Angiomyolipoma of the kidney: clinicopathological and immunohistochemical study

Clinical evolution of bladder carcinosarcoma: A case report and literature review

RATIONALE

Bladder carcinosarcoma (BC) is a malignant tumor composed of a mixture of malignant epithelial and stromal components. Carcinosarcoma mostly occurs in the upper respiratory tract and upper gastrointestinal tract and is less common in the urinary system. The incidence of malignant tumors of the urinary system is <3%. It rarely occurs in the bladder and accounts for approximately 0.31% of all malignant bladder tumors. A literature review and this report will help to further improve our understanding, diagnosis, and treatment of bladder carcinosarcoma (BC).

PATIENT CONCERN

We describe the case of an 80-year-old female patient who was admitted to the hospital with a history of intermittent hematuria for 3 years. Furthermore, total cystectomy was refused when a BC was diagnosed. Palliative resection surgery was necessary because of the recurrent hematuria and abdominal pain.

DIAGNOSES

Pathologically confirmed BC after surgery.

INTERVENTIONS

The patient's first transurethral resection of bladder tumor (TURBT) was diagnosed as BC. However, the patient refused a total cystectomy. Two months after intravesical treatment with epirubicin, bladder tumor recurrence was observed during follow-up cystoscopy. The patient underwent a second TURBT for hemostatic treatment due to persistent hematuria. Due to hematuria and abdominal pain, a third TURBT was performed to reduce tumor size and stop bleeding. Finally, tumor recurrence resulted in bilateral hydronephrosis, and the patient underwent bilateral renal catheter drainage guided by B-ultrasound.

OUTCOMES

Bladder carcinosarcoma caused uremia, electrolyte imbalance, and sepsis. Approximately 19 months after the discovery of the tumor, the patient died.

LESSONS

Radical bladder resection is recommended once a BC is diagnosed. By reporting the cases and reviewing the literature in the database, we will summarize the epidemiology, origin, etiology, clinical features, existing treatments, and prognostic factors of BC, and propose new prospects for BC therapy.

Qualitative and quantitative characteristics of CEUS for renal cell carcinoma and angiomyolipoma: a narrative review

Incidental findings of renal masses are increasing. However, a substantial portion of surgically treated renal masses turn out to be benign on histopathological examination. Thus, there is a clear need for improved pre-surgical assessment to minimize unnecessary invasive procedures. The challenge intensifies when distinguishing between renal cell carcinoma (RCC) and angiomyolipoma (AML) in renal lesions smaller than 4 cm with minimal adipose tissue. In such cases, contrast-enhanced ultrasound (CEUS) has emerged as a valuable diagnostic tool, by utilizing both qualitative and quantitative parameters. Quantitative measures offer objectivity, reliability, and reproducibility compared to qualitative parameters, enabling the characterization of RCC subtypes and differentiation from AML. Qualitative features as enhancement pattern, degree, and peak were less helpful in distinguishing triphasic minimal fat AML (TAML) from epithelioid AML (EAML), with the pseudocapsule sign potentially being the only distinguishing qualitative feature. The pseudocapsule sign was more frequently observed in ccRCCs (38.0%) than in AMLs (15.6%). Moreover, it was detected in 40.0% of EAMLs and 34.5% of ccRCCs but not in TAMLs due to similar growth patterns between EAMLs and low-grade ccRCCs. Quantitative measures such as the time-to-peak (TTP) ratio can further enhance diagnostic accuracy and also TOC ratio should be considered, as it was higher in clear cell RCCs (ccRCCs) and in EAMLs compared to TAMLs, indicating behavior similar to ccRCCs. However, CEUS remains an operator-dependent exam.

Epitheloid Angiomyolipomas of the Kidney: Rare Renal Tumors Associated With Poor Prognoses

OBJECTIVE

To demonstrate the clinical spectrum and challenges associated with clinical management of epitheloid angiomyolipomas (eAML).

