Evaluation and treatment of high-risk patients with early-stage lung cancer

The Latest on Lung Ablation

Lung cancer is the second most common cancer in both men and women. Despite smoking cessation efforts and advances in lung cancer detection and treatment, long-term survival remains low. For early-stage primary lung carcinoma, surgical resection offers the best chance of long-term survival; however, only about one-third of patients are surgical candidates. For nonsurgical candidates, minimally invasive percutaneous thermal ablation therapies have become recognized as safe and effective treatment alternatives, including radiofrequency ablation, microwave ablation, and cryoablation. Lung ablation is also an acceptable treatment for limited oligometastatic and oligorecurrent diseases. This article discusses the technologies and techniques available for tumor ablation of thoracic malignancies, as well as new treatments on the horizon.

Local Control After Stereotactic Body Radiation Therapy for Stage I Non-Small Cell Lung Cancer

PURPOSE

Numerous dose and fractionation schedules have been used to treat medically inoperable stage I non-small cell lung cancer (NSCLC) with stereotactic body radiation therapy (SBRT) or stereotactic ablative radiation therapy. We evaluated published experiences with SBRT to determine local control (LC) rates as a function of SBRT dose.

METHODS AND MATERIALS

One hundred sixty published articles reporting LC rates after SBRT for stage I NSCLC were identified. Quality of the series was assessed by evaluating the number of patients in the study, homogeneity of the dose regimen, length of follow-up time, and reporting of LC. Clinical data including 1, 2, 3, and 5-year tumor control probabilities for stages T1, T2, and combined T1 and T2 as a function of the biological effective dose were fitted to the linear quadratic, universal survival curve, and regrowth models.

RESULTS

Forty-six studies met inclusion criteria. As measured by the goodness of fit χ2/ndf, with ndf as the number of degrees of freedom, none of the models were ideal fits for the data. Of the 3 models, the regrowth model provides the best fit to the clinical data. For the regrowth model, the fitting yielded an α-to-β ratio of approximately 25 Gy for T1 tumors, 19 Gy for T2 tumors, and 21 Gy for T1 and T2 combined. To achieve the maximal LC rate, the predicted physical dose schemes when prescribed at the periphery of the planning target volume are 43 ± 1 Gy in 3 fractions, 47 ± 1 Gy in 4 fractions, and 50 ± 1 Gy in 5 fractions for combined T1 and T2 tumors.

CONCLUSIONS

Early-stage NSCLC is radioresponsive when treated with SBRT or stereotactic ablative radiation therapy. A steep dose-response relationship exists with high rates of durable LC when physical doses of 43-50 Gy are delivered in 3 to 5 fractions.

Early death in Danish stage I lung cancer patients: a population-based case study

OBJECTIVE

Clinical stage (c-stage) at diagnosis is the most significant prognostic marker for patients with cancer, where 1- and 5-year survival rates as main landmarks when assessing outcomes. This is a population-based case study of Danish c-stage I lung cancer patients who were considered candidates for curative therapy and then died within 1 year after diagnosis (cases). Cases were identified in the Danish Lung Cancer Register (DLCR), and medical records were used to retrieve treatment details and cause of death (CoD). Our aims were, if possible, to identify and describe clusters of patients, in terms of CoD and treatment modality at risk for an adverse short-term outcome.

RESULTS

Patients who died early were more frequently male, older, had squamous-cell histology, were less frequently surgically treated and generally had a higher burden of comorbidity. In terms of CoD, 29% died of lung cancer with distant recurrence (DR) as the most common type of recurrence (55%). Death from co-morbidity occurred for 23%, where the largest proportion (36%) died from another cancer. Nineteen percentage died from treatment complications, with the majority being male (p < .001). The remainder died of unknown or other causes.

CONCLUSIONS

Lung cancer with DR remains the most common CoD. Identifying and accordingly treating patients at risk for DR could potentially improve outcomes. Further studies of the predominantly male subgroup of patients who die of treatment complications are needed. Death from co-morbidity especially in patients with another cancer is a significant CoD and when assessing the quality of lung cancer care a competing event.

