Effect of radiotherapy planning complexity on survival of elderly patients with unresected localized lung cancer

The Changing Paradigm of Radiotherapy in the Elderly Population

There is increasing awareness of the special needs for care of the elderly cancer patient. Newer precise conformal radiotherapy techniques allow the safe delivery of higher doses of radiotherapy to the target tumor while reducing the dose to surrounding critical organs. This has led to a shortening of radiotherapy protocols for both curative and palliative indications. We review these novel techniques and protocols and the published clinical studies that include elderly patients treated with these techniques. Despite the fact that the elderly are a growing significant proportion of cancer patients, and the need for radiotherapy in the elderly is expected to rise with increasing life expectancy, they are underrepresented in most clinical studies of radiotherapy, and there are few studies specifically investigating radiotherapy in the elderly. The treatment of early-stage primary lung cancer with stereotactic body radiotherapy is a prime example how new highly conformal techniques and shortened treatment protocols are changing the approach to radiotherapy in the elderly. With improved imaging and radiotherapy treatment precision, it is expected that such techniques will become increasingly used in other cancer sites. It is important for radiation oncologists to be aware of the special needs of the elderly cancer patient and in particular to assess these patients based on functional status and not only chronological age. In addition, geriatric oncologists should be aware of modern radiotherapy techniques that can be particularly appropriate for the elderly patient.

Causes of death in long-term lung cancer survivors: a SEER database analysis

BACKGROUND

Long-term (>5 years) lung cancer survivors represent a small but distinct subgroup of lung cancer patients and information about the causes of death of this subgroup is scarce.

METHODS

The Surveillance, Epidemiology and End Results (SEER) database (1988-2008) was utilized to determine the causes of death of long-term survivors of lung cancer. Survival analysis was conducted using Kaplan-Meier analysis and multivariate analysis was conducted using a Cox proportional hazard model. Clinicopathological characteristics and survival outcomes were assessed for the whole cohort.

RESULTS

A total of 78,701 lung cancer patients with >5 years survival were identified. This cohort included 54,488 patients surviving 5-10 years and 24,213 patients surviving >10 years. Among patients surviving 5-10 years, 21.8% were dead because of primary lung cancer, 10.2% were dead because of other cancers, 6.8% were dead because of cardiac disease and 5.3% were dead because of non-malignant pulmonary disease. Among patients surviving >10 years, 12% were dead because of primary lung cancer, 6% were dead because of other cancers, 6.9% were dead because of cardiac disease and 5.6% were dead because of non-malignant pulmonary disease. On multivariate analysis, factors associated with longer cardiac-disease-specific survival in multivariate analysis include younger age at diagnosis (p < .0001), white race (vs. African American race) (p = .005), female gender (p < .0001), right-sided disease (p = .003), adenocarcinoma (vs. large cell or small cell carcinoma), histology and receiving local treatment by surgery rather than radiotherapy (p < .0001).

CONCLUSION

The probability of death from primary lung cancer is still significant among other causes of death even 20 years after diagnosis of lung cancer. Moreover, cardiac as well as non-malignant pulmonary causes contribute a considerable proportion of deaths in long-term lung cancer survivors.

Consensus Statement on Proton Therapy in Early-Stage and Locally Advanced Non-Small Cell Lung Cancer

Radiation dose escalation has been shown to improve local control and survival in patients with non-small cell lung cancer in some studies, but randomized data have not supported this premise, possibly owing to adverse effects. Because of the physical characteristics of the Bragg peak, proton therapy (PT) delivers minimal exit dose distal to the target volume, resulting in better sparing of normal tissues in comparison to photon-based radiation therapy. This is particularly important for lung cancer given the proximity of the lung, heart, esophagus, major airways, large blood vessels, and spinal cord. However, PT is associated with more uncertainty because of the finite range of the proton beam and motion for thoracic cancers. PT is more costly than traditional photon therapy but may reduce side effects and toxicity-related hospitalization, which has its own associated cost. The cost of PT is decreasing over time because of reduced prices for the building, machine, maintenance, and overhead, as well as newer, shorter treatment programs. PT is improving rapidly as more research is performed particularly with the implementation of 4-dimensional computed tomography-based motion management and intensity modulated PT. Given these controversies, there is much debate in the oncology community about which patients with lung cancer benefit significantly from PT. The Particle Therapy Co-operative Group (PTCOG) Thoracic Subcommittee task group intends to address the issues of PT indications, advantages and limitations, cost-effectiveness, technology improvement, clinical trials, and future research directions. This consensus report can be used to guide clinical practice and indications for PT, insurance approval, and clinical or translational research directions.

