We present a case of pulmonary metastasis originating from renal angiomyolipoma (AML), as evidenced by whole-exome sequencing (WES) analysis. Although AML predominantly arises in the kidneys, it can emerge in various body parts, making it important to distinguish between multicentric development and metastasis. However, previous studies have not distinguished between these conditions. Our case features an 82-year-old woman with a history of renal AML who presented with multiple, randomly distributed, bilateral pulmonary nodules of varying size and pure fat densities. The patient\'s condition followed a benign course over 10 years. Through WES, we discovered shared mutations in pulmonary lesions that were absent in the patient\'s blood, including a pathological mutation in TSC2, suggesting a metastatic origin from renal AML. Knowledge of the pulmonary manifestations of AML and their distinctive imaging findings can help radiologists and clinicians diagnose and manage patients with similar presentations.

Background: Renal angiomyolipoma (AML) without local invasion is generally considered benign. However, it may extend to the renal sinus, even the renal vein, or the inferior vena cava (IVC). In patients with non-tuberous sclerosis complex, coexistence of renal cell carcinoma (RCC) and renal AML is uncommon. Case presentation: A 72-year-old woman was incidentally found to have a solitary right renal mass with an IVC thrombus extending into the right atrium during a routine health checkup. Robot-assisted laparoscopic radical nephrectomy and thrombectomy were successfully performed through adequate preoperative examination and preparation. Two tumor lesions were found and pathologically confirmed as renal AML and RCC, and the tumor thrombus was derived from the renal AML. During the one-year follow-up period, no signs of recurrence or metastatic disease were observed. Conclusions: Renal AML with a tumor thrombus in the IVC and right atrium accompanied by RCC may occur, although rarely. In clinical practice, if preoperative manifestations differ from those of common diseases, rare diseases must be considered to avoid missed diagnoses. In addition, adequate examination and multidisciplinary discussions before making a diagnosis are necessary. For a level 4 tumor thrombus with no infringement of the venous wall, adoption of robot-assisted minimally invasive surgery, without extracorporeal circulation technology, is feasible.

UNASSIGNED: This is a case of giant renal angiomyolipoma treated with partial nephrectomy without pre-embolization of the supplying arteries.
METHODS: The patient presented for regular checkup, a mass in the left flank was found on examination. No other symptoms were present. No history of medical or surgical importance was found.
UNASSIGNED: CT scan revealed a heterogenous mass in the left kidney at the upper pole. The treatment options were discussed with the patient and he opted for complete removal of the mass. Partial nephrectomy was done without pre embolization of the arteries. The procedure went without complications, the blood loss was manageable during the operation (200 cc). The patient was admitted for 48 h post operation and was discharged shortly after. The excised mass was sent for histopathological examination, the report was received, the features of the mass was consistent with angiomyolipoma without other types of malignant masses present.
CONCLUSIONS: The takeaway is that partial nephrectomy provides a convenient option for treatment of giant renal angiomyolipomas. Preservation of the renal function, reduction of the recurrence risk or re embolization of the supplying arteries makes it a viable alternative for other treatment modalities.

暂无摘要。

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.

Renal angiomyolipoma (rAML) is a rare benign tumour primarily affecting women due to hormonal influences, with accelerated growth observed during pregnancy. This case report presents a multigravida woman in her mid-20s at 37 weeks of gestation with stable vital signs and normal physical examination findings, except for swelling in the lower extremities. Following caesarean section delivery, she developed flank pain and haematuria in the immediate postoperative period. Emergency surgery revealed a ruptured rAML, resulting in unstable haemodynamics and significant blood loss. A multidisciplinary team performed a left radical nephrectomy to control bleeding. The patient required transfusions, ventilation and postoperative antibiotic therapy. This case underscores the importance of considering rAML rupture in the immediate postoperative period following caesarean section, highlighting the need for prompt evaluation in pregnant women with a history of urologic disorders.

Renal angiomyolipoma (AML) is a benign mesenchymal tumor composed of fat, smooth muscle, and blood vessels. It represents 1-3% of solid renal tumors. Despite the benign nature of this tumor, it can be aggressive with locoregional extension. We describe a case of a 60-year-old female who presented with left flank pain and unstable blood pressure. A CT scan showed a renal mass with hemorrhagic densities. Peroperatively, bleeding from the renal mass was revealed, and the patient underwent radical nephrectomy. A myriad of symptoms such as acute flank pain, flank mass, and bleeding led to the diagnosis of Wunderlich syndrome, which is usually seen secondary to AML and renal cell carcinoma. Histopathologic examination helped in arriving at the diagnosis of renal AML with secondary changes, ruling out malignancy. Early diagnosis and immediate intervention saved her life and reduced morbidity. This case report helps in sensitizing clinicians and thus facilitates the detection of similar cases at the earliest.

Renal angiomyolipoma is a benign mesenchymal tumor that can be divided into classical and other subtypes. Angiomyolipoma with epithelial cysts (AMLEC) is an extremely rare non classical subtype. AMLEC without fat component is even rarer. We report a case of AMLEC without fat in a 29-year-old man who was provisionally diagnosed with cystic renal carcinoma by ultrasonography, abdominal enhanced CT and MRI. He had no complaints, or personal or family history of TSC, or other malignancies. Based on imaging findings, robot-assisted laparoscopic nephron-sparing partial nephrectomy through a retroperitoneal approach was performed for the purpose of both diagnosis and treatment. We diagnosed AMLEC after considering the differential diagnosis of other cystic renal neoplasms, such as cystic renal carcinoma, multilocular cystic renal cell neoplasm of low malignant potential, adult cystic nephroma and mixed epithelium and stromal tumor. Meanwhile, the whole-exon sequencing (WES) results showed insert-splicing mutation in the 21st exon and 20th exon of the TSC1 gene. No treatments were performed after the operation and no evidence of recurrence or metastasis at regular follow-up.

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.
CONCLUSIONS: 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.

Tuberous sclerosis complex (TSC) is an autosomal dominant disease characterized by the development of hamartomas in the central nervous system, heart, skin, lungs, and kidneys and other manifestations including seizures, cortical tubers, radial migration lines, autism and cognitive disability. The disease is associated with pathogenic variants in the TSC1 or TSC2 genes, resulting in the hyperactivation of the mTOR pathway, a key regulator of cell growth and metabolism. Consequently, the hyperactivation of the mTOR pathway leads to abnormal tissue proliferation and the development of solid tumors. Kidney involvement in TSC is characterized by the development of cystic lesions, renal cell carcinoma and renal angiomyolipomas, which may progress and cause pain, bleeding, and loss of kidney function. Over the past years, there has been a notable shift in the therapeutic approach to TSC, particularly in addressing renal manifestations. mTOR inhibitors have emerged as the primary therapeutic option, whereas surgical interventions like nephrectomy and embolization being reserved primarily for complications unresponsive to clinical treatment, such as severe renal hemorrhage. This review focuses on the main clinical characteristics of TSC, the mechanisms underlying kidney involvement, the recent advances in therapy for kidney lesions, and the future perspectives.