Primary hepatic neuroendocrine tumors: clinical characteristics and imaging features on contrast-enhanced ultrasound and computed tomography

Primary hepatic neuroendocrine neoplasms: imaging characteristics and misdiagnosis analysis

Objective

To analyze the CT and MR features of Primary hepatic neuroendocrine neoplasms (PHNENs) in order to enhance the diagnostic accuracy of this disease.

Methods

A retrospective analysis was conducted on patients diagnosed with hepatic neuroendocrine neoplasms, excluding other sites of origin through general examination and postoperative follow-up. The CT and MR signs were analyzed according to the 2018 version of Liver Imaging Reporting and Data System (LI-RADS), along with causes of misdiagnosis.

Results

Twelve patients, including 6 males and 6 females, were enrolled in this study. There was no significant increase in liver tumor markers among all cases. Most masses were multiple (9/12), exhibiting low attenuation on pre-contrast CT scans, T1-hypointense signal, T2-hyperintense signal, and restricted diffusion. The majority of these masses (7/10) demonstrated similar rim arterial phase hyper-enhancement as well as peripheral "washout" during venous portal phase and delayed phase imaging. Three cases had incomplete capsules while one case had a complete capsule. Cyst/necrosis was observed in 7 out of all cases following administration of contrast agent, with 5 mainly distributed in the periphery. All masses lacked fat, calcification, vascular or bile duct tumor thrombus formation.

Conclusion

The imaging findings associated with PHNENs possess certain specificity, often presenting as multiple masses within the liver accompanied by peripheral cyst/necrosis, similar rim arterial phase hyper-enhancement during venous portal phase and delayed phase imaging.

Comparison of primary hepatic neuroendocrine tumors and non-hepatitis B non-hepatitis C hepatocellular carcinoma on contrast-enhanced ultrasound

Objective

The purpose of this study was to compare the sonographic features of primary hepatic neuroendocrine tumors (PHNETs) to those of non-hepatitis B and non-hepatitis C hepatocellular carcinoma (NBNC-HCC) on contrast-enhanced ultrasound (CEUS).

Materials and methods

Fourteen patients with a mean age of 56.9 ± 12.2 (SD) years with histopathologically confirmed PHNET were included in the study. Twenty-eight patients with a mean age of 58.5 ± 10.4 years with histopathologically confirmed NBNC-HCC were randomly selected as the control group. The clinical data, conventional ultrasound and CEUS features were retrospectively analyzed between PHNET and NBNC-HCC.

Results

PHNET was more common in women (57.1%, 8/14 cases), and NBNC-HCC was more common in men (75.0%, 21/28) (P=0.040). No significant differences were observed in etiology, tumor marker, and liver function between the two group (P>0.05). Conventional ultrasound revealed that the tumor size of PHNET (10.1 ± 4.7 cm) was larger than that of NBNC-HCC (5.9 ± 3.8 cm) (P=0.006). NBNC-HCC was predominantly hypoechoic, while the echogenicity of PHNET varied (P=0.001). On CEUS, 57.1% (8/14) of PHNETs showed heterogeneous hyperenhancement, whereas 77.0% (21/28) of NBNC-HCC presented homogeneous hyperenhancement (P=0.015). Furthermore, 35.7% (5/14) of PHNETs showed early washout (onset of washout <60 s), which was significantly different from that of NBNC-HCC (3.7%, 1/28) (P=0.005).

Conclusion

CEUS is helpful in discriminating between PHNET and NBNC-HCC. PHNETs mainly present as a single mass with a large size (>10 cm) in the liver. The CEUS showed that most PHNETs exhibited heterogeneous enhancement in the arterial phase, washout in the portal venous and late phases and early washout being more likely than NBNC-HCC. However, more imaging features need to be evaluated in a larger sample.

Complete Response After Pre-Operative Transcatheter Arterial Chemoembolization for Unresectable Primary Hepatic Neuroendocrine Tumour: A Case Report and Literature Review

Background

Primary hepatic neuroendocrine tumours (PHNET) are extremely rare. Currently, no evidence-based guidelines are available for PHNET treatment, especially for unresectable tumours.

