We report a case of a patient with locally advanced prostate cancer who had only lymph node involvement without bone metastasis on F-18 FDG PET/CT.

A 62-year-old Korean male was admitted to our hospital due to dysuria. His PSA level on admission was 79.35 ng/mL. A transrectal ultrasound-guided prostate biopsy confirmed prostate cancer and his Gleason score was 10 (5+5). F-18 FDG PET/CT demonstrated a hypermetabolic mass lesion with SUVmax 7.0 in the prostate and hypermetabolism with SUVmax 4.7 of the abdominal and pelvic lymph nodes. Tc-99m HDP bone scan showed no significant bone metastasis. The patient underwent hormonal therapy for 9 months. Follow-up F-18 FDG PET/CT showed significantly reduced size and FDG uptake in the prostate and abdominal and pelvic lymph nodes. In this case, treatment monitoring with F-18 FDG PET/CT showed decreased mass size and FDG uptake in the prostate and abdominal and pelvic lymph nodes.

Prostate cancer is increasing in frequency in Korea. Among them, ductal adenocarcinoma (DCP) has a more aggressive and poor prognosis than acinar adenocarcinoma (ACP), despite its low incidence. Patients usually present with symptoms of lower urinary tract symptoms and hematuria due to increasing tumor mass within the lumen of the prostatic urethra, making diagnosis of DCP by the transrectal prostate biopsy difficult. DCP is often metastasized at the time of diagnosis. DCP is transferable to most other organs but the metastasis to the anterior urethra is rare. There is no doubt that localized DCP requires radical prostatectomy (RP) but the guidelines for adjuvant therapy after RP have not yet been established. Methods of the treatment are confounded by individual differences, and arriving at a consensus is challenging due to insufficient data. We report a case of DCP and urethral metastasis after RP, thus aiding in the determination of treatment guidelines.