Current considerations on intraductal papillary neoplasms of the bile duct and pancreatic duct

Pancreatobiliary intraductal papillary neoplasms(IPNs)represent precursors of pancreatic cancer or bile duct cholangiocarcinoma that can be detected and treated.Despite advances in diagnostic methods,identifying these premalignant lesions is still challenging for treatment providers.Modern imaging,biomarkers and molecular tests for genomic alterations can be used for diagnosis and follow-up.Surgical intervention in combination with new chemotherapeutic agents is considered the optimal treatment for malignant cases.The balance between the risk of malignancy and any risk of resection guides management policy;therefore,treatment should be individualized based on a meticulous preoperative assessment of high-risk stigmata.IPN of the bile duct is more aggressive;thus,early diagnosis and surgery are crucial.The conservative management of low-risk pancreatic branch-duct lesions is safe and effective.

Comparison between solid pseudopapillary neoplasms of the pancreas and pancreatic ductal adenocarcinoma with cystic changes using computed tomography

BACKGROUND Solid pseudopapillary neoplasms of the pancreas(SPN)share similar imaging findings with pancreatic ductal adenocarcinoma with cystic changes(PDAC with cystic changes),which may result in unnecessary surgery.AIM To investigate the value of computed tomography(CT)in differentiation of SPN from PDAC with cystic changes.METHODS This study retrospectively analyzed the clinical and imaging findings of 32 patients diagnosed with SPN and 14 patients diagnosed with PDAC exhibiting cystic changes,confirmed through pathological diagnosis.Quantitative and qualitative analysis was performed,including assessment of age,sex,tumor size,shape,margin,density,enhancement pattern,CT values of tumors,CT contrast enhancement ratios,“floating cloud sign,”calcification,main pancreatic duct dilatation,pancreatic atrophy,and peripancreatic invasion or distal metastasis.Multivariate logistic regression analysis was used to identify relevant features to differentiate between SPN and PDAC with cystic changes,and receiver operating characteristic curves were obtained to evaluate the diagnostic performance of each variable and their combination.RESULTS When compared to PDAC with cystic changes,SPN had a lower age(32 years vs 64 years,P<0.05)and a slightly larger size(5.41 cm vs 3.90 cm,P<0.05).SPN had a higher frequency of“floating cloud sign”and peripancreatic invasion or distal metastasis than PDAC with cystic changes(both P<0.05).No significant difference was found with respect to sex,tumor location,shape,margin,density,main pancreatic duct dilatation,calcification,pancreatic atrophy,enhancement pattern,CT values of tumors,or CT contrast enhancement ratios between the two groups(all P>0.05).The area under the receiver operating characteristic curve of the combination was 0.833(95%confidence interval:0.708-0.957)with 78.6%sensitivity,81.3%specificity,and 80.4%accuracy in differentiation of SPN from PDAC with cystic changes.CONCLUSION A larger tumor size,“floating cloud sign,”and peripancreatic invasion or distal metastasis are useful CT imaging features that are more common in SPN and may help discriminate SPN from PDAC with cystic changes.

Identification of breath volatile organic compounds to distinguish pancreatic adenocarcinoma,pancreatic cystic neoplasm,and patients without pancreatic lesions

