Observational study of characteristics and clinical outcomes of Dutch patients with tuberous sclerosis complex and renal angiomyolipoma treated with everolimus.

OBJECTIVE: To compare kidney size (used as proxy for total renal angiomyolipoma [rAML] size) and kidney function outcomes between patients with tuberous sclerosis complex (TSC) and rAML treated and not treated with everolimus. METHODS: Medical charts of adults with TSC-associated rAML followed at a specialty medical center in the Netherlands (1990-2015). Included patients treated with everolimus (n = 33, of which 27 were included in the kidney size analyses and 27 in the kidney function analyses [21 patients in both]; index date = everolimus initiation) and non-treated patients (n = 39, of which 29 were included in the kidney size analyses and 33 in the kidney function analyses [23 patients in both]; index date = one date among all dates with outcome measurement).Percent change in kidney size and kidney function from the index date to the best measurement in the two years post-index date (best response) compared between patients treated and not treated with everolimus. RESULTS: Compared with non-treated patients, significantly more everolimus-treated patients experienced a reduction in the size of their largest kidney in the two years post-index date (85.2% vs. 37.9%, p < 0.01). Also, there was a tendency towards more improvement in the estimated glomerular filtration rate (eGFR) among the everolimus-treated patients (55.6% vs. 33.3%, p = 0.08). CONCLUSIONS: The study results suggest that everolimus is effective in controlling and even reversing the growth of the kidneys, used as a proxy for rAML size, as well as preserving or improving kidney function in patients with TSC and rAML treated in a real-world, observational setting.

Evaluation of ABO blood groups and blood-based biomarkers as a predictor of growth kinetics of renal angiomyolipoma.

PURPOSE: The aim of our study was to investigate the impact of the ABO blood groups and blood-based biomarkers on the growth kinetics of renal angiomyolipoma (AML). METHODS: A total of 124 patients with AML who were followed-up between 2010 and 2018 were retrospectively reviewed. The patients' characteristics were recorded, including age, body mass index (BMI), blood pressure, smoking history, and ABO blood group. Baseline laboratory test results, including serum creatinine, AST, ALT, platelet, neutrophil and lymphocyte count, were used to calculate the estimated glomerular filtration rate (eGFR), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and De Ritis ratio. The Cox regression analysis was used to evaluate the relationship between variables and tumor growth. RESULTS: The study population comprised 71 women and 44 men with a median age of 47.3 (28-65) years. Among patients classified according to the blood groups, no significant differences were observed regarding age, BMI, smoking history, co-morbidities, NLR, PLR, De Ritis ratio, eGFR, or tumor size and localisation. The mean growth rate from baseline to the last scan was 0.36 ± 0.27 cm, 0.21 ± 0.21 cm, 0.14 ± 0.11 cm, and 0.19 ± 0.17 cm for blood type O, A, B, and AB, respectively. In multivariate analysis, eGFR < 60 (p = 0.044), central tumor localisation (p = 0.030), presence of blood group-0 (p = 0.038), and De Ritis ratio ≥ 1.24 (p = 0.047) were statistically associated with tumor growth. CONCLUSION: Our study demonstrates that both the ABO blood groups and the De Ritis ratio might represent independent predictors of tumor growth rate in patients with renal AML.

Trauma-induced adiposis dolorosa (Dercum's disease).

We present a case of a 39-year-old man who presented with chronic bilateral upper extremity pain associated with innumerable angiomyolipomas that developed 5 years after a motor vehicle accident involving his upper extremities. Our case notes the rare nature of painful adipose tissue deposits and the diagnostic challenges.

The impact of renal angiomyolipoma on estimated glomerular filtration rate in patients with tuberous sclerosis complex.

