Management of Nontraumatic Spontaneous Renal Hemorrhage (Wünderlich Syndrome) through Robotic-Assisted Laparoscopic Nephrectomy: A Case Series

BACKGROUND Wünderlich syndrome (WS) is a rare diagnosis of nontraumatic spontaneous renal hemorrhage into the subcapsular, perirenal, or pararenal spaces. Prompt and effective intervention is necessary for an accurate pathological diagnosis and preservation of life. In the current literature, open surgery is the primary option when conservative treatment fails, but there can be serious trauma and corresponding consequences. Herein, we present 3 cases of Wünderlich syndrome managed by robot-assisted laparoscopic nephrectomy via a retroperitoneal approach. CASE REPORT Patient 1 was a 44-year-old woman with right flank pain for 6 h. Patient 2 was a 53-year-old woman with a history of diabetes who had pain in her right flank pain and nausea for 1 day. Patient 3 was a 45-year-old man with left flank pain for 1 day. All cases of WS were confirmed by CT. All 3 patients were treated with retroperitoneal robot-assisted nephrectomy after conservative treatment failed. Pathological examination confirmed that patient 1 had angiomyolipoma, and patients 2 and 3 had renal clear cell carcinoma. At the 9-month follow-up, renal function was good and no evidence of recurrence or metastasis has been detected. CONCLUSIONS These cases have highlighted the importance of the clinical history and imaging findings in the diagnosis of Wünderlich syndrome, and show that rapid management can be achieved using robot-assisted laparoscopic nephrectomy. However, it is crucial to have a skilled surgical team and adequate preoperative preparation.

[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.

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.

Hybrid Management of a Wünderlich's Syndrome Secondary to a Giant Ruptured Renal Angiomyolipoma: A Case Report

Wünderlich's syndrome, a rare and life-threatening condition involving spontaneous renal hemorrhage, is commonly associated with renal angiomyolipoma (rAML). Management options for rAML include surveillance, mTOR inhibitors, selective arterial embolization (SAE), and surgery. When complicated by Wünderlich's syndrome, prompt and adequate interventional treatment is necessary to prevent fatal outcomes. We present a unique case of a young female patient with Tuberous Sclerosis Complex who experienced a massive ruptured rAML, leading to Wünderlich's syndrome. Our approach involved a multidisciplinary hybrid strategy, combining SAE and nephrectomy, highlighting SAE's valuable role even when radical treatment is required.

The association between computed tomography attenuation value of renal angiomyolipoma associated with tuberous sclerosis complex and response to everolimus

BACKGROUND

The response to everolimus in patients with renal angiomyolipoma associated with tuberous sclerosis complex (TSC-RAML) varies among individuals. This study aims to identify potential factors associated with the response to everolimus.

METHOD

We retrospectively examined data encompassing age, gender, tumor size, computed tomography attenuation value (CT value), CT enhancement, and tumor reduction rate in patients with TSC-RAML undergoing everolimus in two previously registered clinical trials.

RESULT

A total of 33 participants (29.33 ± 6.63 years old, 20 females) were included. The correlation analysis conducted separately for tumors located in the left and right kidneys revealed significant negative correlations (P < 0.05) between tumor reduction rate and age, as well as tumor size. While significant positive correlations (P < 0.05) were observed between tumor reduction rate and unenhanced CT value as well as CT enhancement. Nonetheless, based on multiple linear regression analysis, unenhanced CT value emerged as the sole-independent predictor of tumor reduction rate among age, gender, tumor size, unenhanced CT value and CT enhancement for both left (coefficient = 0.00319, P < 0.0001) and right kidneys (coefficient = 0.00315, P = 0.0104). Notable reductions were observed in unenhanced CT value (- 3.81 vs - 24.70HU, P < 0.0001) and CT enhancement (48.16 vs 33.56HU, P < 0.0001) following a 3-month administration of everolimus. The decline in both unenhanced CT value and tumor size predominantly occurred within the initial 3 months, subsequently maintaining a relatively stable level throughout the treatment.

CONCLUSION

The unenhanced CT value of TSC-RAML showed an independent correlation with the response to everolimus, suggesting its potential as a predictor of everolimus efficacy in patients with TSC-RAML.

Rupture of Renal Angiomyolipoma Post Fibrinolysis: A rare complication of fibrinolytic therapy

Angiomyolipoma is a common benign solid tumour that accounts for up to 3% of all renal tumours; most of the cases are sporadic. However, it can be part of other diseases. Angiomyolipomas are usually found incidentally through unrelated clinically indicated images but also, they can be diagnosed after complications have occurred. We report the case of retroperitoneal haemorrhage following the rupture of renal angiomyolipoma post-fibrinolysis, we are highlighting such a rare condition, the management options and the follow-up plan. The management of angiomyolipomas ranges from conservative treatment to surgical intervention depending on the patient's condition and the tumour's radiological features. Following-up on patients with angiomyolipomas depends on the symptoms and the tumour size. Till date, there is no reported cases of renal angiomyolipoma rupture post-fibrinolysis therapy as a treatment for myocardial infarction in non-percutaneous intervention capable facility.

Clinical Practice Guidelines for tuberous sclerosis complex-associated renal angiomyolipoma by the Japanese Urological Association: Summary of the update

New clinical issues have been raised through an interval of 7 years from the previous version (2016). In this study, we update the "Clinical Practice Guidelines for tuberous sclerosis complex-associated renal angiomyolipoma" as a 2023 version under guidance by the Japanese Urological Association. The present guidelines were cooperatively prepared by the Japanese Urological Association and Japanese Society of Tuberous Sclerosis Complex; committee members belonging to one of the two societies or specializing in the treatment of this disease were selected to prepare the guidelines in accordance with the "Guidance for preparing treatment guidelines" published by Minds (2020 version). The "Introduction" consisted of four sections, "Background Questions (BQ)" consisted of four sections, "Clinical Questions (CQ)" consisted of three sections, and "Future Questions (FQ)" consisted of three sections (total: 14 sections). Concerning CQ, an agreement was confirmed through voting by the committee members based on the direction and strength of recommendation, accuracy of evidence, and recommendation comments. The present guidelines were updated based on the current evidence. We hope that the guidelines will provide guiding principles for the treatment of tuberous sclerosis complex-associated renal angiomyolipoma to many urologists, becoming a foundation for subsequent updating.