Case Presentation

We present the case of a 43-year-old man who was admitted to our hospital with complaints of backache for more than 1 month. The imaging examination showed a 5.5×5.3 cm lesion in the liver and no extrahepatic lesions, which was confirmed as a grade 2 PHNET by the pathological results and exclusion of non-hepatic origins. A multidisciplinary team (MDT) consultation revealed that the lesion was an unresectable primary hepatic neuroendocrine tumour (uPHNET) but could be potentially treated by conversion surgery. The patient was initially administered four cycles of chemotherapy with temozolomide, 5-fluorouracil, and ondansetron, and was evaluated as stable disease (SD) according to the Response Evaluation Criteria in Solid Tumours version 1.1 (RECIST 1.1). Because of the limited clinical benefit of chemotherapy, the patient subsequently underwent transcatheter arterial chemoembolisation (TACE) treatment, which reduced the tumour size and converted uPHNET to resectable tumours. A complete response (CR) was achieved after surgery, and the patient has been disease-free.

Conclusions

This case was reported by a patient with uPHNET who benefited from the pre-operative TACE, providing a potentially effective management strategy for refractory tumours.

Primary hepatic neuroendocrine neoplasm diagnosed by somatostatin receptor scintigraphy: A case report

BACKGROUND

Primary hepatic neuroendocrine neoplasm (NEN) is a rare condition, and it is difficult to differentiate between primary and metastatic hepatic NENs. Herein, we report a case of primary hepatic NEN that initially mimicked a hemangioma but showed a gradual increase in size on long-term careful observation.

CASE SUMMARY

A 47-year-old woman was incidentally diagnosed with a 12-mm liver mass, suspected to be a hemangioma. Since then, regular follow-up had been carried out. Ten years later, she was referred to our institute due to the tumor (located in segment 4) having increased to 20 mm. Several imaging studies depicted no apparent extrahepatic lesion. Positron emission tomography (PET)/computed tomography exhibited significant accumulation in the mass lesion, which made us consider the possibility of malignancy. Left hepatectomy was performed. The histopathological diagnosis was neuroendocrine tumor grade 2, with somatostatin receptor 2a/5 positivity. Postoperative somatostatin receptor scintigraphy (SRS) showed no other site, leading to the diagnosis of NEN of primary hepatic origin. The gradual growth of the hepatic NEN over 10 years suggested that it was likely to be a primary liver tumor.

CONCLUSION

In this case, positivity on PET and postoperative SRS may have helped determine whether the tumor was primary or metastatic.

Primary Hepatic Neuroendocrine Tumor Arising at a Young Age: Rare Case Report and Literature Review

Neuroendocrine tumors (NETs) are low-grade malignancies arising from neuroendocrine cells. Primary hepatic neuroendocrine tumors (PHNETs) are extremely rare and difficult to differentiate from other liver tumors, such as hepatocellular carcinoma (HCC) or cholangiocarcinoma. A 22-year-old male presented with intermittent abdominal pain. A preoperative imaging study revealed a 5.1cm-sized heterogeneously enhancing mass in S6 of the liver, suggesting HCC. Laparoscopic right hepatectomy was performed, and a well-demarcated brown solid mass was found. The pathology report revealed a neuroendocrine tumor of the liver. 18F-fluorodeoxyglucose-positron emission tomography/computed tomography was performed postoperatively to exclude extrahepatic lesions, and no lesions were found. This is a rare case of PHNET that developed at a young age and was misdiagnosed as HCC preoperatively. This suggests that PHNET should be considered one of the differential diagnoses when a non-specific enhanced hepatic tumor is found, even when the patient is young.

Hepatic Angiomyolipoma: Clinical Features and Imaging Findings of Quantitative Contrast-Enhanced Ultrasound Perfusion Analysis and Magnetic Resonance Imaging

OBJECTIVES

To investigate whether quantitative contrast-enhanced ultrasound (CEUS) analysis and magnetic resonance imaging (MRI) can differentiate hepatic angiomyolipoma (AML) from hepatocellular carcinoma (HCC) and hepatic epithelial angiomyolipoma (EAML) from nonepithelial AML.

METHODS

Retrospective analysis of 26 CEUS lesions pathologically confirmed as AML and 60 patients with confirmed HCC. Clinical and ultrasound (US) features of AML versus HCC and EAML versus nonepithelial AML were analyzed. Quantitative parameters, including arrival time, ascending slope, time to peak, peak intensity (PI), fall time (FT), and mean transit time (MTT), were analyzed. Diagnostic performance of MRI and CEUS was compared.

