Radiation therapy alone in early stage non-small cell lung cancer

Wedge Resection vs. Stereotactic Body Radiation Therapy for Clinical Stage I Non-small Cell Lung Cancer: A Systematic Review and Meta-Analysis

Background

Whether wedge resection or stereotactic body radiation therapy (SBRT) has better effectiveness in treatment of clinical stage I non-small cell lung cancer (NSCLC) patients remains unclear. Here we conducted the first meta-analysis to directly compare the survival outcomes of clinical stage I NSCLCs treated with wedge resection and SBRT.

Methods

We systematically searched studies from PubMed, Embase, and Corchrane Library up to October 1, 2021. Data for analysis mainly included overall survival (OS) and disease-free survival (DFS), which were obtained directly from the text results or calculated from the Kaplan–Meier survival curve. We used the standard random-effect model test (DerSimonian and Laird method) to analyze the pooled hazard ratios (HRs) and 95% confidence intervals (CIs). The Q-test and I2-test were used to assess heterogeneity. The stability of pooled HRs was examined by sensitivity analysis.

Results

Six retrospective studies with a total of 11,813 clinical stage I NSCLCs who received wedge resection or SBRT were included. The results showed that patients receiving wedge resection had a significantly better OS (HR = 1.20, 95% CI = [1.07, 1.34], P = 0.002) than those with SBRT, but no significant difference of DFS (HR 1.53, 95% CI = [0.83–2.83], P = 0.17) was observed. There was no significant heterogeneity during our analysis, but there may be potential publication bias among these studies.

Conclusions

Our meta-analysis showed that clinical stage I NSCLCs treated with wedge resection had superior OS than those treated with SBRT. However, more prospective clinical trials should be well-designed to evaluate the optimal treatment modality of early-stage NSCLCs.

Early stage lung cancer survival after wedge resection and stereotactic body radiation

BACKGROUND

The comparative effectiveness of stereotactic body radiation therapy (SBRT) and wedge resection in the treatment of early stage lung cancer is still under debate. This meta-analysis compares the 5-year overall survival (OS) of wedge resection and SBRT in patients with stage I non-small cell lung cancer (NSCLC).

METHODS

Original research articles published between 1995 and 2017 were identified through the National Library of Medicine and National Institutes of Health PubMed database and through the reference lists of reviewed articles. Data were processed and analyzed in R (version 3.4.2) and a summary estimate that accounted for the sample size of each study was calculated. The combined percent survival was calculated using random effect models. Funnel plots were used to assess publication bias. Heterogeneity was tested using the Q statistic and the I2 statistic.

RESULTS

There were 16 studies totaling 1,984 patients with stage I NSCLC treated with wedge resection. The meta-estimate was 74% (95% CI, 66-81%), with significant heterogeneity across studies (Q =172.46, P<0.0001; I2=91.30%). Thirty-six studies including 3,309 patients with stage I NSCLC treated with SBRT/SABR produced a meta-estimate of 44% (95% CI, 38-50%), with significant heterogeneity (Q =423.55, P<0.0001; I2=91.74%). Two articles directly comparing stage I NSCLC patients treated with wedge resection to patients treated with SBRT both reported higher 5-year OS after wedge resection.

CONCLUSIONS

SBRT is a treatment option reserved to medically inoperable patients, but could be an alternative to surgery in medically operable patients who prefer a less invasive treatment. More standardized methods for data collection and reporting are necessary to allow better comparisons across published studies.

Inoperable early-stage primary and early recurrent non-small cell lung cancer: outcomes of a mono-institutional experience using a moderate hypofractionated schedule

BACKGROUND

Patients with medically inoperable early-stage non-small cell lung cancer (NSCLC) may beneficiate of a hypofractionated radiation therapy in order to intensificate the treatment and to reduce the number of hospital access.

METHODS

From 2007 to 2015, 27 patients with early-stage primary or limited loco-regional recurrent (T2a > 4 cm, T2b N0 or T1-2 N1M0) NSCLC were treated. All patients were medically inoperable or refused surgery and were treated with 60 Gy in 20 fractions, 5 times per week. Thirteen (48.1%) presented limited recurrence after surgery and 14 (51.9%) primary disease.

