Various forms of cancer (breast, colon, and lung) make up three of the top five most commonly misdiagnosed medical conditions. In one study, Johns Hopkins found a 1.4% error rate in pathology tests in patients referred for cancer treatment. Another study found that common procedures misdiagnosed prostate cancer in 6 out of 535 samples. Needless to say, the occurrences are not uncommon and the risks are always considerable.