Prognostic factors in gastrointestinal endocrine tumors

Current Management of Neuroendocrine Tumour Liver Metastases

PURPOSE OF REVIEW

This article aims to illustrate the current state of investigations and management of liver metastases in patients with Neuroendocrine Neoplasms. Neuroendocrine tumours (NETs) are rising in incidence globally and have become the second most prevalent gastrointestinal malignancy in UK and USA. Frequently, patients have metastatic disease at time of presentation. The liver is the most common site of metastases for gastro-enteropancreatic NETs. Characterisation of liver metastases with imaging is important to ensure disease is not under-staged.

RECENT FINDINGS

Magnetic resonance imaging and positron emission tomography are now becoming standard of care for imaging liver metastases. There is an increasing armamentarium of therapies available for management of NETs and loco-regional therapy for liver metastases. The data supporting surgical and loco-regional therapy is reviewed with focus on role of liver transplantation. It is important to use appropriate imaging and classification of NET liver metastases. It is key that decisions regarding approach to treatment is undertaken in a multidisciplinary team and that individualised approaches are considered for management of patients with metastatic NETs.

Quarter Century PET/Computed Tomography Transformation of Oncology: Neuroendocrine Tumors

Significant improvement in molecular imaging and theranostics in the management of neuroendocrine tumors (NETs) has been made in the last few decades. Somatostatin receptor-targeted PET imaging outperforms conventional, planar, and single-photon emission computed tomography imaging and is indicated in the evaluation of these patients when available, resulting in a significant impact on staging, treatment response assessment, and restaging of these patients. Radionuclide therapy can have an impact on patient outcome in metastatic disease when not many treatment options are available.

Comparison of 68Ga-DOTATATE Positron Emmited Tomography/Computed Tomography and Gadoxetic Acid-Enhanced Magnetic Resonance Imaging for the Detection of Liver Metastases from Well-Differentiated Neuroendocrine Tumors

This study aimed to compare the detection of neuroendocrine tumor liver metastases (NLMs) in hepatobiliary-specific contrast-enhanced MRI (pMR) versus 68Ga-DOTATATE PET/CT (DT-PET). This retrospective study cohort included 30 patients with well-differentiated neuroendocrine tumors who underwent both DT-PET and pMR. Two readers independently assessed NLMs count, SUVmax on DT-PET, and signal characteristics on pMR. A consensus review by two additional readers resolved discrepancies between the modalities. Results showed concordance between DT-PET and pMR NLM count in 14/30 patients (47%). pMR identified more NLMs in 12/30 patients (40%), of which 4 patients showed multiple deposits on pMR but only 0-1 lesions on DT-PET. DT-PET detected more in 4/30 patients (13%). Overall, pMR detected more metastases than DT-PET (p = 0.01). Excluding the four outliers, there was excellent agreement between the two methods (ICC: 0.945, 95%CI: 0.930, 0.958). Notably, pMR had a higher NLM detection rate than DT-PET, with correlations found between lesion size on pMR and DT-PET detectability, as well as diffusion restriction on pMR and SUVmax on DT-PET. In conclusion, in consecutive patients with well-differentiated NETs, the detection rate of NLM is higher with pMR than with DT-PET. However, when excluding patients whose tumors do not overexpress somatostatin receptors (13% of the cohort), high concordance in the detection of NLM is observed between DT PET and pMR.

Simultaneous laparoscopic liver metastasectomy and intersphincteric resection for neuroendocrine tumor of the rectum by natural orifice specimen extraction surgery

Neuroendocrine tumors (NET) are relatively uncommon rectal neoplasms, and the liver is the most common site of distant metastasis. Simultaneous liver and colorectal resections by minimally invasive surgery and natural orifice specimen extraction are gaining popularity, reducing morbidity. We describe a case of rectal NET with liver metastasis operated simultaneously by laparoscopy with both specimens extracted via the anal canal. Transanal or transvaginal natural orifice specimen extraction surgery for suitable cases is underutilized and only isolated case reports for simultaneous resections exist.

Neuroendocrine Tumor Therapy Response Assessment

Peptide receptor radionuclide therapy has become an integral part of management of neuroendocrine neoplasms. Gallium-68- and lutetium-177-labeled somatostatin receptor analogues have replaced yttrium-90- and 111-indium-based tracers. Several newer targeted therapies are also being used in clinical and research settings. It is imperative to accurately evaluate the response to these agents. The characteristics of NENs and the response patterns of the targeted therapies make response assessment in this group challenging. This article provides an overview of the strengths and weaknesses of the various biomarkers available for response assessment.

Volumetric Enhancing Tumor Burden at CT to Predict Survival Outcomes in Patients with Neuroendocrine Liver Metastases after Intra-arterial Treatment

Purpose To investigate whether liver enhancing tumor burden (LETB) assessed at contrast-enhanced CT indicates early response and helps predict survival outcomes in patients with multifocal neuroendocrine liver metastases (NELM) after intra-arterial treatment. Materials and Methods This retrospective study included patients with NELM who underwent intra-arterial treatment with transarterial embolization (TAE) or chemoembolization (TACE) between April 2006 and December 2018. Tumor response in treated NELM was evaluated by using the Response Evaluation Criteria in Solid Tumors (RECIST) and modified RECIST (mRECIST). LETB was measured as attenuation 2 SDs greater than that of a region of interest in the nontumoral liver parenchyma. Overall survival (OS); time to unTA(C)Eable progression, defined as the time from the initial treatment until the time when intra-arterial treatments were considered technically unfeasible, either not recommended by the multidisciplinary tumor board or until death; and hepatic and whole-body progression-free survival (PFS) were evaluated using multivariable Cox proportional hazards analyses, the Kaplan-Meier method, and log-rank test. Results The study included 119 patients (mean age, 60 years ± 11 [SD]; 61 men) who underwent 161 treatments. A median LETB change of -25.8% best discriminated OS (83 months in responders vs 51 months in nonresponders; P = .02) and whole-body PFS (18 vs 8 months, respectively; P < .001). A -10% LETB change best discriminated time to unTA(C)Eable progression (32 months in responders vs 12 months in nonresponders; P < .001) and hepatic PFS (18 vs 8 months, respectively; P < .001). LETB change remained independently associated with improved OS (hazard ratio [HR], 0.56), time to unTA(C)Eable progression (HR, 0.44), hepatic PFS (HR, 0.42), and whole-body PFS (HR, 0.47) on multivariable analysis. Neither RECIST nor mRECIST helped predict patient outcome. Conclusion Response according to LETB change helped predict survival outcomes in patients with NELM after intra-arterial treatments, with better discrimination than RECIST and mRECIST. Keywords: CT, Chemoembolization, Embolization, Abdomen/GI, Liver Supplemental material is available for this article. © RSNA, 2023.

Neuroendocrine hepatic metastatic disease: the surgeon's perspective

Neuroendocrine tumors are a rare subset of tumors that are increasing in incidence over the last 4 decades. These tumors occur along the gastrointestinal tract and bronchopulmonary tree and frequently metastasize. Up to 90% of patients with gastroenteropancreatic neuroendocrine tumors develop liver metastases (NeLM) during their clinical course. The development of NeLM and their appropriate management has a profound impact on patient morbidity and mortality. Workup of NeLM involves biopsy to define tumor grade, cross-sectional imaging to delineate the distribution and number of metastases, and hormonal studies to determine tumor functionality. Depending on these three factors, a combination of cytoreductive surgery, liver-directed therapies, and medical management-with cytostatic and cytotoxic chemotherapies, is utilized. The multidisciplinary management of patients with NeLM should carefully consider all these factors.

