Histomorphometric and Immunohistochemical Diagnosis of Renal Cell Carcinoma: Review Article.

Renal cell carcinoma (RCC) is derived from renal tubular epithelial cells and is among the 10 most common cancers worldwide. Incidence of renal cell carcinoma is 400,000 individuals worldwide per year. The age of diagnosis is approximately 60years, and twice as many men are diagnosed as women. African Americans have a slightly higher rate of RCC than do White peoples. The reasons for this are not clear. Inherited syndromes in family, long term dialysis, smoking individuals who had quit smoking >10 years prior had a lower risk when compared to those who had quit <10 years. 22.5 pack-year smokers had a more than 50.0% increased RCC risk compared to nonsmokers, high body mass index i.e. 5kg/m2 increase in body mass index (BMI) was found to be strongly associated with RCC. BMI >35kg/m2 is associated with higher incidence of Cancer raise blood pressure- Higher BMI and hypertension were independently shown to increase the long-term risk of RCC in men. A rise of blood pressure of 10mmHg is associated with 10-22 percent risk of RCC. Clear cell carcinoma is the most common variety of renal cell carcinoma as compared to other varieties of renal cell carcinomas (68.0-75.0%). It has also been found that CAIX is positive for all papillary renal cell carcinoma and negative for CK7, AMACR & TEF. We also found that CK7, EMA, CD117 and CAIX are most commonly positive for all chromophobe renal cell carcinoma. It has been found that clear cell carcinoma is the most common variety of renal cell carcinoma as compared to other varieties of renal cell carcinomas (68.0-75.0%). Again it has also been found that CAIX is positive for all papillary renal cell carcinoma and negative for CK7, AMACR and TEF. Here it has been found that chromophobe carcinoma is most commonly positive for CK7, EMA, CD117 and CAIX. In a patient coming with signs and symptoms of renal cell carcinoma can be confirmed with the help of histoimmunological markers and in that case one can plan for a proper planning of management.

Unlocking Precision Medicine: Liquid Biopsy Advancements in Renal Cancer Detection and Monitoring.

Renal cell carcinoma (RCC) remains a formidable diagnostic challenge, especially in the context of small renal masses. The quest for non-invasive screening tools and biomarkers has steered research towards liquid biopsy, focusing on microRNAs (miRNAs), exosomes, and circulating tumor cells (CTCs). MiRNAs, small non-coding RNAs, exhibit notable dysregulation in RCC, offering promising avenues for diagnosis and prognosis. Studies underscore their potential across various biofluids, including plasma, serum, and urine, for RCC detection and subtype characterization. Encouraging miRNA signatures show correlations with overall survival, indicative of their future relevance in RCC management. Exosomes, with their diverse molecular cargo, including miRNAs, emerge as enticing biomarkers, while CTCs, emanating from primary tumors into the bloodstream, provide valuable insights into cancer progression. Despite these advancements, clinical translation necessitates further validation and standardization, encompassing larger-scale studies and robust evidence generation. Currently lacking approved diagnostic assays for renal cancer, the potential future applications of liquid biopsy in follow-up care, treatment selection, and outcome prediction in RCC patients are profound. This review aims to discuss and highlight recent advancements in liquid biopsy for RCC, exploring their strengths and weaknesses in the comprehensive management of this disease.

Label-Free SERS of Urine Components: A Powerful Tool for Discriminating Renal Cell Carcinoma through Multivariate Analysis and Machine Learning Techniques.

