Role of Postoperative Radiotherapy in Resected Non-Small Cell Lung Cancer: A Reassessment Based on New Data

Abstract

After completing this course, the reader will be able to: 1. Identify patients with non-small cell lung cancer who may benefit from postoperative radiotherapy based upon current evidence. 2. Summarize the results of analyses of both older and more recent data regarding postoperative radiotherapy in NSCLC patients. ABSTRACT In completely resected non-small cell lung cancer (NSCLC) patients with pathologically involved mediasti-nal lymph nodes (N2), administration of adjuvant platinum based chemotherapy is now considered the standard of care, based on level 1 evidence. The role of postoperative radiation therapy (PORT) in this group of patients remains controversial. The PORT meta-analysis published in 1998 concluded that adjuvant radiotherapy was detrimental to patients with early-stage completely resected NSCLC, but that the role of PORT in the treatment of tumors with N2 involvement was unclear, and that further research was warranted. Recent retrospective and non-randomized studies, as well as subgroup analyses of recent randomized trials evaluating adjuvant chemotherapy, provide evidence of the possible benefit of PORT in patients with mediastinal nodal involvement. The role of PORT is also a valid question in patients with proven N2 disease who have undergone only induction chemotherapy followed by surgery, because the local recurrence rate for such patients varies in the range of 20%-60%. Based on the currently available data, PORT should be discussed for fit patients with completely resected NSCLC with N2 nodal involvement, preferably after completion of adju-vant chemotherapy. There is a need for new randomized evidence to evaluate PORT using the modern three-dimensional conformal radiation technique, with attention paid to reducing the risk for, particularly, pulmonary and cardiac toxicity. A new large multi-institutional randomized trial evaluating PORT in this patient population is needed and now under way. The Oncologist 2011;16:672-681

Association between clinicopathological factors and postoperative radiotherapy in patients with completely resected pathological N2 non-small cell lung cancer

“…Postoperative chemotherapy (POCT) has been demonstrated by a number of studies to improve the OS rate of patients with pN2 NSCLC and has been regarded as the gold standard of treatment (11,12). However, the risk of locoregional recurrence (LRR) remains as high as 20-40%, which associates independently with worse OS (13). Postoperative radiotherapy (PORT) holds great appeal as a means by which to reduce LRR and improve OS.…”

Simultaneously modulated accelerated radiation therapy reduces severe oesophageal toxicity in concomitant chemoradiotherapy of locally advanced non-small-cell lung cancer

“…In fact, doses around 54 Gy are considered the standard of care in the adjuvant treatment of lung cancer and other anatomic localizations. 8 There is a general agreement about target volumes that should be treated in LANSCLC, and homogeneous doses to the macroscopic and microscopic disease of 66 Gy are the standard recommendations. 7 However, doses delivered are usually limited to 60 Gy because of constraints to the OARs.…”

Perspectives on the effect of nodal downstaging and its implication of the role of surgery in stage IIIA (N2) non-small cell lung cancer

“…These data from more than 2,000 patients were individually analyzed by the PORT Meta-analysis Trialists Group (29). Doses range from 30-60 Gy historically; presently PORT is dosed in the range of 50.4-54 Gy (30). Although the methods of delivery of radiation therapy were very different than now, PORT was shown to have a detrimental effect on overall survival in stage I-II.…”