Preoperative assessment of microvessel density in nonfunctioning pancreatic neuroendocrine tumors (NF-PanNETs)

BACKGROUND

Hypervascularization is a typical feature of pancreatic neuroendocrine tumors, and it frequently allows their recognition at imaging studies. However, the density of microvessels in pancreatic neuroendocrine tumors changes according to their biological behavior, and a low microvessel density is associated with higher disease aggressiveness. The primary aim was to investigate the relationship between microvessel density and aggressiveness of nonfunctioning pancreatic neuroendocrine tumors. The secondary aim was to evaluate the ability of contrast-enhanced computed tomography and contrast-enhanced endoscopic ultrasound in predicting tumor microvessel density.

METHODS

The patients who underwent surgery for nonfunctioning pancreatic neuroendocrine tumors (n = 66) with an available preoperative contrast-enhanced computed tomography (n = 39) and/or contrast-enhanced endoscopic ultrasound (n = 37) performed at San Raffaele Hospital (2016-2020) were included. The tumor vascularization was assessed by CD-34 staining, contrast-enhanced computed tomography, and contrast-enhanced endoscopic ultrasound. Median microvessel density (165 microvessels/mm²) was chosen as the cutoff to define low microvessel density and high microvessel density.

RESULTS

The patients with a low microvessel density showed a significantly higher frequency of nodal metastases (P = .026), G2-G3 tumors (P = .022), and death domain-associated protein/α-thalassemia/mental retardation syndrome X-linked loss (P = .011) compared to patients with high microvessel density. The contrast-enhanced computed tomography tumor density in the arterial phase was significantly higher in patients with high microvessel density compared to those with low microvessel density (P = .016). The patients with a low microvessel density showed a significantly higher frequency of contrast-enhanced endoscopic ultrasound arterial hypoenhancement (P = .042) and late washout (P = .034). Contrast-enhanced computed tomography arterial hypoenhancement (P = .007) and contrast-enhanced endoscopic ultrasound late washout (P = .048) independently predicted a low microvessel density in the patients who underwent contrast-enhanced computed tomography and contrast-enhanced endoscopic ultrasound, respectively.

CONCLUSION

A low microvessel density represents a marker of aggressiveness in the patients with nonfunctioning pancreatic neuroendocrine tumors. Contrast-enhanced computed tomography and contrast-enhanced endoscopic ultrasound are reliable and easily available tools for preoperative assessment of microvessel density.

The Potential Prognostic Value of Dual-Imaging PET Parameters Based on 18F-FDG and 18F-OC for Neuroendocrine Neoplasms

Background

To identify parameters based on dual-imaging ¹⁸F-AlF-NOTA-octreotide (¹⁸F-OC) and 18-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET) for predicting the prognosis of neuroendocrine neoplasms (NENs).

Materials and Methods

Sixty-six patients (age: mean ± standard deviation (SD): 51.8 ± 11.8 years) who underwent both ¹⁸F-OC and ¹⁸F-FDG PET/CT imaging were enrolled in our retrospective study. The following PET parameters were measured: the maximum standardized uptake value (SUV_max) and the volumetric parameters—¹⁸F-OC SSR-derived tumor volume (TV) and somatostatin receptor expression (SRE, TV multiplied by the mean standardized uptake value (SUV_mean)) and the ¹⁸F-FDG-derived multiple tumor volume (MTV) and tumor lesion glycolysis (TLG). The NETPET grade based on dual-imaging PET images was assessed. Progression-free survival (PFS) was set as an endpoint. Univariate and multivariate survival analyses were performed for PET parameters and clinical tumor data.

Results

In the univariate survival analyses of clinical information, PFS was significantly associated with age (>45.5 vs ≤45.5, years, P < 0.034) and the presence of bone metastases (P = 0.04). Higher values for the ¹⁸F-FDG and ¹⁸F-OC volumetric parameters and the NETPET grade were adverse factors for PFS according to the dual-imaging PET parameters. In the multivariate survival analysis, the NETPET grade and SRE were predictors of PFS in NEN patients.

Conclusion

The NETPET grade is a potential noninvasive prognostic biomarker for NENs.

Use of MRI and Ga-68 DOTATATE for the detection of neuroendocrine liver metastases

PURPOSE

To compare detection rates of NET liver metastases of MRI and Ga-68-DOTATATE PET/CT to provide more clarity when selecting diagnostic imaging tests for NET staging.

METHODS

In this IRB-approved single-institution retrospective study, all patients with pathology-proven NET who underwent Ga-68-DOTATATE and MRI scans within 8 weeks of each other (3/2017-2/2020) were reviewed. Number of metastases for each patient on diffusion-weighted imaging (DWI), dynamic contrast-enhanced (DCE) MRI, and Ga-68 DOTATATE were recorded by two blinded radiologists, followed by consensus review with two separate blinded readers for MRI and nuclear medicine. Per-lesion and -modality scoring at each lesion location were then performed in consensus. Per-patient linear regression was performed comparing MRI and Ga-68 DOTATATE detection rates for each reader and in consensus, and per-lesion-matched pair difference means were used to compare detection frequency between modalities.

RESULTS

32 patients (mean age 59 years, 59.4% male) and 90 liver metastases were analyzed. Intraclass coefficients (ICC) [95% CI] between the two readers were 0.97 [0.95, 0.99], 0.89 [0.82, 0.94], and 0.98 [0.97, 0.99] for Ga-68 DOTATATE, DWI, and DCE, respectively. Matched per-lesion mean differences were + 0.17 ± 0.07 (p = 0.01) and + 0.22 ± 0.06 (p =  < 0.001) for DWI versus Ga-68 DOTATATE and DCE vs Ga-68 DOTATATE, respectively, favoring MRI. Case-based linear regressions estimate that DWI and DCE detect 1.28 [1.07, 1.49] and 1.33 [1.12, 1.54] lesions, respectively, for each one detected on Ga-68 DOTATATE.

CONCLUSION

MRI detects more hepatic NET metastasis in comparison to Ga-68 DOTATATE. Liver MRI should be performed in concert with Ga-68 DOTATATE in NET staging.

A Nomogram to Predict Individual Survival of Patients with Liver-Limited Metastases from Gastroenteropancreatic Neuroendocrine Neoplasms: A US Population-Based Cohort Analysis and Chinese Multicenter Cohort Validation Study

INTRODUCTION

Although gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) with liver metastasis encompass a wide variety of clinical conditions with various prognosis, no statistical model for predicting the prognosis of these patients has been established. We sought to establish a more elaborative and individualized nomogram to predict survival of patients with liver-limited metastatic GEP-NENs. In addition, this nomogram was validated by both the Surveillance, Epidemiology, and End Results (SEER) database and a Chinese multicenter cohort.

METHODS

Patients diagnosed with GEP-NENs with liver-limited metastasis between 2010 and 2016 were identified from the SEER database. Kaplan-Meier survival analysis was performed to analyze survival outcomes. A nomogram was established based on the independent prognostic variables identified from univariate and multivariate Cox regression analyses. The nomogram was evaluated in both an internal validation SEER dataset and an external validation dataset composed of patients from the Chinese multicenter cohort.

