To print: Select File and then Print from your browser's menu --------------------------------------------------------------------------------------- Title: AAO-HNSF: Cyclooxygenase-2 Over-Expression Found in Nasopharyngeal Carcinoma URL: http://www.pslgroup.com/dg/21EB22.htm Doctor's Guide September 25, 2002
By Paula Moyer Special to DG News SAN DIEGO, CA -- September 25, 2002 -- Cyclooxygenase-2 (COX-2) is over-expressed in the tumours of most patients with undifferentiated nasopharyngeal carcinoma. The finding is consistent with other data, which has shown COX-2 over-expression in other malignancies, such as colorectal cancer. Dr. Luke Kim-Sian Tan, associate professor of otolarynogology at the National University of Singapore, and Dr. Woei Shyang Loh, MD, chief resident of otolaryngology, presented findings at the 106th annual meeting of the American Academy of Otolaryngology-Head and Neck Surgery Foundation. "Most undifferentiated nasopharyngeal carcinoma tumours in our research showed over-expression of COX-2," said Dr. Tan. "Therefore, we need to look further into the role of COX-2 in these tumours." COX-2 is of interest in cancer research for many reasons, including its roles in angiogenesis and in the possible suppression of apoptosis, he said. The researchers sought to establish the level of expression of COX-2 in undifferentiated nasopharyngeal carcinoma (UC) (WHO type IIb), as well as the prognostic value of the enzyme in such tumours. They collected the data prospectively in 2000 and 2001 from the tumour tissues of 39 patients. After the tissues underwent immunochemical staining, the investigators graded the expression of COX-2 in the tumours and correlated it with tumour stage by using the Fisher exact test. Most patients had stage III or IV tumours with no distal metastases. Among the 39 specimens, 20 (51 percent) demonstrated over-expression of COX-2. Among those with stage III or IV, 62 percent showed over-expression of COX-2, a significantly higher number than those with stage I or II tumours (p<.05). "The rate of over-expression is lower than has been reported in other malignancies," said Dr. Loh. He said that the correlation with tumour stage was only true for global staging, and not for the various staging components such as nodal involvement. "The staging system for undifferentiated nasopharyngeal carcinoma is different from that for squamous cell carcinoma of the nasopharynx and from staging for several other malignancies," said Dr. Tan. "Size, for example, plays no role. Instead, the staging is dependent on the involvement of surrounding structures. Stage TIII, for example, indicates bone involvement, and Stage TIV indicates intracranial involvement. Nodal staging for undifferentiated carcinoma is different from squamous cell staging as well, because the size of lymph nodes are not considered N1 until they are beyond 6 cm in size. The whole behaviour of undifferentiated carcinoma is different from squamous cell tumours. Therefore, I'm not surprised that the T and N stages don't correlate well to COX-2 over-expression." Dr. Tan and his colleagues are next planning a translational trial, in which patients with nasopharyngeal cancer will receive COX-2 inhibitor treatment, in order to determine whether these medications have a role in the treatment of such tumours. No manufacturer of COX-2 inhibitors funded the presented research, and none is being sought for the translational trial, he said. --------------------------------------------------------------------------------------------- Copyright © 1999 P\S\L Consulting Group Inc. All rights reserved. Republication or redistribution of P\S\L content is expressly prohibited without the prior written consent of P\S\L. P\S\L shall not be liable for any errors, omissions or delays in this content or any other content on its sites, newsletters or other publications, nor for any decisions or actions taken in reliance on such content. --------------------------------------------------------------------------------------------- This news story was printed from *Doctor's Guide to the Internet* located at http://www.docguide.com --------------------------------------------------------------------------------------- Return to News Story Page This site is maintained by webmaster@pslgroup.com Please contact us with any comments, problems or bugs. All contents Copyright (c) 1998 P\S\L Consulting Group Inc. All rights reserved.