e12048 Background: Fatigue and insomnia are frequent conditions experienced by breast cancer patients during adjuvant radiation therapy (RT). Our group reported that fatigue correlates with reduced CD34+ circulating hematopoetic stem cell (HSC) levels. Our current study examined the role of inflammatory cytokines in mediating fatigue and insomnia following adjuvant RT. Methods: Phlebotomies were conducted on 148 breast cancer patients undergoing adjuvant RT at five time points: prior to RT (D1), after two (D2) and five (D5) days of treatment, during the final week of RT (Df), and one month post-RT completion (M1). CD34+, CD45+, circulating blood cell (CBC), and 17 inflammatory cytokine levels were assessed. Patients also completed questionnaires at each time point, including the multidimensional fatigue inventory (MIF-21), insomnia severity index (ISI), and hospital anxiety and depression scale (HADS). Results: CD34+, CD45+ and CBC levels decreased during treatment with adjuvant RT, with the lowest levels observed at Df (p<0.001). General fatigue significantly worsened throughout treatment from D1 to Df, returning to baseline at M1, (p<0.001; adjusted for insomnia, depression and anxiety). General fatigue worsened as CD34+ counts, hemoglobin and CBCs increased (p<0.001). Insomnia increased with reduced CD34+, CD45+ and CBCs (p<0.05). TGF-β1, MCP-1, MMP-2, IL-1ra and IFN-α2a cytokine expression varied throughout RT (p<0.01), most significantly at Df. Elevated MCP-1, TNF-RII and TNF-a levels correlated with worsening general fatigue, increased insomnia, and reduced activity and motivation (p<0.001). MMP-2 increased as IL-1ra, CD34+, CD45+ and CBC counts decreased (p<0.001). Further, the 52 patients who received prior adjuvant chemotherapy had elevated levels of fatigue, insomnia and anxiety, which correlated with high HSCs levels. Conclusions: Our findings demonstrate that fatigue and insomnia are associated with reduced HSCs and increased MCP-1, TNF-RII and TNF-a pro-inflammatory cytokines. This examination of the effect of RT on fatigue and insomnia is one of the most comprehensive longitudinal clinical evaluations of its kind.
186: Process Streamlining to Reduce Respiratory Variation in Visually Monitored Deep Inspiration Breath Hold Radiation Therapy for Breast Cancer Patients
