Rare neuroendocrine tumours: results of the surveillance of rare cancers in Europe project

The Role of Neoadjuvant Immunotherapy in the Management of Merkel Cell Carcinoma with Clinically Detected Regional Lymph Node Metastasis

BACKGROUND

Immunotherapy is emerging as a promising option for certain locally advanced and metastatic cutaneous malignancies. However, the role of neoadjuvant immunotherapy (NIO) in Merkel cell carcinoma (MCC) with clinically detected regional lymph node metastasis (CDRLNM) has not been fully elucidated.

METHODS

For this study, MCC patients with CDRLNM who underwent surgical excision were selected from the National Cancer Database (NCDB). Those who received NIO were propensity-matched with those who did not, and Kaplan-Meier analysis was used to compare overall survival (OS).

RESULTS

Of the 1809 selected patients, 356 (19.7%) received NIO followed by wide excision (n = 352, 98.9%) or amputation (n = 4, 1.1%). The rate of complete pathologic response for the primary tumor (ypT0) was 45.2%. Only 223 patents (63.4%) also underwent lymph node dissection (LND). The complete pathologic nodal response (ypN0) rate for these patients was 17.9%. A pathologic complete response of both the primary tumor and the nodal basin (ypT0 ypN0) was seen in 16 of the 223 patients who underwent both primary tumor surgery and LND. Subsequently, 151 pairs were matched between the NIO and no-NIO groups (including only patients with LND). Kaplan-Meier analysis demonstrated a significant OS improvement with NIO (median not reached vs. 35.0 ± 8.0 months; p = 0.025). The 5-year OS was 57% in the NIO group versus 44% in no-NIO group (p = 0.021).

CONCLUSION

The study suggests that NIO in MCC with CDRLNM provides improved OS in addition to promising rates of primary complete response, which could change the profile of surgical resection. This supports ongoing clinical trials exploring the use of NIO in MCC.

[Periocular Merkel Cell Carcinoma - an overview of clinical aspects and current therapeutic options]

Merkel cell carcinoma (MCC) is a rare but highly aggressive and rapidly expanding malignant skin tumor. It affects the periocular region in approximately 10% of cases. The current treatment recommendation for resectable non-metastatic MCC comprises total surgical excision; however, lymph node or distant metastases are often already present by the time of the diagnosis. Since an immune checkpoint inhibitor therapy with avelumab was first approved for MCC in 2016, there has been considerable improvement in mean survival compared to cytostatic therapy; at the same time, there has been a reduction in serious treatment-associated adverse events. Other immune checkpoint inhibitors are currently still in clinical trials, with very promising initial results. Because of the complexity of the diagnosis, treatment, and prognosis, it is essential that MCC patients receive interdisciplinary care in a specialized center including consultation with a tumor review board.

Merkel-cell carcinoma: ESMO-EURACAN Clinical Practice Guideline for diagnosis, treatment and follow-up

•This ESMO Clinical Practice Guideline provides key recommendations for managing Merkel-cell carcinoma (MCC). •Recommendations are based on available scientific data and the multidisciplinary group of experts’ collective opinion. •The guideline covers clinical and pathological diagnosis, staging and risk assessment, treatment and follow-up. •Algorithms for the management of locoregional and inoperable/metastatic disease are provided. •A multidisciplinary team with a high level of expertise in MCC should diagnose and make decisions about therapy.

Quantitative uptake in 99m Tc-EDDA/HYNIC-TOC somatostatin receptor imaging - the effect of long-acting release somatostatin analogue therapy

PURPOSE

Withdrawal of long-acting release somatostatin analogue (LAR-SSA) treatment before somatostatin receptor imaging is based on empirical reasoning that it may block uptake at receptor sites. This study aims to quantify differences in uptake of 99m Tc-EDDA/HYNIC-TOC between patients receiving LAR-SSA and those who were not.

METHODS

Quantification of 177 patients (55 on LAR-SSA) imaged with 99m Tc-EDDA/HYNIC-TOC was performed, with analysis of pathological tissue and organs with physiological uptake using thresholded volumes of interest. Standardised uptake values (SUVs) and tumour/background (T/B) ratios were calculated and compared between the two patient groups.

RESULTS

SUVs were significantly lower for physiological organ uptake for patients on LAR-SSA (e.g. spleen: SUV max 13.3 ± 5.9 versus 33.9 ± 9.0, P  < 0.001); there was no significant difference for sites of pathological uptake (e.g. nodal metastases: SUV max 19.2 ± 13.0 versus 17.4 ± 11.5, P  = 0.552) apart from bone metastases (SUV max 14.1 ± 13.5 versus 7.7 ± 8.0, P  = 0.017) where it was significantly higher.

CONCLUSION

LAR-SSA has an effect only on physiological organ uptake of 99m Tc-EDDA/HYNIC-TOC, reducing uptake. It has no significant effect on pathological uptake for most sites of primary and metastatic disease. This should be taken into account if making quantitative measurements, calculating T/B ratios or assigning Krenning Scores. There is the potential for improved dosimetric results in Peptide Receptor Radionuclide Therapy by maintaining patients on LAR-SSA.

Merkel cell carcinoma: epidemiology, clinical features, diagnosis and treatment of a rare disease

Merkel cell carcinoma is a rare skin cancer with neuroendocrine differentiation. The risk factors include sun exposure, advanced age, immunosuppression (such as transplant recipients, patients with lymphoproliferative neoplasms, or patients with HIV), and Merkel cell polyomavirus infection. Clinically, Merkel cell carcinoma appears as a cutaneous or subcutaneous plaque or nodule, but this tumor diagnosis is rarely made clinically. Therefore, histopathology and immunohistochemistry are usually necessary. Primary tumors without evidence of metastases are treated with complete surgical excision and appropriate surgical margins. The presence of occult metastasis in a lymph node is frequent and a sentinel lymph node biopsy should be performed. Postoperative adjuvant radiotherapy increases local tumor control. Recently, agents that block the PD-1/PD-L1 pathway have shown objective and durable tumor regression in patients with advanced solid malignancies. The first anti-PD-L1 antibody used in patients with Merkel cell carcinoma was avelumab, but pembrolizumab and nivolumab have also shown efficacy. This article describes the current state of knowledge of the epidemiology, diagnosis, and staging of Merkel cell carcinoma, as well as new strategies for its systemic treatment.

Trends in incidence, treatment and survival of Merkel cell carcinoma in England 2004-2018: a cohort study

BACKGROUND

Merkel cell carcinoma (MCC) is a rare tumour with neuroendocrine differentiation and high associated mortality. Studies that describe the epidemiology of MCC are often limited by small sample size, short duration of follow-up, absence of nationwide data and paucity of data on different risk factors.

OBJECTIVES

To determine the incidence, demographics and survival for MCC in England between 2004 and 2018.

METHODS

This national retrospective cohort study identified all cases of MCC in England from 2004 to 2018 using national population-based data from the National Disease Registration Service. Crude counts, European age-standardized incidence rates (EASRs) and joinpoint analysis were conducted. Patient demographics and treatments received were described. Multivariable Cox regression analysis was used to study risk factors for MCC-specific mortality, by including a priori defined demographic factors, tumour characteristics and immunosuppression. Treatment data were not included in the Cox regression analysis.

RESULTS

A total of 3775 MCC tumours were registered. The median age at diagnosis was 81 years (interquartile range 74-87). Overall, 96·6% of patients identified as White ethnicity, and 8·3% of patients were immunosuppressed. The most common site was the face (27·4%). Patients most often presented with stage one disease (22·8%); however, stage was unknown in 31·0%. In total, 80·7% of patients underwent surgical excision, 43·5% radiotherapy and 9·2% systemic therapy. The EASR increased from 0·43 per 100 000 person-years (PYs) to 0·65 per 100 000 person-years between 2004 and 2018, representing a significant annual percentage change of 3·9%. The EASR was greater in men than in women for all years, with an overall male-to-female ratio of 1·41 : 1. The highest EASR was in South West England. Five-year disease-specific survival was 65·6% [95% confidence interval (CI) 63·8-67·4], with a median follow-up of 767 days. MCC-specific mortality increased with age [hazard ratio (HR) 1·02, 95% CI 1·02-1·03], deprivation (HR 1·43, 95% CI 1·16-1·76), immunosuppression (HR 2·80, 95% CI 2·34-3·34) and stage at diagnosis (HR 8·24, 95% CI 5·84-11·6).

