|
21 April 2006
Cancer Treatment Methodology Wrongheaded, Says Study 
Researchers from the Washington University School of Medicine in St. Louis are suggesting that a tumor's anatomical location in the body may have no relevance as to how the cancer should be treated. Their study, in the Journal of Pathology, suggests that traditional cancer treatments - which have established different drug regimens for brain, prostate or ovarian cancer, for example - should eventually be replaced with therapies that use drugs deemed to be of highest benefit based on the tumor's pharmacologic profile. Thus, treatment would be determined by how each patient's tumor reacts to anticancer drugs, regardless of the tumor's location. The study, based on samples of eight different cancers (colon, breast, prostate, ovary, lung, brain, melanoma and lymphoma), measured the amounts of specific proteins known to influence the effect of irinotecan (an anticancer agent). Surprisingly, it was found that the protein levels that determine irinotecan's effectiveness were independent of the anatomical origin of the tumor. "This study is the first time the pathway for a drug's effect has been analyzed in tumors from different anatomical locations," said researcher Howard McLeod. "We've shown that drug effect is independent of where the tumor came from in the body. If further studies confirm that a tumor-specific approach is better than the current anatomical emphasis, oncologists may have to stop thinking of themselves as colon-cancer or breast-cancer specialists, and let the cancer tell them which drugs to use for each specific patient." If tumor response can't be predicted from anatomical location, McLeod believes doctors should start selecting treatments based on what genes and proteins can tell us about how the tumor will respond to a drug. "If we rely just on what has clinically been shown to work in some cases for a particular anatomically defined cancer, we may not initially choose the best therapy for the individual patient. And with advanced cancer, a patient may get only one shot at the right therapy - making the wrong choice could be deadly," he added. Currently, no chemotherapeutic drug has been successful in more than 50 percent of patients with advanced cancer. But McLeod thinks that instead of considering a drug that works only ten percent of the time a failure, it would be better to consider such a drug effective for one in ten tumors and to search for the agents among the current arsenal of chemotherapeutic drugs that will work for the rest. "We have more than 70 FDA-approved drugs that potentially could be useful for a particular tumor," McLeod said. "We are now working on methods that can be used to identify those drugs that will work for each patient's tumor." Source: Washington University School of Medicine
|
