopsies for both tumor and medical kidney diseases, and collection of fresh renal cell carcinoma tissue for molecular studies.

Fumarate Hydratase-Deficient Renal Cell Carcinoma With Predominant Tubulocystic Features Mimics Tubulocystic Renal Cell Carcinoma.

Fumarate hydratase (FH)-deficient renal cell carcinoma (RCC) rarely exhibits a predominant tubulocystic architecture with few other components. RCC with pure tubules and cysts lined by eosinophilic tumor cells with prominent nucleoli would raise the diagnosis of tubulocystic RCC. It is important to differentiate the 2 entities because they lead to different outcomes. To address the concern, a multicenter study was implemented to explore useful clinicopathologic features in differentiation between tubulocystic FH-deficient RCC and tubulocystic RCC. Clinical factors included age, sex, tumor size, and outcome. Morphologic factors included cell morphology, presence or absence of a nontubulocystic component, and stromal findings. Immunohistochemistry, fluorescence in situ hybridization, and next-generation sequencing were performed to explore the protein expression and molecular profiles of the 2 entities. We evaluated 6 patients with tubulocystic RCC and 10 patients with tubulocystic FH-deficient RCC. Tubulocystic RCC exhibited a small size (<4.0 cm, pT1a), low Ki-67 index (<5%), retained FH, and negative 2SC expression. Tubulocystic FH-deficient RCC had a relatively large size and a high Ki-67 index. Perinucleolar haloes, loss of FH, and 2SC positivity were always observed. Pure tubulocystic architecture was not observed in FH-deficient RCC, because focal nontubulocystic components can always be seen. We emphasized multiple sectioning to identify a nontubulocystic architecture to exclude tubulocystic RCC. Moreover, tumor size, FH/2SC staining, and the Ki-67 index can differentiate tubulocystic FH-deficient RCC from tubulocystic RCC. The diagnosis of tubulocystic RCC was not recommended in renal mass biopsy because of the limited tissues sampled.

Expression of programmed cell death ligand 1 and clinicopathological and immunological characteristics in fumarate hydratase-deficient renal cell carcinoma

Objective: To investigate the expression of programmed cell death ligand 1 (PD-L1), clinicopathologic features, immunohistochemical expression and molecular characteristics in fumarate hydratase (FH)-deficient renal cell carcinoma and to explore the potential application of immunotherapy in the patients. Methods: There were six patients with FH-deficient renal cell carcinoma treated at the First Affiliated Hospital of Fujian Medical University between January 2020 and October 2022. The clinical data, histological morphology, immunophenotype, PD-L1 expression and next-generation sequencing results were tabulated and analyzed. Results: There were 6 patients, all male, age ranged from 37 to 72 years (mean 45.7 years). Four cases were high-grade (WHO/ISUP grade3-4) with 2 or more histologic patterns, including papillary (most common), glandular, tubular, vesicular, ethmoid, nest-like, cystic and solid structures. Two cases were low-grade which showed nest-like, glandular, or tubular arrangement with eosinophilic flocculent cytoplasm and small intracellular vacuoles. Immunohistochemical analysis revealed strong expression of 2SC in all 6 cases, negative expression of FH in 5 cases, and positive expression of GATA3 in 5 cases. In high-grade cases, the mean values of CD4 and CD8 positive T-lymphocytes in advanced tumor invasion were 180.3/mm2 and 130.5/mm2, respectively. PD-L1 combined positive scores (CPS) were 20, 50, 5 and 30, respectively. The Ki-67 proliferative index were 20%, 20%, 10% and 30%, respectively. In low-grade cases, the mean values of CD4 and CD8 positive T-lymphocytes were 123.0/mm2 and 100.5/mm2, respectively. The PD-L1 CPS score was 1, and the Ki-67 proliferation index was 3%. High-throughput sequencing showed FH gene somatic mutation in 3 cases, FH gene germline mutation in 2 cases, and FH gene mutation was not detected in one case. Conclusion: FH-deficient renal cell carcinoma is more commonly high-grade than low grade. FH and 2SC are immunohistochemical markers used in the diagnosis of FH-deficient renal cell carcinoma, and GATA3 positivity is supportive of the diagnosis. The tumor infiltration of high-grade FH-deficient renal cell carcinoma shows an increase in CD4 and CD8 positive T-lymphocytes, and high expression of PD-L1; thus, anti-PD-L1 immunotherapy can be used as a treatment option.