CONCLUSIONS

This study presents the largest national MCC dataset in Europe, and the most complete reporting of MCC incidence and survival ever published. With the EASR of MCC increasing and high associated mortality, this study encourages further research into the pathology, diagnosis and therapeutic options for MCC to support management guidelines.

Periocular Merkel Cell Carcinoma - An Overview of Clinical Aspects and Current Treatment Options

Merkel cell carcinoma (MCC) is a rare but highly aggressive and rapidly expanding malignant skin tumor. It affects the periocular region in approximately 10% of cases. The current treatment recommendation for resectable non-metastatic MCC comprises total surgical excision; however, lymph node or distant metastases are often already present by the time of the diagnosis. Since an immune checkpoint inhibitor therapy with avelumab was first approved for MCC in 2016, there has been considerable improvement in mean survival compared to cytostatic therapy; at the same time, there has been a reduction in serious treatment-associated adverse events. Other immune checkpoint inhibitors are currently still in clinical trials, with very promising initial results. Because of the complexity of the diagnosis, treatment, and prognosis, it is essential that MCC patients receive interdisciplinary care in a specialized center including consultation with a tumor review board.

An Intestinal Type Gastric Neuroendocrine Tumor: A Case Report

Neuroendocrine tumors (NETs) represent a diverse set of malignancies, originating from the neuroendocrine cells dispersed throughout the body. Their symptoms are associated with the secretion of bioactive peptides by tumor cells. Five-year survival rates depend on the disease stage: 93% for local, 74% for regional, and 19% for metastatic disease. This report describes a case involving a 64-year-old male patient, who was enduring high blood pressure and anemia. His symptomatology included frequent fainting and bloody vomiting without prior bleeding, coupled with persistent abdominal pain and weight loss. A complete blood count revealed microcytic anemia. His condition improved postoperatively after the transfusion of two units of packed red blood cells, normalizing all parameters. Further biochemistry and serology tests did not provide significant insights. However, an upper endoscopy unveiled a deep ulcer below the gastroesophageal junction with ulcer desquamation. A combination of clinical, laboratory, and radiographic data initially indicated a gastric carcinoma of the intestinal type, characterized by extensive extracellular mucin secretion. The surgical intervention led to the extraction of multiple tumors from lymph nodes, culminating in a postoperative diagnosis of a gastrointestinal (GI) mesenchymal tumor. NETs predominantly manifest in the GI tract, initiating primarily in the small intestine but can also originate in the stomach, appendix, colon, and other parts of the GI tract. Their development from neuroendocrine cells enables them to produce high concentrations of hormone-like substances such as neuropeptides and amines.

Merkel Cell Carcinoma-Update on Diagnosis, Management and Future Perspectives

MCC is a rare but highly aggressive skin cancer. The identification of the driving role of Merkel cell polyomavirus (MCPyV) and ultraviolet-induced DNA damage in the oncogenesis of MCC allowed a better understanding of its biological behavior. The presence of MCPyV-specific T cells and lymphocytes exhibiting an 'exhausted' phenotype in the tumor microenvironment along with the high prevalence of immunosuppression among affected patients are strong indicators of the immunogenic properties of MCC. The use of immunotherapy has revolutionized the management of patients with advanced MCC with anti-PD-1/PD L1 blockade, providing objective responses in as much as 50-70% of cases when used in first-line treatment. However, acquired resistance or contraindication to immune checkpoint inhibitors can be an issue for a non-negligible number of patients and novel therapeutic strategies are warranted. This review will focus on current management guidelines for MCC and future therapeutic perspectives for advanced disease with an emphasis on molecular pathways, targeted therapies, and immune-based strategies. These new therapies alone or in combination with anti-PD-1/PD-L1 inhibitors could enhance immune responses against tumor cells and overcome acquired resistance to immunotherapy.

Epidemiology of Merkel Cell Polyomavirus Infection and Merkel Cell Carcinoma

Merkel cell polyomavirus (MCPyV) is a ubiquitous virus replicating in human dermal fibroblasts. MCPyV DNA can be detected on healthy skin in 67−90% of various body sites, and intact virions are regularly shed from the skin. Infection occurs early in life, and seropositivity increases from 37 to 42% in 1- to 6-year-olds to 92% in adults. Merkel cell carcinoma (MCC) is a rare but very aggressive neuroendocrine tumor of the skin. It develops mainly on sun-exposed areas as a fast-growing, reddish nodule. Two MCC entities exist: about 80% of MCC are MCPyV-associated. Tumorigenesis is driven by viral integration into the host genome and MCPyV oncogene expression. In MCPyV-negative MCC, UV radiation causes extensive DNA damage leading to the deregulation of the cell cycle. In recent decades, MCC incidence rates have increased worldwide, e.g., in the United States, from 0.15 in 1986 to 0.7/100,000 in 2016. Risk factors for the development of MCC include male sex, older age (>75 years), fair skin, intense UV exposure, and immunosuppression. Projections suggest that due to aging populations, an increase in immunosuppressed patients, and enhanced UV exposure, MCC incidence rates will continue to rise. Early diagnosis and prompt treatment are crucial to reducing high MCC morbidity and mortality.

A modified mTNM staging system based on lymph node ratio for colon neuroendocrine tumors: A recursive partitioning analysis

BACKGROUND

In the current tumor-lymph node-metastasis (TNM) staging system for colon neuroendocrine tumors, lymph node status is divided into N1 and N0. An assessment of the lymph node ratio (LNR) and a proposal for a modified mTNM staging system were the objectives of this study.

METHODS

Selecting the optimal cut-off value of LNR was done using X-tile. A Cox regression model and the Kaplan-Meier method were performed to calculate patient cancer-specific survival in the Surveillance, Epidemiology and End Results cohort. Recursive partitioning analysis was used to improve TNM staging.

RESULTS

The study included 674 patients. The current TNM staging system showed inadequate discriminatory power between stage I and stage II patients (p = 0.088). The optimal cut-off value was determined as 0.6 for LNR. Based on multivariate Cox regression analysis, the modified mN classification could be classified into mN 0 (LNR = 0.00), mN 1 (LNR = 0.01-0.60), and mN 2 (LNR > 0.60), and was found to be an independent factor affecting prognosis (p < 0.001). Using the American Joint Committee on Cancer T and modified mN classifications, the modified mTNM system was constructed, and it exhibited better prognostic discriminatory power ability than the traditional TNM system (C-index: 0.587 vs. 0.665).

CONCLUSIONS

Our study determined that LNR is a prognostic factor in colon NET patients. In addition, to more accurately assess the prognosis of colon NET patients, we proposed a modified mTNM staging system.

A Real-World Observational Study of the Use and Associated Costs of Treating Neuroendocrine Tumors With Somatostatin Analogs in Canada

OBJECTIVES

Somatostatin analogs (SSAs; lanreotide autogel and octreotide long-acting release) are used to treat neuroendocrine tumors; however, factors that influence SSA use are unclear.

METHODS

This real-world, observational study collected data from private/public pharmacy claims for patients using SSAs in Canada. Data relating to dosing regimens, injection burden, treatment persistence, and costs were retrospectively analyzed for treatment-naive patients.

RESULTS

Overall, 1545 patients were included in the analysis of dosing regimens, 908 for injection burden, 453 for treatment persistence, and 903 for treatment-associated costs. Compared with lanreotide, treatment with octreotide long-acting release was more likely associated with treatment above the maximum recommended dose (odds ratio, 16.2; 95% confidence interval, 4.3-136.2; P < 0.0001), higher weighted average long-acting SSA injection burden (13.4 vs 12.5, P < 0.0001), and a higher number of rescue medication claims per patient (0.22 vs 0.03, P < 0.0001). Treatment with lanreotide autogel was associated with greater treatment persistence (hazard ratio, 0.58; 95% confidence interval, 0.42-0.80; P = 0.001) and lower mean annual costs of treatment than octreotide long-acting release (Canadian dollars $27,829.35 vs $31,255.49; P < 0.0001).

CONCLUSIONS

These findings provide valuable insight into SSA use in clinical settings and may inform treatment selection.

