Hepatic epithelioid angiomyolipoma is a rare and potentially severe but treatable tumor: A report of three cases and review of the literature

Clinical review and literature analysis of hepatic epithelioid angiomyolipoma in alcoholic cirrhosis: A case report

BACKGROUND

Hepatic epithelioid angiomyolipoma (HEA) has a low incidence and both clinical manifestations and imaging lack specificity. Thus, it is easy to misdiagnose HEA as other tumors of the liver, especially in the presence of liver diseases such as hepatitis cirrhosis. This article reviewed the diagnosis and treatment of a patient with HEA and alcoholic cirrhosis, and analyzed the literature, in order to improve the understanding of this disease.

CASE SUMMARY

A 67-year-old male patient with a history of alcoholic cirrhosis was admitted due to the discovery of a space-occupying lesion in the liver. Based on the patient's history, laboratory examinations, and imaging examinations, a malignant liver tumor was considered and laparoscopic partial hepatectomy was performed. Postoperative pathology showed HEA. During outpatient follow-up, the patient showed no sign of recurrence.

CONCLUSION

HEA is difficult to make a definite diagnosis before surgery. HEA has the potential for malignant degeneration. If conditions permit, surgical treatment is recommended.

Epithelioid hepatic angiomyolipoma in pregnancy: A case report

INTRODUCTION AND IMPORTANCE

Epithelioid hepatic angiomyolipoma (HAML) is a rare benign tumor predominantly found in women. Its occurrence during pregnancy is extremely rare. Accurate diagnosis of HAML is challenging due to its radiological resemblance to other hepatic neoplasms. We present a case of epithelioid HAML in a pregnant patient, highlighting the diagnostic and management challenges encountered.

CASE PRESENTATION

A 24-year-old pregnant female, in her fifth month of pregnancy, presented with right hypochondrium pain and nausea. Radiological imaging suggested the possibility of a hepatic adenoma. The patient opted to continue the pregnancy with regular monitoring of the mass as well as fetal health. After delivering a healthy baby, the patient underwent successful mass excision and cholecystectomy. Histopathology of the liver mass confirmed the diagnosis of epithelioid HAML.

CLINICAL DISCUSSION

Epithelioid HAML is a rare tumor often misdiagnosed. It is more aggressive and frequently associated with tuberous sclerosis complex (TSC) compared to other subtypes. The diagnosis of HAML can be challenging due to its resemblance to Hepatocellular Carcinoma and other hepatic neoplasms on radiological imaging. Immunohistochemistry plays a crucial role in confirming the diagnosis. Surgical excision is the recommended treatment, with complete removal to minimize the risk of recurrence.

CONCLUSION

This case report highlights the rarity of epithelioid HAML during pregnancy and emphasizes the importance of a multidisciplinary approach in managing hepatic neoplasms. Close monitoring is crucial, considering the potential risks to the mother and fetus. Accurate diagnosis through histopathological evaluation, immunohistochemistry and a multidisciplinary approach are essential for appropriate management.

Case report: Hepatic epithelioid angiomyolipoma with elevated alpha-fetoprotein and a history of breast cancer

Background

Perivascular epithelioid cell tumors have characteristic histological and immunohistochemical profiles. Epithelioid angiomyolipomas in the liver have particularly rare characteristics. These tumors are relatively small and lack clinical and imaging specificity. Thus, they can be easily misdiagnosed as other primary or metastatic tumors prior to surgery. Due to the significant epithelioid morphology and atypia of hepatic epithelioid angiomyolipoma (HEAML), intraoperative frozen section pathologic diagnosis might be challenging.

Case presentation

A 33-year-old woman was admitted to our hospital for elevated alpha-fetoprotein (AFP) levels after a regular checkup following breast cancer surgery. Initially, liver cancer was suspected based on enhanced magnetic resonance imaging and color Doppler ultrasonography. Her serum AFP levels were 23.05 ng/ml. The patient underwent laparoscopic right hepatic tumor resection. Based on intraoperative cryopathology, hepatocellular carcinoma was considered a likely diagnosis. However, postoperative pathology confirmed a right HEAML. The patient underwent regular checkups for 23 months without exhibiting recurrence or distant metastasis.

Conclusion

HEAML can be easily misdiagnosed on preoperative imaging and intraoperative cryopathology. Medical professionals must be aware of this possibility and proceed with caution. Postoperative pathological examination with assessment of IHC markers was helpful in diagnosing HEAML. HEAML has low malignant potential. Surgical resection is the mainstay of treatment, and most patients have a good prognosis.