Adverse Events of Everolimus in Patients with Tuberous Sclerosis Complex Treated for Renal Angiomyolipoma/Subependymal Giant Cell Astrocytoma

Background: Although regarded as a potentially efficient approach to address tuberous sclerosis complex (TSC)-associated complications, the adverse event profile of everolimus has not yet been fully elucidated. The present study aimed to clarify the adverse event spectrum in patients with TSC who are using everolimus for common indications, in comparison to those who do not use everolimus. Materials and Methods: We recruited patients with TSC who were followed up annually at TSC integrated clinics or referred for medical assistance. Medical reviews and laboratory investigations were performed at baseline and annually by clinical physicians. The adverse events were assessed as per the National Cancer Institute Common Terminology Criteria for Adverse Events. Results: Common adverse events in everolimus users included hypercholesterolemia (55%), gingivostomatitis (50%), proteinuria (50%), and hyperglycemia (40%). Compared with everolimus nonusers, the occurrence of gingivostomatitis and proteinuria was significantly higher in everolimus users (gingivostomatitis, p=0.02; proteinuria, p=0.02). Among the everolimus users, 12 patients had level I CTCAE, and five had level II CTCAE. None of the everolimus users presented with CTCAE level III or higher. Conclusion: Patients with TSC who are everolimus users had a higher tendency to develop gingivostomatitis and proteinuria compared to nonusers. However, no differences were observed in the occurrence of other adverse events between everolimus users and nonusers.

Renal angiomyolipoma with tumor thrombi: Clinical analysis of 18 cases in a single-center experience

PURPOSE

To improve understanding of the clinical features of renal angiomyolipoma (AML) accompanied by tumor thrombus (TT).

METHODS

From January 2017 to February 2022, 18 patients with AML and TT were enrolled. We retrospectively analyzed them and there were 6 cases of epithelial AML (EAML) and 12 of classical AML (CAML). We compared the key variables between the two cohorts.

RESULTS

The mean age of the 18 cases was 42.0 (standard deviation [SD] 13.4) years and 14 (77.8%) were female. Eleven (61.1%) tumors were on the right side. Only two (11.1%) cases presented with flank pain. The mean follow-up time was 33.6 (IQR: 20.1-48.5) months. All participants were alive at the end of follow-up. One case developed lung metastases 21 months after operation but entered remission after 2 years of everolimus treatment. The imaging diagnoses of all CAML cases were consistent with the pathology, while all imaged EAML cases were diagnosed with carcinomas. Five EAML cases, but only one CAML case, exhibited necrosis (83.3 vs. 8.3%, P = 0.001). The Ki-67 index of the EAML group was significantly higher than that of the CAML group (7 vs. 2, P = 0.004).

CONCLUSIONS

Compared to CAML, EAML tended to be associated with a higher imaging misdiagnosis rate, and was more commonly associated with necrosis and a higher Ki-67 index. Surgery remains the prime treatment for nonmetastatic AML with TT; such cases have a relatively good prognosis despite the malignant potential.

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.

Renal Lipoma-Like Angiomyolipoma of Tumour Thrombus Extending to the Confluence of Inferior Vena Cava with Right Atrium: A Rare Case Report and Literature Review

Angiomyolipoma (AML) complicated with tumour thrombus extending to the confluence of inferior vena cava (IVC) with right atrium is rarely observed. We report a female AML patient admitted to our centre on January 21, 2020, with complication of tumour thrombus extending to the confluence of IVC with right atrium and had no sign of difficult breathing. She underwent whole-abdominal enhanced CT for abdominal pain and was diagnosed with a possible renal AML with tumour thrombus. Open radical nephrectomy and thrombectomy of vena cava were performed. Intraoperative transoesophageal echocardiography indicated that the tumour thrombus has reached the confluence of IVC with right atrium. The operation took 255 min with an intraoperative haemorrhage of 800mL. The patient was discharged 7 days after surgery. Pathology revealed lipoma-like AML. Immunohistochemistry showed vimentin (+), EMA (-), HMB45 (+), S-100 (-), SMA (+), TFE-3 (-), melan A (+). After 2 years of follow-up, we found that the patient showed full recovery and had no recurrence. Therefore, lipoma-like AML should also be followed closely for recurrence and metastasis. When AML involves IVC tumour thrombus, open thrombectomy and radical nephrectomy are safe and effective methods.

Clinical features and outcomes of male patients with lymphangioleiomyomatosis: A review

BACKGROUND

Lymphangioleiomyomatosis (LAM) is a rare disease involving multiple systems, which is divided into sporadic LAM (S-LAM) and tuberous sclerosis complex-LAM, mostly affecting women who are in childbearing age stage. Data on male patients are limited and scattered. Therefore, it is necessary to conduct a systematic review to investigate the clinical features, diagnosis, treatment, and outcomes of LAM in male.

METHODS

We performed a literature review by searching for all the published reported cases of LAM in male during the past 35 years (April 1986-October 2021).