BACKGROUND Volatile organic compounds(VOCs)are a promising potential biomarker that may be able to identify the presence of cancers.AIM To identify exhaled breath VOCs that distinguish pancreatic ductal adenocar-cinoma(PDAC)from intraductal papillary mucinous neoplasm(IPMN)and healthy volunteers.METHODS We collected exhaled breath from histologically proven PDAC patients,radiological diagnosis IPMN,and healthy volunteers using the ReCIVA®device between 10/2021-11/2022.VOCs were identified by thermal desorption-gas chromatography/field-asymmetric ion mobility spectrometry and compared between groups.RESULTS A total of 156 participants(44%male,mean age 62.6±10.6)were enrolled(54 PDAC,42 IPMN,and 60 controls).Among the nine VOCs identified,two VOCs that showed differences between groups were dimethyl sulfide[0.73 vs 0.74 vs 0.94 arbitrary units(AU),respectively;P=0.008]and acetone dimers(3.95 vs 4.49 vs 5.19 AU,respectively;P<0.001).After adjusting for the imbalance parameters,PDAC showed higher dimethyl sulfide levels than the control and IPMN groups,with adjusted odds ratio(aOR)of 6.98(95%CI:1.15-42.17)and 4.56(1.03-20.20),respectively(P<0.05 both).Acetone dimer levels were also higher in PDAC compared to controls and IPMN(aOR:5.12(1.80-14.57)and aOR:3.35(1.47-7.63),respectively(P<0.05 both).Acetone dimer,but not dimethyl sulfide,performed better than CA19-9 in PDAC diagnosis(AUROC 0.910 vs 0.796).The AUROC of acetone dimer increased to 0.936 when combined with CA19-9,which was better than CA19-9 alone(P<0.05).CONCLUSION Dimethyl sulfide and acetone dimer are VOCs that potentially distinguish PDAC from IPMN and healthy participants.Additional prospective studies are required to validate these findings.

Malignancy risk factors and prognostic variables of pancreatic mucinous cystic neoplasms in Chinese patients

BACKGROUND Pancreatic mucinous cystic neoplasms(MCNs)represent one of the precursor lesions of pancreatic ductal adenocarcinoma,and their detection has been facilitated by advances in preoperative imaging.Due primarily to the rarity of MCNs,however,there is limited knowledge regarding the prognostic variables and high-risk factors for malignant transformation.A more comprehensive and nuanced approach is necessary to fill this gap and provide a basis for improved treatment decisions and patient outcomes.AIM To investigate the high-risk factors associated with malignant MCNs and to explore the prognostic factors of MCN with associated invasive carcinoma(MCNAIC).METHODS All cases of resected MCNs from a single high-volume institution between January 2012 and January 2022 were retrospectively reviewed.Only cases with ovarian-type stroma verified by progesterone receptor staining were included.Preoperative features,histological findings and postoperative course were documented.Multivariate logistic regression was employed to investigate variables related to malignancy.Survival analysis was performed using the Kaplan-Meier curve,and the prognostic factors were assessed to evaluate the postoperative course of patients with MCN-AIC.RESULTS Among the 48 patients,36 had benign MCNs,and 12 had malignant MCNs(1 high-grade atypical hyperplasia and 11 MCN-AIC).Age,tumour size,presence of solid components or mural nodules and pancreatic duct dilatation were identified as independent risk factors associated with malignancy.The follow-up period ranged from 12 mo to 120 mo,with a median overall survival of 58.2 mo.Only three patients with MCN-AIC died,and the 5-year survival rate was 70.1%.All 11 cases of MCN-AIC were stage I,and extracapsular invasion was identified as a prognostic factor for poorer outcomes.CONCLUSION The risk factors independently associated with malignant transformation of MCNs included age,tumour size,presence of solid components or mural nodules,and pancreatic duct dilatation.Our study also revealed that encapsulated invasion was a favourable prognostic factor in MCN-AIC patients.

Surgical management of pancreatic neuroendocrine neoplasms

Pancreatic neuroendocrine neoplasms are a rare and complex group of neoplastic lesions that develop from pancreatic islet cells.Their incidence has dramatically increased during the last two decades.Due to its complex nature and pathophysiological behaviour,surgical management continues to evolve.Surgery remains the cornerstone of treatment for most non-functional and functional pancreatic neuroendocrine tumours,while lymphadenectomy remains a controversial subject.Different techniques,such as pancreas-preserving and minimally invasive approaches,continue to evolve and offer the same overall outcomes as open surgery.This comprehensive review describes in detail the current and most up-todate classification and staging of pancreatic neuroendocrine tumours,explores the rationale for nonsurgical and surgical management,and focuses on surgical treatment and more specifically,on minimally invasive approaches.