Clinical and Contrast-enhanced Ultrasound Characteristics of Epithelioid and Classic Hepatic Angiomyolipoma: Comparison With Alpha-fetoprotein-negative Hepatocellular Carcinoma

Hepatic angiomyolipoma (HAML) comprises epithelioid angiomyolipoma (EAML) and classic hepatic angiomyolipoma (CAML). The imaging appearance of HAML varies widely, and EAML is more easily misdiagnosed as hepatocellular carcinoma (HCC) than as CAML. The clinical and contrast-enhanced ultrasound (CEUS) features of CAML, EAML and HCC with negative alpha-fetoprotein protein expression (HCC[AFP-]) were retrospectively reviewed. The hyper-vascular type was more commonly found in CAML and EAML lesions than in HCC lesions. Most lesions were hyper-enhanced in the arterial phase. CAMLs showed prolonged hyper-enhancement or iso-enhancement during the portal and late phases on CEUS, making them easily distinguishable from HCC(AFP-). Some EAML lesions (41.7%) were hypo-echoic, similar to HCC(AFP-). However, the hypo-enhancement of EAML lesions occurred later than that of HCC(AFP-) lesions. Thus, our findings may be useful in distinguishing among these lesions to improve diagnostic accuracy.

More than Pus - Primary Hepatic Epithelioid Angiomyolipoma Masquerading as Liver Abscess

Hepatic angiomyolipomas (AML) are rare mesenchymal tumours of which the epithelioid type is a rare type with malignant potential. We report a case of primary hepatic epithelioid angiomyolipoma masquerading as liver abscess. A 46-year-old man presented with a 5-day history of fever with epigastric pain and nausea. On the night of admission, his temperature spiked to 39°C, his blood pressure was 135/79, his heart rate 98, his liver function test revealed albumin 37 g/L, bilirubin 25 μmol/L, ALP 298 U/L, ALT 247 U/L, and AST 344 U/L. The clinical suspicion was hepatobiliary sepsis and intravenous ceftriaxone was commenced. CT of the abdomen showed an ill-defined hypodense focus in segment 4A/8 (4.5 × 3.5 cm) with a minimal fluid component implying a developing abscess or phlegmon. The images were reviewed by a radiologist and showed minimal fluid for percutaneous drainage. MRI of the liver was performed to further characterize the lesion and revealed a solid mass with nodular areas of arterial enhancement and washout, suspicious of neoplasm. Ultrasound-guided liver biopsy of the lesion was performed. Histology showed a histiocyte-rich epithelioid neoplasm consistent with the epithelioid variant of AML. Immunohistochemical staining was positive for human melanoma black 45, melan-A and cluster of differentiation 68. He successfully underwent liver resection of segment 4A/8 after 6 weeks of antibiotics. To our knowledge, this is the first reported case in the literature of primary hepatic epithelioid angiomyolipoma masquerading as liver abscess.

Differentiating Hepatic Epithelioid Angiomyolipoma From Hepatocellular Carcinoma and Focal Nodular Hyperplasia via Radiomics Models

Background: We conduct a study in developing and validating two radiomics-based models to preoperatively distinguish hepatic epithelioid angiomyolipoma (HEAML) from hepatic carcinoma (HCC) as well as focal nodular hyperplasia (FNH).

Methods: Totally, preoperative contrast-enhanced computed tomography (CT) data of 170 patients and preoperative contrast-enhanced magnetic resonance imaging (MRI) data of 137 patients were enrolled in this study. Quantitative texture features and wavelet features were extracted from the regions of interest (ROIs) of each patient imaging data. Then two radiomics signatures were constructed based on CT and MRI radiomics features, respectively, using the random forest (RF) algorithm. By integrating radiomics signatures with clinical characteristics, two radiomics-based fusion models were established through multivariate linear regression and 10-fold cross-validation. Finally, two diagnostic nomograms were built to facilitate the clinical application of the fusion models.

Results: The radiomics signatures based on the RF algorithm achieved the optimal predictive performance in both CT and MRI data. The area under the receiver operating characteristic curves (AUCs) reached 0.996, 0.879, 0.999, and 0.925 for the training as well as test cohort from CT and MRI data, respectively. Then, two fusion models simultaneously integrated clinical characteristics achieved average AUCs of 0.966 (CT data) and 0.971 (MRI data) with 10-fold cross-validation. Through decision curve analysis, the fusion models were proved to be excellent models to distinguish HEAML from HCC and FNH in comparison between the clinical models and radiomics signatures.

Conclusions: Two radiomics-based models derived from CT and MRI images, respectively, performed well in distinguishing HEAML from HCC and FNH and might be potential diagnostic tools to formulate individualized treatment strategies.

Hepatic Epithelioid Angiomyolipoma Treated with Laparoscopic Resection: Case Report and Review of the Literature

Hepatic angiomyolipoma is a rare primary liver tumor, with a radiographic appearance very similar to hepatocellular carcinoma. We present the case of a noncirrhotic patient with a liver tumor suspicious for HCC by imaging features. Liver biopsy demonstrated angiomyolipoma, and the patient successfully underwent a laparoscopic liver resection.

