A phase II trial of irinotecan and cisplatin in patients with metastatic neuroendocrine tumors

Imaging of Neuroendocrine Neoplasms; Principles of Treatment Strategies. What Referring Clinicians Want to Know

ABSTRACT

Neuroendocrine neoplasms (NENs) are a diverse group of tumors that express neuroendocrine markers and primarily affect the lungs and digestive system. The incidence of NENs has increased over time due to advancements in imaging and diagnostic techniques. Effective management of NENs requires a multidisciplinary approach, considering factors such as tumor location, grade, stage, symptoms, and imaging findings. Treatment strategies vary depending on the specific subtype of NEN. In this review, we will focus on treatment strategies and therapies including the information relevant to clinicians in order to undertake optimal management and treatment decisions, the implications of different therapies on imaging, and how to ascertain their possible complications and treatment effects.

The Surgical Management of Lung Neuroendocrine Neoplasms

This review summarizes key recent developments relevant to the surgical management of lung neuroendocrine neoplasms (L-NENs), including typical and atypical carcinoids, large cell neuroendocrine carcinoma, and small cell lung carcinoma. This review includes recent insights into the classification, clinical presentation, diagnostic workup, treatment options, and follow-up. Highlighted topics include general principles of surgery in localized or locally advanced or metastatic L-NENs, lung-sparing surgery for small, peripheral typical carcinoids, adjuvant and systemic therapies for typical and atypical carcinoids, and surgery and adjuvant therapies for large cell neuroendocrine carcinoma and small cell lung carcinoma.

Effectiveness of Etoposide and Cisplatin vs Irinotecan and Cisplatin Therapy for Patients With Advanced Neuroendocrine Carcinoma of the Digestive System: The TOPIC-NEC Phase 3 Randomized Clinical Trial

Question

For patients with advanced neuroendocrine carcinoma of the digestive system, which of the 2 community standard regimens is more effective: etoposide plus cisplatin (EP) or irinotecan plus cisplatin (IP)?

Findings

In this randomized clinical trial of 170 patients who were chemotherapy naive and had recurrent or unresectable neuroendocrine carcinoma of the digestive system, median overall survival was 12.5 months in the EP arm and 10.9 months in the IP arm.

Meaning

Both EP and IP therapy remain standard first-line chemotherapy options.

Importance

Etoposide plus cisplatin (EP) and irinotecan plus cisplatin (IP) are commonly used as community standard regimens for advanced neuroendocrine carcinoma (NEC).

Objective

To identify whether EP or IP is a more effective regimen in terms of overall survival (OS) in patients with advanced NEC of the digestive system.

Design, Setting, and Participants

This open-label phase 3 randomized clinical trial enrolled chemotherapy-naive patients aged 20 to 75 years who had recurrent or unresectable NEC (according to the 2010 World Health Organization classification system) arising from the gastrointestinal tract, hepatobiliary system, or pancreas. Participants were enrolled across 50 institutions in Japan between August 8, 2014, and March 6, 2020.

Interventions

In the EP arm, etoposide (100 mg/m²/d on days 1, 2, and 3) and cisplatin (80 mg/m²/d on day 1) were administered every 3 weeks. In the IP arm, irinotecan (60 mg/m²/d on days 1, 8, and 15) and cisplatin (60 mg/m²/d on day 1) were administered every 4 weeks.

Main Outcomes and Measures

The primary end point was OS. In total, data from 170 patients were analyzed to detect a hazard ratio (HR) of 0.67 (median OS of 8 and 12 months in inferior and superior arms, respectively) with a 2-sided α of 10% and power of 80%. The pathologic findings were centrally reviewed following treatment initiation.

Results

Among the 170 patients included (median [range] age, 64 [29-75] years; 117 [68.8%] male), median OS was 12.5 months in the EP arm and 10.9 months in the IP arm (HR, 1.04; 90% CI, 0.79-1.37; P = .80). The median progression-free survival was 5.6 (95% CI, 4.1-6.9) months in the EP arm and 5.1 (95% CI, 3.3-5.7) months in the IP arm (HR, 1.06; 95% CI, 0.78-1.45). A subgroup analysis of OS demonstrated that EP produced more favorable OS in patients with poorly differentiated NEC of pancreatic origin (HR, 4.10; 95% CI, 1.26-13.31). The common grade 3 and 4 adverse events in the EP vs IP arms were neutropenia (75 of 82 [91.5%] patients vs 44 of 82 [53.7%] patients), leukocytopenia (50 of 82 [61.0%] patients vs 25 of 82 [30.5%] patients), and febrile neutropenia (FN) (22 of 82 [26.8%] patients vs 10 of 82 [12.2%] patients). While incidence of FN was initially high in the EP arm, primary prophylactic use of granulocyte colony-stimulating factor effectively reduced the incidence of FN.

Conclusions and Relevance

Results of this randomized clinical trial demonstrate that both EP and IP remain the standard first-line chemotherapy options. Although AEs were generally manageable, grade 3 and 4 AEs were more common in the EP arm.

Trial Registration

Japan Registry of Clinical Trials: jRCTs031180005; UMIN Clinical Trials Registry: UMIN000014795

Therapeutic strategies for gastroenteropancreatic neuroendocrine neoplasms: State-of-the-art and future perspectives

Although gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) have always been considered rare tumors, their incidence has risen over the past few decades. They represent a highly heterogeneous group of neoplasms with several prognostic factors, including disease stage, proliferative index (Ki67), and tumor differentiation. Most of these neoplasms express somatostatin receptors on the cell surface, a feature that has important implications in terms of prognosis, diagnosis, and therapy. Although International Guidelines propose algorithms aimed at guiding therapeutic strategies, GEP-NEN patients are still very different from one another, and the need for personalized treatment continues to increase. Radical surgery is always the best option when feasible; however, up to 80% of cases are metastatic upon diagnosis. Regarding medical treatments, as GEP-NENs are characterized by relatively long overall survival, multiple therapy lines are adopted during the lifetime of these patients, but the optimum sequence to be followed has never been clearly defined. Furthermore, although new molecular markers aimed at predicting the response to therapy, as well as prognostic scores, are currently being studied, their application is still far from being part of daily clinical practice. As they represent a complex disease, with therapeutic protocols that are not completely standardized, GEP-NENs require a multidisciplinary approach. This review will provide an overview of the available therapeutic options for GEP-NENs and attempts to clarify the possible approaches for the management of these patients and to discuss future perspectives in this field.

