Landscape of AJCC staging system: limitations and improvements for communication with patients

초록

Background The cancer stage, which is stratified according to the extent of disease progression by grouping similar results, can be used to inform patients their disease status. However, since it was originally introduced to exchange information between physicians, patients could have the unmet need to understand their current status and prognosis just while hearing a certain stage. Methods According to the 8th edition of AJCC staging system, we gathered the survival information of 13 common cancers related to death in Republic of Korea (excluding hematologic malignancy and brain tumor) from a large-scale population study. Survival probabilities of 3-years for each primary cancer according to stages II and III were extracted from the studies and averaged. The primary sites exceeding the 95% CI of the mean were indicated as better prognosis group, and others falling below 95% CI of the mean were judged as worse group. Results Of 24 and 27 sub-stages from 13 primary cancers in stage II and III, mean 3-year survival probability was 70.4% (95% CI 9.2%) and 55.9% (95% CI 9.8%), respectively. In stage II, breast, colon, kidney, prostate and HPV-positive oropharynx were discriminated as better group (88.6%, 95% CI 3.7%) and esophagus, gallbladder, bladder and pancreas had worse prognosis (41.6%, 95% CI 12.8%). In stage III, stage IIIA and IIIB of breast, prostate and colon, and HPV-positive oropharynx had better prognosis (82.8%, 95% CI 5.7%) and ovary (IIIC), lung (IIIB and IIIC), esophagus, gallbladder, bladder, and pancreas had worse prognosis(29.2%, 95% CI 6.6%). Conclusions The survival probability of same stage varied greatly depending on the primary sites. Simply presenting a certain stage to a patient not being aware of the general prognosis for primary site could lead to misunderstanding about the insight, so sufficient supplementary explanation would be always necessary in clinics and the alternative tool need to be explored.