Large Variation Even Within One Cancer

Biliary tract carcinoma genetic sequencing and corresponding mutational oncogenic variation

(RxWiki News) The structure of the bile duct, buried inside the liver, is a particularly hard area to monitor. For this reason, treatment is extremely difficult as symptoms show up very late.

Only 10 percent of bile duct cancers are detected early enough for surgery, so chemotherapy remains the usual treatment.

New research analyzes the genetics of cancer in order to find the best pharmaceutical targets.

"Talk to your oncologist about their use of genetic sequencing."

A team from the Massachusetts General Hospital found that a quarter of tumors arising in the bile duct may have a unique genetic profile, and have begun work on isolating that profile for targeted pharmaceutical therapy.

Researchers were surprised to find that the most common genetic mutation was in a protein known as isocitrate dehydrogenase and have begun further investigation in the role of the genes, IDH1 and IDH2

This conclusion highlights the trend of developing individualized therapy in cancer patients, with 15 different mutations being found among this single type of bile duct tumor.

"Identifying this new and relatively common mutation in intrahepatic bile duct cancer may have significant implications for the diagnosis, prognosis and therapy of patients whose tumors harbor this mutation," says co-senior author Andrew Zhu, M.D., Ph.D., director of Liver Cancer Research at the MGH Cancer Center. 

The analysis of 287 tumors specifically looked for 130 different mutations in 15 different genes. For bile duct tumors, common changes were identified within a number of genes known to be associated with cancer. These genes are related to growth regulation and suppression.

With so many variations possible for a given type of cancer, the study underscores the importance of treating cancers with specific and highly expensive antibodies only after ensuring the appropriate target is valid in that patient's cancer.

The results were published in The Oncologist.

The authors of this research denied any financial conflict of interest.

Review Date: 
March 8, 2012