Efficacy of Immune Checkpoint Inhibitors against Advanced or Metastatic Neuroendocrine Neoplasms: A Systematic Review and Meta-Analysis

We performed a systematic review and meta-analysis of the treatment efficacy of immune checkpoint inhibitors (ICIs) in advanced/metastatic neuroendocrine neoplasms (NENs). MEDLINE and EMBASE were searched to identify studies that provide data on treatment response and/or survival outcomes of advanced/metastatic NEN patients treated with ICIs. The overall response rate (ORR) was pooled using a random-effects model. Meta-regression was performed to explore factors influencing the ORR. Individual patient data (IPD) meta-analysis of survival was performed using stratified Cox regression. Ten studies (464 patients) were included. The overall pooled ORR was 15.5% (95% confidence interval (CI), 9.5-24.3%), and it varied according to the primary site (thoracic, 24.7%; gastro-entero-pancreatic, 9.5%), tumor differentiation (poorly differentiated, 22.7%; well-differentiated, 10.4%), and drug regimen (combination, 25.3%; monotherapy, 10.1%). All these variables significantly influenced the ORR. Tumor differentiation was associated with both overall survival and progression-free survival (hazard ratio of poorly differentiated tumors, 4.2 (95% CI, 2.0-8.7) and 2.6 (95% CI, 1.6-4.4), respectively). Thus, the treatment efficacy of ICIs for advanced/metastatic NENs varied according to primary site, tumor differentiation, and drug regimen. Poorly differentiated NENs showed a better ORR than well-differentiated NENs but had a negative impact on survival.

Should temozolomide be used on the basis of O6-methylguanine DNA methyltransferase status in patients with advanced neuroendocrine tumors? A systematic review and meta-analysis

BACKGROUND

Temozolomide (TEM) is an active treatment in metastatic neuroendocrine tumors (NETs). Patients affected by glioblastoma multiforme or advanced melanoma treated with TEM who have deficiency of O⁶-methylguanine DNA methyltransferase (MGMT) have a better responses and survival. However, the predictive role of MGMT in patients with NETs treated with TEM is still debated.

METHODS

We conducted a systematic review of the literature and meta-analysis, based on PRISMA methodology, searching in the main databases (PubMed, Embase, Scopus, Web of Science, Cochrane Library and clinical trial.gov) and the proceedings of the main international congresses, until April 26, 2021.

RESULTS

Twelve out of 616 articles were selected for our analysis, regarding a total of 858 NET patients treated with TEM-based chemotherapy. The status of MGMT had been tested in 513 (60%) patients, using various methods. The pooled overall response rate (ORR) was higher in MGMT-deficient compared with MGMT-proficient NETs, with a risk difference of 0.31 (95% confidence interval, CI: 0.13-0.50; p < 0.001; I²: 73%) and risk ratio of 2.29 (95% CI: 1.34-3.91; p < 0.001; I²: 55%). The pooled progression free survival (PFS) (hazard ratio, HR = 0.56; 95% CI: 0.43-0.74; p < 0.001) and overall survival (OS) (HR = 0.41; 95% CI: 0.20-0.62; p = 0.011) were longer in MGMT-deficient versus MGMT-proficient NETs.

CONCLUSIONS

Our meta-analysis suggested that MGMT status may be predictive of TEM efficacy. However, due to the high heterogeneity of the evaluated studies the risk of biases should be considered. On this hypothesis future homogeneous prospective studies are warranted.

State of the art and future directions in the systemic treatment of neuroendocrine neoplasms

PURPOSE OF REVIEW

Neuroendocrine neoplasms (NENs) are rare and heterogeneous malignancies whose natural evolution may be defined according to various prognostic factors, including localization of the primitive tumour, hormone secretory status, histological grade, tumour burden, tumour growth rate, expression of somatostatin receptors and fluorodeoxyglucose-avidity. The treatment of these tumours in an advanced setting is based on relatively little robust data.

RECENT FINDINGS

A recent pathological classification introduced a new category of high-grade but well differentiated neuroendocrine tumours (NET G3), with markedly different behaviour from neuroendocrine carcinomas (NECs). Yet, the optimal treatment of those tumours is still uncertain. Advances are needed in molecular subtyping of NENs to understand better their heterogeneity and inform personalized therapies.

SUMMARY

The current review summarizes the current knowledge, indicates some exciting future directions and outlines the most interesting ongoing clinical trials likely to impact current practice.

FOLFIRINEC: a randomized phase II trial of mFOLFIRINOX vs platinum-etoposide for metastatic neuroendocrine carcinoma of gastroenteropancreatic or unknown origin

BACKGROUND

Poorly differentiated neuroendocrine carcinomas (NEC) are rare diseases with a poor prognosis. Platinum-etoposide (PE) has been the recommended first-line treatment for decades. FOLFIRINEC (NCT04325425) is a national multicenter randomized phase II study which aims to challenge this standard regimen.

METHODS

The primary objective is to compare the median progression-free survival (PFS) under mFOLFIRINOX versus PE. The secondary objectives are to evaluate the objective response rates (ORR), median overall survival (OS), safety and quality of life. The associated real-time translational study will establish a molecular profile for each patient enrolled.

MAIN INCLUSION CRITERIA ARE

NEC of gastroenteropancreatic (GEP) or unknown origin, metastatic and RECIST 1.1 evaluable disease, tumor sample available and no contraindication to chemotherapy. Patients will be randomized 1:1 between PE every 21 days for 6-8 cycles and mFOLFIRINOX every 14 days for up to 12 cycles and stratified according to center, performance status, Ki67 and pathological subtype. This trial will randomize 218 patients (24 months of follow-up) to have 80% power to detect an improvement of the median PFS from 5 months under PE to 7.5 months under mFOLFIRINOX (HR of 0.67, α =5%, two-sided). An intermediate analysis is planned at 50% of events. Recruitment started on October 20, 2020.

Systemic Treatment of Advanced Gastroenteropancreatic Neuroendocrine Tumors in Korea: Literature Review and Expert Opinion

Neuroendocrine tumors (NETs) are a group of malignancies arising from neuroendocrine cells and frequently originate in the gastrointestinal tract and pancreas. Although curative resection is the main treatment for localized disease, systemic therapy is needed for relapsed or metastatic/unresectable gastroenteropancreatic NETs (GEP-NETs). Although there are several NET treatment guidelines from various countries, the geographical discrepancies between patient clinical characteristics, the regulatory approval status for therapeutic agents, and medical practices necessitate specific guidelines for Korean patients. We here provide a consensus review of the diagnosis, staging and systemic treatment of Korean GEP-NET patients. Systemic therapy options and the current Korean expert consensus on these treatments, including somatostatin analogs, targeted therapies such as everolimus and sunitinib, peptide receptor radionuclide treatments, and cytotoxic chemotherapies are addressed.

Mediastinal Neuroendocrine Carcinoma Slowly Growing for 8 Years after Surgical Resection of Esophageal Squamous Cell Carcinoma

A 70-year-old woman was referred to our department due to a solitary mediastinal tumor which gradually grew near the site of anastomosis for 8 years after radical surgery of esophageal squamous cell carcinoma. It was difficult to distinguish the lymph node recurrence of esophageal cancer from another tumor of unknown primary origin. Endoscopic ultrasound-guided fine-needle aspiration was performed, and the tumor was diagnosed to be neuroendocrine carcinoma. She received concurrent chemoradiotherapy with etoposide plus cisplatin. After the completion of chemoradiotherapy, the tumor disappeared. A solitary growing tumor which develops after radical resection of cancer would be better to be examined histologically in order to make an accurate diagnosis and select the most appropriate treatment.

