Development and internal validation of a clinical risk score to predict incident renal and pulmonary tumours in people with tuberous sclerosis complex.

OBJECTIVE: This study aims to develop and internally validate a clinical risk score to predict incident renal angiomyolipoma (AML) and pulmonary lymphangioleiomyomatosis (LAM) in people with tuberous sclerosis complex (TSC). STUDY DESIGN: Data from 2420 participants in the TSC Alliance Natural History Database were leveraged for these analyses. Logistic regression was used to predict AML and LAM development using 10 early-onset clinical manifestations of TSC as potential predictors, in addition to sex and genetic mutation. For our models, we divided AML into three separate outcomes: presence or absence of AML, unilateral or bilateral and whether any are ≥3 cm in diameter. The resulting regression models were turned into clinical risk scores which were then internally validated using bootstrap resampling, measuring discrimination and calibration. RESULTS: The lowest clinical risk scores predicted a risk of AML and LAM of 1% and 0%, while the highest scores predicted a risk of 99% and 73%, respectively. Calibration was excellent for all three AML outcomes and good for LAM. Discrimination ranged from good to strong. C-statistics of 0.84, 0.83, 0.83 and 0.92 were seen for AML, bilateral AML, AML with a lesion≥3 cm and LAM, respectively. CONCLUSION: Our work is an important step towards identifying individuals who could benefit from preventative strategies as well as more versus less frequent screening imaging. We expect that our work will allow for more personalised medicine in people with TSC. External validation of the risk scores will be important to confirm the robustness of our findings.

High-frame-rate contrast-enhanced ultrasound to differentiate between clear cell renal cell carcinoma and angiomyolipoma.

BACKGROUND: To investigate the diagnostic efficacy of high-frame-rate contrast-enhanced ultrasound (H-CEUS) in differentiating between clear cell renal cell carcinoma (CCRCC) and angiomyolipoma (AML). METHODS: A retrospective study was performed on the clinical data of 79 patients diagnosed with CCRCC and 31 patients diagnosed with AML at the First Affiliated Hospital of Nanchang University between October 2022 and December 2023. Conventional ultrasound (US) and H-CEUS examinations were conducted on all patients prior to surgery, dynamic images were recorded from the US, and the qualitative and quantitative parameters of H-CEUS were collected. The t-test, χ² test and non-parametric Mann-Whitney test were employed to assess differences in clinical data, US characteristics, and qualitative and quantitative parameters of H-CEUS between the CCRCC and AML groups. The independent risk factors of CCRCC were identified using binary logistic regression. The receiver operator characteristic (ROC) curve was constructed to evaluate the diagnostic effectiveness of clinical + US and H-CEUS in differentiating between CCRCC and AML. RESULTS: The CCRCC group and the AML group exhibited significant differences in patient gender, operation mode, nodular echo, and nodule blood flow (χ²=11.698, -, -,=10.582; P<0.001, <0.001, <0.001, and = 0.014, respectively). In addition, the H-CEUS qualitative analysis demonstrated significant differences between the AML group and the CCRCC group with respect to enhancement mode, regression mode, peak intensity, enhancement uniformity, no enhancement, and presence or absence of pseudocapsule (χ²=41.614, -, -, = 2.758, = 42.099, -; P<0.001, <0.001, <0.001, 0.097, <0.001, and <0.001, respectively). The Arrival time (AT) in the CCRCC group was significantly shorter than that in the AML group, as determined by quantitative analysis of H-CEUS (Z=-3.266, P = 0.001). Furthermore, the Peak intensity (PI), Ascent slope (AS), and The area under the curve (AUC) exhibited significantly higher values in the CCRCC group compared to the AML group (Z=-2.043,=-2.545,=-3.565; P = 0.041, = 0.011, and <0.001, respectively). Logistic regression analysis indicated that only gender, nodule echo, the pseudocapsule, AS, and AUC of H-CEUS were independent risk factors of CCRCC. The ROC curve revealed that combining gender and nodule echo yielded a sensitivity of 92.4%, specificity of 64.5%, and an AUC of 0.847 in distinguishing between CCRCC and AML. When combining the H-CEUS parameters of pseudocapsule, AS, and AUC, the sensitivity, specificity, and AUC for distinguishing between CCRCC and AML were 84.8%, 96.8%, and 0.918, respectively. No statistically significant difference was observed in the diagnostic effectiveness of the two methods (Z=-1.286, P = 0.198). However, H-CEUS demonstrated better AUC and specificity. CONCLUSIONS: H-CEUS enhances the sensitivity and specificity of differentiating between CCRCC and AML by improving the temporal resolution, offering a more precise diagnostic foundation for identifying the most appropriate therapy for patients.

