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

Avapritinib efficacy in primary hepatic neuroendocrine carcinoma with elevated PDGFRA expression: Insights from a PDX model study

BACKGROUND & AIMS

Primary Hepatic Neuroendocrine Carcinoma (PHNEC) is a rare and aggressive tumor with high recurrence rates. Surgical resection remains the only therapeutic strategy. The effectiveness of tyrosine kinase inhibitors (TKIs) for PHNEC remains unclear due to limited research.

METHODS

We employed immunohistochemical staining to diagnose PHNEC and assess the expression of eight tyrosine kinase receptors in tumor tissues, including VEGFRs, PDGFRA, EGFR, FGFRs et al. A patient-derived xenograft (PDX) model was established using PHNEC tumor tissues to test the efficacy of TKIs. PDX mice bearing tumors were treated with Avapritinib, an FDA-approved PDGFRA-targeting drug, at a daily oral dose of 10 mg/kg for 2 weeks.

RESULTS

Pathological analysis confirmed the diagnosis of PHNEC with positive expression of Neural cell adhesion molecule (NCAM/CD56), Synaptophysin (Syn), and Somatostatin receptor 2 (SSTR-2), and negative expression of Hep (Hepatocyte Paraffin 1), a biomarker for Hepatocellular carcinoma. Notably, PDGFRA was significantly overexpressed in PHNEC tumor tissues compared to other tyrosine kinases. Avapritinib treatment significantly reduced tumor growth in PDX mice by 73.9 % (p = 0.008). Additionally, Avapritinib treatment led to a marked decrease in PDGFRA and Ki-67 expression, suggesting that it inhibits tumor cell proliferation by suppressing PDGFRA.

CONCLUSION

Our findings suggest that PDGFRA is a potential therapeutic target for PHNEC, and its inhibition with Avapritinib may offer clinical benefits to patients with this rare malignancy.

Case Report: Primary hepatic neuroendocrine tumor: two cases report with literature review

Background & Aims

Primary hepatic neuroendocrine tumors (PHNETs) are rare malignant liver tumors that present diagnostic challenges owing to their rarity and absence of specific clinical features. This study aimed to investigate the characteristics of this rare liver tumor to enhance our understanding of the disease, improve diagnostic accuracy, and explore standardized diagnostic and treatment approaches.

Case description

During physical examination, two elderly women, aged 64 and 74 years, were found to have liver masses. 18F-FDG Positron Emission Tomography-Computed Tomography (18F-FDG PET-CT) and Ga68-DOTATATE PET-CT scans of both individuals revealed multiple liver masses that were initially suspected to be hepatic neuroendocrine tumors. Subsequent puncture pathology confirmed the diagnosis of neuroendocrine tumors. Furthermore, in Case 1, the tumor was also detected by 18F-FDG PET-CT in the lung, suggesting a metastatic tumor, in conjunction with liver immunohistochemistry and imaging findings. Laboratory tests revealed no significant abnormalities in liver function or autoimmune liver disease indicators, and there was no evidence of viral hepatitis infection. However, partial hepatectomy was not indicated for cases with distant metastasis or multiple space-occupying lesions. Individualized treatment approaches have been developed for such situations. A large portion of the tumor underwent Transarterial Embolization (TAE), and targeted combination chemotherapy or endocrine therapy was administered based on the pathological results. During regular follow-ups a 13 and 12 months, the tumor remained stable. The patients' quality of life was good, and their psychological well-being was healthy. They led active lifestyles, demonstrated a thorough understanding of their disease and its progression, and actively cooperated during the follow-up process.

Conclusion

Our findings suggest that a combination of serological, radiological, and immunohistochemical examinations can aid in the diagnosis of PHNET. In addition, we determined that TAE combined with drug therapy could be an effective method for controlling PHNET progression. Regular postoperative follow-ups are important for monitoring the prognosis and tumor progression status of patients with PHNET.

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.

