A dose-escalation study of recombinant interferon-alpha in patients with a metastatic carcinoid tumour

Recent Advances in the Diagnosis and Management of Carcinoid Syndrome

Carcinoid syndrome, a paraneoplastic condition linked with the release of multiple humoral factors, affects around 30-40% of patients with well-differentiated neuroendocrine tumours. Carcinoid syndrome has a major and unfavourable impact on patients' quality of life; it raises costs when compared to non-functioning neuroendocrine tumours; and it causes patients' lifestyles to alter, such as food, job, physical activity, and social life. Somatostatin analogues have been the first-line therapy for individuals with neuroendocrine tumours and carcinoid disease for decades. While these drugs give considerable relief from carcinoid syndrome symptoms, clinical progression is unavoidable, necessitating further research into newer treatment measures. Carcinoid tumours are sometimes difficult to diagnose because of their vague or nonspecific symptoms. There have been several advancements in all aspects of carcinoid syndrome, as well as novel therapeutics, in the previous few years. New epidemiological studies show that it is becoming more common; increasing insights into the pathogenesis of its various clinical manifestations and its natural history: definition of prognostic factors; new methods to verify its presence; the development of new drugs to treat its various manifestations, both initially and in somatostatin-refractory cases; and an increased understanding of the pathogenesis, natural history, and management of the disease. An all language literature search was conducted on MEDLINE, COCHRANE, EMBASE, and Google Scholar till November 2021. The following search strings and Medical Subject Headings (MeSH) terms were used: "Recent advances", "Carcinoid syndrome", "Neuroendocrine Neoplasms" and "Carcinoid heart disease". We comprehensively reviewed the literature on the pathogenesis, clinical features, and newer treatment modalities for Carcinoid Syndrome. Recent advancements in research and management have resulted from advances in our understanding of the aetiology of carcinoid syndrome. The development of molecular indicators of aggressiveness improved serum tumour markers, and the molecular aetiology of carcinoid heart disease are all possible because of advances in molecular biology. We conducted a comprehensive review to update knowledge regarding the pathophysiology, diagnostic protocols, and current and newer treatments for carcinoid syndrome, which presently requires a multidisciplinary approach, due to the complexity of the illness's aetiology, diagnosis, and therapy.

Peptide Receptor Radionuclide Therapy With 177Lu-DOTATATE for Symptomatic Control of Refractory Carcinoid Syndrome

CONTEXT

Peptide receptor radionuclide therapy (PRRT) with [Lutetium-177-DOTA0-Tyr3]octreotate (177Lu-DOTATATE) results in an increase of progression-free survival and quality of life in patients with progressive, well-differentiated neuroendocrine neoplasms (NENs).

OBJECTIVE

To study the effect of 177Lu-DOTATATE in patients with carcinoid syndrome and radiologically stable or newly diagnosed disease treated solely for the purpose of symptom reduction.

DESIGN

Retrospective cohort study.

SETTING

Tertiary care hospital.

PATIENTS

Twenty-two patients with a metastatic midgut NEN, elevated urinary 5-hydroxyindolacetic acid excretion, and flushing and/or diarrhea despite treatment with a somatostatin analog, without documented disease progression.

INTERVENTION

PRRT with 177Lu-DOTATATE (intended cumulative dose: 29.6 GBq) with a primary aim to reduce symptoms.

RESULTS

After PRRT, mean bowel movement frequency (BMF) decreased from 6.1 ± 3.4 to 4.6 ± 3.6 per day (P = 0.009). Flushes decreased from 4.3 ± 2.9 to 2.4 ± 2.7 flushes per day (P = 0.002). A decrease of BMF of more than 30% occurred in 47% of patients with baseline BMF of 4 or more (n = 17). In patients with ≥2 episodes of flushing a day (n = 15), 67% of patients had more than 50% decrease of daily flushing. A decrease in urinary 5-hydroxyindolacetic acid excretion of more than 30% was seen in 56% of patients. The European Organization for Research and Treatment of Cancer-Core Module diarrhea subscale score showed a trend toward improvement by an average of 16.7 ± 33.3 points (P = 0.11).