New staging criteria predicting m-tor inhibitors treatment effect of renal angiomyolipoma in tuberous sclerosis complex patients.

BACKGROUND: We aimed to launched new staging criteria to predict mTOR inhibitors treatment effect of renal angiomyolipomas (r-AMLs) in TSC patients. METHODS: 40 TSC patients with 69 r-AMLs were divided into two groups based on the efficacy of 6-month mTOR inhibitor treatment. Epidemiological data, therapeutic response, and predictive factors of enrolled patients were collected and analyzed. Age, sex, maximum diameter, maximum cross-sectional area (CSAmax), unenhanced mean CT value, enhanced mean CT value, and added value of enhanced CT of largest r-AML at baseline were assessed as potential influencing factors. Receiver operating characteristic (ROC) curve analysis and the area under the ROC curve (AUC) was used to estimate prediction power. RESULTS: After 6 months of mTOR inhibitor treatment, the tumor reduction rates in the two groups were 55.87% and 16.44% (P < 0.001). At the start of treatment, the maximum diameters, CSAmax, added value of enhanced CT of the target lesion in two groups were 7.70 ± 0.73 cm vs. 13.18 ± 1.23 cm(P = 0.028), 57.40 ± 10.76cm2 vs. 167.29 ± 33.09cm2 (P = 0.015), and 62.32 ± 5.03HU vs. 33.06 ± 3.13HU (P = 0.009), respectively. AUCs of CSAmax, added value of enhanced CT, and combination of both were 0.8024, 0.7672, and 0.8116, respectively (P < 0.001). Cut-off values of CSAmax combined with the added value of enhanced CT were 40cm2 and 46HU. AUCs of maximum diameters, combination of maximum diameters and added value of enhanced CT were 0.7600 and 0.8100, respectively (P < 0.001), with cut-off values of 6.6 cm and 46 HU. CONCLUSION: New staging criteria, based on CSAmax and added value of enhanced CT, can predict the treatment efficiency of m-TOR inhibitors for r-AMLs in TSC patients. A simplified version based on maximum diameter and added value of enhanced CT of lesion has also been proposed.

Evolving horizons in renal angiomyolipoma: two decades of management strategies and clinical perspectives in a single institutional study.

OBJECTIVE: To assess various management options for renal angiomyolipoma (AML) to guide clinical practice. METHODS: A single center retrospectively reviewed an AML series from 2002 to 2022. The image reports and chart reviews of patients who received two abdominal scans at least 6 months between the first and last scans were assessed. RESULTS: A total of 203 patients with 209 tumors were identified and followed up for a median of 42.6 months. Active surveillance (AS) was the most frequently selected option (70.9% of cases). Interventions were required for 59 AMLs, of which 20 were treated with embolization, 29 with partial nephrectomy, 9 with radical nephrectomy, and 1 with radiofrequency (RF) ablation. The median size of the lesions at intervention was 5 cm. The average growth rate of the lesions was 0.12 cm/year, and there was a significant difference in the average growth rate of lesions ≤4 cm and those >4 cm (0.11 vs. 0.24 cm/year; p = 0.0046). CONCLUSION: This series on AMLs confirms that lesions >4 cm do not require early intervention based on size alone. Appropriately selected cases of renal AML can be managed by AS.KEYWORDS: Angiomyolipoma; active surveillance; embolization; nephrectomy; nephron-sparing surgery.

The extent of kidney involvement in paediatric tuberous sclerosis complex.

