以會陰痛為初始症狀之前列腺神經內分泌腫瘤伴隨罕見轉移

孫浩議¹、莊梓昱^1,2、張彰琦^1,2、邱逸淳²、邱文祥²

¹臺北市立聯合醫院忠孝院區外科部泌尿科

²國立陽明交通大學醫學院

Perineal Pain as the Initial Symptom in a Case of Aggressive Prostate Neuroendocrine Tumor with Unusual Metastasis

Hao-Yi Sun ¹, Tzu-Yu Chuang ^1,2, Chang-Chi Chang ^1,2, Yi-Chun Chiu ², Allen W. Chiu ²

¹ Division of Urology, Department of Surgery, Zhongxiao Branch, Taipei City Hospital

² National Yang Ming Chiao Tung University, School of Medicine, Taipei, Taiwan

Introduction

Prostate cancer is commonly diagnosed as adenocarcinoma, yet a rare and aggressive form, neuroendocrine prostate cancer (NEPC), can emerge, often displaying resistance to androgen deprivation therapy and a poor prognosis. NEPC may manifest as small cell carcinoma or other neuroendocrine types, often accompanied by an atypical pattern of metastasis. This report discusses a 77-year-old man with prostate adenocarcinoma and NEPC, presenting initially with perineal pain that led to the discovery of advanced metastatic disease.

Case presentation

A 77-year-old man, with a history of hepatocellular carcinoma, presented with persistent perineal pain that was unresponsive to standard analgesics over two weeks. The pain sometimes radiated to both flanks and was accompanied by cold sweating. Initial evaluation, including a digital rectal examination and imaging, revealed a 38x33mm ill-defined mass between the prostate and urinary bladder, suggesting advanced prostate carcinoma with neuroendocrine differentiation. Biopsy confirmed high-grade adenocarcinoma (Gleason score 5+4=9) with neuroendocrine features, evidenced by positive Chromogranin and Synaptophysin markers. Despite a low PSA level, further imaging detected metastases in the mediastinum and right axillary lymph node. Biopsies of these locations confirmed the neuroendocrine component of the carcinoma, showing an unusual metastatic spread. After diagnosis, the patient began androgen deprivation therapy and radiotherapy. Despite these measures, metastasis continued to progress. Surgical excision was performed to remove the mediastinal tumor, while chemotherapy with Etoposide and Cisplatin led to improvement in the axillary lymph node metastasis. Additionally, the patient underwent procedures to manage complications from the primary pelvic mass, including stent placement to relieve hydronephrosis and address ureteral strictures. Although the neuroendocrine component of the tumor drove a particularly aggressive course, chemotherapy achieved a temporary reduction in metastatic lesion size.

Conclusion

This case illustrates the atypical clinical presentation of prostate neuroendocrine tumors, where perineal pain was the initial symptom, and demonstrates the aggressive nature of NEPC with unique metastasis to the mediastinum and axillary lymph nodes. Due to low PSA levels and resistance to standard therapies, NEPC presents diagnostic and treatment challenges, emphasizing the importance of comprehensive diagnostic strategies and targeted therapeutic approaches in managing this aggressive subtype of prostate cancer.