Everolimus, lutetium-177 DOTATATE and sunitinib for advanced, unresectable or metastatic neuroendocrine tumours with disease progression: a systematic review and cost-effectiveness analysis

BACKGROUND

Neuroendocrine tumours (NETs) are a group of heterogeneous cancers that develop in cells in the diffuse neuroendocrine system.

OBJECTIVES

To estimate the clinical effectiveness of three interventions [everolimus (Afinitor^®; Novartis International AG, Basel, Switzerland), lutetium-177 DOTATATE (177Lu-DOTATATE) (Lutathera^®; Imaging Equipment Ltd, Radstock, UK) and sunitinib (Sutent^®; Pfizer Inc., New York, NY, USA)] for treating unresectable or metastatic NETs with disease progression and establish the cost-effectiveness of these interventions.

DATA SOURCES

The following databases were searched from inception to May 2016: MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, MEDLINE Daily, Epub Ahead of Print, EMBASE, Cochrane Central Register of Controlled Trials and Web of Science.

REVIEW METHODS

We systematically reviewed the clinical effectiveness and cost-effectiveness literature on everolimus, 177Lu-DOTATATE and sunitinib for treating advanced, unresectable or metastatic progressive NETs. The following NET locations were considered separately: pancreas, gastrointestinal (GI) tract and lung, and GI tract (midgut only). We wrote a survival partition cohort-based economic evaluation in Microsoft Excel^® 2013 (Microsoft Corporation, Redmond, WA, USA) from the UK NHS and Personal Social Services perspective. This comprised three health states: (1) progression-free survival (PFS), (2) progressed disease and (3) death.

RESULTS

Three randomised controlled trials (RCTs), RADIANT-3 [RAD001 in Advanced Neuroendocrine Tumors, Third Trial; pancreatic NETs (pNETs): everolimus vs. best supportive care (BSC)], A6181111 (pNETs: sunitinib vs. BSC) and RADIANT-4 (RAD001 in Advanced Neuroendocrine Tumors, Fourth Trial; GI and lung NETs: everolimus vs. BSC), met the inclusion criteria for the clinical effectiveness systematic review. The risk of bias was low. Although the NETTER-1 (Neuroendocrine Tumors Therapy) RCT, of 177Lu-DOTATATE plus 30 mg of octreotide (Sandostatin^®, Novartis) compared with 60 mg of octreotide, was excluded from the review, we nonetheless present the results of this trial, as it informs our estimate of the cost-effectiveness of 177Lu-DOTATATE. The pNETs trials consistently found that the interventions improved PFS and overall survival (OS) compared with BSC. Our indirect comparison found no significant difference in PFS between everolimus and sunitinib. Estimates of OS gain were confounded because of high rates of treatment switching. After adjustment, our indirect comparison suggested a lower, but non-significant, hazard of death for sunitinib compared with everolimus. In GI and lung NETs, everolimus significantly improved PFS compared with BSC and showed a non-significant trend towards improved OS compared with BSC. Adverse events were more commonly reported following treatment with targeted interventions than after treatment with BSC. In the base case for pNETs, assuming list prices, we estimated incremental cost-effectiveness ratios (ICERs) for everolimus compared with BSC of £45,493 per quality-adjusted life-year (QALY) and for sunitinib compared with BSC of £20,717 per QALY. These ICERs increased substantially without the adjustment for treatment switching. For GI and lung NETs, we estimated an ICER for everolimus compared with BSC of £44,557 per QALY. For GI (midgut) NETs, the ICERs were £199,233 per QALY for everolimus compared with BSC and £62,158 per QALY for a scenario analysis comparing 177Lu-DOTATATE with BSC. We judge that no treatment meets the National Institute for Health and Care Excellence's (NICE) end-of-life criteria, although we cannot rule out that sunitinib in the A6181111 trial does.

LIMITATIONS

A RCT with included comparators was not identified for 177Lu-DOTATATE. The indirect treatment comparison that our economic analysis was based on was of a simple Bucher type, unadjusted for any differences in the baseline characteristics across the two trials.

CONCLUSIONS

Given NICE's current stated range of £20,000-30,000 per QALY for the cost-effectiveness threshold, based on list prices, only sunitinib might be considered good value for money in England and Wales.

