Outcomes and prognostic factors of chemotherapy for patients with locally advanced or metastatic pulmonary squamous cell carcinoma

BACKGROUND Pulmonary squamous cell carcinoma has not benefited from improvements in chemotherapy over the past decade, compared with non-squamous non-small-cell lung cancer. Nowadays, treatment strategies differ between squamous and non-squamous non-small-cell lung cancers. This study aimed to investigate the percentage of patients treated with first-, second-, or third-line chemotherapy and the characteristics of patients for whom chemotherapy has been beneficial. METHOD Data on patients with stage IIIB or IV squamous cell carcinoma diagnosed between June 2007 and March 2015, and on patients who had received first-, second-, or third-line chemotherapy between June 2007 and November 2015 at our hospital, were retrospectively extracted from our institutional medical charts. We also compared patients who were treated with chemotherapy (chemotherapy group) and patients who were not (non-chemotherapy group) using multivariate logistic regression and multivariate Cox hazard analyses, respectively. RESULTS During the study period, 103, 63, and 32 patients received first-, second-, and third-line chemotherapy, respectively. Fifty-one patients did not receive chemotherapy. Factors predicting unlikely chemotherapy included age ≥75 years, Eastern Cooperative Oncology Group (ECOG)-performance status (PS) ≥2, Charlson comorbidity index ≥2, hemoglobin <12.2 g/dL, red cell distribution width ≥13.9%, and serum sodium <140 mEq/L. Factors predicting survival for each line of chemotherapy included the following: ECOG-PS ≥2 for first-line; ECOG-PS ≥2 and lymphocyte count for second-line; and ECOG-PS ≥2, body mass index <18.5 kg/m2, and hemoglobin and lactate dehydrogenase levels for third-line. CONCLUSION Approximately 66% of patients received first-line chemotherapy. Of those, 66% and 33% received second- and third-line chemotherapy, respectively. ECOG-PS was always an essential prognostic factor when considering introducing chemotherapy and proceeding with additional chemotherapy. Other markers, such as lymphocyte count, body mass index, anemia, and lactate dehydrogenase level, may be useful depending on the patient and line of chemotherapy.