BACKGROUND: Tuberous sclerosis (TSC)-associated kidney disease is a leading cause of mortality in adults with TSC. This study aimed to understand TSC features in children, particularly kidney involvement, to inform clinical care for this specific group. METHODS: This retrospective cohort study included all paediatric (< 19 years) TSC cases at a large tertiary paediatric nephrology centre. Relevant data were collected from patients' records, statistical analyses were performed to identify associations between variables, survival probabilities were estimated with Kaplan‒Meier curves, and log-rank tests were conducted to assess survival differences among genetic mutations. RESULTS: A total of 182 children with TSC were included. Among the 145 children with available kidney imaging data, 78.6% (114/145) exhibited kidney lesions. Angiomyolipomas (AMLs) were significantly more prevalent in the TSC2 mutation group (p = 0.018). Children with TSC2 mutations generally had poorer lesion-free survival than those with TSC1 mutations, but this difference was only significant for AMLs (p = 0.030). The change in size of largest AMLs increased with age and doubled in children above 9 years; a similar pattern was observed when stratified by genetic mutation. In contrast, kidney cysts exhibited two peaks: one in children under 5 years (2.31 mm/year) and the second in children between 15-19 years (2.82 mm/year). Chronic kidney disease was observed in 12.3% (10/81) of children, and high-risk AMLs above 3 cm were observed in 9% (13/145). CONCLUSIONS: While TSC kidney disease emerges later in the disease course than neurological features, our findings emphasise the importance of kidney surveillance during childhood, including routine kidney imaging, kidney function, and blood pressure monitoring.

Frequency of benign tumors after partial nephrectomy and the association between malignant tumor findings and preoperative clinical parameters.

BACKGROUND: Partial nephrectomy (PN) has become the dominant treatment modality for cT1 renal tumor lesions. Tumors suspected of malignant potential are indicated for surgery, but some are histologically classified as benign lesions after surgery. This study aims to analyze the number of benign findings after PN according to definitive histology and to evaluate whether there is an association between malignant tumor findings and individual factors. METHODS: The retrospective study included 555 patients who underwent open or robotic-assisted PN for a tumor in our clinic from January 2013 to December 2020. The cohort was divided into groups according to definitive tumor histology (malignant tumors vs. benign lesions). The association of factors (age, sex, tumor size, R.E.N.A.L.) with the malignant potential of the tumor was further evaluated. RESULTS: In total, 462 tumors were malignant (83%) and 93 benign (17%). Of the malignant tumors, 66% were clear-cell RCC (renal cell carcinoma), 12% papillary RCC, and 6% chromophobe RCC. The most common benign tumor was oncocytoma in 10% of patients, angiomyolipoma in 2%, and papillary adenoma in 1%. In univariate analysis, there was a higher risk of malignant tumor in males (OR 2.13, 95% CI 1.36-3.36, p = 0.001), a higher risk of malignancy in tumors larger than 20 mm (OR 2.32, 95% CI 1.43-3.74, p < 0.001), and a higher risk of malignancy in tumors evaluated by R.E.N.A.L. as tumors of intermediate or high complexity (OR 2.8, 95% CI 1.76-4.47, p < 0.001). In contrast, there was no association between older age and the risk of malignant renal tumor (p = 0.878). CONCLUSIONS: In this group, 17% of tumors had benign histology. Male sex, tumor size greater than 20 mm, and intermediate or high R.E.N.A.L. complexity were statistically significant predictors of malignant tumor findings.

The effect of pregnancy on renal angiomyolipoma; a world of knowledge to gain, specifically in women with TSC.

BACKGROUND: Women are counseled preconceptionally about the potential risks of rAML progression and chance of complications during and due to pregnancy. However, a systematic search investigating the evidence on which this advice is based does not exist. The aim of this systematic review is to determine the effect of pregnancy on renal angiomyolipoma (rAML) size and risk of haemorrhage in patients with tuberous sclerosis complex (TSC). METHODS: We searched PubMed, EMBASE, Medline and ClinicalTrials.gov using terms for "renal angiomyolipoma" and "pregnancy". English-language articles published between January 1st 2000, and December 31st 2020 of which full-text was available were included. The initial search resulted in 176 articles. After the screening process we included 45 case reports and 1 retrospective study. For the retrospective study we assessed the risk of bias using the Newcastle-Ottawa Scale. We included articles about renal AML and pregnancy with and without an established diagnosis of TSC. From these articles we recorded the rAML sizes and rAML complications. RESULTS: Seven case reports, from a total of 45 case reports, provided follow-up data on renal AML size (these were all cases of renal AML without a known diagnosis of TSC). Of these cases, renal AML size decreased in one patient, was stable in one patient, increased in three patients and fluctuated in two others. Renal AML size of women who suffered a haemorrhage were significantly larger (12.1 ± 4.6 cm) than rAMLs of women who did not suffer a haemorrhage (8.3 ± 3.2 cm). Data from the retrospective study showed no difference in renal complications between the women with and without a history of pregnancy. Haemorrhage occurred in 30% of the women with a history of pregnancy (n = 20) and in 11% in the patients without a history of pregnancy (n = 2), however this retrospective study had methodological limitations. CONCLUSION: The effect of pregnancy on renal AML size and complications in patients with TSC is unclear. More research is needed to determine the risk of pregnancy on TSC-associated kidney disease in TSC patient.

