PURPOSE: To obtain a substance which is separated from human female urine and which is reformed so that it can be used as a substitute of squamous cell carcinoma extracted from human cancer tissues or other human sources, and which is useful as a squamous cell carcinoma immunoreactive antigen for diagnosis of cancer.

CONSTITUTION: Human female urine is collected, immediately frozen, and then its necessary amt. is defrosted and filtered by using a filter having at least 0.8 μm trapping function and by using Celite (R) as a filtering assistant. The filtrate is concentrated to cut off the mol.wt. component of <1000 dalton in a concentrating device. The concentrate is subjected to dialysis with a phosphoric acid buffer soln. (pH=6.9) and filtered through a 0.45 μm filter. Then the concentrate is divided into fractions by column chromatography, and each fraction is measured by radio immunoassay using I125 marked squamous cell carcinoma antigen and antisquamous cell carcinoma antigen antibody to select the active fraction. Thus, the objective squamous cell carcinoma (SCC-like) substance modified so that it can be used as a substitute of squamous cell carcinoma extracted from human cancer tissue or other human source is obtd.