Comparative effectiveness research in radiation oncology: assessing technology

Technological advances are a major contributor to rising costs in health care, including radiation oncology. Despite the large amount spent on new technologies, technology assessment remains inadequate, leading to potentially costly and unnecessary use of new technologies. Comparative effectiveness studies have an important role to play in evaluating the benefits and harms of new technologies compared with older technologies and have been identified as a priority area for research by the Radiation Oncology Institute. This article outlines the elements of effective technology assessment, identifies key challenges to comparative effectiveness studies of new radiation oncology technologies, and reviews several examples of comparative effectiveness studies in radiation oncology, including studies on conformal radiation, IMRT, proton therapy, and other concurrent new technologies.

Effectiveness of radiation therapy alone for elderly patients with unresected stage III non-small cell lung cancer

PURPOSE

Chemoradiotherapy is the standard of care for unresectable stage III non-small cell lung cancer (NSCLC). Elderly patients, who are often considered unfit for combined chemoradiotherapy, frequently receive radiation therapy (RT) alone. Using population-based data, we evaluated the effectiveness and tolerability of lone RT in unresected elderly stage III NSCLC patients.

METHODS AND MATERIALS

Using the Surveillance, Epidemiology and End Results (SEER) registry linked to Medicare records we identified 10,376 cases of unresected stage III NSCLC that were not treated with chemotherapy, diagnosed between 1992 and 2007. We used logistic regression to determine propensity scores for RT treatment using patients' pre-treatment characteristics. We then compared survival of patients who underwent lone RT vs. no treatment using a Cox regression model adjusting for propensity scores. The adjusted odds for toxicity among patients treated with and without RT were also estimated.

RESULTS

Overall, 6468 (62%) patients received lone RT. Adjusted analyses showed that RT was associated with improved overall survival in unresected stage III NCSLC (hazard ratio [HR]: 0.76; 95% confidence interval [CI]: 0.74-0.79) after controlling for propensity scores. RT treated patients had an increased adjusted risk of hospitalization for pneumonitis (odds ratio [OR]: 89, 95% CI: 12-636), and esophagitis (OR: 8, 95% CI: 3-21).

CONCLUSIONS

These data suggest that use of RT alone may improve the outcomes of elderly patients with unresected stage III NSCLC. Severe toxicity, however, was considerably higher in the RT treated group. The potential risks and benefits of RT should be carefully discussed with eligible elderly NSCLC patients.

Adjuvant treatment for elderly patients with early-stage lung cancer treated with limited resection

OBJECTIVES

Limited resection is commonly used for treating older patients with early-stage non-small cell lung cancer (NSCLC) who cannot tolerate lobectomy. However, parenchymal-sparing procedures leave patients at increased risk of recurrence. The role of postoperative radiotherapy (PORT) and chemotherapy after limited resection is not established.

METHODS

We identified 1,929 patients with stage I-II (≤ 5 cm in size) NSCLC who underwent limited resection (wedge or segmentectomy) from the Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database. Using propensity score methods, we compared toxicity and survival of patients treated with limited resection alone, PORT, adjuvant chemotherapy, or PORT and chemotherapy. We conducted secondary analysis stratifying the sample by size (>2-5 cm), stage (IA vs. IB/IIA), and type of limited resection (wedge resection vs. segmentectomy).

MEASUREMENTS AND MAIN RESULTS

Overall, 1,656 (85.8%), 159 (8.3%), 74 (3.8%), and 40 (2.1%) patients were treated with limited resection alone, PORT, adjuvant chemotherapy, or PORT and chemotherapy, respectively. Adjusted analysis using inverse probability weighting showed that PORT (hazard ratio [HR], 1.57; 95% confidence interval [CI], 1.45-1.69), adjuvant chemotherapy (HR, 1.48; 95% CI, 1.36-1.61), and PORT and chemotherapy (HR, 1.73; 95% CI, 1.61-1.86) were associated with worse survival compared with limited resection alone. Similar results were obtained in secondary analyses. Compared with limited resection alone, the adjusted odds ratios for toxicity were 1.97 (95% CI, 1.6-2.4), 3.15 (95% CI, 2.58-3.85), 2.59 (95% CI, 2.0-3.4) for PORT, chemotherapy, and PORT and chemotherapy, respectively.