Primary neuroendocrine tumors and primary neuroendocrine carcinomas of the liver: a proposal for a multidiscipline definition

Primary hepatic neuroendocrine tumors and primary hepatic neuroendocrine carcinomas are rare and pose challenges for both diagnosis and for determining whether the tumor is primary to the liver versus metastatic disease. The lack of a uniform definition for primary hepatic neuroendocrine neoplasms is also a limitation to understanding and treating these rare tumors. Recently, there have been significant histological advances in the diagnosis and classification of neuroendocrine tumors in general, as well as significant advances in imaging for neuroendocrine neoplasms, all of which are important for their treatment. This article presents a multiple disciplinary definition and proposed guidelines for diagnosing a neuroendocrine tumor/neuroendocrine carcinomas as being primary to the liver.

Developing a competing risk nomogram that predicts the survival of patients with a primary hepatic neuroendocrine tumor

Primary hepatic neuroendocrine tumor (PHNET) is rare liver cancer and related prognostic factors are unclear. The aim of this study was to analyze the prognostic risk factors of patients with PHNETs and establish an assessment model for prognosis. The clinical information of 539 patients with PHNETs who met the criteria for inclusion was extracted from the Surveillance, Epidemiology, and End Results (SEER) database. These patients were randomly assigned to the training (269 cases) and validation sets (270 cases). Prognostic factors in patients with PHNETs were screened using the Cox proportional regression model and Fine–Gray competing risk model. Based on the training set analysis using the Fine–Gray competing risk model, a nomogram was constructed to predict cumulative probabilities for PHNET-specific death. The performance of the nomogram was measured by using receiver operating characteristic curves, the concordance index (C-index), calibration curves, and decision curve analysis (DCA). No differences in clinical baseline characteristics between the training and validation sets were observed, and the Fine–Gray analysis showed that surgery and more than one primary malignancy were associated with a low cumulative probability of PHNET-specific death. The training set nomograms were well-calibrated and had good discriminative ability, and good agreement between predicted and observed survival was observed. Patients with PHNETs with a high-risk score had a significantly increased risk of PHNET-specific death and non-PHNET death. Surgical treatment and the number of primary malignancies were found to be independent protective factors for PHNETs. The competing risk nomogram has high accuracy in predicting disease-specific survival (DSS) for patients with PHNETs, which may help clinicians to develop individualized treatment strategies.

Molecular deciphering of primary liver neuroendocrine neoplasms confirms its distinct existence with foregut-like profile

Isolated hepatic localizations of neuroendocrine tumors (NETs) are generally considered as metastatic NETs of unknown primary but could correspond to primary hepatic NETs (PHNETs), a poorly explored entity. We aimed to describe the clinicopathological and molecular features of PHNETs and compare them with other primary NETs. We assembled a retrospective cohort of patients managed for hepatic localization of NET without extra-hepatic primary tumor after exhaustive clinical, imaging and immunohistochemical characterization. We performed whole-exome sequencing with mutational and copy number analysis. Transcriptomic profiles were compared to pancreatic (n=31), small-bowel (n=22) and lung (n=15) NETs using principal component analysis, unsupervised clustering and gene-set enrichment analysis. Among 27 screened patients, 16 had PHNET (solitary tumor in 63%, median size 11 cm, G2 NETs in 81%) following clinical and pathological review. DNA analyses showed "foregut-like" genomic profiles with frequent alterations in pathways of Fanconi DNA repair (75%), histone modifiers (58%), adherens junctions (58%) and cell cycle control (50%). The most frequently involved genes were KMT2A (58%), ATM (42%), CDH1, CDKN2C, FANCF and MEN1 (33% each). Transcriptomic analyses showed that PHNETs clustered closer to foregut (pancreatic, lung) NETs than to midgut (small-bowel) NETs, while remaining a distinct entity with specific profile. Assessment of potentially predictive biomarkers suggested efficacy of treatments usually active in foregut NETs. In conclusion, PHNETs display a foregut-like molecular profile distinct from other types of NETs, with recurrent molecular alterations. Upon exhaustive work-up to exclude unrecognized primary tumor, PHNETs should not be considered metastatic NETs from an unknown primary. This article is protected by copyright. All rights reserved.

Primary hepatic neuroendocrine carcinoma with colon adenoma: A case report with literature review

INTRODUCTION AND IMPORTANCE

Primary hepatic neuroendocrine tumors (PHNETs) are extremely rare, and the clinical symptoms, test results, and imaging characteristics are nonspecific in most patients; thus, it is difficult to differentiate from other liver masses before surgery. Histopathology and immunohistochemistry are the main basis for the diagnosis. PHNETs and colon tumors co-occur in a patient and are non-homologous, as reported in the English-language literature for the first time.

