A multigenomic liquid biopsy biomarker for neuroendocrine tumor disease outperforms CgA and has surgical and clinical utility.

BACKGROUND: Biomarkers are key tools in cancer management. In neuroendocrine tumors (NETs), Chromogranin A (CgA) was considered acceptable as a biomarker. We compared the clinical efficacy of a multigenomic blood biomarker (NETest) to CgA over a 5-year period. PATIENTS AND METHODS: An observational, prospective, cross-sectional, multicenter, multinational, comparative cohort assessment. Cohort 1: NETest evaluation in NETs (n = 1684) and cancers, benign diseases, controls (n = 731). Cohort 2: (n = 1270): matched analysis of NETest/CgA in a sub-cohort of NETs (n = 922) versus other diseases and controls (n = 348). Disease status was assessed by response evaluation criteria in solid tumors (RECIST). NETest measurement: qPCR [upper limit of normal (ULN: 20)], CgA (EuroDiagnostica, ULN: 108 ng/ml). STATISTICS: Mann-Whitney U-test, AUROC, chi-square and McNemar' test. RESULTS: Cohort 1: NETest diagnostic accuracy was 91% (P < 0.0001) and identified pheochromocytomas (98%), small intestine (94%), pancreas (91%), lung (88%), gastric (80%) and appendix (79%). NETest reflected grading: G1: 40 ± 1, G2 (50 ± 1) and G3 (52 ± 1). Locoregional disease levels were lower (38 ± 1) than metastatic (52 ± 1, P < 0.0001). NETest accurately stratified RECIST-assessed disease extent: no disease (21 ± 1), stable (43 ± 2), progressive (62 ± 2) (P < 0.0001). NETest concordance with imaging (CT/MRI/68Ga-SSA-PET) 91%. Presurgery, all NETs (n = 153) were positive (100%). After palliative R1/R2 surgery (n = 51) all (100%) remained elevated. After curative R0-surgery (n = 102), NETest levels were normal in 81 (70%) with no recurrence at 2 years. In the 31 (30%) with elevated levels, 25 (81%) recurred within 2 years. Cohort #2: NETest diagnostic accuracy was 87% and CgA 54% (P < 0.0001). NETest was more accurate than CgA for grading (chi-square = 7.7, OR = 18.5) and metastatic identification (chi-square = 180, OR = 8.4). NETest identified progressive disease (95%) versus CgA (57%, P < 0.0001). Imaging concordance for NETest was 91% versus CgA (46%) (P < 0.0001). Recurrence prediction after surgery was NETest-positive in >94% versus CgA 11%. CONCLUSION: NETest accurately diagnoses NETs and is an effective surrogate marker for imaging, grade, metastases and disease status compared to CgA. A multigenomic liquid biopsy is an accurate biomarker of NET disease.

Efficacy of everolimus plus octreotide LAR in patients with advanced neuroendocrine tumor and carcinoid syndrome: final overall survival from the randomized, placebo-controlled phase 3 RADIANT-2 study.

Background: In the phase 3 RADIANT-2 study, everolimus plus octreotide long-acting repeatable (LAR) showed improvement of 5.1 months in median progression-free survival versus placebo plus octreotide LAR among patients with advanced neuroendocrine tumors associated with carcinoid syndrome. The progression-free survival P-value was marginally above the prespecified threshold for statistical significance. Here, we report final overall survival (OS) and key safety update from RADIANT-2. Patients and methods: The RADIANT-2 trial compared everolimus (10 mg/day, orally; n = 216) versus placebo (n = 213), both in conjunction with octreotide LAR (30 mg, intramuscularly, every 28 days). Patients, unblinded at the time of progression or after end of double-blind core phase following primary analysis, were offered open-label everolimus with octreotide LAR (open-label phase). In the open-label phase, patients had similar safety and efficacy assessments as those in the core phase. For OS, hazard ratios (HRs) with 95% CIs using unadjusted Cox model and a Cox model adjusted for prespecified baseline covariates were calculated. Results: A total of 170 patients received open-label everolimus (143 crossed over from the placebo arm; 27 in the everolimus arm continued to receive the same treatment after unblinding). The median OS (95% CI) after 271 events was 29.2 months (23.8-35.9) for the everolimus arm and 35.2 months (30.0-44.7) for the placebo arm (HR, 1.17; 95% CI, 0.92-1.49). HR adjusted for baseline covariates was 1.08 (95% CI, 0.84-1.38). The most frequent drug-related grade 3 or 4 AEs reported during the open-label phase were diarrhea (5.3%), fatigue (4.7%), and stomatitis (4.1%). Deaths related to pulmonary or cardiac failure were observed more frequently in the everolimus arm. Conclusion: No significant difference in OS was observed for the everolimus plus octreotide LAR and placebo plus octreotide LAR arms of the RADIANT-2 study, even after adjusting for imbalances in the baseline covariates. Clinical Trial Number: NCT00412061, www.clinicaltrials.gov.

