Surgical treatment of advanced-stage carcinoid tumors: lessons learned

Peritoneal metastases in patients with neuroendocrine neoplasms: a challenging site of metastases with clinical and prognostic implications

PURPOSE

Peritoneal metastases (PM) of neuroendocrine neoplasm (NEN) origin are identified with increasing frequency and exert a significant effect on quality of life and clinical status of the patients. The aim of this study was to identify the characteristics and the prognostic significance of PM in patients with NENs.

METHODS

A retrospective analysis of the data of patients from two tertiary referral centers was performed. We defined a control group of age- and gender-matched NEN patients with comparable stage IV disease but no PM.

RESULTS

We analysed 70 patients (41 females) with PM. Small intestine was the most common primary NEN site (87.1%). PM prevalence was 10.3%. Forty-four patients presented with synchronous PM, whereas 26 developed metachronous PM. The majority of patients had other concomitant metastases (50 hepatic, 6 lung and 12 bone metastases). Twelve patients developed intestinal obstruction. After PM diagnosis, 76% of patients received treatment with somatostatin analogues while six patients (8.6%) were treated with peptide receptor radionuclide therapy (PRRT). The median progression-free survival (PFS) in the PRRT-treated group was 15 months (95% CI 2-28). Median overall survival (OS) in the PM group was 142 months [95% CI 71-213] while it was not reached in the control group.

CONCLUSION

Peritoneal metastases show low prevalence among NEN patients and are most likely to develop in patients with small intestinal NENs and advanced metastatic disease. The presence of PM does seem to be associated with a negative prognostic impact on OS of NEN patients and their identification and prompt treatment is of major importance.

Surgery for advanced neuroendocrine tumours of the small bowel: recommendations based on a consensus meeting of the European Society of Endocrine Surgeons (ESES)

BACKGROUND

Small bowel neuroendocrine tumours often present with locally advanced or metastatic disease. The aim of this paper is to provide evidence-based recommendations regarding (controversial) topics in the surgical management of advanced small bowel neuroendocrine tumours.

METHODS

A working group of experts was formed by the European Society of Endocrine Surgeons. The group addressed 11 clinically relevant questions regarding surgery for advanced disease, including the benefit of primary tumour resection, the role of cytoreduction, the extent of lymph node clearance, and the management of an unknown primary tumour. A systematic literature search was performed in MEDLINE to identify papers addressing the research questions. Final recommendations were presented and voted upon by European Society of Endocrine Surgeons members at the European Society of Endocrine Surgeons Conference in Mainz in 2023.

RESULTS

The literature review yielded 1223 papers, of which 84 were included. There were no randomized controlled trials to address any of the research questions and therefore conclusions were based on the available case series, cohort studies, and systematic reviews/meta-analyses of the available non-randomized studies. The proposed recommendations were scored by 38-51 members and rated 'strongly agree' or 'agree' by 64-96% of participants.

CONCLUSION

This paper provides recommendations based on the best available evidence and expert opinion on the surgical management of locally advanced and metastatic small bowel neuroendocrine tumours.

Morbidity and Outcomes of Primary Tumor Management in Patients with Widely Metastatic Well-Differentiated Small Bowel Neuroendocrine Tumors

BACKGROUND

The benefit of primary tumor resection in distant metastatic small bowel neuroendocrine tumors (SBNETs) is controversial, with treatment-based morbidity not well-defined. We aimed to determine the impact of primary tumor resection on development of disease-specific complications in patients with metastatic well-differentiated SBNETs.

PATIENTS AND METHODS

A retrospective analysis was performed of patients diagnosed with metastatic well-differentiated jejunal/ileal SBNETs at a single tertiary care cancer center from 1980 to 2016. Outcomes were compared on the basis of treatment selected at diagnosis between patients who underwent initial medical treatment or primary tumor resection.

RESULTS

Among 180 patients, 71 underwent medical management and 109 primary tumor resection. Median follow-up was 116 months. Median event-free survival did not differ between treatment approaches (log-rank p = 0.2). In patients medically managed first, 16/71 (23%) required surgery due to obstruction, perforation, or bleeding. These same complications led to resection at presentation in 31/109 (28%) surgically treated patients. Development of an obstruction from the primary tumor was not associated with disease progression/recurrence (HR 1.14, 95% CI 0.75-1.75) with all patients recovering postoperatively. Ongoing tumor progression requiring secondary laparotomy was associated with worse mortality (HR 7.51, 95% CI 3.3-16.9; p < 0.001) and occurred in 20/109 (18%) primary tumor resection and 7/16 (44%) initially medically treated patients.

CONCLUSIONS

Rates of event-free survival among patients with metastatic SBNETs do not differ on the basis of primary tumor management. The development of an obstruction from the primary tumor was not associated with worse outcomes with all patients salvaged. Regardless of initial treatment selected, patients with metastatic SBNET should be closely followed for early signs of primary tumor complications.

Management Strategies and Outcomes for Small Intestinal Neuroendocrine Tumours with Involvement of the Superior Mesenteric Vessels: A Systematic Review

Small intestinal neuroendocrine tumours (SI-NETs) are the most common small intestinal tumours. A particularly challenging subset of these tumours is those that involve the superior mesenteric artery or vein for which the role and feasibility of surgery are often questioned. This systematic review aimed to identify and evaluate the management strategies used for these complex SI-NETs. The identified studies showed positive outcomes with surgery and multimodality therapy.

Imaging of Small-Bowel Neuroendocrine Neoplasms: AJR Expert Panel Narrative Review

Neuroendocrine neoplasms (NENs) of the small bowel are typically slow-growing lesions that remain asymptomatic until reaching an advanced stage. Imaging modalities for lesion detection, staging, and follow-up in patients with known or suspected NEN include CT enterography, MR enterography, and PET/CT using a somatostatin receptor analog. FDG PET/CT may have a role in the evaluation of poorly differentiated NENs. Liver MRI, ideally with a hepatocyte-specific contrast agent, should be used in the evaluation of hepatic metastases. Imaging informs decisions regarding both surgical approaches and systematic therapy (specifically, peptide receptor radionuclide therapy). This AJR Expert Panel Narrative Review describes the multimodality imaging features of small-bowel NENs; explores the optimal imaging modalities for their diagnosis, staging, and follow-up; and discusses how imaging may be used to guide therapy.

Small bowel neuroendocrine tumours - casting the net wide

PURPOSE OF REVIEW

Our aim is to provide an overview of small bowel neuroendocrine tumours (NETs), clinical presentation, diagnosis algorithm and management options. We also highlight the latest evidence on management and suggest areas for future research.

RECENT FINDINGS

Dodecanetetraacetic acid (DOTATATE) scan can detect NETs with an improved sensitivity than when compared with an Octreotide scan. It is complimentary to small bowel endoscopy that provides mucosal views and allows the delineation of small lesions undetectable on imaging. Surgical resection is the best management modality even in metastatic disease. Prognosis can be improved with the administration of somatostatin analogues and Evarolimus as second-line therapies.

SUMMARY

NETs are heterogenous tumours affecting most commonly the distal small bowel as single or multiple lesions. Their secretary behaviour can lead to symptoms, most commonly diarrhoea and weight loss. Metastases to the liver are associated with carcinoid syndrome.

