Imaging appearance of renal epithelioid angiomyolipoma: A case report and literature review

Spontaneous rupture and hemorrhage of renal epithelioid angiomyolipoma misdiagnosed to renal carcinoma: a case report

BACKGROUND

Renal epithelioid angiomyolipoma is a rare and unique subtype of classic angiomyolipoma, characterized by the presence of epithelioid cells. It often presents with nonspecific symptoms and can be easily misdiagnosed due to its similarity to renal cell carcinoma and classic angiomyolipoma in clinical and radiological features. This case report is significant for its demonstration of the challenges in diagnosing epithelioid angiomyolipoma and its emphasis on the importance of accurate differentiation from renal cell carcinoma and classic angiomyolipoma.

CASE PRESENTATION

A 58-year-old Asian female presented with sudden left flank pain and was initially diagnosed with a malignant renal tumor based on imaging studies. She underwent laparoscopic radical nephrectomy, and postoperative histopathology confirmed the diagnosis of epithelioid angiomyolipoma. The patient recovered well and is currently in good health with regular follow-ups. This case highlights the diagnostic challenges, with a focus on the clinical, radiological, and histopathological features that eventually led to the identification of epithelioid angiomyolipoma.

CONCLUSIONS

Epithelioid angiomyolipoma is easily misdiagnosed in clinical work. When dealing with these patients, it is necessary to make a comprehensive diagnosis based on clinical symptoms, imaging manifestations, and pathological characteristics.

Spontaneous Rupture of Large Angiomyolipoma of the Kidney: A Rare Case

Angiomyolipoma is the most frequent neoplasm of the kidney. It may have a wide range of clinical manifestations, but it is usually detected incidentally on cross-sectional images. Rupture and hemorrhage of angiomyolipoma is an important concern for large lesions. We present the case of a 42-year-old female, with no history of urinary stones, who presented with a sudden-onset left flank pain for eight hours. Upon examination, she was tachycardic and hypotensive. Abdominal examination revealed a left-sided flank mass. Abdominal computed tomography (CT) scan with intravenous contrast demonstrated a heterogeneous mass lesion in the left kidney with mixed attenuation and had a macroscopic fat density that was surrounded by a large hematoma. Subsequently, transcatheter renal artery embolization was performed with no complications. The procedure was able to control the active bleeding. Then, a total nephrectomy was performed, and the hematoma was evacuated during laparotomy. Spontaneous nontraumatic renal hemorrhage is a very rare condition. Clinicians should keep a high index of suspicion for this condition when they encounter a patient with the clinical triad of flank pain, flank mass, and hypotension. The case demonstrated the role of endovascular embolization of angiomyolipoma to control life-threatening hemorrhage.

Renal Epithelioid Angiomyolipoma: A Case Report and Review of Literature

Epithelioid angiomyolipoma (EAML) is an uncommon renal neoplasm with malignant potential. It is classified under the group of perivascular epithelioid cell tumors and can be sporadic or as part of the tuberous sclerosis complex. On imaging, unlike classical AML that contains fat, EAML has a very low percentage of fat which can mimic the imaging findings of renal cell carcinoma. We reported a 31-year-old female who had a history of renal failure and bilateral renal masses. Magnetic resonance imaging of the abdomen revealed bilateral large renal masses replacing renal parenchyma with features suggestive of bilateral renal AML. The patient underwent left nephrectomy, and histopathology examination findings were consistent with the diagnosis of EAML.

Renal Epithelioid Angiomyolipoma: A Case Report and Review of Literature

Epithelioid angiomyolipoma (EAML) is an uncommon renal neoplasm with malignant potential. It is classified under the group of perivascular epithelioid cell tumors and can be sporadic or as part of the tuberous sclerosis complex. On imaging, unlike classical AML that contains fat, EAML has a very low percentage of fat which can mimic the imaging findings of renal cell carcinoma. We reported a 31-year-old female who had a history of renal failure and bilateral renal masses. Magnetic resonance imaging of the abdomen revealed bilateral large renal masses replacing renal parenchyma with features suggestive of bilateral renal AML. The patient underwent left nephrectomy, and histopathology examination findings were consistent with the diagnosis of EAML.

Partial nephrectomy can be a successful treatment option for renal epithelioid angiomyolipoma: a case report and literature review

Background

Renal epithelioid angiomyolipoma is a rare tumour which involves kidneys in most cases. It is known for its aggressive behaviour as a significant number of cases have been associated with metastatic epithelioid angiomyolipoma. Usually, radical treatment with systemic therapy is recommended. Only a small number of cases of epithelioid angiomyolipomas have been reported with the standard treatment being radical or partial nephrectomy. We present a  case report showing that partial nephrectomy can be a successful treatment option for renal epithelioid angiomyolipoma. This is the first case of this nature in Lithuania.

Case presentation

In this case, a 40-year-old male with epithelioid angiomyolipoma of the left kidney is presented. In 2012, a cystic left renal mass 40 × 41 mm in size was diagnosed incidentally while performing ultrasound and later confirmed by MRI. Due to the size of the tumour and the possibility of renal cell carcinoma, surgery was scheduled. Left partial nephrectomy was performed successfully. Final pathology report came back with the diagnosis of renal epithelioid angiomyolipoma. The patient had yearly follow-up for six years by CT scan, and neither recurrence nor progression were observed.

Conclusions

Early detection and diagnosis are crucial for treatment as the tumour tends to have malignancy potential. With early diagnosis, partial nephrectomy can be performed with yearly follow-up and no systemic treatment required.