RESULTS

Median follow-up was 34 months. Twelve patients achieved a CR (44.4%) and 8 a PR (29.6%) with a tumour response rate of 74%. Median overall survival (OS) and 2-year OS were 34 months and 63.0%, respectively. Median and 2-year loco-regional progression-free survival (LR-PFS) were 31 months and 51.4%, respectively. Survival outcomes were statistically favourable in patients with partial or complete response with respect to patients with stable or progressive disease, whereas stage (N0 vs N1) and primary or relapse/recurrent disease not. No cases of acute toxicity > grade 2 were observed. Seven patients (25.9%) presented grade 2 late toxicities.

CONCLUSION

Sixty Gy in 20 fractions is well tolerated and achieves good clinical outcomes in early primary or recurrent NSCLC patients. A greater number of patients and a longer follow-up are necessary to confirm the results obtained with our treatment.

Advances in radiotherapy techniques and delivery for non-small cell lung cancer: benefits of intensity-modulated radiation therapy, proton therapy, and stereotactic body radiation therapy

The 21st century has seen several paradigm shifts in the treatment of non-small cell lung cancer (NSCLC) in early-stage inoperable disease, definitive locally advanced disease, and the postoperative setting. A key driver in improvement of local disease control has been the significant evolution of radiation therapy techniques in the last three decades, allowing for delivery of definitive radiation doses while limiting exposure of normal tissues. For patients with locally-advanced NSCLC, the advent of volumetric imaging techniques has allowed a shift from 2-dimensional approaches to 3-dimensional conformal radiation therapy (3DCRT). The next generation of 3DCRT, intensity-modulated radiation therapy and volumetric-modulated arc therapy (VMAT), have enabled even more conformal radiation delivery. Clinical evidence has shown that this can improve the quality of life for patients undergoing definitive management of lung cancer. In the early-stage setting, conventional fractionation led to poor outcomes. Evaluation of altered dose fractionation with the previously noted technology advances led to advent of stereotactic body radiation therapy (SBRT). This technique has dramatically improved local control and expanded treatment options for inoperable, early-stage patients. The recent development of proton therapy has opened new avenues for improving conformity and the therapeutic ratio. Evolution of newer proton therapy techniques, such as pencil-beam scanning (PBS), could improve tolerability and possibly allow reexamination of dose escalation. These new progresses, along with significant advances in systemic therapies, have improved survival for lung cancer patients across the spectrum of non-metastatic disease. They have also brought to light new challenges and avenues for further research and improvement.

Recurrent non-small cell lung cancer: evaluation of CT-guided radiofrequency ablation as salvage therapy

BACKGROUND

Radiofrequency ablation (RFA) is a potential application as a salvage tool after failure of surgery, chemotherapy, or radiotherapy of non-small cell lung cancer (NSCLC). Although several studies have evaluated the use of RFA in primary NSCLC, there is little literature on its potential application as a salvage tool.

PURPOSE

To evaluate CT-guided RFA employed as a salvage therapy for pulmonary recurrences of NSCLC after prior treatment with chemotherapy, radiation therapy, and/or surgery.

MATERIAL AND METHODS

A retrospective computer database search yielded 33 patients with biopsy proven primary NSCLC who underwent CT-guided RFA of 39 recurrent tumors following surgery, chemotherapy, and/or radiotherapy. Follow-up imaging was performed with CT and PET-CT. The endpoints of interest were progression-free survival (PFS) and time to local progression (TTLP). PFS and TTLP were compared by lesion size (<3 cm, ≥3 cm).

RESULTS

The median PFS was 8 months. For patients with a tumor size <3 cm median PFS was 11 months, whereas the median PFS of patients with a tumor size ≥3 cm was 5 months. The difference did not reach statistical significance (P = 0.09). The median TTLP of all tumors was 14 months. TTLP of ablated tumors <3 cm in size was 24 months, compared to 8 months for ablated tumors ≥3 cm in size. The difference did not reach statistical significance (P = 0.07).

CONCLUSION

RFA of recurrent NSCLC may be a valuable salvage tool to achieve local tumor control, especially in tumors measuring <3 cm in size.

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.

Inoperable early stage non-small cell lung cancer: comorbidity, patterns of care and survival

PURPOSE

To evaluate comorbidities, patterns of care and outcomes for patients with inoperable stage I and II non-small cell lung cancer (NSCLC).

