Alterations of Hematological Index and Coagulation Profile during Radiation Therapy of Breast Cancer Patients

Abstract

There is little evidence guiding the timing and thresholds to be attained of pre- and post-

radiation therapy blood assessments. Several studies have shown significant differences between populations, emphasizing the need for population-specific appropriate times for blood tests to obtain hematological index as well as coagulation profile. This cross-sectional study sought to determine the appropriate length of time between the radiotherapy (RT) sessions of breast cancer patients attending the radiation therapy unit of Maha Vajiralongkorn Thanyaburi Hospital. The subjects were 135 patients with breast cancer who had undergone chemotherapy as pre-operative systemic therapy and post-operative radiation therapy of 45-50 Gy in 25 fractions over 5 weeks. Blood samples were collected from all patients before each RT session and one week after the last session. All blood samples were subjected to standard hematological analysis, reticulocyte count, and coagulogram. There were statistically significant reductions in the mean total white blood cell count, lymphocyte, and platelet count after 1-week post-irradi- ation compared to the baseline and continuous decline for nearly 5 weeks of RT sessions. Lym- phocytes were found to be more sensitive to RT than other blood components. No statistical differences were observed for hemoglobin, hematocrit, and reticulocyte count. RT led to statis- tically significant increases in PT, aPTT and INR values. There were no significant alterations in hematological index as well as coagulation profile in relation to patients’ age range. No patients experienced the day break in treatment. The findings demonstrated that irradiation affects white

blood cells and blood coagulation system. The current timeframe for blood tests may thus be safe, however, this practice may not be necessary. It is recommended that patients have a blood count taken prior to the beginning of treatment to see whether the blood has normal amounts of blood parameters and coagulogram. If they are normal, the weekly laboratory monitoring throughout the therapy session may not be required unless clinically indicated.