支气管癌是男性和女性癌症相关死亡的主要原因。对于更好的预后，早期诊断和治疗至关重要。与印度情况相关的血清生物标志物如血清淀粉样蛋白（SAA）和细胞角蛋白 21-1（CYFRA 21-1）已显示出在这些病例的诊断中很有希望，但对其在印度情况下的作用的数据仍缺乏。本研究旨在测量不同类型的肺癌中的SAA和CYFRA 21-1水平，并将其与无肺癌患者进行比较。还旨在比较化疗前后这些生物标志物的值，并将其与治疗反应相关联。该研究是在昌迪加尔政府医学院肺部医学科进行的前瞻性病例对照研究。所有经组织学和/或细胞学证实的肺癌病例被纳入研究组，而肺癌以外的疾病患者组成了对照组。通过完整的病史和全面的临床检查评估了所有患者。采用夹心酶联免疫吸附法测量血液中的SAA和CYFRA 21-1水平。研究组患者定期随访，并在四个化疗周期后再次测量生物标志物。肿瘤对化疗的反应按照修改后的固体肿瘤研究评价标准进行评估。统计分析使用SPSS版本19.0进行。研究组和对照组各包括20名患者。声音嘶哑和咳血与肺癌患者显著相关（P = 0.001和P = 0.025）。在肺癌中，SAA超过8745ng/ml，CYFRA 21-1超过2.55ng/ml被用作肺癌的诊断生物标志物。CYFRA 21-1的血清水平在非小细胞肺癌（NSCLC）中明显升高，与肺部小细胞癌（SCLC）相比。与C1周期相比，C4周期化疗后，CYFRA 21-1的血清水平明显下降（P = 0.014）。SAA和CYFRA 21-1可能是肺癌有价值的诊断生物标志物。此外，CYFRA 21-1也可作为肺癌患者接受化疗的预后生物标志物，因为它在C4周期化疗后显著下降。它还可能是区分小细胞和非小细胞肺癌的潜在生物标志物。版权声明：© 2023国际应用和基础医学研究杂志。

Bronchogenic carcinoma is a leading cause of cancer-related death in men and women. Early diagnosis and treatment in these cases are essential for a better prognosis. Serum biomarkers such as serum amyloid A (SAA) and CYFRA 21-1 have generated encouraging results regarding their use in the diagnosis of these cases but data on their role in the Indian scenario are still lacking.The study aims to measure the levels of SAA and CYFRA 21-1 in various types of lung cancer and compare them with patients without lung cancer. It also aims to compare the values of these biomarkers before and after chemotherapy and correlate them with response to treatment.It was a prospective, case-control study conducted in the Department of Pulmonary Medicine, Government Medical College, Chandigarh. All histologically and/or cytologically proven lung cancer cases were included in the study group while patients with diseases other than lung cancer formed the control group. All patients were evaluated through a complete history and thorough clinical examination. Measurement of SAA and CYFRA 21-1 in blood was done by sandwich ELISA method. The patients in the study group were followed up regularly and the biomarkers were measured again after four cycles of chemotherapy. The response of tumors to chemotherapy was evaluated as per modified Response Evaluation Criteria in Solid Tumors criteria. The statistical analysis was carried out using SPSS version 19.0.The study group and control group included 20 patients each. Hoarseness of voice and hemoptysis were significantly associated with lung cancer patients (P = 0.001 and P = 0.025, respectively). Serum levels above 8745 ng/ml for SAA and 2.55 ng/ml for serum CYFRA 21-1 were used as diagnostic biomarker in lung cancer. The serum levels of CYFRA 21-1 were found to be significantly raised in nonsmall cell carcinoma (NSCLC) in comparison to SCLC of lung. There was a statistically significant decrease in the serum levels of CYFRA 21-1 in lung cancer patients on C4 cycle of chemotherapy in comparison to C1 cycle (P = 0.014).SAA and CYFRA 21-1 could be valuable diagnostic biomarkers in lung cancer. CYFRA 21-1, in addition, could also be used as prognostic biomarker in lung cancer patients undergoing chemotherapy as it showed significant decrease after C4-cycle of chemotherapy. It can also be a potential biomarker to differentiate small cell and NSCLC.Copyright: © 2023 International Journal of Applied and Basic Medical Research.