RESULTS

36 male patients described in 26 references were included in this article. The median age of onset was 34 years (interquartile range: 1-79). The most common initial manifestations were cough, dyspnea, respite, and hemoptysis, with pulmonary complications such as pneumothorax and chylothorax. Five patients (13.9%) were asymptomatic at admission. Nearly half of the 36 male patients had thin-walled air-filled cysts that were visible throughout both lungs. Considering the abovementioned atypical clinical features, misdiagnosis was committed in 8 patients (22.2%). In addition, patients with tuberous sclerosis complex lymphangioleiomyomatosis often have no pulmonary manifestations at onset but present multiple extrapulmonary manifestations and have higher rates of renal angiomyolipomas than patients with S-LAM (P < 0.01). Eventually, 4 patients with S-LAM eventually died.

CONCLUSION

Physicians should increase the awareness of LAM in male. Early monitoring of various systems should be recommended to ensure early management and active follow-up. Tuberous sclerosis complex patients should immediately be tracked for the onset of LAM disease to improve prognosis.

Renal angiomyolipoma with inferior vena cava and right atrial embolism: A case report and literature review

Renal angiomyolipoma (AML) with renal vein, inferior vena cava (IVC), and right atrial embolism is a rare solid tumor, whose etiology and pathogenesis are still unclear. Moreover, it is often misdiagnosed. One patient with renal AML complicated with renal vein, IVC, and right atrial embolism was admitted to the Second Xiangya Hospital of Central South University, who was a 35-year-old female, without any previous medical history, presented with right low back pain for more than 3 years. Computed tomography (CT) scan showed irregular lobulated fatty density mass in the right kidney, renal vein, IVC, and right atrium. The contrast-enhanced scan showed no enhancement of fat components at each phase and mild enhancement of solid components. Radical resection of the right kidney and removal of tumor thrombus were performed, and there was no recurrence 1 year after the operation. It is rare for renal AML to grow along the renal vein, IVC, and extend to the right atrium. Imaging examination is extremely important, and the CT findings of this case are characteristic, but the diagnosis eventually depends on pathological and immunohistochemical examinations.

Pulmonary lymphangioleiomyomatosis and renal angiomyolipoma in a patient with systemic lupus erythematosus: A case report

BACKGROUND

The co-incidence of systemic lupus erythematosus (SLE) and tuberous sclerosis with pulmonary lymphangioleiomyomatosis (LAM) and renal angiomyolipoma (AML) is rare. In such patients, the rupture of renal AML may result in fatal circumstances, but this may be preventable.

METHODS

A 22-year-old Asian woman with SLE was admitted to our hospital with severe left-flank pain. Imaging studies showed the bilateral rupture of multiple renal AMLs.

RESULTS

The patient underwent emergency selective transcatheter embolization (TE) of the left renal artery. After TE and massive hydration, the patient complained of dyspnea and postembolization syndrome with fever. The chest computed tomography (CT) revealed pulmonary LAM, pulmonary edema with bilateral pleural effusions, and pneumonic consolidation. After the emergency procedure, the patient was treated with intravenous administration of antibiotics, diuretics, and nonsteroidal anti-inflammatory drugs for 10 days. The patient recovered favorably and was discharged 20 days after the treatment. She was diagnosed with renal AML and pulmonary LAM along with facial angiofibromas as well as tuberous sclerosis complex (TSC), although she had no TSC1 or TSC2 gene mutations.

CONCLUSION

Although rare, SLE may coexist with TSC, along with LAM and AML, with a risk of AML rupture. The activation of the mTOR signaling pathway is shared between SLE and TSC. Thus, in patients with SLE, clinicians should consider imaging studies, such as kidney sonography and chest CT, to screen for possible manifestation of AML and LAM.

Tuberous sclerosis complex with skin lesions as the initial presentation: A case report and multidisciplinary discussion

We reported a case of tuberous sclerosis complex with facial angiofibroma as the initial presentation and conducted a multidisciplinary discussion. The patient, a young female, was admitted to the Department of Dermatology for cosmetic purpose. After the examination, she was found to have multiple system involvement, including a large renal angiomyolipoma pressing on the liver. She never had any subjective symptom. After consultation by the multidisciplinary team of tuberous sclerosis complex, the patient was treated with everolimus orally and followed up regularly. It is suggested that dermatologists should pay attention to the systemic involvement of patients with tuberous sclerosis complex. Early intervention can prolong the life of patients and improve their life quality. Multidisciplinary collaboration for lifelong disease management is the key to enhance the diagnosis and treatment for tuberous sclerosis complex and enhance the prognosis of patients.

Mechanistic Target of Rapamycin (mTOR) Inhibitors

Mechanistic target of rapamycin (mTOR) inhibitors are macrocyclic lactone antibiotics derived from Streptomyces hygroscopicus that prevent T lymphocyte activation and B cell differentiation. Unlike calcineurin inhibitors (CNIs) that inhibit cytokine production, mTOR inhibitors block the cytokine signal transduction to arrest cells in the G1 to S phase. This class of drugs is commonly used for post-transplantation and cancer management because of its immunosuppressive and antiproliferative properties, respectively. The potential uses of mTOR inhibitors are heavily explored because of their impact on cell growth and proliferation. However, mTOR inhibitors have a broad range of effects that can result in adverse reactions, but side effects can occur with other immunosuppressive agents as well. Thus, the performance of mTOR inhibitors is compared to the outcomes and adverse effects of other immunosuppressive drugs or the combination of other immunosuppressants and mTOR inhibitors. Because mTOR regulates many downstream pathways, mTOR inhibitors can affect these pathways to manage various diseases. Sirolimus (rapamycin) is approved by the Food and Drug Administration (FDA) to treat post-renal transplantation and lymphangioleiomyomatosis (LAM). Everolimus is approved by the FDA to treat postmenopausal advanced hormone receptor-positive, HER2-negative breast cancer in women, progressive neuroendocrine tumors of pancreatic origin (PNET), advanced renal cell carcinoma (RCC), renal angiomyolipoma (AML) and tuberous sclerosis complex (TSC), and subependymal giant cell astrocytoma (SEGA) associated with TSC as well as renal and liver transplantation. Temsirolimus is approved by the FDA to treat advanced RCC. Opportunities to use mTOR inhibitors as therapy for other transplantation, metabolic disease, and cancer management are being researched. mTOR inhibitors are often called proliferation signal inhibitors (PSIs) because of their effects on proliferation pathways.

