One of the major challenges in treatment of cancer, such as lymphoma, myeloma, leukaemia, bladder cancer, breast cancer, gastric cancer, esophagus cancer, head and neck cancer and skin cancer are to improve early detection rates. The present invention provides a use of an antibody or an antigen binding fragment thereof which binds specifically to LY75 in the manufacture of a medicament for the treatment of a cancer in which LY75 is expressed selected from the group consisting of lymphoma, myeloma, leukaemia, thyroid cancer, bladder cancer, breast cancer, gastric cancer, esophagus cancer, and head and neck cancer. The antibody or an antigen binding fragment is conjugated to a therapeutic moiety which may be a cytotoxic moiety or a radioactive isotope. The invention further provides a method of detecting, diagnosing and/or screening for or monitoring the progression of a cancer in which LY75 is expressed by detecting in an isolated biological sample the presence or level of LY75 and detecting a change in the level.