The advent of Surface-Enhanced Raman Scattering (SERS) has enabled the exploration and detection of small molecules, particularly in biological fluids such as serum, blood plasma, urine, saliva, and tears. SERS has been proposed as a simple diagnostic technique for various diseases, including cancer. Renal cell carcinoma (RCC) ranks as the sixth most commonly diagnosed cancer in men and is often asymptomatic, with detection occurring incidentally. The onset of symptoms typically aligns with advanced disease, aggressive histology, and unfavorable prognosis, and therefore new methods for an early diagnosis are needed. In this study, we investigated the utility of label-free SERS in urine, coupled with two multivariate analysis approaches: Principal Component Analysis combined with Linear Discriminant Analysis (PCA-LDA) and Support Vector Machine (SVM), to discriminate between 50 RCC patients and 44 healthy donors. Employing LDA-PCA, we achieved a discrimination accuracy of 100% using 13 principal components, and an 88% accuracy in discriminating between different RCC stages. The SVM approach yielded a training accuracy of 100%, a validation accuracy of 99% for discriminating between RCC and controls, and an 80% accuracy for discriminating between stages. The comparative analysis of raw and normalized SERS spectral data shows that while raw data disclose relative concentration variations in urine metabolites between the two classes, the normalization of spectral data significantly improves the accuracy of discrimination. Moreover, the selection of principal components with markedly distinct scores between the two classes serves to alleviate overfitting risks and reduces the number of components employed for discrimination. We obtained the accuracy of the discrimination between the RCC patients cases and healthy donors of 90% for three PCs and a linear discrimination function, and a 88% accuracy of discrimination between stages using six PCs, mitigating practically the risk of overfitting and increasing the robustness of our analysis. Our findings underscore the potential of label-free SERS of urine in conjunction with chemometrics for non-invasive and early RCC detection.

Wide-Targeted Semi-Quantitative Analysis of Acidic Glycosphingolipids in Cell Lines and Urine to Develop Potential Screening Biomarkers for Renal Cell Carcinoma.

Glycosphingolipids (GSLs), mainly located in the cell membrane, play various roles in cancer cell function. GSLs have potential as renal cell carcinoma (RCC) biomarkers; however, their analysis in body fluids is challenging because of the complexity of numerous glycans and ceramides. Therefore, we applied wide-targeted lipidomics using liquid chromatography-tandem mass spectrometry (LC-MS/MS) with selected reaction monitoring (SRM) based on theoretical mass to perform a comprehensive measurement of GSLs and evaluate their potency as urinary biomarkers. In semi-quantitative lipidomics, 240 SRM transitions were set based on the reported/speculated structures. We verified the feasibility of measuring GSLs in cells and medium and found that disialosyl globopentaosylceramide (DSGb5 (d18:1/16:0)) increased GSL in the ACHN medium. LC-MS/MS analysis of urine samples from clear cell RCC (ccRCC) patients and healthy controls showed a significant increase in the peak intensity of urinary DSGb5 (d18:1/16:0) in the ccRCC group compared with that in the control group. Receiver operating characteristic analysis indicated that urinary DSGb5 could serve as a sensitive and specific marker for RCC screening, with an AUC of 0.89. This study demonstrated the possibility of urinary screening using DSGb5 (d18:1/16:0). In conclusion, urinary DSGb5 (d18:1/16:0) was a potential biomarker for cancer screening, which could contribute to the treatment of RCC patients.

[Modern view on the problem of diagnostics of renal angiomioadenomatous tumor].

INTRODUCTION: Angiomyoadenomatous tumor as a nosological entity is not included in the latest version of the International Histological Classification of Kidney Tumors (WHO, 2022) and is related to provisional entity. Currently, there is no consensus among researchers about the nosological affiliation of an angiomyoadenomatous tumor. AIM: To comparatively analyze the histological, immunophenotypic, ultrastructural and molecular parameters of renal angiomyoadenomatous tumor and clear cell papillary renal cell tumor. MATERIALS AND METHODS: The study was performed on surgical specimen from 5 and 10 patients with renal angiomyoadenomatous tumor and with clear cell papillary renal cell tumor, respectively. Immunohistochemical study was carried out on paraffin sections according to the standard protocol. Antibodies HMWCK, AE1/AE3, 7, E-Cadherin, EMA, PAX8 and 9 were chosen. To study tumor tissues on semi-thin and ultra-thin sections, an electron microscope Philips TECNAI 12 BioTwinD-265 was used. For in situ fluorescent diagnostic detection, defined centromere probes, LSI 13/21, LSI N25 /LSI ARSA, TelVysion telomeric probe and a two-color VHL/CEP3 probe were used. RESULTS: Angiomyoadenomatous tumor is characterized by a three-phase structure. In contrast to clear cell papillary renal cell tumor, angiomyoadenomatous tumors show complete membranous expression of CA9. CONCLUSION: Our results allow to state that angiomyoadenomatous tumor and clear cell papillary renal cell tumor are different neoplasms.

Stauffer syndrome : a rare paraneoplastic complication of renal cell carcinoma to be kept in mind. Case report and literature survey.

