Late-course High-dose Radiotherapy Combined With Concurrent Chemotherapy For Locally Advanced Non-small Cell Lung Cancer

Objective To evaluate the effect and patient’s tolerance of late-course high-dose radiotherapy (LCHDRT) combined with concurrent chemotherapy for locally advanced non-small cell lung cancer (NSCLC). Methods from May 2000 to May 2006,73 such patients were entered into this study. The patients characteristic were:54 male and 19 female, with median age of 65 years (range 40 to 75); Karnofsky performance score ≥70; Stage Ⅲ A 18 and ⅢB 55, Squamous cell carcinoma 51 and adenocarcinoma 22. The treatment regime consisted of conventional radiotherapy first (40Gy/20 f/4 w), followed by LCHDRT (24-30Gy/6f/2w, tumor α/β=10Gy, BED=81.6-93Gy) combined with concurrent chemotherapy. Conventional irradiation field encompassed the primary lesion, hilum of lung and mediastinal lymph drainage region. LCHDRT focused on the primary lesion only, with ≥95% isodose curve covering the planning target volume (PTV) and the target dose was prescribed to PTV. Supraclavicular metastases lymph node was treated by 6 MV x-ray and electron beam to a total dose of 65-70Gy. Chemotherapy regime consisted of vinorelbine (25mg/m 2 d1、8i v) and cisplatin (30mg/d, d1-3, iv gtt) in the 1st and 5th weeks. Results leukopenia and radiation-induced pneumonitis, as shown by the WHO staging system were the most common acute toxicities. In V20≤25%, of the 29 cases 5 (17.2%) happened radiation-induced pneumonitis only. But in 25%<V20≤30%, of the 44 cases 29 (65.9%) happened radiation-induced pneumonitis (X2=16.63, P< 0.01). It showed that patients accompany increment of V20, the happening rate of radiation-induced pneumonits probability will be increased. The other acute toxicities such as nausea, fever, radiation-induced esophagitis, hemoglobin decrease and throm bocytopenia were mainly grade 1 or 2. After symptomatic treatment, all patients completed the planned treatment without interruption except 4 patients above 70 old years of grade 3 radiation-induced pneumonitis. Late lung radio-fibrosis was 34.3% (25/73). Before the end of the second month after treatment, the complete response (CR) and partial response (PR) rates were 17.8%(13/73)and 69.9%(51/73), respectively, with CR+PR rate of 87.7%(64/73). The 1-,3-,5-year local control and overall survival rates as monitored by the x2 test method were 82.2%,60.3%, 50.7% and 57.5%,23.3%,13.7%, respectively. Conclusions LCHDRT combined with concurrent chemotherapy shows a promising results, but the rational time-dose-fraction model still need further observation. PET-CT and tagerting drugs perhaps can lead a bright future on radiotherapy combined with concurrent chemotherapy for locally advanced NSCLC.