RESULTS

A total of 1,474 patients from the SEER database and 192 patients from the multicenter cohort were included. Age, tumor size, differentiation, primary tumor resection, and liver metastasis resection were identified as independent prognostic factors by univariate and multivariate Cox analyses and were verified by Kaplan-Meier survival analysis (all p < 0.0001). A nomogram was developed and validated by calibration curves and areas under the curve of the external validation cohort, which showed good consistency and veracity in predicting overall survival.

CONCLUSION

A nomogram was developed for the first time to predict the survival of patients with liver-limited metastases from GEP-NENs. Both internal and external validation demonstrated excellent discrimination and calibration of our nomogram. Based on this prognostic model, clinicians could develop more personalized treatment strategies and surveillance protocols.

Effects of tumor origins and therapeutic options on the prognosis of hepatic neuroendocrine tumors: A retrospective study

Hepatic neuroendocrine tumors (HNETs) are uncommon neoplasms that can be subdivided into 2 types: primary and metastatic HNETs. Due to its rarity, heterogeneity and complexity, the diagnosis, treatment modalities and prognosis are still controversial.This retrospective study reviewed the effects of tumor origins and therapeutic options on the prognosis of gastroenteropancreatic neuroendocrine tumors with liver metastasis (GEP-NETLM) and primary hepatic neuroendocrine tumors (PHNETs), providing additional evidence for clinicians evaluating patients.HNETs consisted of PHNETs and GEP-NETLM. GEP-NETLM (76.2%, 112/147) was more common, which was mainly manifested as multiple lesions in both lobes of the liver. PHNETs were relatively rare (23.8%, 35/147) and were mainly single lesion located in the right lobe of the liver. In patients with GEP-NETLM, primary tumor resection could prolong survival (P = .044). As the most widely used treatment method, systematic therapy alone could not achieve a satisfactory survival. However, the combination with hepatectomy or liver-directed therapy improved the prognosis (P = .023). As the main treatment, patients with PHNETs treated with local therapy could achieve a better prognosis (P = .049). Compared with PHNETs patients, GEP-NETLM patients with higher ki-67 index showed higher mortality and poorer prognosis (P = .006).Therefore, patients with PHNETs can be distinguished from GEP-NETLM by comprehensive imaging examinations and long-term follow-ups. The choice of appropriate treatment strategies can improve the prognosis of HNETs patients.

Simultaneous multi-slice accelerated diffusion-weighted imaging with higher spatial resolution for patients with liver metastases from neuroendocrine tumours

AIM

To evaluate the imaging characteristics of simultaneous multi-slice (SMS) accelerated diffusion-weighted imaging (DWI) with decreased section thickness, with and without motion correction, in comparison to conventional DWI (cDWI) for the detection of lesions in patients with neuroendocrine tumour (NET) liver metastases.

MATERIALS AND METHODS

Fifteen patients with NET liver metastases underwent cDWI (section thickness [SL]=4 mm) and SMS-DWI (SL=2 mm). Non-linear motion-corrected (Moco)-SMS-DWI was generated in addition to the original series. Qualitative imaging characteristics (five-point Likert scale), the number of high signal lesions, and the detectability and delineation of lesions were evaluated and compared using the Friedman and the Dunn-Bonferroni tests. The test-retest variability (TRV) of the cDWI and SMS-DWI techniques was investigated among 11 healthy volunteers who underwent cDWI (SL=4 mm) and SMS-DWI (SL=4 mm) twice. The Friedman and the Dunn-Bonferroni post-hoc tests were used to compare the mean apparent diffusion coefficient (ADC) and the TRV in different liver regions between the three series.

RESULTS

Moco-SMS-DWI demonstrated significantly superior overall image quality (p<0.001) with significantly fewer artefacts (p=0.003) than cDWI. The number of lesions detected by cDWI, SMS-DWI, and Moco-SMS-DWI were 348, 504, and 523, respectively. The detectability and delineation of the lesions and the ADC values were significantly higher on the SMS-DWI and Moco-SMS-DWI images than on the cDWI images (all p<0.001). Moco-SMS-DWI showed significantly higher TRV than cDWI in regions near the liver edge (p=0.018).

CONCLUSIONS

SMS-DWI achieves higher spatial resolution than cDWI within the same acquisition time, detects more lesions, and provides better lesion delineation. By applying motion correction, the TRV of DWI could be enhanced in regions near the liver edge.

Impact of a Prior Nonpancreatic Malignancy on Survival Outcomes of Patients With Stage IV Pancreatic Neuroendocrine Tumor: A Population-Based and Propensity Score Matching Study

OBJECTIVE

The aim of the study was to investigate the impact of a previous nonpancreatic malignancy on the survival outcomes in patients with a stage IV pancreatic neuroendocrine tumor (PanNET).

METHODS

The Surveillance, Epidemiology, and End Results database was reviewed, and patients diagnosed with a stage IV PanNET between 2004 and 2015 were selected. Patients were divided into 2 groups according to the presence or absence of a previous nonpancreatic malignancy. Clinicopathological characteristics and survival outcomes were compared.

RESULTS

A total of 1582 patients with stage IV PanNET were identified, of whom 116 (7.3%) had a prior malignancy. Prostate (33.62%), breast (17.24%), and gastrointestinal (12.07%) malignancies were the most common. Most prior malignancies (84.48%) were localized and regional. Patients with intervals of 36 months or less, 36 to 60 months, 60 to 120 months, and more than 120 months account for 25.86%, 14.66%, 31.03%, and 28.45% of all cases, respectively. Before and after propensity score matching, there was no significant difference detected regarding survival outcomes.

CONCLUSIONS

Stage IV PanNET patients with a history of a prior cancer had comparable survival outcomes with patients without such history. These patients could be candidates for clinical trials if otherwise appropriate, and aggressive and potentially curative therapies should be offered.

Management of Appendiceal Neuroendocrine Tumors: Metastatic Potential of Small Tumors

BACKGROUND

Appendiceal neuroendocrine tumors (ANETs) are rare neoplasms usually discovered incidentally during appendectomy. ANETs < 2 cm were thought to have no metastatic potential, and this dogma has driven management. Our aim is to evaluate the metastatic potential of ANETs < 2 cm.

PATIENTS AND METHODS

A retrospective review was performed in a series of patients with ANETs who presented to our tertiary referral center from 1998 to 2019. Demographics, tumor characteristics, treatment, and clinical outcomes were evaluated.

RESULTS

In total, 114 patients were included. Median follow-up was 3.3 years (range, 21 days-15 years). At last follow-up, 34 (30%) patients had positive regional lymph nodes and 20 (18%) patients had metastatic disease. Of the 20 patients with metastatic disease, 11 (55%) had primary ANETs < 2 cm. Patient age > 40 years at diagnosis and ANETs with serosal invasion, lymphovascular invasion, intermediate tumor grade, or positive lymph nodes were features significantly more likely to present with metastatic disease. We found no difference in the rate of lymph node positivity, metastatic disease, or overall survival when patients were stratified by tumor size or type of resection (appendectomy vs. right hemicolectomy). On multivariate analysis, patients with metastatic disease at diagnosis had worse overall survival (HR = 24.4, p = 0.008).