Stepwise algorithm using computed tomography and magnetic resonance imaging for differential diagnosis of fat-poor angiomyolipoma in small renal masses: A prospective validation study.

OBJECTIVES: To validate the diagnostic accuracy of a stepwise algorithm to differentiate fat-poor angiomyolipoma (fp-AML) from renal cancer in small renal masses (SRMs). METHODS: We prospectively enrolled 223 patients with solid renal masses <4 cm and no visible fat on unenhanced computed tomography (CT). Patients were assessed using an algorithm that utilized the dynamic CT and MRI findings in a stepwise manner. The diagnostic accuracy of the algorithm was evaluated in patients whose histology was confirmed through surgery or biopsy. The clinical course of the patients was further analyzed. RESULTS: The algorithm classified 151 (68%)/42 (19%)/30 (13%) patients into low/intermediate/high AML probability groups, respectively. Pathological diagnosis was made for 183 patients, including 10 (5.5%) with fp-AML. Of these, 135 (74%)/36 (20%)/12 (6.6%) were classified into the low/intermediate/high AML probability groups, and each group included 1 (0.7%)/3 (8.3%)/6 (50%) fp-AMLs, respectively, leading to the area under the curve for predicting AML of 0.889. Surgery was commonly opted in the low and intermediate AML probability groups (84% and 64%, respectively) for initial management, while surveillance was selected in the high AML probability group (63%). During the 56-month follow-up, 36 (82%) of 44 patients initially surveyed, including 13 of 18 (72%), 6 of 7 (86%), and 17 of 19 (89%) in the low/intermediate/high AML probability groups, respectively, continued surveillance without any progression. CONCLUSIONS: This study confirmed the high diagnostic accuracy for differentiating fp-AMLs. These findings may help in the management of patients with SRMs.

[Discussion on the surgical timing of rupture and hemorrhage of renal angiomyolipoma].

OBJECTIVE: To investigate the effect of different surgical timing on the surgical treatment of renal angiomyolipoma (RAML) with rupture and hemorrhage. METHODS: The demographic data and perioperative data of 31 patients with rupture and hemorrhage of RAML admitted to our medical center from June 2013 to February 2023 were collected. The surgery within 7 days after hemorrhage was defined as a short-term surgery group, the surgery between 7 days and 6 months after hemorrhage was defined as a medium-term surgery group, and the surgery beyond 6 months after hemorrhage was defined as a long-term surgery group. The perioperative related indicators among the three groups were compared. RESULTS: This study collected 31 patients who underwent surgical treatment for RAML rupture and hemorrhage, of whom 13 were males and 18 were females, with an average age of (46.2±11.3) years. The short-term surgery group included 7 patients, the medium-term surgery group included 12 patients and the long-term surgery group included 12 patients. In terms of tumor diameter, the patients in the long-term surgery group were significantly lower than those in the recent surgery group [(6.6±2.4) cm vs. (10.0±3.0) cm, P=0.039]. In terms of operation time, the long-term surgery group was significantly shorter than the mid-term surgery group [(157.5±56.8) min vs. (254.8±80.1) min, P=0.006], and there was no significant difference between other groups. In terms of estimated blood loss during surgery, the long-term surgery group was significantly lower than the mid-term surgery group [35 (10, 100) mL vs. 650 (300, 1 200) mL, P < 0.001], and there was no significant difference between other groups. In terms of intraoperative blood transfusion, the long-term surgery group was significantly lower than the mid-term surgery group [0 (0, 0) mL vs. 200 (0, 700) mL, P=0.014], and there was no significant difference between other groups. In terms of postoperative hospitalization days, the long-term surgery group was significantly lower than the mid-term surgery group [5 (4, 7) d vs. 7 (6, 10) d, P=0.011], and there was no significant difference between other groups. CONCLUSION: We believe that for patients with RAML rupture and hemorrhage, reoperation for more than 6 months is a relatively safe time range, with minimal intraoperative bleeding. Therefore, it is more recommended to undergo surgical treatment after the hematoma is systematized through conservative treatment.