The authors report the case of a 74-years-old woman treated by immunotherapy for a metastatic renal cell carcinoma and having developed an important cholestasis with thrombocytosis, increased CRP, leucocytosis and hypoalbuminemia. Liver remained free of metastases at medical imaging. The diagnosis of a Stauffer syndrome was confirmed by the hepatic biopsy. A complete response of liver disorders was obtained after nephrectomy. From literature survey, Stauffer syndrome should be kept in mind in cancer patients, especially those suffering from a renal cell carcinoma, presenting with cholestasis with no underlying cause.

Endolymphatic sac tumor misdiagnosed as metastatic renal cell carcinoma: Pitfalls in morphology and immunohistochemistry.

Endolymphatic sac tumor (ELST) is a rare disease that originates from the endolymphatic sac system of the inner ear. Being a low-grade malignant tumor, ELST has a mild morphology and is characterized by a slow but aggressive growth. Most clinicians and pathologists are unfamiliar with this disease. ELST can be misdiagnosed as metastatic renal cancer because of the similarity in morphology and expression of nephrogenic markers such as PAX8. The presented case of a 27-year-old man revealed that observing the characteristic location and confirming the absence of renal neoplasm to rule out the possibility of metastasis are critical for obtaining an accurate final diagnosis.

Humoral complementomics - exploration of noninvasive complement biomarkers as predictors of renal cancer progression.

Despite the progress of anti-cancer treatment, the prognosis of many patients with solid tumors is still dismal. Reliable noninvasive biomarkers are needed to predict patient survival and therapy response. Here, we propose a Humoral Complementomics approach: a work-up of assays to comprehensively evaluate complement proteins, activation fragments, and autoantibodies targeting complement proteins in plasma, which we correlated with the intratumoral complement activation, and/or local production, focusing on localized and metastatic clear cell renal cell carcinoma (ccRCC). In two prospective ccRCC cohorts, plasma C2, C5, Factor D and properdin were elevated compared to healthy controls, reflecting an inflammatory phenotype that correlated with plasma calprotectin levels but did not associate with CRP or with patient prognosis. Conversely, autoantibodies against the complement C3 and the reduced form of FH (a tumor neo-epitope reported in lung cancer) correlated with a favorable outcome. Our findings pointed to a specific group of patients with elevated plasma C4d and C1s-C1INH complexes, indicating the initiation of the classical pathway, along with elevated Ba and Bb, indicating alternative pathway activation. Boostrapped Lasso regularized Cox regression revealed that the most predictive complement biomarkers were elevated plasma C4d and Bb levels at the time of surgery, which correlated with poor prognosis. In conclusion, we propose Humoral Complementomics as an unbiased approach to study the global state of the complement system in any pathological plasma sample and disease context. Its implementation for ccRCC revealed that elevated C4d and Bb in plasma are promising prognostic biomarkers, correlating with shorter progression-free survival.

Unveiling the challenges of UTUC biopsies and cytology: insights from a global real-world practice study.

PURPOSE: Diagnostic ureteroscopy (dURS) is optional in the assessment of patients with upper tract urothelial carcinoma (UTUC) and provides the possibility of obtaining histology. METHODS: To evaluate endoscopic biopsy techniques and outcomes, we assessed data from patients from the CROES-UTUC registry. The registry includes multicenter prospective collected data on diagnosis and management of patients suspected having UTUC. RESULTS: We assessed 2380 patients from 101 centers. dURS with biopsy was performed in 31.6% of patients. The quality of samples was sufficient for diagnosis in 83.5% of cases. There was no significant association between biopsy techniques and quality (p = 0.458). High-grade biopsy accurately predicted high-grade disease in 95.7% and high-risk stage disease in 86%. In ureteroscopic low-grade tumours, the prediction of subsequent low-grade disease was 66.9% and low-risk stage Ta-disease 35.8%. Ureteroscopic staging correctly predicted non-invasive Ta-disease and ≥ T1 disease in 48.9% and 47.9% of patients, respectively. Cytology outcomes did not provide additional value in predicting tumour grade. CONCLUSION: Biopsy results adequately predict high-grade and high-risk disease, but approximately one-third of patients are under-staged. Two-thirds of patients with low-grade URS-biopsy have high-risk stage disease, highlighting the need for improved diagnostics to better assess patient risk and guide treatment decisions. CLINICAL TRIAL REGISTRATION: The study was registered at ClinicalTrials.gov (ClinicalTrials.gov NCT02281188; https://clinicaltrials.gov/ct2/show/NCT02281188 ).