Outcomes and survival in patients with advanced intestinal neuroendocrine tumours on home parenteral nutrition, an international multicentre retrospective cohort study

BACKGROUND AND AIMS

Only limited information is available on the use of home parenteral nutrition (HPN) in patients with advanced neuroendocrine tumours (NETs) causing intestinal failure (IF). This study aims to report the outcomes of the explore the use of HPN in this patient cohort, in the largest case series to date.

METHODS

A retrospective study in the United Kingdom and the Netherlands was performed, using the UK National British Artificial Nutrition Survey (BANS) and local databases in the Netherlands. Data regarding age, sex, NET grading, staging, treatment, HPN characteristics and survival outcomes were collected.

RESULTS

Data were collected on 41 patients (n = 18 males, 44%) with a median age of 65. Most primary tumours were in the small bowel (n = 35, 85%). The NETs were Grade 1 (n = 16, 39%), Grade 2 (n = 7, 17%), Grade 3 (n = 1, 2%). In 28 patients (n = 68%) there was stage IV disease with metastases located in the peritoneum, mesentery and or liver. There were two indications for HPN; short bowel syndrome (n = 27, 66%) and inoperable malignant bowel obstruction (n = 14, 34%). The median period on HPN was 11 months (interquartile range 4-25 months). 11 patients were still alive and receiving HPN treatment after 2 years, and 6 patients after 3 years. Six patients (22%) with short bowel syndrome (SBS) could be weaned from HPN. There was a statistically significant improved survival for patients with short bowel syndrome (median 24 months) compared to inoperable malignant bowel obstruction (median 7 months). The catheter-related bloodstream infection rate was comparable to other HPN patient cohorts at 1.0 per 1000 catheter days.

CONCLUSION

This study shows that HPN can be used safely in patients with NET and IF to increase survival beyond that reasonably expected in the context of either short bowel syndrome or inoperable malignant bowel obstruction. Patients with short bowel syndrome are most likely to benefit. Further prospective studies are necessary to validate survival benefits and to demonstrate the effect of HPN on quality of life.

Management of Metastatic GEPNETs

The chief causes of death of patients with GEPNETs are liver failure from hepatic replacement by tumor in the majority and bowel obstruction in the remainder. Many patients are with liver metastases are actually eligible for hepatic cytoreductive operations, even if they have numerous bilobar metastases and extra-hepatic disease, provided that greater than 70% of the liver tumor volume can be removed. This can often be done by combinations of parenchyma-sparing enucleations, wedge resections and radio frequency ablations. Patients with higher liver tumor burden can be treated with intra-arterial therapies, such as embolization and chemoembolization. Patients with peritoneal carcinomatosis are recommended to undergo cytoreductive operations including peritoneal stripping and bowel resections. Consensus guidelines by experts recommend bisphosphonate therapy for patients with bone metastases, reserving surgical treatment for patients with mechanical issues and/or potential spinal cord compression. Radiation can be employed for isolated painful metastases. PRRT may be an emerging therapy for treatment of bone metastases.

Anti-SSTR2 antibody-drug conjugate for neuroendocrine tumor therapy

Neuroendocrine (NE) tumors include a diverse spectrum of hormone-secreting neoplasms that arise from the endocrine and nervous systems. Current chemo- and radio-therapies have marginal curative benefits. The goal of this study was to develop an innovative antibody-drug conjugate (ADC) to effectively treat NE tumors (NETs). First, we confirmed that somatostatin receptor 2 (SSTR2) is an ideal cancer cell surface target by analyzing 38 patient-derived NET tissues, 33 normal organs, and three NET cell lines. Then, we developed a new monoclonal antibody (mAb, IgG1, and kappa) to target two extracellular domains of SSTR2, which showed strong and specific surface binding to NETs. The ADC was constructed by conjugating the anti-SSTR2 mAb and antimitotic monomethyl auristatin E. In vitro evaluations indicated that the ADC can effectively bind, internalize, release payload, and kill NET cells. Finally, the ADC was evaluated in vivo using a NET xenograft mouse model to assess cancer-specific targeting, tolerated dosage, pharmacokinetics, and antitumor efficacy. The anti-SSTR2 ADC exclusively targeted and killed NET cells with minimal toxicity and high stability in vivo. This study demonstrates that the anti-SSTR2 ADC has a high-therapeutic potential for NET therapy.

Dual-Targeted Extracellular Vesicles to Facilitate Combined Therapies for Neuroendocrine Cancer Treatment

Neuroendocrine (NE) cancers arise from cells within the neuroendocrine system. Chemotherapies and endoradiotherapy have been developed, but their clinical efficacy is limited. The objective of this study was to develop a dual-targeted extracellular vesicles (EV)-delivered combined therapies to treat NE cancer. Specifically, we produced EV in stirred-tank bioreactors and surface tagged both anti-somatostatin receptor 2 (SSTR 2) monoclonal antibody (mAb) and anti-C-X-C motif chemokine receptor 4 (CXCR4) mAb to generate mAbs-EV. Both live-cell confocal microscopy imaging and In Vivo Imaging System (IVIS) imaging confirmed that mAbs-EV specifically targeted and accumulated in NE cancer cells and NE tumor xenografts. Then the highly potent natural cytotoxic marine compound verrucarin A (Ver-A) with IC50 of 2.2-2.8 nM and microtubule polymerization inhibitor mertansine (DM1) with IC50 of 3.1-4.2 nM were packed into mAbs-EV. The in vivo maximum tolerated dose study performed in non-tumor-bearing mice indicated minimal systemic toxicity of mAbs-EV-Ver-A/DM1. Finally, the in vivo anticancer efficacy study demonstrated that the SSTR2/CXCR4 dual-targeted EV-Ver-A/DM1 is more effective to inhibit NE tumor growth than the single targeting and single drug. The results from this study could expand the application of EV to targeting deliver the combined potent chemotherapies for cancer treatment.

Comparing Deep Learning and Immunohistochemistry in Determining the Site of Origin for Well-Differentiated Neuroendocrine Tumors

Background

Determining the site of origin for metastatic well-differentiated neuroendocrine tumors (WDNETs) is challenging, and immunohistochemical (IHC) profiles do not always lead to a definitive diagnosis. We sought to determine if a deep-learning convolutional neural network (CNN) could improve upon established IHC profiles in predicting the site of origin in a cohort of WDNETs from the common primary sites.

Materials and Methods

Hematoxylin and eosin (H&E)-stained tissue microarrays (TMAs) were created using 215 WDNETs arising from the known primary sites. A CNN trained and tested on 60% (n = 130) and 40% (n = 85) of these cases, respectively. One hundred and seventy-nine cases had TMA tissue remaining for the IHC analysis. These cases were stained with IHC markers pPAX8, CDX2, SATB2, and thyroid transcription factor-1 (markers of pancreas/duodenum, ileum/jejunum/duodenum, colorectum/appendix, and lung WDNET sites of origin, respectively). The CNN diagnosis was deemed correct if it designated a majority or plurality of the tumor area as the known site of origin. The IHC diagnosis was deemed correct if the most specific marker for a particular site of origin met an H-score threshold determined by two pathologists.

