Key points from article :
Common and cheap painkillers boost survival rates if cancer contains one specific gene.
Crucial gene found in about one-third of head and neck cancers.
Ibuprofen and aspirin boosted survival rates from 25 per cent to 78 per cent .
Head and neck cancers are diagnosed in about 12,000 people in Britain each year.
University of California San Francisco studied survival rates five years after diagnosis.
The study was published in the Journal of Experimental Medicine.