BACKGROUND: There is a growing concern that renal impairment may develop in patients with renal angiomyolipomas (AMLs) associated with tuberous sclerosis complex (TSC) as a consequence of the disease itself and/or the interventions to mitigate the risk of hemorrhage. OBJECTIVE: To assess the estimated glomerular filtration rate (eGFR) in patients with bilateral renal AMLs and the impact of tumor burden and intervention on renal function. DESIGN: Retrospective study. SETTING: Urology department of a tertiary care hospital. PATIENTS AND METHODS: All adult patients (>=18 years of age) with TSC-associated renal AMLs seen from October 1998 to June 2015. We included only patients with bilateral tumors or solitary kidneys at the last follow-up. MAIN OUTCOME MEASURES: The eGFR, renal volume, and number and type of interventions. RESULTS: We identified 12 patients (median age 27.6, interquartile range 23.7-39.9 years), a median follow-up period of 1266 days (33-3133), and a median renal size of 454.7 mL (interquartile range 344.7-1016.9 on the right side; 558.1 mL, interquartile range 253.7-1001.4 on the left). In 11 (91.7%) patients, the eGFR was > 60 mL/min/1.77 m2. Six patients had three total nephrectomies, one had a contralateral partial nephrectomy, and seven had selective arterial embolizations. Intervention was associated with a significantly reduced eGFR. The renal size did not correlate with the eGFR. CONCLUSIONS: TSC-associated renal AMLs may attain a large size but normal renal function is maintained in 92% of patients. Interventions to mitigate the risk of hemorrhage are associated with decreased renal function. LIMITATIONS: The renal size was used as a surrogate for tumor size. Other limitations were the limited number of patients and lack of split renal function testing.

Review of the Tuberous Sclerosis Renal Guidelines from the 2012 Consensus Conference: Current Data and Future Study.

Renal-related disease is the most common cause of tuberous sclerosis complex (TSC)-related death in adults, and renal angiomyolipomas can lead to complications that include chronic kidney disease (CKD) and hemorrhage. International TSC guidelines recommend mammalian target of rapamycin (mTOR) inhibitors as first-line therapy for management of asymptomatic, growing angiomyolipomas >3 cm in diameter. This review discusses data regarding patient outcomes that were used to develop current guidelines for embolization of renal angiomyolipomas and presents recent data on 2 available mTOR inhibitors - sirolimus and everolimus - in the treatment of angiomyolipoma. TSC-associated renal angiomyolipomas can recur after embolization. Both sirolimus and everolimus have shown effectiveness in reduction of angiomyolipoma volume, with an acceptable safety profile that includes preservation of renal function with long-term therapy. The authors propose a hypothesis for mTORC1 haploinsufficiency as an additional mechanism for CKD and propose that preventive therapy with mTOR inhibitors might have a role in reducing the number of angiomyolipoma-related deaths. Because mTOR inhibitors target the underlying pathophysiology of TSC, patients might benefit from treatment of multiple manifestations with one systemic therapy. Based on recent evidence, new guidelines should be considered that support the earlier initiation of mTOR inhibitor therapy for the management of renal angiomyolipomas to prevent future serious complications, rather than try to rescue patients after the complications have occurred.

A case of renal cell carcinoma and angiomyolipoma in an adolescent girl.

We describe a case of renal cell carcinoma in the right kidney together with an angiomyolipoma in the left kidney, encountered in an adolescent girl at Potchefstroom Provincial Hospital, North West Province, South Africa.

Rheb/mTOR/p70s6k Cascade and TFE3 Expression in Conventional and Sclerosing PEComas of the Urinary Tract.

Perivascular epithelioid cell tumors (PEComas) are rarely found in the urinary tract. The clinicopathologic characteristics of 10 cases, retrospectively collected from 5 medical institutions in 3 different European countries, are presented in this study. Male/female ratio was 3:7 and the average age at diagnosis was 62.7 years. Nine cases were sporadic and 1 showed germline mutation of the TSC2 gene. Eight cases were located in the kidney, 1 in the left adrenal and 1 in the right ureter. All of the patients were alive and free of disease at the time of last contact (mean follow-up, 14.1 mo). Four cases displayed a conventional morphology and 6 showed a prominent sclerotic stroma. By immunohistochemistry, melanocytic markers were consistently expressed, especially HMB-45 (10 cases), MiTF (9 cases), and Melan-A (6 cases). Desmin was expressed in 6 cases; 2 cases were positive for CD117; a single case showed TFE3 expression. pMAPK, mTOR, and pAKT demonstrated variable immunostaining with focal positivity in 7, 4, and 2 cases, respectively. Cytokeratins were repeatedly negative in all cases. PEComas in the urinary tract, especially in the renal region, may show a relatively high frequency of the sclerosing histologic subtype. Knowledge of the distinct histology and immunohistochemical profile is vital to correctly diagnose this rare entity.

