Mucinous and Nonmucinous Appendiceal Adenocarcinomas: Different Clinicopathological Features but Similar Genetic Alterations

• Published in: Modern pathology Vol. 15; no. 6; pp. 599 - 605
• Main Authors: Kabbani, Wareef, Houlihan, Patrick S, Luthra, Rajayalaksh, Hamilton, Stanley R, Rashid, Asif
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-06-2002; Elsevier Limited
• Subjects: Adenocarcinoma; Adenocarcinoma - genetics; Adenocarcinoma - metabolism; Adenocarcinoma - pathology; Adenocarcinoma, Mucinous - genetics; Adenocarcinoma, Mucinous - metabolism; Adenocarcinoma, Mucinous - pathology; Adult; Aged; Appendiceal Neoplasms - genetics; Appendiceal Neoplasms - metabolism; Appendiceal Neoplasms - pathology; Appendix; Base Sequence; Cancer; DNA Mutational Analysis; DNA, Neoplasm - chemistry; DNA, Neoplasm - genetics; Female; Genes, ras - genetics; Humans; Immunohistochemistry; K-ras; Male; Medical prognosis; Microsatellite instability; Microsatellite Repeats; Middle Aged; Mutation; Mutation, Missense; p53; Pathology; Patients; Polymerase chain reaction; Survival Analysis; Tumor Suppressor Protein p53 - biosynthesis; Adenocarcinoma; Microsatellite instability; K-ras; Appendix; p53
• ISSN: 0893-3952; 1530-0285
• DOI: 10.1038/modpathol.3880572

The genetic alterations of appendiceal carcinomas have not been reported in detail. We studied the clinicopathological factors and genetic alterations including microsatellite instability, p53 overexpression, and mutations of the K-ras proto-oncogene of 30 appendiceal adenocarcinomas, consisting of 23 mucinous and 7 nonmucinous carcinomas. Sixteen (70%) mucinous carcinomas presented with pseudomyxoma peritonei, but 6 of 7 (86%) nonmucinous carcinomas presented with appendicitis (P = .002). All carcinomas were microsatellite stable, and p53 overexpression was present in only 1 of 30 (3%) carcinomas. K-ras mutation was present in 11 of 20 (55%) carcinomas, including 8 of 16 (50%) mucinous and 3 of 4 (75%) nonmucinous carcinomas. The mean survival of patients with mucinous carcinomas was 26 ± 19 months compared with 13 ± 9 months for patients with nonmucinous carcinomas (P = .0002). Our findings suggest that mucinous and nonmucinous carcinomas of appendix have similar genetic alterations, but different clinical presentation and prognosis.