Biology and management of the midgut carcinoid

Flow-driven right-to-left cardiac shunting in a patient with carcinoid heart disease and patent foramen ovale without elevated right atrial pressure: a case report and literature review

Background

Carcinoid heart disease is present in approximately 20% of the patients with carcinoid syndrome and is associated with poor prognosis. It usually manifests with right-sided valvular involvement including tricuspid insufficiency and pulmonary stenosis. Patent foramen ovale (PFO) is present in approximately 50% of the patients with carcinoid heart disease which is twice higher than the general population. Right-to-left shunting through a PFO can occur either due to higher right atrial pressure than left (pressure-driven) or when the venous flow is directed towards the PFO (flow-driven) in the setting of normal intracardiac pressures. We report a rare case of flow-driven right-to-left atrial shunting via PFO in a patient with carcinoid heart disease.

Case summary

A 54-year-old male with a metastatic neuroendocrine tumour to liver presented with progressive shortness of breath for 5 months. Patient was found to be hypoxic with oxygen saturation of 78% and examination revealed a holosystolic murmur. Arterial blood gas showed oxygen tension of 43 mmHg. A transthoracic and transoesophageal echocardiogram showed aneurysmal inter-atrial septum with a PFO, severe tricuspid regurgitation directed anteriorly towards the inter-atrial septum leading to a marked right-to-left shunt. Right heart catheterization showed right atrial pressure of 8 mmHg, mean pulmonary artery pressure of 12 mmHg, and normal oxygen saturations in the right atrium, right ventricle, and pulmonary arteries. The patient then underwent closure of the PFO along with tricuspid valve and pulmonary valve replacement at an experienced cardiovascular surgical centre and has been asymptomatic since.

Conclusion

Right-to-left shunting through a PFO in patients with normal right atrial pressure can be successfully treated with closure of the PFO. Thus, understanding the mechanism of intracardiac shunts is important to accurately diagnose and treat this rare and fatal condition.

Update on Pathophysiology, Treatment, and Complications of Carcinoid Syndrome

Carcinoid syndrome (CS) develops in patients with hormone-producing neuroendocrine neoplasms (NENs) when hormones reach a significant level in the systemic circulation. The classical symptoms of carcinoid syndrome are flushing, diarrhoea, abdominal pain, and wheezing. Neuroendocrine neoplasms can produce multiple hormones: 5-hydroxytryptamine (serotonin) is the most well-known one, but histamine, catecholamines, and brady/tachykinins are also released. Serotonin overproduction can lead to symptoms and also stimulates fibrosis formation which can result in development of carcinoid syndrome-associated complications such as carcinoid heart disease (CaHD) and mesenteric fibrosis. Transforming growth factor beta (TGF-β) is one of the main factors in developing fibrosis, but platelet-derived growth factor (PDGF), basic fibroblast growth factor (FGF2), and connective tissue growth factor (CTGF or CCN2) are also related to fibrosis development. Treatment of CS focuses on reducing serotonin levels with somatostatin analogues (SSA's). Telotristat ethyl and peptide receptor radionuclide therapy (PRRT) have recently become available for patients with symptoms despite being established on SSA's. Screening for CaHD is advised, and early intervention prolongs survival. Mesenteric fibrosis is often present and associated with poorer survival, but the role for prophylactic surgery of this is unclear. Depression, anxiety, and cognitive impairment are frequently present symptoms in patients with CS but not always part of their care plan. The role of antidepressants, mainly SSRIs, is debatable, but recent retrospective studies show evidence for safe use in patients with CS. Carcinoid crisis is a life-threatening complication of CS which can appear spontaneously but mostly described during surgery, anaesthesia, chemotherapy, PRRT, and radiological procedures and may be prevented by octreotide administration.

