Successful management of prostate cancer with bulky pelvic lymph node metastases after rapid development of castration-resistant prostate cancer: a case report with review of the literature.

The rapid development of castration-resistant prostate cancer (CRPC) is a poor prognostic sign for loco-regionally advanced prostate cancer. Non-metastatic CRPC (nmCRPC) with bulky regional lymph node metastases is extremely rare and difficult to treat clinically without reported case. We present a case of a 72-year-old man with locally advanced prostate cancer with bulky lymph node metastases (53 mm × 77 mm × 67 mm), developing nmCRPC after 9-month ADT treatment. Immunohistochemistry (IHC) tests found partially positive MUC1 and negative BRCA1 expression in the initial biopsy specimens. Next-generation sequence analysis on the blood specimen after CRPC predicted a good tolerance to docetaxel. According to the multidisciplinary team recommendations, he was administrated docetaxel 75 mg/m2 on day 1 every 21 days for 6 cycles, and subsequently radiotherapy, with the delivery of a total dose of 67.5, 60-65 and 47.5 Gy in 25 fractions to the prostate, the enlarged lymph nodes and the whole pelvis respectively. Over a follow-up of 50 months, his disease has achieved good local control and he is alive without evidence of distant metastases or late adverse events. This case highlights individualized and multimodal therapy of intensification of systemic therapy and timely application of radiotherapy in such rare condition.