Balancing the possible effectiveness of postoperative radiotherapy for non-small-cell lung cancer against the possible detriment of radiation-induced toxicity

Lung dose and the potential risk of death in postoperative radiation therapy for non-small cell lung cancer: A study using the method of stratified grouping

PURPOSE

Postoperative radiation therapy may have a detrimental effect on survival in patients with non-small cell lung cancer. We investigated the association of the lung radiation dose with the risk of death in patients treated with postoperative radiation therapy.

METHODS

We analyzed 178 patients with non-small cell lung cancer who received postoperative radiation therapy. The mean lung dose was calculated from dose-volume data, and we categorized patients into the high and low lung dose groups using 2 different methods; (1) simple grouping using the median lung dose of all patients, and (2) stratified grouping using the median lung dose of each subgroup sharing the same confounders. We compared clinical variables, and survival between the high and low lung dose groups.

RESULTS

In the simple grouping, there were no significant differences in survivals between the high and low lung dose groups. After stratification, the overall survival of low lung dose group was significantly longer than that of high lung dose group (5-year survival, 60.1% vs. 35.3%, p = 0.039). On multivariable analyses, the lung dose remained a significant prognostic factor for overall survival (hazard ratio, HR = 2.08, p = 0.019).

CONCLUSIONS

The lung dose was associated with the risk of death in patients with non-small cell lung cancer having the same confounders. Further studies evaluating the risk of death according to the lung dose will be helpful to administer more precise and individualized postoperative radiation therapy.

The effects of radiotherapy on the survival of patients with unresectable non-small cell lung cancer

INTRODUCTION

Lung cancer represents the leading cause of cancer mortality across the worlds. At present, less than 30% of the patients can undergo curative surgery, while the majority of them (65%) are diagnosed with metastatic disease and directed to systemic treatments. In this context there is a subset of patients (25%) with locally advanced stage disease whose outcome might be improved by using combined strategies of treatment including chemotherapy, radiotherapy and surgery. Areas covered: Here we reviewed possible combination strategies aimed to improve the outcome of lung cancer patients, focusing on the role of radiotherapy both in the adjuvant and oligo-metastatic setting and in synergy with immunotherapy, and finally, we afforded the new challenges concerning the advanced RT and precision oncology. We carried out a focused analysis concerning the key clinical management weaknesses as well as the potential that current research holds. Expert commentary: We believe that the most promising clinical trials in this specific patient subset will build their rationale on the results of well-designed translational models aimed to test the combination of cytotoxic drugs, radiobiology, and immune-pharmacology. In this context, remarkable investigational fields are focused on the attempt to combine radiotherapy with chemo-immunological strategies and precision medicine protocols.

Delineation of clinical target volume for postoperative radiotherapy in stage IIIA-pN2 non-small-cell lung cancer

With the high locoregional relapse rate and the improvement of radiation technology, postoperative radiotherapy (PORT) has been widely used in the treatment of completely resected stage IIIA-pN2 non-small-cell lung cancer (NSCLC). However, there is still no definitive consensus on clinical target volume for the pN2 subgroup. This review will discuss how to delineate the clinical target volume (CTV) for pN2 subgroups of IIIA-N2 NSCLC based on the published literature and to investigate the optimal PORT CTV in this cohort of patients. Besides overall survival (OS), locoregional recurrence (LR), and radiotherapy-related toxicity of this subset of the population in the modern PORT era, selection of proper patients will also be considered in this review. In summary, it is appropriate to include involved lymph node stations and uninvolved stations at high risk in PORT CTV for patients with pN2 disease when PORT is administered. PORT can reduce LR and has the potential to improve OS. In the current era of modern radiation technology, PORT can be administered safely with well-tolerated toxicity. Clinicopathological characteristics may be helpful in selecting proper candidates for PORT.

Trends in the use of postoperative radiotherapy for resected non–small-cell lung cancer

PURPOSE

A 1998 meta-analysis of postoperative radiotherapy (PORT) for non-small-cell lung cancer (NSCLC) found that PORT did not improve outcomes. Yet practice guidelines differ in their recommendations with regard to PORT use. We examine temporal trends in PORT use before and after the 1998 meta-analysis.