METHODS

We retrospectively reviewed the surgical database of a high-volume tertiary kidney cancer center from 2015 to 2020 to identify cases with a final histological diagnosis of eAML. Descriptive analysis of all cases was conducted.

RESULTS

Five surgical cases of eAMLs were identified. Two of which have had no tumor recurrence since surgery, and three patients passed away due to disease progression.

CONCLUSION

eAML are rare renal tumors which the World Health Organisation (5th Edition, 2022) and International Classification of Diseases for Oncology classify as having unspecified, borderline, or uncertain behavior. Here, we report that can also demonstrate aggressive behavior with fatal consequences. Post-operative follow-up should be recommended for all, with shorter intervals for patients with poor prognostic factors.

Advancements in the diagnosis and treatment of renal epithelioid angiomyolipoma: A narrative review

Renal epithelioid angiomyolipoma (EAML) is a unique subtype of angiomyolipoma that contains a variety of cytoplasmic-rich, eosinophilic cytoplasm epithelioid cells in addition to mature adipocytes, hyaline thick-walled vessels, and smooth muscle-like spindle cells. In recent years, increasing evidence has shown that EAML is a potentially malignant tumor. Due to the lack of typical clinical manifestations and imaging features, it is difficult to diagnose before surgery, and the diagnosis mainly depends on postoperative histopathological examination. With the advancement of pathological diagnostic techniques, more EAML cases has been discovered, but clinicians still lack a comprehensive understanding of EAML. This review comprehensively describes some pathological and clinical features of EAML, with special attention to the pathogenesis and treatment of malignant EAML in order to assist with clinical diagnosis and treatment.

A rare primary posterior mediastinal angiolipoma: A case report

Mediastinal angiolipoma is a rare benign neoplasm composed of mature adipose tissue with an abnormal vessel. Owing to its unspecific symptoms and slow progressions, the diagnosis of this disease is often delayed by clinicians. Here we present a 68-years-old-woman presented with mild chest pain radiates to the back with chronic dry cough. Chest imaging showed right medial posterior intrathoracic mass attached to 3rd-5th vertebrae body without bone destructions. Exploratory thoracotomy with segmentectomy was successfully performed. Histopathology examinations showed adipose tissue surrounded by a blood vessel nest, typical for angiolipoma. The patient showed rapid recovery and was discharged a week after the surgery. After two years of follow-up, the patient showed no sign of tumor recurrence and was clinically stable. This case is the first occurrence of non-infiltrating mediastinal angiolipoma reported in Southeast Asia.

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This is the first case report of non-infiltrating mediastinal angiolipoma in Southeast Asia.

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Histopathology examination may be performed by using an invasive or non-invasive procedure.

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In developing countries where VATS cannot be carried out, early complete resection is essential to get favorable outcomes.

Urological Melanoma: A Comprehensive Review of a Rare Subclass of Mucosal Melanoma with Emphasis on Differential Diagnosis and Therapeutic Approaches

Melanoma is reported as the 19th most common cancer worldwide, with estimated age-standardized incidence rates of 2.8-3.1 per 100,000. Although the origin is most frequently cutaneous, mucosal melanoma has been described several times in literature, and despite its rarity (only 1% of all melanomas), increasing attention is being paid to this disease form. Within this subgroup, melanomas of the uropoetic apparatus are a rarity among rarities. Indeed, less than 50 cases of primary melanoma originating from the urinary bladder have been described, and even less originating from the kidney, renal pelvis and urethra. In this work, we present a detailed review of the literature related to this subclass of mucosal melanoma, delve into the biological landscape of this neoplasm and discuss current approaches, future perspectives and potential therapeutic approaches.

The independent indicators for differentiating renal cell carcinoma from renal angiomyolipoma by contrast-enhanced ultrasound

Background

The value of contrast-enhanced ultrasound (CEUS) in differentiating between renal cell carcinoma (RCC) and angiomyolipoma (AML) was analyzed. The purpose of this study was to identify the independent indicators of CEUS for predicting RCC.