CONCLUSIONS

In our cohort, tumor size was not a significant risk factor for metastatic disease or worse outcome as many patients with ANETs < 2 cm developed metastatic disease. Appendectomy alone was sufficient surgical management for most ANETs. Patients with risk factors for metastatic disease, regardless of primary ANET size, should be evaluated thoroughly and counseled for further management and surveillance.

Epithelial-Mesenchymal Transition Proteins in Neuroendocrine Neoplasms: Differential Immunohistochemical Expression in Different Sites and Correlation with Clinico-Pathological Features

The first step leading to metastasis, or for the acquisition of local invasiveness, involves changes in the phenotype of neoplastic cells in the primary tumor. The epithelial–mesenchymal transition (EMT) is a process that determines the acquisition of a form and a transcriptional program that are characteristic of mesenchymal cells, in epithelial cells. The factors involved in this process are E-cadherin and N-cadherin adhesion proteins and some transcription factors such as Slug and Twist. EMT is a site-specific mechanism that is also active in embryogenesis—embryonic cells are affected if invested in certain points, probably due to the signals emanating from the cells or groups of surrounding cells. It is known that neuroendocrine neoplasms have a biological behavior that differs in grading, staging, and site. The aim of our study was to investigate the immunohistochemical expression of EMT factors (Twist, Slug, and E-cadherin) in the neuroendocrine neoplasms of the gastrointestinal tract, the pancreas, and lungs, in 65 cases retrieved from the archives of the Department of Pathology, of three hospitals. The immunoscores were compared in each site and correlated with the clinico-pathological parameters. Statistical evaluation revealed an association between the higher Twist immunoscore and higher grading (p value < 0.0001) and staging (p value = 0.0055). Slug was detected only in pancreatic cases where its reduced expression was associated with a higher grading (p value = 0.0033). This data could be of diagnostic utility in the case of metastases from neuroendocrine neoplasm, to define the site of the primitive tumor when the traditional immunohistochemical panel is not sufficient. In summary, our results indicated, first that the EMT is also an active process in neuroendocrine neoplasms. To the best of our knowledge, this was the first study that evaluated the expression of EMT factors in neuroendocrine neoplasms of different districts.

Primary site surgery for elderly patients with distant metastatic pancreatic neuroendocrine tumor: to do or not to do?

Objective

To investigate the effect of primary site surgery (PSS) on elderly patients (≥65 years) with pancreatic neuroendocrine tumor (pNET) distant metastasis.

Patients and methods

We reviewed Surveillance Epidemiology and the End Results database for elderly patients with distant pNET from 1973 to 2015. The variables and survival outcomes of patients with PSS were compared with that of patients with no PSS. After propensity score matching, the survival outcome was compared again between the two groups. Multivariable Cox proportional hazard model was used to identify variables associated with cancer-specific and overall survival. Four sub-groups were divided according to the age and differentiation: 1) age 65–74 years+ well or moderately differentiated; 2) age ≥75 years+ well or moderately differentiated; 3) age 65–74 years+ poorly differentiated or undifferentiated; and 4) age ≥75 years+ poorly differentiated or undifferentiated. Cancer-specific survival was compared between the patients with and without PSS in the above each group.

Results

A total of 210 elderly patients with distant pNET were finally confirmed. Of which, 148 patients did not undergo PSS, while 62 patients underwent PSS. Being female (p=0.049), locating on body/tail of pancreas (p=0.006), and well or moderately differentiated (p=0.032) were more likely received PSS. The patients underwent PSS had better survival outcomes both before and after propensity score matching. Multivariable Cox proportional hazard analysis proves PSS and higher histological grade to be protective and risk factors. PSS may improve cancer specific survival in patients of group 1), and no improvement was observed in patients of the other three sub-groups.

Conclusion

Not all elderly patients with pNET distant metastasis could benefit from PSS. Patients aged 65–74 years with well or moderately differentiated may benefit from primary lesion surgery, but should be evaluated carefully. Prospective randomized controlled trials are worth performing.

Liver transplantation in patients with liver metastases from neuroendocrine tumors

The prevalence of metastatic disease in neuroendocrine tumors (NETs) is very high (60-80%) and cancer-related death among these patients is generally due to metastatic disease. Numerous treatment options for cure and disease control have been investigated for patients with neuroendocrine liver metastases (NELM). Despite the success of liver directed therapy on slowing tumor progression and palliating symptoms, the chance of being cured by liver resection is 40-50% and only roughly 20% of patients have potentially resectable disease. As such, there has been interest in liver transplantation (LT) as a potentially curative option for patients with unresectable disease. Several criteria have been proposed in order to balance long-term outcomes of patients with NELM and the problem of organ shortage including the Milan-NET criteria, the UNOS criteria and the ENETS guidelines. In the most representative studies, recurrence rate after LT has ranged from 30% to 60% with a 5-year OS ranging from 50% to 97%. This large variability is due to the retrospective nature of the studies available, which used different inclusion criteria. As such, outcomes and the prognostic factors associated with LT for NELM warrant further investigation.

[Oligometastases of neuroendocrine tumors-extent of surgery]

Neuroendocrine tumors (NETs) are rare neoplasms, which represent complex challenges in diagnosis and treatment. Even in the metastatic stage there are important differences in the type of tumor in comparison to gastrointestinal and pancreatic adenocarcinomas. Therefore, the disease courses are substantially different depending on the grade of differentiation. Even in the metastatic stage the 5‑year survival rates of G1 tumors is up to 83%. Approximately 20% of small intestine NETs additionally show hormone activity, which can compromise survival and the quality of life. For individual treatment decisions the special tumor biology of these tumors must be taken into consideration more so than for other tumor entities. Surgery always becomes important for these tumors when a R0 resection appears possible. Oligometastasis of the liver and the lymph drainage system can be meaningfully approached by surgical treatment. In selected patients with an isolated liver involvement, a liver transplantation can be considered; however, even tumor debulking can lead to improvement in the quality of life and survival, especially for hormone active tumors with a carcinoid syndrome which cannot be conservatively controlled. The aim of this review is to present the value of surgical treatment options in the case of (oligo)metastasized NETs.

Minimally Invasive Management of Secondary Liver Cancer

Laparoscopic liver surgery for secondary liver cancer is increasing. The most common indications are colorectal cancer liver metastases followed by adenocarcinoma metastases from other solid organs, such as breast, pancreatic neuroendocrine, and other gastrointestinal tract cancers. This article provides a comprehensive review of crucial concepts when managing secondary liver cancer minimally invasively, a summary of the up-to-date literature, and a discussion of the development of the application of this technique over time.

Metastatic neuroendocrine tumors of the gastrointestinal tract and pancreas: A surgeon's plea to centering attention on the liver

Over 50% of patients with gastroenteropancreatic neuroendocrine tumors (GEP-NETs) have stage IV disease at presentation and the most likely organ to be affected by metastases is the liver. Hepatic involvement and hepatic tumor burden is a key prognostic factor affecting survival of these patients and 80% eventually die of liver failure due to tumor dissemination within the liver. This commentary explores the efficacy and limitations of systemic treatments in patients with GEP-NETs and liver metastases. Landmark randomized trials using systemic therapies including sandostatin (PROMID), lanreotide (CLARINET), everolimus (RADIANT 3 and 4), sunitinib and Peptide Receptor Radionuclide Therapy (NETTER-1) have not shown efficacy in reducing liver tumor burden in patients with stage IV GEP-NETs with liver metastases as outlined in this review. Although often overlooked, surgical debulking has been associated with a significant survival advantage in large retrospective studies and in our opinion should remain an important therapeutic option for patients with stage IV GEP-NETs and liver metastases.