Quadruple Valve Replacement for Carcinoid Heart Disease

INTRODUCTION

Carcinoid heart disease most frequently involves the tricuspid or, more rarely, the pulmonary valve and presents with right heart failure as 5-HT is metabolized by the lung. Left-sided valve involvement is quite rare. We describe our experience of 3 patients presenting with heart failure secondary to carcinoid heart disease affecting all four cardiac valves. There are only four previous isolated case reports in the literature.

METHODS

All three patients underwent quadruple valve replacement during a single operation. Right ventricular outflow tract reconstruction with a pericardial patch was performed in all patients. For 24 hours prior to surgery, all patients received intravenous octreotide, which continued in intensive care for at least 24 hours.

RESULTS

Mean cross-clamp and bypass times were 175 (range 164-197 minutes) and 210 (range 195-229 minutes) minutes, respectively. Mean intensive treatment unit (ITU) and inpatient stays were 2.3 (range 2-3 days) and 12 (range 9-16 days) days, respectively. One patient was reopened for bleeding 4 hours postoperatively from a ventricular pacing wire site. None required a permanent pacemaker postoperatively. There were no other complications in any patient. The quality of life was excellent at 6-16 months clinic follow-up as they were in NYHA 1. Postoperative echocardiography showed no paravalvular leaks and well-functioning prostheses in all cases.

CONCLUSION

Surgery to replace all four valves is feasible with excellent medium-term survival and a very low rate of complications. Patients with carcinoid heart disease should always be considered for surgery irrespective of the extent of valvular involvement.

Valvular Disorders in Carcinoid Heart Disease

Carcinoid heart disease is a rare but important cause of intrinsic right heart valve disorders leading to right heart failure. Occasionally, left-sided heart valves may also be involved. The characteristic cardiac pathological findings of carcinoid heart disease are endocardial thickening as a result of fibrous deposits on the endocardium. Echocardiographic examination and right heart catheterization are very useful for the diagnosis of the lesion. If more cardiac valves are affected, multiple valve replacement should be considered. The management of the pulmonary valve lesion depends on the extent of the diseased valve, either by valvulotomy, valvectomy, or valve replacement. Percutaneous valve implantations in the pulmonary and in the inferior vena cava positions have been advocated for high-risk patients.

New therapeutic approaches to metastatic gastroenteropancreatic neuroendocrine tumors: A glimpse into the future

Neuroendocrine (NE) gastroenteropancreatic tumors are a heterogeneous group of neoplasias arising from neuroendocrine cells of the embryological gut. Their incidence have increased significantly over the past 3 decades probably due to the improvements in imaging and diagnosis. The recent advances in molecular biology have translated into an expansion of therapeutic approaches to these patients. Somatostatin analogs, which initially were approved for control of hormonal syndromes, have recently been proven to inhibit tumor growth. Several new drugs such as antiangiogenics and others targeting mammalian target of rapamycin pathways have been approved to treat progressive pancreatic neuroendocrine tumors (NETs) although their role in non-pancreatic is still controversial. The treatment of NETs requires a coordinated multidisciplinary approach. The management of localized NETs primarily involves surgical resection followed by surveillance. However, the treatment of unresectable and/or metastatic disease may involve a combination of surgical resection, systemic therapy, and liver-directed therapies with the goal of alleviating symptoms of peptide release and controlling tumor growth. This article will review the current therapeutic strategies for metastatic gastroenteropancreatic NETs and will take a glimpse into the future approaches.

Surgical Treatment of NEN of Small Bowel: A Retrospective Analysis

BACKGROUND

Neuroendocrine Neoplasms of the small intestine have been noticed more frequently over the past 35 years. They constitute about 25% of all NENs and 29% of all tumors of the small intestine. Due to the predominantly indolent nature and overall good prognosis, the benefit of surgical treatment is still debated.