Mixed adenoneuroendocrine carcinoma (MANEC) of the ampulla of Vater in a Chinese patient: A case report

Mixed adenoneuroendocrine carcinoma (MANEC) is a rare tumour of the gastrointestinal tract with both epithelial and neuroendocrine components. We describe a case of a 57-year-old man who presented with yellow sclera and dark urine. Contrast-enhanced computed tomography (CT) showed enlargement of the intra and extrahepatic bile ducts and a neoplastic lesion at the end of the common bile duct which was indistinguishable from the adjacent head of the pancreas and duodenum. A pancreaticoduodenectomy was performed and histopathological examination of resected samples showed that tumour was a complex lesion with adenocarcinoma and neuroendocrine components positive for neuroendocrine markers (chromogranin A and synaptophysin) with a Ki-67 labelling index of 40%. The patient was diagnosed with MANEC in the ampulla of Vater with a neuroendocrine carcinoma component of approximately 70%. Ampullary MANECs are highly aggressive tumours with a high risk for distant metastases and a poor prognosis. Therefore, establishing a standard therapeutic strategy is crucial.

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.

Efficacy of a third-generation oncolytic herpes simplex virus in neuroendocrine tumor xenograft models

BACKGROUND: Few chemotherapies are available for neuroendocrine tumors, especially for highly malignant neuroendocrine cancers. The third-generation oncolytic herpes simplex virus type 1 (HSV-1) T-01 selectively replicates in tumor cells and shows cytotoxicity against tumor cells without damaging surrounding normal tissues. We examined the antitumor effect of T-01 to explore novel treatments for patients with neuroendocrine tumors.

METHODS: The cytotoxicity of T-01 was tested in two human and one murine neuroendocrine tumor cell lines in vitro. Mouse models with subcutaneously implanted human neuroendocrine tumor QGP1 cells were used to investigate T-01 efficacy in vivo.

RESULTS: T-01 showed cytotoxicity against the three cell lines in vitro. In xenograft models, the growth of tumors derived from QGP1 cells was inhibited by T-01 compared with control group. Although weight loss of mice was observed with tumor growth in the control group, it was suppressed by T-01 administration. The antitumor effects of T-01 were dependent on virus concentration and frequency of administration.

CONCLUSIONS: T-01 effectively inhibits tumor cell proliferation in a poorly differentiated NEC mouse model. These results suggest that the third-generation oncolytic HSV-1 may serve as a novel treatment for patients with neuroendocrine tumors.

Case report of aggressive treatments for large-cell neuroendocrine carcinoma of the esophagus

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Neuroendocrine carcinoma of the esophagus is a rare and highly aggressive disease.

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A case of large-cell neuroendocrine carcinoma of the esophagus in a 73-year-old male patient with aggressive surgical treatment.

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We performed subtotal esophagectomy, partial hepatectomy, radiotherapy and chemotherapy using cisplatin and irinotecan.

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We believe that aggressive treatment can become one treatment option with the aim of extending survival.

Introduction

Neuroendocrine carcinoma of the esophagus is a rare and highly aggressive disease, and the biological features are poorly understood.

Presentation of case

We report a case of large-cell neuroendocrine carcinoma of the esophagus in a 73-year-old male patient with aggressive surgical treatment. Upper gastrointestinal endoscopy revealed an esophageal large mass. Histological examination of biopsy specimens indicated a neuroendocrine carcinoma. First, we performed subtotal esophagectomy with lymphadenectomy, but he experienced metastasis at the liver and rib 5 months later. Next, we performed partial hepatectomy and radiotherapy for rib metastasis, but he experienced metastasis at the left pulmonary hilar lymph node and sacral bone. Finally, we performed chemotherapy using cisplatin and irinotecan.

Discussion

The therapeutic strategy for large-cell NEC of the esophagus is unestablished. Thus, accumulating the therapeutic results garnered from various treatment tools is considerably important.

Conclusion

Aggressive multimodal treatments including surgery have a possibility to gain better survival in patients with large-cell NEC of the esophagus.

Current Treatment Options in Gastroenteropancreatic Neuroendocrine Carcinoma

Poorly differentiated gastroenteropancreatic neuroendocrine carcinomas (GEPNECs) are a rare neoplasm with a bleak prognosis. Currently there are little prospective data available for optimal treatment. This review discusses the current available regimens and the future direction for the treatment of GEPNECs. Treatment plans for GEPNECs are often adapted from those devised for small cell lung cancer; however, differences in these malignancies exist, and GEPNECs require their own treatment paradigms. As such, current first-line treatment for GEPNECs is platinum-based chemotherapy with etoposide. Studies show that response rate and overall survival remain comparable between cisplatin and carboplatin versus etoposide and irinotecan; however, prognosis remains poor, and more efficacious therapy is needed to treat this malignancy. Additional first-line and second-line treatment options beyond platinum-based chemotherapy have also been investigated and may offer further treatment options, but again with suboptimal outcomes. Recent U.S. Food and Drug Administration approval of peptide receptor radionuclide therapy in low- and intermediate-grade neuroendocrine tumors may open the door for further research in its usefulness in GEPNECs. Additionally, the availability of checkpoint inhibitors lends promise to the treatment of GEPNECs. This review highlights the lack of large, prospective studies that focus on the treatment of GEPNECs. There is a need for randomized control trials to elucidate optimal treatment regimens specific to this malignancy. IMPLICATIONS FOR PRACTICE: There are limited data available for the treatment of poorly differentiated gastroenteropancreatic neuroendocrine carcinomas (GEPNECs) because of the rarity of this malignancy. Much of the treatment regimens used in practice today come from research in small cell lung cancer. Given the poor prognosis of GEPNECs, it is necessary to have treatment paradigms specific to this malignancy. The aim of this literature review is to summarize the available first- and second-line GEPNEC therapy, outline future treatments, and highlight the vast gap in the literature.