Follow-Up for Resected Gastroenteropancreatic Neuroendocrine Tumours: A Practice Survey of the Commonwealth Neuroendocrine Tumour Collaboration (CommNETS) and the North American Neuroendocrine Tumor Society (NANETS)

OBJECTIVES

There is no consensus regarding optimal follow-up in resected gastroenteropancreatic neuroendocrine tumours (NETs). We aimed to perform a practice survey to ascertain follow-up patterns by health care practitioners and highlight areas of variation that may benefit from further quantitative research.

METHODS

A Web-based survey targeted at NET health care providers in Australia, New Zealand, Canada, and the USA was developed by a steering committee of medical oncologists and a research methodologist. Thirty-seven questions elicited information regarding adherence to guidelines, the influence of risk factors on follow-up, and the frequency and choice of modality in follow-up.

RESULTS

There were 163 respondents: 59 from Australia, 25 from New Zealand, 46 from Canada, and 33 from the USA (50% medical oncology, 23% surgery, 13% nuclear medicine, and 15% other). Thirty-eight percent of the respondents were "very familiar" with the NCCN NET guidelines, 33% with the ENETS guidelines, and 17% with the ESMO guidelines; however, only 15, 27, and 10%, respectively, found them "very useful"; 63% reported not using guidelines at their institution. The commonest investigations used were CT scans (66%) and chromogranin A (86%). The US respondents were more likely to follow patients up past 5 years, and the Australian respondents utilized more functional and less cross-sectional imaging. When poor prognostic factors were introduced, the respondents recommended more visits and tests.

CONCLUSIONS

This large international survey highlights variation in current follow-up practices not well addressed by the current guidelines. More quantitative research is required to inform the development of evidence-based guidelines tailored to the pattern of recurrence in NETs.

Early Recurrence of Neuroendocrine Liver Metastasis After Curative Hepatectomy: Risk Factors, Prognosis, and Treatment

BACKGROUND

Early tumor recurrence after curative resection typically indicates a poor prognosis. The objective of the current study was to investigate the risk factors, treatment, and prognosis of early recurrence of neuroendocrine tumor (NET) liver metastasis (NELM) after hepatic resection.

METHODS

A total of 481 patients who underwent curative-intent resection for NELM were identified from a multi-institutional database. Data on clinicopathological characteristics, intraoperative details, and outcomes were documented. The optimal cutoff value to differentiate early and late recurrence was determined to be 3 years based on linear regression.

RESULTS

With a median follow-up of 60 months, 223 (46.4%) patients developed a recurrence, including 158 (70.9%) early and 65 (29.1%) late recurrences. On multivariable analysis, pancreatic NET, primary tumor lymph node metastasis, and a microscopic positive surgical margin were independent risk factors for early intrahepatic recurrence. While recurrence patterns and treatments were comparable among patients with early and late recurrences, early recurrence was associated with worse disease-specific survival than late recurrences (10-year NELM-specific survival, 44.5 vs 75.8%, p < 0.001). Among the 34 (21.5%) patients who underwent curative treatment for early recurrence, post-recurrence disease-specific survival was better than non-curatively treated patients (10-year NELM-specific survival, 54.2 vs 26.3%, p = 0.028), yet similar to patients with late recurrences treated with curative intent (10-year NELM-specific survival, 54.2 vs 37.4%, p = 0.519).

CONCLUSIONS

Early recurrence after surgery for NELM was associated with the pancreatic type, primary lymph node metastasis, and extrahepatic disease. Re-treatment with curative intent prolonged survival after recurrence, and therefore, operative intervention even for early recurrences of NELM should be considered.

A nation-wide retrospective epidemiological study of gastroenteropancreatic neuroendocrine neoplasms in china

BACKGROUND

Representative data on the gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) in Asian patients is rare, especially in China. This study aims to create a GEP-NENs profile of Chinese patients.

METHODS

This was a hospital-based, nation-wide, and multi-center 10-year (2001-2010) retrospective study which collected GEP-NEN patients' information in tertiary referral hospitals. All 2010 inpatient GEP-NEN cases with confirmed pathology in the selected hospitals were included. The primary GEP-NEN sites were measured and the epidemiological and clinical information of each tumor site were compared.

RESULTS

The most common primary sites for GEP-NEN were the pancreas (31.5%) and rectum (29.6%), followed by the cardia (11.6%) and body (15.4%) of stomach. Small intestinal and colonic NENs took up a relatively small proportion of all patients. Pancreatic and rectal NENs, rather than cardiac and gastric body NENs, tended to be found in younger (P<0.001), female (P<0.001), urban (P<0.001) residents with a higher education level (P=0.032) and were also diagnosed at earlier stage (P<0.001) and lower grade (P<0.001). Surgery remained the primary treatment method in all groups.

CONCLUSIONS

More studies on the commonality and heterogeneity of GEP-NENs are warranted to improve diagnosis efficiencies and treatment outcomes.

Timing of disease occurrence and hepatic resection on long-term outcome of patients with neuroendocrine liver metastasis

BACKGROUND AND OBJECTIVES

The objective of the study was to evaluate the impact of timing of disease occurrence and hepatic resection on long-term outcome of neuroendocrine liver metastasis (NELM).

METHODS

A total of 420 patients undergoing curative-intent resection for NELM were identified from a multi-institutional database. Date of primary resection, NELM detection and resection, intraoperative details, disease-specific (DSS), and recurrence-free survival (RFS) were obtained.

RESULTS

A total of 243 (57.9%) patients had synchronous NELM, while 177 (42.1%) developed metachronous NELM. On propensity score matching (PSM), patients with synchronous versus metachronous NELM had comparable DSS (10-year DSS, 76.2% vs 85.9%, P = 0.105), yet a worse RFS (10-year RFS, 34.1% vs 59.8%, P = 0.008). DSS and RFS were comparable regardless of operative approach (simultaneous vs staged, both P > 0.1). Among patients who developed metachronous NELM, no difference in long-term outcomes were identified between early (≤2 years, n = 102, 57.6%) and late (>2 years, n = 68, 42.4%) disease on PSM (both P > 0.1).

CONCLUSIONS

Patients with synchronous NELM had a higher risk of tumor recurrence after hepatic resection versus patients with metachronous disease. The time to development of metachronous NELM did not affect long-term outcome. Curative-intent hepatic resection should be considered for patients who develop NELM regardless of the timing of disease presentation.

An elevated serum alkaline phosphatase level in hepatic metastases of grade 1 and 2 gastrointestinal neuroendocrine tumors is unusual and of prognostic value

Background

In our clinical practice we have observed that despite a high hepatic metastatic tumor burden, serum alkaline phosphatase (AP) levels are frequently normal in cases of metastatic neuroendocrine tumor (NET).