Pancreatic cystic neoplasms:a comprehensive approach to diagnosis and management

Pancreatic cystic neoplasms present a complex diagnostic scenario encompassing low-and high-grade malignancies.Their prevalence varies widely,notably increasing with age,reaching 75%in individuals older than 80 years.Accurate diagnosis is crucial,as errors occur in approximately one-third of resected cysts discovered incidentally.Various imaging modalities such as computed tomography,magnetic resonance imaging,and endoscopic techniques are available to address this challenge.However,risk stratification remains problematic,with guideline inconsistencies and diagnostic accuracy varying according to cyst type.This review proposed a stepwisemanagement approach,considering patient factors,imaging results,and specific features.This patient-centered model offers a structured framework for optimizing the care of individuals with pancreatic cystic neoplasms.

High-grade pancreatic intraepithelial neoplasia diagnosed based on changes in magnetic resonance cholangiopancreatography findings:A case report

BACKGROUND High-grade pancreatic intraepithelial neoplasia(PanIN)exhibits no mass and is not detected by any examination modalities.However,it can be diagnosed by pancreatic juice cytology from indirect findings.Most previous cases were diagnosed based on findings of a focal stricture of the main pancreatic duct(MPD)and caudal MPD dilatation and subsequent pancreatic juice cytology using endoscopic retrograde cholangiopancreatography(ERCP).We experienced a case of high-grade PanIN with an unclear MPD over a 20-mm range,but without caudal MPD dilatation on magnetic resonance cholangiopancreatography(MRCP).CASE SUMMARY A 60-year-old female patient underwent computed tomography for a follow-up of uterine cancer post-excision,which revealed pancreatic cysts.MRCP revealed an unclear MPD of the pancreatic body at a 20-mm length without caudal MPD dilatation.Thus,course observation was performed.After 24 mo,MRCP revealed an increased caudal MPD caliber and a larger pancreatic cyst.We performed ERCP and detected atypical cells suspected of adenocarcinoma by serial pancreatic juice aspiration cytology examination.We performed a distal pancreatectomy and obtained a histopathological diagnosis of high-grade PanIN.Pancreatic parenchyma invasion was not observed,and curative resection was achieved.CONCLUSION High-grade Pan-IN may cause MPD narrowing in a long range without caudal MPD dilatation.

Pancreatic neuroendocrine tumors:Are tumors smaller than 2 cm truly indolent?

BACKGROUND Pancreatic neuroendocrine tumors(PNETs)are relatively rare but rank as the second most common pancreatic neoplasm.They can be functional,causing early metabolic disturbances due to hormone secretion,or non-functional and diagnosed later based on tumor size-related symptoms.Recent diagnoses of PNETs under 2 cm in size have sparked debates about their management;some practitioners advocate for surgical removal and others suggest observation due to the tumors’lower potential for malignancy.However,it is unclear whether managing these small tumors expectantly is truly safe.AIM To evaluate poor prognostic factors in PNETs based on tumor size(>2 cm or<2 cm)in surgically treated patients.METHODS This cohort study included 64 patients with PNETs who underwent surgical resection between 2006 and 2019 at a high-complexity reference hospital in Medellín,Colombia.To assess patient survival,quarterly follow-ups were conducted during the first year after surgery,followed by semi-annual con-sultations at the hospital's hepatobiliary surgery department.Qualitative variables were described using absolute and relative frequencies,and quantitative variables were expressed using measures of central tendency and their corresponding measures of dispersion.RESULTS The presence of lymph node involvement,neural involvement,and lymphovascular invasion were all associated with an increased risk of mortality,with hazard ratios of 5.68(95%CI:1.26–25.61,P=0.024),6.44(95%CI:1.43–28.93,P=0.015),and 24.87(95%CI:2.98–207.19,P=0.003),respectively.Neural involvement and lymphovascular invasion were present in tumors smaller than 2 cm in diameter and those larger than 2 cm in diameter.The recurrence rates between the two tumor groups were furthermore similar:18.2%for tumors smaller than 2 cm and 21.4%for tumors larger than 2 cm.Patient survival was additionally comparable between the two tumor groups.CONCLUSION Tumor size does not dictate prognosis;lymph node and lymphovascular involvement affect mortality,which high-lights that histopathological factors-rather than tumor size-may play a role in management.

