Two Cases of Neuroendocrine Transformation of Prostate Carcinoma in the Era of Expanding Therapeutic Options: Do the Increased Number of Available Treatments Translate Into Improved Patient Outcomes?

Neuroendocrine prostate cancer is an aggressive and increasingly recognized resistance phenotype arising in advanced prostate adenocarcinoma, particularly after prolonged androgen receptor-directed therapy. We describe two patients with metastatic prostate cancer who developed rapid clinical progression accompanied by disproportionately low prostate-specific antigen (PSA) levels, ultimately revealing transformation to neuroendocrine carcinoma. These cases highlight the diagnostic challenges associated with this entity, the importance of obtaining new tissue for histologic confirmation when radiologic progression diverges from biochemical markers, and the limited effectiveness of current therapeutic options. Overall, these cases emphasize the critical need for improved clinical recognition and for continued research into targeted therapeutic approaches capable of addressing this highly aggressive phenotype.