CONCLUSION

PRRT with 177Lu-DOTATATE effectively reduced diarrhea and flushing in patients with carcinoid syndrome and can be considered for symptomatic treatment of carcinoid syndrome insufficiently controlled with somatostatin analogs.

Spotlight on telotristat ethyl for the treatment of carcinoid syndrome diarrhea: patient selection and reported outcomes

Neuroendocrine tumors (NETs) are rare cancers with an associated prolonged survival in some patients. A proportion of patients diagnosed with NETs will present with carcinoid syndrome symptoms, characterized by diarrhea, flushing and/or wheezing. This review summarizes the current treatment options for carcinoid syndrome, focusing on the latest novel treatment option, telotristat ethyl. In addition, information on patient-reported outcomes and impact of carcinoid syndrome on quality of life (QOL) and improvement of following treatment with telotristat ethyl are reviewed. This article also provides an overview of the current QOL questionnaires for patients with NETs and addresses unmet needs in this field of patient-reported outcomes.

Carcinoid Syndrome: Updates and Review of Current Therapy

OPINION STATEMENT

Carcinoid syndrome (CS) is a complex disorder caused by functional neuroendocrine tumors (NETs). This debilitating disease is characterized by hyper-secretion of biologically active substances eliciting major hormonal symptoms burden and fibrotic changes that are often challenging for management. There have been a number of insights that have substantially advanced treatments since the introduction of somatostatin analogs (SSAs). Second-line treatments are needed in a substantial proportion of patients with advanced disease that have uncontrolled hormone secretion on the highest labeled doses of SSAs. International guidelines suggest several available options including dose escalation of SSAs, interferon alpha, everolimus, radionuclide therapy, liver-directed therapies, and the novel tryptophan hydroxylase 1 inhibitor, telotristat ethyl. The clear preference of one second-line therapy over the other is not stated since their relative and long-term efficacy are largely unknown, and standardized approach of hormonal response assessment is lacking in the literature. In the clinical setting, the treatment of CS is guided in conjunction with patients' performance status, tumor origin, grade, stage, and growth rate, with regard to both anti-hormonal, as well as anti-proliferative effect. There is an unmet need for further well-designed randomized placebo-controlled and head-to-head studies that systematically assess CS symptom control and biochemical response following a specific intervention.

Management of carcinoid syndrome: a systematic review and meta-analysis

Carcinoid syndrome (CS) is a debilitating disease caused by functional neuroendocrine tumors. Several treatment options are available to alleviate the hormonal symptoms, but their relative efficacy is unknown. Online databases were searched for publications on the treatment of CS symptoms. Independent reviewers assessed relevant publications for study quality and outcome. Meta-analysis of the outcomes of the intervention on CS-related symptoms was stratified by the type of treatment. We found 3682 therapeutic interventions on CS-specific outcomes were collected from 93 studies. Overall, the study qualities were poor with only six randomized controlled clinical trials. The somatostatin analogs octreotide and lanreotide induced symptomatic improvement in 65-72% and biochemical response in 45-46% of patients. An increase in dose or frequency or interclass switch led to a reduction of flushes and/or diarrhea in 72-84% of cases. Retrospective, institutional series showed that liver-directed therapy can improve symptoms in 82% of CS patients with a liver-dominant disease. The serotonin synthesis inhibitor telotristat ethyl reduced bowel movements in 40% of patients with diarrhea refractory to somatostatin analogs. Interferon-alpha controlled CS symptoms in 45-63% of cases. Favorable response has been noted after radionuclide therapy in subgroup analyses of studies not specifically involving CS patients. Chemotherapy and everolimus did not induce a significant response in the CS. We conclude that several treatment lines can be offered to patients suffering from the carcinoid syndrome. Initiation of randomized controlled trials with a primary outcome on carcinoid syndrome symptoms is strongly recommended.

