A case of rapidly progressing prostate cancer diagnosed 20 months after holmium laser enucleation of the prostate

A 65-year-old man presented for treatment of benign prostatic hyperplasia. His prostate volume was 50 cm³ and serum prostate-specific antigen was 1.93 ng/mL. Digital rectal examination showed no malignant nodules on the surface of the prostate. Holmium laser enucleation of the prostate was performed. The enucleated tissue was 21 g and pathological examination revealed no malignancy. Serum prostate-specific antigen had increased continuously to 6.38 ng/mL and prostate biopsy was performed 20 months after holmium laser enucleation of the prostate. Pathological examination confirmed an adenocarcinoma of the prostate with a Gleason score of 9 (4 + 5). Computed tomography and bone scintigraphy demonstrated multiple bone metastases and we made a diagnosis of prostate cancer, cT2aN0M1b. After 3 months on androgen deprivation therapy, he developed castration-resistant prostate cancer and died within 13 months after diagnosis of prostate cancer, despite receiving sequential therapy including enzalutamide, docetaxel and abiraterone. In our case, prostate-specific antigen was not measured until 13 months after holmium laser enucleation of the prostate, after which prostate-specific antigen rose from 1.93 to 4.09 ng/mL. This report provides an important implication of continuous monitoring of prostate-specific antigen after holmium laser enucleation of the prostate to detect prostate cancer early.