METHODS

In a retrospective study, data of 83 surgically treated patients with neuroendocrine neoplasms of the small intestine, 48 males and 35 females with a median age of 62 years (range 25-86 years) were analyzed. Patient data were documented in the MaDoc database for neuroendocrine tumors of the University Medical Center of Mainz. IBM SPSS Statistics 20 was used for statistical analysis. Kaplan-Meier survival curves and Log-Rank tests, censoring patients at the time of last follow-up, were used to compare the overall survival depending on potential prognostic factors (stage, grade, surgical treatment).

RESULTS

At the time of diagnoses, the most common clinical symptoms were abdominal pain (n = 31, 37.3%), bowel obstruction (n = 11, 13.3%), bowel perforation and peritonitis (n = 3, 3.6%), gastrointestinal bleeding (n = 9, 10.8%), weight loss (n = 11, 13.3%), and carcinoid syndrome (n = 27, 32.5%). 65 patients (78.3%) had lymph node metastasis and in 58 patients (69.9%) distant metastasis were present. Segmental bowel resection (44) was the most common surgical procedure, followed by right hemi-colectomy (32) and explorative laparotomy (7). In most patients (78.9%), lymphadenectomy (systematic/selective) was performed. The 5-year survival of patients who underwent a systematic or a selective lymphadenectomy differed significantly (82.2 vs. 40.0%). The overall 3-, 5-, and 10-year survival rates were 88.2, 80.3, and 71.0%, respectively.

CONCLUSION

Mesenteric lymph node metastases are almost invariably present and have significant impact on patients' prognosis. Systematic lymphadenectomy prevents complications and improves the survival. Early surgical treatment should be the goal in order to prevent complications.

Recurrent Peptic Ulcer due to Carcinoid Tumour of Jejunum

Carcinoid Tumours are classified as Neuro-endocrine tumours. Commonly known ulcerogenic neuro-endocrine tumour is Gastrinoma of the Pancreas and Duodenum.It secretes hormone Gastrin which causes hyperplasia of the gastric parietal cells with excessive secretion of hydrochloric acid resulting in multiple ulcerations in the stomach, duodenum and upper jejunum. Carcinoid tumours is not known to cause peptic ulceration.

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.

The impact of incidental identification on the stage at presentation of lower gastrointestinal carcinoids

BACKGROUND

Over the past 3 decades, there has been a significant increase in the incidence of gastrointestinal carcinoid tumors in the United States. Incidentally discovered carcinoids in the lower gastrointestinal tract have probably contributed to this increase. In this study we aimed to compare the clinicopathologic characteristics of incidentally discovered carcinoids of the small and large bowel with those identified as a result of symptoms.

STUDY DESIGN

We performed a retrospective review of 58 consecutive patients with nonappendiceal gastrointestinal carcinoids: 30 small bowel and 28 large bowel. We compared asymptomatic patients with lower gastrointestinal tract carcinoids identified by routine colonoscopy with those identified as a result of symptoms.

RESULTS

Twenty-eight (48.3%) incidentally identified carcinoids (15 small bowel and 13 large bowel) were compared with 30 (51.7%) symptomatic carcinoids. Incidental ileal carcinoids were similar in size (mean ± SD, 1.3 ± 0.61 vs 1.7 ± 1.13, p = 0.45) and incidence of lymph node metastases (12 in 15 vs 9 in 15, p = 0.43) to symptomatic ileal carcinoids. However, incidental ileal carcinoids had a lower incidence of distant metastases (1 in 15 vs 7 in 15, p = 0.035) compared with symptomatic ileal carcinoids. There was no difference in tumor size, extent of lymph node metastases, or distant metastases between incidental and symptomatic large bowel carcinoids.

CONCLUSIONS

Ileal carcinoids identified at screening colonoscopy are associated with a significantly decreased incidence of distant metastases compared with those identified after development of symptoms, despite similar size and extent of lymph node metastases. However, incidental large bowel carcinoids appear to have similar staging to those identified as a result of symptoms.

