Predictive and prognostic factors for treatment and survival in 305 patients with advanced gastrointestinal neuroendocrine carcinoma (WHO G3): the NORDIC NEC study

Streptozocin-Based Chemotherapy in Patients with Advanced Neuroendocrine Neoplasms--Predictive and Prognostic Markers for Treatment Stratification

BACKGROUND AND AIM

Chemotherapy with streptozocin (STZ) in combination with 5-FU or doxorubicin (Dox) represents a standard of care for patients with metastatic pancreatic neuroendocrine neoplasms (pNEN). However, predictive markers for patient selection are still missing. The aim of this study was a retrospective evaluation of the clinicopathological characteristics of pNEN patients receiving STZ-based chemotherapies and to identify predictive and prognostic markers.

PATIENTS AND METHODS

We retrospectively analyzed 77 patients treated at our center between 1995 and 2013. The median overall survival (OS) and progression-free survival (PFS) were calculated using Kaplan-Meier and Cox regression methods, respectively. Uni- and multivariate analyses were performed.

RESULTS

The median PFS (mPFS) in patients receiving STZ/5-FU/Dox was 16 months with a median OS (mOS) of 28 months. Objective response rate (ORR) and disease control rate (DCR) were 34% and 72%, respectively. Biochemical response and positive octreotide scintigraphy predicted objective response. Univariate analysis revealed Ki-67 > 10% and the absence of biochemical or objective response by imaging as independent risk factors for shorter PFS. Additionally, performance status (PS) and resection of the primary tumor were observed to influence mOS. Treatment was well tolerated with less than 10% grade 3 and 4 toxicities.

CONCLUSIONS

STZ-based chemotherapy is an effective and well-tolerated treatment option in patients with well differentiated neuroendocrine neoplasms. Positive octreotide scintigraphy and biochemical response predict objective response.

Pathologic Classification of Neuroendocrine Neoplasms

The pathologic classification of neuroendocrine neoplasms has evolved over the past decades, as new understanding of the biological behavior, histologic characteristics, and genetic features have emerged. Nonetheless, many aspects of the classification systems remain confusing or controversial. Despite these difficulties, much progress has been made in determining the features predicting behavior. Genetic findings have helped establish relationships among different types of neuroendocrine neoplasms and revealed potential therapeutic targets. This review summarizes the current approach to the diagnosis, classification, grading, and therapeutic stratification of neuroendocrine neoplasms, with a focus on those arising in the lung and thymus, pancreas, and intestines.

Systemic Therapies for Advanced Pancreatic Neuroendocrine Tumors

Pancreatic neuroendocrine tumors are an uncommon tumor type and compose 1% to 2% of all pancreatic neoplasms. They are rarely localized at presentation and are typically diagnosed in the presence of metastatic disease. The management poses a significant challenge because of the heterogeneous clinical presentations and varying degrees of aggressiveness. A variety of systemic therapies have been developed for the management of pancreatic neuroendocrine tumors, including somatostatin analogues, a select group of cytotoxic chemotherapy agents, and targeted or biological agents. This article reviews the available systemic therapy options for advanced pancreatic neuroendocrine tumors.

Well-Differentiated Neuroendocrine Tumors with a Morphologically Apparent High-Grade Component: A Pathway Distinct from Poorly Differentiated Neuroendocrine Carcinomas

PURPOSE

Most well-differentiated neuroendocrine tumors (WD-NET) of the enteropancreatic system are low-intermediate grade (G1, G2). Elevated proliferation demonstrated by either a brisk mitotic rate (>20/10 high power fields) or high Ki-67 index (>20%) defines a group of aggressive neoplasms designated as high-grade (G3) neuroendocrine carcinoma (NEC). High-grade NEC is equated with poorly differentiated NEC (PD-NEC) and is associated with a dismal outcome. Progression of WD-NETs to a high-grade neuroendocrine neoplasm very rarely occurs and their clinicopathologic and molecular features need to be characterized.

EXPERIMENTAL DESIGN

We investigated 31 cases of WD-NETs with evidence of a component of a high-grade neoplasm. The primary sites included pancreas, small bowel, bile duct, and rectum. Histopathology of the cases was retrospectively reviewed and selected IHC and gene mutation analyses performed.

RESULTS

The high-grade component occurred either within the primary tumor (48%) or at metastatic sites (52%). The clinical presentation, radiographic features, biomarkers, and the genotype of these WD-NETs with high-grade component remained akin to those of G1-G2 WD-NETs. The median disease-specific survival (DSS) was 55 months (16-119 months), and 2-year and 5-year DSS was 88% and 49%, respectively-significantly better than that of a comparison group of true PD-NEC (DSS 11 months).

CONCLUSIONS

Mixed grades can occur in WD-NETs, which are distinguished from PD-NECs by their unique phenotype, proliferative indices, and the genotype. This phenomenon of mixed grade in WD-NET provides additional evidence to the growing recognition that the current WHO G3 category contains both WD-NETs as well as PD-NECs.

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.

Neuroendocrine tumor G3: a pancreatic well-differentiated neuroendocrine tumor with a high proliferative rate

A 68-year-old man was referred to our hospital because of left upper quadrant pain. Contrast enhanced computed tomography showed a low density mass with delayed contrast effects as well as para-aortic node swelling with homogenous contrast effects. Histological examination of specimens obtained by endoscopic ultrasound fine needle aspiration revealed a pancreatic neuroendocrine tumor (NET) G2, according to the World Health Organization 2010 classification, and lymph node metastasis. Distal pancreatectomy and lymph node dissection were performed. On histological examination, the tumor showed well-differentiated morphology with an organoid pattern. The Ki67 labeling index was 21.6 %, and the mitotic count was 25/10 high power fields. As mentioned above, we made a final diagnosis of the lesion as "NET G3," because the tumor presented with well-differentiated morphology. Chemotherapy with Everolimus was administered. Liver metastasis occurred 11 months after the first operation, and a partial hepatectomy was performed. Histological findings were similar to those of the first operation. Herein we present a case of pancreatic well-differentiated neuroendocrine tumor with a high proliferative rate referred to as "NET G3," and review the relevant literature.

Radiochemotherapy Versus Surgery in Nonmetastatic Anorectal Neuroendocrine Carcinoma: A Multicenter Study by the Association des Gastro-Entérologues Oncologues

Neuroendocrine carcinomas (NEC) of the anus or the rectum are a rare disease, accounting for less than 1% of all digestive malignancies. Most are metastatic at diagnosis and treated with a platinum-based chemotherapy. No guidelines for localized tumors exist. The purpose of this study was to describe the characteristics of anorectal localized NEC, their management and their outcomes.We retrospectively reviewed patients from 11 French centers with anorectal localized NEC. We compared 2 therapeutic managements: surgery (group A) versus chemotherapy with or without radiation (group B). Progression-free survival (PFS) and overall survival (OS) were estimated with the Kaplan-Meier method.A total of 24 patients were identified with a median follow-up of 25 months (3-60 months). Median age was 63 years old and 17 had a rectal tumor (71%). Mean Ki-67 was 72% (range: 20-100), and 75% of the tumors had a high proliferative index (Ki-67 > 50%). Global PFS and OS were 13.1 and 44.1 months, respectively. Thirty-seven percent of patients were in group A and 63% in group B. There was no difference between group A and group B, whether in terms of PFS (13.0 months vs. 13.2 months, P = 0.75) or OS (49.1 months vs. 39.2 months, P = 0.42).In patients with anorectal localized NEC, chemotherapy with or without radiation obtained a similar outcome as surgery and this conservative approach could be deemed a reasonable option.

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.

Long-term outcomes and prognostic factors in 78 Japanese patients with advanced pancreatic neuroendocrine neoplasms: a single-center retrospective study

OBJECTIVE

Despite an increase in the number of Japanese patients with pancreatic neuroendocrine neoplasms, long-term outcomes and prognostic factors, especially for those with advanced disease, remain unclear.