Neuroendocrine Tumors: An Analysis of Prevalence, Incidence, and Survival in a Hospital-Based Study in Ecuador

Neuroendocrine tumors (NETs) represent a heterogeneous malignancy group of neoplasms, with a limited amount of data from Latin America. Thus, this observational study aimed to provide data about the prevalence, incidence, and survival rates for NET in Ecuadorian hospitals. The study was conducted using data from the Society for the Fight Against Cancer (SOLCA). We evaluated patients with NETs (2000−2020) using the HJ-Biplot method and Cox proportional hazards. Annual age-adjusted incidence and limited-duration prevalence in multivariable analyses as well as hazard ratios (HRs) for mortality and survival were obtained. In the years 2000−2020, the age-adjusted incidence rate increased by 9-fold in the stomach and by 7-fold in the breast. The incidence rates were 1.38 per 100,000 persons in the lung and at 1.79 per 100,000 persons in gastroenteropancreatic sites (rectum, stomach, and pancreas). The prevalence increased from 0.0027% in 2000 to 0.0736% in 2019 and 0.0245% in 2020. Overall survival was worse for metastatic NETs (HR, 4.061; 95% CI, 1.932−8.540; p < 0.001) and advanced local NETs (HR, 2.348; 95% CI, 1.007−5.475 p < 0.048) than for localized NETs. In conclusion, the NET incidence increased in the last 20 years and survival decreased over time, especially for metastatic tumors in the pancreas and the nostril.

Real-world comparison of healthcare resource utilization and costs of [177Lu]Lu-DOTA-TATE in patients with progressive neuroendocrine tumors in England: a matched cohort analysis using data from the hospital episode statistics dataset

OBJECTIVE

To explore the healthcare resource utilization (HCRU) and costs for patients with progressive gastroenteropancreatic neuroendocrine tumors (GEP-NETs) treated with [¹⁷⁷Lu]Lu-DOTA-TATE and matched patients treated with somatostatin analogs (SSAs), chemotherapy, or targeted therapies.

METHODS

Hospital Episode Statistics (HES) dataset 2016-2018 was used to compare HCRU and costs between the two cohorts. The [¹⁷⁷Lu]Lu-DOTA-TATE cohort included patients assigned with a diagnosis code relevant to GEP-NET, a procedure code for imaging or SSAs, and a subsequent code for radionuclide therapy. The non-[¹⁷⁷Lu]Lu-DOTA-TATE cohort included patients assigned with a diagnosis code relevant to GEP-NET who had an increased frequency of SSAs or switched from SSAs to chemotherapy or targeted therapies. Cohorts were matched on propensity scores with sex, age at disease progression, and Charlson Comorbidity Index as parameters. Healthcare Resource Group codes were used for costing.

RESULTS

A total of 199 matched patients were included. The [¹⁷⁷Lu]Lu-DOTA-TATE cohort had lower overall costs (£1,882,028 vs. £3,016,321; p < .0001), non-elective inpatient spells (289 vs. 611 days) and costs (£849,569 vs. £1,707,109; p < .0001 for both), Accident & Emergency costs (£41,978 vs. £62,480; p = .0013), and average length of stay for overall inpatient spells (14.2 vs. 23.3 days; p = .1092) compared with the non-[¹⁷⁷Lu]Lu-DOTA-TATE cohort.

CONCLUSIONS

These analyses indicate significantly lower overall costs and HCRU for progressive GEP-NET patients treated with [¹⁷⁷Lu]Lu-DOTA-TATE. Current research reveals that future real-world analyses would further benefit from using additional databases linked to the HES dataset such as the Clinical Practice Research Datalink and/or National Cancer Registration and Analysis Service database.

Primary Neuroendocrine Tumor of the Breast: Current Understanding and Future Perspectives

Primary neuroendocrine carcinoma of the breast (NECB) is characterized with heterogeneity, rarity, and poor differentiation, which is probably an underestimated subtype of breast cancer, including small cell NECs and large cell NECs. The diagnostic criteria for NECB have been constantly updated as the disease changes and the understanding increases. According to the latest WHO Classification, primary neuroendocrine neoplasm (NEN) of the breast consists of well-differentiated neuroendocrine tumors (NET), extremely aggressive neuroendocrine carcinomas (NEC) as well as invasive breast cancers of no special type (IBCs-NST) with neuroendocrine differentiation. The accurate diagnosis of NECB remains a challenge for its low incidence, which needs multi-disciplinary methods. For the rarity of the disease, there is a lack of large samples and prospective clinical research. For these invasive tumors, there are no standardized therapeutic guidelines or norms, and the treatment often refers to nonspecific breast cancer. In addition, the prognosis of such patients remains unknown. In 2003, the World Health Organization (WHO) listed NECB as an independent entity for the first time, while few features of NECB were clarified. In this review, it presents the WHO Classification, clinicopathologic characteristics, diagnosis, treatment, and prognosis of these patients. In addition, it summarizes the latest studies on molecular features of NECB, aiming to provide new therapeutic perspectives for the disease.

Impact of Insulin Therapies on Cancer Incidence in Type 1 and Type 2 Diabetes: A Population-Based Cohort Study in Reggio Emilia, Italy

Simple Summary

The aim of this population-based study was to assess the impact of insulin treatment on cancer incidence in subjects with type 1 or type 2 diabetes in Italy. We found that insulin use was associated with a 20% excess for all sites cancer incidence among people with type 2 diabetes, while people with type 1 diabetes did not show any excess. Liver, pancreatic, bladder, and neuroendocrine cancers seem to be the sites with strongest association.

Abstract

Objective: To assess the effect of insulin on cancer incidence in type 1 (T1DM) and type 2 diabetes (T2DM). Methods: The cohort included all 401,172 resident population aged 20–84 in December 2009 and still alive on December 2011, classified for DM status. Drug exposure was assessed for 2009–2011 and follow up was conducted from 2012 to 2016 through the cancer registry. Incidence rate ratios (IRRs) were computed for all sites and for the most frequent cancer sites. Results: among residents, 21,190 people had diabetes, 2282 of whom were taking insulin; 1689 cancers occurred, 180 among insulin users. The risk for all site was slightly higher in people with T2DM compared to people without DM (IRR 1.21, 95% CI 1.14–1.27), with no excess for T1DM (IRR 0.73, 95% CI 0.45–1.19). The excess in T2DM remained when comparing with diet-only treatment. In T2DM, excess incidence was observed for liver and pancreas and for NETs: 1.76 (95% CI 1.44–2.17) and 1.37 (95% CI 0.99–1.73), respectively. For bladder, there was an excess both in T1DM (IRR 3.00, 95% CI 1.12, 8.02) and in T2DM (IRR1.27, 95% CI 1.07–1.50). Conclusions: Insulin was associated with a 20% increase in cancer incidence. The risk was higher for liver, pancreatic, bladder and neuroendocrine tumours.

Monocarboxylate Transporters 1 and 4 and Prognosis in Small Bowel Neuroendocrine Tumors

Monocarboxylate transporters (MCTs) are cell membrane proteins transporting lactate, pyruvate, and ketone bodies across the plasma membrane. The prognostic role of MCTs in neuroendocrine tumors is unknown. We aimed to analyze MCT1 and MCT4 expression in small bowel neuroendocrine tumors (SB-NETs). The cohort included 109 SB-NETs and 61 SB-NET lymph node metastases from two Finnish hospitals. Tumor samples were immunohistochemically stained with MCT1 and MCT4 monoclonal antibodies. The staining intensity, percentage of positive cells, and stromal staining were assessed. MCT1 and MCT4 scores (0, 1 or 2) were composed based on the staining intensity and the percentage of positive cells. Survival analyses were performed with the Kaplan–Meier method and Cox regression, adjusted for confounders. The primary outcome was disease-specific survival (DSS). A high MCT4 intensity in SB-NETs was associated with better DSS when compared to low intensity (85.7 vs. 56.6%, p = 0.020). A high MCT4 percentage of positive cells resulted in better DSS when compared to a low percentage (77.4 vs. 49.1%, p = 0.059). MCT4 scores 0, 1, and 2 showed DSS of 52.8 vs. 58.8 vs. 100% (p = 0.025), respectively. After adjusting for confounders, the mortality hazard was lowest in the patients with a high MCT4 score. MCT1 showed no association with survival. According to our study, a high MCT4 expression is associated with an improved prognosis in SB-NETs.