Management of carcinoid syndrome: a systematic review and meta-analysis

Carcinoid syndrome (CS) is a debilitating disease caused by functional neuroendocrine tumors. Several treatment options are available to alleviate the hormonal symptoms, but their relative efficacy is unknown. Online databases were searched for publications on the treatment of CS symptoms. Independent reviewers assessed relevant publications for study quality and outcome. Meta-analysis of the outcomes of the intervention on CS-related symptoms was stratified by the type of treatment. We found 3682 therapeutic interventions on CS-specific outcomes were collected from 93 studies. Overall, the study qualities were poor with only six randomized controlled clinical trials. The somatostatin analogs octreotide and lanreotide induced symptomatic improvement in 65–72% and biochemical response in 45–46% of patients. An increase in dose or frequency or interclass switch led to a reduction of flushes and/or diarrhea in 72–84% of cases. Retrospective, institutional series showed that liver-directed therapy can improve symptoms in 82% of CS patients with a liver-dominant disease. The serotonin synthesis inhibitor telotristat ethyl reduced bowel movements in 40% of patients with diarrhea refractory to somatostatin analogs. Interferon-alpha controlled CS symptoms in 45–63% of cases. Favorable response has been noted after radionuclide therapy in subgroup analyses of studies not specifically involving CS patients. Chemotherapy and everolimus did not induce a significant response in the CS. We conclude that several treatment lines can be offered to patients suffering from the carcinoid syndrome. Initiation of randomized controlled trials with a primary outcome on carcinoid syndrome symptoms is strongly recommended.

Medical Treatment of Neuroendocrine Tumors

Background

Tumors of the neuroendocrine system are characterized by amine precursor uptake and decarboxylation, and they represent a heterogeneous group of carcinomas including carcinoids, islet cell carcinomas of the pancreas, medullary thyroid carcinomas and Merkel cell carcinomas. Their similar cytochemical and ultrastructural properties sustain the hypothesis of a common embryologic origin within the neural crest. Many of these tumors grow slowly, and reducing tumor burden represents the treatment of choice. However, when surgery is not feasible, medical treatment has to be considered. Therapeutic approaches in metastatic disease often do not consider the different biologic behaviors of these neoplasms. Moreover, efficacy of the treatment is associated with lack of a clear definition of the type of response: objective, symptomatic or biochemical.

Methods

In this review we have analyzed the different medical approaches used in the treatment of neuroendocrine tumors in an attempt to define their precise role in the different neoplasms.

Results

In carcinoid tumors, immunotherapy and the somatostatin analogue can be efficaciously used for the control of carcinoid syndrome. For inhibition of tumor growth, chemotherapy should be used only in patients with rapidly progressive disease, and the results are still unsatisfactory.

Conclusions

Although all these tumors appear to have similar cytochemical properties, the responsiveness of the various neoplasms is very different. In the future, a specific treatment modality and a clear definition of the type of response (objective, symptomatic or biochemical) need to be defined for each type of neuroendocrine tumor.

Biotherapies for GEP-NETs

Biological treatment for GI neuroendocrine tumours (NETs) includes treatment with somatostatin analogues and alpha interferons. Both of these therapies were developed in the early 1980's and initially for treatment of a carcinoid syndrome in patients with small intestinal NETs. Later on tumour biology studies indicated that well differentiated NETs (G1-tumours) benefit from treatment with somatostatin analogues and alpha interferons. Both agents give symptomatic improvement in patients with functioning tumours in 40-60% of the patients, biochemical responses in 50-70% of the patients and significant tumour shrinkage in 5-10% of the patients. Combination therapy with somatostatin analogues and alpha interferon has demonstrated some clinical benefit.

IN CONCLUSION

Somatostatin analogues and alpha interferons are still playing an important role and considered to be first-line treatment in functioning and in non-functioning well-differentiated NETs, (G1-tumours) and somatostatin analogues might also be applied to control clinical symptoms in G2-tumours with higher proliferation.