METHODS

We retrospectively reviewed the medical records of 78 patients with unresectable pancreatic neuroendocrine neoplasms treated at our hospital from January 1987 to March 2015. Survival analyses were performed using Kaplan-Meier methods. Prognostic significance of several clinicopathological factors were analyzed by univariate and multivariate analyses using a Cox regression model.

RESULTS

Median overall survivals of pancreatic neuroendocrine tumor (n = 64) and pancreatic neuroendocrine carcinoma (n = 14) were 83.7 and 9.1 months, respectively (hazard ratio: 0.02, 95% confidence interval: 0.01-0.08, P < 0.001). Although no significant differences were observed using a Ki-67 cut-off value of 2% (hazard ratio: 0.46, 95% confidence interval: 0.16-1.13, P = 0.0989), a Ki-67 cut-off of 10% was a significant predictor in patients with pancreatic neuroendocrine tumor (hazard ratio: 9.95, 95% confidence interval, 3.01-32.97, P < 0.001). Treatment after the advent of targeted therapy (hazard ratio: 0.07, 95% confidence interval: 0.03-0.19, P < 0.001) and the presence of bone metastases (hazard ratio: 4.38, 95% confidence interval: 1.42-11.29, P = 0.013) were significant prognostic factors in patients with pancreatic neuroendocrine tumor evaluated by univariate analysis. Multivariate analysis also revealed that a Ki-67 index ≥10% (hazard ratio: 38.8, 95% confidence interval: 8.42-226.62, P < 0.001), approval of targeted therapy (hazard ratio: 0.02, 95% confidence interval: 0.00-0.11, P < 0.001) and bone metastases (hazard ratio: 5.56, 95% confidence interval: 1.10-24.00, P = 0.039) were independent prognostic factors.

CONCLUSIONS

We elucidated the long-term outcomes and prognostic factors in Japanese patients with advanced pancreatic neuroendocrine neoplasms.

The Increasing Relevance of Tumour Histology in Determining Oncological Outcomes in Colorectal Cancer

Colorectal cancer is not just one type of cancer. Differences in outcome and reaction to treatment can at least be partly explained by different histological and molecular subtypes. Recognition of these differences may influence treatment decisions. However, there is huge variation in the amount of information that is available. Several tumour types such as mucinous carcinoma, signet ring cell carcinoma, neuroendocrine carcinoma and adenosquamous carcinoma have such a distinct phenotype that they are readily recognised. However, due to the rarity of signet ring cell carcinoma and adenosquamous carcinoma, limited data are available. More recently defined subtypes, like medullary carcinoma, serrated adenocarcinoma and micropapillary carcinoma, are not adequately diagnosed, which limits research possibilities using large-scale data from registries. In the current review, we systematically describe the histologic subtypes with the clinical and molecular background. We evaluate their prognosis compared to adenocarcinoma not otherwise specified and speculate about the clinical relevance.

Aggressive Locoregional Treatment Improves the Outcome of Liver Metastases from Grade 3 Gastroenteropancreatic Neuroendocrine Tumors

Grade 3 (G3) gastroenteropancreatic (GEP) neuroendocrine tumors (NETs) are rare, and there is no report specifically dealing with patients of liver metastases from G3 GEP NETs.From January 2004 to January 2014, 36 conservative patients with G3 GEP NET liver metastases were retrospectively identified from 3 hepatobiliary centers in China. The clinical features and treatment outcomes were analyzed.Aggressive locoregional treatments (LT, including cytoreductive surgery, radiofrequency ablation, and liver-directed intra-arterial intervention) and systemic therapy (ST) were introduced separately or combined, with 26 (72%) patients receiving resection of primary tumor and/or hepatic metastases, 12 patients receiving non-surgical locoregional interventions (NSLRIs), and 22 patients receiving certain kind of STs. Median overall survival (OS) was 20.0 months (95% confidence interval [CI]: 8.9-31.1 months) and survival rates were 62.6%, 30.1%, and 19.8%, at 1, 3, and 5 years, respectively. The median OS was 9.0 months (95%CI: 3.3-14.7 months) for patients receiving only STs (n = 6), 19 months (95%CI: 1.3-36.8 months) for patients receiving LT followed by STs (n = 16), and 101 months (95%CI: 0.0-210.2 months) for patients receiving only LT (n = 12). Moreover, compared with those receiving only ST or best supportive care, patients given certain types of LTs had higher rates of symptom alleviation (3/8 versus 20/23). On univariate analysis, positive prognostic factors of survival were pancreatic primary tumor (P = 0.013), normal total bilirubin level (P = 0.035), receiving surgery (P = 0.034), receiving NSLRI (P = 0.014), and sum of diameters of remnant tumor < 5 cm (P = 0.008). On multivariate analyses, pancreatic primary tumor (P = 0.015), normal total bilirubin level (P = 0.002), and sum of diameters of remnant tumor < 5 cm (P = 0.001) remained to be independent prognostic factors.For patients with G3 GEP NET liver metastases, aggressive LTs may improve clinical outcomes. Larger studies with prospective design are warranted to consolidate these results, and to discover the most appropriate seletion criteria for patients to undergo different kinds of aggressive LTs and to find the most effective combinations, with or without ST.

Characteristics and treatment of patients with G3 gastroenteropancreatic neuroendocrine neoplasms

Data on gastroenteropancreatic neuroendocrine neoplasms (NEN) G3 (well-differentiated neuroendocrine tumors (NET G3) and neuroendocrine carcinoma (NEC)) are limited. We retrospectively study patients with NET G3 and NEC from eight European centers. Data examined included clinical and pathological characteristics at diagnosis, therapies and outcomes. Two hundred and four patients were analyzed (37 NET G3 and 167 NEC). Median age was 64 (21-89) years. Tumor origin included pancreas (32%) and colon-rectum (27%). The primary tumor was resected in 82 (40%) patients. Metastatic disease was evident at diagnosis in 88% (liver metastases: 67%). Median Ki-67 index was 70% (30% in NET G3 and 80% in NEC; P<0.001). Median overall survival (OS) for all patients was 23 (95% CI: 18-28) months and significantly higher in NET G3 (99 vs 17 months in NEC; HR=8.3; P<0.001). Platinum-etoposide first line chemotherapy was administered in 113 (68%) NEC and 12 (32%) NET G3 patients. Disease control rate and progression free survival (PFS) were significantly higher in NEC compared to NET G3 (P<0.05), whereas OS was significantly longer in NET G3 (P=0.003). Second- and third-line therapies (mainly FOLFIRI and FOLFOX) were given in 79 and 39 of NEC patients; median PFS and OS were 3.0 and 7.6 months respectively after second-line and 2.5 and 6.2 months after third-line chemotherapy. In conclusion, NET G3 and NEC are characterized by significant differences in Ki-67 index and outcomes. While platinum-based chemotherapy is effective in NEC, it seems to have limited value in NET G3.

Efficacy of endoscopic ultrasonography-guided fine needle aspiration for pancreatic neuroendocrine tumor grading

AIM: To evaluate the efficacy of endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA) for grading pancreatic neuroendocrine tumors (PNETs).

METHODS: A total of 22 patients were diagnosed with PNET by EUS-FNA between October 2001 and December 2013 at Fukushima Medical University Hospital. Among these cases, we targeted 10 PNET patients who were evaluated according to the World Health Organization (WHO) 2010 classification. Surgery was performed in eight patients, and chemotherapy was performed in two patients due to multiple liver metastases．Specimens obtained by EUS-FNA were first stained with hematoxylin and eosin and then stained with chromogranin, synaptophysin, CD56, and Ki-67. The specimens were graded by the Ki-67 index according to the WHO 2010 classification. Specimens obtained by surgery were graded by the Ki-67 index and mitotic count (WHO 2010 classification). For the eight specimens obtained by EUS-FNA, the Ki-67 index results were compared with those obtained by surgery. In the two cases treated with chemotherapy, the effects and prognoses were evaluated.