Management of neuroendocrine tumors: current and future therapies

Neuroendocrine tumors (NETs) are a genetically diverse group of malignancies that sometimes produce peptides that cause characteristic hormonal syndromes. NETs can be clinically symptomatic (functioning) or silent (nonfunctioning); 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 NETs is increasing. The primary treatment goal for patients with NETs is curative, with symptom control and the limitation of tumor 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 tumor growth and spread. Somatostatin analogues, such as octreotide long-acting repeatable (LAR), can improve the symptoms of carcinoid syndrome and stabilize tumor growth in many patients. Results from the placebo-controlled, double-blind, prospective randomized study on the effect of octreotide LAR in the control of tumor growth in patients with metastatic neuroendocrine midgut tumors (PROMID study) demonstrate that octreotide LAR 30 mg 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. Sunitinib, a tyrosine kinase inhibitor, is active in pancreatic NETs. In the future, pasireotide, the multireceptor targeted somatostatin analogue, has the potential to be an effective therapy for de novo or octreotide-refractory carcinoid syndrome and for inhibiting tumor cell proliferation. Peptide receptor radiotherapy with ⁹⁰Yttrium-DOTATOC or ¹⁷⁷Lutetium-DOTATE is also a new interesting treatment option for NETs.

Transannular pulmonary enlargement and bioprostheses for carcinoid disease

A diminutive pulmonary artery and right ventricular outflow tract in a 46-year-old woman with a 10-year history of carcinoid syndrome required transannular pulmonary patch enlargement to allow replacement of the pulmonary and tricuspid valves with bioprostheses. The avoidance of anticoagulation permitted further hepatic arterial embolization without an increased risk of bleeding.

Chronic subacute bowel obstruction caused by carcinoid tumour misdiagnosed as irritable bowel syndrome: a case report

Background

Carcinoid tumours are well-differentiated neuroendocrine tumours with secretory properties. Although fairly rare, they are the most common malignancy seen to affect the distal small bowel. Presentation is often non-specific with symptoms mimicking those of irritable bowel syndrome. Given this, the condition is often diagnosed late following disease progression, by which time the prognosis is poor.

Case presentation

A 74 year old Caucasian lady presented with a two week history of loose stools, nausea and one episode of vomiting. This sub-acute presentation occurred on a background of a four year history of intermittent abdominal pain and bloating, previously diagnosed as irritable bowel syndrome. CT scans identified dilated loops of small bowel proximal to a spiculated mass in the region of the terminal ileum. This ileal lesion was removed at laparotomy and identified as a carcinoid tumour.

Conclusion

This case highlights the issue of misdiagnosis of intestinal malignancy as the benign condition of irritable bowel syndrome. There have been several other references to this happenstance in the literature, and the problem is reflected in the percentage of patients with widespread disease at the time of diagnosis. Prognosis in this condition can be dramatically improved with early diagnosis, and surgical management at this stage is often curative. For this reason it is imperative to keep this differential diagnosis in the back of one's mind when assessing patients presenting with symptoms of intermittent partial bowel obstruction. The clinical presentation of this tumour, along with investigation and management of these cases, is discussed here.

Endoscopic resection of nonadenomatous ampullary neoplasms

The safety and effectiveness of endoscopic management of ampullary adenomas is well known. However, data on the endoscopic treatment and long-term outcome of nonadenomatous ampullary neoplasms are lacking. We describe our experience with the endoscopic management and the follow-up of 4 patients with nonadenomatous ampullary neoplasms viz, ampullary carcinoid, gangliocytic paraganglioma, ampullary hamartoma in patients with Peutz-Jegher syndrome and Cowdens syndrome.

Quadruple Valve Involvement in a Patient With Severe Carcinoid Heart Disease

We report on the case of a 48-year-old male patient suffering from a severe carcinoid heart disease with involvement of the four valves. The primary carcinoid tumor was diagnosed in the ileum. The patient developed a moderate stenosis and severe insufficiency of the tricuspid valve, a severe insufficiency of the pulmonary valve, and a moderate insufficiency of the mitral and aortic valves. Ultimately, a stentless pulmonary valve replacement was performed, as well as a tricuspid valve replacement with a pericardial prosthesis and aortic and mitral valve plasty. The patient recovered well and he was discharged from hospital on day 10.