Endogenous type-I interferon activity is not associated with depression or fatigue in systemic lupus erythematosus

Patients with systemic lupus erythematosus (SLE) often suffer from depression and fatigue in addition to the physical manifestations of the autoimmune disease. Elevated production of type-I interferons (IFN-I) has been found in lupus patients and IFN-I can precipitate a variety of neuropsychiatric side effects. This study was conducted to evaluate the relationship between dysregulated IFN-I production and the presence of depression or fatigue in lupus patients. Through cross-sectional and longitudinal analysis we found no significant correlation between abnormal IFN-I levels (as measured by peripheral blood expression of IFN-I-stimulated genes) and neuropsychiatric manifestations. Elevation of endogenous serum IFN-I levels is unlikely to account for the depression and fatigue associated with SLE.

Neuroendocrine tumors. Biotherapy

This review gives an introduction to the classification and staging of neuroendocrine tumors, as the prognostic implications of these classifications influence therapeutic decisions. The indications for biotherapy are given, together with a short update on the mechanism of somatostatin analogs and interferon-alpha therapy. This is followed by an in-depth description of the use of biotherapy, its results with respect to symptomatic and antiproliferative treatment, as well as its side-effects.

Local treatment in unresectable hepatic metastases of carcinoid tumors: Experiences with hepatic artery embolization and radiofrequency ablation

Background

Hepatic metastases of carcinoid tumors cause incapacitating symptoms, but are usually diffuse and therefore unresectable. In this article we evaluate our experiences with local treatment techniques in the management of carcinoid patients with hepatic metastases and failing systemic treatment.

Methods

Fifteen consecutive carcinoid patients (11 men and 4 women; median age 60 years; range 45–71 years) were treated with either hepatic artery embolization (HAE) with Ivalon particles or radiofrequency ablation (RFA) (percutaneously or intra-operatively). Follow-up evaluation was performed by CT scan and 24-hours urinary 5-HIAA excretions.

Results

A total of 18 HAE's was performed in 13 patients, while 10 lesions in 3 patients were treated with RFA. Median follow-up was 12.5 months (2 – 25 months). Median duration of symptoms was 22 months (8 – 193 months). Median overall decrease of 5-HIAA excretion 2 months after HAE was 32% with tumor regression on CT-scan in 4 patients (30%) and improvement of symptoms with a median duration of 15 months in 3 of them (23%). Embolization led to fatal hepatic failure in one patient. The 3 patients treated with RFA showed a decrease of urinary 5-HIAA values of 34, 81 and 93% respectively, with tumor regression in all of them. Improvement of symptoms was reported in 2 patients up to 25 months.

Conclusion

Liver embolization performed late in the clinical course had limited effect on symptoms and biochemical and radiological parameters. First experiences with RFA are favorable and might encourage to apply RFA more widely in metastatic carcinoid.

Potential of interferon-alpha in solid tumours: part 2

The second part of this review examines the use of recombinant interferon-alpha (rIFNalpha) in the following solid tumours: superficial bladder cancer, Kaposi's sarcoma, head and neck cancer, gastrointestinal cancers, lung cancer, mesothelioma and ovarian, breast and cervical malignancies. In superficial bladder cancer, intravesical rIFNalpha has a promising role as second-line therapy in patients resistant or intolerant to intravesical bacille Calmette-Guérin (BCG). In HIV-associated Kaposi's sarcoma, rIFNalpha is active as monotherapy and in combination with antiretroviral agents, especially in patients with CD4 counts >200/mm(3), no prior opportunistic infections and nonvisceral disease. rIFNalpha has shown encouraging results when used in combination with retinoids in the chemoprevention of head and neck squamous cell cancers. It is effective in the chemoprevention of hepatocellular cancer in hepatitis C-seropositive patients. In neuroendocrine tumours, including carcinoid tumour, low-dosage (</=3 MU) or intermediate-dosage (5 to 10 MU) rIFNalpha is indicated as second-line treatment, either with octreotide or alone in patients resistant to somatostatin analogues. Intracavitary IFNalpha may be useful in malignant pleural effusions from mesothelioma. Similarly, intraperitoneal IFNalpha may have a role in the treatment of minimal residual disease in ovarian cancer. In breast cancer, the only possible role for IFNalpha appears to be intralesional administration for resistant disease. IFNalpha may have a role as a radiosensitising agent for the treatment of cervical cancer; however, this requires confirmation in randomised trials. On the basis of current evidence, the routine use of rIFNalpha is not recommended in the therapy of head and neck squamous cell cancers, upper gastrointestinal tract, colorectal and lung cancers, or mesothelioma. Pegylated IFNalpha (peginterferon-alpha) is an exciting development that offers theoretical advantages of increased efficacy, reduced toxicity and improved compliance. Further data from randomised studies in solid tumours are needed where rIFNalpha has activity, such as neuroendocrine tumours, minimal residual disease in ovarian cancer, and cervical cancer. A better understanding of the biological mechanisms that determine response to rIFNalpha is needed. Studies of IFNalpha-stimulated gene expression, which are now feasible, should help to identify molecular predictors of response and allow us to target therapy more selectively to patients with solid tumours responsive to IFNalpha.

