OBJECTIVES: To investigate the correlation between tumor stroma ratio (TSR) and survival in patients with alveolar soft part sarcoma (ASPS), and the application of apparent diffusion coefficient (ADC) histogram parameters in assessing TSR. METHODS: This retrospective study collected 61 patients from May 2015 to December 2018. TSR was classified as stroma-rich (low TSR) or stroma-poor (high TSR) based on histology. The correlation between TSR and clinicopathological characteristics was analyzed. Prognostic value for 5-year progression-free survival (5-PFS) and 5-year overall survival (5-OS) were assessed using Kaplan-Meier analysis, log-rank test, and Cox regression. Independent sample t-tests or Mann-Whitney U-test and receiver operating characteristic curve analysis examined TSR and ADC histogram parameters. RESULTS: Sixty-one patients met the inclusion criteria (mean age 25.5 ± 12.2 years
30 males, 31 females). Low TSR was significantly associated with lymph node metastasis (p = 0.048). In multivariate analysis, low TSR was an independent adverse prognostic factor for 5-PFS (hazard ratios [HR] and 95% = 10.456, 95% confidence intervals [CI]: 1.816-60.208, p = 0.009) and 5-OS (HR = 4.789, 95% CI: 1.164-19.708, p = 0.030). Significant differences were found in ADC CONCLUSION: TSR is an independent prognostic factor for PFS and OS in ASPS patients. ADC histogram parameters serve as imaging biomarkers for evaluating TSR. KEY POINTS: Question The prognostic value of TSR in ASPS remains unclear, with limited imaging biomarkers available for assessment. Findings Low TSR is associated with poorer 5-PFS and OS. ADC histogram parameters aid in TSR evaluation. Clinical relevance TSR as a prognostic factor, assessed through ADC histogram parameters, offers a non-invasive imaging method that may be useful in predicting the progression of alveolar soft tissue sarcoma.