Prostate cancer featuring a unique progression pattern: A case of prominent direct perineal invasion without definite metastasis.

Locally advanced prostate cancer can extend into the pelvis, and can also invade the bladder and rectum. We encountered a patient with prostate cancer that exhibited severe local invasion, protruding into the perineum. Distant metastasis was absent, despite the large tumor size. The tumor bled and caused difficulty sitting and standing, compromising the patient's quality of life. Total pelvic exenteration and chemotherapy were considered, but the patient's general condition rendered these therapies inappropriate. However, of the limited treatment options available given the patient's condition, palliative irradiation of the protruding region proved effective.