To investigate the clinical significance of serum tRF-Lys-CTT expression levels in predicting postoperative recurrence in patients with lung adenocarcinoma.

A prospective study was conducted on 75 patients who underwent surgery for lung adenocarcinoma at our hospital between January 2022 and December 2023. Based on recurrence within one year post-surgery, patients were divided into an observation group with recurrence 31 cases and a control group without recurrence 44 cases. Clinical data, laboratory indicators, and chest CT imaging features were collected. Serum tRF-Lys-CTT expression levels were detected using real-time quantitative(PCR). Univariate and multivariate logistic regression analyses were performed to identify factors influencing postoperative recurrence, and receiver operating characteristic polymerase chain reaction(ROC) curves were plotted to evaluate the predictive value of individual indicators and their combination for recurrence.

The observation group had higher age, larger tumor diameter (3.53±0.48)cm, and higher proportions of stage Ⅱ18 cases(58.06%) and stage Ⅲa 4 cases(12.91%) disease compared to the control group age, tumor diameter(3.32±0.33) cm, stage Ⅱ 14 cases(31.82%), stage Ⅲa 3 cases(6.82%). The tRF-Lys-CTT expression level (1.68±0.43) in the observation group was significantly lower than that in the control group (2.37±0.71), (P<0.001). Multivariate analysis identified age (OR=1.170, 95%CI: 1.027~1.331) and tumor stage (OR=6.233, 95%CI: 1.694~22.934) as independent risk factors for postoperative recurrence, while tRF-Lys-CTT (OR=0.028, 95%CI: 0.004~0.202) was a protective factor. ROC curve analysis showed that the area under the curve (AUC) for tRF-Lys-CTT in predicting recurrence was 0.815, with a sensitivity of 74.19% and specificity of 82.82%. The combination of age, tumor stage, and tRF-Lys-CTT improved the AUC to 0.908, with a sensitivity of 77.42% and specificity of 90.91%, which was superior to any single indicator (P<0.05). After treatment, 75 patients were followed up in the outpatient department. Among them, 67 cases (89.33%) survived and 8 (10.67%) died.

Low serum expression of tRF-Lys-CTT is closely associated with postoperative recurrence in lung adenocarcinoma and serves as a protective factor. The combination of age, tumor stage, and tRF-Lys-CTT detection improves the prediction of postoperative recurrence in lung adenocarcinoma, facilitating early identification of high-risk patients and guiding individualized intervention.