Significance of changes in serum LDH and HBDH in predicting the efficacy of first-line chemoimmunotherapy in small cell lung cancer.

e20107 Background: The aim of this retrospective cohort study was to investigate small-cell lung cancer (SCLC) patients' clinical correlates of lactate dehydrogenase (LDH) and α-hydroxybutyrate dehydrogenase (α-HBDH) before and after first-line chemoimmunotherapy and their correlation with one-year outcomes. Methods: This study retrospectively analyzed the data of 201 SCLC patients who received first-line chemoimmunotherapy from January 2020 to February 2023 at the Tumor Hospital of Shandong First Medical University. Data were collected on LDH and α-HBDH values and their changes from the initial values before standardized treatment, two months and four months from the start of treatment, and progression-free survival (PFS) time within 1 year. The respective clinical correlates of LDH and α-HBDH were analyzed using the Mann-Whitney U test and binary logistic regression. Spearman's correlation coefficient was used to analyze the correlation of LDH and α-HBDH with one-year PFS. Results: The correlation between the different subgroups and LDH and α-HBDH was analyzed using the Mann-Whitney U test. There was a significant effect of subgroup T and subgroup N on LDH and α-HBDH, and in subgroup M, brain metastases bone metastases and liver metastases had a significant effect; pre-treatment levels of LDH and α-HBDH were significantly higher in patients older than 65 years than in patients younger than or equal to 65 years. years of age. HBDH levels after 2 months of treatment were significantly higher in patients with immune myocarditis than in patients without immune myocarditis. Analysis of the respective correlates of LDH and α-HBDH by binary logistic regression also yielded a significant effect of N, immune myocarditis, and age on LDH and α-HBDH, echoing some of the above results. Spearman's correlation coefficient was used to analyze the correlation of LDH and α-HBDH with one-year PFS. there was a significant negative correlation between 4-month LDH, 2-month and 4-month α-HBDH, and one-year PFS. Conclusions: This study demonstrated that patients' TNM stage, age, and immune myocarditis were associated with LDH and α-HBDH levels, which are prognostic factors affecting PFS in patients with first-line chemoimmunotherapy for small-cell lung cancer (SCLC), and that high LDH and α-HBDH were associated with a shorter PFS, with an intervals ranging from suggestive of their importance in disease progression assessment and potential utility in guiding first-line treatment strategies. importance and potential utility in guiding first-line treatment strategies. Correlation of LDH and α-HBDH with PFS Spearman's correlation-detailed format. PFS M Median(P25, P75) LDH at 4 months Correlation coefficient -0.229** 208(175-239) HBDH at 2 months Correlation coefficient -0.204** 161(137-185) HBDH at 4months Correlation coefficient -0.227** 157(139-189)