Establishment of preclinical chemotherapy models for gastroenteropancreatic neuroendocrine carcinoma

Gastroenteropancreatic neuroendocrine carcinoma (GEP-NEC) is a rare and devastating malignancy, and preclinical studies are needed to evaluate potential therapeutic regimens. Here, we examined the antitumor effects of cisplatin (CDDP), etoposide (ETP) and irinotecan (CPT-11) and their combinations on GEP-NEC using three small-cell GEP-NEC cell lines (pancreatic NEC, A99; esophageal NEC, TYUC-1; duodenum NEC, TCC-NECT-2). In vitro studies were conducted using cell viability assays. In vivo experiments were conducted in mice inoculated with A99 or TCC-NECT-2 and treated with no agent, CDDP, CDDP+ETP (EP) or CDDP+CPT-11 (IP). TYUC-1 was the most susceptible to all agents, whereas A99 was refractory. Classical isobolograms showed synergism in both the EP and IP combinations for the three cell lines. In the TCC-NECT-2 mouse model, the IP regimen showed a significant antitumor effect, and CDDP alone showed a marginal effect compared to the control. In contrast, no effect was detected in the A99 model, probably because A99 was established from a metastatic tumor after chemotherapy with EP. Gene expression analysis of the ATP-binding cassette transporters revealed that ATP binding cassette subfamily B member1 (ABCB1) was conspicuously expressed in A99, and ABCB1 and ATP binding cassette subfamily C member2 (ABCC2) were deficient in TYUC-1, which might explain a part of different CDDP susceptibilities between cell lines. These preclinical models indicate that CDDP is a key agent, and IP regimen might be a reasonable option, although its efficacy is moderate. Our data on the platinum-based regimen will be useful as reference information in developing new agents for GEP-NEC.

Management of pulmonary neuroendocrine tumors

Neuroendocrine tumors (NETs) of the lung are divided into 4 major types: small cell lung cancer (SCLC), large cell neuroendocrine carcinoma (LCNEC), atypical carcinoid (AC) or typical carcinoid (TC). Each classification has distinctly different treatment paradigms, making an accurate initial diagnosis essential. The inconsistent clinical presentation of this disease, however, makes this difficult. The objective of this manuscript is to detail the diagnosis and management of the well differentiated pulmonary carcinoid (PC) tumors. A multidisciplinary approach to work up and treatment should be utilized for each patient. A multimodal radiological work-up is used for diagnosis, with contrast enhanced CT predominantly utilized and functional imaging techniques. A definitive diagnosis is based on tissue findings. Surgical management remains the mainstay of therapy and can be curative. In those with advanced disease, medical treatments consist of somatostatin analog (SSA) therapy, targeted therapy, chemotherapy or peptide receptor radionuclide therapy. SSAs are the standard of care in those with metastatic NETs, using either Octreotide long acting repeatable (LAR) or lanreotide as reasonable options, despite a scarcity of prospective data in PCs. Targeted therapies consist of everolimus which is approved for use in PCs, with various studies showing mixed results with other targeted agents. Additionally, radionuclide therapy may be used and has been shown to increase survival and to reduce symptoms in some studies. Prospective trials are needed to determine other strategies that may be beneficial in PCs as well as sequencing of therapy. Successful diagnosis and optimal treatment relies on a multidisciplinary approach in patients with lung NETs. Clinical trials should be used in appropriate patients.

The safety of available treatments options for neuroendocrine tumors

INTRODUCTION

Neuroendocrine neoplasms (NEN) represent a heterogeneous group of malignancies generally characterized by low proliferation and indolent course. However, about half of the newly diagnosed cases are metastatic and require long-term systemic therapies. Areas covered: This review revises the literature to summarize the current knowledge upon safety of all systemic treatment options available. Thirty three different clinical studies have been considered, including 4 on somatostatin analogues (SSA), 5 on targeted therapies, 10 on peptide receptor radionuclide therapy (PRRT), and 14 on chemotherapy. Expert opinion: SSA are safe and well tolerated without any relevant severe adverse event and very low treatment discontinuation rate. Targeted therapies show a satisfying safety profile. Most adverse events are grade 1-2 and easy manageable with dose reduction or temporary interruption. PRRT is manageable and safe with a low rate of grade 3-4 adverse events. However, severe renal and hematologic toxicity may occur. Chemotherapy is usually considered after previous therapeutic lines. Therefore, these subjects are more susceptible to experience adverse events due to cumulative toxicities or poor performance status. The available systemic treatment options are generally well tolerated and suitable for long-term administration. Cumulative toxicity should be taken in account for the definition of therapeutic sequence.

A case of mixed adenoneuroendocrine carcinoma of the pancreas: Immunohistochemical analysis for histogenesis

RATIONALE

Tumors with multiple histological features, such as adenocarcinomas and neuroendocrine carcinomas, were included as a new category of neuroendocrine carcinomas in the 2010 World Health Organization classification. We recently experienced a rare case of a pancreatic carcinoma with both adenocarcinoma and neuroendocrine carcinoma components, a so-called mixed adenoneuroendocrine carcinoma.

PATIENT CONCERNS AND DIAGNOSIS

A 66-year-old man was referred to our hospital with obstructive jaundice. Contrast-enhanced computed tomography images indicated a tumor located at the pancreatic head measuring 3.0 × 2.5 cm in diameter and invading the common bile duct. Cytological examination of the bile juice obtained by endoscopic retrograde cholangiopancreatography revealed adenocarcinoma cells. Pancreaticoduodenectomy was performed safely as radical resection.

INTERVENTIONS

Microscopically, the resected tumor consisted of tightly intermingled adenocarcinoma and neuroendocrine carcinoma components. On the immunohistochemical examination, p53 was ubiquitously positive in both components, whereas chromogranin A, synaptophysin and neuron-specific enolase, neuroendocrine markers, were limited to the neuroendocrine carcinoma component.

OUTCOMES

Thus, such features of both adenocarcinoma and neuroendocrine carcinoma observed microscopically and immunohistochemically seemed to indicate a composite tumor.

LESSONS

The findings of this case suggest that adenocarcinoma and neuroendocrine carcinoma may be derived from a single cancer stem cell.

A mixed adenoneuroendocrine carcinoma of the pancreas: a case report

A tumor consisting of an adenocarcinoma component and a neuroendocrine carcinoma component, with each component accounting for at least 30% of the tumor, is defined as a mixed adenoneuroendocrine carcinoma (MANEC). We report a case of MANEC of the pancreas. A 63-year-old man presented with hyperglycemia and was referred to our hospital for further examination. Abdominal contrast-enhanced computed tomography (CT) revealed a mass of 2 cm in size in the pancreas head with portal vein narrowing. Fluorin-18 fluorodeoxyglucose-positron emission tomography (FDG-PET) CT revealed increased accumulation in the mass of the pancreas head. Endoscopic retrograde cholangiopancreatography (ERCP) showed severe narrowing of the main pancreatic duct. Cytological analysis by endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA) suggested a neuroendocrine tumor. Under the diagnosis of neuroendocrine tumor, pancreaticoduodenectomy with portal vein resection and regional lymph node dissection was performed with curative intent. Histological examination revealed that the tumor consisted of two cell populations. One was well- to moderately differentiated tubular adenocarcinoma. This cell component accounted for 45% of the whole tumor. The second component was non-adenocarcinoma cells arranged in a nest, and the cells had round nuclei, abundant cytoplasm, and coarse chromatin. The Ki67 labeling index was 40%. Immunohistochemically, the adenocarcinoma cells were positive for CEA but negative for chromogranin A (CgA) and synaptophysin (Syn), while the non-adenocarcinoma cells were positive for the expression of CgA and Syn but negative for CEA. Based on the findings, a diagnosis of MANEC of the pancreas was made. Postoperatively, lymph node metastasis and peritoneal dissemination developed rapidly and he died the 6 months after the operation. Due to the small number of reported cases of MANEC of the pancreas, its clinical behavior remains unclear and a standardized management protocol has not been established. Further investigation of more cases of this rare entity is necessary.

