Reaching 5 years without a relapse is considered a significant milestone by many cancer patients, sometimes dubbed a 'cancerversary.' The importance attached to the 5-year mark originates from the evaluation of blood cancers in the 1930s. At the time, these cancers were frequently and rapidly lethal. Patients who managed to survive for 5 years could reasonably be considered cured. Over time, the 5-year criterion expanded to all other cancer types, although its applicability varies. For some cancers, the likelihood of a recurrence indeed drops drastically after 5, or even just 2 years without a relapse. For other cancer types, such as breast cancer, the probability of a recurrence does not decrease significantly, even after many disease-free years. However, even without strong statistical implications, reaching the 5-year milestone holds personal meaning for many cancer patients as an occasion for celebration or reflection.