Carcinoid heart disease: an update

BACKGROUND

Carcinoid tumours are a poorly defined collection of lesions, histopathologically indistinguishable from gastroentero-pancreatic neuroendocrine tumours. In this report, we discuss epidemiology and survival, clinical presentation, carcinoid valvular heart disease (CVHD), histopathological considerations and treatment options.

METHODS

Review and update of the literature.

RESULTS

The term carcinoid suggests a disease entity, but with increasing knowledge it becomes progressively confusing. To avoid further confusion, it is advisable to define these tumours using differentiation, stage, primary site, known tumour products and an associated clinical syndrome. Incidence varies between 0.8 and 1.9/100,000 population. About 20% present with metastases, with a 5-year survival varying between 15% and 35%. Metastatic disease frequently accompanies the carcinoid syndrome (flushing, diarrhoea, wheezing and CVHD). CVHD incidence is about 50%, and seems unrelated to disease duration and tumour mass. An aetiological relation of CVHD with urinary 5-HIAA remains to be confirmed. Resection is the only curative option. Surgery can also offer prolonged palliation and is needed to restore bowel transit in obstructive/ischaemic bowel problems. Adequate palliation of hormone-related symptoms can also be achieved by somatostatin analogues, meta-iodo-benzyl-guanidine preparations and interferon-alpha formulations, all with a 70% response rate. Embolization of liver metastases has led to objective responses in about 50% of patients, but is accompanied by significant side effects.

CONCLUSIONS

Most patients are cured by surgery. Symptom relief is the main target in metastatic disease and can be achieved by a range of equally potent biologically active medications, debulking surgery and hepatic embolization.

Ectopic ACTH-syndrome due to a thymic carcinoid tumor

Investigating a recently developed Cushing Syndrome, we diagnosed in a 47-year-old woman an ectopic ACTH syndrome due to a metastatic carcinoid tumor, most likely a thymic carcinoid tumor. Combined therapy with sandostatin and nizoral and later on with sandostatin, metopirone and orimeten, was not able to suppress the hypercortisolism. A few weeks after surgical adrenalectomy, clinical deterioration ensued, culminating in the patient's death 7 months after diagnosis.

[Therapeutic advances of nuclear medicine in oncology]