Methods

A total of 172 renal tumors (150 RCCs, 22 AMLs) in 165 patients underwent conventional ultrasound (CUS) and CEUS examinations before radical or partial nephrectomy, and the features on CUS and CEUS were analyzed.

Results

There were significant differences in echogenicity, blood flow signals in color Doppler flow imaging (CDFI), peak intensity, homogeneity of enhancement, wash in, wash out, and perilesional rim-like enhancement between RCC and AML (P < 0.05 for all). Multivariate analysis indicated that perilesional rim-like enhancement (P = 0.035, odds ratio [OR] = 9.907, 95% confidence interval [CI]: 1.169–83.971) and fast wash out (P = 0.001, OR = 9.755, 95%[CI]: 2.497–38.115) were independent indicators for predicting RCC. The area under the receiver operating characteristic (ROC) curve (AUC) for perilesional rim-like enhancement was 0.838 (95% CI: 0.774–0.890) with 76.7% sensitivity and 90.9% specificity, while the AUC of fast wash out was 0.833 (95% CI:0.768–0.885) with 74.7% sensitivity and 81.8% specificity.

Conclusions

This study indicated that CEUS has value in differentiating RCC and AML. Present perilesional rim-like enhancement and fast wash out may be important indicators for predicting RCC.

Spontaneous haemorrhage of an adrenal angiomyolipoma: case report

Background

Angiomyolipomas are rare mesenchymal tumours arising from the perivascular epithelioid cells consisting of variable amounts of adipose, thick-walled blood vessels and smooth muscle cells. These benign tumours commonly occur in the kidney with only a few case reports of adrenal angiomyolipomas which have the potential to reach a large size and haemorrhage.

Case presentation

A 45-year-old lady presented with a 3-week history of right loin pain, nausea and vomiting. A CT scan revealed a right adrenal angiomyolipoma measuring 6.3 × 6.8 cm with associated haemorrhage. The lesion was successfully treated with right open adrenalectomy, and histology confirmed the diagnosis of adrenal angiomyolipoma. The patient remained well with no evidence of recurrence at the 36-month follow-up.

Conclusion

Adrenal angiomyolipomas are rare benign tumours that have the ability to reach a large size and potential to bleed. Here, we report the second case of spontaneous haemorrhage in an adrenal angiomyolipoma, which was successfully treated with open adrenalectomy.

A large epithelioid angiomyolipoma of the kidney in a very young child with idiopathic chylothorax: A diagnostic dilemma

Epithelioid angiomyolipoma (EAML) is a subtype of angiomyolipoma, the most common benign renal tumour and usually asymptomatic until adulthood. This paper reports a patient with EAML identified at 30 months, the youngest age of presentation with this tumour reported in the literature. In this case the tumour was extremely large andwas successfully surgically removed. Furthermore, the patient had no other TS features, presented with acute symptoms, and had bilateral idiopathic chylothorax which was managed by octreotide and diet.

PLIN3 is up-regulated and correlates with poor prognosis in clear cell renal cell carcinoma

BACKGROUND

PLIN3, one of the members of the perilipin family, has been reported to be involved in the formation and accumulation of lipid droplets. However, the expression levels and diagnostic and prognostic value of PLIN3 in renal cell carcinoma (RCC) remain unclear.

METHODS

Bioinformatic analysis was used to assess the levels of PLIN3 and the correlation between PLIN3 levels and clinicopathological parameters in renal cancer. The expression levels of PLIN3 were determined in human RCC tissues and cell lines by western blot, immunofluorescence and immunohistochemistry assays. Receiver operating characteristic curves and Kaplan-Meier curves were used to analyze the diagnostic and prognostic significance of PLIN3 in RCC.

RESULTS

The expression level of PLIN3 was elevated in RCC tissues and cell lines, which was consistent with the analysis of the TCGA and Oncomine cancer database. The receiver operating characteristic curve indicated that high PLIN3 expression can distinguish cancer tissues from normal kidney tissues (area under the curve = 0.7270, P<0.0001). Kaplan-Meier curves revealed that elevated PLIN3 predicted poor disease-free survival and overall survival.

