Serum lactate dehydrogenase levels predict the prognosis of patients with soft tissue sarcoma.

Several studies have reported the prognostic factors for soft tissue sarcoma. Although serum lactate dehydrogenase (LDH) levels are associated with poor prognosis in several types of cancer, their role in soft tissue sarcomas remains unclear. Therefore, the present study evaluated the association between serum LDH levels and the clinical characteristics and prognosis of soft tissue sarcoma. A total of 103 patients diagnosed with primary soft tissue sarcoma between 2003 and 2019 were retrospectively examined, and the association between serum LDH levels at the first visit and clinical characteristics were analysed. In high-grade soft tissue sarcoma, the association between survival and clinical characteristics, including stratified LDH levels, was also analysed. Serum LDH levels were stratified (>253 and ≤253 IU/l) according to the standard values used at our institution. High serum LDH levels were significantly associated with the presence of metastasis and histological grade (P<0.001 and 0.040, respectively). In both the univariate and multivariate analyses, disease-specific survival (DSS) was significantly worse in patients with high-grade soft tissue sarcoma and high serum LDH levels than in patients with normal serum LDH levels (univariate analysis: P=0.025; multivariate analysis: Hazard ratio, 4.60; 95% confidence interval, 1.16-18.2; P=0.030). In conclusion, high serum LDH levels at the first visit predicted the presence of distant metastasis, high histological grade and worse DSS in patients with high-grade soft tissue sarcoma. Therefore, in patients with high serum LDH levels at the first visit, these risks should be considered during pretreatment examinations and post-treatment follow-up.