With the development of new radiopharmaceuticals there is a tendency to apply nuclear medicine therapy for malignancies of higher incidence (lymphoma, prostate) than the ones which have been treated for many years (thyroid cancer, neuroendocrine tumours). One of the most important areas of current development in radionuclide cancer therapy is the monotherapeutic use of new or already available radiopharmaceuticals in preclinical or phase I studies and to a lesser degree in phase II trials. In this context, the radioimmunotherapy is showing important advances in the treatment of medullary thyroid carcinoma, malignant lymphomas en brain tumours with potential extension to neuroblastoma therapy. The development of DOTA as a chelating agent has lead to the use of Y-90-DOTATOC in the treatment of neuroendocrine tumours, particularly carcinoid tumours, and non-I131I-avid thyroid carcinomas. In an effort to improve tumour targeting together with simultaneous reduction of physiological organ uptake, 131I-MIBG is being used in combination with interferon a and pre-targeting with unlabelled MIBG in the treatment of carcinoid tumours. New routes of administration of radiopharmaceuticals (intratumoral, intra-arterial) have enhanced the treatment of malignancies of liver, pancreas and brain as well as the potential use of radioimmunotherapy by intravesical administration for bladder carcinoma. Another significant tendency in radionuclide therapy is its evolution from monotherapy towards a combined application with other anticancer modalities. Some recent examples of combined therapy with demonstrated anti-tumour effect are found in neuroblastoma (131I-MIBG and chemotherapy), bone metastases of prostatic carcinoma (addition of 89Sr to chemotherapy schedules), brain malignancies (adjuvant use of radioimmnunotherapy in relation to surgery and external radiotherapy) and lymphoma (radioimmunotherapy combined with chemotherapy or immunotherapy). Reinforcing this trend in phase II and III studies as well as the planning of multicenter trials following the guidelines and criteria of clinical oncology will determine the future advances in this field.

Treatment of metastatic carcinoid tumours, phaeochromocytoma, paraganglioma and medullary carcinoma of the thyroid with (131)I-meta-iodobenzylguanidine [(131)I-mIBG]

OBJECTIVE

Meta-iodo-benzyl-guanidine labelled with 131-iodine [(131)I-mIBG] has been used extensively for imaging tumours originating from the neural crest but experience with its therapeutic use is limited, particularly for non-catecholamine secreting tumours. In order to assess the therapeutic response and potential adverse effects of the therapeutic administration of (131)I-mIBG, we have reviewed all patients who had received this form of treatment in our department.

DESIGN

Retrospective analysis of the case notes of patients with neuroendocrine tumours who received treatment with (131)I-mIBG and were followed-up according to a defined protocol in a given time frame.

PATIENTS

Thirty-seven patients (18 with metastatic carcinoid tumours, 8 metastatic phaeochromocytoma, 7 metastatic paraganglioma and 4 metastatic medullary carcinoma of the thyroid) treated with (131)I-mIBG over a 15-year period were included in this analysis.

MEASUREMENTS

The symptomatic, hormonal and tumoural responses before and after (131)I-mIBG therapy over a median follow-up duration of 32 months (range 5-180 months) were recorded. Of the 37 patients (22 males; median age 51 years, range 18-81 years), 15 were treated with (131)I-mIBG alone whereas the other 22 received additional therapy.

RESULTS

A total of 116 therapeutic (131)I-mIBG doses were administered [mean cumulative dose 592 mCi (21.9 GBq); range 200-1592 mCi (7.4-58.9 GBq)]. None of the patients showed a complete tumour response. However, 82% of patients treated with (131)I-mIBG alone and 84% who received additional therapy showed stable disease over the period of follow-up. Overall survival during the period of the study was 71%. The overall 5-year survival rate was 85% (95% confidence interval, 72-99%) for all patients and 78% (95% confidence interval, 55-100%) for the carcinoid group alone, according to Kaplan-Meier analysis. Symptomatic control was achieved in all the patients treated with (131)I-mIBG alone, and in 72% of those receiving additional therapy. Hormonal control was noted in 50% and 57% of patients, respectively. (131)I-mIBG therapy was safe and well tolerated. Serious side-effects necessitating the termination of (131)I-mIBG therapy were seen in only 2 of our patients.

CONCLUSIONS

(131)I-mIBG therapy produces symptomatic and hormonal improvement and moderate tumour regression/stabilization in patients with metastatic neuroendocrine tumours with minimal adverse effects. It may be a valuable alternative or additional therapeutic option to the currently available conventional treatment modalities.

A pilot study of combination therapy with interferon-alpha-2a and 5-fluorouracil in metastatic carcinoid and malignant endocrine pancreatic tumours

BACKGROUND

In view of the encouraging single agent response rates to interferon and 5-fluorouracil (5-FU) in malignant carcinoid and endocrine pancreatic tumours and the theoretical benefits of combination therapy with 5-FU and interferon in other tumours a study was designed to look at the feasibility of this combination, given for 12 months, in these tumours.