Survival According to Therapy Regimen for Small Intestinal Neuroendocrine Tumors

Introduction: Scarce data exist for therapy regimens other than somatostatin analogues (SSA) and peptide receptor radiotherapy (PRRT) for siNET. We analyzed real world data for differences in survival according to therapy. Patients and methods: Analysis of 145 patients, diagnosed between 1993 and 2018 at a single institution, divided in treatment groups. Group (gr.) 0: no treatment (n = 10), gr 1: TACE and/or PRRT (n = 26), gr. 2: SSA (n = 32), gr. 3: SSA/PRRT (n = 8), gr. 4: chemotherapy (n = 8), gr. 5: not metastasized (at diagnosis), surgery only (n = 53), gr. 6 = metastasized (at diagnosis), surgery only (n = 10). Results: 45.5% female, median age 60 years (range, 27–84). A total of 125/145 patients with a resection of the primary tumor. For all patients, 1-year OS (%) was 93.8 (95%-CI: 90–98), 3-year OS = 84.3 (CI: 78–90) and 5-year OS = 77.5 (CI: 70–85). For analysis of survival according to therapy, only stage IV patients (baseline) that received treatment were included. Compared with reference gr. 2 (SSA only), HR for OS was 1.49 (p = 0.47) for gr. 1, 0.72 (p = 0.69) for gr. 3, 2.34 (p = 0.19) for gr. 4. The 5 y OS rate of patients whose primary tumor was resected (n = 125) was 73.1%, and without PTR was 33.3% (HR: 4.31; p = 0.003). Individual patients are represented in swimmer plots. Conclusions: For stage IV patients in this analysis (limited by low patient numbers in co. 3/4), multimodal treatment did not significantly improve survival over SSA treatment alone. A resection of primary tumor significantly improves survival.

Patterns of Use and Clinical Outcomes with Long-Acting Somatostatin Analogues for Neuroendocrine Tumors: A Nationwide French Retrospective Cohort Study in the Real-Life Setting

Introduction

Long-acting somatostatin analogues such as lanreotide autogel (LAN) and octreotide long-acting release (OCT) are recommended as first-line treatment for patients with neuroendocrine tumors (NETs). However, only few real-world studies have compared the two medications. This retrospective, observational cohort study used a French claims database to compare patterns of use with LAN vs. OCT in patients with NETs.

Methods

Data on LAN and OCT patterns of use were obtained retrospectively from the National System of Health Data (SNDS), a national French claims database. Patients 18 years of age or older who initiated treatment for NETs between 2009 and 2016, and who received at least six subsequent dispensings of first-line LAN or OCT during the first year of treatment, were included. A subgroup analysis was performed on patients with gastroenteropancreatic (GEP)-NETs.

Results

Patients receiving LAN (n = 2327) vs. OCT (n = 2090) had greater median treatment duration (31.8 months vs. 22.1 months, respectively; p < 0.0001; log-rank test) and were less likely to discontinue treatment; adjusted hazard ratio (HR) 0.74 (95% confidence interval [CI] 0.69–0.80). In year 1, a significantly lower percentage of patients receiving LAN vs. OCT switched treatments (10.4% vs. 22.2%, respectively; p < 0.0001), received an average monthly dose per trimester above recommended dose (3.0% vs. 7.3%, respectively; p < 0.0001), and used rescue medication (3.1% vs. 10.0%, respectively; p < 0.0001). Dispensing of pancreatic enzymes was significantly higher in patients receiving LAN than OCT (16.4% vs. 13.9%, respectively). In the subgroup of patients with GEP-NETs, those receiving LAN (n = 1478) vs. OCT (n = 1278) had greater treatment duration and less treatment discontinuation, switching, dosage above the recommended dose, and rescue medication use, but no significant difference in dispensing of pancreatic enzymes or time to second-line treatment.

Conclusion

These real-world data suggest potential clinical and economic advantages of LAN over OCT in the management of patients with NETs in the French population.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-022-02060-1.

Merkel cell carcinoma

Merkel cell carcinoma (MCC) is a rare neuroendocrine carcinoma. The cellular origin of MCC may include Merkel cell precursors. The incidence of MCC has increased significantly however trends may have been confounded by evolving diagnostic criteria. The two key aetiologies of MCC are ultraviolet radiation and Merkel cell polyoma virus (MCPyV). Both have unique mechanisms of carcinogenesis. MCC presents non-specifically as a rapidly growing, red-to-violet nodule on sun-exposed areas. Diagnostic accuracy has improved through immunohistochemical markers such as CK-20. Lymph nodes should be evaluated in MCC through examination and sentinel biopsy. USS, CT, MRI and CT-PET may be useful in staging. Management depends on tumour location, stage and comorbidities. MCPyV status may guide treatment strategy in the future. Treatment for the primary MCC is commonly wide local excision followed by radiotherapy, guided by anatomical constraints. There is uncertainty about surgical margins. Treatments for nodal disease have not been determined through trials. They include nodal dissection or radiotherapy for clinically or radiologically apparent disease, and adjuvant nodal irradiation for negative nodes, microscopic disease or following nodal dissection for definite disease. Patients with loco-regional advanced inoperable disease should be considered for combination therapy including chemotherapy, radiotherapy, surgery and immunotherapy. Systemic therapy for advanced disease includes immune checkpoint inhibitors targeting the PD-1/PD-L1 pathway. Avelumab can improve survival in metastatic MCC. Immunotherapy may result in longer disease control. Various other immunotherapeutic and molecular agents are undergoing trials. MCC continues to have a high mortality characterized by high recurrence and early metastases.

Immunotherapy of cancer tumors with inhibition of PD-1 membrane protein and its ligands interaction

The identification of the PD-1 receptor by Tasuku Honjo and CTLA-4 by James Ellison marked the beginning of the study of new regulatory pathways activating the immune response. The term “immune checkpoints” was introduced to denote the system of inhibitory mechanisms that include these proteins. The review presents the literature data on the molecular characteristics of the membrane protein PD-1 (programmed cell death 1 receptor) and its role in the regulation of immunity. We consider the PD-1 pathways used of by tumor cells to escape the immune response. The discovery of immune checkpoints made it possible to develop a new type of targeting therapy for cancer. The review presents the results of clinical trials of drugs that block the interaction between the PD-1 and its ligands in various types of cancer. These drugs include nivolumab, pembrolizumab, and avelumab. Studies of these drugs efficacy in patients with various types of cancer localization were conducted within the CheckMate, KEYNOTE and JAVELIN Solid Tumor programs, with some research being in progress. We analyze the results of studying the clinical efficacy of the drugs in patients with melanoma, lung cancer, renal cell cancer, colorectal cancer, classical Hodgkin’s lymphoma, Merkel carcinoma and stomach cancer. Both positive and inconclusive results in the treatment of patients are noted. These data made it possible to identify promising directions for the use of the drugs in certain localizations of the malignant process, as well as to determine the dose and time of their use to obtain an objective positive response to treatment.

Time from first tumor manifestation to diagnosis in patients with GEP-NET: Results from a large German tertiary referral center

Patients with neuroendocrine tumors (NET) often go through a long phase between onset of symptoms and initial diagnosis.Assessment of time to diagnosis and pre-clinical pathway in patients with gastroenteropancreatic NET (GEP-NET) with regard to metastases and symptoms.Retrospective analysis of patients with GEP-NET at a tertiary referral center from 1984 to 2019; inclusion criteria: Patients ≥18 years, diagnosis of GEP-NET; statistical analysis using non-parametrical methods.Four hundred eighty-six patients with 488 tumors were identified; median age at first diagnosis (478/486, 8 unknown) was 59 years; 52.9% male patients. Pancreatic NET: 143/488 tumors; 29.3%; small intestinal NET: 145/488 tumors, 29.7%. 128/303 patients (42.2%) showed NET specific and 122/486 (25%) patients other tumor-specific symptoms. 222/279 patients had distant metastases at initial diagnosis (187/222 liver metastases). 154/488 (31.6%) of GEP-NET were incidental findings. Median time from tumor manifestation (e.g., symptoms related to NET) to initial diagnosis across all entities was 19.5 (95% CI: 12-28) days. No significant difference in patients with or without distant metastases (median 73 vs 105 days, P = .42).A large proportion of GEP-NET are incidental findings and only about half of all patients are symptomatic at the time of diagnosis. We did not find a significant influence of the presence of metastases on time to diagnosis, which shows a large variability with a median of <30 days.

Merkel Cell Carcinoma

Merkel cell carcinoma (MCC) is a rare and extremely aggressive neuroendocrine carcinoma of the skin, with increasing incidence worldwide. This review intends to propose a comprehensive evaluation of MCC epidemiology, clinical features, pathogenetic mechanisms, diagnosis, and therapies. A section is dedicated to immunological aspects and another to the involvement of angiogenesis and angiogenic growth factors in MCC progression, proposing novel diagnostic and therapeutic approaches. Advanced MCC tumors have been treated with immune checkpoint inhibitors with effective results. Therefore, the state of art of this immunotherapy is also examined, reporting on the most recent clinical trials in the field. We conclude by underlining the achievements in the understanding of MCC pathology and indicating the present needs for effective diagnosis and therapeutic management of the disease.