Solid pseudopapillary tumor of the pancreas:A systematic review of clinical,surgical and oncological characteristics of 1384 patients underwent pancreatic surgery

Background:Pancreatic solid pseudopapillary tumors(SPTs)are rare clinical entity,with low malignancy and still unclear pathogenesis.They account for less than 2%of exocrine pancreatic neoplasms.This study aimed to perform a systematic review of the main clinical,surgical and oncological characteristics of pancreatic SPTs.Data sources:MEDLINE/PubMed,Web of Science and Scopus databases were systematically searched for the main clinical,surgical and oncological characteristics of pancreatic SPTs up to April 2021,in accordance with the preferred reporting items for systematic reviews and meta-analyses(PRISMA)standards.Primary endpoints were to analyze treatments and oncological outcomes.Results:A total of 823 studies were recorded,86 studies underwent full-text reviews and 28 met inclusion criteria.Overall,1384 patients underwent pancreatic surgery.Mean age was 30 years and 1181 patients(85.3%)were female.The most common clinical presentation was non-specific abdominal pain(52.6%of cases).Mean overall survival was 98.1%.Mean recurrence rate was 2.8%.Mean follow-up was 4.2 years.Conclusions:Pancreatic SPTs are rare,and predominantly affect young women with unclear pathogenesis.Radical resection is the gold standard of treatment achieving good oncological impact and a favorable prognosis in a yearly life-long follow-up.

Early diagnosis of pancreatic cancer: Shedding light on an unresolved challenge

Diagnosing early-stage pancreatic cancer(PC)remains a clinical challenge.Hence,studying novel imaging aspects that could enhance the diagnostic accuracy of malignant pancreatic precursor lesions is imperative.This article aims to un-derscore the promising role of emerging imaging aspects that may facilitate the earlier diagnosis of PC,thereby improving its management and prognosis.

Early detection of pancreatic cancer

The diagnosis of pancreatic cancer associates an appalling significance.Detection of preinvasive stage of pancreatic cancer will ameliorate the survival of this deadly disease.Premalignant lesions such as Intraductal Papillary Mucinous Neoplasms or Mucinous Cystic Neoplasms of the pancreas are detectable on imaging exams and this permits their management prior their invasive development.Pancreatic intraepithelial neoplasms(PanIN)are the most frequent precursors of pancreatic adenocarcinoma(PDAC),and its particular type PanIN high-grade represents the malignant non-invasive form of PDAC.Unfortunately,PanINs are not detectable on radiologic exams.Nevertheless,they can associate indirect imaging signs which would rise the diagnostic suspicion.When this suspicion is established,the patient will be enrolled in a follow-up strategy that includes performing of blood test and serial imaging test such as computed tomography or magnetic resonance imaging,which will cost in the best-case scenario a burden of healthcare systems,and potential mortality in the worst-case scenario when the patient underwent resection surgery,worthless when there is no moderate or high grade dysplasia in the final histopathology.This issue will be avoid having at its disposal a diagnostic technique capable of detecting high-grade PanIN lesions,such is the cytology of pancreatic juice obtained by nasopancreatic intubation.Herein,we review the possibility of detection of early malignant lesions before they become invasive PADC.

Mixed pancreatic ductal adenocarcinoma and well-differentiated neuroendocrine tumor:A case report