Neuroendocrine Tumors

Neuroendocrine tumors are increasingly diagnosed, either incidentally as part of screening processes, or for symptoms, which have commonly been mistaken for other disorders initially. The diagnostic workup to characterize tumor behaviour and prognosis focuses on histologic, anatomic, and functional imaging assessments. Several therapeutic options exist for patients ranging from curative and debulking surgery through to liver-directed therapies and systemic treatments. Multimodal therapies are often required over the patient's disease history. The management paradigm can be complex but should be focused on curative resections and then on controlling symptoms and limiting disease progression. There are several new systemic therapies that have completed phase 3 studies with new compounds being studied in phase 2. Genetic and epigenetic markers may lead to a new era of personalised therapy in the future.

Neuroendocrine tumors of the gastrointestinal tract and the role of cytotoxic chemotherapy

Neuroendocrine tumors (NETs) comprise a heterogeneous group of tumors derived from peptide- and amine-secreting cells of the neuroendocrine system. NETs commonly arise in the gastrointestinal tract but can arise in most organs of the body. Although the incidence of NETs is not high, the prevalence is relatively high because many patients may live relatively long periods without major symptoms from the disease. Whilst many of these tumors take on an indolent clinical course, they constitute a therapeutic challenge when they progress, metastasize and become symptomatic. Treatment requires a multidisciplinary approach that may include cytotoxic chemotherapy. Almost all clinical trials investigating cytotoxic chemotherapy in NETs are small single-arm studies, hence guidelines are derived from expert opinion and from extrapolating results from small-cell lung cancer studies. This article provides a broad coverage of systemic therapies for NETs but focusses on the role of cytotoxic chemotherapy.

Chemotherapy for advanced non-pancreatic well-differentiated neuroendocrine tumours of the gastrointestinal tract, a systematic review and meta-analysis: A lost cause?

BACKGROUND

Chemotherapy is well-established in the treatment of patients with well-differentiated neuroendocrine tumours (NETs) arising from the pancreas (pNETs); however, its role in patients with gastrointestinal non-pancreatic NETs (non-pNETs) is uncertain. This systematic review assesses the evidence for the role of chemotherapy in well-differentiated non-pNET patients.

METHODS

Eligible studies (identified using MEDLINE) were those reporting response and/or survival data for patients with well-differentiated non-pNETs receiving systemic chemotherapy. The primary end-point was overall-response (OR) rate; secondary end-points were progression-free survival (PFS), overall survival (OS), disease-stabilization (DS) and disease-control (DC) rates.

RESULTS

Of 6434 studies screened, 20 were eligible: one randomised phase III trial, 2 randomised phase II studies, 10 single-arm phase II trials and 7 retrospective analyses including a total of 264 patients (median of 11 patients per study, range 6-49); and employing multiple chemotherapy schedules. The mean "median PFS" and "median OS" were 16.9 months (95%-confidence interval (CI) 3.8-30.04) and 32.2 months (95%-CI 10.4-54.2), respectively. The non-weighted mean OR, DS and DC rates were 11.5% (95%-CI 5.8-17.2), 56.5% (95%-CI 38.1-74.9) and 70.7% (95%-CI 54.9-86.5), respectively. In studies including both pNETs and non-pNET patients, meta-analysis showed a lower OR-rate in the non-pNET patients when compared to pNETs [odds ratio (OR) 0.35 (95% CI 0.18-0.66)]; however significance was lost when high-risk bias studies were excluded in a sensitivity analysis [OR 0.45 (95% CI 0.19-1.07); p-value 0.07].

CONCLUSION

Studies were of evidence level-C with heterogeneous populations and treatments; and small patient numbers. Well-designed, prospective studies are needed to adequately evaluate the role of chemotherapy in this setting.

Unusual endoscopic findings of gastric neuroendocrine tumor

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

Amrubicin Monotherapy for Patients with Platinum-Refractory Gastroenteropancreatic Neuroendocrine Carcinoma

Objective. Patients with gastroenteropancreatic neuroendocrine carcinoma (NEC) have a poor prognosis. Platinum-based combination chemotherapy is commonly used as first-line treatment; however, the role of salvage chemotherapy remains unknown. This study aimed to analyze the efficacy and safety of amrubicin monotherapy in patients with platinum-refractory gastroenteropancreatic NEC. Methods. Among 22 patients with advanced gastroenteropancreatic NEC, 10 received amrubicin monotherapy between September 2007 and May 2014 after failure of platinum-based chemotherapy. The efficacy and toxicity of the treatment were analyzed retrospectively. Results. Eight males and two females (median age, 67 years (range, 52–78)) received platinum-based chemotherapy, including cisplatin plus irinotecan (n = 7, 70%), cisplatin plus etoposide (n = 2, 20%), and carboplatin plus etoposide (n = 1, 10%) before amrubicin therapy. Median progression-free survival and overall survival after amrubicin therapy were 2.6 and 5.0 months, respectively. Two patients had partial response (20% response rate), and their PFS were 6.2 months and 6.3 months, respectively. Furthermore, NEC with response for amrubicin had characteristics with a high Ki-67 index and receipt of prior chemotherapy with cisplatin and irinotecan. Grade 3-4 neutropenia and anemia were observed in four and five patients, respectively. Conclusion. Amrubicin monotherapy appears to be potentially active and well-tolerated for platinum-refractory gastroenteropancreatic NEC.

Chemotherapy for advanced poorly differentiated pancreatic neuroendocrine carcinoma

Pancreatic neuroendocrine carcinoma (P-NEC) resembles small cell lung carcinoma in its biologic and clinical features, such as rapid growth and relatively high sensitivity to platinum-based chemotherapy. And, etoposide plus cisplatin (EP) or irinotecan plus cisplatin (IP), recommended by guidelines for the treatment of small cell lung carcinoma, has also been widely used for the treatment of unresectable NEC. Both regimens have been demonstrated to show favorable efficacy and have been acknowledged as de facto standard regimens for unresectable NEC, although it remains unclear which of the two regimens might yield more favorable outcomes. Therefore, a phase III trial of EP vs. IP has been planned for unresectable gastrointestinal, hepatobiliary or pancreatic NEC by the Japan Clinical Oncology Group. For patients with unresectable NEC who are refractory or intolerant to these regimens, no standard regimens have been established. Everolimus, an mTOR inhibitor, is likely to be effective in such patients, as there have been sporadic reports of the usefulness of everolimus in the treatment of P-NEC. A multicenter phase II trial is underway to elucidate the efficacy and safety of everolimus in patients with P-NEC who are refractory or intolerant to EP or IP.