Results

When all cases were considered, the CNN correctly identified the site of origin at a lower rate compared to IHC (72% vs. 82%, respectively). Of the 85 cases in the CNN test set, 66 had sufficient TMA material for IHC stains, thus 66 cases were available for a direct case-by-case comparison of IHC versus CNN. The CNN correctly identified 70% of these cases, while IHC correctly identified 76%, a finding that was not statistically significant (P = 0.56).

Conclusion

A CNN can identify WDNET site of origin at an accuracy rate close to the current gold standard IHC methods.

Positivity for SATB2 distinguishes Islet1 positive rectal neuroendocrine tumours from pancreaticoduodenal neuroendocrine tumours

AIMS

Determining the site of origin of a metastatic neuroendocrine tumour (NET) can be challenging and has important prognostic and therapeutic implications. An immunohistochemical (IHC) panel consisting of TTF1, CDX2, PAX8/PAX6 and Islet1 is often employed. However, there can be a significant IHC overlap among different primary sites. Herein, we sought to determine the utility of including Special AT-rich sequence binding protein-2 (SATB2) in the IHC panel that is used for determining the site of origin of a metastatic NET.

METHODS

Paraffin tissue microarrays consisting of 137 primary NETs (26 lung, 22 jejunoileal, 8 appendix, 5 stomach, 4 duodenum, 17 rectum and 55 pancreas) were stained for SATB2, in addition to the well-described lineage-associated markers, such as TTF1, CDX2, PAX6 and Islet1. Additionally, a tissue microarray consisting of 21 metastatic NETs (1 lung, 1 stomach, 8 jejunoileal and 11 pancreas) was stained for TTF1, CDX2, SATB2 and Islet1. The results were recorded as no staining, weak staining and moderate to strong staining.

RESULTS

All appendiceal NETs and majority (88%) of the rectal NETs were positive for SATB2. All primary foregut NETs (stomach, pancreas, duodenum and lung) were negative for SATB2, except for one pulmonary NET with weak staining. However, among the metastatic tumours, 5 of 11 pancreatic NETs, 1 stomach NET, 1 lung NET and 2 of 8 jejunoileal NETs showed weak staining. Receiver operating characteristic analysis incorporating sensitivity and specificity data of IHC panel, considering moderate to strong staining as truly positive cases, showed that inclusion of SATB2 to the previously described NET IHC panel outperformed the panel without SATB2, raising the specificity for pancreaticoduodenal NETs from 81.2% to 100%, with a positive predictive value (PPV) of 100% and negative predictive value (NPV) of 82.22% (p<0.0001); for appendiceal NETs the specificity changed from 99.1% to 98.5% and sensitivity increased from 11.8% to 80%, with a PPV and NPV of 66.67% and 99.26%, respectively (p<0.0001); and for rectal NETs the specificity increased from 97.6% to 99.3% and sensitivity raised from 7.1% to 66.7%, with a PPV and NPV of 80% and 98.53%, respectively (p<0.0001).

CONCLUSIONS

SATB2 stain is useful in differentiatingIslet1/PAX6 positive pancreatic and rectal NETs, as rectal NETs are typically moderately to strongly positive for SATB2 and pancreatic NETs are usually negative or weakly positive for SATB2. Moderate to strong staining for SATB2 is suggestive of an appendiceal or a rectal primary. SATB2 may complement the panel of CDX2, TTF1 and Islet1 in determining the site of origin of an NET in a metastatic setting.

Surgical Principles in the Management of Small Bowel Neuroendocrine Tumors

OPINION STATEMENT

Small bowel neuroendocrine tumors (SB NETs) are increasing in frequency and becoming more common in surgical practice. It is often difficult to make the diagnosis of a SB NET at an early stage, as the primary tumor tends to be small and patients are asymptomatic until there is regional or distant metastasis, when they develop abdominal pain, partial obstruction, or bleeding and/or develop carcinoid syndrome. Despite this advanced presentation at the time of diagnosis, patients with metastatic SB NETs, as compared to other gastrointestinal malignancies, have favorable survival, which can be improved by appropriate surgical interventions. With the lack of randomized studies, there is reasonable controversy surrounding the optimal management of patients with SB NETs. As such, treatment of these patients is driven primarily by physician experience and available data based predominantly on retrospective studies. Based on this, current recommendations advocate for patients with SB NETs (localized or metastatic) to be managed at experienced centers by a multidisciplinary team. Eligible patients should undergo surgical resection of primary and regional disease as outlined in this article. Additionally, patients with metastatic disease should be evaluated on a case by case basis to evaluate surgical options that may mitigate bowel symptoms (i.e., pain, intestinal angina, obstruction) and carcinoid symptoms (flushing, diarrhea, hemodynamic instability) and prolong survival. Unlike other gastrointestinal malignancies, aggressive surgical management of these patients, even in the context of unresectable metastatic disease, can improve patients' symptoms and long-term survival. The principles outlined in this article are geared to guide appropriate management of SB NET patients with improvement in quality of life and overall survival outcomes.

Surgical Management of Primary Small Bowel NET Presenting Acutely with Obstruction or Perforation

Up to 35% of small bowel neuroendocrine tumors (SBNETs) may present with an acute intra-abdominal complication including obstruction, perforation, bleeding or ischemia and may require emergency surgical treatment in centers not normally accustomed to managing patients with neuroendocrine tumors. These patients may have a known diagnosis of SBNET, be suspected as suffering from SBNET or have SBNET diagnosed as an incidental finding on presenting radiology or postoperative pathology. Perioperative priorities include obtaining both clinical and radiological staging with cross-sectional imaging and clinical examination, screening for the presence of carcinoid syndrome and right-sided cardiac disease and assessment of prognosis. Intraoperatively careful attention should be paid to noting the presence and location of multifocal primary and metastatic disease. Ideally, surgical resection with mesenteric lymph node dissection is the treatment of choice for obstructing and perforating lesions. Extended lymphadenectomy along the SMA, SMV and behind the pancreas should be primarily considered an elective procedure. In unwell patients with advanced disease surgical bypass (jejuno or ileocolic) or proximal defunctioning should be undertaken but, given the excellent long-term survivals in patients with stage IV disease, could be considered bridging procedures to elective resection following formal staging and multidisciplinary review.

Surgery and Perioperative Management in Small Intestinal Neuroendocrine Tumors

Small-intestinal neuroendocrine tumors (SI-NETs) are the most prevalent small bowel neoplasms with an increasing frequency. In the multimodal management of SI-NETs, surgery plays a key role, either in curative intent, even if R0 resection is feasible in only 20% of patients due to advanced stage at diagnosis, or palliative intent. Surgeons must be informed about the specific surgical management of SI-NETs according to their hormonal secretion, their usual dissemination at the time of diagnosis and the need for bowel-preserving surgery to avoid short bowel syndrome. The aim of this paper is to review the surgical indications and techniques, and perioperative and postoperative management of SI-NETs.