CONCLUSIONS

PORT and adjuvant chemotherapy are not beneficial and appear to be associated with increased toxicity and worse survival after limited resection in elderly patients with early-stage NSCLC. Alternative strategies should be explored to improve local control.

Developments in early-stage NSCLC: advances in radiotherapy

An increase in the number of predominantly elderly patients with early-stage non-small-cell lung cancer is anticipated in many Western populations. Patients often have major co-morbidities and are at increased risk for surgical morbidity and mortality. In the past decade, the use of stereotactic ablative radiotherapy (SABR) has achieved excellent results, with only mild toxicity in such vulnerable patient groups, leading to SABR becoming accepted as a standard of care for unfit patients in several countries. The planning and delivery of SABR has rapidly improved in recent years, particularly with the use of 'on-board' imaging at treatment units, and shortened treatment delivery times. Increasingly, more central tumors are being treated using lower doses per fraction (so-called risk-adapted schemes). It is also becoming clear that long-term follow-up should take place at specialist centers in order to distinguish the evolving fibrosis that is frequently observed from the relatively infrequent local recurrences. Given the high local control rates and limited toxicity, increasing attention is being paid to the use of SABR in the subgroup of so-called borderline operable patients, and clinical trials comparing surgery and SABR in these patients are ongoing.

Postoperative radiotherapy for elderly patients with stage III lung cancer

BACKGROUND

The potential role of postoperative radiation therapy (PORT) for patients who have completely resected, stage III nonsmall cell lung cancer (NSCLC) with N2 disease remains controversial. By using population-based data, the authors of this report compared the survival of a concurrent cohort of elderly patients who had N2 disease treated with and without PORT.

METHODS

By using the Surveillance, Epidemiology, and End Results (SEER) registry linked to Medicare records, 1307 patients were identified who had stage III NSCLC with N2 lymph node involvement diagnosed between 1992 and 2005. Propensity scoring methods and instrumental variable analysis were used to compare the survival of patients who did and did not receive PORT after controlling for selection bias.

RESULTS

Overall, 710 patients (54%) received PORT. Propensity score analysis indicated that PORT was not associated with improved survival in patients with N2 disease (hazard ratio [HR], 1.11; 95% confidence interval [CI], 0.97-1.27). Analyses that were limited to patients who did or did not receive chemotherapy, who received intermediate-complexity or high-complexity radiotherapy planning, or adjusted for time trends produced similar results. The instrumental variable estimator for the absolute improvement in 1-year and 3-year survival with PORT was -0.04 (95% CI, -0.15 to 0.08) and -0.08 (95% CI, -0.24 to 0.15), respectively.

CONCLUSIONS

The current data suggested that PORT is not associated with improved survival for elderly patients with N2 disease. These findings have important clinical implications, because SEER data indicate that a large percentage of elderly patients currently receive PORT despite the lack of definitive evidence about its effectiveness. The potential effectiveness of PORT should be evaluated further in randomized controlled trials.

Radiotherapy and chemotherapy for elderly patients with stage I-II unresected lung cancer

Radiotherapy (RT) is the standard therapy for unresected stage I-II nonsmall cell lung cancer (NSCLC). Using population-based data, we compared survival and toxicity among unresected elderly patients treated with combined chemoradiotherapy (CRT) or RT alone. Using the Surveillance, Epidemiology and End Results (SEER) registry (National Cancer Institute, Bethesda, MD, USA) we identified 3,006 cases of unresected stage I-II NSCLC. We used propensity score methods to compare survival and rates of toxicity of patients treated with RT versus CRT. Overall, 844 (28%) patients received CRT. Adjusted analyses showed that CRT was associated with improved survival (hazard ratio 0.85, 95% CI 0.78-0.94). Combination therapy was also associated with better survival among stage I patients treated with intermediate complexity RT (HR 0.80, 95% CI 0.70-0.90); however, no difference in survival was observed among patients treated with complex RT. In stage II patients, CRT was associated with improved survival regardless of the RT technique (HR 0.61-0.72). CRT was associated with increased odds of toxicity. Despite increased toxicity, CRT may improve survival of elderly unresected patients with stage II disease as well as stage I NSCLC treated with intermediate RT complexity. Randomised trials are needed to clarify the balance of benefits and risk of CRT in unresected patients.