Effects of newly developed chemotherapy regimens, comorbidities, chemotherapy-related toxicities on the changing patterns of the leading causes of death in elderly patients with colorectal cancer
A partir des données des registres américains des cancers et de la base Medicare portant sur 69 718 patients âgés atteints d'un cancer colorectal diagnostiqué entre 1992 et 2009, cette étude de cohorte rétrospective analyse les effets des comorbidités, des toxicités médicamenteuses et des récentes chimiothérapies sur les causes de mortalité
Résumé en anglais
Context : Abundant evidences have shown that newly developed chemotherapy regimens improved 5-year survival rate of CRC patients over the past two decades. However, their impact on risk of death from leading causes among elderly patients is still poorly understood.
Objective : To assess the effect of newly developed chemotherapy regimens, comorbidities, and chemotherapy-related toxicities on cause-specific risk of death and their temporal patterns among elderly CRC patients.
Design, Setting, and Participants : A retrospective cohort study of 69,718 elderly CRC patients with their first primary tumors in 1992-2009, identified from the 12 areas of Surveillance, Epidemiology, and End Results-Medicare linked database with their Medicare claims up to 2010.Main outcome measures The 5-year cause-specific risk of deaths from leading causes.
Results : The leading causes of death among CRC patients were CRC, circulation disorders, and secondary cancers, which accounted for 51.4%, 25%, and 4.6% of all-cause death, respectively. Patients diagnosed in more recent diagnostic time periods were significantly less likely to die from CRC (period2: 5-year HR=0.94, 95%CI: 0.90-0.97; period3: 0.86, 0.83-0.90), circulation disorders (period2: 0.94, 0.88-1.00; period3: 0.80, 0.75-0.87), and more likely to die from secondary cancer (period3:1.42, 1.20-1.68) compared to those diagnosed in period-1. Charlson comorbidities index and the selected pre-existing comorbidities were significantly associated with increased 5-year risk of death from all three leading causes. Both haematological and gastric toxicity were associated with reduced risk of death from CRC and circulation disorders. The association between diagnostic time period and risk reduction in death from CRC depended on chemotherapy treatment (p<0.0001). Subgroup analyses showed that the chemotherapy-dependent significant risk reduction was seen in patients with stage II-III CRC, patients without comorbidities, and patients without toxicities (p<0.0001 for all).
Conclusion The newly developed chemotherapy regimens were associated with the decreased risk of mortality from CRC.