Differentiation of Sporadic Versus Tuberous Sclerosis Complex-Associated Angiomyolipoma.

OBJECTIVE: We review the imaging of renal angiomyolipomas, including differentiation of tuberous sclerosis complex (TSC)-associated and sporadic renal angiomyolipomas and other solid renal tumors. We also focus on radiologic interventions and molecular targeting of the TSC genetic pathway. CONCLUSION: Imaging plays a central role in the diagnosis and management of renal angiomyolipomas. It provides essential information to make the best therapeutic decisions about the interventional and pharmacologic options to help prevent bleeding and preserve functional parenchyma.

Natural history of angiomyolipoma in lymphangioleiomyomatosis: implications for screening and surveillance.

BACKGROUND: LAM is a rare disease of women categorised by lung cysts and lymphatic abnormalities. The disease occurs sporadically or associated with Tuberous Sclerosis Complex (TSC-LAM). Angiomyolipoma, a benign tumour, prone to haemorrhage, occurs mostly in the kidneys in many of these patients. Treatment guidelines exist for angiomyolipoma in patients with TSC but the natural history of angiomyolipoma in sporadic LAM has not been studied. AIMS: To document the natural history of angiomyolipoma in a national cohort of patients with sporadic LAM to inform tumour screening and surveillance protocols. METHODS: Demographic data, clinical features, lung function and tumour size were obtained from clinical records of patients attending the National Centre for LAM in Nottingham, UK. RESULTS: 122 patients with definite or probable LAM by European Respiratory Society criteria were identified. One hundred and seven had sporadic LAM, of which 53 (50%) had at least one angiomyolipoma. In patients with sporadic LAM presentation of angiomyolipoma preceded or followed onset of lung symptoms by up to 11 and 38 years respectively. Mean tumour size was 28 mm (range 5-140 mm) at presentation and growth was 1.8 mm/yr (95% C.I. 0.42-3.82) thereafter. Eleven patients with sporadic LAM had had a nephrectomy due to angiomyolipoma bleeding. The need for intervention did not differ between those with TSC-LAM and sporadic LAM. CONCLUSIONS: Patients with LAM have a high prevalence of symptomatic angiomyolipoma which can present at any time. Angiomyolipoma in sporadic-LAM have a similar risk of bleeding to those with TSC. All patients should be screened for angiomyolipoma at diagnosis of lung disease by MRI scanning and the tumours require continuous monitoring.

Evidence for pericyte origin of TSC-associated renal angiomyolipomas and implications for angiotensin receptor inhibition therapy.

Nearly all patients with tuberous sclerosis complex (TSC) develop renal angiomyolipomas, although the tumor cell of origin is unknown. We observed decreased renal angiomyolipoma development in patients with TSC2- polycystic kidney disease 1 deletion syndrome and hypertension that were treated from an early age with angiotensin-converting enzyme inhibitors or angiotensin receptor blockers compared with patients who did not receive this therapy. TSC-associated renal angiomyolipomas expressed ANG II type 1 receptors, platelet-derived growth factor receptor-ß, desmin, α-smooth muscle actin, and VEGF receptor 2 but did not express the adipocyte marker S100 or the endothelial marker CD31. Sera of TSC patients exhibited increased vascular mural cell-secreted peptides, such as VEGF-A, VEGF-D, soluble VEGF receptor 2, and collagen type IV. These findings suggest that angiomyolipomas may arise from renal pericytes. ANG II treatment of angiomyolipoma cells in vitro resulted in an exaggerated intracellular Ca(2+) response and increased proliferation, which were blocked by the ANG II type 2 receptor antagonist valsartan. Blockade of ANG II signaling may have preventative therapeutic potential for angiomyolipomas.