The management of neuroendocrine tumours: current and future medical therapy options.

Neuroendocrine tumours (NETs) are a genetically diverse group of malignancies that sometimes produce peptides causing characteristic hormonal syndromes. NETs can be clinically symptomatic (functioning) or silent (non-functioning); both types frequently synthesise more than one peptide, although often these are not associated with specific syndromes. Based on data from various sources, the incidence and prevalence of NETs is increasing. The primary treatment goal for patients with NETs is curative, with symptom control and the limitation of tumour progression as secondary goals. Surgery is the only possible curative approach and so represents the traditional first-line therapy. However, as most patients with NETs are diagnosed once metastases have occurred, curative surgery is generally not possible. Patients therefore require chronic postoperative medical management with the aim of relieving symptoms and, in recent years, suppressing tumour growth and spread. Somatostatin analogues, such as octreotide long-acting repeatable (LAR), can improve the symptoms of carcinoid syndrome and stabilise tumour growth in many patients. Results from the PROMID study show that octreotide LAR 30mg is an effective antiproliferative treatment in patients with newly diagnosed, functionally active or inactive, well-differentiated metastatic midgut NETs. An antiproliferative effect can also be achieved with everolimus, and combination therapy with octreotide LAR has shown synergistic antiproliferative activity. In the future, pasireotide, the multi-receptor targeted somatostatin analogue, has the potential to be an effective therapy for de novo or octreotide-refractory carcinoid syndrome and for inhibiting tumour cell proliferation. Peptide receptor radiotherapy with [90]yttrium-DOTATOC or [177]lutetium-DOTATE is also a new interesting treatment option for NETs.

Oncolytic viruses for the treatment of neuroendocrine tumors.

Oncolytic viruses are emerging as anticancer agents, and they have also shown great promise for use against neuroendocrine tumors. Many viruses have a natural tropism for replication in tumor cells. Others can be genetically engineered to selectively kill tumor cells. Viruses have some advantages as therapeutic agents over current cytotoxic drugs and small molecules. They replicate in tumor cells and thereby increase in number over time leading to increased dosage. They are immunogenic and can alter the immunosuppressive tumor microenvironment and activate immune effector cells. They have also been shown to be able to kill drug-resistant cancer stem cells. This article reviews the recent literature on oncolytic viruses used so far for neuroendocrine tumors and indicates important issues to focus on in the future.

Gastrointestinal neuroendocrine tumors.

Gastrointestinal neuroendocrine tumors (GI-NETs) are a genetically diverse group of malignancies that sometimes produce peptides causing characteristic hormonal syndromes. NETs can be clinically symptomatic (functioning) or silent (non-functioning); both types frequently synthesize more than one peptide, although often these are not associated with specific syndromes. Based on data from various sources the incidence and prevalence of GI-NETs is increasing. Surgery is the only possible curative approach and so represents the traditional first-line therapy. However, as most patients with NETs are diagnosed once metastases have occurred, curative surgery is generally not possible. Patients therefore require medical management with the aim of relieving symptoms and suppressing tumor growth and spread. Somatostatin analogues can improve the symptoms of carcinoid syndrome and stabilize tumor growth (PROMID study) in many patients. An antiproliferative effect can also be achieved with the m-TOR inhibitor everolimus, alone or in combination with octreotide LAR. The vascular endothelial growth factor inhibitor sunitinib has demonstrated antitumor effects in pancreatic NETs. Pasireotide, the multi-receptor targeted somatostatin analogue, has the potential to be an effective therapy for de novo or octreotide-refractory carcinoid syndrome. Peptide receptor radiotherapy with yttrium 90-DOTATOC or lutetium 177-DOTATE are also new interesting treatment options for NETs.

