Causes of Low White Blood Cell Count

5. Radiation Therapy

Cancer itself can be a cause of a low white blood cell count, but so can the radiation therapy used to combat it. Radiation therapy uses beams of energy (usually X-rays or protons) to destroy cancer cells. This same energy can also destroy healthy cells, which can lead to a lower white blood cell count. Factors like the region being treated, the dose of radiation, and the frequency of treatment can influence the effects on the immune system. Normal cells can usually repair the damage caused by radiation therapy, but some patients require additional treatments to help increase the white blood cell count.

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