Huge renal epithelioid angiomyolipoma - A case report of a giant, benign renal mass

INTRODUCTION

Renal angiomyolipoma (also called renal hamartoma) is a benign Tumor, composed of adipose tissue, smooth muscle tissue, and blood vessels. Tumors more than 10 cm (referred to as "giant" AMLs) are infrequent and a very small number of reported cases were measured more than 20 cm. Epithelioid angiomyolipoma (EAML), is a rare variant of angiomyolipoma with malignant potential. There are less than 10 cases of huge EAML reported in English literature, that were all associated with recurrence and complications.

CASE PRESENTATION

Here we report a rare case of renal EAML in a 48-year-old male patient that was not associated with tuberous sclerosis. He was admitted to our hospital with a complaint of severe abdominal pain. Computer Tomography Scan (CT-scan), revealed two masses attached to the left kidney with a size of 32 × 22 × 8 cm and 20 × 10 × 3 cm. The patient underwent a radical left nephrectomy. Postoperative histopathological examination confirmed the diagnosis of an EAML. The two-year follow-up CT-scan showed no recurrence.

CONCLUSION

Malignant EAML, although rare, does exist. Thus, besides evaluations required for ruling out the diagnosis of renal sarcomas, surgeons must follow patients after total nephrectomy for possible recurrence. Benign cases can be completely cured by surgery and do not show recurrence at the end of the follow-up period.

Imaging of Unusual Renal Tumors

PURPOSE OF REVIEW

Renal masses are a wide entity and a common finding in clinical practice. Detection of these masses has increased in the last years, yet mortality rates have slightly decreased.

RECENT FINDINGS

According to the World Health Organization classification, there are 8 types, 51 subtypes, and a lot more subsequent subclassifications of renal tumors. Histopathological analysis should always be assessed for final diagnosis of theses tumors. However, imaging can be an important diagnostic guidance. The most common diagnoses of renal tumor are clear cell carcinoma, papillary renal cell carcinoma, angiomyolipoma, and transitional cell carcinoma. Nonetheless, a considerable variety of particular tumors can arise from the kidney, challenging the expertise of radiologists and urologists on this subject. The awareness of these unusual entities is vital for professionals working at a complex medical facility with greater volume of patients. We hereby present uncommon renal tumors and its pathological and radiological features.

Malignant perivascular epithelioid cell tumor in the female genital tract: Preferred reporting items for systematic reviews and meta-analyses

BACKGROUND

Perivascular epithelioid cell tumor (PEComa) is a rare mesenchymal tumor, located at various anatomic sites, including the female genital tract. This study aimed to evaluate the clinicopathological characteristics of patients with PEComa arising from the female genital tract.

METHODS

A retrospective study was conducted in Taipei Veterans General Hospital (Taipei VGH) between 2008 and 2018. All published English cases based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement were also included in the current review.

RESULTS

A total of 114 women from PRISMA and 3 women from Taipei VGH were identified. The uterus was the most commonly involved site (82/114, 71.9%), followed by the cervix (12/114, 10.5%). Immunohistochemical staining showed that nearly all gynecological PEComas were positive for human melanoma black 45 (113/114, 99.1%). More than half of the gynecological PEComas were immunoreactive for desmin (50/85, 58.8%). Multi-modality treatment, including surgery and mammalian target of rapamycin (mTOR) inhibitors as targeted therapy, provided long-term disease-free survival (cure rate ranging from 50% to 100%, based on the different anatomic sites of the female genital tract).

CONCLUSION

Multi-modality treatment, including cytoreductive surgery and mTOR inhibitors with/without chemotherapy and/or radiation, should be considered for the management of women with PEComas in the genital tract.

Does epithelioid angiomyolipoma have poorer prognosis, compared with classic angiomyolipoma?

Purpose

Classic angiomyolipoma (AML) is common benign kidney tumor. However, some studies have claimed that epithelioid angiomyolipoma (EAML) has malignant potential. We compared the patient characteristics and prognosis of EAML and classic AML to demonstrate predicting factors and poorer prognosis of EAML.

Materials and Methods

The medical records of 231 patients who were diagnosed with EAML (n=27, 11.7%) or classic AML (n=204, 88.3%), were reviewed. All patients underwent computed tomography (CT) scans before operation or needle biopsy. We assessed the age, sex, tumor size, body mass index, comorbidities, and Hounsfield unit (HU) according to each CT phase. We defined the unfavorable group as patients with recurrence, metastasis and death due to tumor progression. Logistic regression analysis was used to predict EAML.

Results

EAML patients were younger (41.2 years vs. 49.1 years, p=0.001), predominantly male (55.6% vs. 28.4%, p=0.005), and had a larger tumor (7.5 cm vs. 4.2 cm, p<0.001). The median pre-contrast HU was not significantly different between EAML and classic AML (29.9±23.7 vs. 14.7±41.0, p=0.071). In multivariable analysis, younger age (odds ratio [OR], 0.96; p=0.032), male sex (OR, 3.33; p=0.013), and tumor larger than 4 cm (OR, 3.8; p=0.009) were significant predictive factors. Five patients (18.5%) had unfavorable outcomes, two patients had lymph node metastasis, and three patients had lung metastasis.

Conclusions

Patient and tumor characteristics can be helpful in determining the type of AML preoperatively. Younger age, male sex, and larger tumor mass may increase the possibility of diagnosing EAML. EAML has malignant potential and requires careful follow-up.