Efficacy of 3D conformal thoracic radiotherapy for extensive-stage small-cell lung cancer: A retrospective study

Abstract

Abstract. The aim of the present study was to evaluate the effect of 3-dimensional conformal thoracic radiotherapy (TRT) on extensive-stage small-cell lung cancer (ES-SCLC). A total of 165 patients with ES-SCLC were enrolled in the present study, including 82 patients receiving chemotherapy combined with TRT (the ChT/TRT group) and 83 patients receiving chemotherapy alone (the ChT group). The overall survival (OS) and progression-free survival (PFS) rates were compared between the ChT/TRT and ChT groups, and the prognostic factors for OS rate were identified. It was found that the patients had a median OS time of 15 months, and 2-and 5-year OS rates of 31.5 and 2.4%, respectively. The 2-and 5-year OS rates were 35.3 and 2.4% in the ChT/TRT group, and 14.5 and 2.4% in the ChT group, respectively (P<0.05). The 1-and 2-year PFS rates were 35.4 and 6.0% in the ChT/TRT group, and 20.5 and 6.0% in the ChT group, respectively (P<0.05). The median PFS was 11 months in the 20 patients receiving TRT at 45 Gy/30 fractions twice daily, and 9 months in the 22 patients receiving TRT at 60 Gy/30 fractions daily (P=0.043). Multivariate analysis revealed that receiving ≥4 cycles of chemotherapy (P=0.001) and TRT (P=0.008) were favorable prognostic factors for OS. It was concluded that the addition of TRT improves the OS and PFS rates of patients with ES-SCLC, and TRT administration at 45 Gy/30 fractions twice daily is feasible and tolerable for the treatment of ES-SCLC. Thus, TRT and receiving ≥4 cycles of chemotherapy are independent, favorable prognostic factors for OS in patients with ES-SCLC. IntroductionLung cancer is a leading cause of cancer-associated mortality worldwide, with >1 million mortalities annually (1). Small-cell lung cancer (SCLC) accounts for 10-15% of lung cancer cases (2). It is estimated that 70% of patients with SCLC have extensive-stage SCLC (ES-SCLC) at the time of diagnosis (3).Currently, the first-line therapy for ES-SCLC remains dependent on platinum-based chemotherapy with cisplatin-etoposide (EP) (4). The addition of thoracic radiotherapy (TRT) is suggested in certain patients due to its confirmed value in the improvement of the overall survival (OS) rate (5,6). Although SCLC is sensitive to chemotherapy and radiotherapy, with a 60-80% response rate, the median survival rate of patients with ES-SCLC is estimated to be only 7-12 months following 4-6 cycles of standard chemotherapy (4).Systemic chemotherapy in combination with concurrent TRT have been demonstrated to be effective in the treatment of limited-stage SCLC (LS-SCLC) by improving the progression-free survival (PFS) and OS rates (7-9). The National Comprehensive Cancer Network (NCCN) guidelines recommend that TRT should be initiated during the first or second cycles of chemotherapy in cases of LS-SCLC at 45 Gy administered twice per day in 1.5 Gy fractions, or 60-70 Gy in 2 Gy daily fractions (10-12). However, the effect of TRT on ES-SCLC remains unknown. The present retrospective study evaluated the effect of 3-dimensional (3D) conformal ...

Outcomes and Prognostic Factors of Small Cell Lung Cancer: A Retrospective Study

“…In our patients, about 24% were presented by single site of metastasis while 11% had ≥2 sites and bone was the most common site of metastasis followed by brain similar to what reported by Luan et al [28]. However, others found that the frequency of metastatic sites were liver then brain and bone [29] [30].…”

“…As regard prognostic factors for survival; ECOG of 0 -1 was associated with significantly higher survival (P = 0.04) comparable to that recorded by Nathan R et al [35] who explained that by receiving more often full dose therapy in patients with ECOG 0 -1 than those with ECOG ≥ 2. 2-year survival rate 35% with median overall survival time of 14 months comparable to what reported by Luan Z et al [28] and Unalmis et al [29]. While Ramlov A et al [50] recorded higher median survival time which can be attributed to higher percentage of patients with LD-SCLC in their study (62.7%).…”

“…In our study, leucopenia was the most prevalent hematologic toxicity (41.3%) while esophagitis (23.8%) followed by pneumonitis (15.9%) were the most frequent non hematologic one. But Luanz reported incidence of pneumonitis and esophagitis of 1.8% and 1.2% respectively [28]. This can be explained by using 3D conformal TRT for all his patients while only 7.6% of our group treated by 3D conformal TRT.…”

Clinical Outcomes of Extensive Stage Small Cell Lung Cancer Patients Treated With Thoracic Radiotherapy at Different Timing and Fractionation

“…We analyzed those patients with CR and PR to systemic therapy but got discordant conclusion as the previous two studies mentioned above. Moreover, receiving TRT at 45Gy/30 fractions twice per day translated into a survival bene t in the OS and PFS in contrast with receiving radiotherapy at 60Gy/30 fractions daily, which was concurs with the ndings of previous studies by Luan Z et al [24]. Different radiation fractionations employed may lead to the opposite result.…”

Evaluation of the efficacy of cisplatin–etoposide and the role of thoracic radiotherapy and prophylactic cranial irradiation in LCNEC

“…This study confirmed that TRT in addition to PCI should be considered for all patients with ES-SCLC who respond to chemotherapy. Other prospective and retrospective studies reported positive results with TRT in ES-SCLC in terms of survival and RR [37–39]. …”