Tuberous Sclerosis Complex (TSC) Identified by Genetic Testing After Histologic Diagnosis of Chromophobe Renal Cell Carcinoma

We report the case of a female patient with a histologic diagnosis of chromophobe renal cell carcinoma (ChRCC) after a left laparoscopic radical nephrectomy. Due to the unusual histologic diagnosis, a genetic test was ordered identifying tuberous sclerosis disease.

A pilot study of [68Ga]Ga-fibroblast activation protein inhibitor-04 PET/CT in renal cell carcinoma.

As a promising positron emission tomography (PET) tracer, [68Ga]Ga-fibroblast activation protein inhibitor-04([68Ga]Ga-FAPI-04) performs better than 2-[18F]fluoro-2-deoxy-d-glucose ([18F]FDG) at diagnosing primary and metastatic lesions in patients with various types of cancer. We investigated the utility of [68Ga]Ga-FAPI-04 PET/CT for the detection of primary and metastatic lesions in renal cell carcinoma (RCC). [18F]FDG PET/CT were used for comparison. Twenty-two patients with suspected RCC or recurrent RCC were enrolled in our study. Among these patients, 14 were newly diagnosed with RCC, 3 had recurrent RCC, and 5 were excluded from further analysis due to having benign renal tumours. Seventeen patients with RCC underwent [68Ga]Ga-FAPI-04 PET/CT, and 6 of them also received [18F]FDG PET/CT. The positive detection rates were calculated and compared with those in patients who underwent both scans. Data from 17 patients with RCC (median age: 60.5 years, interquartile range [IQR]: 54-70 years) were evaluated. The positive detection rate of [68Ga]Ga-FAPI-04 PET/CT for RCC was 64.7% (11/17). Lymph node metastases (n = 44), lung metastasis (n = 1), and bone metastasis (n = 1) were detected. Six patients with RCC underwent [68Ga]Ga-FAPI-04 and [18F]FDG PET/CT. [68Ga]Ga-FAPI-04 PET/CT showed a higher positive detection rate than [18F]FDG PET/CT in detecting RCC (83.3% [5/6] vs. 50% [3/6], P = 0.545). Additionally, [68Ga]Ga-FAPI-04 PET/CT has higher SUVmax (3.20 [IQR: 2.91-5.80 vs. 2.71 [IQR: 2.13-3.10], P = 0.116) and tumour-to-background ratio (TBR) values (1.60 [IQR: 1.33-3.67] vs. 0.86 [0.48-1.21], P = 0.028) than [18F]FDG PET/CT. These findings suggest that [68Ga]Ga-FAPI-04 PET/CT has potential value in RCC diagnosis. Further studies are warranted to validate these results. Clinical utility of [68Ga]Ga-FAPI-04 in RCC remains unclear, and there are not many similar studies in the literature. We evaluated the role of [68Ga]Ga-FAPI-04 in diagnosing RCC.

Texture analysis of CT- and MR-Images in the differential diagnosis of renal cell carcinoma: a review

INTRODUCTION: Renal cell carcinoma (RCC) is a heterogeneous group of diseases. The most common type of RCC is clear cell RCC. Tumor biopsy is the «gold» standard for verifying the diagnosis, however, it can be unsatisfactory due to the characteristic heterogeneity of the RCC structure. Non-invasive diagnostic methods — computed tomography and magnetic resonance imaging — in combination with the use of texture analysis can potentially provide a large amount of information about the structure of the kidney tumor and the presumed degree of its differentiation (grade).OBJECTIVE: Тo analyze publications devoted to texture analysis in RCC, the possibilities and prospects of using this method to increase the information content of CT and MR studies.MATERIALS AND METHODS: Our review presents data obtained from available sources PubMed, Scopus and Web of Science, published up to March 2022 inclusive, found using the keywords: renal cell carcinoma, CT, MRI, texture analysis, radiomics in Russian and English.RESULTS: The literature review describes the methods of texture analysis: selection of the region of interest, modality and contrast phase of the study, diagnostic aim. Based on the results of published scientific papers, the authors conclude that the use of texture analysis makes it possible to predict the grade of RCC with high sensitivity, specificity and accuracy, as well as to make a differential diagnosis of RCC with other kidney neoplasias, primarily lipid poor angiomyolipomas.CONCLUSION: The use of texture analysis based on published materials is extremely promising for non-invasive prediction of RCC grade and its differential diagnosis, however, the difference in methods and the lack of standardization of texture analysis requires additional research.