Long-term survival of patients with small intestinal carcinoid tumors

Midgut carcinoid tumors are rare and have a markedly better prognosis than adenocarcinoma in the small intestine. New diagnostic methods and medical as well as surgical therapies have evolved during the last decades, leading to more active care of these patients. Patients with small intestinal carcinoids diagnosed from 1960 to 2000 in the duodenum (n = 89) and jejunum/ileum (n = 2437) were identified in the Swedish Cancer Registry. Cases without histologic verification and autopsy cases were excluded. Overall, cause-specific and relative survival were calculated. The overall 5-, 10-, and 15 year survivals were, respectively, 60%, 46%, and 28% for duodenal tumors and 56%, 36%, and 23% for jejunal/ileal tumors. Cause-specific 5-, 10-, and 15-year survival was 94% for all three follow-up periods for duodenal tumors and 87%, 80%, and 77% for those in the jejunum/ileum. The corresponding relative survivals were, respectively, 72%, 67%, and 51% for duodenal tumors and 67%, 54%, and 44% for those in the jejunum/ileum. Sex did not influence overall or cause-specific survival. The age at diagnosis correlated inversely with overall and cause-specific survival for tumors in the jejunum/ileum. For tumors in the jejunum/ileum, the overall and cause-specific survival correlated with the time period of diagnosis, with a more favorable prognosis for those diagnosed in recent years. A multivariate Cox proportional hazards model showed similar results. We concluded that young age and diagnosis in recent years are positive predictors of survival for patients with midgut carcinoids. The divergence between cause-specific and relative survival implies the need for a more detailed analysis of the causes of death of these patients.

Testicular metastasis of primary cecal carcinoid tumor

Testicular carcinoids are rare and the majority are of primary testicular origin. Testicular carcinoids can also be secondary from extra-testicular primary tumors, but the incidence is even less common. The case described here is a patient who initially had an infiltrating cecal carcinoid with hepatic metastasis. Following surgery, he was managed with octreotide and had close monitoring of the levels of serum serotonin and its urinary metabolite. He experienced a fairly indolent clinical course and 5 years after excision of the primary cecal carcinoid, his hepatic lesion has virtually been unchanged. However, he developed a secondary testicular metastasis. He has otherwise remained well, without evidence of metastases elsewhere on imaging studies.

Carcinoid--a comprehensive review

Carcinoid tumors originate from the neuroendocrine cells throughout the body and are capable of producing various peptides. Their clinical course is often indolent but can also be aggressive and resistant to therapy. We examined all aspects of carcinoid tumors including the molecular biology oncogenesis, role of angiogenesis, recent advances in imaging, and therapy. The Medline and Cancerlit databases were searched using carcinoid as the keyword. English language manuscripts were reviewed and relevant references from a total of 7741 were found. All titles were screened and all the relevant manuscripts were analyzed; we found 307 references pertinent to the history, epidemiology, clinical behavior, pathology, pathophysiology, molecular biology, radiologic imaging, supportive care of carcinoid syndrome, and results of therapeutic clinical trials. Management of patients with carcinoid tumors requires an understanding of the disease process and a multimodality approach. Introduction of long-acting somatostatin analogues has resulted in significant advances in the palliative care of patients with carcinoid syndrome. However, advanced carcinoid tumor remains incurable. Existing therapies for advanced disease have low biologic activity, high toxicity, or both. Clearly, more research is necessary in the areas of molecular biology, targeted therapy, and development of new drugs Future advances in this field need to focus on clinical and biological predictors of outcome. Early works in the area of tumor biology such as the role of p53, bcl-2, bax, MEN1, FGF TGF PDGF and VEGF expression are of interest and need to be explored further.

