Biomarkers needed to gauge passive smoke exposure

July 2, 2008

NEW YORK (Reuters Health) - Biological indicators, or "biomarkers" of exposure to secondhand smoke that can be analyzed in blood, tissue or other samples, or through imaging scans are needed to examine whether exposure to secondhand smoke may cause lung cancer.

That's the conclusion of the writers of a report in a special issue of The Lancet Oncology medical journal, which is dedicated to lung cancer.

Although numerous reports have linked exposure to secondhand smoke to lung cancer, the extent of the risk remains debatable, Dr. Ahmad Besaratina and Dr. Gerd P. Pfeifer, from the City of Hope National Medical Center in Duarte, California, note in their report.

Temporal variations in the concentration, composition and source of secondhand smoke make it difficult to gauge exposure, the researchers explain. Since lung cancer has a long latency period, the timing of secondhand smoke exposure is important.

In reviewing various human and laboratory studies, Besaratina and Pfeifer focused on the mechanisms by which secondhand smoke may contribute to the formation of lung cancer. A better understanding of these mechanisms, they contend, could help identify relevant biomarkers for assessing secondhand smoke exposure.

The report by Besaratina and Pfeifer will be presented at the International Lung Cancer Conference in Liverpool, UK, which gets underway July 9.