Treatment with cisplatin and etoposide in patients with neuroendocrine tumors.

BACKGROUND: Patients with malignant endocrine pancreatic tumors (EPTs) are responsive to combinations of chemotherapy with streptozotocin and 5-fluorouracil/doxorubicin, whereas patients with malignant carcinoids are not. For both categories of patients, alpha-interferon and/or somatostatin analogs can produce long-lasting responses. Cisplatin in combination with etoposide has been suggested to be effective in patients with malignant neuroendocrine carcinomas. The authors used this therapy as second-line or third-line treatment in patients with poorly differentiated and/or rapidly progressing disease. METHODS: Thirty-six patients with histopathologically verified malignant neuroendocrine tumors were included: Eighteen tumors were of foregut origin, of which 5 were atypical, and 15 tumors were EPTs, of which 4 were poorly differentiated endocrine carcinomas. Three tumors were of midgut origin. The median patient age was 47.5 years. The median duration of disease from the time of diagnosis was 12 months. All patients had metastatic disease. Thirty of 36 patients had received previous treatment. Etoposide was given at a dose of 100 mg/m(2) per day for 3 days, and cisplatin was given at a dose of 45 mg/m(2) on Days 2 and 3 as a continuous intravenous infusion that was repeated every 4 weeks. RESULTS: Ten of 18 patients with foregut carcinoids (56%) responded radiologically and/or biochemically, with a median duration of 9 months; and 7 of 14 patients with EPTs (50%) responded radiologically and/or biochemically, with a median duration of 9 months. No difference in response was seen between patients with atypical or typical foregut carcinoids or between patients with well differentiated or poorly differentiated endocrine pancreatic carcinoma. Nineteen of 36 patients (53%) experienced World Health Organization (WHO) Grade 1-2 nephrotoxicity, and 23 patients (64%) suffered from WHO Grade 3-4 neutropenia. CONCLUSIONS: The combination of cisplatin and etoposide can produce significant responses in patients with heavily pretreated and poorly differentiated/rapidly progressing neuroendocrine tumors. The toxicity is considerable, and nephrotoxicity is the dose limiting factor.

Efficacy and safety of prolonged-release lanreotide in patients with gastrointestinal neuroendocrine tumors and hormone-related symptoms.

PURPOSE: To evaluate the prolonged release (PR) of the long-acting somatostatin analog lanreotide in patients with gastrointestinal neuroendocrine tumors and its effect on hormone-related symptomatology, tumor markers, tumor size, tolerability, and quality of life (QOL). PATIENTS AND METHODS: Eligible patients had the following substantial daily symptoms: for patients with carcinoid tumors, three or more stools and/or 1.5 or more flushing episodes; for patients with gastrinoma, greater than 50% elevated basic acid output; and for patients with vasoactive intestinal peptide-secreting tumors (VIPomas), four or more stools and/or a stool volume of >/= 800 mL, a measurable tumor, and an elevated biochemical tumor marker (>/= two times the upper limit of the normal reference range). Lanreotide PR was administered intramuscularly every 14 days at 30 mg for 6 months. We measured efficacy by studying symptoms, tumor markers, tumor size, and QOL. Side effects were scored according to the National Cancer Institute's toxicity grading system and ultrasound examination of the gallbladder. RESULTS: Fifty-five patients were included in the study (48 patients with carcinoid tumors, six patients with gastrinoma, and one patient with VIPoma). Symptomatic improvement (> 50% reduction) occurred in 38% of the assessable patients with carcinoid tumors, in 67% of the gastrinoma patients, and in the VIPoma patient. Tumor markers normalized in two of 45 assessable patients, 19 patients exhibited a reduction (> 50%), 19 patients exhibited no change, and tumor markers rose by more than 50% in five patients. Tumor size was reduced in two of 31 assessable patients and remained stable in 25 patients; four patients experienced progression. QOL assessments after 1 month showed improvements in emotional and cognitive function, and diminished fatigue, sleeping disorders, and diarrhea. Eight of 30 assessable patients developed gallstones. CONCLUSION: Lanreotide PR is a well-tolerated somatostatin analog with significant clinical, biochemical, and antitumor effects that bring about a significant improvement in QOL for patients with neuroendocrine tumors.

