Prostatic stromal tumor of uncertain malignant potential (STUMP) is a rare neoplasm originating from specialized prostatic stromal cells, characterized by broad histologic patterns and unpredictable clinical behavior. With an incidence below 1% of all prostatic tumors and significant morphological overlap with stromal sarcoma, STUMP has long lacked diagnostic and therapeutic consensus, posing persistent challenges in clinical practice.
This review systematically evaluated 84 pure STUMP cases, detailing clinical presentations, radiological features, anatomical distribution, and immunohistochemical profiles, while focusing on the association between initial treatment strategies and outcomes. The analysis revealed a mean age at diagnosis of 58.8 years, with lower urinary tract symptoms (39.3%) and urinary retention (29.8%) as the most common presentations. Immunohistochemically, vimentin and estrogen receptor were universally expressed, while CD34 positivity and Ki-67 expression helped differentiate STUMP from smooth muscle tumors and sarcoma.
Regarding management, 34.5% of patients were initially observed, while others underwent TURP or prostatectomy. During follow-up, 19 patients (22%) experienced disease progression; excluding prostatectomy cases, the recurrence rate rose to 34.5%. Notably, none of the patients who underwent radical, simple, or partial prostatectomy, or enucleation, experienced recurrence during a mean follow-up of 35.2 months. Among progressors, 89.5% required further intervention, most commonly repeat TURP, yet many continued to have persistent growth and symptomatic recurrence. In contrast, those who underwent prostatectomy after progression had no further events. The mean time to progression was 33.8 months, underscoring the need for long-term surveillance even in initially indolent cases.
In conclusion, despite its uncertain malignant potential, STUMP carries a tangible risk of progression and rare sarcomatous transformation. Complete surgical excision is recommended as the preferred strategy, particularly for younger patients or those with larger or rapidly growing tumors. Active surveillance may be considered in selected elderly or asymptomatic patients, but only with rigorous follow-up. Given the current evidence base limited to case reports, future multicenter registries are urgently needed to establish standardized diagnostic and management guidelines for this rare entity.
The work titled “Prostatic stromal tumors with uncertain malignant potential: A scoping review of clinical challenges and management strategies” was published in UroPrecision (published on November 11, 2025).
DOI:10.1002/uro2.70040