Primary hepatic neuroendocrine carcinoma with a cholangiocellular carcinoma component in one nodule

Primary neuroendocrine carcinomas (NECs) in the liver are very rare; however, several reports have described cases of a primary hepatic NEC combined with a hepatocellular carcinoma (HCC). We present the first report of a primary hepatic NEC with a cholangiocellular carcinoma (CCC) component in one nodule in a patient with a metachronous liver HCC. A 73-year old man who had received partial hepatectomy surgery because of a primary HCC and a primary CCC two years prior was diagnosed with a primary hepatic NEC after surgical treatment. Histological analysis of the resected tumor revealed that the tumor consisted of a predominant NEC area with a partial CCC component in one nodule and that the NEC cells were negative for markers of pancreatic NEC. Neoplastic cells in both the NEC and CCC component focally expressed CD44, a representative marker for cancer-initiating cells, and the CD44-positive cells in the NEC component were seen in the vicinity of those in the CCC component of one nodule. This case report provides suggestive information for the origin of primary hepatic NECs.

Neuroendocrine neoplasms of the GI tract: the role of cytotoxic chemotherapy

Neuroendocrine neoplasms (NENs) comprise a heterogeneous group of neoplasms derived from peptide- and amine-secreting cells of the neuroendocrine system. NENs commonly arise in the GI tract but can arise in most organs of the body. NENs in different organs share many common pathologic features. Although the incidence of NENs is not high, the prevalence is not low because many patients may live relatively long periods without major symptoms from the disease. While many of these tumors lead an indolent clinical course, they constitute a therapeutic challenge when they progress, metastasize and become symptomatic. Treatment requires a multidisciplinary approach including cytotoxic chemotherapy. Almost all clinical trials investigating cytotoxic chemotherapy in NENs are small single-arm studies and guidelines are derived from expert opinion and from extrapolating results from small cell lung cancer studies. This article briefly reviews NENs before focusing on reviewing data on the role of cytotoxic chemotherapy studies in NENs.

Combination of Capecitabine and Oxaliplatin is an Effective Treatment Option for Advanced Neuroendocrine Tumors

The role of chemotherapy in well differentiated neuroendocrine tumors (NET) has been questioned. It was recently demonstrated that everolimus and sunitinib have activity in low and intermediate grade pancreatic NET. The aim of this study was to evaluate the activity of capecitabine and oxaliplatin (CapOx) combination in treating NET in an unselected population. In this regard, we retrospectively evaluated 24 patients diagnosed with metastatic NET treated with CapOx at two Brazilian institutes that are reference centers in cancer care. Tumor response was measured by RECIST criteria. Median age at diagnosis was 56 years, 71% had ECOG 0 or 1, the majority of tumors were primary from pancreas (67%) followed by lung (17%), and 29% were functional. According to WHO classification criteria, 25% were grade 1, 37.5% grade 2 and 37.5% grade 3. Most patients received CapOx as second-line therapy, with a median of 6 cycles. Twenty-nine percent of patients had partial response by RECIST criteria. No association was observed between response rate and tumor grade, primary site or line of CapOx. The median time to progression was 9.8 months and median time to treatment failure was 12.1 months. Seventy-five percent of patients are alive at the time of this analysis; therefore, median overall survival was not reached. The CapOx combination was shown to be active in an unselected population with metastatic NET and may be a good platform for the incorporation of the newer molecular targeted agents being investigated for the treatment of this entity.

Clinicopathologic characteristics of pancreatic neuroendocrine tumors and relation of somatostatin receptor type 2A to outcomes

BACKGROUND

The impact of somatostatin receptor type 2 (SSTR-2a) expression levels on outcomes in patients with pancreatic neuroendocrine tumors (PNETs) has not been evaluated.

METHODS

Correlations between clinicopathologic characteristics, including SSTR-2a expression and outcomes, were retrospectively studied in 79 patients with pancreatic neuroendocrine tumors (PNETs).

RESULTS

The SSTR-2a score was 0 in 27% of patients, 1 in 24% of patients, 3 in 30% of patients, and 4 in 18% of patients. The overall survival rate was 87% at 1 year, 77% at 3 years, and 71% at 5 years. On univariate analysis, a pancreatic tumor that measured ≥ 20 mm in greatest dimension, stage IV disease, vascular invasion, neuroendocrine carcinoma (NEC), and an SSTR-2a score of 0 were associated significantly with poor outcomes. On multivariate analysis, NEC (P = .000; hazard ratio, 28.8; 95% confidence interval, 7.502-111.240) and an SSTR-2a score of 0 (P = .001; hazard ratio, 3.611; 95% confidence interval, 1.344-9.702) were related independently to poor outcomes.

CONCLUSIONS

The current analysis of prognostic factors in patients with PNETs demonstrated that NEC and an SSTR-2a score of 0 both were significant independent predictors of poor outcomes. The results suggest that the assessment of SSTR-2a may facilitate the selection of treatment regimens and the prediction of outcomes. Because a considerable proportion of patients with NEC have SSTR-2a-positive tumors, further analyses of the usefulness of somatostatin analogues are warranted in patients who have SSTR-2a-positive NEC.

Combination of irinotecan and a platinum agent for poorly differentiated neuroendocrine carcinomas

Extrapulmonary poorly differentiated neuroendocrine carcinoma (PDNEC) is a rare and highly aggressive neoplasm for which the optimal chemotherapy remains unclear. The objective of this study was to evaluate the outcomes of patients with PDNEC treated with cisplatin and irinotecan (IP) and perform a review of the literature. From 2008 to 2012, patients with advanced PDNEC (Ki67≥20%) who received the IP combination were selected for analysis. Radiologic responses were determined through Response Evaluation Criteria In Solid Tumors criteria. Twenty-eight patients were included. The median age at diagnosis was 57 years and the most common presentation was pancreatic PDNEC. Twenty-five patients (89%) received chemotherapy with cisplatin and irinotecan and three received carboplatin and irinotecan. Forty-six percent of the patients achieved objective response and the median time to tumor progression was 3.7 months. The median overall survival was 11.7 months. Thirteen patients (46%) had treatment interruptions or dose reductions due to grade 3/4 toxicity. This retrospective cohort of advanced extrapulmonary PDNEC patients suggests that the IP combination is feasible and resulted in similar response rate and median survival to other treatments previously reported.

[Neuroendocrine carcinoma of the digestive tract: a literature review]

Neuroendocrine carcinoma is a rare and agressive malignant tumor, mainly developing at the expense of the respiratory and of the digestive tract. Among the digestive tract, appendix, small bowel, and pancreas are the preferential sites of involvement, other locations have been more rarely reported. Neuroendocrine digestive tumors may present with various symptoms in relationship with their localization and a complex pathophysiology. Diagnosis is often made at an advanced stage, explaining partly the bad prognosis of these tumors. The optimal management of digestive neuroendocrine tumors is rendered difficult by their rarity and by a low number of randomized trials. We review the literature regarding epidemiologic and prognostic features of these rare tumors, their diagnostic and therapeutic care. Potential complications are also discussed.