METHODS AND MATERIALS

Using data from the Surveillance, Epidemiology, and End Results (SEER) Program, we identified 22,953 patients with Stage I, II, or IIIA NSCLC who had resection between 1992 and 2002 in the United States and characterized each patient according to nodal status (N0, N1, or N2 disease). We measured use of PORT by calendar year. We examined the association between clinical and demographic characteristics and receipt of PORT using logistic regression.

RESULTS

For N0, N1, and N2 NSCLC, PORT use has declined. The proportion of patients with N0 disease receiving PORT declined from 8% in 1992 to 4% in 2002. For patients with N1 disease, PORT use declined from 51% in 1992 to 19% in 2002; and for patients with N2 disease, PORT use declined from 65% in 1992 to 37% in 2002.

CONCLUSION

In the context of uncertainty about what constitutes optimal adjuvant treatment for resected NSCLC, PORT use has substantially declined.

Long-term survivorship in lung cancer: a review

While outcome research in lung cancer has focused mainly on short-term survival and quality of life (QoL), information on long-term (ie, > 5 years postdiagnosis) lung cancer survivorship remains limited. This review addresses the epidemiologic significance of long-term lung cancer (LTLC) survivors, summarizes the current knowledge on their health and QoL, and suggests areas for further research in LTLC survivorship. Based on a small body of literature, lung cancer survivors do not experience the same quantity and QoL as their age-matched peers or as survivors of other cancers. Survival among 5-year survivors of lung cancer relative to the general US population with the same demographic characteristics is approximately 60%, and lung cancer survivors score lowest in health utility among long-term survivors of other cancers. Approximately one-quarter of long-term lung cancer (LTLC) survivors were significantly restricted in physical ability or reported significant depressive symptoms. There is a need to identify and intervene with subgroups of survivors who are at an elevated risk of premature death and diminished QoL. Lung cancer-specific survival alone does not reflect the overall illness burden in LTLC survivors. Patient care in lung cancer survivors should be continuous and comprehensive in considering multiple causes of health deterioration. Multidisciplinary research in epidemiologic, clinical, and basic science approaches is warranted to further our knowledge base for optimal long-term management and to develop the necessary intervention strategies among LTLC survivors.

Post-operative radiotherapy (PORT) or chemoradiotherapy (CPORT) following resection of stages II and IIIA non-small cell lung cancer (NSCLC) does not increase the expected risk of death from intercurrent disease (DID) in Eastern Cooperative Oncology Group (ECOG) trial E3590

To determine the influence of adjuvant therapy on the risk of DID following resection of NSCLC, we compared the actuarial rate of non-cancer related deaths of patients who had been entered in Eastern Cooperative Oncology Group E3590 (a phase III trial of adjuvant therapy in patients with completely resected stages II and IIIA NSCLC) to the actuarial death rate of age and gender matched controls. Following surgery, patients were randomized to receive either PORT (5040 cGy in 28 daily fractions) or CPORT (PORT plus four cycles of cisplatin (60 mg/m2, day 1) and etoposide (120 mg/m2, days 1-3) administered concurrently). The study accrued 488 patients, 242 to the PORT only arm and 246 to the CPORT arm. The overall 4 years actuarial rate of DID for the two arms combined, with a median follow-up of 82 months, was 12.9%, not significantly different from the 10.1% expected rate of DID, based on mortality rates for age and gender matched controls derived from US vital statistics and corrected for smoking status (p=0.16). Survival distributions with regard to DID did not differ between the two treatment arms (p=0.96). DID increased with age (treated as a continuous variable, p<0.01), but was not affected by histology, side of chest irradiated, type of surgery, FEV1 or weight loss in the previous 6 months. The risk of DID following resection of stages II and IIIA NSCLC is not increased in patients who received PORT or CPORT.

Results of clinical trials of multimodality therapy for resectable nonsmall-cell lung cancer

More than 50% of patients presenting with so-called early stage or surgical disease nonsmall-cell lung cancer will die of their cancer despite resection. Over the years, postoperative efforts to improve the survival of these patients have been disappointing. There is presently a lot of enthusiasm surrounding the strategy of preoperative or induction chemotherapy in the treatment of such patients. Worldwide, at least 4 large-scale ongoing cooperative group trials are evaluating this question at the present time. Only by completing these trials in a timely manner will we know if induction chemotherapy should become the standard of care for all patients with surgical disease nonsmall-cell lung cancer.