Multi-slice computed tomography manifestations of hepatic epithelioid angiomyolipoma

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.

Hepatic epithelioid angiomyolipoma: magnetic resonance imaging characteristics

PURPOSE

The aim of the study was to analyze MR imaging features of hepatic epithelioid angiomyolipoma (HEAML).

METHODS

This study included 113 patients with 122 pathologically confirmed HEAML who underwent enhanced MRI scanning before partial hepatectomy. MR images were retrospectively reviewed and correlated with pathological findings.

RESULTS

The mean age of 113 patients was 48.12 ± 11.77 years old, and the male to female ratio was 1:3.35 with 87 females (76.99%). 107 (94.69%) patients presented as single tumor, and 96 patients (84.96%) were asymptomatic. 122 HEAML lesions were diagnosed pathologically in 113 patients, with the average of 4.47 ± 3.26 cm. 109 lesions (89.34%) and 108 lesions (88.52%) showed regular and well-defined boundary. On T1WI, 121 lesions (99.18%) mainly presented hypointensity. On T2WI, 118 lesions (96.72%) and 109 lesions (89.34%) mainly showed hyperintensity and heterogeneous signals. Most of the lesions (97.46%) showed hyperintensity on DWI. 118 lesions (96.72%) manifested as severe hyperenhancement and 106 lesions (86.89%) showed heterogeneity during the arterial phase. As for the lesion enhancement pattern, 73 lesions (59.84%) presented as persistent enhancement, 37 lesions (30.33%) as wash out, 8 lesions (6.56%) as degressive enhancement, and 4 lesions (3.28%) as poor blood supply. Additionally, 96 lesions (78.69%) with intra-tumor vessels and 85 lesions (69.67%) with outer rim were confirmed during the delayed phase.

CONCLUSION

At enhanced MRI, hypointensity on T1WI, hyperintensity and heterogeneous signals on T2WI, hyperintensity on DWI, little or no fat component, heterogenous hyperenhancement, persistent enhancement, intra-tumor vessels, and outer rim would be helpful to diagnose HEAML.

Primary hepatic epithelioid angiomyolipoma: a small case series

BACKGROUND

Hepatic epithelioid angiomyolipomas (HEAMLs) are rare and usually arise in case reports, and thus, we aimed to study the clinicopathological features, treatment and prognosis of these lesions.

METHODS

We identified patients from institutional database with HEAMLs and retrospectively collected clinical data.

RESULTS

Of 12 patients, 10 were females, and the median age was 49 years. A liver mass was found on chance upon routine health screening in nine patients. Imaging features included clear border (9/12), internal heterogeneity (8/12), arterial enhancement (12/12), fat (5/12), intra-tumour vessel (3/12), draining hepatic vein (2/12) and pseudocapsule (1/12). The preoperative diagnoses contained HEAML (n = 5), hepatocellular carcinoma (n = 6), and hepatic cystadenocarcinoma (n = 1). All cases had received surgery and obtained a negative margin. All specimens showed positive findings for HMB-45 and Melan A. No tumour recurrence or mortality was described with a mean follow-up time of 23.5 months.

CONCLUSIONS

HEAML is a low potential malignancy tumour that frequently appears in middle-aged females. It has nonspecific symptoms and may present special imaging features including intra-tumour vessel, early draining hepatic vein and lack of a pseudo capsule. The lesion is confirmed by pathological and immunohistochemical findings. Surgery and subsequent long-term follow-up are the most appropriate management approaches.

Baseline and contrast-enhanced ultrasound features of hepatic epithelioid angiomyolipoma

BACKGROUND

Recurrence or metastasis after surgery had been reported in hepatic epithelioid angiomylipoma (epi-AML). Most hepatic epi-AMLs were misdiagnosed with hepatocellular carcinoma or other hepatic tumors before surgery.

OBJECTIVE

To describe the baseline and contrast-enhanced ultrasound (CEUS) features of hepatic epi-AMLs and to explore the potential ultrasonic features for prognosis.

METHODS

The retrospective study enrolled 67 patients (56 females, 11 males) with 67 pathologically confirmed hepatic epi-AML lesions. All the lesions were examined by baseline ultrasound and 42 lesions were examined using CEUS with SonoVue (Bracco, Milan, Italy) before surgery.

