Molecular detection of gene mutations and methylation abnormalities: applications in solid tumor diagnosis

As our knowledge of the genetic and epigenetic abnormalities initiating and contributing to tumorigenesis grows, so too does the scope for earlier detection of cancer in patients. This bears an immense potential impact on the clinical management of patients with or at risk of solid tumors, since arguably the greatest problem facing clinicians is late presentation. PCR-based tests have been developed to detect mutant or hypermethylated alleles in exfoliative material and plasma/serum, enabling risk-assessment and early detection programs. Although there are certain limitations, a number of studies have already demonstrated the feasibility and reliability of molecular screening in solid tumors, including colorectal and lung cancers and such molecular approaches may soon be used routinely to detect precursor lesions and early-stage cancer.