經尿道雷射攝護腺剜除術後之營養不良性鈣化：病例報告

黎赫^1,2、黃君平¹、丁慧恭¹

國防醫學大學三軍總醫院外科部泌尿外科¹; 國軍左營總醫院岡山分院²

Dystrophic calcification following transurethral laser enucleation of the prostate: A case report

Ho Li^1,2, Chun‑Ping Huang¹, Hui-Kung Ding¹

Division of Urology, Department of Surgery, Tri‐Service General Hospital, National Defense Medical University, Taipei, Taiwan¹;

Division of Urology, Department of Surgery, Gangshan Branch of Zuoying Armed Forces General Hospital, Kaohsiung, Taiwan²

Introduction: Dystrophic calcification (DC) is characterized by the abnormal deposition of calcium salts in soft tissues, often at sites of prior injury or necrosis. While not uncommon in various tissues, DC within the prostatic resection cavity (PRC) following transurethral laser enucleation of the prostate (TULEP) is a relatively rare complication. This report describes a case of DC in a patient who underwent procedures for benign prostatic hyperplasia (BPH) and vesical stone highlights the potential challenges in managing this condition.

Case Presentation: A 68-year-old male presented with a history of BPH and severe lower urinary tract symptoms (LUTS), including difficulty in urination, frequency, urgency, and terminal dribbling for years, with the exacerbation of the symptoms in recent months. Digital rectal examination (DRE) showed rubbery, enlargement, without nodule of the prostate. Prostate specific antigen (PSA) level showed 4.851 ng/mL. Transrectal ultrasound (TRUS) revealed an enlarged prostate (73.3 ml) with few small cysts and calcifications. Intravenous urography (IVU) showed an ovoid radiopaque stone (size: about 2.8 cm) in the urinary bladder (Fig. 1).

Cystoscopy with laser lithotripsy for vesical stone was performed, evacuating with Ellick evacuator and leaving the residual calculi fragments minimally (Fig. 2). Transurethral vapoenucleation of the prostate with thulium laser (TULEP) for persistent LUTS was conducted smoothly after 10 weeks of the prior procedure. The surgical specimen weighed 53 grams and showed "nodular hyperplasia" on pathology.

Despite these interventions, the patient continued to experience urinary symptoms after TULEP. Therefore, cystoscopy performed 14 weeks after the TULEP revealed a residual prostate "with round shape (occupied about 70-80% of cystoscopic field)" and "many tiny stones coating on the prostate fossa"(Fig. 3). A bladder scan showed zero milliliters residual volume. The patient subsequently underwent cystoscopy and removal of prostatic fossa stones. The pain over perineum while sitting relieved significantly after the operation.

Discussion: This case shares similarities with other reported cases of DC after TURP. Zumstein et al. described a 59-year-old male who developed complete calcification of the prostatic resection cavity (PRC) five weeks after TURP, requiring multiple resections and ultimately resolving with cautious removal of calcifications to minimize tissue trauma. Similarly, Urushibara et al. reported a case of recurrent DC after bipolar TURP in a 77-year-old male, where complete resolution of DC was observed on CT imaging thirteen months after surgical removal of the calcification. While the exact mechanism of DC following TURP remains unclear, several hypotheses have been proposed, including urine stasis, foreign body reaction, surgical debris or foreign bodies acting as a nidus for calcification, coagulative necrosis, and urinary tract infection (UTI). In this particular case, the presence of "tiny stones coating on the prostate fossa" suggests that factors like urine stasis and potential foreign body reaction to prostatic tissue debris might have played a role in the development of DC.

Managing DC after TULEP can be challenging. While re-resection is an option, it can further damage the prostatic urethra and potentially worsen symptoms. As evidenced by this case and previous reports, a more conservative approach, such as gentle scraping of the calcifications to minimize trauma to the prostatic tissue, may be more effective in preventing recurrence.