A 5-decade analysis of 13,715 carcinoid tumors

BACKGROUND

Carcinoid tumors represent an unusual and complex disease spectrum with protean clinical manifestations. This compilation of several large United States-based databases comprising patients from 1950 to 1999 examines 13,715 carcinoid tumors and provides epidemiologic information regarding the natural history and evolution of the detection and diagnosis of this entity.

METHODS

The authors evaluated 10,878 carcinoid tumors that were identified by the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute (NCI) from 1973 to 1999 in addition to 2837 carcinoid tumors that were registered previously by two earlier NCI programs. To the authors' knowledge, this represents the largest current epidemiology series addressing carcinoid tumors to date.

RESULTS

Specific trends in incidence for carcinoid tumors of certain sites were identified. Among the most recently collected subset of data, sites that demonstrated the greatest incidence of carcinoids were the gastrointestinal tract (67.5%) and the bronchopulmonary system (25.3%). Within the gastrointestinal tract, most carcinoid tumors occurred in the small intestine (41.8%), rectum (27.4%), and stomach (8.7%). For all sites, age-adjusted incidence rates were highest in black males (4.48 per 100,000 population per year). Associated noncarcinoid tumors were frequent in conjunction with small intestinal (29.0%), gastric (20.5%), colonic (20.0%), and appendiceal (18.2%) carcinoids. The highest percentages of nonlocalized lesions were noted for cecal (81.5-83.2%) and pancreatic (71.9-81.3%) carcinoids, whereas the highest percentage of localized disease was found among rectal (81.7%), gastric (67.5%), and bronchopulmonary (65.4%) carcinoids. The best 5-year survival rates were recorded for patients with rectal (88.3%), bronchopulmonary (73.5%), and appendiceal (71.0%) carcinoids; these tumors exhibited invasive growth or metastatic spread in 3.9%, 27.5%, and 38.8% of patients, respectively.

CONCLUSIONS

Carcinoids appear to have increased in overall incidence over the past 30 years; for some sites, this trend has been evident for nearly half a century. Recent marked increases in gastric and rectal carcinoids and a concomitant decrease in appendiceal carcinoid incidence may be due in part to varying rules of registration among the compiled databases examined in this report or to improvements in diagnostic technology; increased awareness of and about carcinoid tumors also may play a significant role. In 12.9% of all patients with carcinoid, distant metastases already were evident at the time of diagnosis; the overall 5-year survival rate for all carcinoid tumors, regardless of site, was 67.2%. These findings bring into question the widely promulgated relative benignity of carcinoid disease. Certain carcinoid tumors, such as those of the rectum, appear to be over-represented among the black and Asian populations within the United States, suggesting the role of genetics in the development of this intriguing disease.

Carcinoid heart disease: a case report and literature review

We report a patient who presented for elective exploratory laparotomy, and resection of a pelvic mass, which was thought to be ovarian carcinoma. Intraoperative transesophageal echocardiography demonstrated right-sided valvular heart lesions, which suggested the diagnosis of carcinoid syndrome before a pathologic confirmation was obtained. This article discusses the classical presentation and anesthetic management of patients with carcinoid syndrome and emphasizes the importance of proper preoperative diagnosis and careful planning if the incidence and severity of the symptoms that this condition can provoke are to be reduced.

The carcinoid syndrome: an unusual cause of valvular heart disease

A 30-year-old woman presented to the Emergency Department with complaints of shortness of breath, orthopnea, and a severe reduction in exercise tolerance. The symptoms were the result of severe valvular heart disease that resulted from a bronchopulmonary carcinoid tumor. The carcinoid syndrome is a distinctive clinical syndrome seen in patients with carcinoid tumors. Cardiac valvular lesions are seen in the majority of patients with the carcinoid syndrome and represent the most clinically significant consequence of the carcinoid syndrome. This case report discusses carcinoid tumors, the carcinoid syndrome induced by these tumors, and the therapeutic options in the management of carcinoid tumors.