RESULTS: The sampling rate for histological diagnosis by EUS-FNA was 100%. No adverse effects were observed. The concordance rate between specimens obtained by EUS-FNA and surgery was 87.5% (7/8). For the two cases treated with chemotherapy, case 1 received somatostatin analog therapy and transcatheter arterial infusion (TAI) targeting multiple liver metastases. Subsequent treatment consisted of everolimus. During chemotherapy, the primary tumor remained unconfirmed, although the multiple liver metastases diminished dramatically. Case 2 was classified as neuroendocrine carcinoma (NEC) according to the Ki-67 index of a specimen obtained by EUS-FNA; therefore, cisplatin and irinotecan therapy was started. However, severe adverse effects, including renal failure and diarrhea, were observed, and the therapy regimen was changed to cisplatin and etoposide. TAI targeting multiple liver metastases was performed. Although the liver metastases diminished, the primary tumor remained unconfirmed. These chemotherapy regimens had immediate effects for both unresectable neuroendocrine tumor (NET) and NEC cases. These two subjects are still alive.

CONCLUSION: EUS-FNA was effective for PNET diagnosis and Ki-67 index grading for WHO 2010 classification, enabling informed decisions on unresectable PNET treatment by identifying NET or NEC.

Evolution in the treatment of gastroenteropancreatic-neuroendocrine neoplasms, focus on systemic therapeutic options: a systematic review

ABSTRACT 

Neuroendocrine neoplasms (NENs) are a group of heterogeneous tumors. The present review discusses current therapeutic strategies for the treatment of gastro-entero-pancreatic NEN. Several systemic options are currently available, including medical systemic chemotherapy, biological drugs, somatostatin analogs and peptide receptor radionuclide therapy. The carcinoid syndrome can be adequately controlled with somatostatin analogs; chemotherapy has shown positive outcomes in poor prognosis patients, and peptide receptor radionuclide therapy is a promising treatment based on the use of radioisotopes for advanced disease expressing somatostatin receptors. Targeted therapies, such as multikinase inhibitors and monoclonal antibodies are also recommended or under evaluation for the treatment of advanced NENs, but some critical issues in clinical practice remain unresolved. Depending upon the development of the disease, a multimodal approach is recommended. The treatment strategy for metastatic patients should be planned by a multidisciplinary team in order to define the optimal sequence of treatments.

The high-grade (WHO G3) pancreatic neuroendocrine tumor category is morphologically and biologically heterogenous and includes both well differentiated and poorly differentiated neoplasms

The 2010 World Health Organization (WHO) classification recommends that pancreatic neuroendocrine tumors (PanNETs) be graded on the basis of the mitotic rate and Ki67 index, with grade 2 (G2) PanNETs defined as having a mitotic rate of 2 to 20 mitotic figures/10 high-power fields or a Ki67 index of 3% to 20%. Grade 3 (G3) pancreatic neuroendocrine carcinoma (NEC) is defined as having >20 mitotic figures/10 high-power fields or a Ki67 index of >20%. However, some PanNETs show discordance between the mitotic rate and Ki67 index, usually having a Ki67 index in the G3 range but a mitotic rate suggesting G2, prompting us to examine the clinical significance of the Ki67 index in a large series of clinically well-characterized mitotic G2 PanNETs. Mitotic G2 well differentiated PanNETs, surgically resected at our institutions were reviewed. Of those, 19 cases had a Ki67>20% and were selected as the study group of grade-discordant (mitotic count G2/Ki67 index G3) PanNETs. For comparison, 53 grade-concordant (both mitotic count and Ki67 index G2) PanNETs matched for presenting stage with the discordant group as well as 43 morphologically poorly differentiated (either small cell or large cell type) pancreatic NECs were also included. The percentage of Ki67-positive neoplastic cells was quantified by manual counting of at least 500 cells on printed photographic images of "hot spots." The mean Ki67 index for grade-concordant and grade-discordant PanNETs and poorly differentiated NECs were 8.1% (range, 3% to 20%), 40% (range, 24% to 80%), and 70% (range, 40% to 98%), respectively. Overall, patients with grade-discordant PanNETs had significantly longer survival time compared with the patients with poorly differentiated NEC (median survival of 54.1 vs. 11 mo and 5 y survival of 29.1% vs. 16.1%; P=0.002). In addition, the survival time of the patients with grade-discordant PanNETs was shorter than that of the patients with grade-concordant PanNETs (median survival of 67.8 mo and 5 y survival of 62.4%); however, the difference was not statistically significant (P=0.2). Our data support the notion that the mitotic rate and Ki67 index-based grades of PanNETs can be discordant, and when the Ki67 index indicates G3, the clinical outcome is slightly worse. More importantly, we demonstrate that well differentiated PanNETs that are G3 by Ki67 are significantly less aggressive than bona fide poorly differentiated NECs, suggesting that the current WHO G3 category is heterogenous, contains 2 distinct neoplasms, and can be further separated into well differentiated PanNET with an elevated proliferation rate and poorly differentiated NEC.

Carcinoid and neuroendocrine tumors: building on success

We have come a long way in our understanding and treatment of neuroendocrine tumors since the term "karzinoide" was coined in 1907. Neuroendocrine tumors are a group of biologically and clinically heterogeneous neoplasms that most commonly originate in the lungs, GI tract, and pancreas. The selection of initial and subsequent therapies requires careful consideration of both tumor and treatment characteristics. With recent advances, we now have more tools for the diagnosis and treatment of our patients. This comprehensive review article summarizes recent advances in the field of neuroendocrine tumors and places them into context for best management practices.

Neuroendocrine Carcinomas of the Gastroenteropancreatic System: A Comprehensive Review

To date, empirical literature has generally been considered lacking in relation to neuroendocrine carcinomas (NECs), the highly malignant subgroup of neuroendocrine neoplasms. NECs are often found in the lungs or the gastroenteropancreatic (GEP) system and can be of small or large cell type. Concentrating on GEP-NECs, we can conclude that survival times are poor, with a median of only 4–16 months depending on disease stage and primary site. Further, this aggressive disease appears to be on the rise, with incidence numbers increasing while survival times are stagnant. Treatment strategies concerning surgery are often undecided and second-line chemotherapy is not yet established. After an analysis of over 2600 articles, we can conclude that there is indeed more empirical literature concerning GEP-NECs available than previously assumed. This unique review is based on 333 selected articles and contains detailed information concerning all aspects of GEP-NECs. Namely, the classification, histology, genetic abnormalities, epidemiology, origin, biochemistry, imaging, treatment and survival of GEP-NECs are described. Also, organ-specific summaries with more detail in relation to disease presentation, diagnosis, treatment and survival are presented. Finally, key points are discussed with directions for future research priorities.

The p53 network as therapeutic target in gastroenteropancreatic neuroendocrine neoplasms

Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) are heterogeneous and especially the midgut tumors currently lack effective therapy options. Actionable driver mutations as therapeutic targets are rare. Subtype specific data concerning regulatory mechanisms or epigenetic aberrations are necessary for novel clinical trials. Although the p53 protein itself is rarely mutated in GEP-NENs, epigenetic and regulatory aberrations interfere with the p53 network activity and might function as s target for novel therapeutic approaches. In this review we analyze the current knowledge about the p53 network in GEP-NENs and discuss three possible strategies that include recovering p53 function, enforcing apoptosis by genotoxic stress induction and restoring silenced gene function, based on in vitro, in vivo and clinical data.