MATERIALS AND METHODS

Patients diagnosed with stage I or II NSCLC in British Columbia between 1996 and 2005 who did not undergo primary surgery and were referred for oncology assessment were identified in a retrospective analysis. Baseline comorbidity and pulmonary function data for patients treated with curative radiotherapy (CurRT; biologically effective dose [BED]>58 Gy(10)) were abstracted by chart review. Kaplan-Meier and Cox regression were used to determine factors associated with overall survival (OS) and cause-specific survival (CSS) based on treatment group [no radiotherapy (NoRT), palliative radiotherapy (PallRT), or CurRT].

RESULTS

Of 1043 patients identified, approximately 1/3 received CurRT, and these patients had better performance status and lower stage disease than the other groups. There was a high prevalence of comorbid conditions in the CurRT group; 90% of CurRT patients had an age-adjusted Charlson comorbidity index (CCI) score ≥5. CurRT patients had a median survival 1-year longer than patients treated with PallRT or NoRT (p < 0.0001). In CurRT patients, CCI was predictive of OS (HR 1.1 per point CCI increase; p = 0.044), but not CSS. Patients receiving PallRT with a BED > 50 Gy(10) had significantly longer OS than those receiving PallRT of ≤50 Gy(10) (p < 0.0001).

CONCLUSIONS

Treatment of medically inoperable early stage NSCLC patients with CurRT is associated with a significantly longer survival, and for these patients CCI is a significant predictor of OS. For patients treated with PallRT, higher doses of palliative thoracic RT is associated with improved OS.

Comorbidity-adjusted survival in early stage lung cancer patients treated with hypofractionated proton therapy

Objective. To determine the influence of comorbidity on survival in early-stage lung cancer patients treated with proton radiotherapy, using the Charlson Comorbidity Index. Study Design and Setting. Fifty-four non-small-cell lung cancer patients, treated prospectively in a phase II clinical trial with hypofractionated proton therapy, were analyzed retrospectively to assess their burden of comorbid disease as expressed by Charlson Comorbidity Index. Using the Charlson Comorbidity Index method, a predicted survival curve based on comorbidity was formulated and compared to the observed mortality from causes other than lung cancer in the study population. Results. The study population had an average age score of 2.8 and an average Charlson Comorbidity Index of 4.7. Predicted survival was calculated to be 67% and 50% at 2 and 4 years, respectively. Actual comorbidity-specific survival at 2 and 4 years was 64% and 45%, respectively. The observed survival fell within the 95% confidence intervals of the predicted survival at all time points up to 5 years. Conclusion. Predicted mortality from concurrent disease, based on Charlson Comorbidity Index, correlated well with observed comorbidity-specific mortality. This helps substantiate the accuracy of the data coding in cause of death and strengthens previously reported disease-specific survival rates.

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

PURPOSE

To evaluate whether complex radiotherapy (RT) planning was associated with improved outcomes in a cohort of elderly patients with unresected Stage I-II non-small-cell lung cancer (NSCLC).

METHODS AND MATERIALS

Using the Surveillance, Epidemiology, and End Results registry linked to Medicare claims, we identified 1998 patients aged >65 years with histologically confirmed, unresected stage I-II NSCLC. Patients were classified into an intermediate or complex RT planning group using Medicare physician codes. To address potential selection bias, we used propensity score modeling. Survival of patients who received intermediate and complex simulation was compared using Cox regression models adjusting for propensity scores and in a stratified and matched analysis according to propensity scores.

RESULTS

Overall, 25% of patients received complex RT planning. Complex RT planning was associated with better overall (hazard ratio 0.84; 95% confidence interval, 0.75-0.95) and lung cancer-specific (hazard ratio 0.81; 95% confidence interval, 0.71-0.93) survival after controlling for propensity scores. Similarly, stratified and matched analyses showed better overall and lung cancer-specific survival of patients treated with complex RT planning.

CONCLUSIONS

The use of complex RT planning is associated with improved survival among elderly patients with unresected Stage I-II NSCLC. These findings should be validated in prospective randomized controlled trials.

High-dose proton therapy and carbon-ion therapy for stage I nonsmall cell lung cancer

BACKGROUND

A study was undertaken to evaluate the clinical outcome of particle therapy for stage I nonsmall cell lung cancer (NSCLC).

