PEC‐PRO: A new prognostic score from a series of 87 patients with localized perivascular epithelioid cell neoplasms (PEComas) treated with curative intent.

Background: Perivascular epithelioid cell neoplasms (PEComas) encompass a heterogeneous family of mesenchymal tumors. Previously described clinicopathologic features aimed at distinguishing benign from malignant variants but lacked prognostic value. Methods: This retrospective analysis examined clinicopathologic data from patients who had localized PEComa across French Sarcoma Network centers. The authors analyzed 12 clinicopathologic features in a Cox proportional hazard framework to derive a multivariate prognostic risk model for event‐free survival (EFS). They built the PEComa prognostic score (PEC‐PRO), in which scores ranged from 0 to 5, based on the coefficients of the multivariate model. Three groups were identified: low risk (score = 0), intermediate risk (score = 1), and high risk (score ≥ 2). Results: Analyzing 87 patients who had a median 46‐month follow‐up (interquartile range, 20–74 months), the median EFS was 96.5 months (95% confidence interval [CI], 47.1 months to not applicable), with 2‐year and 5‐year EFS rates of 64.7% and 58%, respectively. The median overall survival was unreached, with 2‐year and 5‐year overall survival rates of 82.3% and 69.3%, respectively. The simplified Folpe classification did not correlate with EFS. Multivariate analysis identified three factors affecting EFS: positive surgical margins (hazard ratio [HR], 5.17; 95% CI, 1.65–16.24; p =.008), necrosis (HR, 3.94; 95% CI, 1.16–13.43; p =.030), and male sex (HR, 3.13; 95% CI, 1.19–8.27; p = 0.023). Four variables were retained in the prognostic model. Patients with low‐risk PEC‐PRO scores had a 2‐year EFS rate of 93.7% (95% CI, 83.8%–100.0%), those with intermediate‐risk PEC‐PRO scores had a 2‐year EFS rate of 67.4% (95% CI, 53.9%–80.9%), and those with high‐risk PEC‐PRO scores had a 2‐year EFS rate of 2.3% (95% CI, 0.0%–18.3%). Conclusions: The PEC‐PRO score reliably predicts the risk of postoperative recurrence in patients with localized PEComa. It has the potential to improve follow‐up strategies but requires validation in a prospective trial. By using a weighted combination of clinicopathologic features, the perivascular epithelioid cell neoplasm prognostic (PEC‐PRO) score identified three different prognostic groups, including a low risk (score = 0), an intermediate risk (score = 1), and a high risk (score ≥2) of recurrence. The PEC‐PRO score reliably predicts the recurrence risk in patients with localized perivascular epithelioid cell neoplasms and has the potential to improve follow‐up strategies and personalize adjuvant treatments. [ABSTRACT FROM AUTHOR]