RESULTS

Angiomyolipoma was significantly different from HCC in US findings of solitary tumor (P < .001), well-defined border (P = .025), and hyperechogenicity (P < .001). Tumor types were significantly different in US findings of centripetal filling pattern (P < .001), less hypoenhancement in the CEUS delayed phase (P = .04), high PI (P = .007) and ascending slope (P = .006), and short FT (P = .001) and MTT (P < .05). The sensitivity and specificity of quantitative parameters were 61.5% to 96.2% and 55.0% to 71.7% (area under the curve, 0.642-0.773). An early draining vein and tumor vessels, intratumor fat, absence of pseudocapsules, mild signal intensity on diffusion-weighted imaging, and hypointensity in the MRI delayed phase were helpful for differentiation of AML from HCC (P < .05). The positive predictive values of CEUS and MRI were 46.3% to 100% and 42.9% to 75%, with no significant difference (P > .05). Epithelial AML was more likely to be hypoechoic with a centripetal filling pattern than nonepithelial AML (P < .05). The MTT and FT of EAML were shorter than those of nonepithelial AML (P < .05). The PI of EAML was significantly stronger than that of nonepithelial AML (P < .01). The sensitivity and specificity of quantitative parameters were 68.7% to 100.0% and 60.0% to 100.0% (area under the curve, 0.825-0.941). Less intratumor fat was helpful for differentiation of EAML from nonepithelial AML (P < .05). The positive predictive values of CEUS and MRI were 77.8% to 100% and 85.7%, with a significant difference (P < .05).

CONCLUSIONS

Quantitative CEUS findings could be valuable in differentiating EAML from HCC.

Clinical characteristics and outcome of primary hepatic neuroendocrine tumors after comprehensive therapy

BACKGROUND

Primary hepatic neuroendocrine tumors (PHNETs), a group of neuroendocrine neoplasms, are extremely rare. There are only few case reports about PHNETs in the literature. The lack of large samples and multicenter research results in poor diagnostic and therapeutic approaches.

AIM

To discuss the clinical characteristics, diagnosis, and treatment of PHNETs and risk factors related to survival.

METHODS

We retrospectively analyzed the clinical data, imaging features, immunohistochemistry data, and treatment efficacy of 40 patients who were pathologically diagnosed with PHNETs and admitted to The First Affiliated Hospital of Zhengzhou University from January 1, 2014 to November 15, 2019. Finally, survival analysis was performed to identify the risk factors for survival.

RESULTS

The main symptoms and signs included intermittent abdominal pain (19 patients, 47.5%) and bloating (8 patients, 20.0%). The positive rates of tested tumor markers were recorded as follows: Carbohydrate antigen 19-9 (CA19-9) (6 patients, 15.0%), CA72-4 (3 patients, 7.5%), carcinoembryonic antigen (7 patients, 17.5%), and alpha-fetoprotein (6 patients, 15.0%). Immunohistochemical staining results showed positivity for Syn in 38 (97.4%) of 39 patients, for chromogranin A in 17 (65.4%) of 26 patients, for CD56 in 35 (94.6%) of 37 patients, for AE1/AE3 in 28 (87.5%) of 32 patients, and for Ki-67 in all 40 (100.0%) patients. The overall survival rate was significantly related to the tumor grade, AE1/AE3, and Ki-67. No significant correlation was found between other parameters (age, gender, tumor number, tumor size, metastasis, and treatment) and overall survival.

CONCLUSION

Higher grade, negative AE1/AE3, and higher Ki-67 are associated with a worse survival rate. Kinds of treatment and other parameters have no significant influence on overall survival.

Primary hepatic neuroendocrine tumour masquerading as a giant haemangioma: an unusual presentation of a rare disease

Primary hepatic neuroendocrine tumour is an exceedingly rare entity. We hereby delineate the case of a 45-year-old Balti descent woman who hails from a land-locked village situated in the foothills of the Pakistani Himalayas. The patient presented to our medical centre with a hepatic mass. She underwent extensive diagnostic workup. The consistent findings of an abdominal CT scan, coupled with her clinical history, insinuated a preoperative diagnosis of atypical hepatic haemangioma. After a detailed discussion in a multidisciplinary meeting, a standard right hemihepatectomy was performed. She had an uneventful postoperative recovery and was discharged in stable condition after 1 week. Surprisingly, pathological examination and immunohistochemistry of the resected specimen divulged the diagnosis of a grade II primary hepatic neuroendocrine tumour. Her somatostatin-receptor scintigraphy and Gallium-68 DOTATATE positron emission tomography scan excluded residual hepatic or additional body lesions. Regular follow-ups over the past 4 years demonstrated unremarkable radiological findings with no recurrence to date.