FUTURE WORK

Further analysis of individual patient data from RADIANT-3 would allow assessment of the robustness of our findings. The data were not made available to us by the company sponsoring the trial.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42016041303.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Novel medical therapies of recurrent and metastatic gastroenteropancreatic neuroendocrine tumors

Neuroendocrine tumors (NETs) of the gastrointestinal tract and pancreas are slow-growing but commonly advanced malignancies with increasing incidence and prevalence. While locoregional disease can be effectively managed with resection, treatment of recurrent, progressive or metastatic disease has until recently been limited to palliative embolization and cytoreducitve surgery, with cytotoxic chemotherapeutic agents being the last resort. However, novel molecular targeted therapies inhibiting malignant cell proliferation and neoangiogenesis, as well as new cytotoxic chemotherapy drugs and somatostatin analogues, are all being investigated for their potential use in advanced neuroendocrine tumors. Long-acting release forms of octreotide have been shown to not only improve symptoms in carcinoid syndrome but to also delay progression of gastrointestinal NETs. On the other hand, phase III trials have demonstrated everolimus (with octreotide) and sunitinib to increase progression-free survival in pancreatic NETs. Use of bevacizumab has also shown promise in a phase II study, and results of an ongoing phase III trial comparing it to interferon are eagerly expected. Use of radiolabeled somatostatin analogues is still under investigation, though several phase II studies are encouraging. New cytotoxic agents, most notably temozolomide and capecitabine, are already in use, but their relative effectiveness compared to streptozocin in pancreatic NETs is yet to be determined.

Neuroendocrine tumors: a population-based study of incidence and survival in Girona Province, 1994-2004

BACKGROUND

Neuroendocrine tumors (NETs) belong to a rare and heterogeneous group of neoplasms with a wide range of aggressiveness. Little information is available about incidence and mortality of NETs in the World population. The objective of this study was to report the incidence and survival of these tumors in Girona Province.

METHODS

We include all ICD-O3 codes that codified a NET, period 1994-2004. Data from malignant NETs came directly from the Girona Cancer Registry, and data from benign or with uncertain behavior NETs directly from the Anatomic-Pathological Laboratories.

RESULTS

We identified 698 NETs, the most frequent were those aroused in the bronco-pulmonary system (65.75%), followed by the gastro-entero-pancreatics (GEP) (12.75%). Small cell lung carcinomas were the most frequent NETs of the bronco-pulmonary system (92.59%), with an age-standardized incidence rate (ASRw, world population standard) of 4.29/100,000 person-years. Carcinoid lung tumors had an ASRw of 0.32/100,000 person-years and a 5-year relative survival (RS) of 77%. The ASRw of GEP NETs was 1.07/100,000 person-years, and the 5-year RS was 95%. The 5-year RS of pancreas was 43%. Thyroid NETs had an ASRw of 0.17/100,000 person-years, and a 5-year RS of 75%. Pheocromocytomas had an ASRw of 0.47/100,000 person-years and a 5-year RS of 85%. Merkel cell carcinomas had an ASRw of 0.11/100,000 person-years, with a 5-year RS of 50%.

CONCLUSION

To our knowledge, this is the first population-based study reporting incidence of NETs in Spain. Our data was consistent with other European reports. By providing the incidence and survival of NETs in Girona Province, this study contributes to a better understanding of these rare tumors.

SEOM clinical guidelines for the diagnosis and treatment of gastroenteropancreatic neuroendocrine tumours (GEP NETS)

Gastroenteropancreatic neuroendocrine tumours (GEP NETs) represent a heterogenous family of tumours with growing incidence and challenging clinical management. Unlike other solid tumours, they have the ability to secrete different peptides and neuramines that cause distinct clinical syndromes. However, many are clinically silent until advanced disease. This guideline aims to provide practical recommendations for the diagnosis and treatment of GEP NETs. Most recent histological and staging classifications, as well as available therapeutic approaches, such as surgery, locoregional therapy, peptide receptor radionuclide therapy (PRRT) and hormonal or systemic therapy, are discussed in this manuscript, including some recent relevant achievements with novel targeted agents. Clinical presentation (with or without hormonal syndrome), histological tumour features (including proliferation index (Ki-67) and the presence or not of somatostatin receptors), tumour stage, and location of primary tumour and distant metastasis are all key issues that shall be taken into consideration to properly design and integrate the most adequate therapeutic strategy.

Future perspectives on neuroendocrine tumors

In the last 30 years the incidence and prevalence of gastroenteropancreatic neuroendocrine tumors (GEP-NETs) has increased substantially. This could be partly due to improvements in diagnostic imaging, which lead to the incidental diagnosis of asymptomatic cases. However, despite these improvements, patients typically experience long delays before they are diagnosed. In this review, we discuss both the limitations and advances in our understanding of the pathogenesis, molecular and cellular biology, diagnosis, classification, staging, and treatment of GEP-NETs in order to identify which factors could be contributing to the delay in diagnosis and timely treatment of these patients. Within this context, the results from the most relevant clinical trials the available targeted therapies for the treatment of GEP-NETs, such as the "RAD001 in Advanced Neuroendocrine Tumors," will be discussed.