BACKGROUND Pancreatic mixed neuroendocrine-non-neuroendocrine neoplasms(MiNENs)are rare malignancies affecting the pancreas.The World Health Organization defines MiNENs as neoplasms composed of morphologically recognizable neuroendocrine and non-neuroendocrine components,each constituting 30%or more of the tumor volume.Adenocarcinoma-neuroendocrine carcinoma is the most frequent MiNEN combination.A well-differentiated neuroendocrine tumor(NET)component is rarely reported in MiNENs.CASE SUMMARY Here we report a rare case with intermingled components of ductal adenocarcinoma and grade 1 well-differentiated NET in the pancreas.The two tumors show distinct histology and significant differentiation discrepancy(poorly differentiated high grade adenocarcinoma and well-differentiated low grade NET),and also present as metastases in separate lymph nodes.Next generation sequencing of the two components demonstrates KRAS and TP53 mutations in the ductal adenocarcinoma,but no genetic alterations in the NET,suggesting divergent origins for these two components.Although tumors like this meet the diagnostic criteria for MiNEN,clinicians often find the diagnosis and staging confusing and impractical for clinical management.CONCLUSION Mixed NET/non-NET tumors with distinct histology and molecular profiles might be better classified as collision tumors rather than MiNENs.

Percutaneous transhepatic intraportal biopsy using gastroscope biopsy forceps for diagnosis of a pancreatic neuroendocrine neoplasm:A case report

BACKGROUND Pancreatic neuroendocrine neoplasms(PNENs)are a rare group of neoplasms originating from the islets of the Langerhans.Portal vein tumor thrombosis has been reported in 33%of patients with PNENs.While the histopathological diagnosis of PNENs is usually based on percutaneous biopsy or endoscopic ultrasound-guided fine-needle aspiration(EUS-FNA),these approaches may be impeded by gastric varices,poor access windows,or anatomically contiguous critical structures.Obtaining a pathological diagnosis using a gastroscope biopsy forceps via percutaneous transhepatic intravascular pathway is an innovative method that has rarely been reported.CASE SUMMARY A 72-year-old man was referred to our hospital for abdominal pain and melena.Abdominal contrast-enhanced magnetic resonance imaging revealed a wellenhanced tumor(size:2.4 cm×1.2 cm×1.2 cm)in the pancreatic tail with portal vein invasion.Traditional pathological diagnosis via EUS-FNA was not possible because of diffuse gastric varices.We performed a percutaneous transportal biopsy of the portal vein tumor thrombus using a gastroscope biopsy forceps.Histopathologic examination revealed a pancreatic neuroendocrine neoplasm(G2)with somatostatin receptors 2(+),allowing systemic treatment.CONCLUSION Intravascular biopsy using gastroscope biopsy forceps appears to be a safe and effective method for obtaining a histopathological diagnosis.Although welldesigned clinic trials are required to obtain more definitive evidence,this procedure may help improve the diagnosis of portal vein thrombosis and related diseases.

Rapid transformation of branched pancreatic duct-derived intraductal tubulopapillary neoplasm into an invasive carcinoma: A case report

BACKGROUND Intraductal tubulopapillary neoplasm(ITPN)is a rare disease accounting for approximately 3%of all intraductal pancreatic tumors,with intraductal papillary mucinous neoplasm(IPMN)being one of the most common differential diagnoses.Both ITPN and IPMN display slow growth.A branched pancreatic duct type is commonly observed in IPMN,whereas ITPN derived from the branched pancreatic duct has been reported in a limited number of cases;hence,its pathogenesis remains unclear.CASE SUMMARY Here,we present the case of a patient with ITPN localized in a branched pancreatic duct,with poorly controlled irritable bowel syndrome.A contrastenhanced computed tomography scan of the abdomen incidentally revealed a 5-mm oligemic nodule-like change in the body of the pancreas.Endoscopic ultrasound(EUS)indicated a 10-mm hypoechoic mass without any cystic structures that had grown within 2 mo.EUS-guided fine needle aspiration was performed for definitive diagnosis,and the findings suggested ductal papillary carcinoma.Distal pancreatectomy was performed,and the tumor was pathologically diagnosed as ITPN with an invasive cancerous component,pT3N1aM0,pStage IIB(International Cancer Control,8^(th) edition).The patient underwent treatment with postoperative adjuvant chemotherapy(S-1 monotherapy);however,relapse was observed 1 year and 10 mo after surgical resection,and subsequent treatment involving a combination of chemotherapy and radiotherapy was administered.Maintenance therapy has since facilitated a stable disease state.CONCLUSION Regardless of the microscopic size of the neoplasm,early diagnosis of ITPN with EUS-guided fine needle aspiration and surgical resection are crucial.