Clinicopathological Characteristics and Survival Outcomes of Primary Hepatic Neuroendocrine Tumor: A Surveillance, Epidemiology, and End Results (SEER) Population-Based Study

BACKGROUND Primary hepatic neuroendocrine tumor (PHNET) is a rare primary liver tumor that remains poorly understood. Here, we explored the clinicopathological characteristics and survival outcomes of PHNET patients. MATERIAL AND METHODS PHNET patients diagnosed between 1988 and 2015 in the Surveillance, Epidemiology, and End Results (SEER) database were enrolled in the cohort. Kaplan-Meier analysis was used to determine the survival outcomes. Multivariable Cox regression models were used to identify the risk factors for overall survival (OS) and disease-specific survival (DSS). RESULTS A total of 291 PHNET patients from the SEER database met the inclusion criteria for analysis. The majority of the patients were female (53.6%), white (77.7%), and married (49.5%). The 1-, 3-, and 5-year OS were 57.1%, 39.4%, and 30.2%, and the 1-, 3-, and 5-year DSS rates were 61.3%, 44.3%, and 36.7%, respectively. Multivariate Cox regression models showed that older age, unmarried status, poor differentiated grade, and no tumor-directed surgery were independent risk factors for poor OS and DSS. CONCLUSIONS Older age, unmarried status, poor differentiated grade, and no tumor-directed surgery were associated with poorer prognosis of PHNET. Surgical resection is an effective and reliable treatment method for patients with PHNET.

Contrast-Enhanced Ultrasound Findings and Differential Diagnosis of Hepatic Epithelioid Angiomyolipoma Compared with Hepatocellular Carcinoma

Hepatic epithelioid angiomyolipoma (EAML) has malignant potential that can easily be misdiagnosed as hepatocellular carcinoma (HCC), but the treatment options of these conditions are different. This retrospective study investigated whether contrast-enhanced ultrasound (CEUS) can differentiate EAML from HCC. We included 24 patients with pathologically confirmed EAML and 36 patients with HCC who underwent pre-operative conventional ultrasound and CEUS. The conventional ultrasound and CEUS features of the two groups were analyzed. Time intensity curves (TICs) were analyzed for all lesions using quantitative perfusion analysis software. This study found that significant differences existed between the EAML and HCC groups in terms of clinical features such as sex, age, symptoms, alpha-fetoprotein and history of hepatitis B virus infection (p < 0.05). Tumor size, number, border and echogenicity on conventional ultrasound were significantly different between EAML and HCC (p < 0.05). Regarding CEUS, EAML was more likely to have a centripetal enhancement pattern than HCC (p < 0.05). The tumor enhancement degree in the delayed phase in CEUS was significantly different between EAML and HCC (p < 0.05). Quantitative analysis of CEUS parameters revealed that the wash-in area under the curve (AUC) was larger in EAML than in HCC (p < 0.05). Time to peak was significantly shorter in EAML than in HCC (p < 0.05). The peak intensity was significantly stronger in EAML than in HCC (p < 0.05). Regarding the diagnostic performance of CEUS parameters that showed statistical significance on univariate analysis, the sensitivity and specificity for distinguishing EAML from HCC was 66.7%-100.0% and 55.6%-91.7%, respectively. Overall, CEUS could be valuable in differentiating EAML from HCC. Specific features such as the centripetal filling and prolonged enhancement patterns on CEUS, higher peak intensity, bigger wash-in AUC and shorter time to peak on TICs may contribute to a more confirmative differential diagnosis of EAML.

Analysis of B-ultrasound and contrast-enhanced ultrasound characteristics of different hepatic neuroendocrine neoplasm

BACKGROUND

Hepatic neuroendocrine neoplasm (hNEN) is a highly heterogeneous tumor. The exact identification of the source and malignant degree of hNEN is important. However, there is a lack of information regarding diagnosis of hNEN with imaging. In addition, no studies have compared the imaging between hNEN and hepatocellular carcinoma (HCC) and among different sources and malignant degrees of hNEN.

AIM

To compare the ultrasound characteristics between hNEN and HCC and among different sources and malignant degrees of hNEN.

METHODS

A total of 55 patients with hNEN were recruited and defined as the hNEN group. Among them, 35 cases of hNET were defined as the hNET group. Twenty cases of hepatic neuroendocrine carcinoma (hNEC) were defined as the hNEC group. Among the 55 lesions, 29 were transferred from the pancreas, 20 were from the gastrointestinal tract, and six were from other sites. In total, 55 patients with HCC were recruited and defined as the HCC group. The characteristic differences of B-mode ultrasound and contrast-enhanced ultrasound (CEUS) between hNEN and HCC and among different sources and malignant degrees of hNEN were compared.