A 42-year-old patient with renal cell carcinoma presenting as low back pain: A case report.

RATIONALE: Renal cell carcinoma (RCC) is the most common renal neoplasm, accounting for 2.4% of all cancers in Korea. Although the usual clinical manifestations of RCC include flank pain, hematuria, and palpable mass, RCC is generally characterized by a lack of early warning signs and is mostly discovered incidentally in advanced stage. This case report describes a 42-year-old Korean man diagnosed with giant RCC who presented with simple back pain. PATIENT CONCERNS: The clinical manifestation of a 42-year-old Korean man was chronic back pain. DIAGNOSES: Contrast-enhanced computed tomography showed a 19.1-cm sized heterogeneous enhancing mass on the right kidney and tumor thrombosis extending into inferior vena cava. INTERVENTION: Due to the large size of the tumor and extensive tumor thrombosis, the multidisciplinary team decided to administer neoadjuvant chemotherapy and an anticoagulant. Following 12 cycles of treatment with nivolumab and cabozantinib, he underwent a right radical nephrectomy with an adrenalectomy and tumor thrombectomy. OUTCOMES: Treatment was successful and posttreatment he started a cancer rehabilitation program. He was followed-up as an outpatient and no longer complains of back pain. LESSONS: RCC can manifest clinically as back pain, with diagnosis being difficult without appropriate imaging modalities. RCC should be included in the differential diagnosis of patients with low back pain, even at a young age.

Heterotopic bone formation in a case of clear cell renal cell carcinoma: A case report.

Renal cell carcinoma (RCC) with heterotopic formation has been reported very rarely. We report this rare entity in a 33-year-old female patient who came to the out-patient department after complaining of pain in the lumbar region of the left side for 2 years. A computed tomography scan showed a heterogeneously enhancing lesion originating from the posterior cortex of the left kidney in the upper pole. It had many chunky calcification foci and was treated with left robotic partial nephrectomy. Histo-pathological examination revealed clear cell RCC with the heterotopic bone formation with a tumor size measuring 5 × 4 × 2.5 cm; the tumor was limited to the kidney, and the tumor resection margin were free of tumor, WHO/ISUP Grade 2. The pathological stage (AJCC 8th edition PTNM) was p T1b p NX p MX. The prognostic implications regarding calcification are poorly addressed in the literature. Patients suffering from osseous metaplasia are often in their early stages of the disease and have a favorable prognosis.

Investigating the Impact of Tumor Biology and Social Determinants on Time to Diagnosis and Stage at Presentation of Wilms Tumor.

Delays in diagnosis and time to diagnosis generally are used interchangeably in cancer disparity research, but these terms may have important differences. Although these terms are related, we hypothesize that time to diagnosis is determined by the aggressiveness of the tumor based on intrinsic factors such as tumor biology, whereas delays in diagnosis are caused by extrinsic factors such as socioeconomic status, leading to presentation at higher stage of disease due to barriers of care. We conducted a retrospective study of 306 patients diagnosed with Wilms tumor at Children's Hospital Colorado between 1971 and 2016 identifying patient barriers as extrinsic markers and using unfavorable histology and loss of heterozygosity as markers of aggressive tumor biology. Multivariable logistic regression was performed. Patients with Medicaid were more likely to present greater than 4 days after initial symptoms compared to those with private insurance, and those with housing concerns were more likely to be diagnosed greater than 9 days from initial symptoms. Tumor biology was noted to be associated with higher stage at diagnosis, but patient barriers were not. These findings suggest the interplay between tumor biology, patient barriers, diagnostic timing, and stage at diagnosis is more complex, multifactorial, and in need of further study.

Urine cytology in the detection of renal cell carcinomas - a territory-wide multi-institutional retrospective review of more than 2 decades.

