Overexpression of p53 In Distant Tissues Predicts Second Primary Tumor

Head And Neck Cancer

Date: 5/4/2001

2001 APR 27 - (NewsRx.com & NewsRx.net) -- by N.R. Saltmarsh, staff medical writer - Altered expression of p53 protein in epithelial tissues distant from the primary tumor may signal second primary carcinoma in head and neck cancer, researchers say.

Second primary carcinoma is distinct from recurrence of the primary tumor and is peculiar to head and neck cancer, said N. Homann and colleagues at the University of Heidelburg.

"Whether altered p53 expression in tumor-distant epithelia at the time of diagnosis is of clinical value as a biomarker for second primary carcinoma development has not been rigorously answered because of the lack of long-term follow-up studies involving a sufficiently large patient cohort," said Homann et al.

They studied frozen sections of tumor-distant epithelia from 105 head and neck cancer patients using immunohistochemistry and linked their findings to clinical follow-up in these patients after a median of 55 months.

Homann and team observed overexpression of p53 in the epithelia for 46.7% of patients, and it was independent of p53 expression in the primary tumor, and of the tumor site, stage, size, and grade.

p53 overexpression in these mucosa, but not in the primary tumors, was significantly associated with an increased incidence of second primary carcinomas, the researchers reported ("Overexpression of p53 in tumor-distant epithelia of head and neck cancer patients is associated with an increased incidence of second primary carcinoma," Clinical Cancer Research, 2001;7(2):290-296.

"IHC staining for p53 overexpression in tumor-distant epithelia provides a simple and rapid tool to identify head and neck cancer patients at increased risk of developing second primary tumors," concluded Homann et al.

"Because p53 overexpression in these epithelia in our patient cohort was specifically associated with second primary cancer but not with recurrences, at least a fraction of the second primary cancers appears to have resulted from genetic events in the mucosa ('field cancerization')."

The corresponding author for this study is F.X. Bosch, University of Heidelberg, Molecular Biology Laboratory, HNO Klin, Neuenheimerfild 400, D-69120 Heidelberg, Germany.

A search at www.NewsRx.net for the term "head and neck cancer genetics and genomics" returned 16 articles in two specialized reports.

Key points reported in this article include:

* Researchers evaluated whether altered p53 expression in tumor-distant epithelia at the time of diagnosis was of clinical value in predicting second primary carcinoma in head and neck cancer

* They observed overexpression of p53 in 46.7% at median follow-up of 55 months, which was independent of p53 status of the primary tumor and of the tumor site, size, stage, and grading

* At least some fraction of second primary tumors seems to have resulted from p53 overexpression in these epithelia

This article was prepared by Genomics & Genetics Weekly editors from staff and other reports.