[Clinical diagnosis and treatment of renal angiomyolipoma with inferior vena cava tumor thrombus].

OBJECTIVE: To summarize the clinical characteristics of patients with renal angiomyolipoma (RAML) combined with inferior vena cava (IVC) tumor thrombus, and to explore the feasibility of partial nephrectomy and thrombectomy in this series of patients. METHODS: The clinical data of patients diagnosed with RAML combined with IVC tumor thrombus in the Department of Urology of the Peking University Third Hospital from April 2014 to March 2023 were retrospectively analyzed, and demographic and perioperative data of RAML patients with IVC tumor thrombus were recorded and collected from Electronic Medical Record System, including age, gender, surgical methods, and follow-up time, etc. The clinical characteristics between classic angiomyolipoma (CAML) patients with IVC tumor thrombus and epithelioid angiomyolipoma (EAML) patients with IVC tumor thrombus were compared to determine the clinical characteristics of these patients. RESULTS: A total of 11 patients were included in this study, including 7 patients with CAML with IVC tumor thrombus and 4 patients with EAML with IVC tumor thrombus. There were 9 females (9/11, 81.8%) and 2 males (2/11, 18.2%), with an average age of (44.0±17.1) years. 9 patients (9/11, 81.8%) experienced clinical symptoms, including local symptoms including abdominal pain, hematuria, abdominal masses, and systemic symptoms including weight loss and fever; 2 patients (2/11, 18.2%) with RAML and IVC tumor thrombus did not show clinical symptoms, which were discovered by physical examination. Among the 11 patients, 10 underwent radical nephrectomy with thrombectomy, of whom, 3 underwent open surgery (3/10, 30.0%), 2 underwent laparoscopic surgery (2/10, 20.0%), and 5 underwent robot-assisted laparoscopic surgery (5/10, 50.0%). In addition, 1 patient underwent open partial nephrectomy and thrombectomy. The patients with EAML combined with IVC tumor thrombus had a higher proportion of systemic clinical symptoms (100% vs. 0%, P=0.003), more intraoperative bleeding [400 (240, 3 050) mL vs. 50 (50, 300) mL, P =0.036], and a higher proportion of tumor necrosis (75% vs. 0%, P=0.024) compared to the patients with CAML combined with IVC tumor thrombus. However, there was no statistically significant difference in operation time [(415.8±201.2) min vs. (226.0±87.3) min, P=0.053] between the two groups. CONCLUSION: Compared with the patients with CAML and IVC tumor thrombus, the patients with EAML and IVC tumor thrombus had a higher rate of systemic symptoms and tumor necrosis. In addition, in the selected patients with CAML with IVC tumor thrombus, partial nephrectomy and tumor thrombectomy could be performed to better preserve renal function.

Microscopic Kidney Disease in Tuberous Sclerosis Complex and Treatment With mTOR Inhibition.

Declining kidney function in tuberous sclerosis complex (TSC) is often attributed to large lesions, including angiomyolipomas (AMLs) and cysts, that encroach on the normal parenchyma or that require intervention and loss of parenchyma from surgical debulking or embolization. Consequently, research on inhibitors of the mammalian target of rapamycin (mTOR), a protein complex implicated in TSC pathophysiology for its role in promoting cell growth and proliferation, has largely focused on their ability to reduce AML size. Clinical guidelines distilled from this research limit mTOR inhibition as a first-line treatment to patients with large AMLs. However, chronic kidney disease (CKD) occurs in patients without large AMLs or a history of renal intervention. Alternate mechanisms postulated for CKD in TSC may suggest a role for mTOR inhibition in this population. In this report, we present 2 cases of a microscopic variant of TSC kidney disease causing declining kidney function, as well as anecdotal evidence for the use of mTOR inhibition to improve kidney function in the absence of large AMLs. We highlight the importance of annual kidney function assessment in patients with TSC and suggest a low threshold for kidney biopsy in patients with declining glomerular filtration rate without a clear etiology clinically or radiographically.

Alkaline phosphatase combines with CT factors for differentiating small (≤ 4 cm) fat-poor angiomyolipoma from renal cell carcinoma: a multiple quantitative tool.