Right renal angiomyolipoma with intracardiac extension and pulmonary embolism

Angiomyolipoma is the most common benign mesenchymal neoplasm of the kidney. Despite its benign nature, it may, in rare instances, invade the inferior vena cava and right cardiac chambers. A tumor thrombus in the pulmonary artery is an extremely rare but potentially fatal complication. We report a rare case of 53-year-old woman showing a right renal angiomyolipoma with intracardiac extension and pulmonary embolism. The patient underwent open radical right nephrectomy and thrombectomy of the inferior vena cava and pulmonary artery. Our case highlights that close attention to these complications is important to determine the surgical plan.

Efficacy and safety of low-dose everolimus treatment for renal angiomyolipoma associated with tuberous sclerosis complex

BACKGROUND

The aim of this study was to evaluate the safety and efficacy of low-dose everolimus treatment in patients with tuberous sclerosis complex (TSC)-associated angiomyolipoma (AML) with renal dysfunction or low body weight.

METHODS

We investigated a total of 50 adult patients underwent everolimus treatment for AML associated with TSC. For patients with renal dysfunction (serum creatinine level ≥ 1.5 mg/dl) or low body weight (body weight < 35 kg), 5 mg of everolimus was administered daily (low-dose group). For patients without renal dysfunction or low body weight, 10 mg of everolimus was administered daily (conventional-dose group). The treatment effects and adverse events were compared between the two groups.

RESULTS

There were 20 patients in the low-dose group, and 30 in the conventional-dose group. The average reduction rate of the AML volume in the low-dose group was 52%, whereas it was 60% in the conventional-dose group. No significant differences were found in the average reduction rate between the groups (P = 0.24). The average blood everolimus trough levels were 7.7 ± 3.1 ng/mL in the low-dose group and 12.2 ± 5.7 ng/mL in the conventional-dose group. The level was significantly higher in the conventional-dose group than in the low-dose group (P = 0.004). The incidences of stomatitis and irregular menstruation were significantly lower in the low-dose group than in the conventional-dose group (P = 0.009, P = 0.045, respectively).

CONCLUSIONS

The present study demonstrates that low-dose everolimus treatment is safe and effective for TSC-associated AML. This treatment was well tolerated and adverse events were mild in all cases.

A scoring system based on clinical features for the prediction of sporadic renal angiomyolipoma rupture and hemorrhage

The purpose of this study is to analyze the risk factors of sporadic renal hamartoma and establish a risk scoring system, and to intervene in patients with high-risk sporadic renal hamartoma who are prone to rupture and bleeding as soon as possible.Retrospective univariate and multivariate logistic analyzes were conducted for clinical data of 332 sporadic renal hamartoma patients to screen out independent risk factors of tumor rupture. Score of each independent risk factor was calculated. (Calculation formula: the risk coefficient of each factor = the beta regression coefficient of each factor/the minimum value of the beta regression coefficient of all factors, the value of the smallest beta regression coefficient corresponding to all the factors was assigned 1 point. The score of each factor was equal to the risk coefficient of each variable was taken as an integer value by rounding.) The total score was equal to the sum of all factors. Then the area under the receiver operating characteristics (AUC) curve was compared between high risk factors and scoring system. Finally, the scoring system was evaluated by the area under the curve (AUC) and the Hosmer-Lemeshow method in an independent cohort of 130 patients.Factors such as symptoms at presentation, tumor size, tumor blood supply, and tumor growth pattern were significant predictors of sporadic renal angiomyolipoma rupture in both the univariate and multivariate analyses; these predictors were included in the scoring system to predict sporadic renal angiomyolipoma rupture. There were no significant differences in AUCs between high risk factors and scoring system (z = 0.6434, P = .583, AUC = 0.913, and 0.903 for high risk factors and scoring system, respectively). The sporadic renal angiomyolipoma patients who scored >6 points were prone to rupture. AUROC of the scoring system in the validation set was 0.854(95%CI:0.779, 0.928). Using the Hosmer-Lemeshow method, the value of X was 2.916, P = .893, suggesting the scoring system fitted well.A scoring system based on clinical features is simple and effective in predicting sporadic angiolipoma rupture and hemorrhage. When the score is higher than 6 points, the probability of hamartoma rupture and hemorrhage is significantly increased and early intervention is needed.

Wunderlichs syndrome in patient with sporadic bilateral angiomyolipomas - case report

We present the case report of bilateral renal angiomyolipomas in a 70-year-old patient. Spontaneous bleeding into the retroperitoneum and hemodynamic instability required an acute surgical revision with a left-sided nephrectomy. The contralateral angiomyolipoma was selectively embolized in the second period and subsequently resected.

[A woman with acute flank pain]

A 55-year-old woman presented at the Emergency Department with flank pain. She was pale, hemodynamically unstable, and had a palpable mass in her right flank. CTA of the abdomen revealed a bleeding from an angiomyolipoma of the right kidney, which was successfully treated by selective coiling of the supplying renal artery.

[Hepatic epithelioid angiomyolipoma/PEComa and focal nodular hyperplasia in a patient with a previous history of cutaneous melanoma]

Hepatic perivascular epithelioid cell tumors (PEComas) are uncommon mesenchymal neoplasms. PEComas concurrent with other hepatic lesions is a very rare occurrence, with only two previously reported cases. We report a primary hepatic PEComa associated with focal nodular hyperplasia in a patient with a previous history of cutaneous melanoma. Diagnostic imaging studies suggested a hepatic adenoma and the patient underwent a segmentectomy. The tumor was mainly composed of epithelioid cells, adipose tissue and smooth muscle fibers intermixed with blood vessels. The neoplastic cells were diffusely immunoreactive for HMB-45, Melan-A and smooth muscle actin, but not for Hepatocyte, S100, MITF or BRAF. Molecular studies were negative for BRAFV600 mutation. The final diagnosis was hepatic epithelioid angiomyolipoma/PEComa. The differential diagnosis of hepatic PEComa is discussed.