Patients and methods

We retrospectively reviewed the records of patients with grade 1 and 2 NETs with liver metastases but without bone metastases seen at our institution in 2013. In total, 49 patients were included (22 female), with a median age of 60 years (range: 28 to 84 years). The primary tumors were located in the duodenum/pancreas (n = 29), small bowel (n = 17) or colon/rectum (n = 3); 10 cases were grade 1 and 39 grade 2. Hepatic involvement was bulky, with more than 10 lesions in 23 patients and a tumor burden above 10% of the liver volume in 26 patients.

Results

Serum AP levels were elevated (≥ upper limit of normal (ULN)) in 16 patients. In multiparametric analysis, elevated serum AP levels were not associated with the primary site, grade, or number or volume of metastases. In multiparametric analysis, progression-free survival was only correlated with grade (p = 0.010) and AP level (p = 0.017).

Conclusions

Serum AP levels are frequently normal in liver metastases from NET, even in the event of a major tumor burden, and the serum AP level can be of prognostic value.

Immunohistochemical Markers as Predictors of Histopathologic Response and Prognosis in Rectal Cancer Treated with Preoperative Adjuvant Therapy: State of the Art

We explain the state of the art of the immunohistochemical markers of response in rectal cancers treated with neoadjuvant medical therapies and its implication with prognosis. Neoadjuvant chemoradiotherapy is widely used to improve the outcome of patients with locally advanced rectal cancer, and the evaluation of the effects of medical therapy is to date based on histomorphological examination by applying four grading systems of response to therapy (tumor regression grade (TRG)). The need to identify immunohistochemical markers that could ensure a better assessment of response and possibly provide additional prognostic information has emerged. We identified p53, p27kip1, Ki67, matrix metalloprotease-9, survivin, Ki67 proliferative index, CD133, COX2, CD44v6, thymidylate synthase, thymidine phosphorylase, and dihydropyrimidine dehydrogenase as the most common markers studied in literature to date, and we explained their prognostic potential and their implications in the evaluation of the response to preoperative therapies in rectal cancers.

Neuroendocrine liver metastasis: The chance to be cured after liver surgery

BACKGROUND AND OBJECTIVE

Neuroendocrine liver metastasis tumors (NELM) are a heterogeneous group of neoplasms with varied histologic features and a wide range of clinical behaviors. We aimed to identify the fraction of patients cured after liver surgery for NELM.

METHODS

Cure fraction models were used to analyze 376 patients who underwent hepatectomy with curative intent for NELM.

RESULTS

The median and 5-year disease-free survival (DFS) were 4.5 years and 46%, respectively. The probability of being cured from NELM by liver surgery was 44%; the time to cure was 5.1 years. In a multivariable cure model, type of neuroendocrine tumor (NET), grade of tumor differentiation, and rate of liver involvement resulted as independent predictors of cure. The cure fraction for patients with well differentiated NELM from gastrointestinal NET or a functional pancreatic NET, and with <50% of liver-involvement was 95%. Patients who had moderately/poorly differentiated NELM from a non-functional pancreatic NET, and with <50% of liver-involvement was 43%. In the presence of all the three unfavorable prognostic factors (nonfunctional PNET, liver involvement >50%, moderately/poorly differentiation), the cure fraction was 8%.

CONCLUSIONS

Statistical cure after surgery for NELM is possible, and allow for a more accurate prediction of long-term outcome among patients with NELM undergoing liver resection.

A Novel Nomogram to Predict the Prognosis of Patients Undergoing Liver Resection for Neuroendocrine Liver Metastasis: an Analysis of the Italian Neuroendocrine Liver Metastasis Database

Even though surgery remains the only potentially curative option for patients with neuroendocrine liver metastases, the factors determining a patient's prognosis following hepatectomy are poorly understood. Using a multicentric database including patients who underwent hepatectomy for NELMs at seven tertiary referral hepato-biliary-pancreatic centers between January 1990 and December 2014, we sought to identify the predictors of survival and develop a clinical tool to predict patient's prognosis after liver resection for NELMs. The median age of the 238 patients included in the study was 61.9 years (interquartile range 51.5-70.1) and 55.9 % (n = 133) of patients were men. The number of NELMs (hazard ratio = 1.05), tumor size (HR = 1.01), and Ki-67 index (HR = 1.07) were the predictors of overall survival. These variables were used to develop a nomogram able to predict survival. According to the predicted 5-year OS, patients were divided into three different risk classes: 19.3, 55.5, and 25.2 % of patients were in low (>80 % predicted 5-year OS), medium (40-80 % predicted 5-year OS), and high (<40 % predicted 5-year OS) risk classes. The 10-year OS was 97.0, 55.9, and 20.0 % in the low, medium, and high-risk classes, respectively (p < 0.001). We developed a novel nomogram that accurately (c-index >70 %) staged and predicted the prognosis of patients undergoing liver resection for NELMs.

The Long-Term Benefit of Liver Transplantation for Hepatic Metastases From Neuroendocrine Tumors

Selection criteria and benefit of liver transplantation for hepatic metastases from neuroendocrine tumors (NETs) remain uncertain. Eighty-eight consecutive patients with metastatic NETs eligible for liver transplantation according to Milan-NET criteria were offered transplant (n = 42) versus nontransplant options (n = 46) depending on list dynamics, patient disposition, and age. Tumor burden between groups did not differ. Transplant patients were younger (40.5 vs. 55.5 years; p < 0.001). Long-term outcomes were compared after matching between groups made on multiple Cox models adjusted for propensity score built on logistic models. Survival benefit was the difference in mean survival between transplant versus nontransplant options. No patients were lost or died without recurrence. Median follow-up was 122 months. The transplant group showed a significant advantage over nontransplant strategies at 5 and 10 years in survival (97.2% and 88.8% vs. 50.9% and 22.4%, respectively; p < 0.001) and time-to-progression (13.1% and 13.1% vs. 83.5% and 89%; p < 0.001). After adjustment for propensity score, survival advantage of the transplant group was significant (hazard ratio = 7.4; 95% confidence interval (CI): 2.4-23.0; p = 0.001). Adjusted transplant-related survival benefit was 6.82 months (95% CI: 1.10-12.54; p = 0.019) and 38.43 months (95% CI: 21.41-55.45; p < 0.001) at 5 and 10 years, respectively. Liver transplantation for metastatic NETs under restrictive criteria provides excellent long-term outcome. Transplant-related survival benefit increases over time and maximizes after 10 years.

Inverse expression of somatostatin and CXCR4 chemokine receptors in gastroenteropancreatic neuroendocrine neoplasms of different malignancy

INTRODUCTION

Somatostatin receptors (SSTR) are widely distributed in well-differentiated neuroendocrine neoplasms (NEN) and serve as primary targets for diagnostics and treatment. An overexpression of the chemokine receptor CXCR4, in contrast, is considered to be present mainly in highly proliferative and advanced tumors. Comparative data are still lacking, however, for neuroendocrine carcinomas (NEC).

METHODS

SSTR subtype (1, 2A, 3, 5) and CXCR4 expression was evaluated in G1 (n = 31), G2 (n = 47), and low (G3a; Ki-67: 21-49%; n = 21) and highly proliferative (G3b; Ki-67: >50%, n = 22) G3 (total n = 43) gastroenteropancreatic NEN samples by performing immunohistochemistry with monoclonal rabbit anti-human anti-SSTR and anti-CXCR4 antibodies, respectively, and was correlated with clinical data.