CONCLUSIONS

PLIN3 is highly expressed in kidney cancer, and high expression of PLIN3 can serve as a useful diagnostic and prognostic biomarker. PLIN3 functional inhibition can be used as a new clinical treatment option.

Angiomyolipoma of the Kidneys: Current Perspectives and Challenges in Diagnostic Imaging and Image-Guided Therapy

Angiomyolipomas (AML) are benign tumors of the kidneys frequently encountered in radiologic practice in large tertiary centers. In comparison to renal cell carcinomas (RCC), AML are seldom treated unless they are large, undergo malignant transformation or develop complications like acute hemorrhage. The common garden triphasic (classic) AML is an easy diagnosis, however, some variants lack macroscopic fat in which case the radiologic differentiation from RCC becomes challenging. Several imaging features, both qualitative and quantitative, have been described in differentiating the 2 entities. Although minimal fat AML is not entirely a radiologic diagnosis, the suspicion raised on imaging necessitates sampling and potentially avoids an unwanted surgery. Recently a new variant, epitheloid AML has been described which often has atypical imaging features and is at a higher risk for malignant transformation. Apart from the diagnosis, the radiologist also needs to convey information regarding nephrometric scores which help in surgical decision-making. Recently, more and more AMLs are managed with selective arterial embolization and percutaneous ablation, both of which are associated with less morbidity when compared to surgery. The purpose of this article is to review the imaging and pathologic features of classic AML as well as the differentiation of minimal fat AML from RCC. In addition, an overview of nephrometric scoring and image-guided interventions is also provided.

Angiomyolipoma of the Adrenal Gland: A Report of Two Cases and Review of the Literature

BACKGROUND Angiomyolipoma is a benign tumor composed of blood vessels, smooth muscle cells, and adipose tissue and has been described as belonging to the group of tumors of perivascular epithelioid cell origin (PEComa), commonly found in the kidneys and strongly associated with tuberous sclerosis. Only a few cases of extra-renal angiomyolipoma have previously been reported in the literature, most commonly in the liver. Adrenal angiomyolipoma is very rare, is usually asymptomatic, and is often found incidentally, with only 14 previously reported cases identified in the literature. CASE REPORT We report two cases of adrenal angiomyolipoma that were identified by abdominal computed tomography (CT). The first case presented in a 36-year-old man and was an oval-shaped adrenal mass, measuring 5.2×4.2×3.1 cm. The second case presented in a 61-year-old woman and was a round-shaped mass measuring 8.6×9.5×8.1 cm. Both patients underwent adrenalectomy. Histopathology and immunohistochemistry confirmed the diagnosis of benign angiomyolipoma composed of adipose tissues, blood vessels, and smooth muscle cells. CONCLUSIONS We present two rare cases of adrenal angiomyolipoma. We have reviewed the literature and identified 14 other cases of adrenal angiomyolipoma, and discuss the clinical, radiological, and pathological features of this rare tumor.

Changing etiology and management patterns for spontaneous renal hemorrhage: a systematic review of contemporary series

OBJECTIVE

To conduct a systematic literature review on spontaneous renal hemorrhage (SRH) in a contemporary cohort describing patterns in etiology and treatment.

METHODS

A systematic search of MEDLINE and CENTRAL databases was conducted to include articles, including case reports and case series on SRH published from 2000 to 2016. Full-text manuscripts were reviewed for clinical parameters which were collated and analyzed with univariate methods.

RESULTS

Seventy-nine publications met inclusion criteria, reporting on 102 cases. Renal neoplasms (56.9%) and polyarteritis nodosa (PAN) (11.8%) remained as the most common overall and vascular causes of SRH, respectively. Angiomyolipoma (AML) was the most common causative renal neoplasm (74.1%), and patients were more likely to be female and present with macroscopic hematuria than those with vasculitis, while malignant neoplasms were more common in men. Proportions of SRH due to malignant neoplasms (specifically renal cell carcinoma, RCC) were reported less than PAN. Among this contemporary series, transarterial embolization (TAE) was most commonly used for acute SRH (42.2%).