Current perspectives on pancreatic serous cystic neoplasms:Diagnosis, management and beyond

Pancreatic cystic neoplasms have been increasingly recognized recently. Comprising about 16% of all resected pancreatic cystic neoplasms, serous cystic neoplasms are uncommon benign lesions that are usually asymptomatic and found incidentally. Despite overall low risk of malignancy, these pancreatic cysts still generate anxiety, leading to intensive medical investigations with considerable financial cost to health care systems. This review discusses the general background of serous cystic neoplasms, including epidemiology and clinical characteristics, and provides an updated overview of diagnostic approaches based on clinical features, relevant imaging studies and new findings that are being discovered pertaining to diagnostic evaluation. We also concisely discuss and propose management strategies for better quality of life.

Difficulty with diagnosis of malignant pancreatic neoplasms coexisting with chronic pancreatitis

Chronic pancreatitis is a relatively common disease. We encountered two different cases of belatedly demonstrated pancreatic carcinoma featuring underlying chronic pancreatitis. The first case was one that was highly suspected as that of a malignancy based upon imaging study, but unfortunately, it could not be confirmed by intra-operative cytology at that time. Following this, the surgeon elected to perform only conservative bypass surgery for obstructive biliary complication. Peritoneal carcinomatosis was later noted and the patient finally died. The second case, a malignant mucinous neoplasm,was falsely diagnosed as a pseudocyst, based upon the lesion's sonographic appearance and associated elevated serum amylase levels. After suffering repeated hemoptysis,the patient was found to exhibit lung metastasis and peritoneal seeding. We reviewed some of the literature,including those studies discussing chronic pancreatitis predisposing to a malignant change. These two case analyses illustrate clearly that the diagnosis for such conditions, which is simply based upon imagery or pathological considerations may end up being one of a mistaken malignancy. Some of our suggestions for the treatment of such malignancies as revealed herein include,total pancreatomy for univocal mass lesion, and needle aspiration of lesion-contained tissue for amylase, CA199and CEA levels for a suspicious cystic pancreatic mass.

Intraductal papillary mucinous neoplasms and other pancreatic cystic lesions

Pancreatic cystic neoplasms are being increasingly recognized, even in the absence of symptoms, in large part, due to markedly improved imaging modalities such as magnetic resonance imaging (MRI)/magnetic resonance cholangio pancreatography (MRCP) and computer tomography (CT) scanning. During the past 2 decades, better imaging of these cystic lesions has resulted in definition of different types, including pancreatic intraductal papillary mucinous neoplasms (IPMN). While IPMN represent only a distinct minority of all pancreatic cancers, they appear to be a relatively frequent neoplastic form of pancreatic cystic neoplasm. Moreover, IPMN have a much better outcome and prognosis compared to pancreatic ductal adenocarcinomas. Therefore, recognition of this entity is exceedingly important for the clinician involved in diagnosis and further evaluation of a potentially curable form of pancreatic cancer.

Pancreatic intraductal papillary mucinous neoplasms:Current diagnosis and management

Intraductal papillary mucinous neoplasms(IPMNs)represent approximately 1%of all pancreatic neoplasms and 25%of cystic neoplasms.They are divided into three types:main duct-IPMN(MD-IPPMN),branch duct-IPMN(BD-IPMN),and mixed type-IPMN.In this review,diagnostics,including clinical presentation and radiological investigations,were described.Magnetic resonance imaging is the most useful for most IPMNs.Management depends on the type and radiological features of IPMNs.Surgery is recommended for MD-IPMN.For BD-IPMN,management involves surgery or surveillance depending on the tumor size,cyst growth rate,solid components,main duct dilatation,high-grade dysplasia in cytology,the presence of symptoms(jaundice,new-onset diabetes,pancreatitis),and CA 19.9 serum level.The patient’s age and comorbidities should also be taken into consideration.Currently,there are different guidelines regarding the diagnosis and management of IPMNs.In this review,the following guidelines were presented:Sendai International Association of Pancreatology guidelines(2006),American Gastroenterological Association guidelines,revised international consensus Fukuoka guidelines(2012),revised international consensus Fukuoka guidelines(2017),and European evidence-based guidelines according to the European Study Group on Cystic Tumours of the Pancreas(2018).The Verona Evidence-Based Meeting 2020 was also presented and discussed.