Use of frailty to predict survival in elderly patients with early stage non-small-cell lung cancer treated with stereotactic body radiation therapy

OBJECTIVES

Frailty has been shown to increase morbidity and mortality independent of age, but studies are lacking in radiation oncology. This study evaluates a modified frailty index (mFI) in predicting overall survival (OS) and non-cancer death for Stage I/II [N0M0] Non-Small-Cell Lung Cancer (NSCLC) patients treated with Stereotactic Body Radiation Therapy (SBRT).

MATERIALS AND METHODS

Medical records for all patients with Stage I/II NSCLC treated at our institution with SBRT from 2009 to 2014 were reviewed. A validated mFI score, consisting of 11 variables was calculated, classifying patients as non-frail (0-1) or frail (≥2). Primary endpoint (OS) was analyzed using Kaplan-Meier method and log-rank. Secondary endpoint, non-cancer death, was analyzed using Fine-Gray's method, with death from lung cancer as a competing risk.

RESULTS

Patient cohort consisted of 38 (27.3%) non-frail and 101 (72.7%) frail [median total mFI score 3.0 (range 0-7)]. Median age and pack-year history was 74 and 46years, respectively. Median follow-up among survivors was 38.5months (range 4.0-74.1months). Frailty was associated with a lower 3-year OS (37.3% vs. 74.7%; p=0.003) and 3-year cumulative incidence of non-cancer death (36.7% vs. 12.5%; p=0.02). Frailty remained significant in the multivariate model [OS HR for mFI ≥2: 2.25 (1.14-4.44); p=0.02].

CONCLUSION

Frailty is associated with lower OS in older patients with early stage NSCLC treated with SBRT, yet frail patients survived a median 2.5years, and were more likely to die of causes unrelated to the primary lung cancer, suggesting SBRT should be considered even in older patients deemed unfit for surgery.

Comparison of the Effectiveness of Radiofrequency Ablation With Stereotactic Body Radiation Therapy in Inoperable Stage I Non-Small Cell Lung Cancer: A Systemic Review and Pooled Analysis

PURPOSE

To performed a systematic review and pooled analysis to compare clinical outcomes of stereotactic body radiation therapy (SBRT) and radiofrequency ablation (RFA) for the treatment of medically inoperable stage I non-small cell lung cancer.

METHODS AND MATERIALS

A comprehensive literature search for published trials from 2001 to 2012 was undertaken. Pooled analyses were performed to obtain overall survival (OS) and local tumor control rates (LCRs) and adverse events. Regression analysis was conducted considering each study's proportions of stage IA and age.

RESULTS

Thirty-one studies on SBRT (2767 patients) and 13 studies on RFA (328 patients) were eligible. The LCR (95% confidence interval) at 1, 2, 3, and 5 years for RFA was 77% (70%-85%), 48% (37%-58%), 55% (47%-62%), and 42% (30%-54%) respectively, which was significantly lower than that for SBRT: 97% (96%-98%), 92% (91%-94%), 88% (86%-90%), and 86% (85%-88%) (P<.001). These differences remained significant after correcting for stage IA and age (P<.001 at 1 year, 2 years, and 3 years; P=.04 at 5 years). The effect of RFA was not different from that of SBRT on OS (P>.05). The most frequent complication of RFA was pneumothorax, occurring in 31% of patients, whereas that for SBRT (grade ≥3) was radiation pneumonitis, occurring in 2% of patients.

CONCLUSIONS

Compared with RFA, SBRT seems to have a higher LCR but similar OS. More studies with larger sample sizes are warranted to validate such findings.