Trans-Radial Embolization of Bleeding Renal Angiomyolipoma in Pregnant 30-Year-Old Female - A Case Report

Trans-radial access offers several unique advantages and is being used more frequently for interventional radiology procedures. We report the use of trans-radial arterial access to embolize a large bleeding angiomyolipoma in a 30-year-old pregnant patient presenting in the first trimester. Trans-radial approach was chosen to minimize the effects of radiation on the fetus. Subsequent postprocedural pregnancy course was uneventful with stability of the angiomyolipoma and no further hemorrhage. This case highlights the benefits of trans-radial embolotherapy in gravid patients to reduce the risk of radiation exposure to the fetus.

Retroperitoneal bleeding caused by spontaneus rupture of renal angiomyolipoma following cesarean section treated with selective embolisation

OBJECTIVE

To describe management of a spontaneus rupture of renal angiomyolipoma after cesarean section.

DESIGN

Case report.

SETTING

Department of Gynaecology and Obstetrics, Hospital &#352;ternbek; Department of Obstetrics and Gynaecology, Palacky University and University Hospital, Olomouc.

CASE REPORT

29-year-old patient underwent acute cesarean section at 35 weeks of gestation for pPROM, placenta praevia marginalis, suspicion of placenta accreta by ultrasound and MRI and transverse position of the fetus. The next morning was found out a spontaneus rupture of renal angiomyolipoma causing progressive anemisation. We describe the following management.

CONCLUSION

Incidention of tumors complicating gravidity may occur more often due to changes in population characteristics. Methods of interventional radiology are ordinarily used for severe hemorrage postpartum or for prophylactic occlusion of illiac arteries before cesarean section with morbidly adherent placenta. We show here usage of selective embolisation in not so common obstetrical complications.

Giant renal angiomyolipoma in a solitary kidney

While renal angiomyolipomas (AMLs) generally remain small and asymptomatic, larger AMLs are more common in tuberous sclerosis patients. Giant AMLs over 20 cm are a rare entity and little is known about their management. We present a unique case of a 48-year-old woman with tuberous sclerosis and a 39 cm AML arising from a solitary kidney, after undergoing nephrectomy for a prior AML. Giant renal AMLs can occur in patients with tuberous sclerosis and resection should be considered even for large tumors. Renal sparing is often difficult and patients should be counseled about potential need for postoperative hemodialysis.

Large Aneurysm in Renal Angiomyolipoma

Large aneurysms seen in renal angiomyolipoma are usually more common in patients with tuberous sclerosis in comparison with sporadic cases and they are more prone to hemorrhage ranging from renal hematoma to life-threatening perirenal hemorrhages. We present a case of 13-year female patient who was referred to Civil Hospital, Karachi, with bilateral flank pain, cutaneous nodule and low intelligence. Her color doppler ultrasound revealed pseudoaneurysm in left kidney on the background of bilateral renal angiomyolipomas. Contrast enhanced CT scan confirmed various radiological manifestations of tuberous sclerosis including subependymal tubers, bilateral angiomyolipomas, and pseudoaneurysm associated with perinephric hemorrhage in left kidney.

Epithelioid Angiomyolipoma: A Case Report

Epithelioid angiomyolipoma is a recently recognized tumor entity. We report a case of epithelioid angiomyolipoma of the kidney that occurred in a 70-year-old female. The patient presented with massive abdominal hemorrhage and shock. There was no history of tuberous sclerosis complex. The tumor consisted of smooth muscle, adipocytes, small-to-medium-sized hyalinized blood vessels and numerous pleomorphic epithelioid cells with clear to eosinophilic cytoplasm. Mitosis was exceptional and no glandular pattern was recognizable. Immunohistochemically the epithelioid cells were strongly positive for HMB45 and CD68, focally positive for S-100, actin and vimentin, and negative for epithelial markers including epithelial membrane antigen and cytokeratins. Previous reports in the English literature suggest that epithelioid angiomyolipoma may have malignant potential. In our case, at six months from surgery the patient is alive and well without evidence of relapse or metastasis.

Renal Angiomyolipoma: Report of three cases with Regional Lymph Node Involvement and/or with Renal Cell Carcinoma

Aims and background

Angiomyolipomas (AMLs) are benign hamartoid tumors which frequently occur in tuberous sclerosis (TS). They may be manifest at different organ sites such as kidneys, lymph nodes, liver and lung and may be associated with renal cell carcinoma (RCC). The nature of multiple organ involvement in AML (metastasis versus multicentric synchronous tumors), the malignant transformation and the relation of AML to RCC have not been sufficiently clarified.

Study design

Three cases of renal AMLs in patients with tuberous sclerosis associated with lymphangioleiomyomatosis of the paraaortic lymph nodes and/or with RCC are reported. The concise clinical history of the patients as well as the findings of histology, immunohistochemistry and quantitative DNA analysis are presented.

Results

The multicentric form of AML and coincidence of renal AML and RCC were observed in 2 patients. AML and RCC were found within the same focus in one of the cases. RCCs were either aneuploid or “near diploid”, whereas one of the multicentric AMLs showed a discordant DNA ploidy pattern, namely aneuploidy in the kidney and diploidy in the lymph nodes.

Conclusions

The presented cases (all of them underwent periaortic lymphadenectomy) suggest that lymph node involvement in renal AML may be more frequent than expected (1-2% of all AMLs) on the basis of the few reported cases. The discordant DNA ploidy (renal versus lymph node lesions) observed in one of the cases with multicentric AML implies synchronous tumor growth at different sites rather than metastatic disease. The intimate coexistance of RCC and AML (RCC revealed by immunohistochemistry within a larger mass of renal AML) may indicate that malignant transformation of an AML should only be accepted, if such a coincidence is unequivocally excluded.

