IL6 and neoplasm: The pathophysiological mechanism of NF is related to the release of pyrogenic cytokines, particularly interleukin-1, interleukin -6, tumor necrosis factor (TNF)-α, interferon, and other miscellaneous factors.[9] These cytokines stimulate the preoptic hypothalamus and induce the release of prostaglandin E2.[10] Subsequently, fever is caused by the disinhibition of presympathetic neurons in the brainstem owing to prostaglandin E2 binding in the preoptic hypothalamus.[11] The release of TNF-α from tumor necrotic tissue is also a pathophysiological mechanism of NF.