Use of the somatostatin analogue octreotide acetate in the treatment of encephalopathy associated with carcinoid tumor. Case report

Carcinoid tumors may present in a variety of ways dependent on sites of disease and ectopic hormone secretion. This case report describes a patient having metastatic carcinoid tumor who developed encephalopathy of uncertain etiology. Treatment with the somatostatin analogue octreotide acetate resulted in dramatic improvement in his mental status. Several plausible mechanisms are discussed.

Cardiovascular complications of malignant carcinoid disease

Carcinoid tumors are endocrinologic malignancies often associated with a characteristic syndrome-the malignant carcinoid syndrome. Cardiovascular manifestations of this rare illness result from unique pathophysiologic characteristics, are associated with poor prognosis, and are difficult to treat medically. The hemodynamic consequences of this disease present unique management problems perioperatively. New pharmacologic and surgical therapies for malignant carcinoids have improved quality of life for patients to the extent that carcinoid heart disease now has more impact on morbidity and mortality rates. Cardiologists may be called on to diagnose and treat this rare cardiac disease. We review, for consulting cardiologists, the pathophysiologic characteristics, cardiovascular manifestations, and management of this disease.

Facial flushes and diarrhoea

Images

Carcinoid tumours

The use of long-acting and potent somatostatin analogues is a major advance in the management of carcinoid tumours. In addition to providing effective symptom relief in malignant carcinoid syndrome, octreotide can also be used for diagnostic purposes. Despite its expense, octreotide is the current agent of choice for the treatment of this condition while analogues with different receptor specificities and pharmacokinetics hold promise for the future. Gastric carcinoids have aroused interest because of their experimental association with chronic hypergastrinaemia, a condition now commonplace because of the widespread use of H2-blockers and proton-pump inhibitors. This subject is reviewed. The slow evolution of many tumours demands prolonged follow-up and the active use of a variety of palliative interventions. These include measures such as hepatic and cardiac surgery, which might be deemed inappropriate for patients with other types of metastatic malignancy. Interferons may have a role when first-line treatments have failed. Chemotherapy is, generally, of limited value.

An analysis of 8305 cases of carcinoid tumors

BACKGROUND

Carcinoid tumors are unusual and most reports are anecdotal or limited in number. A series of 2837 cases was published in 1975. No recent large series is available.

METHODS

The authors evaluated 5468 cases identified by the Surveillance, Epidemiology, and End Results (SEER) program of the National Cancer Institute (NCI) from 1973 to 1991 together with 2837 carcinoid cases previously registered by 2 earlier NCI programs. To the authors' knowledge, the 8305 carcinoid tumors analyzed represent the largest current epidemiology series to date.

RESULTS

The most frequent sites for carcinoids were the gastrointestinal (GI) tract (73.7%) and the bronchopulmonary system (25.1%). Within the GI tract, most occurred in the small bowel (28.7%), appendix (18.9%), and rectum (12.6%). For all sites, age-adjusted incidence rates were highest in African American males (2.12 per 100,000 population per year). Associated noncarcinoid tumors were frequent in conjunction with small intestinal (16.6%), appendiceal (14.6%), and colonic carcinoids (13.1%). The highest percentage of nonlocalized lesions were noted for pancreatic (76.1%), colonic (71.2%), and small intestinal carcinoids (70.7%) and this corresponded to their poor 5-year survival rates (34.1%, 41.6%, and 55.4%, respectively). The best 5-year survival rates were recorded for appendiceal (85.9%), bronchopulmonary (76.6%), and rectal carcinoids (72.2%). These exhibited invasive growth or metastatic spread in only 35.4%, 27.2%, and 14.2% of cases, respectively.