PURPOSE: This study aimed to evaluate the diagnostic value of serum and CT factors to establish a convenient diagnostic method for differentiating small (≤ 4 cm) fat-poor angiomyolipoma (AML) from renal cell carcinoma (RCC). MATERIALS AND METHODS: This study analyzed the preoperative serum laboratory data and CT data of 32 fat-poor AML patients and 133 RCC patients. The CT attenuation value of tumor (AVT), relative enhancement ratio (RER), and heterogeneous degree of tumor were detected using region of interest on precontrast phase (PCP) and the corticomedullary phase. Multivariate regression was performed to filter the main factors. The main factors were selected to establish the prediction models. The area under the curve (AUC) was measured to evaluate the diagnostic efficacy. RESULTS: Fat-poor AML was more common found in younger (47.91 ± 2.09 years vs 53.63 ± 1.17 years, P = 0.02) and female (70.68 vs 28.13%, P < 0.001) patients. Alkaline phosphatase (ALP) was higher in RCC patients (81.80 ± 1.75 vs 63.25 ± 2.95 U/L, P < 0.01). For CT factors, fat-poor AML was higher in PCP_AVT (40.30 ± 1.49 vs 32.98 ± 0.69Hu, P < 0.01) but lower in RER (67.17 ± 3.17 vs 84.64 ± 2.73, P < 0.01). Gender, ALP, PCP_AVT and RER was found valuable for the differentiation. When compared with laboratory-based or CT-based diagnostic models, the combination model integrating gender, ALP, PCP_AVT and RER shows the best diagnostic performance (AUC = 0.922). CONCLUSION: ALP was found higher in RCC patients. Female patients with ALP < 70.50U/L, PCP_AVT > 35.97Hu and RER < 82.66 are more likely to be diagnose as fat-poor AML.

A systematic review and meta-analysis of spectral CT to differentiate focal liver lesions.

AIM: To determine the feasibility of spectral computed tomography (CT) in the differentiation of focal liver lesions from hepatocellular carcinoma (HCC) using a network meta-analysis (NMA). MATERIALS AND METHODS: The review was completed in accordance with PRISMA guidelines. Searches of three medical databases were performed. A total of nine articles were found for the qualitative synthesis. The meta-analysis was performed on five studies for the normalised iodine concentration (NIC; which is the iodine concentration in the lesion divided by the iodine concentration in the aorta) and the lesion-normal parenchyma iodine ratio (LNR; which is the iodine concentration in the lesion divided by the iodine concentration in the non-tumour hepatic parenchyma) on portal venous and arterial phase images due to sufficient data. RESULTS: Spectral CT can be used to differentiate HCC from hepatic haemangioma (HH), focal nodular hyperplasia (FNH), regenerative nodules, neuroendocrine tumours (NETs), abscesses, and angiomyolipoma (AML). Hepatic metastases versus abscess and FNH versus HH could also be differentiated. The NMA demonstrated that HCC, NETs, and regenerative nodules could be differentiated due to lower quantitative iodine values. FNH, AML, and HH all had higher values. CONCLUSION: Spectral CT shows promise in differentiating focal liver lesions. Studies with larger sample sizes are warranted. Future studies should be performed comparing benign lesions using quantitative markers.

Serum lactate dehydrogenase concentration after transcatheter renal artery embolization correlates with reduction in renal angiomyolipoma volume.

BACKGROUND: The extent of renal angiomyolipoma (AML) volume reduction after renal transcatheter arterial embolization (TAE) varies between patients, with no predictive measure available. PURPOSE: To determine whether the serum lactate dehydrogenase (LDH) concentration shortly after TAE correlates with the extent of tumor shrinkage. MATERIAL AND METHODS: In a cohort of 36 patients undergoing prophylactic renal TAE for unruptured renal AML, we retrospectively acquired data from patient medical records, including serum LDH before and within 7 days after TAE and the tumor volume before and 12-36 months after TAE. The relationship between the serum level of LDH and reduction in tumor volume was evaluated using Spearman correlation analysis. RESULTS: The median LDH concentration was significantly higher after TAE than before (909.0 U/L vs. 186.5 U/L). This early post-TAE serum LDH level and LDH index (post-TAE LDH / pre-TAE LDH) correlated significantly and positively with the absolute decrease in tumor volume (both P < 0.0001). We observed no significant correlation between the relative tumor volume reduction and serum LDH level or LDH index. CONCLUSION: Serum LDH elevation occurs shortly after TAE and correlates with the extent of absolute decrease in AML volume at 12-36 months after TAE. Further large-scale studies are warranted to confirm the predictive role of post-TAE serum LDH level and LDH index in tumor shrinkage in patients with unruptured renal AML.