Liver embolizations of patients with malignant neuroendocrine gastrointestinal tumors.

BACKGROUND: Patients with neuroendocrine gastrointestinal tumors usually present with inoperable metastatic disease and severe hormonal symptoms. Specific chemotherapy, interferon-alpha (IFN), and somatostatin analogs are established therapies for these patients, but all of them eventually fail. Hepatic arterial embolization can provide reduction of both hormonal symptoms and tumor burden in these patients. METHODS: Between 1981 and 1995, a total of 55 liver embolizations with gel foam powder were performed on 41 patients with histopathologically verified neuroendocrine tumors; 29 had carcinoid tumors and 12 had endocrine pancreatic tumors (EPTs). All patients had received medical treatment, including chemotherapy (n = 18), IFN (n = 31), and octreotide (n = 19), and were experiencing treatment failure when liver embolization was performed at a median of 37 months after diagnosis of liver metastases. Medical treatment was continued after embolization. RESULTS: An overall objective response was noted in 15 of 29 patients with carcinoid tumors (52%). The median duration of effect was 12 months in patients with midgut carcinoid tumors. An overall objective response was observed in 6 of 12 patients with EPTs (50%), with a median duration of effect of 10 months. Adverse events were observed, and, in agreement with earlier reports, the rate of serious complications was 10%. Survival analyses showed a median survival of 80 months and a 5-year survival rate of 60% from the performance of embolization on patients with midgut carcinoid tumors, whereas for patients with EPTs the median survival from embolization was only 20 months. CONCLUSIONS: Liver embolizations performed relatively late in the clinical course in our series appeared to be as effective as "early" embolizations in other series of patients with carcinoid tumors. The results for those with EPTs were poorer, and earlier embolizations may result in better outcomes for these patients. Considering the morbidity associated with the procedure, it is imperative to select patients according to extent of liver involvement, severity of carcinoid heart disease, and somatostatin receptor status.

Antibodies to interferon-alpha in treated cancer patients: incidence and significance.

Antibodies to interferon-alpha (IFN-alpha) are found in some patients being treated with this cytokine. In studies in which two recombinant IFN-alpha preparations were directly compared in cancer patients, those given IFN-alpha2a were found to have neutralizing antibodies in their serum significantly more often than those given IFN-alpha2b (p <0.001). Patients who develop neutralizing antibodies are more likely to have a clinical relapse and to become resistant to further treatment with at least the IFN preparation initially used for their treatment. In 10 studies in cancer patients, such an outcome was found in 63% of those who developed antibodies but in only 13% of those who did not. These data are tabulated.

Carcinoid tumours.

Carcinoid tumours offer a diagnostic and therapeutic challenge. Although new biochemical markers and improved methods for tumour detection, including PET and somatostatin receptor scintigraphy, have been developed during the last two decades many patients are still diagnosed at late stages of the disease. This is supported by the fact that the age of diagnosis is about the same today as it was 10 years ago. It is our opinion that plasma chromogranin A levels should be be determined in all patients which are investigated because of symptoms that might be connected to a neuroendocrine tumour. In cases with flushing or diarrhoea, U-5-HIAA should also be determined and these two tumour markers are enough to diagnose most patients with midgut carcinoid tumours. In patients with foregut or hindgut tumours other specific hormones should be included. For the localization procedure conventional radiological techniques including CT, MRI and ultrasound investigations should be supplemented with somatostatin receptor scintigraphy. Endoscopic ultrasound investigations might in the future be relevant for diagnosis of duodenal carcinoids, whereas gastric and rectal carcinoids are diagnosed by endoscopy. A combination of more aggressive surgery combined with medical treatment such as somatostatin analogues and alpha-interferon has significantly increased the survival rates in patients with classical midgut carcinoid tumours. Metastatic foregut and hindgut tumours are still a therapeutic challenge and it is important in the future to classify all carcinoid tumours based on specific tumour biology patterns. Such a tumour biology based treatment is a prerequisite for a more individually based therapy in the future.