CASE PRESENTATION

We present a case of a 60-year-old woman with right hepatic lobe mass accidentally discovered on abdominal ultrasonography during a routine examination. Preoperative liver contrast-enhanced computed tomography suggested hepatocellular carcinoma; then, surgery were performed. Pathological results revealed a Grade 2 neuroendocrine tumor of the liver. In search of the primary tumor, upper and lower endoscopy of the GI tract was performed and revealed a mass in the ascending colon. Ascending colon cancer was considered; then, laparoscopic right hemicolectomy was performed. Pathological results suggested tubular villous adenoma of the ascending colon. The final diagnosis was not colon cancer with liver metastases but was PHNETs with colon adenoma.

CLINICAL DISCUSSION

PHNETs are rare cancers that are difficult to diagnose, requiring not only differentiation from other liver masses but also exclusion of metastases from extrahepatic sources. The pathological results play an important in making an accurate diagnosis.

CONCLUSION

Pathology, postoperative follow-up, and comprehensive imaging examinations are powerful tools in the diagnosis of PHNETs. Currently, surgery is the best treatment to achieve a potential cure and prolong the patient's survival.

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.

Efficacy of Chemotherapy versus Transcatheter Arterial Chemoembolization in Patients with Advanced Primary Hepatic Neuroendocrine Carcinoma and an Analysis of the Prognostic Factors: A Retrospective Study

Background

Primary hepatic neuroendocrine carcinoma (PHNEC) is a rare liver tumor, and there is no clear therapeutic recommendation for patients with advanced PHNEC. This study aims to compare the efficacy of platinum-based chemotherapy (etoposide combined with cisplatin/carboplatin, EP/EC) and transcatheter arterial chemoembolization (TACE) in patients with advanced PHNEC, and to evaluate the relevant prognostic factors.

Patients and Methods

The clinical data of 41 patients with advanced PHNEC from June 2014 to October 2019 were retrospectively reviewed.

Results

At a median follow-up time of 13.9 months, the median overall survival (OS) was 14.8 months in the EP/EC group and 12.2 months in the TACE group (P = 0.040). The median progression-free survival (PFS) was 4.4 months and 2.7 months in the EP/EC group and the TACE group, respectively (P = 0.005). No significant differences in the overall response rate and disease control rate were observed between the EP/EC group and the TACE group (26.1% vs 11.1%, P = 0.429; 73.9% vs 44.4%, P = 0.055, respectively). A univariate analysis indicated that the Eastern Cooperative Oncology Group performance status (ECOG PS), Ki-67, tumor number, and treatment options were prognostic factors for OS. A multivariate analysis further showed that ECOG PS (P < 0.001), Ki-67 (P = 0.003), and treatment options (P = 0.022) were independent prognostic factors for OS.

Conclusion

Ki-67, ECOG PS, and treatment options were the independent prognostic factors for OS in patients with advanced PHNEC. EP/EC may be a better choice for patients with advanced PHNEC.

Primary hepatic neuroendocrine tumor — 18F-fluorodeoxyglucose positron emission tomography/computed tomography findings: A case report

BACKGROUND

Primary hepatic neuroendocrine tumors (PHNETs) are rare hepatic tumors. Their diagnosis, which is based on radiological findings, is difficult.

CASE SUMMARY

We present a case of PHNET in a 79-year-old man with no clinical symptoms. Computed tomography (CT) and 2-Deoxy-2-[fluorine-18] fluorodeoxyglucose positron emission tomography/CT (¹⁸F-FDG PET/CT) were performed for further evaluation. A hypoattenuating mass with rim-like enhancement in segment 6 of the liver was detected on contrast-enhanced CT imaging. Increased uptake was also observed on ¹⁸F-FDG PET/CT. Histopathological and immunohistochemical examinations, which revealed a grade 2 neuroendocrine tumor (NET), confirmed the diagnosis.

CONCLUSION

Diagnosing PHNET is challenging, and must be distinguished from other liver tumors. Metastatic NETs should be excluded.