RESULTS

In the hNEN group, the proportions of multiple liver lesions, unclear borders, and high echo lesions were higher than those in the HCC group. The proportions of non-uniform echo and peripheral acoustic halo were lower than those in the HCC group (P < 0.05). The washout to iso-enhancement time and washout to hypo-enhancement time were lower than those in the HCC group (P < 0.05). The characteristics of B-ultrasound and CEUS among different sources of hNEN were similar, and the differences were not statistically significant (P > 0.05). B-mode ultrasound characteristics of hNET and hNEC were similar. The proportions of low enhancement at portal venous phase, non-uniform enhancement forms, and combined tumor vasculature in the hNEC group were larger than those in the hNEN group (P < 0.05).

CONCLUSION

Compared with HCC, hNEN showed multiple intrahepatic lesions, uniform high echo, uniform high enhancement at arterial phase, and rapid washout. Low enhancement at portal venous phase, overall non-uniform enhancement form, and the proportion of combined tumor vasculature in hNEC were larger than those in hNET.

Primary hepatic neuroendocrine tumours-Case series of a rare malignancy

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Primary hepatic neuroendocrine tumours are rare.

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Liver enzymes and tumour markers are often normal.

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Radiological imaging may mimic other hypervascular liver tumours.

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Surgical resection is the only curative treatment for localised disease.

Introduction

Primary hepatic neuroendocrine tumours (PHNET) were first described by Edmondson et al. in 1958 and are rare, accounting for only 0.3% of all neuroendocrine tumours. Only several hundred cases have been reported.

Presentation of case

We present two cases. The first is a 65-year-old asymptomatic male referred with a liver lesion on ultrasound performed to investigate a mildly elevated Alanine Aminotransferase (ALT). Hepatitis serology and tumour markers were normal. He had an unremarkable colonoscopy and gastroscopy. CT and MRI revealed a single liver lesion adjacent to the gallbladder suspicious for malignancy. He underwent a segment IVb/V liver resection. Histology was consistent with a 65 mm grade 2 PHNET. Subsequent Dotatate PET/CT scans have been normal at 5 years. The second is an asymptomatic 73-year-old male referred with fluctuating hepatic enzymes and a history of alcohol overuse. Imaging revealed a suspicious lesion in segment III of the liver. He underwent a left lateral liver resection. Histology revealed an 18 mm grade 1 PHNET. A subsequent Dotatate PET/CT was normal with no new disease at six months.

Discussion

PHNET, albeit rare are in the differential diagnosis for primary hepatic malignancies. Tumour markers are usually normal and radiological imaging can mimic other hypervascular hepatic tumours. Surgery is the only curative treatment for localised disease to date.

Conclusion

PHNET needs to be considered in asymptomatic patients with hypervascular hepatic lesions. More research is required before other adjunct treatment options can be suggested.

Primary hepatic neuroendocrine tumor case with a preoperative course of 26 years: A case report and literature review

Primary hepatic neuroendocrine tumor (PHNET) is an extremely rare liver tumor. Patients often have no clinical symptoms or have only non-specific symptoms, such as abdominal pain and abdominal mass. The clinical manifestations, disease development, treatment methods, and treatment outcomes of PHNET vary greatly among cases. Here we report a case of PHNET with a confirmed 26-year survival before surgery. The patient was a 56-year-old female. A large right hepatic mass was detected when the patient was 30 years old. The tumor could not be removed during exploratory laparotomy, and constriction of the right hepatic artery and biopsy were conducted. Pathological results indicated a diagnosis of benign tumor, but a confirmed diagnosis was not reached. Twenty-six years after the patient had been living with the tumor, she sought treatment again because of tumor progression. After systematic evaluation of the resectability, the tumor was resected. Based on the examination results of the gastrointestinal tract and lungs, intraoperative examination results, pathological findings, and long-term follow-up results, the diagnosis of PHNET was confirmed. This case represents the longest reported survival time for a PHNET patient before removal of the tumor.