RESULTS

Both CXCR4 and SSTR were widely expressed in all tumors investigated. CXCR4 expression differed significantly between the G1 and G3 specimens and within the G3 group (G3a to G3b), and was positively correlated with Ki-67 expression. SSTR2A, in contrast, exhibited an inverse association with Ki-67. SSTR2A was highly expressed in G1 and G2 tumors, but was significantly less abundant in G3 carcinomas. Additionally, SSTR1 expression was higher in G3a than in G3b tumors.

CONCLUSION

We observed an elevation in CXCR4 and a decrease in SSTR2A expression with increasing malignancy. Interestingly, 23% of the G3 specimens had strong SSTR2A expression. Because CXCR4 was strongly expressed in highly proliferative G3 carcinomas, it is an interesting new target and needs to be validated in larger studies.

Antiangiogenic and antihepatocellular carcinoma activities of the Juniperus chinensis extract

Background

To identify a novel therapeutic agent for hepatocellular carcinoma (HCC), for which no promising therapeutic agent exists, we screened a panel of plants and found that Juniperus chinensis exhibited potential antiangiogenic and anti-HCC activities. We further investigated the antiangiogenic and anti-HCC effects of the active ingredient of J. chinensis extract, CBT-143-S-F6F7, both in vitro and in vivo.

Methods

A tube formation assay conducted using human umbilical vein endothelial cells (HUVECs) was first performed to identify the active ingredient of CBT-143-S-F6F7. A series of angiogenesis studies, including HUVEC migration, Matrigel plug, and chorioallantoic membrane (CAM) assays, were then performed to confirm the effects of CBT-143-S-F6F7 on angiogenesis. The effects of CBT-143-S-F6F7 on tumor growth were investigated using a subcutaneous and orthotopic mouse model of HCC. In vitro studies were performed to investigate the effects of CBT-143-S-F6F7 on the cell cycle and apoptosis in HCC cells. Moreover, protein arrays for angiogenesis and apoptosis were used to discover biomarkers that may be influenced by CBT-143-S-F6F7. Finally, nuclear magnetic resonance analysis was conducted to identify the compounds of CBT-143-S-F6F7.

Results

CBT-143-S-F6F7 showed significantly antiangiogenic activity in various assays, including HUVEC tube formation and migration, CAM, and Matrigel plug assays. In in vivo studies, gavage with CBT-143-S-F6F7 significantly repressed subcutaneous Huh7 tumor growth in severe combined immunodeficient (SCID) mice, and prolonged the survival of orthotopic Huh7 tumor-bearing SCID mice (a 40 % increase in median survival duration compared with the vehicle-treated mice). Immunohistochemical staining of subcutaneous Huh7 tumors in CBT-143-S-F6F7-treated mice showed a significantly decrease in the cell cycle regulatory protein cyclin D1, cellular proliferation marker Ki-67, and endothelial marker CD31. CBT-143-S-F6F7 caused arrest of the G2/M phase and induced Huh7 cell apoptosis, possibly contributing to the inhibition of HCC tumors. Protein array analysis revealed that several angiogenic and antiapoptotic factors were suppressed in CBT-143-S-F6F7-treated Huh7 cells. Finally, five compounds from CBT-143-S-F6F7 were identified.

Conclusions

According to these results, we report for the first time the antiangiogenic and anti-HCC activities of CBT-143-S-F6F7, the active fractional extract of J. chinensis. We believe that CBT-143-S-F6F7 warrants further evaluation as a new anti-HCC drug.

Electronic supplementary material

The online version of this article (doi:10.1186/s12906-016-1250-6) contains supplementary material, which is available to authorized users.

Subgroup analysis of patients with G2 gastroenteropancreatic neuroendocrine tumors

Neuroendocrine tumors (NET) are malignancies with an increasing incidence rate. NETs are graded or classified by the expression level of Ki67, a proliferation marker in Grade 1 and 2 tumors. Out of 120 patients who visited our hospital between 2003 and 2012, 40 were classified as G2 NET. This study was mainly designed to investigate a new threshold for optimising the Ki67 system. Patients were subdivided into two new groups according to Ki67 (group 1 = 3-9%, group 2 = 10-20%). Twenty-five patients were allocated to group 1 and 15 to group 2. The primary tumor originated in 46% from the foregut and 68% NET were functionally active. Patients were treated in 88 versus 60% by surgery, 48 versus 80% by somatostatin analogs, 0 versus 20% by chemotherapy, 2,5 versus 0% by Everolimus and 32 versus 47% underwent peptide receptor radionuclide therapy. Group 1 patients showed a significantly (p = 0.01) better survival compared with group 2 and also a significant difference of Chromogranin A (p = 0.03) and alkaline phosphatase (p = 0.01). In addition, all patients with elevated lactate dehydrogenase showed a significantly (p = 0.03) shorter survival. Prognostic relevance of G2 NETs may be improved by using a new boundary. Patients with Ki67 of 3-9% showed a better response to current treatment methods and significantly longer survival compared to group 2. Thus, our data clearly show that patients with higher G2 proliferation index should be treated differently. Finally, LDH has been found to be a new prognostic factor in patients with G2 NET.

Ki67 as a prognostic factor for long-term outcome following surgery in gastrointestinal stromal tumors

OBJECTIVE

This study aimed to examine the value of Ki67 expression along with other potential prognostic factors for predicting overall survival and disease-free survival in patients with gastrointestinal stromal tumors who underwent curative resection.

PATIENTS AND METHODS

Sixty-eight histologically confirmed and operated patients with gastrointestinal stromal tumors were included. Clinical and follow-up data were retrieved from medical records and patients were contacted at the end of the study. The effects of certain clinical and histopathological parameters on survival outcomes were examined.

RESULTS

Sixty-eight patients were followed for a mean duration of follow-up of 2923.3 patient-months. Twelve deaths (17.6%), seven metastasis (10.3%), and two local recurrences (2.9%) occurred. Overall survival was 102.5 months [95% confidence interval (CI), 88.3-116.8] and disease-free survival was 91.8 months (95% CI, 76.5-107.2). Multivariate analyses identified a high Ki67 index (≥ 10%) as an independent predictor of both poor overall survival (hazard ratio, 4.8; 95% CI 1.2-19.2; P=0.027) and poor disease-free survival (hazard ratio, 15.3; 95% CI, 4.7-50.2).

CONCLUSION

A high Ki67 expression seems to be a useful prognostic factor that would aid in predicting disease course in gastrointestinal stromal tumors. These findings deserve further investigation in larger studies.

Expression of CD24, a Stem Cell Marker, in Pancreatic and Small Intestinal Neuroendocrine Tumors

OBJECTIVES

CD24 has been considered a normal and cancer stem cell marker. Potential intestinal stem cells weakly express CD24. In the pancreas, CD24 is a possible cancer stem cell marker for ductal adenocarcinoma.

METHODS

Expression of CD24 in intestinal and pancreatic neuroendocrine tumors (NETs) was examined. Immunohistochemistry was performed on benign duodenum, ileum mucosa, and pancreas, as well as primary duodenal, primary and metastatic ileal, and pancreatic NETs.

RESULTS

Scattered CD24-positive cells were noted in the duodenal and ileal crypts, most of which showed a strong subnuclear labeling pattern. Similar expression was observed in 41 (95%) of 43 primary ileal NETs but in only four (15%) of 26 duodenal NETs (P < .01). In addition, metastatic ileal NETs retained CD24 expression. Pancreatic islets did not express CD24, and only rare cells had subnuclear labeling of CD24 in the pancreatic ducts. Unlike ileal NETs, only five (5%) of 92 pancreatic NETs expressed CD24 in the subnuclear compartment (P < .01). All five NETs showed a unique morphology with prominent stromal fibrosis.