Update on surgical treatment of pancreatic neuroendocrine neoplasms

Pancreatic neuroendocrine neoplasms(PNENs) are rare and account for only 2%-4% of all pancreatic neoplasms. All PNENs are potential(neurendocrine tumors PNETs) or overt(neuroendocrine carcinomas PNECs) malignant,but a subset of PNETs is low-risk. Even in case of low-risk PNETs surgical resection is frequently required to treat hormone-related symptoms and to obtain an appropriate pathological diagnosis. Low-risk PNETs in the body and the tail are ideal for minimallyinvasive approaches which should be tailored to the individual patient. Generally,surgeons must aim for parenchyma sparing in these cases. In high-risk and malignant PNENs,indications for tumor resection are much wider than for pancreatic adenocarcinoma,in many cases due to the relatively benign tumor biology. Thus,patients with locally advanced and metastatic PNETs may benefit from extensive resection. In experienced hands,even multi-organ resections are accomplished with acceptable perioperative morbidity and mortality rates and are associated with excellent long term survival. However,poorly differentiated neoplasms with high proliferation rates are associated with a dismal prognosis and may frequently only be treated with chemotherapy. The evidence on surgical treatment of PNENs stems from reviews of mostly singlecenter series and some analyses of nation-wide tumor registries. No randomized trial has been performed to compare surgical and non-surgical therapies in potentially resectable PNEN. Though such a trial would principally be desirable,ethical considerations and the heterogeneity of PNENs preclude realization of such a study. In the current review,we summarize recent advances in the surgical treatment of PNENs.

Survival comparison between primary hepatic neuroendocrine neoplasms and primary pancreatic neuroendocrine neoplasms and the analysis on prognosis-related factors

Background:Primary hepatic neuroendocrine neoplasms(PHNENs)are extremely rare and few articles have compared the prognosis of PHNENs with other neuroendocrine neoplasms(NENs).This study aimed to investigate the different prognosis between PHNENs and pancreatic NEN(Pan NENs)and evaluate the relevant prognosis-related factors.Methods:From January 2012 to October 2016,a total of 44 NENs patients were enrolled and divided into two groups according to the primary tumor location which were named group PHNENs(liver;n=12)and group Pan NENs(pancreas;n=32).Demographic,clinical characteristics and survival data were compared between the two groups with Kaplan-Meier method and log-rank tests.Prognostic factors were analyzed using the Cox regression model.Results:The overall survival of group PHNENs and group Pan NENs were 25.4±6.7 months and 39.8±3.7 months,respectively(P=0.037).The cumulative survival of group Pan NENs was significantly higher than that of group PHNENs(P=0.029).Univariate analysis revealed that sex,albumin,total bilirubin,total bile acid,aspartate aminotransferase,alkaline phosphatase,α-fetoprotein and carbohydrate antigen 19-9,histological types,treatments and primary tumor site were the prognostic factors.Further multivariate analysis indicated that albumin(P=0.008),histological types NEC(P=0.035)and treatments(P=0.005)were the independent prognostic factors.Based on the histological types,the cumulative survival of patients with well-differentiated neuroendocrine tumor was significant higher than that of patients with poorly differentiated neuroendocrine carcinoma in group PHNENs(P=0.022),but not in group Pan NENs(P>0.05).According to the different treatments,patients who received surgery had significantly higher cumulative survival than those with conservative treatment in both groups(P<0.05).Conclusions:PHNENs have lower survival compared to Pan NENs.Histological types and treatments affect the prognosis.Surgical resection still remains the first line of treatment for resectable lesions and can significantly improve the survival.