Conditional survival among patients with carcinoma of the lung

Objective: One- and 5-year probabilities of survival or death change once a patient has already survived greater than or equal to 1 year after diagnos is. The current paper reports these probabilities for lung cancer patients according to histologic subtype, stage, and age at diagnosis. Methods: Cumulative observed survival rates were calculated and compared am ong 95,283 patients with histologically confirmed lung cancer (diagnosed fr om 1983 to 1992 and followed through 1995) by the life-table method using p opulation-based tumor registries participating in the Surveillance, Epidemi ology, and End Results (SEER) Program of the National Cancer Institute, On the basis of the cumulative survival estimates, we derived the probability of death in the next year, conditioned on having already survived to the st art of the year (annual hazards), and the probability of survival condition ed on having already survived greater than or equal to 1 year (conditional survival), These rates were reported according to histologic subtype, stage , and age groups. Results: At the time of diagnosis, annual hazard rates differ greatly among histologic subtypes. However, by 5 years after diagnosis, the rates become similar. Bronchioloalveolar carcinoma displays the lowest annual hazards a nd small-cell carcinoma displays the highest annual hazards, Stage-age subc ategories within histologic subtypes continue to show large differences in annual hazard rates. Five-year conditional survival probabilities are also reported, providing survival information that is consistent to that obtaine d from the annual hazards. Conclusions: One- and 5-year prognosis for lung cancer patients is influenc ed by years already survived and histology, stage, and age at diagnosis. An nual hazards and conditional survival provides useful and more relevant inf ormation than conventional survival estimates for patients and their physic ians. These statistics can be directly obtained from cumulative survival es timates and should be more widely reported.