Liquid crystal (L.C.) thermographic study of 105 women with abnormal breast characteristics was undertaken to evaluate the efficiency of L.C. thermography in breast cancer detection. Six general thermographic signs were noted to occur in breasts affected by breast cancer. These signs were derived from L.C. thermograms of 17 patients with histologically proven carcinoma. Detection of palpable malignancies with L.C. thermography had a true-positive rate of 82.3%. The false-positive rate was 13.6%, and only one of 17 histologically proven malignancies gave no thennographic signs of malignancy. Liquid crystal thennograms of 197 apparently healthy women with no breast abnormalities were classified according to pattern type. Six distinct thermal pattern types were characterized with 8 subgroups distinguishable in each of 3 vascular pattern groups. The L.C. pattern type was studied as a function of age, past pregnancies, previous lactation, use or non-use of oral contraceptives, and breast size. I n general, women under 30 years of age, women with several past pregnancies, women who had lactated more than 10 months' total lifetime, women using oral contraceptives, and women with large breasts had a greater occurence of the vascular patterns. Women with abnormal breast characteristics (n = 100) and known lesions (fibrocystic disease, fibroadenoma, or carcinoma) were classified according to L.C. thermal pattern type. As expected, women with malignant lesions had a higher percentage of the vascular thermal pattern types.
HERMOGRAPHY IS A GENERIC TERM APPLIED T to techniques employed to map a surface temperature pattern. Ideally, a thermographic technique should give a quantitative, instantaneous thermogram equivalent to the largest possible number of individual temperature measurements per unit area with a high degree of temperature sensitivity and optical resolution. Cholesteric liquid crystals have unusually high thermal sensitivity. When applied to a blackened surface, these materials give rise to iridescent colors, the