RESULTS

Baseline ultrasound features of hepatic epi-AMLs included heterogeneous echo (86.6%), well-defined border (68.7%), hypoecho (64.2%), regular morphology (62.7%), peripheral-tumor arc-shaped or ring-like vessels (53.7%), and low value of resistive index (0.51±0.08). CEUS features of hepatic epi-AMLs included arterial phase hyper-enhancement with smooth and well-defined margin (100%), peripheral-tumor ring-like vessels (57.1%), and intra-tumor vessels (52.4%). Some CEUS features, including arterial phase heterogeneously tortuous filling, intra-tumor vessels and peripheral-tumor ring-like vessels were more commonly found in hepatic epi-AMLs of uncertain malignant potential/malignant than in benign hepatic epi-AMLs (p <  0.05).

CONCLUSIONS

Baseline ultrasound and CEUS features may be useful in diagnosis of hepatic epi-AML, and some CEUS features may be indicative of its malignant potential.

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.

Contrast-enhanced sonographic appearances of two primary hepatic epithelioid angiomyolipomas

Epithelioid hepatic angiomyolipoma (Epi-HAML) is a rare hepatic tumor frequently misdiagnosed as hepatocellular carcinoma (HCC). Unlike conventional angiomyolipoma (AML), Epi-HAML contains minimal amount of adipose tissue, which is a radiological distinguishing feature between AML and HCC. Two patients were referred for management of incidentally found hepatic lesions confirmed to be Epi-HAML on post-resection tissue analysis. CT and MRI findings were suggestive of HCC. Contrast-enhanced ultrasound demonstrated intratumoral shunting, a feeding artery, and early draining hepatic vein. These findings should alert radiologists to the possibility of Epi-HAML. Furthermore, these features may be better assessed by contrast-enhanced ultrasound due to its superior dynamic temporal resolution.

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: 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.

Primary hepatic epithelioid angiomyolipoma: A malignant potential tumor which should be recognized

AIM: To improve the clinical diagnosis and recognition of hepatic epithelioid angiomyolipoma (HEAML).

METHODS: Four cases of primary HEAML were confirmed based on the pathology archive system in our hospital from January 2009 to November 2015. The general state, clinical symptoms, imaging manifestations, histological results and immunohistochemistry of these patients were retrospectively reviewed and analyzed. Studies of HEAML published in the last 15 years were collected from PubMed and MEDLINE to summarize the clinical symptoms, imaging characteristics, pathological features and management of HEAML.

RESULTS: Four cases of primary HEAML were retrieved from our archives. These included three female patients and one male patient, with a mean age of 41.8 ± 11.5 years (ranging from 31 to 56 years). The mean tumor size was 7.3 ± 5.5 cm (ranging from 3.0 to 15 cm). In the contrast-enhanced imaging, the tumor was obviously enhanced in the arterial phase, but enhanced continuously or exhibited a slow-density masse during the venous and delayed phases. Histologically, the tumors mainly consisted of epithelioid cells that comprised approximately 95% of the total neoplastic mass. Although no metastases occurred in our patients, pathological studies revealed necrosis, mitotic figures and liver invasion in two patients, which indicates aggressive behavior. Immunohistochemical staining revealed that human melanoma black 45 (HMB-45) and Melan-A were positive in 4 cases. We only identified 81 cases with primary HEAML, including our present patients, from 26 articles available from PubMed and MEDLINE. The majority of the papers were published as case reports. Only 5 (5/75, 6%) cases were associated with tuberous sclerosis complex (TSC). More than half (35/66) were discovered incidentally upon physical examination. Approximately 65% (22/34) of the patients were misdiagnosed with HCC or other tumors before surgery. Approximately 10% (8/81) of the patients with HEAML had recurrence or metastasis after surgery, which was a very high and alarming rate.

CONCLUSION: HEAML is a very rare primary hepatic tumor that is often misdiagnosed before surgery. Patients should be followed closely after surgery because of its malignant potential.

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

Hepatic epithelioid angiomyolipoma (EAML) is a rare type of hepatic tumor. Due to a lack of adequate understanding about this tumor, hepatic EAML is often misdiagnosed as other diseases with similar clinical characteristics such as hepatic cancer. In the present study, 3 cases of hepatic EAML are reported, and the main clinicopathological features of this disease are presented, based on a literature search that included articles published in English between February 2000 and September 2014. A total of 24 hepatic EAML cases were considered, of which, 17 were females and 4 presented multiple liver lesions. Among the patients with single lesions, 2 underwent surgery and relapsed after 5 months and 9 years, respectively. Immunohistochemical staining was positive for human melanoma black-45 in the present 3 cases. The aim of the present study was to focus the attention of clinicians on this type of hepatic tumor in order to improve its diagnosis and treatment.