INTRODUCTION: Compared with urothelial lesions of the upper urinary tract, the diagnostic performance of urine cytology in detection of renal cell carcinomas is underreported. This study aims to establish the role of urine cytology in the assessment of renal carcinomas by a multi-institute review of urine cytology from nephrectomy confirmed renal cell carcinomas, referenced against renal urothelial and squamous cell carcinomas. METHODS: Records of nephrectomy performed from the 1990s to 2020s at three hospitals were retrieved and matched to urine cytology specimens collected within 1 year prior. Patient demographics, specimen descriptors, and histology and staging parameters were reviewed and compared against cytologic diagnoses. RESULTS: There were 1147 cases of urine cytology matched with renal cell carcinomas, with 666 renal urothelial/squamous carcinomas for comparison. The detection rate for urothelial/squamous (atypia or above [C3+]: 63.1%; suspicious or above [C4+]: 24.0%) were higher than renal cell carcinoma (C3+: 13.1%; C4+: 1.5%) (p < 0.001). The positive rate for upper tract urine exceeded other collection methods at 45.0% (C3+) and 10.0% (C4+) (p < .01). Other factors associated with increased positive rates were male sex, collecting duct carcinoma histology, nuclear grade, and renal/sinus involvement (p < .05). Multivariate analysis revealed additional positive correlations with presence of sarcomatoid tumor cells, lymphovascular invasion, and perinephric fat involvement (p < .05). Larger lesion size and higher urine volume did not improve detection rates (p < .05). CONCLUSIONS: The detection rate of renal cell carcinomas is suboptimal compared with urothelial carcinomas, although urine samples collected from cystoscopy or percutaneous nephrostomy significantly outperformed voided urine specimens.

The clinicopathologic and molecular features, and treatment outcome of fumarate hydratase-deficient renal cell carcinoma: a retrospective comparison with type 2 papillary renal cell carcinoma.

BACKGROUND: To compare clinicopathologic, molecular features, and treatment outcome between fumarate hydratase-deficient renal cell carcinoma (FH-dRCC) and type 2 papillary renal cell carcinoma (T2 pRCC). METHODS: Data of T2 pRCC patients and FH-dRCC patients with additional next-generation sequencing information were retrospectively analyzed. The cancer-specific survival (CSS) and disease-free survival (DFS) were primary endpoint. RESULTS: A combination of FH and 2-succino-cysteine (2-SC) increased the rate of negative predictive value of FH-dRCC. Compared with T2 pRCC cases, FH-dRCC cases displayed a greater prevalence in young patients, a higher frequency of radical nephrectomy. Seven FH-dRCC and two T2 pRCC cases received systemic therapy. The VEGF treatment was prescribed most frequently, with an objective response rate (ORR) of 22.2% and a disease control rate (DCR) of 30%. A combined therapy with VEGF and checkpoint inhibitor reported an ORR of 40% and a DCR of 100%. FH-dRCC cases showed a shortened CSS (P = 0.042) and DFS (P < 0.001). The genomic sequencing revealed 9 novel mutations. CONCLUSIONS: Coupled with genetic detection, immunohistochemical biomarkers (FH and 2-SC) can distinguish the aggressive FH-dRCC from T2 pRCC. Future research is awaited to illuminate the association between the novel mutations and the clinical phenotypes of FH-dRCC in the disease progression.

Synchronous hepatocellular carcinoma and renal cell carcinoma: A cytological marvel.

Multiple primary synchronous tumours have always created an inquisitiveness among clinicians, radiologists and pathologists. The diagnosis invariably proposes a challenge to diagnosticians. The coexistence of a primary hepatocellular carcinoma (HCC) and renal cell carcinoma (RCC) is exceedingly rare, with countable number of cases being reported in literature. We report a pioneer case of 75-year-old male, having chronic hepatitis B, diagnosed with synchronous primary RCC and HCC in by fine-needle aspiration cytology (FNAC) and confirmed by immunohistochemistry.

Sarcomatoid variant of Xp11 translocation renal cell carcinoma: A rare case report in an adult female.

Xp11 translocation renal cell carcinoma (XPTRCC) is a very rare kidney neoplasm, which has been predominantly reported in young patients. Sarcomatoid transformation in renal cell carcinomas is known. However, its occurrence in XPTRCC is unreported so far in the literature. We report a unique case of sarcomatoid transformation in a XPTRCC in a 23-year-old female, who presented with a huge right-sided renal mass and had metastatic deposits in lungs. Morphologically, clear cell morphology with papillary architecture along with foci of sarcomatoid transformation and rhabdoid differentiation were noted. Immunohistochemistry showed Pax-8 and TFE-3 expression in all components including the sarcomatous areas, whereas CK and EMA were expressed in conventional clear cell component. We present an extremely rare case of sarcomatous transformation in XPTRCC and discuss the case as determined by histopathology and immunocytochemistry. To our knowledge, this is the first case of sarcomatoid transformation XPTRCC being reported in the world literature.

