What does cancer screening have to do with tomato growing?

Cancer screening is considered to be a major strategy for combatting cancer. The United States Preventive Services Task Force (USPSTF) recommends screening for five cancers, but the strength of evidence about the effectiveness of screening is limited. To gain insights into the efficacy of early detection requires prospective, blinded, placebo-controlled clinical trials with decades of follow-up and inclusion of millions of participants. Recently, Bretthauer et al. estimated lifetime gained with cancer screening tests by using a meta-analysis of 18 large randomized clinical trials which included more than two million subjects. They asked if cancer screening tests are saving lives and how much life is extended due to commonly used cancer screening tests. Colorectal cancer screening with sigmoidoscopy prolonged lifetime by 110 days, while fecal testing and mammography screening did not prolong life. A modest extension of 37 days was noted for prostate cancer screening with prostate-specific antigen testing and 107 days with lung cancer screening using computed tomography, but these estimates were not statistically significant. The authors concluded that current cancer screening strategies do not significantly prolong life. Based on these data, and the known biological behavior of some cancers, we hypothesized that the current strategies of treating cancer, after detection, could be modified to avoid the side effects of screening, which is a major determinant of the patient's overall survival.