A retrospective review of diagnosis and treatment modalities of neuroendocrine tumors (excluding primary lung cancer) in 10 oncological institutions of the East German Study Group of Hematology and Oncology (OSHO), 2010-2012

RATIONALE

There is a paucity of data on the incidence of neuroendocrine tumors (NET) outside pulmonary primaries and on treatment modalities applied to patients with NET in clinical practice. Only very little therapeutic progress has been made with respect to response and overall survival, particularly among patients with poorly differentiated, WHO grade 3 neuroendocrine carcinomas (G3-NEC). We sought to document the incidence and treatment modalities in patients with NET/NEC within a period of 2 years.

METHODS

We conducted a retrospective data analysis using a simple documentation file to be completed in written form or electronically, including localization, WHO grading, treatment modalities, and specific therapeutic regimens applied. Primary lung cancer was excluded. The time period to be covered was 2010 through 2012. Individual patient data such as names or age were not documented, so that no ethics committee approval was required.

RESULTS

Ten different hospital- or practice-based institutions contributed their data. One to 35 patients were documented per institution, summing up to 149 patients with 154 tumor localizations. Midgut (n = 46), foregut (n = 42), hindgut (n = 17), lung (n = 9), bladder (n = 8), unknown primary (n = 11), and other including prostate and liver (n = 21) were documented as tumor sites. Histological gradings were G1 (n = 71), G2 (n = 27), G3 (n = 34), undifferentiated "G4" (n = 4), and not specified (n = 13). Treatment modalities were surgical resection (n = 102), chemotherapy (n = 49), somatostatin analogs (n = 39), radiotherapy (n = 22), receptor-directed radionuclide therapy (n = 12), and systemic tyrosine kinase inhibition (n = 5). Chemotherapy was given to patients not only with G3-NEC (n = 31), but also with G2 (n = 12) and G1 NET (n = 7). Somatostatin analogs as well as receptor-directed radionuclides were applied to patients throughout all gradings.

CONCLUSIONS

NET and NEC are not very rare tumor entities, but are diagnosed with very different frequencies, possibly depending upon the alertness of pathologists and clinicians. Chemotherapy, receptor-directed radionuclide application, and somatostatin analog therapy are applied without a clear correlation to different histologic gradings. Diagnostic and therapeutic progress in the field of NETs/carcinomas is urgently needed.

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.

Survival of patients with neuroendocrine carcinoma of the colon and rectum: a population-based analysis

BACKGROUND

High-grade neuroendocrine carcinoma is a rare colorectal pathology described in a case series. The role of surgery in this disease has been questioned.

OBJECTIVE

The purpose of this work was to describe the incidence, management, and outcomes of neuroendocrine carcinoma in comparison with high-grade adenocarcinoma.

DESIGN

This was a retrospective, population-based outcomes research study.

SETTINGS

The Survey of Epidemiology and End Results database was used.

PATIENTS

A total of 1367 patients with colorectal neuroendocrine carcinoma (distinguishing small-cell and non-small-cell subtypes) and 72,533 with high-grade adenocarcinoma diagnosed between 2000 and 2011 were included in this study.

INTERVENTIONS

Resection of the primary tumor was the main intervention.

MAIN OUTCOME MEASURES

Median overall and 5-year relative survival were measured. Trends were expressed as the annual percent change in incidence and relative survival.

RESULTS

The incidence rate increased for neuroendocrine carcinoma (annual percent change, +2.2%; p =0.035) and decreased for high-grade adenocarcinoma (annual percent change, -3.1%; p < 0.00001) during the study period. Relative survival at 5 years in neuroendocrine carcinoma was 16.3% overall and 57.4%, 56.4%, 26.3%, and 3.0% for stages I, II, III, and IV cancer. Small-cell tumors had worse survival (10% versus 19% for non-small cell). There was no improvement in the relative survival for neuroendocrine carcinoma (annual percent change, -1.1%; p =0.06) in contrast to adenocarcinoma (annual percent change, +0.7%; p < 0.00001). Patients with localized non-small-cell neuroendocrine carcinoma had better overall survival with surgery (median, 21 months) than without (6 months; log-rank, p < 0.0001), whereas those with small-cell neuroendocrine carcinoma did not (18 versus 14 months; p = 0.95). Prognosis in resected neuroendocrine carcinoma was worse with an increasing number of metastatic lymph nodes.

LIMITATIONS

Histology and grade assignments were not centrally verified. Data on chemotherapy use, patient performance status, and comorbidities were unavailable.

CONCLUSIONS

Neuroendocrine carcinoma did not benefit from advances in the prevention and treatment of colorectal adenocarcinoma over the past decade. Relatively poor survival in early stage neuroendocrine carcinoma warrants studies of adjuvant systemic therapy. The differences in outcomes between small-cell and non-small-cell neuroendocrine carcinomas indicate a need for histology-specific management.

Beyond biologics: is there a role for systemic cytotoxic chemotherapy in neuroendocrine tumors?

Abstract: 

Neuroendocrine tumors (NETs) are a group of biologically and clinically heterogeneous neoplasms that have varying degrees of responsiveness to systemic and targeted therapies. With recent advances in therapeutics, a number of biologic therapies have been incorporated into the management of NETs. In this review, we discuss the role of cytotoxic chemotherapy in the management of NETs with an overview of past and present clinical trials, current treatment guidelines and future directions.

Mitotic count by phosphohistone H3 immunohistochemical staining predicts survival and improves interobserver reproducibility in well-differentiated neuroendocrine tumors of the pancreas

Well-differentiated neuroendocrine tumors (WDNETs) of the pancreas are graded on the basis of mitotic count or Ki67 index. Mitotic count has a narrow cutoff; its assessment is time consuming and carries poor interobserver reproducibility. Phosphohistone H3 (PHH3) is a mitosis-specific marker whose value has been validated in several tumor types. We sought to assess the utility of PHH3 in histologic grading of pancreatic WDNETs. Sixty-three cases of surgically resected primary pancreatic WDNETs were retrieved, and immunohistochemical analysis for PHH3 and Ki67 was performed. Mitotic rate was independently assessed by 4 pathologists on hematoxylin and eosin (HE; in 50 high-power fields [HPFs], expressed as mitoses/10 HPF) and PHH3 stains (in 50 HPFs, one 10×, and one 20× hotspot). PHH3 and Ki67 labeling indices were determined on a single 20× hotspot and expressed as the percentage of positive cells to total cells. We found that mitotic counts by various methods significantly correlated with each other and also with PHH3 and Ki67 indices, with the best correlation seen within the 3 different PHH3 counts (in 50 HPFs, one 10× and one 20× hotspot). Moreover, mitotic count on PHH3 was less time consuming than that on HE (1.68 vs. 3.67 min for 50 HPFs, P<0.0001). Histologic grade determined by PHH3 significantly correlated with disease-specific and disease-free survivals, with the best cutoffs of ≥4 mitoses/10 HPF (2 mm), ≥7 mitoses/10× hotspot, ≥5 mitoses/20× hotspot (log rank test, P<0.0001), and ≥0.16% for PHH3 labeling index (log rank test, P<0.0006). Tumor grades based on PHH3 stain also showed significant correlation with patient survivals in multivariate Cox proportional hazards models (P<0.05). Histologic grades by mitotic counts on PHH3 demonstrated high concordance and κ agreement with grades determined by mitotic count on HE. PHH3 stain also showed improved interobserver agreement in both original mitotic count (intraclass correlation 0.98 vs. 0.79) and final grade assignment (Fleiss κ 0.69 vs. 0.46) as compared with HE. Thus, our data confirmed that histologic grading by PHH3 stain has practical and prognostic values and offers reduced time and improved interobserver reproducibility in mitotic rate assessment and grade assignment. Although larger series are needed for validation, mitotic rate can potentially be determined by counting 1 hotspot, which will greatly facilitate the assessment of histologic grade in pancreatic WDNETs.