Vascular, adipose tissue, and/or calyceal invasion in clear cell tubulopapillary renal cell tumour: potentially problematic diagnostic scenarios.

AIMS: The 2022 WHO classification for kidney tumours recently downgraded clear cell tubulopapillary (also known as clear cell papillary) renal cell carcinoma (RCC) to a benign neoplasm (i.e. clear cell tubulopapillary renal cell tumour) based on the overwhelmingly banal nature of this neoplasm. However, it has been recognized that some clear cell tubulopapillary renal cell tumours demonstrate vascular, adipose or pelvicalyceal invasion, raising the possibility of more aggressive behaviour. The goal of this study was to determine if these 'high stage' features have an effect on tumour prognosis, warranting a carcinoma designation. METHODS AND RESULTS: After excluding cases with tissue artefact (i.e. prior core biopsy track changes) and other RCC subtypes with next-generation sequencing, nine clear cell tubulopapillary renal cell tumours with these so-called 'high stage' features, and otherwise classic morphologic and immunophenotypic findings, including low-grade cytology and 'cup-like' CA9 expression, were evaluated. Median tumour size was 2.2 cm with a range of 0.8 to 6.7 cm. Eight cases (89%) demonstrated perinephric or hilar adipose tissue invasion, although most of these cases showed a bulging (in contrast to an infiltrative) growth pattern. One case demonstrated renal vascular invasion in addition to hilar adipose tissue invasion, and one case demonstrated extension into the pelvicalyceal system. There were no recurrences or evidence of metastatic disease. CONCLUSION: These overall findings continue to support the benign designation for clear cell tubulopapillary renal cell tumours, despite morphologic features that might raise the possibility of a 'higher stage' neoplasm.

NCCN Guidelines® Insights: Kidney Cancer, Version 2.2024.

The NCCN Guidelines for Kidney Cancer provide multidisciplinary recommendations for diagnostic workup, staging, and treatment of patients with renal cell carcinoma (RCC). These NCCN Guidelines Insights focus on the systemic therapy options for patients with advanced RCC and summarize the new clinical data evaluated by the NCCN panel for the recommended therapies in Version 2.2024 of the NCCN Guidelines for Kidney Cancer.

Diagnostic, prognostic, and therapeutic potential of exosomal microRNAs in renal cancer.

Renal cell carcinoma (RCC) arises from the tubular epithelial cells of the nephron. It has the highest mortality rate among urological cancers. There are no effective therapeutic approaches and no non-invasive biomarkers for diagnosis and follow-up. Thus, suitable novel biomarkers and therapeutic targets are essential for improving RCC diagnosis/prognosis and treatment. Circulating exosomes such as exosomal microRNAs (Exo-miRs) provide non-invasive prognostic/diagnostic biomarkers and valuable therapeutic targets, as they can be easily isolated and quantified and show high sensitivity and specificity. Exosomes secreted by an RCC can exhibit alterations in the miRs' profile that may reflect the cellular origin and (patho)physiological state, as a ''signature'' or ''fingerprint'' of the donor cell. It has been shown that the transportation of renal-specific miRs in exosomes can be rapidly detected and measured, holding great potential as biomarkers in RCC. The present review highlights the studies reporting tumor microenvironment-derived Exo-miRs with therapeutic potential as well as circulating Exo-miRs as potential diagnostic/prognostic biomarkers in patients with RCC.

[A rare malignant tumor of the renal vein]. / Une tumeur maligne rare de la veine rénale.

The renal vein is an exceptional location for leiomyosarcoma, an aggressive malignant tumor of smooth-muscle origin with a poor prognosis. We report the case of a 55-year-old female patient who consulted for left flank pain that had been present for 6 months. A CT scan revealed a 9.4cm left retroperitoneal mass in contact with the psoas muscle, left kidney, stomach, spleen, left colon and extending up to the pancreas, raising the suspicion of a tumour originating in the retroperitoneal tissues. A biopsy revealed a smooth-muscle cell tumour with a degree of malignancy difficult to define. The patient underwent a monobloc left compartmentectomy, which led to the diagnosis of leiomyosarcoma of the left renal vein. A review of the literature on these rare tumours in this location is presented.