Systemic therapeutic options for carcinoid

"Carcinoids" are mostly slow-growing neuroendocrine neoplasms (NENs) with low proliferative activity. A wide range of therapeutic options with variable efficacy exist, including locoregional ablative strategies. Thereafter, some patients may not require medical therapy for years depending on the rate of progression or recurrence. However, the majority of patients require systemic treatment and therein lies the dilemma, since no antiproliferative agent is currently approved for carcinoids. Somatostatin analogs (SSAs), and to a lesser extent interferon-alpha, are standard therapy for carcinoids associated with the carcinoid syndrome. These drugs have some antiproliferative efficacy. SSAs rarely lead to tumor remission but may modestly prolong time to tumor progression. Chemotherapy is of limited value in carcinoids with low proliferation indices but may be useful in higher grade tumors. Peptide receptor-targeted radionuclide therapy may be of benefit and is mostly used after medical therapies fail. However, it is considered an investigational modality. More recently, targeted drugs such as mammalian target of rapamycin (mTOR) inhibitors and anti-angiogenics have been investigated. Objective remissions are rare. Their value remains to be rigorously elucidated. Increased efficacy requires a better understanding of the underlying tumor biology and identification of molecular pathological criteria to allow appropriate preselection of candidates for targeted therapies.

Gastric neuroendocrine tumours

BACKGROUND

Gastric neuroendocrine tumours (NETs) are increasingly recognised, and management decisions may be difficult due to an incomplete understanding of aetiology, natural history and optimum therapy. This article presents a current understanding based on recent advances in epidemiology, classification, molecular profiling, and treatment.

METHODS

Relevant medical literature was identified from searches of PubMed and references cited in appropriate articles identified. Selection of articles was based on peer review, journal and relevance.

RESULTS

Gastric NETs may be divided into three clinical prognostic groups: type I is associated with autoimmune atrophic gastritis and hypergastrinaemia, type II is associated with Zollinger-Ellison syndrome, and type III lesions are gastrin-independent, have the greatest metastatic potential and poorest prognosis. There has been an increased frequency of gastric NETs reported. Management approaches have evolved in parallel with advances in endoscopic staging and surgery, as well as improved understanding of the biology and natural history of NETs.

CONCLUSIONS

Gastric NETs present a spectrum of activity from indolent tumours to metastatic malignancy. Treatment decisions for patients must be individualised and are best managed by a multidisciplinary team approach. The current evidence base is limited to small series and efforts to treat patients within clinical networks of expertise are warranted.

CT and enhanced CT in diagnosis of gastrointestinal neuroendocrine carcinomas

OBJECTIVES

To enhance diagnosis of gastrointestinal neuroendocrine carcinomas using CT and contrast-enhanced CT images.

METHODS

A total of 44 patients with gastrointestinal neuroendocrine carcinomas, as confirmed by clinical pathology and immunohistochemistry in the Sixth Affiliated People's Hospital of Shanghai Jiao Tong University Shanghai China, were included in the study. CT and enhanced CT scanning were performed, and the resulting images were reviewed and analyzed.

RESULTS

Twenty-seven males and 17 females were enrolled. Gastrointestinal involvement included the following: 5 cases located in the middle or inferior segment of the esophagus; 5 in the gastric cardia, 15 in the body of stomach, 6 located in the gastric antrum; 5 located in the Vater papilla of the duodenum; and 8 located in the colon. Among the 44 cases 80%-90% of the lesions had homogeneous density. Totally 81.8% (36/44) cases demonstrated homogeneous enhancement in arterial phases, most of the cases (n = 33) moderately or obviously enhanced. Only 17.2% (8/44) cases appeared as heterogeneous enhancement. And 86.4% cases (n = 38) were further enhanced in the venous phase. The CT images also revealed some of the metastases. Some liver metastasis cases have obvious homogeneous enhancement.

CONCLUSIONS

CT and enhanced CT provide useful information regarding gastrointestinal neuroendocrine carcinomas' location, density, enhancement pattern, and some metastasis. These features are helpful to increase the diagnostic accuracy.

Safety and efficacy of everolimus in adult patients with neuroendocrine tumors

Neuroendocrine tumors (NETs) consist of a diverse family of tumors which are derived from the neuroendocrine system. Most NETs are well or moderately differentiated tumors with a relatively indolent growth pattern. However, these tumors can cause significant clinical disease due to release of functional products that mediate the carcinoid syndrome and other diverse sequela. They also can grow progressively and cause symptoms from local invasion or distant metastasis. NETs are optimally treated with surgery and somatosatin analogs (SSA’s) to control symptoms but are relatively insensitive to systemic chemotherapy. As a result, patients with advanced unresectable NETs have a poor prognosis. In 2011, two targeted therapies, sunitinib and everolimus were approved in the subset of progressive pancreatic NETs (pNETs). Everolimus is an oral inhibitor of the growth stimulatory mTOR pathway. In Phase 2 trials in NETs and pNETs, everolimus was well tolerated and associated with some response and widespread disease stabilization. In follow-up, randomized Phase 3 trials, everolimus was compared to placebo. In the RADIANT-2 trial, everolimus and a somatostatin analog were used in patients with functional NETs and treatment was associated with an an improvement in progression-free survival (PFS). In the RADIANT-3 trial, patients with pNET were randomized to receive everolimus or placebo along with best supportive care. Everolimus was again associated with improvement in PFS compared to placebo and it has been approved by the FDA for patients with progressive pNET. Everolimus is associated with frequent low grade toxicity but is also notable for increased rates of infection as well as non-infectious pneumonitis. mTOR inhibition with everolimus represents a significant advance in the treatment of advanced neuroendocrine tumors.

A multimodal approach to the management of neuroendocrine tumour liver metastases

Neuroendocrine tumours (NETs) are often indolent malignancies that commonly present with metastatic disease in the liver. Surgical, locoregional, and systemic treatment modalities are reviewed. A multidisciplinary approach to patient care is suggested to ensure all therapeutic options explored.

Neuroendocrine tumors of the stomach: chemotherapy with cisplatin plus irinotecan is effective for gastric poorly-differentiated neuroendocrine carcinoma

BACKGROUND

Neuroendocrine tumors (NETs) occur in various primary sites, but rarely in the stomach. NETs are classified into three types, carcinoids, malignant carcinoids and poorly differentiated neuroendocrine carcinomas (PNECs), whose clinical behavior is different. Currently, clinical outcomes and standard chemotherapy for NETs of the stomach remain unclear.

METHODS

We conducted a retrospective review of histopathologically confirmed NETs of the stomach at our hospital between January 2000 and August 2006.