Medical Treatment of Advanced Pancreatic Neuroendocrine Neoplasms

Pancreatic neuroendocrine neoplasms (panNENs) are relatively rare but their incidence has increased almost sevenfold over the last four decades. Neuroendocrine neoplasms are classified according to their histologic differentiation and their grade. Their grade is based on their Ki-67 proliferation index and mitotic index. Their prognosis is highly variable according to these elements and treatments also vary according to their classification. Surgery is the only curative treatment for localized and advanced panNENs and offers a better prognosis than non-surgical treatments. In the case of an advanced panNEN without the possibility of resection and/or ablation, medical treatment remains the cornerstone for improving survival and preserving quality-of-life. PanNENs are considered as chemosensitive tumors, unlike midgut neuroendocrine tumors. Thus, panNENs can be treated with chemotherapy, but targeted therapies and somatostatin analogs are also treatment options. The scarcity and heterogeneity of NENs make their management difficult. The present review aims to clarify the medical treatments currently available for advanced panNENs, based on their characteristics, and to propose a treatment algorithm.

An Update on the Role of Immunohistochemistry in the Evaluation of Gastrointestinal Tract Disorders

As in other organ systems, immunohistochemistry (IHC) serves as an ancillary diagnostic tool for a wide variety of neoplastic and non-neoplastic disorders, including infections, work-up of inflammatory conditions, and subtyping neoplasms of the gastrointestinal (GI) tract. In addition, IHC is also used to detect a variety of prognostic and predictive molecular biomarkers for carcinomas of the GI tract. The purpose of this review is to highlight the use of IHC in common diagnostic scenarios throughout the tubular GI tract. The clinical indication and guidelines for performing IHC for detecting Helicobacter pylori is discussed along with role of gastrin and neuroendocrine markers in the diagnosis of autoimmune metaplastic atrophic gastritis. The major portion of this review discusses the use of IHC in the diagnostic workup of malignant neoplasms of the GI tract, such as adenocarcinoma versus squamous cell carcinoma, workup of poorly differentiated malignant neoplasms, and evaluation of uncommon gastric neoplasms (alpha-feto protein-producing carcinomas) and switch/sucrose-nonfermenting complex-deficient carcinomas. Lastly, localization of neuroendocrine tumors of unknown origin to aid clinical management, as well as HPV-driven anal neoplasia and IHC in the workup of basaloid anal neoplasms are also reviewed.

Prognostic Factors Associated With Progression for Advanced-Stage/G1 and G2 Small-Bowel Neuroendocrine Tumors After Multimodal Therapy: Experience From a Tertiary Referral Center

OBJECTIVES

Neuroendocrine tumors represent approximately 40% of primary small bowel malignancies. However, factors predictive of progression after multimodal surgical therapy have not been well described. We evaluated the characteristics of small bowel neuroendocrine tumor patients associated with progression after multimodal surgical resection.

METHODS

A retrospective chart review identified 99 stage III and stage IV small bowel neuroendocrine tumor patients at Mount Sinai diagnosed and treated with surgery between 2005 and 2019. Progression-free survival (PFS) was defined as time from surgery until progression in surveillance radiologic imaging. Kaplan-Meier method was used to calculate PFS. Cox proportional hazard models were used to study the prognostic factors for PFS.

RESULTS

Of 99 patients, 48 had tumor progression during the follow-up period. Median PFS was 5.7 years (95% confidence interval [CI], 3.73-8.66) for the entire cohort. Prognostic factors for PFS were age at diagnosis (hazard ratio [HR], 1.04; 95% CI, 1.01-1.07), perineural invasion (HR, 2.19; 95% CI, 1.13-4.23), and elevated preoperative chromogranin level (HR, 2.31; 95% CI, 1.01-5.27).

CONCLUSIONS

Age at diagnosis, perineural invasion, and elevated preoperative chromogranin level may play a prognostic role in PFS.

Case report: optimal tumor cytoreduction and octreotide with durable disease control in a patient with MEN-1 and Zollinger-Ellison syndrome-over a decade of follow-up

Background

Zollinger-Ellison syndrome (ZES) is a rare condition characterized by hypersecretion of gastrin by gastrinoma tumors leading to severe peptic ulcer disease with potential development of gastric carcinoid tumors. Herein, we report the clinical course of a 68-year-old patient with multiple endocrine neoplasia type 1 (MEN-1) who underwent several surgeries to ultimately undergo optimal tumor cytoreduction of locally advanced gastrinomas and symptomatic gastric carcinoids. The patient was subsequently maintained on octreotide long-acting release (LAR). This case report supports consideration for aggressive tumor cytoreduction and octreotide in similar patients with MEN-1-associated ZES for durable disease control and symptom management.

Case presentation

The patient is a 68-year-old male with multiple endocrine neoplasia type 1 (MEN-1), diagnosed in 1993 after presenting with recurrent renal calculi and hypercalcemia. Soon thereafter, he presented with symptoms and elevated gastrin levels suggestive of ZES prompting abdominal exploration with partial resection of the duodenum to remove gastrinoma tumor nodules. Within 4 years of the operation, he represented with intractable hypergastrinemia despite optimal medical management with peak gastrin levels exceeding 29,000 pg/mL, in 2006. In January 2007, the patient returned to the operating room for resection of regional peripancreatic and perigastric lymph nodes and enucleation of pancreatic body and tail gastrinoma tumors. Although his gastrin level decreased to 5000 pg/mL with resultant improvement of symptoms, in less than 2 years, he developed disease progression with obstructive symptomatology from enlarging gastric carcinoids and rising gastrin levels. In May of 2008, he underwent pancreaticoduodenectomy and near-total gastrectomy. Since June of 2008, the patient shows no demonstrable progression of disease and remains asymptomatic on LAR octreotide (30 mgs). Gastrin levels have been well controlled (range, 100–624 pg/mL; current 114 pg/mL).

Conclusion

Success of this procedure in our case report highlights the potential role for optimal tumor cytoreduction and LAR octreotide to control disease progression in a patient with MEN-I and Zollinger-Ellison syndrome with locally advanced gastrinoma and secondary large gastric carcinoids.

Defining the Supportive Care Needs and Psychological Morbidity of Patients With Functioning Versus Nonfunctioning Neuroendocrine Tumors: Protocol for a Phase 1 Trial of a Nurse-Led Online and Phone-Based Intervention

Background

Online information resources and support have been demonstrated to positively influence the well-being of people diagnosed with cancer. This has been explored in past literature for more common cancers; however, for rare cancers, such as neuroendocrine tumors (NETs), there are little to no support or resources available. Despite relatively good prognoses, the quality of life (QoL) of patients with NETs is significantly lower compared with samples of mixed cancer patients and the general population. Patients with NETs also typically report unclear and difficult pathways of disease management and treatment, given the heterogeneity of the diagnosis. There is a vital need to improve the availability of disease-specific information for this patient group and provide supportive care that is tailored to the unique needs of the NET patient population.

Objective

This study described the protocol of a study aimed to better understand the outcomes and experiences of patients diagnosed with NETs and to develop and pilot test a nurse-led online and phone-based intervention that will provide tailored supportive care targeted to NET subgroups (functioning vs nonfunctioning).

Methods

This is a multisite cohort with 3 phases, incorporating both quantitative and qualitative data collection. Phase 1 is a mixed methods prospective cohort study of NET patients identifying differences in patient experiences and priority of needs between NET subgroups. Phase 2 utilizes results from phase 1 to develop an online and nurse-led phone-based intervention. Phase 3 is to pilot test and evaluate the intervention’s acceptability, appropriateness, and feasibility.

