Abstract
Background: Since the introduction of oxaliplatin and irinotecan, they have been the mainstay chemotherapies in the fluorouracil-based regimens, FOLFOX, FOLFIRI, and FOLFOXIRI, used in the treatment of advanced and/or metastatic colorectal cancer (CRC). These regimens are effective and usually well-tolerated in patients. However, they have been associated with neutropenia in some patients. Objective: The aim of this study was to assess risk factors of chemotherapy-induced neutropenia associated with the regimens used in CRC patients. Methods: A retrospective analysis was conducted of all CRC patients 'records who had been treated with the aforementioned regimens between January 2016 and February 2019 at the oncology clinics in a tertiary referral hospital in Riyadh, Saudi Arabia. Results:A total of 136 patients treated with the standard CRC regimens were identified. The majority of CRC patients (63.2%) had stage IV with extensive metastases. Twenty-two patients (16.2%) had developed neutropenia. However, only 13 of the neutropenic patients (59.1%) had shown symptoms of infections or fever. Most neutropenia occurred between the third and the fourth cycle of the used regimen. A significant increase in neutropenia was found in females (p=0.0273) and in patients with stage IV (p=0.0378). However, 53 CRC patients (39.0%) who received filgrastim had shown a significantly lower incidence of neutropenia (p=0.0027). Conclusion: Despite the effectiveness of the CRC chemotherapy regimens, the risk of neutropenia is still considerably elevated. The use of granulocyte colony-stimulating factors such as filgrastim is an effective intervention to reduce neutropenia, hence infections, in high-risk CRC patients