CONCLUSIONS

Carcinoids appear to have increased in incidence in the past 20 years. In part, this may be due to different surgical rules of the various registries, improved diagnostic technology, and increased awareness. A cumulative analysis of all types of carcinoid tumors in the SEER group indicates that in 45.3% metastases are already evident at the time of diagnosis. The overall 5-year survival rate of all carcinoid tumors regardless of site was 50.4% +/- 6.4%.

An analysis of 8305 cases of carcinoid tumors

BACKGROUND

Carcinoid tumors are unusual and most reports are anecdotal or limited in number. A series of 2837 cases was published in 1975. No recent large series is available.

METHODS

The authors evaluated 5468 cases identified by the Surveillance, Epidemiology, and End Results (SEER) program of the National Cancer Institute (NCI) from 1973 to 1991 together with 2837 carcinoid cases previously registered by 2 earlier NCI programs. To the authors' knowledge, the 8305 carcinoid tumors analyzed represent the largest current epidemiology series to date.

RESULTS

The most frequent sites for carcinoids were the gastrointestinal (GI) tract (73.7%) and the bronchopulmonary system (25.1%). Within the GI tract, most occurred in the small bowel (28.7%), appendix (18.9%), and rectum (12.6%). For all sites, age-adjusted incidence rates were highest in African American males (2.12 per 100,000 population per year). Associated noncarcinoid tumors were frequent in conjunction with small intestinal (16.6%), appendiceal (14.6%), and colonic carcinoids (13.1%). The highest percentage of nonlocalized lesions were noted for pancreatic (76.1%), colonic (71.2%), and small intestinal carcinoids (70.7%) and this corresponded to their poor 5-year survival rates (34.1%, 41.6%, and 55.4%, respectively). The best 5-year survival rates were recorded for appendiceal (85.9%), bronchopulmonary (76.6%), and rectal carcinoids (72.2%). These exhibited invasive growth or metastatic spread in only 35.4%, 27.2%, and 14.2% of cases, respectively.

CONCLUSIONS

Carcinoids appear to have increased in incidence in the past 20 years. In part, this may be due to different surgical rules of the various registries, improved diagnostic technology, and increased awareness. A cumulative analysis of all types of carcinoid tumors in the SEER group indicates that in 45.3% metastases are already evident at the time of diagnosis. The overall 5-year survival rate of all carcinoid tumors regardless of site was 50.4% +/- 6.4%.

Carcinoid Tumors of the Gut

BACKGROUND: Carcinoid tumors are the most frequently encountered endocrine tumors of the gastrointestinal tract. They are most often found in the appendix, although they can arise in any location of the gut. Carcinoid tumors may secrete a variety of bioactive substances, which can cause the complex of symptoms associated with the carcinoid syndrome. METHODS: The authors reviewed the pathology, clinical presentation, and management of carcinoid tumors with an emphasis on the surgical management. RESULTS: The primary treatment for a carcinoid tumor located anywhere in the gut is surgical. Those who have widely metastatic disease or who are anatomically unresectable may undergo cytoreductive surgical debulking and/or hepatic arterial embolization followed by palliation of symptoms with octreotide, the long-acting somatostatin analog. CONCLUSIONS: The prognosis for patients with carcinoid tumors that are fully resected is excellent. Those with hepatic metastases and the carcinoid syndrome have a less favorable prognosis.

Prognostic variables in patients with gastrointestinal carcinoid tumours

Prognostic variables in patients with gastrointestinal carcinoid tumour were studied with a view to identifying those most likely to benefit from aggressive therapy. A total of 188 patients were studied; the median follow-up of those surviving was 72 months. On univariate analysis variables of prognostic significance were sex (P < 0.01), site of the primary tumour (P < 0.01), depth of invasion (P < 0.001), tumour size (P < 0.005), presence of lymph node (P < 0.001) or liver (P < 0.001) metastases, mode of discovery (P < 0.001) and operative intent (P < 0.001). On multivariate analysis the variables independently predictive of death from disease were sex (women have a better prognosis) and presence of metastases at the time of diagnosis.