Results

Currently, the project is progressing through phase 1 and has completed recruitment. A total of 138 participants have been recruited to the study. To date, patient-reported outcome data from 123 participants at baseline and 87 participants at 6-month follow-up have been collected. Of these, qualitative data from semistructured interviews from 35 participants have also been obtained. Phase 2 and phase 3 of the project are yet to be completed.

Conclusions

Limited research for patients with NETs suggests that QoL and patient experiences are significantly impaired compared with the general population. Furthermore, past research has failed to delineate how the clinical variability between those with functioning and nonfunctioning NETs impacts patient supportive care needs. This study will improve on the availability of disease-specific information as well as informing the design of a nurse-led online and phone-based supportive care intervention tailored for the unique needs of the NET patient population.

International Registered Report Identifier (IRRID)

DERR1-10.2196/14361

EndoVascular Occlusion and Tumor Excision (EVOTE): a Hybrid Approach to Small-Bowel Neuroendocrine Tumors with Mesenteric Metastases

BACKGROUND

Mesenteric metastases from small-bowel neuroendocrine tumors (SBNETs) present a surgical challenge due to encasement of mesenteric vessels. In this study, we evaluate the feasibility and safety of a new, hybrid surgical approach to these mesenteric masses, EndoVascular Occlusion and Tumor Excision (EVOTE).

METHODS

From 2014 to 2018, 13 patients underwent the EVOTE procedure after being referred to our institution for primary SBNETs with "unresectable" mesenteric metastases. During stage 1 of the hybrid EVOTE procedure, angiographic evaluation of the mesenteric mass is performed. If adequate collateralization is demonstrated, the encased mesenteric vessel(s) is embolized. Mass excision is performed the following day during stage 2 of the EVOTE procedure.

RESULTS

Preoperative embolization was successful in 86% of cases; 2 cases were aborted for persistent abdominal pain following occlusion testing. Complete surgical excision of the mesenteric mass was achieved in 86% of cases. The 30-day overall morbidity and mortality rate was 29% and 0%, respectively. There was one local recurrence at 31.8 months post-op; this patient underwent a repeat EVOTE procedure with successful complete excision.

DISCUSSION

EVOTE represents a new technique that aids in preoperative planning and surgical resection of SBNETs with mesenteric metastases.

Hepatic Resection for Non-functional Neuroendocrine Liver Metastasis: Does the Presence of Unresected Primary Tumor or Extrahepatic Metastatic Disease Matter?

OBJECTIVES

The objective of this study was to assess the impact of unresected primary tumor, as well as extrahepatic metastasis, on the long-term prognosis of patients undergoing hepatic resection for non-functional neuroendocrine liver metastasis (NF-NELM).

METHODS

Patients who underwent hepatic resection for NF-NELM were identified from a multi-institutional database. Data on clinical and pathological details, as well as the long-term overall survival (OS) were obtained and compared. Propensity score matching was performed to generate matched pairs of patients.

RESULTS

Among the 332 patients with NF-NELM, 281 (84.6%) underwent primary tumor resection, while 51 (15.4%) did not. Patients who underwent primary resection were more likely to have a pancreatic primary and metachronous NELM. The long-term OS of patients who did and did not have the primary neuroendocrine tumor (NET) resected was comparable on both unmatched (10-year survival rate 66.8% vs. 54.0%, p = 0.192) and matched (10-year survival rate 75.7% vs. 60.4%, p = 0.271) analyses. In contrast, patients with NF-NELM and extrahepatic metastasis had a worse OS following resection compared with patients who had intrahepatic-only metastasis on unmatched (10-year survival rate 37.5% vs. 69.3%, p = 0.002) and matched (10-year survival rate 37.5% vs. 86.3%, p = 0.011) analyses. On multivariable analysis, while resection of the primary NET was not associated with OS (hazard ratio [HR] 0.7, 95% confidence interval [CI] 0.4-1.2, p = 0.195), the presence of extrahepatic metastasis was independently associated with long-term risk of death (HR 3.9, 95% CI 1.7-9.2, p = 0.002).

CONCLUSIONS

While surgery should be considered for patients with NF-NELM who have an unresectable primary tumor, operative resection of NF-NELM may not be as beneficial in patients with extrahepatic disease.

Advances in the cytologic diagnosis of gastroenteropancreatic neuroendocrine neoplasms

Two-thirds of neuroendocrine neoplasms arising in the human body originate from the gastrointestinal system or pancreas. Gastroenteropancreatic neuroendocrine neoplasms are heterogeneous, comprising both well differentiated neuroendocrine tumors (NETs) and poorly differentiated neuroendocrine carcinomas (NECs). The clinical presentation, molecular characteristics, and behavior are distinct for NETs and NECs. Fine-needle aspiration is an important modality for the primary diagnosis and staging of these neoplasms and can provide information of prognostic and therapeutic significance. Our evolving understanding of neuroendocrine neoplasm biology has led to several iterations of classification. In this review, new concepts and issues most relevant to cytology diagnosis of gastroenteropancreatic neuroendocrine neoplasms are discussed, such as newer detection methods that aid in diagnosis and staging, recent changes in World Health Organization classification, practical issues related to grading these neoplasms on cytology, guidelines for diagnostic reporting, and panels of immunohistochemical stains for the diagnosis of metastasis. The current understanding of genetic and epigenetic events related to tumor development and potential applications for cytology also are presented as they relate to prognostication and recent therapeutic advances.

Surgical management of neuroendocrine tumor-associated liver metastases: a review

Liver metastasis is common among patients who suffer from neuroendocrine tumors (NETs). Radical surgery is the standard treatment whenever possible but there is still controversies concerning the treatment strategies such as resection of the primary, role of debulking surgery, liver transplantation (LT) and neoadjuvant or adjuvant therapies. This article aims to review the current evidence available, together with some latest updates, focusing on the surgical management.

Antineoplastic effects of histone deacetylase inhibitors in neuroendocrine cancer cells are mediated through transcriptional regulation of Notch1 by activator protein 1

Notch signaling is minimally active in neuroendocrine (NE) cancer cells. While histone deacetylase inhibitors (HDACi) suppress NE cancer growth by inducing Notch, the molecular mechanism underlying this interplay has not yet been defined. NE cancer cell lines BON, H727, and MZ-CRC-1 were treated with known HDACi Thailadepsin-A (TDP-A) and valproic acid (VPA), and Notch1 mRNA expression was measured with RT-PCR. Truncated genomic fragments of the Notch1 promotor region fused with luciferase reporter were used to identify the potential transcription factor (TF) binding site. The key regulatory TF was identified with the electrophoretic mobility shift assay (EMSA). The effect of HDACi on Notch1 level was determined before and after silencing the TF. TDP-A and VPA induced Notch1 mRNA in a dose-dependent manner. A functional DNA motif at -80 to -52 from the Notch1 start codon responsible for the HDACi-dependent Notch1 induction was identified. Mutation of this core sequence failed to induce luciferase activity despite HDACi treatment. EMSA showed the greatest gel shift with AP-1 in nuclear extracts. Knockdown of AP-1 significantly attenuated the effect of HDACi on Notch1 induction. Interestingly, AP-1 transfection did not alter Notch1 level, suggesting that AP-1 is necessary but insufficient for HDACi activation of Notch1. Therefore, AP-1 is the TF that binds to a specific transcription-binding site within the Notch1 promotor region to trigger Notch1 transcription. Elucidating the HDACi activation mechanism may lead to the development of novel therapeutic options against NE cancers and facilitate the identification of clinical responders and prevent adverse effects.