PATIENTS AND METHODS

Patients were treated with 5-FU 750 mg/m2 by intravenous bolus every week and 3 Mega Units of recombinant interferon-alpha-2a subcutaneously 3 times per week increasing, as tolerated, to 6 then 9 MU. Fifteen patients were entered into the study.

RESULTS

One patient died suddenly of an unrelated illness and is not assessed. None of the remaining 14 patients had radiological evidence of response to treatment, although 6 had stable disease lasting for 7 to 64 weeks (median 40 weeks). Two patients did have biochemical evidence of a response, i.e., a 50% reduction in baseline urinary 5HIAA for 26 and 52 weeks. Treatment toxicity was significant. Six patients stopped treatment prematurely because of either nausea and/or diarrhoea. Overall treatment duration ranged from 4 to 64 weeks (median 7.5 weeks).

CONCLUSION

Overall we found the treatment to be disappointing in terms of tolerance and response rate and do not recommend its use in malignant carcinoid or endocrine pancreatic tumours.

Neoplastic lesions of the appendix

Neoplasms occur in 0.5 per cent of appendices. Ultrasonography or computed tomography is beneficial, but preoperative detection is rare. At operation, the diagnosis is considered in under half of cases. Mucocele, localized pseudomyxoma peritonei, benign tumours and most appendiceal carcinoids are cured by appendicectomy alone. Right hemicolectomy is indicated for: (1) invasive adenocarcinoma; (2) tumours close to the caecum; (3) lesions larger than 2 cm; (4) mucin production; (5) invasion of the lymphatics, serosa or mesoappendix; and (6) cellular pleomorphism with a high mitotic rate. Tumours of 1-2 cm, small mucinous carcinoids, adenocarcinoma confined to the mucosa, and tumours in children may be treated by appendicectomy alone at the surgeon's discretion. The 5-year survival rate associated with classical carcinoid is more than 90 per cent. The prognosis of mucinous carcinoid is intermediate between that of classical carcinoid and well differentiated adenocarcinoma. The prognosis of adenocarcinoma is determined by Dukes' stage and is similar, stage for stage, to that of colorectal carcinoma.

Interferons combined with chemotherapy in the treatment of stage III-IV non-small cell lung cancer--a randomised study

80 patients with previously untreated stage III-IV non-small cell lung cancer (NSCLC) were randomly assigned to receive chemotherapy (CT) alone (arm I: 26 patients) or the same CT combined with either interferon (IFN)-gamma (arm II: 27 patients) or with both IFN-gamma and IFN-alpha (arm III: 27 patients). The CT comprised cisplatin 60 mg/m2 intravenously (i.v.) day 1 and etoposide 100 mg/m2 i.v. days 1, 3 and 5, once every 28 days; the IFN therapy comprised either recombinant IFN-gamma 1b 0.2 mg/m2, subcutaneously, three times a week until day 25, or recombinant IFN-alpha 2c 6 x 10(6) U given according to the same schedule, and simultaneously with IFN-gamma. A maximum of six cycles were given. The treatment was discontinued if progressive disease (PD) was demonstrated. The mean numbers of cycles per patient given in the different arms were 3.6 (arm I), 3.0 (arm II) and 2.9 (arm III). The main reason for discontinuation in all arms was PD. 17 (28%) of the 61 evaluable patients achieved partial responses (35% in arm I, 29% in arm II and 35% in arm III, non-significant). No complete response was recorded. Haematological toxicity was dose-limiting in all arms: leucopenia (WHO grade 3) was observed universally, but more frequently in arm III (in 18% of cycles given). Only two episodes of grade 4 leucopenia were seen (arms II and III) and six episodes of grade 3-4 thrombocytopenia (arm III). Median survival was 6-7 months in all arms. The survival curve for arm II was slightly more favourable (non-significant) than those for other arms. The addition of IFN-gamma alone or IFN-alpha plus IFN-gamma to platinum-based CT did not improve response rates nor did it produce any significant survival benefit for patients with NSCLC. Increased haematological toxicity was observed when both IFNs were administered concomitantly with CT.