CONCLUSIONS

Renal neoplasms remain as the most common cause of SRH, of which AML predominates, while PAN is currently the second most common etiology in acute SRH, replacing RCC. Minimally invasive approaches, such as TAE and conservative/medical management, were preferred to initial surgery.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration number CRD42017069222.

Dynamic Contrast-enhanced MRI in Renal Tumors: Common Subtype Differentiation using Pharmacokinetics

Preoperative renal tumor subtype differentiation is important for radiology and urology in clinical practice. Pharmacokinetic data (K^trans & V_e, etc.) derived from dynamic contrast-enhanced MRI (DCE-MRI) have been used to investigate tumor vessel permeability. In this prospective study on DCE-MRI pharmacokinetic studies, we enrolled patients with five common renal tumor subtypes: clear cell renal cell carcinoma (ccRCC; n = 65), papillary renal cell carcinoma (pRCC; n = 12), chromophobic renal cell carcinoma (cRCC; n = 9), uroepithelial carcinoma (UEC; n = 14), and fat-poor angiomyolipoma (fpAML; n = 10). The results show that K^trans of ccRCC, pRCC, cRCC, UEC and fpAML (0.459 ± 0.190 min⁻¹, 0.206 ± 0.127 min⁻¹, 0.311 ± 0.111 min⁻¹, 0.235 ± 0.116 min⁻¹, 0.511 ± 0.159 min⁻¹, respectively) were different, but V_e was not. K^trans could distinguish ccRCC from non-ccRCC (pRCC & cRCC) with a sensitivity of 76.9% and a specificity of 71.4%, respectively, as well as to differentiate fpAML from non-ccRCC with a sensitivity of 100% and a specificity of 76.2%, respectively. Our findings suggest that DCE-MRI pharmacokinetics are promising for differential diagnosis of renal tumors, especially for RCC subtype characterization and differentiation between fpAML and non-ccRCC, which may facilitate the treatment of renal tumors.

Sorting the Alphabet Soup of Renal Pathology: A Review

Diseases of the kidney often have their names shortened, creating an arcane set of acronyms which can be confusing to both radiologists and clinicians. This review of renal pathology aims to explain some of the most commonly used acronyms within the field. For each entity, a summary of the clinical features, pathophysiology, and radiological findings is included to aid in the understanding and differentiation of these entities. Discussed topics include acute cortical necrosis, autosomal dominant polycystic kidney disease, angiomyolipoma, autosomal recessive polycystic kidney disease, acute tubular necrosis, localized cystic renal disease, multicystic dysplastic kidney, multilocular cystic nephroma, multilocular cystic renal cell carcinoma, medullary sponge kidney, paroxysmal nocturnal hemoglobinuria, renal papillary necrosis, transitional cell carcinoma, and xanthogranulomatous pyelonephritis.

The diagnostic value of contrast-enhanced ultrasound in differentiating small renal carcinoma and angiomyolipoma

The aim of this study was to explore the value of contrast-enhanced ultrasound (CEUS) in differentiating small renal masses. A total of 102 small renal masses (≤ 3 cm) in 99 patients were examined using conventional ultrasound (CUS) and CEUS, and the findings were reviewed and evaluated in comparison to pathology. Significant differences between renal cell carcinomas (RCCs) and angiomyolipomas (AMLs) were noted in terms of the orientation and echogenicity on CUS (p < 0.05 for both), but the location, shape, margins, homogeneity, and blood flow signals of RCCs on color Doppler flow imaging (CDFI) were similar to those of AMLs (p > 0.05 for all). On CEUS, however, the enhancement intensity, washout in the late phase, and perilesional rim-like enhancement differed significantly for RCCs and AMLs (p = 0.000 for all). Significant differences between CEUS and CUS in terms of sensitivity (88.9% vs. 55.6%), the negative predictive value (68.0% vs. 29.5%), the false negative rate (9.9% vs. 44.5%), and accuracy (88.3% vs. 58.9%) were noted (p < 0.05 for all). CEUS, with its unique features, has value in diagnosing small RCCs and AMLs and outperforms CUS in differentiation of small RCCs and AMLs.