The Surgical Management of Small Bowel Neuroendocrine Tumors: Consensus Guidelines of the North American Neuroendocrine Tumor Society

Small bowel neuroendocrine tumors (SBNETs) have been increasing in frequency over the past decades, and are now the most common type of small bowel tumor. Consequently, general surgeons and surgical oncologists are seeing more patients with SBNETs in their practices than ever before. The management of these patients is often complex, owing to their secretion of hormones, frequent presentation with advanced disease, and difficulties with making the diagnosis of SBNETs. Despite these issues, even patients with advanced disease can have long-term survival. There are a number of scenarios which commonly arise in SBNET patients where it is difficult to determine the optimal management from the published data. To address these challenges for clinicians, a consensus conference was held assembling experts in the field to review and discuss the available literature and patterns of practice pertaining to specific management issues. This paper summarizes the important elements from these studies and the recommendations of the group for these questions regarding the management of SBNET patients.

Neuroendocrine Tumor-Targeted Upconversion Nanoparticle-Based Micelles for Simultaneous NIR-Controlled Combination Chemotherapy and Photodynamic Therapy, and Fluorescence Imaging

Although neuroendocrine tumors (NETs) are slow growing, they are frequently metastatic at the time of discovery and no longer amenable to curative surgery, emphasizing the need for the development of other treatments. In this study, multifunctional upconversion nanoparticle (UCNP)-based theranostic micelles are developed for NET-targeted and near-infrared (NIR)-controlled combination chemotherapy and photodynamic therapy (PDT), and bioimaging. The theranostic micelle is formed by individual UCNP functionalized with light-sensitive amphiphilic block copolymers poly(4,5-dimethoxy-2-nitrobenzyl methacrylate)-polyethylene glycol (PNBMA-PEG) and Rose Bengal (RB) photosensitizers. A hydrophobic anticancer drug, AB3, is loaded into the micelles. The NIR-activated UCNPs emit multiple luminescence bands, including UV, 540 nm, and 650 nm. The UV peaks overlap with the absorption peak of photocleavable hydrophobic PNBMA segments, triggering a rapid drug release due to the NIR-induced hydrophobic-to-hydrophilic transition of the micelle core and thus enabling NIR-controlled chemotherapy. RB molecules are activated via luminescence resonance energy transfer to generate 1O2 for NIR-induced PDT. Meanwhile, the 650 nm emission allows for efficient fluorescence imaging. KE108, a true pansomatostatin nonapeptide, as an NET-targeting ligand, drastically increases the tumoral uptake of the micelles. Intravenously injected AB3-loaded UCNP-based micelles conjugated with RB and KE108-enabling NET-targeted combination chemotherapy and PDT-induce the best antitumor efficacy.

Guidelines for the management of neuroendocrine tumours by the Brazilian gastrointestinal tumour group

Neuroendocrine tumours are a heterogeneous group of diseases with a significant variety of diagnostic tests and treatment modalities. Guidelines were developed by North American and European groups to recommend their best management. However, local particularities and relativisms found worldwide led us to create Brazilian guidelines. Our consensus considered the best feasible strategies in an environment involving more limited resources. We believe that our recommendations may be extended to other countries with similar economic standards.

Aggressive Surgical Approach to the Management of Neuroendocrine Tumors: A Report of 1,000 Surgical Cytoreductions by a Single Institution

BACKGROUND

Neuroendocrine tumors (NETs) are rare neoplasms. Our group has treated more than 2,000 NET patients and has performed more than 1,000 surgical cytoreductive procedures.

STUDY DESIGN

Records of 834 NET patients who underwent surgical cytoreduction at our institution were reviewed. Demographic information, intraoperative findings, extent of disease, complications, and survival rates were calculated.

RESULTS

Eight hundred patients underwent 1,001 cytoreductive operations. Sixty-five percent had small bowel primaries. One hundred and thirty-eight patients presented with an unknown primary site, which was localized intraoperatively in 89% of these cases. The intraoperative complication rate was 9%. The incidence of intraoperative carcinoid crisis was 1%. Mean ± SD operative time was 368 ± 146 minutes. Mean ± SD hospital stay was 9 ± 10 days. Minor postoperative complications occurred after 43% of procedures and major postoperative complications were noted after 19% of procedures. The 30-day postoperative mortality rate was 2%. Median overall survival (OS) for patients with pancreatic NETs was 124 months. The 5-, 10-, and 20-year OS rates for patients with pancreatic NETs were 67%, 51%, and 36%, respectively. The life expectancy difference (between OS and actuarial survival) after surgical cytoreduction for patients with pancreatic NETs was 16.6 years. Median OS for patients with small bowel NETs was 161 months. The 5-, 10-, and 20-year OS rates for patients with small bowel NETs were 84%, 67% and 31%, respectively. The life expectancy difference after surgical cytoreduction for patients with small bowel NETs was 11.7 years.

CONCLUSIONS

Surgical cytoreduction in NET patients has low morbidity and mortality rates and results in prolonged survival. We believe that surgical cytoreduction should play a major role in the care of patients with NETs.

Identification of primary tumors in patients presenting with metastatic gastroenteropancreatic neuroendocrine tumors

BACKGROUND

Patients with gastroenteropancreatic neuroendocrine tumors often present with metastases. Identification of the primary tumor is important for operative management, and therefore we sought to determine our success at identifying primary tumors with diagnostic testing and operative exploration.

METHODS

A clinical neuroendocrine tumor database was reviewed to identify patients presenting with metastases and primary tumor in situ. Results of radiologic, endoscopic, and operative procedures were evaluated to determine which correctly identified the primary tumor.

RESULTS

There were 197 patients presenting with metastases and unresected primaries, 134 who had an operation and 63 managed nonoperatively. Primaries were identified preoperatively in 168 (84%), at operative exploration in 7, and were not found in 22 patients. Computed tomography found 150/197 primary tumors, somatostatin-receptor scintigraphy 88/155, and endoscopy 43/107. The sensitivity of computed tomography surpassed scintigraphy (76% vs 57%, P < .01). The primary was removed in 130/134 (97%) patients, and hepatic debulking was performed in 67%. Median survival for operative patients with small bowel and pancreatic tumors was 145 and 71 months, respectively.

CONCLUSION

Imaging and endoscopy identified the primary tumor in most patients, and the majority of the others were found at exploration. Preoperative testing facilitated operative planning, allowing for resection of the primary and hepatic debulking in most patients.

Resection of primary gastroenteropancreatic neuroendocrine tumors in the presence of irresectable liver metastases

Gastroenteropancreatic neuroendocrine tumors often present at an advanced stage and carry a variable prognosis, with many patients living long periods even with metastatic disease. Resection of the primary tumor when liver metastases are unresectable is a contentious subject with no consensus between existing guidelines. A number of recent studies have suggested a potential survival benefit as well as improved symptom control with resection. With variable results from nonoperative management strategies, the risk:benefit ratio of resection of the primary tumor may be favorable for carefully selected patients.

