CD44 and in situ carcinoma: In another method of detection observed by Li et al., they used flow-cytometric analysis to quantify CD44+/CD24− cells, a method that may be influenced by the content of fibrous tissue when used with tumor samples that need to be disintegrated and that does not allow a distinction of labeled invasive tumor cells from noncancerous breast epithelia or residual in situ carcinoma cells [26].