The Prognosis And Prognostic Factors Of Radiotherapy For Patients With Small Cell Lung Cancer

Objective: To explore the prognosis and prognostic factors ofradiotherapy for patients with small cell lung cancer (SCLC).Methods: Between January2009and April2012,99patients with SCLCwere analyzed retrospectively. Seventy-four patients were male and25patients were female. Their age ranged from27to82years, and the medianage was57year. Seventy-three cases were in limited stage and26were inextensive stage. No patient received surgery. Seventy-three patients receivedthoracic radiotherapy plus chemotherapy, and26cases received chemotherapyalone. Possible prognostic factors such as gender, age, smoking history, weightloss, pleural effusion, NSE level, anemia, serum albumin, clinical stage,distant metastasis and treatment modality were evaluated. Univariate survivalanalysis was performed using the Kaplan-Meier method to determineassociations between overall survival rate(OS) and clinical factors, and COXproportional hazard model was used for multivariate survival analysis.Results:(1)The patients were followed up to February25,2013andfollow-up rate was100%.The1-,2-year overall survival rates for all thepatients were70.4%and28.6%respectively. The median survival time was17months.(2) Univariate survival analysis：The1-,2-year survival rates were49.4%,20.2%for the patients with age≥65years, and77.1%,31.4%forpatients with age<65years (P=0.037). The1-,2-years survival rates forpatients with weight loss were59.2%,17.4%and75.2%,33.1%for patientswithout weight loss (P=0.045). The1-,2-year survival rates were53.8%and7.2%for patients with pleural effusion and76.4%,35.9%for patients with nopleural effusion (P=0.008). The1-,2-year survival rates were58.8%,17.6%inpatients with anemia and72.8%,30.7%in patients without anemia (P=0.023).According to the blood sodium, the1-,2-years survival rates for patients with hyponatremia were63.6%,17.8%, and76.0%,37.8%for the patients withnormal blood sodium (P=0.008). The1-,2-year survival rates were63.3%,16.7%in the group with distant metastases and72.5%,32.3%in the groupwith no distant metastase（sP=0.039）.The1-,2-year survival rates were76.3%,32.2%for patients received thoracic radiotherapy plus chemotherapy, and53.8%,19.2%for patients received chemotherapy alone (P=0.014). Accordingto the radiation dose, patients were divided into two groups≥50Gy or<50Gy. The1,2-year survival rates were83.0%,33.9%and46.2%,23.1%(P=0.039) respectively in the two groups. The1-,2-year survival rates were96.3%,53.5%for patients with concurrent chemo-radiotherapy, while for thepatients with sequential chemoradiotherapy or alternative chemoradiotherapythe1-,2-year survival rates were64.2%,19.5%(P=0.019). Patient treatedwith chemo-radiotherapy were divided into early group and late group further.The1-,2-year survival rates were85.6%,36.8%and56.5%,23.7%(P=0.008)respectively. The1-,2-year survival rates were78.2%,34.3%for the patientsreceived≥4cycles of chemotherapy, and26.7%,6.7%for the patients received<4cycles of chemotherapy, and there was a statistical difference (P=0.000).The1-,2-year survival rates were84.2%,39.3%for the patients receivingsalvage treatment when disease progress, while for the patients withoutsalvage treatment were51.1%,13.6%(P=0.000). While gender, smokinghistory, serum NSE, albumin and stage showed no influence on the survival.(3) Multivariate analysis suggested that distant metastasis (P=0.026), thoracicradiotherapy (P=0.028), the number of chemotherapy cycles (P=0.001), andremedy treat (P=0.000) were the independent prognostic factors of OS.Conclusion:1.Age，weight loss，pleural effusion，anemia，hyponatremia，distant metastases，thoracic radiotherapy(TRT)，chemotherapy cycles，salvagetreatment are prognostic factors for patients with SCLC. Metastasis is anindependent unfavorable prognostic factor and thoracic radiotherapy, at leastfour chemotherapy cycles are independent favorable prognostic factor for OS.2.Radiation dose should be more than50Gy. Concurrent chemoradiotherapy isbetter than sequential chemoradiotherapy or alternative chemo-radiotherapy, and radiotherapy should intervene at early time.3.The patients with refractorydisease or relapse can benefit from suitable salvage treatment.