Two case reports and literature review for hepatic epithelioid angiomyolipoma: Pitfall of misdiagnosis

BACKGROUND

Hepatic epithelioid angiomyolipoma (HEAML) is a rare liver disease and is easily misdiagnosed. Enhanced recognition of HEAML is beneficial to the differential diagnosis of rare liver diseases.

CASE SUMMARY

We presented two cases of HEAML in Changzheng Hospital, Naval Medical University, and then collected and analyzed all reports about HEAML recorded in PubMed, MEDLINE, China Science Periodical Database, and VIP database from January 2000 to March 2018. A total of 409 cases of HEAML in 97 reports were collected, with a ratio of men to women of 1:4.84 and an age range from 12 years to 80 years (median 44 years). Among the patients with clinical symptoms mentioned, 61.93% (205/331) were asymptomatic, 34.74% (115/331) showed upper or right upper quadrant abdomen discomfort, while a few of them showed abdominal mass, gastrointestinal symptoms, low fever, or weight loss. The misdiagnosis rate of HEAML was as high as 40.34% (165/409) due to its nonspecific imaging findings. Most of the tumors were solitary and round in morphology, with clear boundaries. Ultrasound scan indicated low echo with internal nonuniformity and rich blood supply in most cases. Computer tomography/magnetic resonance imaging enhanced scan showed varied characteristics. The ratio of fast wash-in and fast wash-out, fast wash-in and slow wash-out, and delayed enhancement was roughly 4:5:1. A definite diagnosis of HEAML depended on the pathological findings of the epithelioid cells in lesions and the expression of human melanoma black 45, smooth muscle actin, melanoma antigen, and actin by immunohistochemical staining. HEAML had a relatively low malignant rate of 3.91%. However, surgical resection was the main treatment for HEAML, due to the difficulty diagnosing before operation.

CONCLUSION

HEAML is a rare and easily misdiagnosed disease, and it should be diagnosed carefully, taking into account clinical course, imaging, pathological ,and immunohistochemical findings.

Comparison of MRI Features of Epithelioid Hepatic Angiomyolipoma and Hepatocellular Carcinoma: Imaging Data From Two Centers

Introduction: Epithelioid hepatic angiomyolipoma (Epi-HAML) can easily be misdiagnosed as a malignant tumor such as hepatocellular carcinoma (HCC) because of the low-fat content on imaging. We analyzed and compared the magnetic resonance imaging (MRI) features of Epi-HAML and HCC, which would aid in disease diagnosis.

Methods: We included 30 pathologically confirmed patients with Epi-HAML and 80 with HCC, who underwent both MRI unenhanced scan and three-phase contrast-enhanced MRI scan. The clinical and MRI features of the two groups were summarized and analyzed.

Results: Epi-HAML showed significant differences compared to HCC group in terms of clinical features such as sex preference, age, concomitant diseases (hepatitis B and cirrhosis), and elevated plasma alpha-fetoprotein (AFP) (P < 0.001). In addition, there were statistically significant differences between both tumor types with regard to conventional MRI findings such as a solitary tumor (100 vs. 83.8%, P = 0.018), well-defined (93.3 vs. 71.3%, P = 0.027), mild hyperintensity (40.0 vs. 3.7%, P < 0.001) on DWI with high b-value, fat within the tumor (43.3 vs. 8.8%, P < 0.001), and rare necrosis (3.3 vs. 26.3%, P = 0.016). Besides, Epi-HAML displayed significant differences compared to HCC in terms of contrast-enhanced MRI characteristics such as draining hepatic vein (30.0 vs. 3.8%, P < 0.001), portal vein tumor thrombus (0 vs. 13.8%, P = 0.033), hypointensity at delayed phase (70.0 vs. 95%, P = 0.001), intra-tumor vessel at delayed phase (36.7 vs. 10.0%, P = 0.003), pseudocapsule (20.0 vs. 78.8%, P < 0.001), and prolonged enhancement (56.7 vs. 1.2%, P < 0.001).

Conclusion: Epi-HAML frequently occurs in middle-aged women and usually lacks characteristic clinical symptoms. Typically, Epi-HAML presents as an isolated and well-defined tumor with rich vasculature. Specific MRI features such as intra-tumor fat, intra-tumor vessel, draining hepatic vein, prolonged enhancement, and lack of capsule may contribute to a more confident diagnosis of Epi-HAML.