Shear wave elastography in the characterization of renal cell carcinoma and angiomyolipoma.

BACKGROUND: Detection and characterization of renal lesions are common in daily clinical practice. PURPOSE: To investigate the effectiveness of shear wave elastography (SWE), a novel radiological examination technique, in the characterization of renal masses. MATERIAL AND METHODS: The study included a total of 68 patients (33 men, 35 women; mean age = 57.71 ± 12.08 years; age range = 19-83 years) who underwent SWE. SWE measurements were obtained at depths of 2-8 cm from the probe surface in two different positions from an analysis window of approximately 0.5 × 1.0 cm on ultrasound. The cutoff SWE was calculated for the differentiation of renal cell carcinoma (RCC) and angiomyolipoma (AML) by receiver operating characteristic (ROC) analysis. When the result was statistically significant, the sensitivity, specificity, accuracy, and positive and negative predictive values of the test were calculated. RESULTS: Mass-to-parenchyma SWE ratios of RCCs were significantly higher than those of AMLs (P = 0.003). In ROC curve analysis, the SWE cutoff was 1.215 m/s to differentiate RCCs from AMLs. The area under the ROC curve was calculated as 0.74 (95% CI = 0.610-0.871, sensitivity = 70.7%, specificity = 70.6%, positive predictive value = 87.8%, negative predictive value = 44.4%). CONCLUSION: The SWE technique is increasingly used and may be useful in distinguishing RCC and AML lesions, and especially clear cell and non-clear cell RCCs.

Diagnostic Value of Qualitative and Quantitative Contrast-Enhanced Ultrasound for Pathological Subtypes of Small Solid Renal Masses.

OBJECTIVES: To assess the diagnostic value of qualitative and quantitative contrast-enhanced ultrasound (CEUS) for pathological subtypes of small solid renal masses (sSRMs). METHODS: Patients with sSRMs confirmed by surgical pathology from January 2019 to November 2021 were retrospectively identified. All patients were divided into 3 groups: clear cell renal cell carcinoma (ccRCC) group, none-ccRCC group (renal cell carcinoma other than ccRCC), and angiomyolipoma (AML) group. The mass position, size, echogenicity and blood flow signals were compared. The speed of wash-in, wash-out, the degree of peak enhancement and the homogeneity at peak enhancement, the presence of pseudocapsule sign in CEUS imaging were qualitatively evaluated. Peak enhancement, wash-in area under the curve (WiAUC), rise time, time to peak, wash-in rate (WiR), wash-in perfusion index (WiPI) and tumor-to-cortex enhancement ratio of the above parameters in CEUS imaging were quantitatively evaluated. RESULTS: Of 105 patients, 105 sSRMs (66 ccRCC, 18 none-ccRCC, 21 AML) were enrolled in this study. No significant differences were found on location, size and echogenicity among 3 groups (all P > .05). The proportion of fast-washout and hypo-enhancement were highest in none-ccRCC group. Heterogeneous enhancement was detected in 87.88% in ccRCC group which is significantly higher than other 2 groups. Hundred percent of the AML showed no pseudocapsule sign, which is the highest among the 3 groups. Peak enhancement, WiAUC, WiR, WiPI of ccRCC group were the highest among the 3 groups. CONCLUSIONS: Qualitative and quantitative CEUS not only has the diagnostic value in distinguishing AML from malignant sSRMs, but also helps to differentiate the pathological subtypes of sSRMs.

Are There Ultrasound Features to Distinguish Small (<3 cm) Peripheral Renal Angiomyolipomas From Renal Cell Carcinomas?

