Characteristics of patients with colo-rectal cancer and comorbid dementia

Abstract

panitumumab in this patient population, we conducted a retrospective review of elderly patients treated with these agents at Fox Chase Cancer Center (FCCC) between 2004 and 2010. Methods: Patients aged ≥65 with confirmed metastatic adenocarcinoma of the colon or rectum treated with cetuximab or panitumumab were included in the analysis. Patient demographics, disease characteristics, treatment drugs and duration, KRAS status and overall survival were recorded. Toxicity evaluation included review of common hematologic and non-hematologic toxicities seen with these agents. Results: A total of 117 patients were included; 99 received cetuximab and 18 received panitumumab therapy. The majority of patients were males (58.9%) with colon cancer (82%) and stage IV disease at presentation (50.5%). The median age at treatment initiation was 73 years (range: 65–86). Median overall survival was 2.64 years, and the median time on treatment was 70 days. Overall survival was similar among the different age groups evaluated (65–69, 69–73, 73–80, 80–90) and no correlation was found between increasing age at treatment initiation and treatment duration. Worse performance status at treatment initiation was associated with a shorter overall survival (p=0.013) and with shorter treatment duration (p=0.01). Most patients were treated prior to the incorporation of routine KRAS testing. Thus, KRAS status was available for 35 patients (29.7%), of whom 5 had KRAS mutant tumors. 65% of cetuximab and 44% of panitumumab treatments were given in combination with chemotherapy (i.e. irinotecan). Advanced age was associated with higher use of single agent anti-EGFR antibody therapy (p=0.0009). Most patients received these agents in the second line (35%) or third line (39%) setting. No correlation was found between age or performance status at treatment initiation and the line of therapy in which the drug was used. The incidence of any grade 3 or higher non-hematologic toxicity was 36% (34% for single agent and 38.3% for combination therapy). Common grade 3 or higher non-hematologic toxicities were hypomagnesemia— 17.1%, diarrhea—10.2%, and rash—9.4%. The incidence of any grade 3 or higher hematologic toxicity was 15.3% (6.8% for single agent and 20.5% for combination therapy) with anemia being the most common heme toxicity in both groups. Longer treatment duration and poor performance status at treatment initiation were associated with increased rates of grade 3 or higher hematologic or non-hematologic toxicity (pb0.0001 and p=0.011 respectively). Conclusions: Our data demonstrate that anti-EGFR agents can be safely used for treatment of older adults with mCRC, with toxicity profiles similar to those reported in large phase III studies of generally younger patients. Poor performance status at treatment initiation was associated with decreased overall survival and increased incidence of ≥grade 3 adverse events.