AACE/ACE disease state clinical review: diagnosis and management of midgut carcinoids

OBJECTIVE

Neuroendocrine tumors (NETs) are a collection of complex tumors that arise from the diffuse endocrine system, primarily from the digestive tract. Carcinoid tumors most commonly originate from the small intestine. These tumors are either referred to as small intestinal neuroendocrine tumors or midgut carcinoids (MGCs). The purpose of this review article is to survey the diagnostic and therapeutic pathways for patients with MGC and provide an overview of the complex multidisciplinary care involved in improving their quality of life, treatment outcomes, and survival.

METHODS

The current literature regarding the diagnosis and management of MGCs was reviewed.

RESULTS

Dry flushing and secretory diarrhea are the hallmarks of the clinical syndrome of MGC. Managing MGC requires attention to the overall symptom complex, including the physical effects of the tumor and biomarker levels. The somatostatin analogs (SAs) octreotide and lanreotide are highly efficacious for symptomatic improvement. MGCs require resection to encompass the primary tumor and mesenteric lymph node metastases and should include cholecystectomy if the patient is likely to receive SA therapy. Debulking of liver metastasis by resection in combination with ablative therapies and other liver-directed modalities may help palliate symptoms and hormonal overproduction in carefully selected patients. Quality of life is an important measure of patients' perception of the burden of their disease and impact of treatment modalities and may be a useful guide in deciding changes in therapy to alter apparent health status.

CONCLUSION

MGC is a challenging malignancy that requires the input of a multidisciplinary team to develop the best treatment plan. Consultation with expert centers that specialize in NETs may also be indicated for complex cases. With expert care, patients can be cured or live with the disease and enjoy good quality of life.

Single-incision laparoscopic resection of small bowel tumours: Making it easier for patient and surgeon

BACKGROUND:

Patients with small bowel tumours frequently require surgical intervention. Minimally invasive techniques require advanced skills and may not be offered to many patients. We present a laparoscopic single-incision technique that is minimally invasive without requiring intracorporeal anastomosis.

MATERIALS AND METHODS:

The cases of all patients with laparoscopic small bowel resections performed by one surgeon from 2008 to 2012 were reviewed. A single-port technique was introduced after it became available at our institution in 2009. Before that, conventional laparoscopy (LAP) was performed with extension of the periumbilical incision to allow externalisation of the bowel.

RESULTS:

Totally, 10 patients were identified who underwent laparoscopic resection of small bowel tumours: 9 in the small bowel and 1 in the terminal ileum near the cecum. Three tumours were resected before 2009 using LAP, and 7 were resected using the single-port technique. Median length of stay was 3 days, median follow-up was 16.5 months, and no patients had a recurrence. Operative time, post-operative complications, hospital length of stay, and narcotic utilisation were similar between the single-port and traditional laparoscopic groups.

CONCLUSION:

Laparoscopic removal of small bowel tumours with a small, periumbilical trocar incision is both effective and feasible without advanced technical skill.

The experience of a referral centre and literature overview of GIST and carcinoid tumours in inflammatory bowel diseases

Patients suffering from Inflammatory Bowel Diseases (IBD) are at increased risk of developing cancers of the gastrointestinal tract (GI). Adenocarcinomas are the most commonly observed GI tumours in IBD, and occur through an in inflammation-driven pathway. A trend toward reduced risk of bowel cancers has been observed in IBD in recent years, presumably related to improved medical treatments. However, some cancers may be independent from active inflammation, probably originating from altered interactions between the extremely active immune system of IBD patients and environmental factors. Data concerning gastrointestinal stromal tumours (GIST) and carcinoids tumours (CaT) of the GI in IBD patients are scanty. We report our experience with these rare cancers, and provide the readers with an overview on the topic, focussing on distinguishing and peculiar features of GIST and CaT of the GI in IBD compared with other cancer types and with general population, and address the treatment of such challenging conditions. Available data do not support an increased risk of GIST in IBD patients, but GI CaT may be more commonly observed in Crohn's disease. However, the presentation of GIST and GI CaT is protean and does not seem to be associated with disease activity in the involved GI segment in IBD. Conversely, some evidences suggest a potential role of inflammation in sustaining GI CaT in IBD. Increased awareness, longer duration of disease, and improved diagnostic modalities should also be considered when evaluating the increasing trend of CaT in CD patients. Treatment of GIST and CaT is not dissimilar from that of non-IBD patients, but prompt suspicion and diagnosis are crucial to achieve optimal outcomes.

[Rectal neuroendocrine tumors: surgical therapy]

The incidence of rectal neuroendocrine tumors (NET) has increased in recent years. Most of these neoplasms are asymptomatic and are diagnosed by colonoscopy screening, which could be one of the reasons for the increasing occurrence. As less than 1 % of rectal NET produce serotonin they are practically never discovered due to a carcinoid syndrome. The current guidelines of the European (ENETS) and North American (NANETS) Neuroendocrine Tumor Societies support clinicians with useful diagnostic and treatment algorithms. The most important criteria for therapy are tumor size and histopathological risk factors for metastases. For well-differentiated rectal neuroendocrine neoplasms < 1 cm, local endoscopic or surgical excision is recommended. Due to the lack of evidence tumors sized 1-2 cm represent a grey area for prognosis and treatment. All NET > 1.5 cm must be excised by radical surgery as low anterior rectal resection or abdominoperineal extirpation with total mesorectal excision (TME). Resectable liver and lung metastases of well-differentiated NETs should be surgically treated with curative intent.

Safety and Efficacy of 68Ga-DOTATATE PET/CT for Diagnosis, Staging, and Treatment Management of Neuroendocrine Tumors

Our purpose was to evaluate the safety and efficacy of (68)Ga-DOTATATE PET/CT compared with (111)In-pentetreotide imaging for diagnosis, staging, and restaging of pulmonary and gastroenteropancreatic neuroendocrine tumors.

METHODS

(68)Ga-DOTATATE PET/CT and (111)In-pentetreotide scans were obtained for 78 of 97 consecutively enrolled patients with known or suspected pulmonary or gastroenteropancreatic neuroendocrine tumors. Safety and toxicity were measured by comparing vital signs, serum chemistry values, or acquisition-related medical complications before and after (68)Ga-DOTATATE injection. Added value was determined by changes in treatment plan when (68)Ga-DOTATATE PET/CT results were added to all prior imaging, including (111)In-pentetreotide. Interobserver reproducibility of (68)Ga-DOTATATE PET/CT scan interpretation was measured between blinded and nonblinded interpreters.

RESULTS

(68)Ga-DOTATATE PET/CT and (111)In-pentetreotide scans were significantly different in impact on treatment (P < 0.001). (68)Ga-DOTATATE PET/CT combined with CT or liver MRI changed care in 28 of 78 (36%) patients. Interobserver agreement between blinded and nonblinded interpreters was high. No participant had a trial-related event requiring treatment. Mild, transient events were tachycardia in 1, alanine transaminase elevation in 1, and hyperglycemia in 2 participants. No clinically significant arrhythmias occurred. (68)Ga-DOTATATE PET/CT correctly identified 3 patients for peptide-receptor radiotherapy incorrectly classified by (111)In-pentetreotide.

