Post-Chemotherapy Monocytopenia as a Predictor of Chemotherapy – Induced Neutropenia in Breast Cancer Patients

Background: Chemotherapy-induced neutropenia (CIN) is chemotherapy’s most frequent myelosuppression effect. Previous studies have examined static prognostic factors to assess dynamic neutrophil changes in each cycle. This study focuses on postchemotherapy monocytopenia as a more dynamic predictor of CIN. This research aimed to know whether post-chemotherapy monocytopenia can be used as a predictor of CIN in breast cancer patients undergoing the chemotherapy cycle. Methods: This research used a prospective and a retrospective longitudinal cohort of breast cancer patients undergo a CAF regimen at Sanglah Hospital Denpasar. The research was conducted on 30 samples for three cycles (90 total cycles). Monocyte data is taken in the first week (days 4 to 9), and neutrophil data is taken in the second week (days 10 to 16). Results: From statistical analysis with interval data scale, we obtained that p 0.001 with Pearson correlation 0.613 for cycle 1, p 0.001 with Pearson correlation 0.611 for cycle 2, and p 0.003 with Pearson correlation 0.522 for cycle 3. Conclusions: In conclusion, post-chemotherapy monocytopenia can be used to predict the occurrence of chemotherapyinduced neutropenia (CIN) with the strongest positive correlation in the first cycle.