An update on recent developments in rupture of renal angiomyolipoma

BACKGROUND

Renal angiomyolipoma (AML) is a common benign tumor of the kidney. The main complication of AML is retroperitoneal hemorrhage caused by AML rupture, which can be severe and life threatening. The risk of AML rupture used to be determined by tumor size. However, these criteria have been challenged by series of clinical studies and case reports, suggesting prediction AML rupture based on tumor size is not always reliable.

METHODS

The authors searched PubMed using "angiomyolipoma," "AML," and "rupture" and reviewed relevant studies. The authors investigated the risk factors of AML rupture using the retrieved literature. The authors also summarized current modalities to evaluate and manage AML.

RESULTS

It is established that risk of AML rupture is associated with lesion size. However, genetic abnormality, aneurysm formation, and pregnancy are also risk factors for tumor rupture. Thus, the prediction of AML rupture should be based on a more comprehensive risk assessment system. The management of renal AML and tumor rupture was also discussed in the present paper.

CONCLUSION

The risk of AML rupture is associated with but not exclusive to lesion size. Any decision to intervene AML must be based on multiple factors including risk, symptoms, and auxiliary findings.

[A Case of Bilateral Angiomyolipoma Accompanied by Tuberous Sclerosis Complex Successfully Treated with Transcatheter Arterial Embolization Using Functional Kidney Mapping Images Consisting of SPECT-CT and Contrast Enhanced CT Images]

Renal angiomyolipoma (AML) and aneurysm are common in tuberous sclerosis complex (TSC) and represent the main causes of morbidity in adults with TSC. Herein, we report a 22-year-old woman with TSC-associated AMLs and renal aneurysms. She was referred to our hospital for the treatment of multiple renal aneurysms larger than 5 mm in diameter. The previous hospital considered that transcatheter arterial embolization (TAE) of bilateral renal aneurysms would cause deterioration of renal function. To estimate the impact of TAE on renal function, we superimposed contrast enhanced computed tomography (CT) over single-photon emission CT (SPECT)-CT. This fusion image, referred to as functional kidney mapping image, revealed the location of renal arteries and aneurysms, and normal renal parenchyma simultaneously. Functional kidney mapping image was useful to distinguish the AML region from the normal renal parenchyma, and revealed that the planned embolization site was a non-functioning parenchyma. Therefore, TAE for her multiple renal aneurysms was successfully performed without deterioration of her renal function.

The effect of everolimus on renal angiomyolipoma in pediatric patients with tuberous sclerosis being treated for subependymal giant cell astrocytoma

BACKGROUND

Patients with tuberous sclerosis complex (TSC) often have multiple TSC-associated hamartomas, particularly in the brain and kidney.

METHODS

This was a post hoc analysis of pediatric patients being treated for subependymal giant cell astrocytomas (SEGAs) during the phase 3, randomized, double-blind, placebo-controlled EXIST-1 trial. Patients were initially randomly assigned to receive everolimus 4.5 mg/m²/day (target blood trough 5-15 mg/dl) or placebo and could continue in an open-label extension phase. Angiomyolipoma response rates were analyzed in patients aged <18 years with ≥1 target angiomyolipoma lesion at baseline. Response was defined as the proportion of patients with a ≥50% reduction in the sum volume of target renal angiomyolipomata from baseline, in the absence of new target angiomyolipomata, a >20% increase in kidney volume from nadir, and angiomyolipoma-related bleeding ≥ grade 2. Tolerability was also assessed.

RESULTS

Overall, this analysis included 33 patients. Renal angiomyolipoma response was achieved by 75.8% of patients (95% confidence interval, 57.7-88.9%), with sustained mean reductions in renal angiomyolipoma volume over nearly 4 years of treatment. In addition, most (≥80%) achieved clinically relevant reductions in angiomyolipoma volume (≥50%), beginning at week 24 and continuing for the remainder of the study. Everolimus was generally well tolerated in this subgroup, with most adverse events being grade 1 or 2 in severity.

CONCLUSIONS

Although everolimus is currently not indicated for this use, this analysis from EXIST-1 demonstrates its long-term efficacy and safety for the treatment of renal angiomyolipoma in pediatric patients undergoing treatment for TSC-associated SEGA.

Treatment effect of mTOR-inhibition on tissue composition of renal angiomyolipomas in tuberous sclerosis complex (TSC)

Purpose

Tuberous sclerosis complex (TSC)-associated renal angiomyolipoma (AML) have a high lifetime risk of acute bleeding. MTOR-inhibitors are a promising novel treatment for TSC-AML, however adequate response to therapy can be difficult to assess. Early changes in MRI signal may serve as a novel early indicator for a satisfactory response to mTOR-inhibitor therapy of AML.

Materials and methods

Thirty-eight patients with the definite diagnosis of tuberous sclerosis receiving everolimus therapy and n = 19 patients without specific therapy were included. 1.5 Tesla MRI was performed including sequences with a selective fat suppression. Patients were investigated prior to the initiation of therapy (baseline) and after <3 months (n = 21 patients), 3 to 6 months (n = 32) and 18 to 24 months (n = 28). Signal and size changes of renal AMLs were assessed at all different timepoints. Signal-to-noise-ratio (SNR), contrast-to-noise-ratio (CNR) and size of angiomyolipomas were evaluated.

