To the Editor.
—Is prostate cancer more like breast cancer or lung cancer? For reasons that are hard to fathom, Drs Collins and Barry1 feel that it is more like lung cancer. They dismiss the parallels between prostate cancer screening and breast cancer screening without comment and then focus on the flawed studies in lung cancer that failed to demonstrate a survival benefit.2 In doing so, they conveniently ignore 2 major flaws in their own logic. First is tumor biology. Prostate cancer is characterized by a slow, natural progression of the disease,3 whereas the clinical course of lung cancer is frequently established before it can be seen on x-ray examination. For example, by the time the diagnosis of small cell carcinoma of the lung is established, dissemination to distant organ sites has almost always occurred.4 In lung cancer studies, small cell cancer has comprised 25% of cases.2 This
Walsh PC. Is Prostate Cancer Screening Analogous to Lung Cancer Screening?. JAMA. 1997;277(14):1121. doi:10.1001/jama.1997.03540380035017