WHITE RIVER JUNCTION, Vt., Nov. 25 (UPI) -- U.S. and Norwegian researchers say they hope their findings prompt a debate on whether breast cancer tumors ever go away on their own without treatment.
In their article published Tuesday in the Archives of Internal Medicine, researchers said one type of cancer -- a rare childhood tumor -- found through screening sometimes spontaneously disappears and they want to learn whether the same phenomenon could happen with breast cancers found in mammograms, USA Today reported.
The authors admit their study doesn't provide a definitive answer. Their quest for an answer could be impossible since its unethical for physicians to leave breast cancers untreated, an editorial accompanying the article said.
Researchers compared the number of breast cancers found in more than 100,000 Norwegian women screened every two years with an approximately equal number who received one mammogram after six years.
The two strategies should have found about the same number of cancers, authors hypothesized. Yet doctors actually found 22 percent more breast cancers among the women who got more frequent mammograms.
The finding raises the possibility that mammograms found cancers that eventually went away and never needed to be treated, said co-author Dr. H. Gilbert Welch of the VA Outcomes Group in White River Junction, Vt. Other experts disputed the study's findings and note that mammograms and early detection have been proven to save lives.