Pancreatic endocrine tumors

Pancreatic endocrine tumors have been steadily growing in incidence and prevalence during the last two decades, showing an incidence of 4-5/1,000,000 population. They represent a heterogeneous group with very varying tumor biology and prognosis. About half of the patients present clinical symptoms and syndromes related to substances released from the tumors (Zollinger-Ellison syndrome, insulinoma, glucagonoma, etc) and the other half are so-called nonfunctioning tumors mainly presenting with symptoms such as obstruction, jaundice, bleeding, and abdominal mass. Ten percent to 15% of the pancreatic endocrine tumors are part of an inherited syndrome such as multiple endocrine neoplasia type 1 (MEN-1), von Hippel-Lindau (VHL), neurofibromatosis, or tuberousclerosis. The diagnosis is based on histopathology demonstrating neuroendocrine features such as positive staining for chromogranin A and specific hormones such as gastrin, proinsulin, and glucagon. Moreover, the biochemical diagnosis includes measurement of chromogranins A and B or specific hormones such as gastrin, insulin, glucagon, and vasoactive intestinal polypeptide (VIP) in the circulation. In addition to standard localization procedures, radiology (computed tomography [CT] scan, magnetic resonance imaging [MRI], ultrasound [US]), somatostatin receptor scintigraphy, and most recently positron emission tomography with specific isotopes such as (11)C-5 hydroxytryptamin ((11)C-5-HTP), fluorodopa and (68)Ga-1,4,7,10-tetra-azacyclododecane-N,N',N″,N‴-tetra-acetic acid (DOTA)-octreotate are performed. Surgery is still one of the cornerstones in the management of pancreatic endocrine tumors, but curative surgery is rarely obtained in most cases because of metastatic disease. Debulking and other cytoreductive procedures might facilitate systemic treatment. Cytotoxic drugs, biological agents, such as somatostatin analogs, alpha interferons, mammalian target of rapamycin (mTOR) inhibitors and tyrosine kinase inhibitors are routinely used. Tumor-targeted radioactive treatment is available in many centres in Europe and is effective in patients with tumors that express high content of somatostatin receptors type 2 and 5. In the future, treatment will be based on tumor biology and molecular genetics with the aim of so-called personalized medicine.

Laparoscopic radiofrequency thermal ablation of neuroendocrine hepatic metastases: long-term follow-up

BACKGROUND

Since our first report 13 years ago, laparoscopic radiofrequency ablation has been incorporated into the treatment algorithm of patients with neuroendocrine liver metastases. The aim of this study is to report long-term oncologic results.

METHODS

Eighty-nine patients with neuroendocrine hepatic metastases underwent 119 laparoscopic radiofrequency ablation sessions within 13 years. Data were obtained from a prospective, Institutional Review Board approved database. Univariate Kaplan Meier and multivariate Cox proportional hazards model were used for statistical analyses. Data are expressed as mean ± standard error of the mean.

RESULTS

Thirty-five women and 54 men with a mean age of 56 ± 1.4 years were included in this study. Tumor types included were carcinoid (n = 55), pancreatic islet cell (n = 23), and medullary thyroid cancer (n = 11). Mean tumor size was 3.6 ± 0.2 and the number of lesions was 6 ± 1. Perioperative morbidity was 6%, and 30-day mortality was 1%. Symptom relief was achieved in 97% of patients after radiofrequency ablation. Median follow-up was 30 ± 3 months. Twenty-two percent of patients developed local liver recurrence, 63% developed new liver lesions, and 59% developed extrahepatic disease in follow-up. Repeat radiofrequency ablation (27%) and chemoembolization (7%) were used to achieve additional local tumor control in follow up. Median disease-free survival was 1.3 years and the overall survival was 6 years after radiofrequency ablation. Liver tumor volume, symptoms, and extrahepatic disease were independent predictors of survival.

CONCLUSION

To our knowledge, this is the largest prospective experience with radiofrequency ablation of neuroendocrine liver metastases. Effective symptom palliation and long-term local tumor control are possible in these patients with minimal morbidity.

Novel molecular therapies in hepatocellular carcinoma

The approval of sorafenib as the standard of care (SOC) for advanced hepatocellular carcinoma (HCC) fostered interest to further evaluate several other targeted therapies and extend the positioning of sorafenib alone and in combination with other drugs and local therapies at earlier stages and in an adjuvant setting. This review highlights current research using targeted therapies in HCC. Information for this review was compiled by searching PubMed and MEDLINE databases for articles published until September 2010. Several small molecules and humanized antibodies with anti-angiogenic and antiproliferative properties are currently being investigated in preclinical and/or clinical trials. Results are awaited from these clinical trials and offer promise for extending the current treatment options in HCC. Currently published data suggest that substantial progress may be achieved in the treatment of patients with HCC in the next 10 years.

New pharmacologic therapies for gastroenteropancreatic neuroendocrine tumors

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