CONCLUSION

(68)Ga-DOTATATE PET/CT was equivalent or superior to (111)In-pentetreotide imaging in all 78 patients. No adverse events requiring treatment were observed. (68)Ga-DOTATATE PET/CT changed treatment in 36% of participants. Given the lack of significant toxicity, lower radiation exposure, and improved accuracy compared with (111)In-pentetreotide, (68)Ga-DOTATATE imaging should be used instead of (111)In-pentetreotide imaging where available.

Role of Staging in Patients with Small Intestinal Neuroendocrine Tumours

Small bowel neuroendocrine tumours are the commonest malignancy arising in the small intestine and have substantially increased in incidence in recent decades. Patients with small bowel neuroendocrine tumours commonly develop lymph node and/or distant metastases. Here, we examine the role of staging in 84 surgically treated patients with small bowel neuroendocrine tumours, comparing diagnostic information yielded from morphological, functional and endoscopic modalities. Furthermore, we correlate pre-operative staging with intra-operative findings in a sub-cohort of 20 patients. The vast majority of patients had been histologically confirmed to have low-grade (Ki-67 <2%) disease; however, lymph node and distant metastases were observed in 74 (88.1%) and 51 (60.7%) of patients at presentation, respectively. Liver metastases were evident in 48 (57.1%) patients, with solely peritoneal and bone metastases observed in 2 (2.4%) and 1 (1.2%) patients, respectively. Forty patients (47.6%) received multimodal treatment. In our sub-cohort analysis, pre-operative imaging understaged disease in 14/20 (70%) when compared with intra-operative findings. In patients with multifocal primary tumours and miliary liver metastases, no imaging modality was able to detect entire disease spread. Overall, presently available imaging modalities heavily underestimate disease stage, with meticulous intra-operative abdominal examination being superior to any imaging technology. Multimodal treatment has an important role in prolonging survival.

Liver-directed surgery of neuroendocrine metastases: What is the optimal strategy?

INTRODUCTION

Neuroendocrine tumors (NETs) frequently metastasize to the liver. Operative debulking offers symptomatic relief and improved survival; however, the frequent presence of multifocal, bilobar disease and high recurrence rates introduces doubt regarding their optimal management. Parenchyma-sparing debulking (PSD) procedures (ablation, enucleation, wedge resections) may offer similar survival improvements as resection while minimizing morbidity and preserving functional liver tissue.

METHODS

Clinicopathologic variables from 228 patients with small bowel or pancreatic NETs managed operatively at one institution were collected. Liver-directed surgery was carried out when substantial debulking was deemed feasible. Survival was assessed by use of the Kaplan-Meier method.

RESULTS

A total of 108 patients with pancreatic NET or small bowel NET underwent liver-directed surgery with primarily PSD procedures. Nearly two-thirds of patients achieved 70% cytoreduction and 84% had concurrent resection of their primary. The median number of lesions treated was 6 (range, 1-36). There were no 30-day operative mortalities. The 30-day major complication rate was 13.0%. Patients who achieved 70% cytoreduction enjoyed improved progression free (median 3.2 years) and overall survival (median not reached).

CONCLUSION

PSD procedures are safe and can achieve significant cytoreduction, which is associated with improved survival. Lowering the debulking target threshold to 70% may benefit NET patients by increasing eligibility for cytoreduction.

Problems with the diagnosis of metastatic neuroendocrine neoplasms. Which diagnostic criteria should we use to determine tumor origin and help guide therapy?

Neuroendocrine neoplasms (NENs) can often present with metastatic disease before the primary tumor is discovered. Metastatic lesions are generally classified as well differentiated and poorly differentiated for prognostic and therapeutic purposes. In addition, for well-differentiated neuroendocrine tumors (WDNETs), pathologists are expected to determine the site of origin, if not already known, and grade the tumors. However, it is often difficult for pathologists to provide this information with certainty without knowing the site of tumor origin, as different criteria have been proposed by WHO for classification of gastrointestinal and pulmonary NENs. In this review, we will discuss the current classification and grading schema of NENs and their impact on clinical care, the differential diagnosis of NENs, the use of immunohistochemical stains that help identify tumor site of origin, and a proposed approach for the diagnosis and classification of metastatic NENs.

Small intestinal neuroendocrine tumors with liver metastases and resection of the primary: Prognostic factors for decision making

INTRODUCTION

Patients with small intestine neuroendocrine tumors present with liver metastases in 50-75% of cases at diagnosis. The aim of the present study was to assess prognostic factors in patients with liver metastases from intestinal neuroendocrine tumor after primary tumor surgical removal with or without liver surgery or radiofrequency ablation. The primary endpoint was disease-specific survival.

METHODS

Data regarding seventy-eight consecutive patients with liver metastases who undergone primary tumor surgical removal between 1996 and 2011 were extracted from the institutional tumor registry and retrospectively analyzed.

RESULTS

Liver tumor burden was <25% in 43 (55.1%) 25-50% in 30 (38.5%) and >50% in 5 (6.4%) patients. For the whole cohort of patients disease-specific survival at 3, 5 and 8 years was 93.2%, 83.6% and 77.3%, respectively. Fifteen patients who underwent radical liver surgery were all alive with a median survival of 106 months (range 18-152 months). In multivariate analysis the Ki-67 index in a continuous fashion significantly correlate with prognosis (p = 0.021). Liver tumor burden (p = 0.036) and extrahepatic involvement (p = 0.03), were the most powerful prognosticators for patients who underwent only debulking surgery.

CONCLUSION

The Ki-67 index, the liver tumor burden and the presence of extrahepatic metastases should be carefully considered in the selection criteria for liver debulking in asymptomatic patients.

Liver metastases of small intestine neuroendocrine tumors: Ki-67 heterogeneity and World Health Organization grade discordance with primary tumors

OBJECTIVES

We examined Ki-67 heterogeneity within single and between synchronous liver metastases of small intestine neuroendocrine tumors.

METHODS

There were 27 patients (10 men and 17 women) with two or more liver metastases. The Ki-67 index was used to classify the tumors into World Health Organization grade 1, 2, or 3. The association between Ki-67 heterogeneity and tumor size of liver metastases was analyzed. Correlation of tumor grade with patient survival was also evaluated.

RESULTS

Primary tumors from 20 patients were graded, including 17 grade 1 and three grade 2. A total of 188 liver metastases were resected, including 122 (65%) grade 1, 47 (25%) grade 2, and 19 (10%) grade 3. The highest tumor grade was grade 1 in 10 (37%), grade 2 in nine (33%), and grade 3 in eight (30%) patients. Patients with one or more grade 3 liver lesions had a shorter progression-free survival compared with those with grade 1/2 tumors (P < .001). A positive association was found between tumor size and Ki-67 index (P = .04), as well as between tumor size and intratumoral Ki-67 heterogeneity (P < .001).

CONCLUSIONS

Intratumoral and intertumoral Ki-67 heterogeneity is common and positively correlated with tumor size. The presence of one or more grade 3 liver lesions predicts a worse prognosis.