Analysis of the clinicopathological features and prognostic factors of primary hepatic neuroendocrine tumors

Neuroendocrine tumors (NETs) of the gastrointestinal tract often spread to the liver, while primary hepatic NETs (PHNETs), first described by Edmondson in 1958, are very rare. The majority of existing reports regarding PHNETs have small sample sizes, and the clinicopathological characteristics and prognostic factors are still unclear. The aim of the present study was to analyze the clinicopathological features and explore the prognostic factors of PHNETs. From March 2012 to March 2017, 28 cases of PHNETs were retrospectively evaluated to analyze the clinicopathological features and explore the prognostic factors of PHNETs. The 28 PHNETs patients were males (n=15) and females (n=13) aged between 32 and 76 years (mean=53 years). Among them, 16 patients had clinical symptoms. The remaining 12 patients had no obvious clinical symptoms, only hepatoncus was observed during physical examination. Single-factor analysis showed that carbohydrate antigen 125 (CA125), alanine aminotransferase (ALT), aspartate aminotransferase (AST), hemoglobin (HB), Ki-67 positive index (PI), surgical treatment and pathological grading were correlated to PHNET prognosis (P<0.05); multifactor analysis revealed that Ki-67 PI was associated with the prognosis (P<0.05). Thus, the prognosis of PHNETs may be effectively predicted using the indexes of CA125, ALT, AST, HB, Ki-67 PI, pathological grading and surgical treatment. Pathological classification of grade 3, high expression of Ki-67 PI, abnormal elevation of CA125, abnormalities of ALT and AST, anemia and lack of radical operation indicated a poor prognosis. High expression of Ki-67 PI was an independent prognostic factor for PHNETs.

Role of contrast-enhanced ultrasound to define prognosis and predict response to biotherapy in pancreatic neuroendocrine tumors

PURPOSE

The incidence of neuroendocrine tumors (NETs) is progressively increasing. Most cases arise from the digestive system, where ileum, rectum and pancreas represent the commonest site of origin. Liver metastases are frequently detected at diagnosis or during the follow-up. Contrast-enhanced ultrasound (CEUS) is used in patients with pancreatic NETs (P-NETs) and liver metastases from P-NET but its role has not been standardized. The aim of this retrospective study was to investigate CEUS in patients with P-NETs and liver metastases from P-NET both as prognostic factor and predictor of response to therapy with somatostatin analogues (SSAs).

METHODS

CEUS was performed at the diagnosis of NET and 3, 6 and 12 months after the beginning of SSAs. CEUS pattern was compared with contrast-enhanced computed tomography (CT) pattern.

RESULTS

There was a significant association between CEUS and CT pattern (X ² = 79.0; p < 0.0001). A significant association was found between CEUS pattern and Ki-67 index (X ² = 24.6; p < 0.0001). The hypervascular homogeneous CEUS typical pattern was associated with low tumor grading (G1 or G2) (X ² = 24.0; p < 0.0001). CEUS pattern changed from hypervascular homogeneous in baseline to hypovascular/hypervascular inhomogeneous after SSA therapy, with a significant association between tumor response at CT scan and appearance of hypervascular inhomogeneous pattern at CEUS evaluation (6 months: X ² = 57.0; p < 0.0001; 12 months: X ² = 49.8; p < 0.0001).

CONCLUSIONS

In patients with P-NET, CEUS pattern correlates with tumor grading, being homogeneous in G1-G2 but not in G3 tumors. After therapy with SSAs, CEUS is predictive of response to SSAs. These findings seem to support a role of CEUS as prognostic and predictive factor of response.

Primary Hepatic Neuroendocrine Tumor with Unusual Thyroid Follicular-Like Morphologic Characteristics

We describe a primary hepatic neuroendocrine tumor of a 57-year-old Thai woman who presented in 2004 with a suspicious mass in the left hepatic lobe. She underwent left hepatectomy for the 10.5-cm mass, called intermediate grade neuroendocrine carcinoma of unknown origin, likely metastatic. The tumor recurred in 2007, then called recurrent primary hepatic neuroendocrine tumor (PHNET), and the patient underwent liver transplant. Because of similarity between the neuroendocrine tumor and a thyroid tumor-specifically, follicular-like characteristics-immunohistochemical stains for thyroglobulin, TTF1, and calcitonin were performed. However, all were negative. All imaging studies revealed no evidence of a primary lesion other than the liver mass. In 2008, the patient's liver transplant failed because of ischemic cholangiopathy, and she underwent a second liver transplant. Seven years later, in 2015, she presented with metastatic neuroendocrine tumor of intermediate grade to the lung, consistent with metastatic PHNET. She underwent left upper-lobe wedge resection to remove the tumor. The patient is alive with no evidence of disease at 13 years after initial diagnosis. This rare variant of PHNET had thyroid-like morphologic characteristics but there is no evidence of primary thyroid tumor or thyroid markers in the primary and recurrent hepatic tumors and lung metastasis.