The retrospective evaluation of the effectiveness and tolerance of chemotherapy in elderly patient received adjuvant treatment with colorectal cancer

cancer (CRC) is the fourth most common cancer in the world and its incidence doubles every ten years between 40-80 years of age. Two-thirds of the patients are older than 65 years of age. In geriatric CRC patients, there is not much data on treatment selection, responses and toxicity. The aim of this study was to retrospectively evaluate the efficacy and tolerance of adjuvant chemotherapy in geriatric CRC patients who received adjuvant therapy. Between January / 2010-December / 2016, 236 patients aged 65 years who were admitted to Dokuz Eylül University Hospital Medical Oncology outpatient clinic were included in the study. 59.3% (140) of the patients were male and 40.7% (96) were female. 132 patients had colon cancer and 104 had rectal cancer. Regional lymph node involvement was present in 166 patients (70.3%). 74.6% (176) of the patients were given adjuvant therapy. There was statistically significant difference in the presence of node positivity and lymph-vascular invasion in patients receiving adjuvant therapy (p <0.001). The mean age was 73,56 (66-91), 73,4 (66-87) in the single agent treated group, 72,2 (66-85) in the combined treatment group and 75,8 (66-91) in the untreated group. . 33.9% (80) of the patients who received adjuvant therapy received single agent and 40.7% (96) of them received combined therapy. The most common adjuvant treatment protocols are; 27.5% (65) FOLFOX (Folinic asid + fluorouracil and oxaliplatin) , 16.9% (40) Capecitabine, 16.1% (38) 5-FU, 11% (26) XELOX (Capecitabine+ oxaliplatin). A statistically significant relationship was found between the FOLFOX regimen and hematological toxicities when the most common adjuvant treatment protocols were evaluated (p < 0.001). Non-hematological side effects were most frequently observed in FOLFOX and single agent Capecitabine regimens, while at least one agent was observed in the 5-FU regimen (p = 0.002). Non-hematologic side effects like diarrhea, hand-foot syndrome and fatigue were found to be significantly associated with Capecitabine regimen (p <0.001). Comorbid diseases observed in patients and decisive in dose reduction; 22% CHF, 19.9% CAD, 16.9% uncomplicated DM, 18.2% kidney failure. In the follow-up, 12 of the 236 patients (5.1%) had local recurrence; It was observed that 35 (14.8%) patients had metastasis. The mean follow-up period was 46 months (1-99.4), while 181 patients (76.7%) were observed to have a follow-up period. The mean age of patients receiving adjuvant therapy was 72.7 (66-87) years. 92 of them was Stage 0- 2C; 84 was Stage 3A- 3C. In Stage≥3A patients, combined treatment is preferred; Adjuvant treatment with single agent was found to be preferred in patients with Stage ≤ 2C (p <0.001). If we look at the overall survival rates (OS) of the patients; 84,3 ± 3,5 months (95% 77,4-91,3) in patients treated with single agent , 77,9 ± 3,2 months (95% 71,5-84,4) in patients treated with combined therapy , 66 9 ± 6 months (95%, 55-78, 7) in patients with no treatment (p = 0.014). Disease-free survival rates (DFS) of the patients included in the study were examined separately; 87.67 ± 3.3 months (95% Cl 81,13 - 94,22) in single-agent treatment , 77,31 ± 3,3 months (95% Cl 70,78 - 83,85) in combined treatment, 86,40 ± 4,6 months (%95Cl 77,42 - 95,45) in patients with no treatment (p = 0,412). As a result, there was no statistically significant difference between the groups receiving single agent therapy, combined treatment and not receiving treatment according to the adjuvant treatment status. In our study, the selection of treatment according to risk factors and comorbid diseases, the lack of significant OS and DFS differences in the statistical analysis among the treatment groups was attributed to the correct management of patients in terms of risk factors and treatment indication. Individual-specific, multidisciplinary and holistic approaches are important in the treatment planning of geriatric patients. It is important to ensure that appropriate age-matched treatment matches care objectives, and to make changes based on comorbidities and risk factors associated with the disease.