Medline ® Abstracts for References 4-6
of 'Cancer of the appendix and pseudomyxoma peritonei'
Primary malignant neoplasms of the appendix: a population-based study from the surveillance, epidemiology and end-results program, 1973-1998.
McCusker ME, CotéTR, Clegg LX, Sobin LH
BACKGROUND: Cancer of the appendix is an uncommon disease that is rarely suspected rarely before surgery. Although several case series of these tumors have been published, little research has been anchored in population-based data on cancer of the appendix.
METHODS: This analysis included all actively followed cases of appendiceal neoplasms reported to the National Cancer Institute's Surveillance, Epidemiology and End-Results (SEER) program between 1973 and 1998. Tumors were classified as "colonic type" adenocarcinoma, mucinous adenocarcinoma, signet ring cell carcinoma, goblet cell carcinoid, and "malignant carcinoid" (SEER only collects data on carcinoids specifically classified as malignant). We compared incidence, overall survival and survival rates by extent of disease at diagnosis.
RESULTS: Between 1973 and 1998, 2117 appendiceal malignancies were reported to the SEER program, of which 1645 cases were included in the analysis. Age-adjusted incidence of cancer of the appendix was 0.12 cases per 1,000,000 people per year. Demographic characteristicsof patients with goblet cell carcinoid tumors were midway between those of patients with malignant carcinoid and all types of adenocarcinomas. After controlling for age and extent of disease at diagnosis, the overall survival rate for patients diagnosed between 1983 and 1997 (n = 1061) was significantly worse for those with signet ring cell carcinoma than for those with any other tumor type (P<0.01). In addition, overall survival rates were better for patients with malignant carcinoid (P = 0.01).
CONCLUSIONS: Demographic characteristics of patients with cancer of the appendix vary by histology. Except for signet ring cell carcinoma and malignant carcinoid, the extent of disease at time of diagnosis is a more important predictor of survival than histology.
Department of Epidemiology and Preventive Medicine, University of Maryland, Baltimore, Maryland 21201, USA. firstname.lastname@example.org
A 5-decade analysis of 13,715 carcinoid tumors.
Modlin IM, Lye KD, Kidd M
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.
Department of Surgery, Yale University School of Medicine, New Haven, Connecticut 06520-8062, USA. email@example.com
A retrospective analysis of 1570 appendiceal carcinoids.
Sandor A, Modlin IM
Am J Gastroenterol. 1998;93(3):422.
OBJECTIVE: Information about the management and outcome of appendiceal carcinoids is sparse, because few series comprise more than 100 cases. In this study we have analyzed the epidemiology of 1570 appendiceal carcinoids, to compare outcome with other gastrointestinal carcinoid tumors.
METHODS: We evaluated 1570 appendiceal carcinoids in a series of 8305 carcinoid tumors from the SEER, the End Results Group, and the Third National Cancer Survey programs of the National Cancer Institute over the time period 1950-1991.
RESULTS: Appendiceal carcinoids comprised 18.9% of all carcinoid tumors and exhibited a marked female predominance (M/F ratio: 0.47). Age-adjusted incidence rates were 1.7-fold higher in women compared to men. Appendiceal carcinoids present earlier (average age: 42.2 yr) than other gastrointestinal carcinoids (62.9 yr) or noncarcinoid appendiceal tumors (61.9 yr). At the time of diagnosis 35.4% were nonlocalized. The overall 5-yr survival for localized lesions was 94%, for regional invasion 84.6%, and for distant metastases 33.7%. The 5-yr survival of appendiceal carcinoids (85.9%) was the highest among all types of carcinoid tumors. In 14.6% noncarcinoidtumors at other sites were also evident.
CONCLUSION: The high relative incidence of carcinoid tumors in the appendix is still poorly understood. The good overall 5-yr survival rates of appendiceal carcinoids as opposed to other carcinoids represents either a different biological behavior, earlier diagnosis, or expeditious management (appendectomy). However, the increased likelihood of coexisting neoplasms and the not uncommon presentation of metastatic disease should warrant careful evaluation and postoperative follow-up of such lesions.
Gastric Surgical Pathobiology Research Group, Yale University School of Medicine, New Haven, Connecticut 06520-8062, USA.