The presence of extracellular circulating or cell-free RNA in biological fluids is becoming a
promising diagnostic tool for non invasive and cost effective cancer detection. Extracellular
RNA or miRNA as biological marker could be used either for the early detection and
diagnosis of the disease or as a marker of recurrence patterns and surveillance. In this
review article, we refer to the origin of the circulating extracellular RNA, we summarise the
data on the biological fluids (serum/plasma, saliva, urine, cerebrospinal fluid and bronchial …