Clinical Heterogeneity and Survival Disparities in Leiomyosarcoma: An Exploratory Single-Center Retrospective Observational Study

Background: Leiomyosarcoma (LMS) is a rare aggressive sarcoma characterized by substantial heterogeneity in anatomical presentation, stage, metastatic pattern, therapy, and survival. Differences in outcome between anatomical sites may reflect both biological variation and differences in stage at presentation. We evaluated the clinical profile, treatment patterns, and survival outcomes of patients with LMS, with particular emphasis on whether anatomical site independently predicted survival outcomes. Methods: We conducted a retrospective review of adults with histologically confirmed LMS diagnosed between Jan ‘15 and May ‘26. Overall survival (OS) was calculated from the date of diagnosis to death from any cause or last contact, with censoring on 1 July ‘26. Kaplan-Meier methods and log-rank tests were used for survival comparisons. Multivariable Cox proportional-hazards models were used to assess whether primary site remained independently associated with OS. Results: Among 240 evaluable patients, median age was 56 years (range, 27–86), and 152 (63.3%) were female. Disease status was localized in 120 (50%), de novo metastatic in 53 (22.1%), recurrent metastatic in 35 (14.6%), and recurrent localized in 12 (5.0%); 20 (8.3%) were not classifiable by stage. Primary sites were extremity/trunk (27.9%), uterus (22.9%), retroperitoneum (22.5%), non-uterine abdomen (20.8%), and head and neck (5.4%). Median OS was 37.0 months (95% CI, 26.0–48.0). Patients with localized disease had substantially longer OS than those with metastatic disease (61.0 months [95% CI, 43.9–78.1] vs 13.0 months [95% CI, 10.2–15.8]; P<.001). Patients aged ≥50 years had shorter OS than those aged <50 years (28.0 vs 51.0 months; P=.017). In multivariable Cox models adjusted for sex, age group, and stage, metastatic disease remained strongly associated with inferior OS Neither non-extremity versus extremity/trunk disease nor uterine versus non-uterine disease remained independently associated with OS. Conclusion: LMS demonstrates marked variability in clinical presentation and treatment. Disease stage was the strongest independent prognostic factor, with metastatic disease associated with approximately fivefold higher mortality than early/localized disease. Older age was also independently associated with inferior survival. Although extremity/trunk primaries were associated with longer OS in univariable analysis, anatomical site was not independently associated with survival after adjustment for age, sex, and stage.