Most colorectal cancers begin with polyps that, unless removed, can become cancerous over time. Sigmoidoscopy, a less expensive and time-consuming procedure, is generally recommended for those over the age of 50 with an average risk for colorectal cancer. This is the largest study to screen the entire colon for cancer in people without symptoms. It is also the first study to compare these two types of exams. The results need to be verified in women, since 97 percent of study participants were men.
Colonoscopy can identify a number of pre-cancerous polyps that sigmoidoscopy can miss.
This long-term European study evaluated treatment for tumors as large as five centimeters and found that breast conserving therapy was as effective as radical mastectomies for overall survival. The researchers did note that patients who had breast conserving therapy had larger numbers of cancer recurring in the breast or nearby, but that these recurrences did not cause a difference in overall survival. This trial was the longest study of women with breast tumors that were up to 5 centimeters. Different centers in the trial may not have used the same criteria for selection of patients and may have had slightly different variations in treatment techniques. Breast conserving therapy is as effective as radified mastectomy in treating tumors that are up to five centimeters in size.