1. A method for detecting cancer or a precancerous condition from images collected from a population of cells present in a bodily fluid, comprising the steps of: (a) providing a first population of abnormal cells and a second population of normal cells, the abnormal cells comprising at least one type of cells selected from the group consisting of cancer cells and cancer precursor cells; (b) imaging the first population of cells in flow to collect first image data, and imaging the second population of cells in flow to collect second image data, such that the first and second image data for each cell in the respective populations of cells includes a plurality of simultaneously collected images, the plurality of simultaneously collected images for each cell comprising at least one of the following two types of images: (i) multispectral images; and (ii) multimodal images; (c) analyzing the first and second image data to identify at least one cell characteristic that can be measured using the first and second image data and that enables the abnormal cells to be distinguished from the normal cells; (d) collecting a bodily fluid comprising a third population of cells; (e) imaging the third population of cells in flow to collect third image data, such that the third image data for each cell includes a plurality of simultaneously collected images, the plurality of simultaneously collected images comprising at least one of the following two types of images: (i) multispectral images; and (ii) multimodal images; and (f) analyzing the third image data to determine if any abnormal cells are present in the third population, by determining if the at least one cell characteristic that enables the abnormal cells to be distinguished from the normal cells is present in the third image data, the presence of abnormal cells indicating the presence of cancer or a precancerous condition.