Merkel Cell Carcinoma of Unknown Primary: Immunohistochemical and Molecular Analyses Reveal Distinct UV-Signature/MCPyV-Negative and High Immunogenicity/MCPyV-Positive Profiles

Simple Summary

Merkel cell carcinomas (MCCs) of unknown primary are defined as deep-seated tumors without an associated cutaneous tumor. Although the distinction has important clinical implications, it remains unclear whether these tumors represent primary tumors of lymph nodes or metastatic cutaneous primaries. We compared the immunohistochemical profiles of four groups of Merkel cell carcinomas (virus-positive and virus-negative unknown primary tumors and virus-positive and virus-negative cutaneous tumors) and performed molecular studies on the unknown primary tumors. Virus-positive and virus-negative Merkel cell carcinomas of unknown primary (MCC-UPs) exhibited an immunoprofile similar to virus-positive and virus-negative primary cutaneous MCCs, respectively. Similar to primary cutaneous Merkel cell carcinomas, virus-negative unknown primary tumors exhibited UV signatures and frequent high tumor mutational burdens, whereas few molecular alterations were noted in virus-positive tumors. Although additional studies are warranted for the virus-positive cases, our findings are supportive of a cutaneous metastatic origin for virus-negative Merkel cell carcinomas of unknown primary.

Abstract

Background: Merkel cell carcinomas of unknown primary (MCC-UPs) are defined as deep-seated tumors without an associated cutaneous tumor. Although the distinction has important clinical implications, it remains unclear whether these tumors represent primary tumors of lymph nodes or metastatic cutaneous primaries. Methods: We compared the immunohistochemical profiles of four groups of MCCs (Merkel cell polyomavirus (MCPyV)-positive UP, MCPyV-negative UP, MCPyV-positive known primary (KP), and MCPyV-negative KP) using B-cell and pre-B-cell markers, cell cycle regulating proteins, follicular stem cell markers, and immune markers, and performed next generation and Sanger sequencing. Results: Virus-positive and virus-negative MCC-UPs exhibited an immunoprofile similar to virus-positive and virus-negative primary cutaneous MCCs, respectively. MCC-UP tumors (both virus-positive and -negative) were immunogenic with similar or even higher tumoral PD-L1 expression and intratumoral CD8 and FoxP3 infiltrates in comparison to MCPyV-positive cutaneous tumors. In addition, similar to primary cutaneous MCCs, MCPyV-negative MCC-UPs exhibited UV signatures and frequent high tumor mutational burdens, whereas few molecular alterations were noted in MCPyV-positive MCC-UPs. Conclusions: Our results showed distinct UV-signatures in MCPyV-negative tumors and high immunogenicity in MCPyV-positive tumors. Although additional studies are warranted for the MCPyV-positive cases, our findings are supportive of a cutaneous metastatic origin for MCPyV-negative MCC-UP tumors.

The Role of Serum 5-HIAA as a Predictor of Progression and an Alternative to 24-h Urine 5-HIAA in Well-Differentiated Neuroendocrine Neoplasms

Simple Summary

5-hydroxyinoloacetic acid (5HIAA) is the breakdown product of serotonin and it is traditionally measured in 24-h urinary samples in patients with neuroendocrine neoplasms (NENs). 5HIAA measurement in patient serum has recently become available and has started replacing the traditional method in many centers, as it is more convenient and often preferred by patients. In this prospective, single center study, we aimed to investigate the clinical utility of serum 5HIAA for diagnostic purposes and disease surveillance in a cohort of patients with well-differentiated NENs. Our analysis confirmed an association between serum 5HIAA and the presence of liver metastases, as well as the extent of liver tumor involvement, demonstrating that the biomarker becomes positive in advanced disease stages. However, there was no evident association between a change in serum 5HIAA and change in disease status. Additionally, with respect to diagnostic purposes as compared to urinary 5HIAA testing, there was a substantial agreement between the two methods. In conclusion, serum 5HIAA performs well compared to urinary testing for diagnostic purposes but does not seem adequate as a solo biomarker of disease progression.

Abstract

Our aim was to investigate the clinical utility of serum 5HIAA for disease surveillance and diagnostic purposes in a cohort of patients with well-differentiated neuroendocrine neoplasms (WD-NENs). Forty-eight patients with WD-NENs and concurrent serum and urinary 5HIAA testing, as well as CT/MRI imaging, were included. Analysis of matching-pairs did not reveal any association between RECIST 1.1 responses and changes in serum 5HIAA levels (p = 0.673). In addition, no correlation was evident between RECIST 1.1 responses and >10%, >25% or >50% changes in serum 5HIAA levels (Fisher’s exact test p = 0.380, p > 0.999, and p > 0.999, respectively). The presence of liver metastases and extensive liver tumor involvement were associated with higher serum 5HIAA levels (p = 0.045 and p = 0.041, respectively). We also confirmed a strong linear correlation between the measurements of serum and urine 5HIAA (n = 24, r = 0.791, p < 0.0001). The concordance rate of serum and urinary 5HIAA positivity at standardized laboratory cut-offs was 75%. In patients with normal renal function tests, the concordance between the two methods was as high as 89%, and a sensitivity and specificity of 80% and 88.9%, respectively, was evident (Cohen’s kappa coefficient = 0.685). In conclusion, serum 5HIAA performs well compared to urinary testing for diagnostic purposes, mainly in advanced disease stages, and corresponds well to liver tumor burden. However, it is not adequate to predict tumor progression.

Cost-effectiveness of Lutetium [177Lu] oxodotreotide versus best supportive care with octreotide in patients with midgut neuroendocrine tumors in France

BACKGROUND AND AIMS

In France, there are approximately 2,400 new cases of neuroendocrine tumors (NETs) annually. Peptide receptor radionuclide therapy with ¹⁷⁷Lu-Dotatate plus long-acting repeatable [LAR] octreotide 30 mg has been shown to significantly improve progression-free survival and overall survival relative to high-dose octreotide LAR 60 mg in patients with unresectable or metastatic progressive midgut NETs. A long-term cost-effectiveness analysis was performed to assess whether ¹⁷⁷Lu-Dotatate is a cost-effective option versus octreotide 60 mg for patients with unresectable/metastatic progressive midgut NETs from the perspective of French healthcare payer.

METHODS

The analysis was performed using a three-state partitioned survival model. In the base case analysis ¹⁷⁷Lu-Dotatate plus octreotide LAR 30 mg was compared with high-dose octreotide LAR 60 mg in patients with midgut NETs. Survival data were obtained from the phase III NETTER-1 trial in patients with metastatic midgut NETs. Future costs and clinical outcomes were discounted at 4% per annum. One-way deterministic and probabilistic sensitivity analyses were performed.

RESULTS

In the base case analysis, for patients with midgut NETs, ¹⁷⁷Lu-Dotatate treatment improved quality-adjusted life expectancy by 1.21 quality-adjusted life years (QALYs) relative to octreotide LAR 60 mg and the lifetime treatment costs were EUR 50,784 higher with ¹⁷⁷Lu-Dotatate resulting in an incremental cost-effectiveness ratio (ICER) of EUR 42,106 per QALY gained versus octreotide LAR 60 mg. When compared with everolimus, ¹⁷⁷Lu-Dotatate was associated with an ICER of EUR 59,769 per QALY gained. Sensitivity analyses showed that the results were sensitive to methods used to extrapolate survival data.

CONCLUSIONS

For patients with advanced progressive midgut NETs ¹⁷⁷Lu-Dotatate is likely to be considered a cost-effective option versus octreotide 60 mg from the perspective of the French healthcare payer.

Evidence and Considerations on Treatment of Small Size Merkel Cell Head and Neck Carcinoma

Introduction  Merkel cell carcinoma (MCC) is a rare and aggressive neuroendocrine malignant cancer. It is an epidermal cancer common in the head and neck.

Objectives  Though there is limited number of cases described in the literature for the treatment difficult to obtain. Our purpose was to present the clinical course and treatment of four patients with MCC.

Methods  We conducted a retrospective analysis and obtained detailed clinical information for all 4 patients treated for MCC at the ENT Department of the SS Annunziata Hospital in Chieti, Italy, from 2013 through 2015.