Computed tomography for visible haematuria - a single nephrographic phase is sufficient for detecting renal cell carcinoma.

No previous studies have compared two computed tomography (CT) protocols in patients presenting with visible haematuria, and most patients undergo a multiphase CT in order todetect upper tract malignancies. We aimed to prospectively compare the diagnostic performance ofsingle- and four-phase CT for detecting renal cell carcinoma (RCC) in patients with visible haematuria. 'A Prospective Trial for Examining Hematuria using Computed Tomography' (PROTEHCT) was a single-centre prospective paired diagnostic study in patients referred for CT due to painless visible haematuria between September 2019 and June 2021. All patients underwent four-phase CT (control) from which a single nephrographic phase dual energy CT (experimental) was extracted. Both were independently assessed for RCC by randomised radiologists. Histologically verified RCC defined a positive reference standard. Follow-up ascertainment of RCC diagnosis was completed in May 2022. Descriptive statistics were used to calculate the accuracies. Inter-reader agreement was assessed by kappa statistics. A total of 308 patients (median age, 68 years [interquartile range 53-77, range 18-96], 250 males) were included for analysis. RCC was diagnosed in seven (2.3%) patients during a median follow-up time of 19 months (interquartile range: 15-25). For the control and experimental CT, sensitivity was 100% versus 100%, specificity was 97% versus 98% and accuracy 97% versus 97%. The positive predictive value was 44% versus 50%, and the negative predictive value was 100% versus 100%. The agreement between the control and experimental CT was 98% (k = 0.79). A single nephrographic phase dual energy CT is sufficient for detecting RCC in patients with visible haematuria.

Gastrointestinal metastases in renal cell carcinoma: A retrospective multicenter GETUG (Groupe d′Étude des Tumeurs Uro-Génitales) study

BackgroundAmong patients with renal cell carcinoma (RCC), bone and visceral metastases have a poor prognosis, while endocrine gland metastases have a more favorable prognosis. Gastrointestinal metastases (GIMs) are rare, and their prognosis is still poorly understood. ObjectivesTo report clinical presentations, patient characteristics, therapeutic strategies, and prognosis of GIMs from RCC. MethodsWe retrospectively collected data from RCC patients presenting GIMs, in 10 French GETUG centers, between 2000 and 2021. ResultsWe identified 74 patients with 87 GIMs, mostly gastric or duodenal. The median age at GIM diagnosis was 69 years and 76% of patients already had other metastases. GIMs occurred after a median duration of 5.4 years (IC95%=[4.2–7.1]) and 1.9 years (IC95%=[1.2–3.8]) from RCC diagnosis and first metastasis, respectively. GIMs were symptomatic in 52 patients (70%), with anemia in 41 patients (55%) and/or gastrointestinal bleeding in 31 patients (42%). Only 22 asymptomatic patients (30%) were fortuitously diagnosed. GIM management consisted of systemic treatment only in 29 GIMs (33%), local treatment only in 23 GIMs (26%), and both local and systemic treatment in 18 GIMs (21%). For 17 GIMs (20%), there was no therapeutic modification. After diagnosis of GIM, median overall survival was 19 months. ConclusionWe report the largest retrospective cohort of GIMs in RCC patients. They should be suspected in case of anemia or gastrointestinal bleeding in any patient with a history of RCC. Their management varies widely depending on their location in the digestive tract and whether or not they are symptomatic.