The ominous sequence in patients with tuberous sclerosis complex.

BACKGROUND: The clinical phenotypes and their severity in patients with tuberous sclerosis complex can be quite variable and are sometimes never determined simply by the primary mutation. These make clinically selecting appropriate treatments and predicting disease outcome difficult. In this report, the prognostic ominous sequence was evaluated in association with clinical manifestations and gene mutations. METHODS: The patients were classified by each renal lesion of angiomyolipomas and polycystic disease. The other clinical manifestations and outcomes of epilepsy, mental retardation, facial angiofibromas, subependymal giant cell astrocytoma, cortical tubers were reviewed and each gene mutations were analyzed in seven unrelated patients. RESULTS: Two patients with multiple and large proliferative renal angiomyolipoma showed poor clinical outcome than the patients with other renal lesions. These patients presented with progressively proliferative facial angiofibroma, West syndrome, Lennox-Gastaut syndrome, severe mental retardation, subependymal giant cell astrocytoma and they were affected by TSC2 gene mutations. CONCLUSION: The sequence of progressively proliferative renal angiomyolipoma, facial angiofibroma, West syndrome and TSC2 gene mutations might be prognostic ominous factors.

Radiofrequency ablation of incidental benign small renal mass: outcomes and follow-up protocol.

OBJECTIVE: To review our 10-year experience with radiofrequency ablation, focusing on the outcomes for the incidental benign renal tumor. Tumor ablation is an alternative minimally invasive approach for the treatment of small renal masses (SRMs), with published series appropriately emphasizing the outcomes for the renal cell carcinoma subset of treated tumors. However, just as with partial nephrectomy, approximately 20% of SRMs are benign. The intermediate- to long-term outcome of the incidentally ablated benign tumor and its appropriate follow-up protocol is unknown. METHODS: All SRMs treated with temperature-based radiofrequency ablation from 2001 to 2011 were reviewed. Of a total of 280 enhancing SRMs biopsied at radiofrequency ablation, 47 were confirmed as benign tumors. Ablation success was defined as the lack of enhancement on the initial postablation axial imaging. Recurrence was defined as tumor growth and enhancement on follow-up axial imaging. RESULTS: Of the 47 benign tumors, 32 were treated percutaneously and 15 laparoscopically. The histologic biopsy finding was angiomyolipoma in 10 and oncocytoma in 37. The median tumor size was 2 cm (range 1-3.6), and the mean follow-up was 45 months. No recurrences developed, and all lesions required only 1 treatment session. The median pre- and postoperative glomerular filtration rate was 77 mL/min/1.73 m(2) (range 39-137) and 68 mL/min/1.73 m(2) (range 36-137). The present study was limited by its retrospective nature and small sample population. CONCLUSION: Radiofrequency ablation of SRMs <3.5 cm found to be benign on concurrent biopsy can be efficaciously treated with a single treatment session. Long-term follow-up imaging might not be required if successful ablation is determined at the initial post-treatment cross-sectional imaging study.

Changes in lung function and chylous effusions in patients with lymphangioleiomyomatosis treated with sirolimus.

