Malignant epithelioid angiomyolipoma: tumor and metabolic response to everolimus as evaluated with positron emission tomography

Clinical and pathological features of renal epithelioid angiomyolipoma (PEComa): A single institution series

Renal angiomyolipomas are benign tumors of the kidney that belong to the 'PEComa: perivascular epithelioid cell' family. Epithelioid AMLs (eAML) are a rare monotypic subtype with malignant potential, that can occur sporadically or be associated with tuberous sclerosis (TSC). Due to their epithelioid nature, eAMLs can closely resemble high-grade renal cell carcinoma (RCC), which may result in misdiagnosis. Multiple clinicopathologic parameters are predictive of worse outcomes for patients with eAML. Those can be used to stratify patients into groups with low, intermediate and high risk for disease progression. A high index of suspicion and a thorough immunohistochemical study are required to correctly diagnose eAML. Radiographically, eAMLs are also a diagnostic challenge as they share features with RCC on CT and MR imaging. Due to this close mimicry, the true incidence of eAML is thought to be much higher than 200 cases as reported in the literature. We report a series of four patients diagnosed with eAML and compare their clinical courses. We also report on the successful treatment of a patient with pulmonary metastasis from eAML using the mTOR inhibitor, everolimus. By identifying eAML and recognizing its high-risk features, it is possible mTOR inhibitors may have a meaningful role in the adjuvant treatment of these patients.

Metastatic epithelioid angiomyolipoma treated with everolimus in a patient receiving hemodialysis: A case report

Introduction

A patient undergoing hemodialysis and being treated with everolimus for metastatic epithelioid angiomyolipoma has never been described in the literature, to our knowledge.

Case presentation

A 53‐year‐old woman who had undergone trans‐arterial embolization for epithelioid angiomyolipoma was referred with a chief complaint about right knee pain. Hemodialysis had been started after the embolization. Needle biopsy specimens of tumors obtained from behind the right kidney and in the right femur were diagnosed as epithelioid angiomyolipoma metastases. The patient underwent treatment with everolimus and achieved a partial response after 6 months of treatment without serious adverse events.

Conclusion

Everolimus might be effective for patients with metastatic epithelioid angiomyolipoma who are undergoing hemodialysis.

Sporadic Angiomyolipomas Growth Kinetics While on Everolimus: Results of a Phase II Trial

PURPOSE

Everolimus decreases tumor volume of renal angiomyolipomas in patients with tuberous sclerosis. No prospective data are available regarding the effect of everolimus on the growth kinetics in patients with sporadic angiomyolipomas. We sought to determine the safety and efficacy of everolimus in the volumetric reduction of sporadic angiomyolipomas.

MATERIALS AND METHODS

This multi-institutional, prospective, phase II trial, enrolled patients with 3 cm or larger sporadic angiomyolipomas who were candidates for surgical resection or percutaneous angioembolization. Patients received 10 mg everolimus daily for 4 planned 28-day cycles. Response was defined as a 25% or greater volumetric reduction of patient angiomyolipoma. Baseline, 4, 6 and 12-month volumetric analyses were performed using magnetic resonance imaging. Everolimus was discontinued in those with less than 25% volumetric reduction after 4 cycles. Those with 25% or greater volumetric reduction received 2 additional cycles. The primary outcomes were the efficacy of everolimus in the volumetric reduction of angiomyolipomas by 25% or more, and the safety and tolerability of everolimus.

RESULTS

Overall 20 patients were enrolled at 5 centers. Of these patients 11 (55%) completed 4 cycles and 7 (35%) completed 6 cycles. Efficacy was demonstrated, with 10 of 18 (55.6%) patients exhibiting a 25% or greater reduction in tumor volume at 4 months (median 58.5%) and 10 of 14 (71.4%) patients exhibiting a 25% or greater reduction in tumor volume at 6 months (median 58.2%). Four (20%) patients were withdrawn due to protocol defined toxicities and 8 (40%) self-withdrew from the study due to side effects.

CONCLUSIONS

Everolimus was effective in causing volumetric reduction of angiomyolipomas by 25% or greater in most patients but was associated with a high rate of treatment discontinuation.

Case report of everolimus-induced sustained partial response in metastatic renal epithelioid angiomyolipoma

Epithelioid variant of angiomyolipoma (EAML) is a newly defined entity and a close mimicker of renal cell carcinoma. There is a growing body of evidence to suggest its aggressive behavior in terms of local recurrence, metastasis and death. The treatment for this subset of patients has posed challenges for the experts. Chemotherapy plays little active role and so molecular profiling to identify genomic alterations amenable to targeted therapies has paved the way. Recently, tyrosine kinase inhibitors and mTOR inhibitors have been utilised both in adjuvant and neoadjuvant settings and have shown promising results in terms of survival. We present a case of a metastatic epithelioid angiomyolipoma treated sequentially with imatinib, crizotinib and now maintaining a sustained partial response with everolimus.

Malignant renal epithelioid angiomyolipoma with liver metastasis after resection: a case report with multimodality imaging and review of the literature

Renal epithelioid angiomyolipoma (EAML) is a perivascular epithelioid cell tumor. Although the overwhelming majority of renal EAMLs are benign, cases of aggressive behavior and malignancy have been reported. Here, we report the case of a 62-year-old woman with a 12.5-cm renal EAML, who underwent resection and developed a 10.5-cm hepatic EAML 15 months after the surgery. Although multicentric disease is a possibility, the temporal course is consistent with metastasis from the poorly differentiated primary tumor. This is the only report with multimodality imaging to detail new metastatic disease during surveillance after intended curative resection of an EAML.