Clinical presentation, management, and outcome of patients with incidental renal angiomyolipoma in qatar

OBJECTIVES

Our study aimed to analyze the clinical presentation, management, and outcome of renal angiomyolipoma patients incidentally detected upon computed tomography (CT) examination.

METHODS

Between 2004 and 2008, all patients who underwent abdominal CT examination for any reason at the radiology department at Hamad General Hospital, Qatar were retrospectively reviewed. The diagnosis of renal angiomyolipoma was based on abdominal CT evaluation. Angiomyolipoma patients were followed-up by CT evaluation as per standard care for three years to observe any change in size and outcome.

RESULTS

A total of 13,115 patients were screened, of which 56 (40 females and 16 males) had renal angiomyolipoma. The mean age of patients was 52±13 years with 46% Qatar nationals. The majority (95%) of cases had unilateral tumors (52% right-sided and 43% left-sided). Twenty-six cases showed increase in tumor size and the median increase was 0.5cm (0.1-3.6). Surgical intervention was required in four (7%) cases with tumor size ≥4cm. The overall mortality on follow-up was 7%. The cause of death included metastasis, renal failure, hepatic failure and mesenteric thromboembolism.

CONCLUSION

Renal angiomyolipoma is an uncommon benign tumor with an overall prevalence of 0.4% in Qatar. It has characteristic clinical features and its recognition is often challenging for proper clinical diagnosis and treatment in asymptomatic patients. Asymptomatic patients need regular radiological surveillance. In contrast, surgical interventions are mainly required in symptomatic patients with increased tumor size (≥4cm). Timely diagnosis and treatment is necessary to avoid complications such retroperitoneal hemorrhage and renal impairment.

Surgical management of haemorrhaging renal angiomyolipoma in pregnancy

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We report the case of a 25-week pregnant woman that had a ruptured AML.

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This is the first case of nephrectomy in late second trimester with the foetus left in-utero.

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We present a literature review of the management of bleeding AML in pregnancy.

Introduction

Renal angiomyolipoma (AML) is a benign mesenchymal tumour of the kidney with a tendency of aneurysm formation at risk of rupturing. Due to increased maternal circulation and hormonal influences, rupture risk is greater in pregnancy, often leading to a vascular emergency and premature delivery or termination.

Presentation of case

A 24-weeks pregnant woman (45 years old, G6P1) presented with haematuria and flank pain. CT showed AML with acute haemorrhage. The patient became haemodynamically unstable and underwent urgent embolisation and follow-on total radical nephrectomy with the foetus being left in-utero. This involved a multidisciplinary team (urologist, vascular surgeon, interventional radiologist and obstetrician). The procedure was uncomplicated and the pregnancy went to term with a healthy girl delivered at 38 weeks.

Discussion

The incidence of AML is 0.13% in the general population. 21 reports of haemorrhaging AML in pregnancy have been published in the last 35 years. Mean gestational age was 29.6 weeks. Eight were treated conservatively to term, one underwent exploratory laparotomy with evacuation of haematoma only, five were embolised, and seven were managed with nephrectomy. Of the nephrectomy subgroup, one was preceded by vaginal delivery and five underwent concurrent caesarean section (one with pre-op embolisation). There were two associated foetal deaths.

Conclusion

This case demonstrates that with a multidisciplinary approach, it is possible to successfully leave a foetus undelivered whilst performing a radical nephrectomy for a large bleeding AML in a woman carrying a late second trimester pregnancy.