Microsatellite unstable gastrointestinal neuroendocrine carcinomas: a new clinicopathologic entity

Gastroenteropancreatic (GEP) neuroendocrine carcinomas (NECs) and mixed adenoneuroendocrine carcinomas (MANECs) are heterogeneous neoplasms characterized by poor outcome. Microsatellite instability (MSI) has recently been found in colorectal NECs showing a better prognosis than expected. However, the frequency of MSI in a large series of GEP-NEC/MANECs is still unknown. In this work, we investigated the incidence of MSI in GEP-NEC/MANECs and characterized their clinicopathologic and molecular features. MSI analysis and immunohistochemistry for mismatch repair proteins (MLH1, MSH2, MSH6 and PMS2) were performed in 89 GEP-NEC/MANECs (six esophageal, 77 gastrointestinal, three pancreatic, and three of the gallbladder). Methylation of 34 genes was studied by methylation-specific multiplex ligation probe amplification. Mutation analysis of BRAF and KRAS was assessed by PCR-pyrosequencing analysis. MSI was observed in 11 NEC/MANECs (12.4%): seven intestinal and four gastric. All but two MSI-cases showed MLH1 methylation and loss of MLH1 protein. The remaining two MSI-cancers showed lack of MSH2 or PMS2 immunohistochemical expression. MSI-NEC/MANECs showed higher methylation levels than microsatellite stable NEC/MANECs (40.6% vs 20.2% methylated genes respectively, P<0.001). BRAF mutation was detected in six out of 88 cases (7%) and KRAS mutation was identified in 15 cases (17%). BRAF mutation was associated with MSI (P<0.0008), while KRAS status did not correlate with any clinicopathologic or molecular feature. Vascular invasion (P=0.0003) and MSI (P=0.0084) were identified as the only independent prognostic factors in multivariate analysis. We conclude that MSI identifies a subset of gastric and intestinal NEC/MANECs with distinct biology and better prognosis. MSI-NEC/MANECs resemble MSI-gastrointestinal adenocarcinomas for frequency, molecular profile and pathogenetic mechanisms.

Multiple, persistent gastropancreato-neuroendocrine tumours accompanying sigmoid bowel adenocarcinoma: A rare case report

Introduction

Gastropancreato-neuroendocrine tumours (GETs) are rare, especially when they occur alongside colorectal adenocarcinoma. Furthermore, multiple GETs occurring within the small bowel are less frequent with only two cases described within the literature.

Presentation of case

A healthy 58-year old woman presented with severe gastrointestinal pain and faecal incontinence. Family history revealed consanguineous parents and a brother who had recently died of a gastric GET. First biopsy showed a sigmoid adenocarcinoma. Histology of the resected sigmoid revealed both adenocarcinoma and GET. After this, she presented with small bowel obstruction secondary to multiple ileal and jejunal GETs, also treated with resection. All imaging modalities gave no evidence of extra-intestinal metastasis. The patient received multiple operations and chemotherapy but died 18 months after the original presentation.

Discussion

A case of such persistent and multiple small bowel GET without extra-intestinal metastasis has yet to be reported within the literature. GETs are rare and typically asymptomatic with a small proportion giving the classical carcinoid syndrome. Surgery is usually reserved for smaller GETs with high five-year survival. Despite this, surgery and chemotherapy were performed and both proved to be ineffective. Furthermore, a genetic basis for GETs is supported in this case with her brother suffering a similar fatal tumour.

Conclusion

This case highlights a rare GET that has a likely underlying familial origin. It illustrates the non-specific presentation of these tumours and the importance of taking a thorough family history. It also demonstrates that these tumours can be fatal even in the absence of extra-intestinal metastasis.

Genetics of pancreatic neuroendocrine tumors: implications for the clinic

Pancreatic neuroendocrine tumors (PanNETs) are a common and deadly neoplasm of the pancreas. Although the importance of genetic alterations in PanNETs has been known for many years, recent comprehensive sequencing studies have greatly expanded our knowledge of neuroendocrine tumorigenesis in the pancreas. These studies have identified specific cellular processes that are altered in PanNETs, highlighted alterations with prognostic implications, and pointed to pathways for targeted therapies. In this review, we will discuss the genetic alterations that play a key role in PanNET tumorigenesis, with a specific focus on those alterations with the potential to change the way patients with these neoplasms are diagnosed and treated.

Long-Term Outcomes of Surgical Management of Pancreatic Neuroendocrine Tumors with Synchronous Liver Metastases

BACKGROUND

The value of surgical resection in the management of pancreatic neuroendocrine tumors (PNET) with liver metastases (LM) is still debated. The aim of this study was to evaluate the outcomes of surgery of PNET with LM.

METHODS

Patients with PNET with synchronous LM between 2000 and 2011 from 4 high-volume institutions were included. The patients were divided into 3 groups: curative resection, palliative resection, and no resection.

RESULTS

Overall, 166 patients were included. Eighteen patients (11%) underwent curative resection, 73 patients (43%) underwent palliative resection, and 75 patients (46%) underwent conservative treatment. The median overall survival (OS) from the time of diagnosis was 73 months. Patients who underwent curative resection had a significantly better median OS from the initial diagnosis compared with those who underwent palliative resection and those who were conservatively treated (97 vs. 89 vs. 36 months, p = 0.0001). The median OS from the time of diagnosis in those patients who underwent radical or palliative resection was 97 months, with a 5-year survival rate of 76%. On multivariate analysis, factors associated with OS from the time of diagnosis were the presence of bilobar metastases, tumor grading, and curative resection in a first model. On a second model, curative or palliative surgery was an independent predictor of OS. Among 91 patients who underwent surgery, the presence of pancreatic neuroendocrine carcinoma G3 was the only factor independently associated with a poorer survival after surgery (median OS: 35 vs. 97 months, p < 0.0001).

CONCLUSIONS

Patients with LM from PNET benefit from surgical resection, although surgery should be reserved to well- or moderately differentiated forms.

Does the WHO 2010 classification of pancreatic neuroendocrine neoplasms accurately characterize pancreatic neuroendocrine carcinomas?

BACKGROUND

The WHO classified pancreatic neuroendocrine neoplasms in 2010 as G1, G2, and neuroendocrine carcinoma (NEC), according to the Ki67 labeling index (LI). However, the clinical behavior of NEC is still not fully studied. We aimed to clarify the clinicopathological and molecular characteristics of NECs.

METHODS

We retrospectively evaluated the clinicopathological characteristics, KRAS mutation status, treatment response, and the overall survival of eleven pNEC patients diagnosed between 2001 and 2014 according to the WHO 2010. We subclassified WHO-NECs into well-differentiated NEC (WDNEC) and poorly differentiated NEC (PDNEC). The latter was further subdivided into large-cell and small-cell subtypes.

RESULTS

The median Ki67 LI was 69.1% (range 40-95%). Eleven WHO-NECs were subclassified into 4 WDNECs and 7 PDNECs. The latter was further separated into 3 large-cell and 4 small-cell subtypes. Comparisons of WDNEC vs. PDNEC revealed the following traits: hypervascularity on CT, 50% (2/4) vs. 0% (0/7) (P = 0.109); median Ki67 LI, 46.3% (40-53%) vs. 85% (54-95%) (P = 0.001); Rb immunopositivity, 100% (4/4) vs. 14% (1/7) (P = 0.015); KRAS mutations, 0% (0/4) vs. 86% (6/7) (P = 0.015); response rates to platinum-based chemotherapy, 0% (0/2) vs. 100% (4/4) (P = 0.067), and median survival, 227 vs. 186 days (P = 0.227).

CONCLUSIONS

The WHO-NEC category may be composed of heterogeneous disease entities, namely WDNEC and PDNEC. These subgroups tended to exhibit differing profiles of Ki67 LI, Rb immunopositivity and KRAS mutation, and distinct response to chemotherapy. Further studies for the reevaluation of the current WHO 2010 classification are warranted.