BACKGROUND: Lymphangioleiomyomatosis (LAM) is a disorder that affects women and is characterized by cystic lung destruction, chylous effusions, lymphangioleiomyomas, and angiomyolipomas. It is caused by proliferation of abnormal smooth muscle-like cells. Sirolimus is a mammalian target of rapamycin inhibitor that has been reported to decrease the size of neoplastic growths in animal models of tuberous sclerosis complex and to reduce the size of angiomyolipomas and stabilize lung function in humans. OBJECTIVE: To assess whether sirolimus therapy is associated with improvement in lung function and a decrease in the size of chylous effusions and lymphangioleiomyomas in patients with LAM. DESIGN: Observational study. SETTING: The National Institutes of Health Clinical Center. PATIENTS: 19 patients with rapidly progressing LAM or chylous effusions. INTERVENTION: Treatment with sirolimus. MEASUREMENTS: Lung function and the size of chylous effusions and lymphangioleiomyomas before and during sirolimus therapy. RESULTS: Over a mean of 2.5 years before beginning sirolimus therapy, the mean (±SE) FEV1 decreased by 2.8%±0.8% predicted and diffusing capacity of the lung for carbon monoxide (Dlco) decreased by 4.8%±0.9% predicted per year. In contrast, over a mean of 2.6 years of sirolimus therapy, the mean (±SE) FEV1 increased by 1.8%±0.5% predicted and Dlco increased by 0.8%±0.5% predicted per year (P<0.001). After beginning sirolimus therapy, 12 patients with chylous effusions and 11 patients with lymphangioleiomyomas experienced almost complete resolution of these conditions. In 2 of the 12 patients, sirolimus therapy enabled discontinuation of pleural fluid drainage. LIMITATIONS: This was an observational study. The resolution of effusions may have affected improvements in lung function. CONCLUSION: Sirolimus therapy is associated with improvement or stabilization of lung function and reduction in the size of chylous effusions and lymphangioleiomyomas in patients with LAM. PRIMARY FUNDING SOURCE: Intramural Research Program, National Heart, Lung, and Blood Institute, National Institutes of Health.

[Rupture of renal angiomyolipoma during pregnancy: a case report].

A 39-year-old woman, who was followed because of a 4 cm asymptomatic angiomyolipoma (AML) in the left kidney, presented with an acute onset of lower left back pain in the 38th week of her first pregnancy. An ultrasound revealed an 8 cm mass suggestive of AML rupture and retroperitoneal hemorrhage. An emergency caesarean delivery was performed. A post-delivery computed tomographic scan confirmed the AML rupture and selective embolization was performed. This was a case in which the AML grew rapidly during the pregnancy ; therefore, we discuss the relationship between AML and pregnancy.

[Renal epithelioid angiomyolipoma]. / Angiomyolipome épithélioïde rénal.

Renal epithelioid angiomyolipomas (ReAML) are rare tumors (identified in less than 0,1 per thousand in general population) and represent 8% of operated angiomolipomas (AML). The diagnostic is histological, with an epithelioid cell component among the typical AML cells. ReAML are tumors derived from perivascular epithelioid cells (PEComa). There are benign PEComas, potentially aggressive PEComas and malignant PEComas. Most malignant PEComas are ReAML. There are two ReAML clinical entities, sporadic or associated to Tuberous Sclerosis Complex (TSC). ReAML are unique, localized and sporadic solid tumors of the kidney of variable size that can be revealed as classical AML with local symptoms or a complication (hemorrhage). Revelation mode is mostly radiologic. ReAML are fat-poor on CT-scan. They can be misdiagnosed with renal cell carcinoma (RCC). (One third of ReAML are malignant with a locoregional, nodal or metastatic evolution that can lead to death. ReAML treatments are multimodal depending of histology, clinical-radiological entity, evolution and the patient. Partial nephrectomy or follow-up are the benign entity treatment. Radical nephrectomy eventually followed by doxorubicine or rapamycine treatments are recommended for potentially aggressive and malignant entities.

Evaluation of renal function of angiomyolipoma patients after selective transcatheter arterial embolization.