CONCLUSIONS

CD24 expression was frequent in primary and metastatic midgut NETs but rare in pancreatic and duodenal NETs. Expression of CD24 in ileal NETs may have future diagnostic and therapeutic implications.

Unusual endoscopic findings of gastric neuroendocrine tumor

Gastric neuroendocrine tumor (NET) is sometimes found as a submucosal tumor on upper gastrointestinal endoscopy. Gastric NET with malignant profile and neuroendocrine carcinoma (NEC) show various forms which are difficult to distinguish from gastric cancer and other disease. We report a case of a cauliflower-shaped NET of the stomach. A 61-year-old man was referred to our hospital with a complaint of abdominal fullness. Upper gastrointestinal endoscopic examination revealed an unusual, whitish cauliflower-shaped tumor that belongs to Borrmann type I on the lesser curvature of the gastric antrum. Histological examination of the biopsy specimen revealed NET G2, because the tumor cells were CD56- and synaptophysin-positive by immunohistochemical analysis. A distal gastrectomy with D2 lymphadenectomy was performed. A recurrence in the liver was revealed by follow up computed tomography after 11 months from operation. Combined chemotherapy with irinotecan (CPT-11) plus cisplatin (CDDP) was treated. The patient achieved a partial response, but he died after 31 months from gastrectomy. There is no independent, large-scaled prospective study and no standard treatment for gastric NETs with distant metastases. Our case is reported with a literature review of the treatment of metastatic gastric NET G2.

Discordance of Histologic Grade Between Primary and Metastatic Neuroendocrine Carcinomas

BACKGROUND

The prognosis and management of neuroendocrine carcinoma are largely driven by histologic grade as assessed by mitotic activity. The authors reviewed their institutional experience to determine whether the histologic grade of neuroendocrine carcinoma can differ between primary and metastatic tumors.

METHODS

This study examined patients who underwent operative resection of both primary and metastatic foci of neuroendocrine carcinoma. Resected tumors were independently reviewed and categorized as low, intermediate, or high grade as determined by mitotic count.

RESULTS

The authors identified 20 patients with metastatic neuroendocrine carcinoma treated at their institution between 1997 and 2013 for whom complete pathologic review of primary and metastatic tumors was possible. Primary lesions were found in the small intestine (n = 12), pancreas (n = 7), ampulla (n = 1), stomach (n = 1), and rectum (n = 1). The timing of hepatic metastasis was synchronous in 15 cases and metachronous in 5 cases. The histologic grade was concordant between primary and metastatic tumors in 9 cases and discordant in 11 cases. Among the discordant cases, 7 had a higher metastatic grade than primary grade, and 4 had a lower metastatic grade than primary grade. Metachronous presentation was associated with a higher likelihood of grade discordance (p = 0.03). The histologic grade of all metachronous metastases differed from that of the primary tumors.

CONCLUSION

There is a high prevalence of histologic grade discordance between primary and metastatic foci of neuroendocrine carcinoma, particularly among patients with a metachronous metastatic presentation. Given the importance of histologic grade in disease prognostication and treatment planning, this finding may be informative for the management of patients with metastatic neuroendocrine carcinoma.

Transcatheter embolization therapy in liver cancer: an update of clinical evidences

Transarterial chemoembolization (TACE) is a form of intra-arterial catheter-based chemotherapy that selectively delivers high doses of cytotoxic drug to the tumor bed combining with the effect of ischemic necrosis induced by arterial embolization. Chemoembolization and radioembolization are at the core of the treatment of liver hepatocellular carcinoma (HCC) patients who cannot receive potentially curative therapies such as transplantation, resection or percutaneous ablation. TACE for liver cancer has been proven to be useful in local tumor control, to prevent tumor progression, prolong patients' life and control patient symptoms. Recent evidence showed in patients with single-nodule HCC of 3 cm or smaller without vascular invasion, the 5-year overall survival (OS) with TACE was similar to that with hepatic resection and radiofrequency ablation. Although being used for decades, Lipiodol(®) (Lipiodol(®) Ultra Fluid(®), Guerbet, France) remains important as a tumor-seeking and radio-opaque drug delivery vector in interventional oncology. There have been efforts to improve the delivery of chemotherapeutic agents to tumors. Drug-eluting bead (DEB) is a relatively novel drug delivery embolization system which allows for fixed dosing and the ability to release the anticancer agents in a sustained manner. Three DEBs are available, i.e., Tandem(®) (CeloNova Biosciences Inc., USA), DC-Beads(®) (BTG, UK) and HepaSphere(®) (BioSphere Medical, Inc., USA). Transarterial radioembolization (TARE) technique has been developed, and proven to be efficient and safe in advanced liver cancers and those with vascular complications. Two types of radioembolization microspheres are available i.e., SIR-Spheres(®) (Sirtex Medical Limited, Australia) and TheraSphere(®) (BTG, UK). This review describes the basic procedure of TACE, properties and efficacy of some chemoembolization systems and radioembolization agents which are commercially available and/or currently under clinical evaluation. The key clinical trials of transcatheter arterial therapy for liver cancer are summarized.

Liver transplantation for malignancies

Liver transplantation (LT) has become an acceptable and effective treatment for selected patients with hepatocellular carcinoma with excellent outcomes. More recently, LT has been tried in different primary and secondary malignancies of the liver. The outcomes of LT for very selected group of patients with hilar cholangiocarcinoma (CCA) have been promising. Excellent results have been reported in LT for patients with unresectable hepatic epithelioid hemangioendothelioma (HEHE). In contrast to excellent results after LT for HEHE, results of LT for angiosarcoma have been disappointing with no long-term survivors. Hepatoblastoma (HB) is the most common primary liver cancer in pediatric age group. Long-term outcomes after LT in patients with unresectable tumor and good response to chemotherapy have been promising. Indication for LT for hepatic metastasis from neuroendocrine tumors (NETs) is mainly for patients with unresectable tumors and for palliation of medically uncontrollable symptoms. Posttransplant survival in those patients with low tumor activity index is excellent, despite recurrence of the tumor. More recent limited outcomes data on LT for unresectable hepatic metastases from colorectal cancer have claimed some survival benefit compared to the previous reports. However, due to the high rate of tumor recurrence in a very short time after LT, especially in the era of organ shortage, this indication has not been favored by the transplant community.

Perspectives on surgical management of neuroendocrine liver metastases

Abstract: 

Neuroendocrine tumors (NETs) commonly metastasize to the liver. Different treatments are available for the management of metastatic NETs. Both primary tumor and metastases can significantly affect the patients’ quality of life and overall survival (OS). Surgical resection is the only chance for cure and should be considered for every patient. For operable patients, current evidence suggests that liver resection is a safe and effective treatment for neuroendocrine liver metastases. High rates of recurrence are reported following resection of neuroendocrine liver metastases. There is no evidence to support incomplete (R2) resection (debulking) surgery to improve OS or quality of life. When surgery is performed for NETs, other conservative adjuvant treatments should also be considered to prolong symptom-free, disease-free and OS.