Roles of the pathologist in evaluating surrogate markers for medical therapy in adrenocortical carcinoma

Adrenocortical carcinoma is a rare malignancy. Medical treatment including op'DDD or mitotane with or without platinum-based cytotoxic chemotherapy is frequently administered to the patients in an adjuvant setting following surgery or in advanced disease, because of aggressive clinical behavior in some cases. Potential roles of pathologists in determining the clinical algorithm of medical therapy are histopathological confirmation of adrenocortical carcinoma, both malignant features using the criteria of Weiss and adrenocortical origin applying immunohistochemistry of steroid factor-1 (SF-1); providing the relevant pathological information to determine the precise pathological stage in individual patients; and providing the accurate Ki67 labeling index of the patients. There are no established pathological surrogate markers for response to mitotane or op' DDD therapy available at this juncture but as in other malignancies, Ki67 LI could provide information as to the potential clinical response to platinum-based cytotoxic chemotherapy. Epidermal growth factor receptor (EGFR) is significantly overexpressed in adrenocortical carcinoma but the absence of gene mutations could limit the therapeutic application of anti-EGFR antibody and/or EGFR tyrosine kinase inhibitor in the patients.

A tale of two tumors: treating pancreatic and extrapancreatic neuroendocrine tumors

Despite their perceived rarity, gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are rising in incidence and prevalence. The biology, natural history, and therapeutic options for GEP-NETs are heterogeneous: NETs arising in the pancreas can be distinguished from those arising elsewhere in the gastrointestinal tract, and therapy is dichotomized between these two groups. Somatostatin analogues are the mainstay of oncologic management of bowel NETs; everolimus, streptozocin, and sunitinib are approved to treat pancreatic NETs. There are significant differences in molecular genetics between pancreatic and extrapancreatic NETs, and studies are evaluating whether additional NET patients may benefit from targeted agents. We discuss the distinguishing features of these two groups of tumors, as well as the therapeutic implications of the distinction. We also examine the evolving therapeutic landscape and discuss the likelihood that treatment will be developed independently for pancreatic and extrapancreatic gastrointestinal NETs, with novel therapeutics effective for newly identified pathologically or molecularly defined subgroups.

Nordic guidelines 2014 for diagnosis and treatment of gastroenteropancreatic neuroendocrine neoplasms

BACKGROUND

The diagnostic work-up and treatment of patients with neuroendocrine neoplasms (NENs) has undergone major recent advances and new methods are currently introduced into the clinic. An update of the WHO classification has resulted in a new nomenclature dividing NENs into neuroendocrine tumours (NETs) including G1 (Ki67 index ≤ 2%) and G2 (Ki67 index 3-20%) tumours and neuroendocrine carcinomas (NECs) with Ki67 index > 20%, G3. Aim. These Nordic guidelines summarise the Nordic Neuroendocrine Tumour Group's current view on how to diagnose and treat NEN-patients and are meant to be useful in the daily practice for clinicians handling these patients.

Pancreatic neuroendocrine tumors: pathologic and molecular characteristics

Pancreatic neuroendocrine neoplasms include mainly well-differentiated neuroendocrine tumors but also rare poorly differentiated neuroendocrine carcinomas. Molecular mechanisms underlying pancreatic neuroendocrine tumorigenesis have recently been elucidated. While alterations in the chromatin remodeling and PI3K/Akt/mTOR pathways are present in most well-differentiated pancreatic neuroendocrine tumors, mutations in TP53 and RB may contribute to the development of pancreatic poorly differentiated neuroendocrine carcinomas. With these discoveries, new molecular targeted therapies have become available and show promise in some patients with pancreatic well-differentiated neuroendocrine tumor.

Favourable outcomes of (177)Lu-octreotate peptide receptor chemoradionuclide therapy in patients with FDG-avid neuroendocrine tumours

PURPOSE

Increased glycolytic activity on FDG PET/CT defines a subgroup of patients with metastatic gastroenteropancreatic neuroendocrine tumour (NET) with a poor prognosis. A limited range of systemic treatment options exist for more aggressive NET. The role of peptide receptor chemoradionuclide therapy (PRCRT) in such patients is, however, unclear. This retrospective study assessed the outcomes of patients with FDG-avid NET treated with PRCRT.

METHODS

Clinical, biochemical and imaging response was assessed after completion of induction treatment of PRCRT with 5-fluorouracil in 52 patients selected for treatment on the basis of somatostatin-receptor imaging without spatially discordant FDG-avid disease. Of the cohort, 67% had received prior chemotherapy. Overall survival (OS) and progression-free survival (PFS) were also analysed.

RESULTS

PRCRT was well tolerated with negligible grade 3/4 toxicities. After a median follow-up period of 36 months, the median OS was not achieved with a median PFS of 48 months. At 3 months after completion of PRCRT 2% of patients showed a complete anatomical response, 28% a partial response, 68% stable disease, and only 2% progression. On FDG PET/CT, 27% achieved a complete metabolic response during the follow-up period. A biochemical response (>25% fall in chromogranin-A levels) was seen in 45%.

CONCLUSION

PRCRT is an effective treatment in patients with FDG-avid NET, even in patients who have failed conventional therapies. Given apparently higher response rates than with alternative therapeutic options and low toxicity, further research is needed to establish whether PRCRT should be used as a first-line treatment modality in this patient population.

Targeting the mTOR signaling pathway in neuroendocrine tumors

OPINION STATEMENT

Neuroendocrine tumors (NETs) are a heterogeneous group of malignancies characterized by variable but most often indolent biologic behavior. Well-differentiated NETs can be broadly classified as either carcinoid or pancreatic NET. Although they have similar characteristics on routine histologic evaluation, the 2 tumor subtypes have different biology and respond differently to treatment, with most therapeutic agents demonstrating higher response rates in pancreatic NETs compared with carcinoid. Until recently, systemic treatment options for patients with advanced NETs were limited. However, improvements in our understanding of signaling pathways involved in the pathogenesis, growth, and spread of NETs have translated into an expansion of treatment options. Aberrant signaling through the mechanistic pathway of rapamycin (mTOR) pathway has been implicated in neuroendocrine tumorigenesis. Additionally, altered expression of mTOR pathway components has been observed in NETs and has been associated with clinical outcomes. Targeting the mTOR pathway has emerged as an effective treatment strategy in the management of advanced NETs. In a randomized, placebo-controlled study of patients with advanced pancreatic NET, treatment with the mTOR inhibitor everolimus was associated with improved progression-free survival (PFS). Largely based upon these data, everolimus has been approved in the United States and Europe for the treatment of patients with advanced pancreatic NET. The activity of everolimus remains under investigation in patients with carcinoid tumors. In a randomized study of patients with advanced carcinoid tumors associated with carcinoid syndrome, the addition of everolimus to octreotide was associated with improved PFS compared with octreotide. However, the results did not meet the prespecified level of statistical significance based on central review of radiographic imaging. Results from a randomized study examining the efficacy of everolimus in patients with nonfunctional gastrointestinal and lung NETs are awaited. In addition, further investigation is needed to determine whether primary tumor site or other clinical and molecular factors can impact response to mTOR inhibition. Although everolimus can slow tumor progression, significant tumor reduction is rarely obtained. Targeting multiple signaling pathways is a treatment strategy that may provide better tumor control and overcome resistance mechanisms involved with targeting a single pathway. Results of ongoing and future studies will provide important information regarding the added benefit of combining mTOR inhibitors with other targeted agents, such as VEGF pathway inhibitors, and cytotoxic chemotherapy in the treatment of advanced NETs.