Results

Signal changes in 273 AMLs were evaluated. A significant and strong decrease of the CNR of AMLs following the initiation of therapy was measured in the fat-suppressed MR sequence at all time points, compared to the baseline: From 7.41±6.98 to 3.84±6.25 (p ≤ 0.05p = 0.002), 3.36±6.93 (p<0.0001), and 2.50±6.68 (p<0.0001) after less than 3 months, 3–6 months or 18–24 months of everolimus treatment, respectively. Also, a significant, however less pronounced, reduction of angiomyolipoma size in the different groups was measured (from baseline 2022.2±2657.7 mm2 to 1854.4±1670.9 mm2 (p = 0.009), 1875.5±3190.1 mm2 (p<0.001), and 1365.8 ± 1628.8 mm2 (p<0.0001) after less than 3 months, 3–6 months or 18–24 months of everolimus treatment, respectively). No significant changes in CNR (p>0.05) and size (p>0.05) were measured in the control group.

Conclusion

mTOR inhibitor therapy in TSC patients results in an early and pronounced fatty transformation of AMLs on MRI. Fatty transformation could represent a novel early indicator of response to therapy in this patient collective.

Outcomes of angioembolization and nephrectomy for renal angiomyolipoma associated with tuberous sclerosis complex: a real-world US national study

OBJECTIVE

To examine outcomes of clinical procedures for renal angiomyolipoma associated with tuberous sclerosis complex (TSC) based on US national health claims databases.

METHODS

This retrospective cohort study selected two cohorts of TSC patients, who underwent either embolization or nephrectomy (either partial or complete) for renal angiomyolipoma in the years from 2000 through 2011. Based on claims diagnosis codes, we estimated the prevalence rates of 10 angiomyolipoma-related conditions and 50 embolization- or nephrectomy-related conditions in the pre- and post-baseline periods respectively, and made cross-year and cross-period comparison of these rates with repeated measures analysis methods.

RESULTS

The embolization cohort (N = 4280) and the nephrectomy cohort (N = 3842) had mean baseline ages of 50.7 and 51.7 years with 52.5% and 51.3% males, respectively. After the intervention, the embolization cohort had statistically significant reductions (all p < .05) in gross hematuria (-27.7%), retroperitoneal hemorrhage (-8.4%), and abdominal mass (-6.9%), and increases in hypertension (15.5%), renal mass or unspecified disorder of kidney and ureter (13.8%), anemia (5.1%), and renal insufficiency (3.3%). Similarly, the nephrectomy cohort saw statistically significant reductions (all p < .05) in gross hematuria (-30.6%), flank pain (-7.5%), and abdominal mass (-6.4%), but increases in hypertension (11.9%), renal insufficiency (10.4%), and anemia (7.6%). Embolization was associated with post-procedure increases in renal mass or unspecified kidney/ureter disorder (13.9%), other disorders of kidney and ureter (3.4%), non-acute renal insufficiency (3.1%), flank pain (3.7%), renal insufficiency (3.2%), etc. (all p < .05). Nephrectomy was associated with post-procedure increases in postoperative ileus (5.3%), pain and headache (4.8%), paralytic ileus (3.6%), etc. (all p < .05).

CONCLUSIONS

Both embolization and nephrectomy were effective, but associated with increases in certain angiomyolipoma-related conditions. Further, the embolization effect on gross hematuria, retroperitoneal hemorrhage, and abdominal mass might subside after the intervention year.

Healthcare utilization and costs in patients with tuberous sclerosiscomplex-related renal angiomyolipoma

OBJECTIVE

To quantify healthcare utilization and costs in patients with tuberous sclerosis complex (TSC) and renal angiomyolipoma (AML) in a matched cohort of patients without TSC or AML.

METHODS

Administrative data from the MarketScan Research Databases were used to select patients with TSC and renal AML during January 1, 2000-March 31, 2013 from the Commercial database and January 1, 2000-June 30, 2012 from the Medicaid database. Patients were required to have at least 30 days of follow-up from initiation into the study, and were followed until inpatient death, end of insurance coverage, or the end of study. Age, calendar year, and payer-matched controls that had no TSC and no AML were selected. All-cause annualized healthcare utilization and costs were calculated by service category.

RESULTS

A total of 218 patients under 18 years and 377 patients 18 years and older with TSC-renal AML were selected from the Commercial database, and matched to 654 and 1,131 controls, respectively. Thirty-eight patients under 18 years and 110 patients 18 years or older with TSC-renal AML were selected from the Medicaid database, and matched to 54 and 212 controls, respectively. Within the Commercial cohort, and across both age groups, TSC-renal AML patients utilized more healthcare services than their matched controls. Within the Medicaid cohort, in both age groups, utilization was higher in TSC-renal AML patients vs control patients for inpatient admissions, emergency room visits, physician office visits, and hospital-based outpatient visits. Across age groups and in both the Commercial and Medicaid cohorts, the annual average total costs were significantly higher in TSC-renal AML patients compared to control patients (p < 0.05 for all). Healthcare costs ranged from $29,240-$48,499 for TSC-renal AML patients and from $2,082-$10,864 for control patients.

CONCLUSIONS

Compared to controls, TSC-renal AML patients incurred substantially higher annual healthcare utilization and costs.

Microsatellite analysis for differentiating the origin of renal angiomyolipoma and involved regional lymph node

Renal angiomyolipoma (AML) with the regional lymph node (LN) involved leads to a question of metastasis versus multicentric origin when their histology are similar. As the genomic instability is a common feature of cancer, we hypothesized that independently arising neoplasms in an individual patient would exhibit measurable genomic variation, facilitating the discrimination of tumor lineage and relatedness. Our study enrolled 12 patients who were diagnosed with nodal-involved renal AML at West China Hospital. Genomic DNA from kidney and lymph node lesion from individuals was analyzed through PCR-based analysis which using six microsatellite markers to identify discordant allelic variation. The results showed all 12 patients underwent surgical treatment and none suffered local recurrence or distant metastasis during the follow-up. Ten patients of the included cases showed a consistent trend that all corresponding to six microsatellite markers were detected in DNA from renal AMLs but were reduced or not observed in DNA from the paired LN. With this technique, a possible lineage relationship cannot be excluded between renal AMLs and LN. Thus when enlarged LN were found in images, active surveillance should be taken into consider; if enlarged LN were found intraoperatively, LN resection might be necessary to demonstrate their pathological nature.