Results  In our study, two patients presented with the tumor in a rare site (lower eyelid). All of the patients underwent surgical treatment: three patients had free excision margins and negative sentinel lymph nodes (SLNs) while 1 patient had free excision margins and positive SLNs. The latter patient underwent ipsilateral neck dissection. In another patient, the fluorodeoxyglucose positron emission topography (FDG PET)/computed tomography (CT) performed 6 months after the surgery has shown high metabolic activity in the left parotid gland, and the patient underwent total parotidectomy and a neck dissection.

Conclusion  Sentinel lymph node biopsy is a useful technique in small size MCCs of the head and neck. However, the parotid gland should be strictly controlled in patients with lower eyelid tumors.

Successful resection of a centrally located primary hepatic neuroendocrine tumor

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Primary hepatic neuroendocrine tumors (NETs) are extremely rare.

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A centrally located hepatic NET may present a challenging clinical situation.

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Surgical resection remains the treatment of choice and plays a potentially curative role.

Introduction

Primary neuroendocrine tumors (NETs) of the liver are rare tumors that are challenging to diagnose.

Presentation of case

A 41-year old woman presented with a four-month history of moderate abdominal pain in the right upper quadrant. A computed tomography scan of the abdomen revealed a large hypervascular liver lesion measuring 14 × 10 × 15 cm occupying segments IV and VIII and part of segment V of the liver. A liver biopsy revealed findings consistent with a well-differentiated NET. Transarterial chemoembolization was offered to the patient; however, the procedure was unsuccessful. Surgical management was therefore considered and resulted in a favorable outcome.

Discussion

Primary hepatic NETs are thought to originate from NET cells that may subsequently propagate to the intrahepatic biliary tree and become cancerous. These tumors are often missed during an initial evaluation due to a low clinical index of suspicion. In some cases, nonspecific symptoms such as abdominal pain and bloating may be an indication of early disease. No guidelines have been developed for the treatment of primary hepatic NETs; nevertheless, surgical resection remains the treatment of choice and plays a potentially curative role.

Conclusion

Surgical resection may be beneficial in the management of a primary NET of the liver even when the procedure appears to be challenging, such as in the case of a centrally located liver tumor.

Use of octreotide long acting repeatable (LAR) as second-line therapy in advanced neuroendocrine tumors in different clinical settings: an Italian Delphi survey

BACKGROUND

Somatostatin receptor ligands including octreotide LAR are first-line therapy in locally advanced or metastatic NETs that are nonresectable and well differentiated and are recommended as first-line therapy in functioning and in G1/low G2 nonfunctioning NETs. However, several questions remain that are not adequately addressed in current guidelines regarding its use in clinical scenarios in which the tumor progresses. These include use of nonconventional doses or schedules of octreotide LAR in tumors with hormonal symptoms or showing clinical-radiological progression, administration in combination with everolimus, peptide receptor radionuclide therapy, and chemotherapy, following first-line treatment with octreotide LAR.

METHODS

An expert panel was gathered to obtain consensus using Delphi methodology on a series of statements regarding further administration of octreotide LAR after its use in first-line therapy in these settings in patients who experience disease progression.

RESULTS

Consensus was reached for 8 of the 10 statements proposed in the above clinical scenarios; consensus was not achieved for two statements.

CONCLUSIONS

The present statements aim to fill current gaps in treatment guidelines by providing recommendations based on expert consensus in clinical settings in which patients progress following first-line therapy with octreotide LAR.

Pancreatic Neuroendocrine Neoplasms: Does Sex Matter?

Genetic and molecular disparities between men and women have a role in the differing incidence, pathophysiology, clinical signs, and treatment outcome of several cancers. Sex differences in cancer incidence are attributed to regulation at the genetic/molecular level and to sex hormones that in turn modulate gene expression in various cancers. Sex differences in the incidence of cancer, its aggressiveness, and the disease prognosis have been reported for several types of cancer but little is known for pancreatic neuroendocrine neoplasms (PNENs). The aim of this Opinion article is to provide an overview of sex differences in PNENs in terms of epidemiology, pathophysiology, treatment responses, prognosis, and survival. This overview might allow better tailoring of the management of PNENs.

Lymphoscintigraphy for Sentinel Node Mapping in Head and Neck Cancer

The aim of this comprehensive review is to describe and analyze the role of the sentinel node mapping in head and neck cancers. For this purpose, head and neck neoplasms have been categorized in cutaneous malignancies and neoplasms of the upper aerodigestive tract. A concise description of lymphatic drainage will be the "prelude" for each section, as well as the description of the injection techniques, when specific. Concisely, the attention has been focused on detection rate of the sentinel node by lymphoscintigraphy for each cancer, and for those patients in which the sentinel lymph node has been identified, true-positives rates, false-negative rates, and overall accuracy has been pointed out. Overall, in cutaneous neoplasms of the head and neck, the detection rate is higher than 90%, however the false-negative rate is still an issue, in particular in melanoma, inducing the need for newer developments. In fact, new tracers and techniques are already available, while prospective multicenter trials exploring the outcome impact are needed in the near future. For the upper aerodigestive tract and in particular oral cavity and oropharynx, sentinel lymph node identification by lymphoscintigraphy allows avoiding unnecessary neck dissection and/or node irradiation. Even in this case, the main limit remains the risk of false-negative rates. While, for patients affected by laryngeal and hypopharyngeal cancers the data seem very limited and, although the feasibility has been demonstrated, performances of this lymphoscintigraphy still need to be confirmed by multicenter studies.

Primary Merkel Cell Carcinoma: A Retrospective Analysis of 31 Cases in Poland

Introduction

Merkel cell carcinoma (MCC) is a rare, aggressive cutaneous neuroendocrine cancer that typically arises in sun-exposed areas of the skin, especially in the elderly. Significant advances have recently been made regarding skin cancers, but data on cases of MCC are rather limited as these patients are frequently grouped together with other non-melanoma skin cancers (NMSC). Here, we performed an analysis of the clinical profile of patients with MCC in Poland to identify major factors influencing the prognosis.

Methods

Approximately 13,000 pathology and medical records were examined to identify patients with MCC diagnosed between 2010 and 2019. The management and outcomes of patients with histologically confirmed MCC were retrospectively evaluated.

Results

Thirty-one patients diagnosed with MCC were identified. The tumor occurred predominantly in women (61.3%) and in the elderly (mean 75.6 years). Twenty-nine patients had locoregional MCC and two had metastatic MCC at the time of diagnosis. Patients in stage I disease had excellent prognosis. In stages II and III, respectively 22.2% and 50.0% of patients developed metastases. Among patients who received chemotherapy with cisplatin and etoposide, 17% achieved partial remission with progression-free survival (PFS) of 8.0 months, and a further 50% achieved stable disease with PFS of 4.0, 4.5, and 4.5 months respectively. In 6 (19.4%) patients MCC coexisted with chronic lymphocytic leukemia (CLL). In all six cases CLL preceded MCC development.

Conclusions

Female gender, tumor-free resection margins, and local disease were found to be independent prognostic factors in MCC progression. Patients with hematological malignancies, immunosuppression, and those with immune deficiencies should be closely followed up as they are predisposed to develop MCC.

Electronic supplementary material

The online version of this article (10.1007/s13555-020-00424-5) contains supplementary material, which is available to authorized users.

Merkel Cell Carcinoma - Current Controversies and Future Directions

Merkel cell carcinoma is a rare, aggressive neuroendocrine skin malignancy. Evidence for management comes from case series and single-arm trials. Optimal outcomes require assessment of the patient in a multidisciplinary team setting. Rapid diagnosis and staging are essential for locoregional control and may reduce metastasis. Sentinel lymph node biopsy (SLNB) adds prognostic information. FDG-positron emission tomography has high sensitivity and specificity and affects management in a quarter of cases. Surgical excision and radiotherapy provide good locoregional control even with positive margins. Wide surgical margins are needed if adjuvant radiotherapy is not used. It is uncertain whether adjuvant radiotherapy or elective surgery for uninvolved nodes or for patients selected by positive SLNB improves survival. Total doses of 50 Gy provide high levels of control for microscopic disease but at least 60 Gy should be given for macroscopic disease. Chemotherapy can be given safely with radiotherapy, but the benefit of adjuvant chemotherapy remains uncertain. Trials of adjuvant immune therapy are underway. Unresectable primaries might be controlled with radiotherapy alone or combination systemic therapy, radiotherapy and surgery. Metastatic disease often responds to chemotherapy, but the response duration can be short. Immunity is central to disease control. Immune checkpoint inhibitor treatment resulted in high response rates in chemotherapy-naive patients and lower rates in chemotherapy-refractory patients. Durable responses are observed.

