FRACTAL PATTERNS INSIDE CELLS CAN REVEAL BREAST CANCER, scientists at the Mount Sinai School of Medicine have successfully shown (Andrew Einstein, 212-241-5851, einstein@msvax.mssm.edu). Pathologists must traditionally detect breast cancer through subjective means by studying individual cells from suspicious tissue and checking for abnormal-looking cell shapes and features. Analyzing images of actual breast cells, the Mount Sinai researchers have looked within the cell nucleus to study the distribution of chromatin, DNA-protein compounds which contain the chromosomes in a cell. Like many other biological structures in nature, chromatin forms a fractal pattern; that is, the arrangement of chromatin looks similar over a range of size scales. Applying their technique to cells from 41 patients (22 of whom were known to have breast cancer through independent means) the researchers correctly diagnosed 39 out of 41 cases (95.1% success rate) in a blind study. They did this by measuring differences in lacunarity (the largeness of gaps between chromatin regions in the nucleus) and by detecting differences in fractal dimension (which describes how fully a fractal object fills up the space that it occupies) between benign and malignant cells. (Einstein et al., Physical Review Letters, 12 Jan 1998.)