Fluorescamine as a cytochemical detection reagent for mammary carcinoma cells

Fluorescamine is a versatile reagent for the cytochemical demonstration of primary amino groups. Following pretreatment with formaldehyde, only certain "protected" amino groups will react with fluorescamine. In the present study we show that compounds containing such amino groups are abundant in mammary carcinoma cells but undetectable in normal mammary gland cells. Most cytologically benign breast lesions are devoid of cells containing these compounds. Although much work remains to be done, the fluorescamine technique, which is rapid and simple to perform, may offer some help in the distinction between normal and malignant cells of the mammary gland.