Lung cancer in elderly patients

There is a worldwide-accepted evidence of a population shift toward older ages. This shift favors an increased risk of developing lung cancer that is primarily a disease of older populations. Decision making is extremely difficult in elderly patients, since this group is under-represented in clinical trials with only 25% of them historically opening to patients older than 65 years. For all these reasons, a "customized" preoperative assessment to identify physiological or pathological frailty should be encouraged since standard tools may be less reliable. The work already done to improve patient selection for lung surgery in the elderly population clearly shows that surgical resection seems the treatment of choice for early stage lung cancer. Further studies are required to improve outcome by reducing postoperative morbidity and mortality.

Use of new treatment modalities for non-small cell lung cancer care in the Medicare population

BACKGROUND

Many older patients with early stage non-small cell lung cancer (NSCLC) do not receive curative therapy. New surgical techniques and radiation therapy modalities, such as video-assisted thoracoscopic surgery (VATS), potentially allow more patients to receive treatment. The adoption of these techniques and their impact on access to cancer care among Medicare beneficiaries with stage I NSCLC are unknown.

METHODS

We used the Surveillance, Epidemiology and End Results-Medicare database to identify patients with stage I NSCLC diagnosed between 1998 and 2007. We assessed temporal trends and created hierarchical generalized linear models of the relationship between patient, clinical, and regional factors and type of treatment.

RESULTS

The sample comprised 13,458 patients with a mean age of 75.7 years. The proportion of patients not receiving any local treatment increased from 14.6% in 1998 to 18.3% in 2007. The overall use of surgical resection declined from 75.2% to 67.3% ( P , .001), although the proportion of patients undergoing VATS increased from 11.3% to 32.0%. Similarly, although the use of new radiation modalities increased from 0% to 5.2%, the overall use of radiation remained stable. The oldest patients were less likely to receive surgical vs no treatment (OR, 0.12; 95% CI, 0.09-0.16) and more likely to receive radiation vs surgery (OR, 13.61; 95% CI, 9.75-19.0).

CONCLUSION

From 1998 to 2007, the overall proportion of older patients with stage I NSCLC receiving curative local therapy decreased, despite the dissemination of newer, less-invasive forms of surgery and radiation.

Stereotactic body radiotherapy in patients with stage I non-small-cell lung cancer aged 75 years and older: retrospective results from a multicenter consortium

BACKGROUND

This study was a retrospective analysis of elderly patients treated with stereotactic body radiotherapy (SBRT) in the setting of a multi-institutional consortium.

PATIENTS AND METHODS

Three institutions pooled data on patients aged ≥ 75 years who received SBRT for stage I non-small-cell lung cancer (NSCLC). Forty-seven tumors in 46 patients were analyzed in patients aged 75 to 92 years (median, 82 years). Treatment was delivered during 2007 to 2009, with a median follow-up of 12.4 months. All patients underwent staging positron emission tomography-computed tomography (PET-CT), and 87% of tumors were confirmed by biopsy results. Total doses were 35 to 60 Gy, mainly in 3 to 5 fractions. All tumors were treated using a linear accelerator, with 96% of patients receiving 3-dimensional (3D) conformal RT and 4% undergoing intensity modulated RT (IMRT).

RESULTS

At the time of analysis, the local failure rate was 2% (1 of 47). The regional failure rate was 9% (4 of 47). The distant failure rate was 6% (3 of 47). The combined failure rate was 15% (7 of 47) because 1 patient experienced both regional and distant failure. Among 20 tumors with any acute toxicity, there were no ≥ grade 3 toxicities. Pneumonitis (n = 10) grades 1 (n = 3) and 2 (n = 2) was seen in 15% and 10% of patients, respectively; these data were missing for 25% of patients.

CONCLUSION

SBRT in patients aged ≥ 75 years with stage I NSCLC proved tolerable, with toxicity rates comparable to those in younger patients. Excellent rates of local, regional, and distant control were achieved at a median follow-up of 12.4 months. This patient population represents a rapidly growing segment of the early lung cancer population, and SBRT appears to be a safe and effective treatment option for patients who are not optimal candidates for surgery.