The use of new somatostatin analogues, lanreotide and octastatin, in neuroendocrine gastro-intestinal tumours.

In an open phase III study, octastatin was given as a continuous subcutaneous (s.c.) infusion to 35 patients (mean age 62 years) with malignant neuroendocrine gastro-intestinal tumours and the carcinoid syndrome. The wash-out was often incomplete because of the advanced stage of disease. The starting dose of 1.5 mg/24 h was increased up to 3.0 mg/24 h at 3 months in some patients. The carcinoid syndrome disappeared in 20% of patients at 3 months and in 23% at 6 months, with 43 and 45% of patients, respectively, experiencing an improvement. The mean Karnovsky index increased by > 10% in 40% of patients at 3 and 6 months. Urinary 5-hydroxyindoleacetic acid (U-5-HIAA) levels at 3 months normalised in 1 patient, fell in 20% (by > 50%; p = 0.0021) and stabilised in 66%. The respective values at 6 months were 1, 17% (p = 0.023) and 60%. There was also a significant decrease in plasma chromogranin levels at 3 months (p = 0.042), which did not persist at 6 months. Tumour size fell (by > 50%) in 1 patient by 6 months but this patient had undergone chemoembolisation one month prior to the start of the study. Most patients had tumour size stabilisation (76 and 68%) or progression (20 and 24%) at 3 and 6 months, respectively. Dose escalation from 1.5 to 3.0 mg did not significantly improve clinical, biochemical or tumour responses. The treatment was well tolerated with minor adverse events. In an open pilot phase II study of 19 patients (mean age 58 years), patients were given high dose somatuline with a maintenance dose of 12,000 mg/day in 4 divided s.c. injections. U-5-HIAA, which was elevated in 13 patients with a mean of 444 mumol/day before the start, was reduced to 58% of baseline at 3 months, 68% at 6 months (p = 0.04), 66% at 9 months and 75% at 12 months (p = 0.14). P-chromogranin was elevated in 18 patients, with a mean of 5,300 micrograms/l before the start, and was reduced to 52, 55, 63 and 64% of the baseline at 3, 6 (p = 0.039), 9 and 12 (p = 0.013) months, respectively. In the responding patients, apoptosis was induced.

Characterization of anti-interferon-alpha antibodies appearing during recombinant interferon-alpha 2a treatment.

Patients with malignant midgut carcinoid tumours received recombinant interferon-alpha 2a (rIFN-alpha 2a) or rIFN-alpha 2a and chemotherapy (streptozocin and doxorubicin) for 6 months, and then rIFN-alpha 2a alone. Antibodies, mainly of IgG type, binding to rIFN-alpha 2a developed in nine of 22 patients (41%), as determined by immunoassay. In seven patients, antibodies also neutralized the biologic (anti-viral) activity of rIFN-alpha 2a. Anti-IFN-alpha 2a antibodies were equally frequent in both sexes and treatment groups, but were not observed in those patients (n = 8) that had previously received other types of IFN. Antibodies appeared after a median of 6 months of rIFN-alpha 2a treatment and had a median duration of 6 months. The anti-IFN-alpha 2a antibody titres declined with time with no obvious relation to change of therapy, also during continued IFN-alpha 2a treatment. High titres of neutralizing antibodies appeared to impair anti-tumoural effects in individual potential responders. Anti-IFN-alpha 2a antibodies further examined in six patients bound to native IFN-alpha subtypes present in both allogenic and autologous leucocyte IFN-alpha. Such autoantibodies neutralized the biologic activity of autologous IFN-alpha in two patients, and in a third were partially neutralizing.