BACKGROUND: Angiomyolipoma patients may have renal insufficiency before selective transcatheter arterial embolization (TAE) or may undergo subsequent surgery after TAE. Therefore, this retrospective study examined our experience with TAE or TAE and subsequent surgery on renal function of angiomyolipoma patients with and without preexisting renal insufficiency. METHODS: 25 patients who had undergone TAE for renal angiomyolipoma over a 7-year period were reviewed. The 25 patients were grouped according to whether or not they had undergone further surgery. Preexisting renal insufficiency was compared between the 2 groups. The TAE and surgery group was further subdivided into 2 subgroups according to total nephrectomy or not. The TAE-alone group was further subdivided into 2 subgroups by presence of preexisting renal insufficiency or not. In each group and subgroup, pre-TAE and post-TAE renal function, including serum creatinine and creatinine clearance were compared. RESULTS: TAE rather than TAE and surgery was more likely chosen in the presence of preexisting renal insufficiency (6/13 versus 1/12, P=0.035). In TAE-alone patients, no statistical differences were noted between serum creatinine and creatinine clearance before and after TAE. Conversely, TAE and surgery patients who had undergone total nephrectomy rather than nephron-sparing surgery differed significantly in preand post-TAE serum creatinine (0.77 versus 1.07, P=0.014) and creatinine clearance (98.1 versus 70.7, P=0.032). CONCLUSIONS: This study demonstrated that TAE alone for treating renal angiomyolipomas was able to preserve renal function, despite the presence of mild preexisting renal insufficiency. Conversely, surgery after TAE, particularly total nephrectomy, should be avoided whenever possible.

Analysis of the oestrogen response in an angiomyolipoma derived xenograft model.

Angiomyolipomas are benign mesenchymal tumours of smooth muscle, blood vessels and fat which occur sporadically or associated with tuberous sclerosis and lymphangioleiomyomatosis (LAM), a rare cystic lung disease. Angiomyolipoma and LAM are caused by loss of function of either the tuberous sclerosis-1 or -2 genes resulting in activation of p70S6kinase (S6K1) and uncontrolled cellular proliferation. LAM and angiomyolipoma can be exacerbated by oestrogens but how this occurs is not understood. To address this question, we created a xenograft tumour system in nude mice using immortalised angiomyolipoma cells. Angiomyolipoma xenografts had active S6K1, p38, p42/44 MAPK and Akt; they grew more rapidly and had greater Akt phosphorylation after oestrogen treatment of tumour-bearing mice. Transcriptional profiling showed oestrogen induced 300 genes including extracellular matrix proteins, proteases, cell cycle regulatory proteins and growth factors including platelet derived growth factor-C (PDGF-C). Biologically active PDGF-C was produced by primary angiomyolipoma cells in culture and PDGF-C protein was present in the neoplastic smooth muscle cells of 5/5 human angiomyolipoma and 4/5 LAM tissues examined by immunohistochemistry. These findings suggest that the response to oestrogen in this model is mediated by activation of Akt and transcriptional events. This model may prove useful for studying the biology and effect of drugs on angiomyolipoma and diseases related to TSC.

Tumor capacitance: electrical measurements of renal neoplasia.

PURPOSE: Studies have demonstrated that biological tissues possess unique electrical properties. We evaluate the electrical properties of renal tumors using a specialized probe with the capability of measuring intra-tissue capacitance in an ex vivo model of fresh surgically excised tissue. MATERIALS AND METHODS: An electrical monitoring device was used to measure tissue capacitance at a frequency of 1 MHz on 34 ex vivo kidney specimens freshly obtained after surgical excision. Tissue capacitance was promptly measured in the excised tumor as well as surrounding normal parenchyma and fat. Dielectric permittivity in each tissue was calculated using the measured capacitance data. These data were compared and correlated to pathological findings. RESULTS: The final pathology on the 34 specimens revealed 28 renal cell carcinomas (RCC), 3 oncocytomas and 3 angiomyolipomas. In patients with RCC dielectric permittivity of tumor tissue was 1.43 +/- 0.39 times greater than that of surrounding normal parenchyma (p < 0.001). The average tumor-to-normal tissue dielectric permittivity ratio for RCC was significantly greater than that for angiomyolipoma (1.43 +/- 0.39 vs 0.73 +/- 0.77, p < 0.05) but similar to that for oncocytoma (1.43 +/- 0.39 vs 1.63 +/- 0.77, p = 0.39). CONCLUSIONS: Tissue capacitance measurements may be used to differentiate renal tumor from surrounding normal tissue. In vivo studies will ultimately determine the clinical use of this technology in localizing renal neoplasms and differentiating between malignant and benign tissues.