Hepatic epithelioid angiomyolipoma with renal metastasis: radiologic-pathologic correlation

Epithelioid angiomyolipoma (EAML) is a rare subtype of angiomyolipomas. Unlike the conventional angiomyolipomas, EAML often contains minimal fat which usually precludes prospective diagnosis on imaging. The imaging findings of EAML may overlap with other benign and malignant hepatic neoplasms. We report a hepatic epithelioid angiomyolipoma in a 47-year-old female which metastasized to the right kidney and recurred after resection in the liver. We analyze the imaging findings of EAML on ultrasound, computed tomography, positron emission tomography and magnetic resonance imaging. Correlation between the imaging and histopathologic findings is made. The estimated annual growth and doubling time of the primary hepatic EAML are calculated. To the best of our knowledge, this is the first published report of positron emission tomography–computed tomography findings and annual growth rate for hepatic EAML.

Epithelioid angiomyolipoma of the liver: a case report

Epithelioid angiomyolipoma (EAML) of liver is a rare neoplasm. Hepatic EAML is often misdiagnosed as other neoplasms such as hepatocellular carcinoma due to non-specific clinical and radiologic features. The morphologic features under microscope and immunohistochemistry staining profile are important in the diagnosis EAML. Here, we report a case of 52-year-old man who found 1.2 cm mass in liver by routine checkup. On the impression of hepatocellular carcinoma, lateral sectionectomy of the liver was done. Microscopically, the tumor is composed of predominant epithelioid cells with vascular component and foamy cells. These cells were positive for HMB45, MelanA, and smooth muscle actin and negative for epithelial membrane antigen. The final diagnosis was hepatic EAML.

Clinico-pathological correlation of hepatic angiomyolipoma: a series of 23 resection cases

BACKGROUND

Angiomyolipomas are rare neoplasms of mesenchymal origin and are derived from perivascular epithelioid cells. They usually develop in the kidney and rarely in the liver. Due to their rarity, most hepatic angiomyolipomas have been misinterpreted as hepatocellular carcinoma (HCC) or other hypervascular liver tumours on imaging studies. We aimed to assess the clinico-pathological correlation of hepatic angiomyolipoma.

METHODS

We identified 23 patients with hepatic angiomyolipoma through an institutional database search.

RESULTS

Of 5680 cases of primary liver tumours, 23 (0.4%) had angiomyolipomas (mean age, 43.6 ± 12.4 years; 16 female patients). Hepatitis B virus infection was noted in four patients, whereas a liver mass was incidentally detected on routine health screening in 13 patients. The preoperative diagnoses, before liver biopsy, included HCC in 14, angiomyolipoma in six, focal nodular hyperplasia in two and hepatic adenoma in one patient. Eventually, the preoperative diagnoses were changed to HCC in 12 and hepatic angiomyolipoma in 11 patients. The tumour size was 5.3 ± 4.6 cm, and 22 patients had a single tumour. All tumours exhibited positive findings for human melanoma black-45 and smooth muscle actin staining. During a follow-up period of 52.2 ± 23.7 months, none of the patients exhibited tumour recurrence or mortality.

CONCLUSIONS

Hepatic angiomyolipoma is a rare form of primary liver tumour and is often misdiagnosed as other hypervascular tumours. Although angiomyolipoma is benign in nature, it also has malignant potential; hence, resection is indicated if the tumour grows or malignancy cannot be excluded. Surgical resection is a definitive curative treatment of hepatic angiomyolipoma.

Hepatic epithelioid angiomyolipoma: clinical features and imaging findings of contrast-enhanced ultrasound and CT

AIM

To evaluate the clinical features and imaging findings of epithelioid angiomyolipoma (EAML) on contrast-enhanced ultrasound (CEUS) and contrast-enhanced computed tomography (CECT).

MATERIALS AND METHODS

During January 2006 to November 2015, six patients with histopathologically proven hepatic EAML were evaluated using both CECT and ultrasonography. Six patients underwent CEUS and four patients had CECT images. Patients' demographics, clinical presentations, laboratory test results, and imaging appearances were collected and analysed.

RESULTS

Six patients were female, and the mean age was 43.5 years. All hepatic EAMLs were solitary. None of patients had specific symptoms, and laboratory tests were normal in all patients. The maximal diameter of the lesions ranged from 3.1 to 6.5 cm (mean 4.4 cm). Baseline ultrasound revealed that 50% of hepatic EAMLs were hypo-echoic and 50% were mixed echoic. CEUS showed that 100% of the hepatic EAMLs displayed homogeneous hyperenhancement in the arterial phase and 67% (4/6) showed hypo-enhancement in the late phase. On CECT, 100% (4/4) of the neoplasms were significantly hyperenhanced in the arterial phase and washout in the portal phase. There was no recurrence or metastasis after a mean follow-up period of 11.8 months.

CONCLUSION

Hepatic EAML shows similar enhancement patterns to that of hepatocellular carcinoma. It should be considered as a possible differential diagnosis in female patients without viral hepatitis infection.