Primary Neuroendocrine Neoplasms of the Breast: Case Series and Literature Review

Primary neuroendocrine carcinoma of the breast (NECB) as defined by the World Health Organization (WHO) in 2012 is a rare, but possibly under-diagnosed entity. It is heterogeneous as it entails a wide spectrum of diseases comprising both well-differentiated neuroendocrine tumors of the breast as well as highly aggressive small cell carcinomas. Retrospective screening of hospital charts of 612 patients (2008–2019) from our specialized outpatient unit for neuroendocrine neoplasia revealed five patients diagnosed with NECB. Given the low prevalence of these malignancies, correct diagnosis remains a challenge that requires an interdisciplinary approach. Specifically, NECB may be misclassified as carcinoma of the breast with neuroendocrine differentiation, carcinomas of the breast of no special type/invasive ductal carcinoma, or a metastasis to the breast. Therefore, this study presents multifaceted characteristics as well as the clinical course of these patients and discusses the five cases from our institution in the context of available literature.

Landscape of current and future therapies of Merkel cell carcinoma

Merkel cell carcinoma is rare and aggressive skin cancer, which occurrence is linked to exposure to ultraviolet light and the Merkel-cell polyomavirus. In recent years, significant progress in understanding the mechanism of Merkel cell carcinoma pathogenesis has been observed. This neoplasm often expresses PD-L1, and MCPyV-specific T cells can express PD-1 thus PD-1/PD-L1 checkpoint therapies seem to be remarkably interesting treatment options. Many clinical trials are currently being conducted to confirm their effectiveness and safety for this group of patients. However, only about half of advanced Merkel cell carcinoma patients could achieve remission or disease stabilization through PD-1/PD-L1 checkpoint therapies thus innovative treatments are still needed. In this article, we have presented current and future directions in the development of Merkel cell carcinoma therapy.

Elderly Patients with Metastatic Neuroendocrine Tumors Are Undertreated and Have Shorter Survival: The LyREMeNET Study

INTRODUCTION

The incidence of neuroendocrine tumors (NETs) is rising, especially in elderly patients. The elderly cancer population presents considerable challenges, yet little is known about the characteristics, treatment patterns, and outcomes of metastatic NET (mNET) patients.

METHODS

The Lyon Real-life Evidence in Metastatic NeuroEndocrine Tumors study (LyREMeNET, NCT03863106) included consecutive mNET patients, diagnosed between January 1990 and December 2017. The exclusion criteria were nonmetastatic NET, poorly differentiated neuroendocrine carcinoma, and mixed neuroendocrine-nonneuroendocrine neoplasms. We aimed to compare patients ≥70 years old to patients <70 years old.

RESULTS

A total of 866 patients were included, 198 (23%) were ≥70 years old. There was no significant difference in characteristics except that elderly patients had synchronous metastasis more frequently. Elderly patients received significantly fewer treatments (median of 2.0 vs. 3.0 lines, respectively, p < 0.0001), were significantly less frequently treated by chemotherapy (32 vs. 54%), targeted therapy (16 vs. 30%), peptide receptor radionuclide therapy (5 vs. 16%), and they underwent significantly less frequently locoregional intervention. Median overall survival was significantly shorter in elderly patients (5.2 vs. 9.6 years). The most frequent cause of death was related to disease progression (71%). Multivariate analysis found that, after adjustment for tumor location, tumor grade, and number of metastatic sites, age remained significantly associated with overall survival (HR 1.66, 95% CI 1.26-2.18), indicating a poorer survival in patients ≥70 years old in comparison with younger patients (p = 0.0003).

CONCLUSION

Patients ≥70 years old have a worse survival, die frequently from their disease, and are undertreated compared to younger patients.

Recent Survival Trends in High-Grade Neuroendocrine Neoplasms and Lung Cancer

BACKGROUND

Poorly differentiated neuroendocrine neoplasms (pdNEN) are a rare cancer entity, treatment of which is to a great part informed by studies on the much more common small-cell lung cancer (SCLC).

OBJECTIVE

To reveal and compare recent survival trends for pdNEN and SCLC in an authorative, population-based database.

METHODS

Using the Surveillance, Epidemiology, and End Results 18 database, 3,482 digestive tract pdNEN and 30,383 SCLC diagnosed from 2000 through 2015 were analyzed in detail.

RESULTS

Whereas changes in one- and 2-year relative survival in pdNEN were small, improvements in median survival appeared consistent and relevant. For example, median survival (95% CI) for distant disease pdNEN diagnosed in 2000-2004, 2005-2009, and 2010-2015 was 4.6 (3.8-5.4), 5.6 (4.5-6.7), and 6.4 (5.4-7.5) months. Changes in SCLC survival during the study period overall were even more limited, which - in the case of distant disease - meant that survival disadvantages of patients with pdNEN as compared to SCLC disappeared during the study period. Unfortunately, relevant improvements in year-wise conditional survival after the first year since diagnosis essentially were restricted to localized pdNEN and localized SCLC.

CONCLUSIONS

Our results should stipulate further research, in particular, of the pdNEN-SCLC relationship. They will also be helpful in patient care and communication, providing the first conditional survival details in this context, a highly patient-relevant outcome.

Exploring the current status of neuroendocrine tumours: a population-based analysis of epidemiology, management and use of resources

Background

Neuroendocrine tumours (NETs) are rare malignancies characterised by its capacity to synthesise and secrete monoamines, due to its neuroendocrine origin. Its varied locations and symptoms have traditionally been responsible for extended delays in their diagnosis. The interest of this study was to characterise the patient population diagnosed with NETs in Spain and to revise how the disease is managed, together with the hospitalisation costs of these patients.

Methods

The database included records of all patients diagnosed with a NET between 2010 and 2015. Admission records were used to evaluate hospitalisation, disease management data and costs, and single-patient files were used to characterise the population.

Results

Nine Thousand One Hundred Twenty patients were diagnosed with a neuroendocrine tumour between 2010 and 2015, with a 2 fold increase in the diagnosis rate over the study period. 42.25% of the patients were females, while 57.75% were males, and mean diagnosis age was 62.58 years (SD = 14.65). Considering all the registered neuroendocrine neoplasms, 46.86% of the patients had malignant well-differentiated NETs, 32.02% had a malignant poorly differentiated neuroendocrine carcinoma and 42.93% of patients developed metastatic NETs. In addition, 18.59% of patients were diagnosed with benign well-differentiated NETs. The most common tumour sites were the bronchus, lung and other sites, including pancreatic tumours; metastasis was found in the liver and distant lymph nodes. Pancreatic resection was the most common surgical procedure utilised in these patients, summing 19% of total expenses, the injection of an unspecified therapeutic substance (including targeted therapies) was registered in 11.40% of admissions, while chemotherapy was registered in only 6.85% of admissions. The annual healthcare cost of NETs was €15,373,961, corresponding to €9092 per patient.

Conclusions

The implementation of standard diagnosis procedures should be prioritised, with a focus on the pancreas and lung, and taking into account that 42.93% of the patients develop a metastatic tumour. The presence of comorbidities and multimorbidities should be considered in order to develop more efficient disease management protocols.

Merkel cell polyomavirus is implicated in a subset of Merkel cell carcinomas, in the Indian subcontinent

Merkel cell carcinoma is a rare, lethal cancer histopathologically composed of cells showing similarity with mechanoreceptor Merkel cells. Merkel cell tumors manifest in two distinct forms. While a virus called Merkel cell polyomavirus is involved in the pathogenesis of one form of Merkel tumors, the other is driven by ultraviolet (UV)-linked mutations. In this study we investigated 18 cases, from the Indian population, of Merkel cell carcinoma for immunohistochemical (IHC) expression of Merkel cell polyomavirus (MCV) T antigen, including 12 cases tested by PCR, to identify viral etiopathology. We tested the tumors with two sensitive antibodies (CM2B4 and Ab3), targeting the viral large T antigen protein and with PCR primers targeting the N terminus of T antigen. Overall, we observed 38.8% (7/18) tumors displaying positive IHC expression of Merkel cell polyomavirus T antigen and 25% (3/12) tumors showing positive results, by both, immunohistochemistry and PCR. This constitutes the first report from India showing implication of MCV in Merkel cell carcinomas. Moreover, this is one of the larger series of Merkel cell carcinomas, tested for MCV, by both immunohistochemistry and PCR, in this part of the world. These results further indicate that a slightly more number of such cases in India are likely to be caused by UV-linked damage, as opposed to Merkel cell polyomavirus mediated tumorigenesis, which is definitely implicated in a subset of cases.