RESULTS

Thirty-seven NETs were identified. Fifteen patients had carcinoids while 22 had PNECs. Among the carcinoid patients, 7 underwent endoscopic mucosal resection and 5 had gastrectomy as first-line treatment. Three patients were observed without intervention. All patients were alive after an average follow-up period of 27 months. Among the 22 PNEC patients, 3 had no metastasis, 11 had regional lymph node metastasis, and 8 had distant metastasis. Eight of 14 patients relapsed at a median of 177 days (range 120-1459 days) after curative surgery. Twelve patients with metastatic or recurrent disease received palliative cisplatin plus irinotecan chemotherapy. The response rate was 75%, the median progression-free survival time was 212 days, and median survival time was 679 days.

CONCLUSION

Gastric PNEC patients with distant metastasis had poor outcomes. Regimens containing cisplatin plus irinotecan produced a good response in gastric PNEC.

Clinical effect of temozolomide-based chemotherapy in poorly differentiated endocrine carcinoma after progression on first-line chemotherapy

BACKGROUND

Patients with metastatic poorly differentiated endocrine carcinoma (PDEC) usually have a short survival. The chemotherapy combination of cisplatin and etoposide is frequently used as first-line palliative chemotherapy. There are, however, no published studies concerning second-line treatment of the disease. Temozolomide has shown clinical effect in well-differentiated endocrine carcinomas. This study was performed to evaluate the effect of temozolomide in PDEC patients who had progressed on first-line treatment.

METHODS

Twenty-five patients with PDEC (mainly gastrointestinal) were treated with temozolomide alone or in combination with capecitabine. A subset of patient also received bevacizumab. MGMT methylation was analyzed in tissue specimens. Data were collected retrospectively.

RESULTS

One patient had a complete response, and 7 patients had partial response (33% response rate). Median duration of response was 19 months. Another 9 (38%) patients had a stable disease, after progression at inclusion, with a median duration of 18 months. Median progression-free survival for all patients was 6 months, and median overall survival was 22 months. Only 1 patient had a MGMT methylation.

CONCLUSIONS

Treatment with temozolomide alone or in combination with capecitabine and bevacizumab resulted in objective response or stabilization in 71% of PDEC patients who failed on first-line chemotherapy. These results indicated that temozolomide may be used as second-line treatment in PDEC.

A clinical perspective on gastric neuroendocrine neoplasia

The incidence of gastric neuroendocrine tumors (NETs) has increased exponentially based on widespread use of endoscopy and a greater pathological awareness of the condition. A key concern is the potential association with hypergastrinemia induced by proton pump inhibitor administration. Previous confusion regarding diagnosis and therapy has been diminished by a series of international consensus statements defining the biology and management strategies for the disease. Overall, gastric NETs are categorized as well-differentiated or poorly differentiated neoplasms. Well-differentiated gastric NETs are enterochromaffin-like (ECL) cell tumors subclassified into three types based on their relationship to gastrin, a key regulator of ECL cell neoplastic transformation. The treatment of type 1 and type 2 tumors depends on the size and invasiveness of the tumor, whereas type 3 tumors and poorly differentiated neuroendocrine carcinomas warrant aggressive surgical resection. The disease-specific 5-year survival ranges from about 95% in type 1 gastric carcinoids to about 25% in poorly differentiated gastric NECs. Elucidation of the precise biology of a gastric NET is critical to diagnosis and delineation of a type-specific management strategy.

Well-differentiated neuroendocrine tumors: a review covering basic principles to loco-regional and targeted therapies

Neuroendocrine tumors (NETs) are a complex group of malignancies with variable prognosis and response to treatment. For pancreatic neuroendocrine and carcinoid tumors, traditional cytotoxic chemotherapies have demonstrated minimal activity. Current approaches for treatment of metastatic disease use a combination of loco-regional and targeted biological therapies. Clinical trials remain critical for evaluation of new and promising therapeutic options for patients with NETs.

First-line chemotherapy with capecitabine and temozolomide in patients with metastatic pancreatic endocrine carcinomas

BACKGROUND

Temozolomide is an active agent in metastatic pancreatic endocrine carcinomas. In vitro data indicate that the combination of capecitabine and temozolomide is synergistic for induction of apoptosis in neuroendocrine tumor cell lines. The authors retrospectively evaluated the efficacy of capecitabine and temozolomide in 30 patients with metastatic pancreatic endocrine carcinomas to assess response rate, progression free survival (PFS), and overall survival (OS).

METHODS

Patients with metastatic, well, or moderately differentiated pancreatic endocrine carcinomas who had not received prior systemic chemotherapy were treated with capecitabine (750 mg/m² twice daily, days 1-14) and temozolomide (200 mg/m² once daily, days 10-14) every 28 days.

RESULTS

Among 30 patients treated, 21 (70%) patients achieved an objective radiographic response. Median progression-free survival was 18 months. The rate of survival at two years was 92%. Only 4 patients (12%) experienced grade 3 or 4 adverse events.

CONCLUSIONS

The combination of capecitabine and temozolomide is associated with an exceptionally high and durable response rate in metastatic endocrine carcinomas of the pancreas. Clinical endpoints, including response rate, survival, and toxicity, are superior to those observed with streptozocin-based regimens.

New pharmacologic therapies for gastroenteropancreatic neuroendocrine tumors

Successful treatment of unresectable and metastatic gastroenteropancreatic neuroendocrine tumors (GEP-NETs) requires the thoughtful choice of systemic therapy as a component of a multidisciplinary therapeutic approach. The role of somatostatin analogues is established in symptom relief, but the efficacy of interferon and radiopeptide targeted therapy is not clear. The utility of a variety of tyrosine kinase and antiangiogenic agents is variable and under investigation, whereas the role of cytotoxic chemotherapy in poorly differentiated GEP-NETs is accepted. Overall, the ideal treatment of more indolent tumors is less certain. Reassessments of the GEP-NET pathology classification has provided improved logic for the role of a variety of agents, whereas the precise positioning of many new agents that target molecular pathways of angiogenesis and proliferation is under examination. This article describes the current options for systemic therapy for GEP-NETs within the framework of the current World Health Organization classification system.

Updated Review of the Pathogenesis and Management of Merkel Cell Carcinoma

Background:

Merkel cell carcinoma is a rare, aggressive, malignant cutaneous tumor of the elderly or immunosuppressed individuals that usually appears on sun-exposed areas of the body. Its pathogenesis is still debated, and, currently, no standardized treatment exists.

Objective:

To provide a current updated review of the most relevant data concerning the pathogenesis and management of Merkel cell carcinoma.

Methods:

Using relevant MeSH terms, we performed a review of the literature on these subjects from 1980 to June 2009.

Results and Conclusion:

The current management of Merkel cell carcinoma is based on surgical excision as the majority of patients present with localized disease, whereas up to 30% have regional lymph node metastases. In these cases, the best outcome is achieved with multidisciplinary management that includes radiotherapy. Chemotherapy is part of the treatment in advanced cases and is mandatory for distant metastatis. Given that a recent work showed the presence of a previously unknown polyomavirus, which the authors called Merkel cell polyomavirus, the therapeutical approach to Merkel cell carcinoma could be reconsidered in the future.