A scoring method for an anti-trop2 antibody-drug conjugate therapy

A method of treating cancer comprising administering to a cancer patient an antibody drug conjugate (ADC) comprising an ADC payload and an ADC antibody that targets a protein on a cancer cell, wherein the protein is calcium signal transducer trophoblast antigen 2 (TROP2), the method comprising:

• staining a tissue sample from the cancer patient immunohistochemically using a dye linked to a diagnostic antibody, wherein the diagnostic antibody binds to the protein on the cancer cells in the tissue sample;
• acquiring a digital image of the tissue sample;
• detecting cancer cells in the digital image;
• determining for each cancer cell a mean optical density of staining by the dye in the membrane of the cancer cell;
• determining for each cancer cell a mean optical density of staining by the dye in the cytoplasm of the cancer cell;
• computing a normalized membrane optical density (nmOD) for each cancer cell in the digital image;
• identifying each cancer cell as nmOD positive if the nmOD of the cancer cell is equal to or less than a nmOD threshold;
• and
• identifying the tissue sample as nmOD positive if the percentage of cancer cells that are nmOD positive is equal to or greater than a nmOD percentage threshold;
• wherein a therapy comprising the ADC is administered to the cancer patient if the tissue sample is nmOD positive.