MUC5AC and mycosis fungoides: A recent study that investigated the possibility of distinguishing the premycotic stage MF (prediagnostic stage) from benign skin conditions based on histological criteria found that convoluted lymphocytes, subcutaneous infiltration, and follicular mucin are 100% specific for MF, and the absence of edema is 100% sensitive and a specific criterion for differentiating MF from inflammatory imitators [22,39].