Interepithelial antibodies reactive with autologous (human) and heterologous (monkey) prostatic tissue have been demonstrated by the method of indirect immunofluorescence in an eluate of carcinomatous prostatic tissue obtained at autopsy from a patient with metastatic adenocarcinoma of the prostate who exhibited remission of both his local prostatic malignancy and osteolytic lesions of the cervical spine following cryotherapy of his primary prostatic tumour. Elution of antibodies from malignant prostatic tissue provides evidence of a preliminary nature that prostatic tissue (tumor?)-specific or tumor-associated antigens are liberated into the circulation following cryotherapy of the human prostate and offers further support to previous studies suggestive of the role of immunologic processes in prostatic cancer.