Practical aspects of cytokine therapy

Biological therapy with cytokines and growth factors represents a completely new approach in cancer therapy and forces us to adapt our research procedures originally tailored to cytotoxic agents. The lack of reliable predictive in vitro systems or animal models for biological agents and the fact that promising candidates must proceed rapidly to the clinic implies that a drug's therapeutic potential can only be assessed following careful studies in man. Consequently, the effectiveness of clinical trials must be improved by closely relating them to research programs utilizing material from cytokine-treated patients. In clinical practice, patients with low tumor burden may profit most from therapy with immunomodulators, which requires minimally effective doses rather than maximally tolerated dosages. Hemopoiesis can be influenced either by hemopoietic growth factors or by negative regulators, which may prevent stem cell damage during chemotherapy. According to the principles of autocrine growth mechanisms, resting malignant cells may be triggered into cell cycle by their growth factor(s), thus becoming more sensitive to chemotherapy. When discussing the fascinating aspects of the cytokine network, we must be aware that we are only beginning to understand the mechanisms of biological therapy and that close cooperation among preclinical and clinical scientists is required for its rational development.

Treatment of carcinoid syndrome with recombinant interferon alpha-2a

The prognosis and the quality of life of patients with carcinoid tumors is related either to symptoms from the substances secreted or to progressive tumor growth. Medical treatment with cytotoxic agents is of marginal value for increasing life expectancy and reducing clinical symptoms. Recent studies with interferon have shown interesting results. In the present investigation, 22 patients with carcinoid tumors and syndrome were treated with recombinant interferon alpha-2a (r-IFN alpha-2a) at the dose of 6 x 10(6) IU intramuscularly daily for 8 weeks and three times weekly thereafter. The primary tumor was localized in the foregut (n = 11), midgut (n = 7), hindgut (n = 1), and unknown site (n = 3). Most cases had liver metastasis. Seventeen patients had elevated 5-hydroxyindoloacetic acid (5-HIAA) excretion and 5 had flushing and/or diarrhea as the only clinical manifestation. Six cases presented a complete syndrome (flushing, diarrhea and 5-HIAA excretion). Control of symptoms was obtained in 80% and a 5-HIAA level reduction in 58% of the patients. The interferon treatment was more effective for control of the carcinoid syndrome than for control of tumor growth. The treatment was well tolerated and fever, myalgia, anorexia and fatigue were the most frequent side-effects.

Recombinant interferon alpha-2b in patients with metastatic apudomas: effect on tumours and tumour markers

Malignant carcinoid tumours, islet cell tumours and medullary carcinomas of the thyroid are tumours with similar clinical features. In patients with unresectable or metastatic tumours leukocyte interferon (IFN) and recombinant human (rh) IFN have demonstrated efficacy. Twenty-four evaluable patients with progressive tumours were treated with 2.5 megaunits rh IFN alpha-2b, administered once daily subcutaneously, for a median duration of 7 months (range 0.5-37+). Two carcinoid patients demonstrated a response in tumour size, 80% showed stable disease (SD). Sixty percent of the carcinoid patients with elevated urinary 5-hydroxyindoleacetic (5-HIAA) levels reached a biochemical partial response of the urinary 5-HIAA levels (median duration 13.5 months). In the patients with an islet cell or medullary tumour and an elevated tumour marker, the marker did not further increase. Of the 12 carcinoid patients evaluable for a symptomatic response, ten (83%) experienced a relieve of symptoms. IFN alpha-2b dose reduction or discontinuation due to toxicity was necessary in three and ten patients, respectively. No neutralising IFN alpha-2b antibodies developed despite prolonged treatment. In conclusion, IFN alpha-2b had a beneficial effect in patients with progressive tumours, while long-term IFN alpha-2b treatment did not augment neutralising antibodies. In view of the IFN alpha-2b-related toxicity, administration of IFN alpha-2b on alternating days may be preferable.