Chen Cheng, Zhu Ye-Han, Huang Jian-An
Department of Respiratory, The First Affiliated Hospital of Soochow University, Suzhou 215006, China.
J Cancer Res Ther. 2018 Jun;14(Supplement):S336-S340. doi: 10.4103/0973-1482.168994.
Lactate formation is upregulated in tumor cells by lactate dehydrogenase (LDH). High serum LDH level is linked to many malignancies with poorer survival, but tumor LDH has not been well investigated in small cell lung cancer (SCLC).
The study was performed in 120 cases of SCLC confirmed by pathological examination. The evaluation of treatment response to chemotherapy was based on response evaluation criteria in solid tumors criteria. The serum LDH levels were determined at diagnosis and follow-up visits. The distribution and differences in LDH change and the chemotherapeutic response rate was evaluated by using χ tests. Receiver operating characteristic curves were calculated to select the cut-off level of an increase in LDH indicating significant progression. The correlation of time of serum LDH normalization, time-to-progression (TTP), and overall survival (OS) were analyzed by Pearson correlation. Influence of increasing LDH on survival was calculated using the Kaplan-Meier method.
At diagnosis, significant differences in LDH levels were found between the groups with limited or extensive. In contrast to the limited-stage group, the extensive-stage group showed significantly decreased the level of LDH after the first-line chemotherapy. In patients whose diseases progressed, LDH levels were significantly higher in the last 1-month period preceding progression compared with the level at the progression. In the follow-up, we found that prolonging periods of serum LDH normalization were co-related to TTP and OS significantly. An increase in LDH by at least 51.5 U/L was found to be associated to a significantly higher probability of disease progression, and patients with initial increased LDH had a significantly reduced probability of survival.
LDH is validated for its potential usefulness as markers for monitoring treatment response in SCLC and also suitable for discriminating between disease and disease-free periods.
乳酸脱氢酶（LDH）可上调肿瘤细胞中乳酸的生成。血清LDH水平升高与多种恶性肿瘤相关，提示预后较差，但肿瘤LDH在小细胞肺癌（SCLC）中的研究尚不充分。
本研究纳入120例经病理检查确诊的SCLC患者。化疗疗效评估依据实体瘤疗效评价标准。在诊断及随访时测定血清LDH水平。采用χ²检验评估LDH变化及化疗有效率的分布和差异。绘制受试者工作特征曲线，以选择提示疾病显著进展的LDH升高临界值。采用Pearson相关分析血清LDH恢复正常的时间、疾病进展时间（TTP）和总生存期（OS）之间的相关性。采用Kaplan-Meier法计算LDH升高对生存的影响。
诊断时，局限期和广泛期患者的LDH水平存在显著差异。与局限期组相比，广泛期组一线化疗后LDH水平显著降低。疾病进展患者在进展前最后1个月的LDH水平显著高于进展时的水平。随访中发现，血清LDH恢复正常的时间延长与TTP和OS显著相关。LDH升高至少51.5 U/L与疾病进展的可能性显著增加相关，初始LDH升高的患者生存概率显著降低。
LDH被证实可作为监测SCLC治疗反应的潜在标志物，也适用于区分疾病期和无病期。
