Patterns of Radiation Therapy Practice in Nonmetastatic Non—Small-Cell Lung Cancer: Results of Web-Based Patterns of Care Study in Korea

Abstract Background A Patterns-of-Care Study (PCS) was conducted to determine the patterns of evaluation and treatment for nonmetastatic non— small-cell lung cancer (NSCLC) in Korea. Patients and Methods A Web-based data system for Korean PCS was developed, and a national survey was conducted. Patients who received thoracic radiation therapy (RT) for clinical or pathologic stage I-III NSCLC without other malignancy in 1998 and 1999 were eligible and randomly selected by power allocation method. Results The records of 446 selected patients from 19 institutions were reviewed, and 10 patients were excluded because of incomplete clinical information. Accordingly, 436 patients were the subjects of this study, with a median age of 62.2 years (range, 33.1–88 years) and male-to-female ratio of 86:14. The histologies were squamous cell carcinoma in 61.2%, adenocarcinoma in 28.4%, large-cell carcinoma in 2.3%, and NSCLC not otherwise specified in 8% of patients, respectively. Bone scan, abdominal ultrasonography or computed tomography (CT), brain CT or magnetic resonsance imaging, and positron emission tomography were examined in 92.5%, 81.5%, 44.8%, and 26.6% of patients, respectively. The clinical stage was I in 8.9%, II in 12.2%, IIIA in 37.4%, and IIIB in 41.5%, respectively. Regarding treatment modalities, RT was used alone in 38.1%; RT combined with operation in 22.9%; RT combined with chemotherapy in 27.1%; and trimodalities including RT, operation, and chemotherapy in 11.9%. The median total dose was 59.4 Gy with daily median fraction size of 1.8 Gy, and the percent delivered dose > 90% was achieved in 87.6%. Most of patients received RT in supine position (99.3%) with beam direction of anterior-posterior/posterior-anterior (95.6%) as their first RT plan and with photon energy of 6 MV (42%) followed by 10 MV (41.7%). The chemotherapy-based planning was used in 2.3 % and 32.6% for their first and second RT plan, respectively. The 3-or-more RT planning was performed in 13.5% of patients. Elective nodal irradiation was used in 87.8% of patients, and the N2 nodal station (48.6%) was most frequently included. The 8% of patients received thoracic RT based on prospective protocol. Conclusion This study is the first PCS for NSCLC conducted in Korea. We confirmed that various types of RT planning were used according to each institution, but beam delivery techniques were not much different between 1998 and 1999. Another PCS is planned to evaluate changing trends in national practice.