Parallel Signaling through IRE1α and PERK Regulates Pancreatic Neuroendocrine Tumor Growth and Survival

Master regulators of the unfolded protein response (UPR), IRE1α and PERK, promote adaptation or apoptosis depending on the level of endoplasmic reticulum (ER) stress. Although the UPR is activated in many cancers, its effects on tumor growth remain unclear. Derived from endocrine cells, pancreatic neuroendocrine tumors (PanNET) universally hypersecrete one or more peptide hormones, likely sensitizing these cells to high ER protein-folding stress. To assess whether targeting the UPR is a viable therapeutic strategy, we analyzed human PanNET samples and found evidence of elevated ER stress and UPR activation. Genetic and pharmacologic modulation of IRE1α and PERK in cultured cells, xenograft, and spontaneous genetic (RIP-Tag2) mouse models of PanNETs revealed that UPR signaling was optimized for adaptation and that inhibiting either IRE1α or PERK led to hyperactivation and apoptotic signaling through the reciprocal arm, thereby halting tumor growth and survival. These results provide a strong rationale for therapeutically targeting the UPR in PanNETs and other cancers with elevated ER stress. SIGNIFICANCE: The UPR is upregulated in pancreatic neuroendocrine tumors and its inhibition significantly reduces tumor growth in preclinical models, providing strong rationale for targeting the UPR in these cancers.

Treatment of Advanced Merkel Cell Carcinoma: Current Therapeutic Options and Novel Immunotherapy Approaches

Advanced Merkel cell carcinoma (MCC) is a very aggressive, rare neuroendocrine tumor of the skin with a high frequency of locoregional recurrence and metastasis, and a high mortality rate. Surgical resection, sentinel lymph node biopsy, and radiotherapy represent the gold standard of treatment in patients with localized disease, while chemotherapy has a significant role in the treatment of advanced disease. However, no definitive evidence on the survival impact of radiotherapy in the advanced stages has been provided to date, and response to chemotherapy remains brief in the majority of cases, indicating an urgent need for alternative approaches. Biological and genome sequencing studies have implicated multiple molecular pathways in MCC, thus leading to the development of new agents that target angiogenic factors, anti-apoptosis molecules, poly-ADP ribose polymerase, intracellular signal proteins such as the PI3K/AKT/mTOR pathway, and peptide receptors such as somatostatin receptors. More recently, immunotherapy agents such as avelumab, pembrolizumab, and nivolumab, which act by blocking the programmed cell-death (PD)-1/PD-L1 immune checkpoint, have shown promising results, especially in the advanced setting, and should now be considered standard of care for metastatic MCC. Current research is focusing on developing new immunotherapeutic strategies, identifying predictive biomarker to aid in the selection of patients responsive to immunotherapy, and defining combination approaches to increase efficacy in refractory patients.

The Genomic Landscape of Merkel Cell Carcinoma and Clinicogenomic Biomarkers of Response to Immune Checkpoint Inhibitor Therapy

PURPOSE

Merkel cell carcinoma (MCC) is a rare, aggressive cutaneous malignancy, which has demonstrated sensitivity to immune checkpoint inhibitor therapy. Here, we perform the largest genomics study in MCC to date to characterize the molecular landscape and evaluate for clinical and molecular correlates to immune checkpoint inhibitor response.

EXPERIMENTAL DESIGN

Comprehensive molecular profiling was performed on 317 tumors from patients with MCC, including the evaluation of oncogenic mutations, tumor mutational burden (TMB), mutational signatures, and the Merkel cell polyomavirus (MCPyV). For a subset of 57 patients, a retrospective analysis was conducted to evaluate for clinical and molecular correlates to immune checkpoint inhibitor response and disease survival.

RESULTS

Genomic analyses revealed a bimodal distribution in TMB, with 2 molecularly distinct subgroups. Ninety-four percent (n = 110) of TMB-high specimens exhibited an ultraviolet light (UV) mutational signature. MCPyV genomic DNA sequences were not identified in any TMB-high cases (0/117), but were in 63% (110/175) of TMB-low cases. For 36 evaluable patients treated with checkpoint inhibitors, the overall response rate was 44% and response correlated with survival at time of review (100% vs. 20%, P < 0.001). Response rate was 50% in TMB-high/UV-driven and 41% in TMB-low/MCPyV-positive tumors (P = 0.63). Response rate was significantly correlated with line of therapy: 75% in first-line, 39% in second-line, and 18% in third-line or beyond (P = 0.0066). PD-1, but not PD-L1, expression was associated with immunotherapy response (77% vs. 21%, P = 0.00598, for PD-1 positive and negative, respectively).

CONCLUSIONS

We provide a comprehensive genomic landscape of MCC and demonstrate clinicogenomic associates of immunotherapy response.

S2k guidelines for Merkel cell carcinoma (MCC, neuroendocrine carcinoma of the skin) - update 2018

Merkel cell carcinoma (MCC, ICD-O M8247 / 3) is a rare malignant primary skin tumor with epithelial and neuroendocrine differentiation. The neoplastic cells share many morphological, immunohistochemical and ultrastructural characteristics with Merkel cells of the skin. The diagnosis of MCC is rarely made on clinical grounds. Histological and immunohistochemical studies are usually required to confirm the clinical suspicion. Given the frequent occurrence of occult lymph node metastasis, sentinel lymph node biopsy should be performed once distant metastasis has been ruled out by cross-sectional imaging. Primary tumors without evidence of organ metastases are treated with complete surgical excision with appropriate surgical margins. Radiation therapy should be considered at all stages of the disease. For advanced MCC that is no longer amenable to curative treatment by surgery or radiation therapy, there is currently no established systemic therapy for which an improvement in recurrence-free survival or overall survival has been demonstrated in a prospective randomized trial. However, immunotherapy using PD-1/PD-L1 blockade seems to be superior to chemotherapy. Various factors warrant that further diagnostic and therapeutic interventions be determined by an interdisciplinary tumor board. These factors include the tumor's aggressiveness, the frequent indication for sentinel lymph node biopsy along with the frequent occurrence in the head and neck region, the potential indication for adjuvant radiation therapy as well as the complexity of the required diagnostic workup.

Merkel Cell Polyoma Viral Load and Intratumoral CD8+ Lymphocyte Infiltration Predict Overall Survival in Patients With Merkel Cell Carcinoma

Introduction: Merkel cell carcinoma (MCC) is linked to the presence of clonally integrated Merkel cell polyomavirus (MCPyV) in up to 80% of the cases. The aim of the study was to determine the prognostic value of baseline MCPyV viral load and lymphocytic infiltration.

Methods: MCPyV DNA prevalence, integration status and viral load were determined by specific quantitative real-time PCR in surgical specimens obtained from 49 patients with MCC treated with (n = 22, 45%) or without postoperative radiotherapy (RT). CD8+ tumor infiltrating lymphocytes (TILs) and programmed death ligand 1 (PD-L1) status were assessed using immunohistochemistry. MCPyV characteristics and immune marker expression were correlated with clinicopathological factors and overall survival (OS).

Results: Median age at diagnosis was 74 (range, 42–100); 51% of the patients were female. One-, three, and five-year OS rates were 83.8, 58.6, and 47.1%, respectively. A positive MCPyV status was associated with female gender (p = 0.042). Tumor localization (head/arms vs. trunk) positively correlated with PD-L1 status (p = 0.011) and combined CD8/PD-L1 expression (p = 0.038). Overall CD8+ infiltration was inversely associated with N-stage (p = 0.048). Stromal TILs correlated significantly with both PD-L1 expression (p = 0.010) and N-stage (p = 0.037). A high viral load (>median) was significantly associated with worse OS (p = 0.029) and high intratumoral CD8+ infiltration with improved OS for the entire cohort (p = 0.045).

Conclusion: These data provide important insight on the role of MCPy DNA viral load and TILs in the context of PD-L1 in patients with Merkel cell carcinoma. Future clinical studies should aim to explore the effect of PD-1/PD-L1 immune-checkpoint inhibitors in combination with existing radiotherapy approaches.