Octreotide and interferon alfa: a new combination for the treatment of malignant carcinoid tumours.

24 patients with malignant carcinoid tumours received octreotide and interferon alfa (IFN-alpha). All the patients initially received octreotide 50-100 micrograms, twice daily. When progressive symptoms or increasing biochemical markers were observed, the daily dose was raised to a median 300 micrograms. If the initial dose proved ineffective or if no improvement was seen after escalation, IFN-alpha was added (median 9 MU subcutaneously per week). After the addition of IFN-alpha, 17 of the 22 patients (77%) with elevated urinary 5-hydroxyindoleacetic acid showed a significant (> 50%) reduction. Only 1 patient progressed and 4 had continuously stable biochemical disease. No significant reduction in tumour size was noted; in 5 patients, the tumour continued to grow despite decreasing hormone levels. 18 patients had carcinoid syndrome when IFN-alpha was added in 10 (56%) symptoms ameliorated. Thus, the addition of IFN-alpha is beneficial for patients with malignant carcinoid tumours that progress and/or who do not respond to octreotide.

Autoimmunity after alpha-interferon therapy for malignant carcinoid tumors.

OBJECTIVE: To determine the incidence of autoantibodies and autoimmune disease and their influence on therapeutic results during alpha-interferon treatment in patients with malignant midgut carcinoid tumors. DESIGN: Consecutive sample of patients. SETTING: University hospital. PATIENTS: One hundred thirty-five patients (70 women, 65 men; median age, 59 years) with biopsy-proven tumors, liver metastases, and no autoimmune disease. INTERVENTIONS: Leukocyte alpha-interferon (n = 88) or alpha-interferon 2b (n = 47) three times a week. MAIN OUTCOME MEASURES: Signs and symptoms of autoimmune disease or development of autoantibodies to thyroid antigens, nuclear antigens, or gastric parietal cells. Tumor responses were determined by reduced liver metastases or reduced urinary 5-hydroxyindole acetic acid excretion, or both. RESULTS: Twenty-five patients (19%) developed the following autoimmune disorders after a median of 9 months of therapy: thyroid disease (n = 18), systemic lupus erythematosus (n = 1), pernicious anemia (n = 4), and vasculitis (n = 2). Antibodies to microsomal thyroid antigen or thyroglobulin were detected in 16 patients before therapy and in another 11 patients during therapy. Antinuclear antibodies were detected in 16 patients before and in another 19 patients during therapy. Clinical thyroid disease developed in more than 60% of patients who had or developed thyroid antibodies but in only 7% of initially autoantibody-negative patients. Autoimmunity did not correlate with objective tumor response. CONCLUSION: Patients with malignant carcinoid tumors may develop autoimmune disease during alpha-interferon therapy, especially when autoantibodies are present. They should therefore be monitored for autoimmunity, which does not appear, however, to influence tumor responses.

Possible induction of systemic lupus erythematosus by interferon-alpha treatment in a patient with a malignant carcinoid tumour.

Interferon-alpha (IFN-alpha) is currently used in the treatment of various malignant tumours. Development of different autoimmune disorders has been reported in some patients during IFN-alpha therapy. Systemic lupus erythematosus (SLE) after treatment with IFN-alpha has not been described, although a majority of SLE patients have demonstrable serum levels of IFN-alpha, which correlate with disease activity and have been suggested to be of pathogenetic significance. In this paper we describe a patient with a malignant carcinoid tumour who developed a SLE-like syndrome during treatment with leucocyte IFN-alpha. The patient developed myalgia and low grade arthritis in multiple joints together with a high titre of antinuclear antibodies (ANA) and anti-dsDNA antibodies. After the treatment was stopped, the symptoms subsided although a moderate ANA titre persisted. However, the tumour continued to regress despite cessation of IFN-alpha therapy. During a short course with recombinant IFN-alpha the syndrome relapsed, supporting the concept that the SLE syndrome was precipitated by IFN-alpha. A connection between IFN-alpha treatment, the induced autoimmune disorder and regression of the carcinoid tumour is suggested.