BACKGROUND: Small echogenic renal masses are usually angiomyolipomas (AMLs), but some renal cell carcinomas (RCCs) can be echogenic and confused with an AML. OBJECTIVES: This is a study to evaluate any distinguishing demographic and sonographic features of small (<3 cm) peripheral AMLs versus peripheral RCCs. METHODS: This is a HIPAA-compliant retrospective review of the demographics and ultrasound features of peripheral renal AMLs compared with a group of peripheral RCCs. All AMLs had confirmation of macroscopic fat as noted on thin-cut CT or fat-saturation MRI sequence images. All RCCs were pathologically proven. Statistical analysis was used to compare findings in the two groups. RESULTS: There were a total of 52 patients with 56 AMLs, compared with 42 patients with 42 RCCs. There were 42 females in the AML group versus 10 females in the RCC group (P < .0001). The AML diameters (15.7 mm × 12.0 mm) were statistically significantly smaller (Plargest = .0085, Psmallest < .001) than the diameters of the RCCs (19.9 mm × 18.5 mm). Ultrasound features found to be statistically different between the two groups were the ratio of the largest dimension to the smallest dimension (P < .001), a lobulated versus smooth margin of the AML (26 vs 30) compared with the RCC group (3 vs 39) (P = .0012), and an "unusual" versus a round shape (P < .001) of the AML group (45 vs 11) compared with the RCC group (9 vs 33). In the multivariable model, the patient sex, margin, and mass shape were predictive of AML, with an area under the receiver operating characteristic curve of 0.92. CONCLUSION: For a small (<3 cm) peripheral echogenic mass in a female patient, a lobulated lesion with an unusual shape is highly predictive of being an AML.

Malignant Pigmented Epithelioid Angiomyolipoma of the Kidney in a Child with Tuberous Sclerosis Complex.

INTRODUCTION: Pigmented epithelioid angiomyolipoma is a variant of epithelioid angiomyolipoma (EAML) that has not previously been described in children with tuberous sclerosis. CASE PRESENTATION: A 15-year-old boy with tuberous sclerosis had a rapidly enlarging renal mass associated with a left lung nodule. Microscopically it was a pigmented EAML, confirmed by immunohistochemistry. DISCUSSION/CONCLUSION: The pigmented variant of EAML can arise and metastasize from the kidney of a teenager with tuberous sclerosis.

[Angiomyolipoma of the liver]. / Angiomiolipoma pecheni.

Angiomyolipoma of the liver is an extremely rare neoplasm, the number of reported cases of this disease is only about 600 worldwide. Morphological criteria for neoplasm verification present difficulties due to low occurrence and complexity of differential diagnostic search. In this regard, this observation is of interest to pathologists and physicians. A special feature of this tumor is the presence of three components: adipose, vascular and muscular with characteristic epithelioid cells. The article presents the clinical and morphological characteristics of liver angiomyolipoma in a 40-year-old woman. The diagnosis was confirmed by immunohistochemical study: a positive reaction with HMB45, Melan A, SMA, desmin, CD31, CD34; proliferative index was more than 25%.

High-throughput screening of circRNAs reveals novel mechanisms of tuberous sclerosis complex-related renal angiomyolipoma.

OBJECTIVE: Tuberous sclerosis complex (TSC) is a rare autosomal dominant disease characterized by lesions throughout the body. Our previous study showed the abnormal up-regulation of miRNAs plays an important part in the pathogenesis of TSC-related renal angiomyolipoma (TSC-RAML). circRNAs were known as important regulators of miRNA, but little is known about the circRNAs in TSC-RAMLs. METHODS: Microarray chips and RNA sequencing were used to identify the circRNAs and mRNAs that were differently expressed between the TSC-RAML and normal kidney tissue. A competitive endogenous RNA (ceRNA) regulatory network was constructed to reveal the regulation of miRNAs and mRNAs by the circRNAs. The biological functions of circRNA and mRNA were analyzed by pathway analysis. Microenvironmental cell types were estimated with the MCP-counter package. RESULTS: We identified 491 differentially expressed circRNAs (DECs) and 212 differentially expressed genes (DEGs), and 6 DECs were further confirmed by q-PCR. A ceRNA regulatory network which included 6 DECs, 5 miRNAs, and 63 mRNAs was established. Lipid biosynthetic process was significantly up-regulated in TSC-RAML, and the humoral immune response and the leukocyte chemotaxis pathway were found to be down-regulated. Fibroblasts are enriched in TSC-RAML, and the up-regulation of circRNA_000799 and circRNA_025332 may be significantly correlated to the infiltration of the fibroblasts. CONCLUSION: circRNAs may regulate the lipid metabolism of TSC-RAML by regulation of the miRNAs. Fibroblasts are enriched in TSC-RAMLs, and the population of fibroblast may be related to the alteration of circRNAs of TSC-RAML. Lipid metabolism in fibroblasts is a potential treatment target for TSC-RAML.