Multicenter retrospective analysis of systemic chemotherapy for advanced neuroendocrine carcinoma of the digestive system

This study analyzed outcomes of systemic chemotherapy for advanced neuroendocrine carcinoma (NEC) of the digestive system. Clinical data from 258 patients with unresectable or recurrent NEC of the gastrointestinal tract (GI) or hepato-biliary-pancreatic system (HBP), who received chemotherapy, were collected from 23 Japanese institutions and analyzed retrospectively. Patients had primary sites in the esophagus (n = 85), stomach (n = 70), small bowel (n = 6), colorectum (n = 31), hepato-biliary system (n = 31) and pancreas (n = 31). Median overall survival (OS) was 13.4 months the esophagus, 13.3 months for the stomach, 29.7 months for the small bowel, 7.6 months for the colorectum, 7.9 months for the hepato-biliary system and 8.5 months for the pancreas. Irinotecan plus cisplatin (IP) and etoposide plus cisplatin (EP) were most commonly selected for GI-NEC and HBP-NEC. For patients treated with IP/EP (n = 160/46), the response rate was 50/28% and median OS was 13.0/7.3 months. Multivariate analysis among patients treated with IP or EP showed that the primary site (GI vs HBP; hazard ratio [HR] 0.58, 95% confidence interval [CI] 0.35-0.97) and baseline serum lactate dehydrogenase levels (not elevated vs elevated; HR 0.65, 95% CI 0.46-0.94) were independent prognostic factors for OS, while the efficacy of IP was slightly better than for EP (HR 0.80, 95% CI 0.48-1.33; P = 0.389). IP and EP are the most common treatment regimens for NEC of the digestive system. HBP primary sites and elevated lactate dehydrogenase levels are unfavorable prognostic factors for survival. A randomized controlled trial is required to establish the appropriate chemotherapy regimen for advanced NEC of the digestive system. This study was registered at UMIN as trial number 000005176.

Real-world study of everolimus in advanced progressive neuroendocrine tumors

Everolimus is a valid therapeutic option for neuroendocrine tumors (NETs); however, data in a real-world setting outside regulatory trials are sparse. The aim of this study was to determine everolimus tolerability and efficacy, in relation to previous treatments, in a compassionate use program. A total of 169 patients with advanced progressive NETs treated with everolimus were enrolled, including 85 with pancreatic NETs (pNETs) and 84 with nonpancreatic NETs (non-pNETs). Previous treatments included somatostatin analogs (92.9%), peptide receptor radionuclide therapy (PRRT; 50.3%), chemotherapy (49.7%), and PRRT and chemotherapy (22.8%). Overall, 85.2% of patients experienced adverse events (AEs), which were severe (grade 3-4) in 46.1%. The most frequent severe AEs were pneumonitis (8.3%), thrombocytopenia (7.7%), anemia (5.3%), and renal failure (3.5%). In patients previously treated with PRRT and chemotherapy, a 12-fold increased risk for severe toxicity was observed, with grade 3-4 AEs reported in 86.8% (vs. 34.3% in other patients). In addition, 63.3% of patients required temporarily everolimus discontinuation due to toxicity. Overall, 27.8% of patients died during a median follow-up of 12 months. Median progression-free survival (PFS) and overall survival (OS) were 12 months and 32 months, respectively. Similar disease control rates, PFS, and OS were reported in pNETs and non-pNETs. In the real-world setting, everolimus is safe and effective for the treatment of NETs of different origins. Higher severe toxicity occurred in patients previously treated with systemic chemotherapy and PRRT. This finding prompts caution when using this drug in pretreated patients and raises the issue of planning for everolimus before PRRT and chemotherapy in the therapeutic algorithm for advanced NETs.

Topotecan monotherapy in heavily pretreated patients with progressive advanced stage neuroendocrine carcinomas

Background: Neuroendocrine carcinomas (WHO grade 3) are highly aggressive tumors with an immense tendency to metastasize and with a poor prognosis. In advanced disease, there is no standard treatment beyond first-line platin/etoposide-based chemotherapy. Topotecan is widely used as second-line treatment in small cell lung cancer, which also responds markedly on first-line platin/etoposide. Hence, we investigated the feasibility of topotecan in previously treated patients with neuroendocrine carcinomas.

Material and Methods: Retrospective analysis of 22 patients with disseminated and progressive neuroendocrine carcinomas (Ki67>20%, G3) successively treated with oral topotecan 2.3 mg/m² d1-5 every 3 weeks. All patients had previously received treatment with carboplatin/etoposide. Demographic, clinical and pathological features were recorded. CT-evaluations according to RECIST 1.1 were performed after every three courses. Hematological toxicity was assessed by CTC-criteria.

Results: Twenty-two eligible patients received a median of 2 courses [range1-6]. Median age: 65 years [35-77]. Male/female: 11/11. Median Ki-67 index: 95% [25-100%]. Median number previous chemotherapy regimens: 2 [1-3]. All patients were evaluable for response: Five achieved stable disease (SD) and 17 progressed (PD). The median overall survival for the 22 patients was 3.2 months and the median progression-free survival was 2.1 months. The one-year survival was 18%. There were no treatment related deaths. The treatment was well tolerated: Haematological toxicity comprised leukopenia CTC grade 3 (14%), grade 4 (9%) and thrombocytopenia grade 3 (14%).

Conclusion: Topotecan monotherapy shows modest anti-tumor activity in heavily treated patients with progressive disseminated G3 neuroendocrine carcinomas.

Gastric neuroendocrine neoplasms and related precursor lesions

Gastric neuroendocrine neoplasms (NENs) are a heterogeneous group of tumours showing different clinicopathological features and behaviour, implying a wide spectrum of therapeutic options. They are currently classified using the 2010 WHO classification of digestive neuroendocrine neoplasms into G1-neuroendocrine tumours (NETs), G2-NETs, neuroendocrine carcinomas (NECs) and mixed adenoneuroendocrine carcinomas (MANECs). However, most gastric NENs are composed of ECL-cells (ECL-cell NETs) that can be preceded by ECL-cell hyperplastic and dysplastic lesions, whose oncologic potential has not yet been completely elucidated. ECL-cell NETs differ considerably in terms of prognosis depending on the proliferative status and clinicopathological background. The integration of both aspects in the diagnostic pathway may help to better classify tumours in different prognostic categories, especially when diagnosing them in small bioptic specimens. NECs are all poorly differentiated, highly aggressive carcinomas, while MANECs can show different morphological features that are directly associated with different prognoses. Precursor lesions of such carcinomas are not entirely understood. In this review, the clinicopathological features of gastric NENs and related precursor lesions will be described to give the reader a comprehensive overview on this topic.

High-grade poorly differentiated neuroendocrine carcinomas of the gastroenteropancreatic system: from morphology to proliferation and back

Poorly differentiated neuroendocrine carcinomas (PDNECs) of the gastroenteropancreatic system (GEP) are a heterogeneous group of aggressive malignancies with a high propensity for distant metastases and an ominous prognosis. They have traditionally been divided into small and large cell subtypes on morphological grounds. However, histological diagnosis needs to be supported by immunohistochemistry to avoid possible misdiagnoses either with the more frequent poorly differentiated adenocarcinomas and squamous cell carcinomas or with lymphomas and mesenchymal neoplasms. Although it is well known that GEP PDNECs are associated with a poor prognosis, data from some published studies seem to suggest that there is a fraction of patients with PDNECs who have better survival than expected. GEP PDNECs are currently classified according to the criteria proposed in the 2010 WHO classification. They are simply called neuroendocrine carcinomas (NECs) and are defined by mitotic count >20 × 10 HPF and/or Ki-67 labeling index >20 %. However, a few recent papers have indicated that some NECs, as defined by the 2010 WHO scheme, do not show a poorly differentiated morphology as expected. This category seems to show a better prognosis and, especially, does not respond to cisplatin-based chemotherapy, which represents the goal standard therapeutic approach to high-grade PDNECs. In the present review, the main morphological, immunohistochemical, and prognostic features will be discussed as well as the opportunity to introduce a new category characterized by well to moderately differentiated morphology associated with high proliferation (mitotic count >20 × 10 HPF and/or Ki-67 index >20 %).