[Tuberous Sclerosis Complex Detected by Spontaneous Rupture of a Giant Renal Angiomyolipoma : A Case Report]

A woman in her 30s was admitted with abdominal pain and nausea. CT scan revealed a spontaneous rupture of the right giant renal angiomyolipoma, and trans-arterial embolization was performed successfully. With further examination, she was found to be affected with tuberous sclerosis complex (TSC) and she finally wastreated with everolimusfor prevention of recurrent spontaneous-rupture of renal angiomyolipoma.

Cesarean Section Revealing an Unsuspected Renal Angiomyolipoma in a Woman with Severe Hypertension During Pregnancy: A Case Report

BACKGROUND

Renal angiomyolipomas are uncommon during pregnancy, but it is important to consider them in the differential diagnosis, for the increased risk of complications such as bleeding, renal artery compression, and renovascular hypertension.

CASE

A 42-year-old woman was admitted at 34 weeks of gestation for severe abdominal pain in the right flank associated with severe hypertension. During the postadmission immediate cesarean section for fetal compromise, abdominal exploration revealed a massive retroperitoneal hematoma (around 30 cm) up to the cecal region until the lower edge of the liver. The diagnosis was the rupture of a renal angiomyolipoma causing renovascular hypertension.

CONCLUSION

Renovascular hypertension should be considered in patients who present with accelerated hypertension, particularly if the hypertension is resistant to medical therapy and not associated with laboratory features of preeclampsia/eclampsia.

[Chronic kidney diseases do not always pass unnoticed]

Kidney diseases are frequent, but most of the time, they develop unnoticed. This paucity of symptoms may lead to delayed diagnosis with important consequences on their outcome. Nevertheless, specific systemic signs such as skin lesions, joint pain or electrolytes disturbances may sometimes alert the clinician and direct the diagnosis to an underlying nephropathy. A high awareness of clinicians is warranted to recognize these red flags and diagnose these diseases early, as illustrated by two clinical cases discussed in this article.

Multidetector Computed Tomography Features in Differentiating Exophytic Renal Angiomyolipoma from Retroperitoneal Liposarcoma: A Strobe-Compliant Observational Study

This study aims to evaluate the multidetector computed tomography (CT) imaging features in differentiating exophytic renal angiomyolipoma (AML) from retroperitoneal liposarcoma. We retrospectively enrolled 42 patients with confirmed exophytic renal AML (31 patients) or retroperitoneal liposarcoma (11 patients) during 8 years period to assess: renal parenchymal defect at site of tumor contact, supply from branches of renal artery, tumoral vessel extending through the renal parenchyma, dilated intratumoral vessels, hemorrhage, non-fat-containing intratumoral nodules with postcontrast enhancement, calcification, renal sinus enlargement, anterior displacement of kidneys, and other associated AML. Renal parenchymal defect, renal arterial blood supply, tumoral vessel through the renal parenchyma, dilated intratumoral vessels, intratumoral/perirenal hemorrhage, renal sinus enlargement, and associated AML were seen only or mainly in exophytic renal AML (all P value < 0.05); however, non-fat-attenuating enhancing intratumoral nodules, intratumoral calcification, and anterior displacement of the kidney were more common in liposarcoma (all P value < 0.05). AMLs reveal renal parenchymal defect at the site of tumor contact, supply from renal artery, tumoral vessel extending through the renal parenchyma, dilated intratumoral vessels, intratumoral and/or perirenal hemorrhage, renal sinus enlargement, and associated AML. Non-fat-attenuating enhancing intratumoral nodules, intratumoral calcifications, and anterior displacement of kidney were more commonly seen in liposarcoma.

A rare case of xanthogranulomatous pyelonepheritis with hepatic angiomyolipoma

Xantogranulomatous pyelonephritis (XGP) is a rare and chronic variant of pyelonephritis typically associated with obstruction and infection. Xantogranulomatous pyelonephritis can infiltrate liver and connect with hepatic dysfunction. Here we report on a 52-year-old female with a liver mass and a left renal mass detected by uitrasonography and magnetic resonance imaging. Right lobectomy and partial nephrectomy were successively performed. Subsequent pathologic examination indicated hepatic angiomyolipoma and xanthogranulomatous pyelonepheritis, respectively. To the best of our knowledge, this is the first case of such rare combination.

[Renal angiomyolipoma with spontaneous retroperitoneal bleeding]

Angiomyolipoma (AML) is a benign tumour composed predominantly of blood vessels, smooth muscle tissue and adipose tissue. It is a rare disorder found in 0.1% of men and 0.22% of women. AML is most often manifested as a solitary tumour, but can also be found with multiple lesions in various organs. AML is predominantly asymptomatic, but may present with different symptoms depending on the size and position. Patients often have flank pain and microscopic or macroscopic haematuria. AML can also debut with spontaneous atraumatic bleeding in the retroperitoneum, Wunderlich's syndrome.

Renal Angiomyolipoma With Caval Extension and Pulmonary Fat Embolism: A Case Report

Renal angiomyolipoma (AML) is a rare benign tumor of the kidney. Occasionally, it may extend into the renal vein or the inferior vena cava (IVC), but so far of pulmonary embolism in patients with renal AML was rarely reported. Here, a case of symptomatic pulmonary embolism secondary to AML that was placed IVC filter before the operation and then treated with radical nephrectomy is reported.This case highlights the rare possibility of renal vein and IVC involvement with symptomatic pulmonary fat embolism in renal AML, which may potentially result in fatal complications if not appropriately and cautiously managed with surgical intervention.