[Toluidine blue staining in laryngeal diseases (author's transl)].

The authors present the results of 83 consecutive in vivo stainings with toluidine blue in various laryngeal diseases. Thirty one (86%) of the 36 malignant tumors showed positive staining. (95% confidence limits: 70-95.) It is concluded that malignant tumors will nearly always fix the dye, and that a negative staining test seems to be evidence against cancer. (Predictive value of negative test: 0.89, 95% confidence limits: 76-96.