The 2010 WHO classification of digestive neuroendocrine neoplasms: a critical appraisal four years after its introduction

This paper briefly illustrates the basis, rules of application, and present outcome of the current World Health Organization (WHO) classification for neuroendocrine neoplasms. Established in 2010 upon the proposal from the European Neuroendocrine Tumor Society (ENETS), the WHO 2010 fostered some definitional changes (most notably the use of neuroendocrine tumor (NET) instead of carcinoid) and indicated the tools of grading and staging. Specific rules for its application were also defined. The data generated from the use of WHO 2010 classification substantially endorsed its rules and prognostic efficacy. In addition, the application demonstrated some issues, among which are the possible re-definition of the cutoff for grading G1 vs G2, as well as the possible identification of cases with somewhat different clinical behavior within the G3 neuroendocrine cancer class. Overall, since the recent introduction of WHO 2010 grading and staging, it appears wise to keep the current descriptors to avoid unnecessary confusion and to generate comparable data. Homogenous data on large series are ultimately needed to solve such issues.

Multiple scalp metastases from colonic neuroendocrine carcinoma: case report and literature review

Background

Colonic neuroendocrine neoplasms (NENs) are relatively rare tumors with an incidence rate of 0.11–0.21/100,000. NENs account for approximately 0.4% of colorectal neoplasms. Cutaneous metastases of colonic neuroendocrine carcinomas (NECs) are very infrequent, while cases of scalp metastasis are even fewer. Cutaneous metastases are more rare than visceral metastases and usually develop later; therefore, cutaneous metastases as initial distant metastases can be easily overlooked. This is the second case report of a colonic NEC with scalp metastasis. Compared with the previous case, in this instance scalp metastasis developed before visceral metastasis, and the cutaneous lesions were confined to the scalp alone.

Case presentation

A 62-year-old Chinese man, who had undergone radical surgery for a “locoregional” colonic NEC one and half months before, came to our hospital for adjuvant chemotherapy. We found multiple scalp nodules during physical examination. Moreover, these nodules had occurred and had not been detected prior to the patient undergoing radical surgery. The scalp nodules proved to be metastases from colonic NEC as determined using pathological and immunohistochemical examinations following lumpectomy. After one and half months, visceral metastases were detected in this patient. Ultimately, the patient died two months later.

Conclusions

In this report an unusual case of a colonic NEC with initial distant metastasis confined to the scalp is presented. This case is unusual because of the development of cutaneous metastasis before visceral metastasis. The scalp metastasis were initially overlooked, leading to inaccurate staging and radical surgery that was not curative. This demonstrates that distant metastasis can occur during the early phase of tumor growth in these aggressive lesions. Thus, the possibility of distant metastases should be assessed in the initial work up to avoid mistaken clinical staging especially when distant metastases occur only in skin.

Gastroenteropancreatic high-grade neuroendocrine carcinoma

Gastroenteropancreatic (GEP) neuroendocrine neoplasms are classified as low-grade, intermediate-grade, and high-grade tumors based on morphologic criteria and the proliferation rate. Most studies have been conducted in patients with well differentiated (low-grade to intermediate-grade) neuroendocrine tumors. Data are substantially scarcer on poorly differentiated, high-grade neuroendocrine carcinoma (NEC), which includes the entities of small cell carcinoma and large cell NEC. A literature search of GEP-NEC was performed. Long-term survival was poor even among patients who presented with localized disease. Several studies highlighted heterogeneity within the high-grade NEC category and a need for the further identification of discreet prognostic and predictive groups. Tumors with a Ki-67 proliferation index <55% were less responsive to platinum-based chemotherapy, and patients with such tumors or with well differentiated morphology had better survival than patients who had tumors with poorly differentiated morphology or a higher Ki-67 index. Treatment options beyond platinum-based chemotherapy are emerging. A revision of the World Health Organization high-grade NEC classification seems to be necessary based on recent data. Platinum-based chemotherapy may not be the optimal treatment for patients who have GEP-NEC with a moderately high proliferation rate. Adequate diagnostic and prognostic stratifications constitute the basis for future progress.

A retrospective review of 126 high-grade neuroendocrine carcinomas of the colon and rectum

BACKGROUND

High-grade neuroendocrine carcinomas (HGNECs) of the colon and rectum are rare, constituting less than 1 % of colorectal cancers. The purpose of this study was to identify the natural history and oncologic outcomes of this disease, describe the use of surgery, and determine the clinical and pathological factors associated with outcomes.

METHODS

Following Institutional Review Board approval, patients with HGNEC were identified from our institutional database. Patient charts and pathology reports were analyzed retrospectively for clinical and pathological factors.

RESULTS

A total of 126 patients with a median follow-up of 9 months were identified. Median survival was 13.2 months, and 85 (67 %) patients had metastatic disease at diagnosis. Three-year overall survival (OS) was 5 and 18 % for patients with and without metastatic disease, respectively. Factors associated with improved OS on multivariable analysis were absence of metastatic disease and presence of an adenocarcinoma component within the tumor. In patients with metastatic disease, response to chemotherapy was the only factor associated with survival. In patients with localized disease, an adenocarcinoma component within the tumor was the only factor associated with survival. Resection of tumor was not associated with survival in either localized or metastatic disease.

CONCLUSION

High-grade colorectal NECs are extremely aggressive tumors with poor prognosis. Patients appear to have a marginally better prognosis if they present without metastatic disease, have an adenocarcinoma component within their tumor, or respond to chemotherapy. Surgery, particularly in the presence of metastatic disease, may not offer a survival benefit for the majority of patients.

Poorly differentiated neuroendocrine carcinomas of the pancreas: a clinicopathologic analysis of 44 cases

BACKGROUND

In the pancreas, poorly differentiated neuroendocrine carcinomas include small cell carcinoma and large cell neuroendocrine carcinoma and are rare; data regarding their pathologic and clinical features are very limited.

DESIGN

A total of 107 pancreatic resections originally diagnosed as poorly differentiated neuroendocrine carcinomas were reassessed using the classification and grading (mitotic rate/Ki67 index) criteria put forth by the World Health Organization in 2010 for the gastroenteropancreatic system. Immunohistochemical labeling for neuroendocrine and acinar differentiation markers was performed. Sixty-three cases were reclassified, mostly as well-differentiated neuroendocrine tumor (NET) or acinar cell carcinoma, and eliminated. The clinicopathologic features and survival of the remaining 44 poorly differentiated neuroendocrine carcinomas were further assessed.

RESULTS

The mean patient age was 59 years (range, 21 to 82 y), and the male/female ratio was 1.4. Twenty-seven tumors were located in the head of the pancreas, 3 in the body, and 11 in the tail. The median tumor size was 4 cm (range, 2 to 18 cm). Twenty-seven tumors were large cell neuroendocrine carcinomas, and 17 were small cell carcinomas (mean mitotic rate, 37/10 and 51/10 HPF; mean Ki67 index, 66% and 75%, respectively). Eight tumors had combined components, mostly adenocarcinomas. In addition, 2 tumors had components of well-differentiated NET. Eighty-eight percent of the patients had nodal or distant metastatic disease at presentation, and an additional 7% developed metastases subsequently. Follow-up information was available for 43 patients; 33 died of disease, with a median survival of 11 months (range, 0 to 104 mo); 8 were alive with disease, with a median follow-up of 19.5 months (range, 0 to 71 mo). The 2- and 5-year survival rates were 22.5% and 16.1%, respectively.

CONCLUSIONS

Poorly differentiated neuroendocrine carcinoma of the pancreas is a highly aggressive neoplasm, with frequent metastases and poor survival. Most patients die within less than a year. Most (61%) are large cell neuroendocrine carcinomas. Well-differentiated NET and acinar cell carcinoma are often misdiagnosed as poorly differentiated neuroendocrine carcinoma, emphasizing that diagnostic criteria need to be clearly followed to ensure accurate diagnosis.