Do elderly cancer patients achieve an adequate dose intensity in common clinical practice?

Elderly patients rarely receive adequate dose intensity (DI) using conventional regimens. Possible causes are improper patient assessment, the chemotherapy (CT) regimen chosen, the number and severity of comorbidities, patient compliance and physician experience. To explore this issue, DI was retrospectively analyzed in elderly patients treated with conventional CT regimens for advanced solid cancer.

Patients > or =69 years were evaluated. All patients had metastatic solid tumors. Comorbidities, performance status (PS), toxicities, number of CT cycles, dose reduction and discontinuation of treatment were recorded. Relative DI (RDI) was calculated and regressed against these parameters.

108 patients were eligible. The most frequent diagnoses were: lung, head-and-neck and colorectal cancer. In 48 patients (44%), their initially scheduled treatment was modified. Mean RDI was 79% (range 19-100%, SD 20.6). Grade 3/4 non-hematological and hematological toxicity occurred in 27 (35/130) and 8% of patients (11/130), respectively. In regression analysis, RDI was significantly associated with hematological toxicity. RDI affected response rate but not overall survival.

RDI is significantly affected by toxicity. These data suggest the importance of the treatment schedule and patient selection as predictorsof adequate treatment. Some non-ratable variables, however, might also play a role regarding the dose intensity delivered.