e19562 Background: There are few prospective evaluation of toxicity and functional consequence of systemic chemotherapy in the elderly cancer patients, especially in Asian population. Methods: We prospectively enrolled elderly cancer patients aged ≥ 65 yrs, receiving systemic chemotherapy between July 2006 and February 2008 at a community-based university hospital. We conducted the baseline and follow-up CGA at the time of first response evaluation (after 2∼3months), and analyzed the changes in ECOG performance status, activities of daily living (ADL), Instrumental Activities of Daily Living (IADL), Mini-Mental State Examination (MMSE), Short form Geriatric Depression Scale (SGDS), and Mini-Nutritional Assessment (MNA). Frequency of significant toxicity, defined as grade 4 hematologic toxicity, febrile neutropenia, early treatment withdrawal and hospitalization ≥ 7 days due to toxicity, were assessed and association between significant toxicity and each CGA parameter was analyzed by ANCOVA. Results: Out of 65 patients enrolled, 38 patients (median age: 69.5, 65-80) completed both assessments. The median number of cycles given was 6 (range 1-12), and chemotherapy was for adjuvant (7), curative (3) and palliative intent (28; 20 first-line, 8 ≥second-line). The relative dose intensity of chemotherapy was 0.8 (0.52–1.11). Significant decline was observed in ECOG performance status (p = 0.01), ADL and IADL (p<0.001 and p = 0.003), mental health status (MMSE; p<0.001), and nutritional status (MNA; p<0.001) after chemotherapy. Significant toxicity occurred in 9 patients (23.7%). Decline in MNA was the only CGA profile associated with occurrence of significant toxicity (p = 0.006). Conclusions: Our pilot study suggested that Asian elderly patients can tolerate systemic chemotherapy with low frequency of significant toxicity. Significant decline of physical, mental, and nutritional function was observed after chemotherapy and decline in nutritional status was the only predictor of significant toxicity.The careful follow-up of CGA parameters, especially nutritional status could be used to predict tolerance in elderly cancer patients receiving systemic chemotherapy. No significant financial relationships to disclose.