METHODS

From April 2003 to April 2007, 80 patients with stage I NSCLC were treated with proton therapy or carbon-ion therapy (57 with proton therapy and 23 with carbon-ion therapy) using 3 treatment protocols. In the first protocol, 80 gray equivalents (GyE) of proton therapy was given in 20 fractions, and the second proton therapy protocol used 60 GyE in 10 fractions. For carbon-ion therapy, 52.8 GyE was given in 4 fractions. After achieving promising preliminary results for the first protocol, the authors started to use the second proton therapy protocol to shorten the overall treatment time. Carbon-ion therapy was started in 2005, and thereafter, both proton and carbon-ion therapy plans were made for each patient, and the 1 that appeared superior was adopted. Patient age ranged from 48 to 89 years (median, 76 years). Thirty-seven patients were medically inoperable, and 43 refused surgery. Forty-two patients had T1 tumors, and 38 had T2 tumors.

RESULTS

The median follow-up period for living patients was 35.5 months. For all 80 patients, the 3-year overall survival, cause-specific survival, and local control rates were 75% (IA: 74%; IB: 76%), 86% (IA: 84%; IB: 88%), and 82% (IA: 87%; IB: 77%), respectively. There were no significant differences in treatment results among the 3 protocols. Grade 3 pulmonary toxicity was observed in only 1 patient.

CONCLUSIONS

Proton therapy and carbon-ion therapy are safe and effective for stage I NSCLC. Further investigation of particle therapy for stage I NSCLC is warranted.

Effectiveness of radiation therapy for elderly patients with unresected stage I and II non-small cell lung cancer

RATIONALE

Radiotherapy (RT) is considered the standard treatment for patients with stage I or II non-small lung cancer who are not surgical candidates because of comorbities or preferences against surgery.

OBJECTIVES

To compare the outcomes of patients treated with RT alone with those who were untreated to assess the effect of RT on survival.

METHODS

Using the Surveillance, Epidemiology and End Results (SEER) registry linked to Medicare files, we identified 6,065 unresected patients with histologically confirmed stage I and stage II non-small cell lung cancer, diagnosed between 1992 and 2002. We used propensity score methods and instrumental variable analysis to control for the possible effects of known as well as unmeasured confounders.

MEASUREMENTS AND MAIN RESULTS

Overall, 59% of patients received RT. The overall and lung cancer-specific survival of unresected patients treated with RT was significantly better compared with the untreated cases (P < 0.0001 for both comparisons). RT was associated with a 6-month improvement in median overall survival. Propensity score analyses showed that RT was associated with improved overall (hazard ratio, 0.74; 95% confidence interval, 0.70-0.78) and lung cancer-specific survival (hazard ratio, 0.73; 95% confidence interval, 0.69-0.78). Instrumental variable analysis also indicated improved outcomes among patients treated with RT.

CONCLUSIONS

RT improves survival of elderly patients with unresected stage I or II lung cancer. These results should be confirmed in prospective trials.

Stereotactic hypofractionated radiotherapy in stage I (T1-2 N0 M0) non-small-cell lung cancer (NSCLC)

Stereotactic Radiotherapy has the potential to produce high local control rates with low risk of severe lung toxicity. From December 2000 to January 2006, 68 inoperable patients (median age 76 years) with stage I NSCLC received definitive hSRT. A mean total dose of 37.5 Gy (24-40 Gy; 60%-isodose) in 3-5 fractions was applied. Immobilisation was carried out by means of a vacuum couch and low pressure foil (Medical Intelligence, Schwab München, Germany). Staging procedures were thoracic and abdominal CT-scan, FDG-PET and CT or MRI of the brain in all patients. Clinical target volume was the tumor as seen in lung windowing of CT and in FDG-PET. Organ movements (6-22 mm) and patient positioning in the couch (3-12 mm) were added as safety margin for the definition of the planning target volume (PTV), that was enclosed by the 60%-isodose. We observed four (6%) local tumor recurrences, resulting in an actuarial local tumor control rate of 96%, 88% and 88% after 1, 2 and 3 year follow-up. Nineteen patients died, with eight patients due to cancer (12%), two to local tumor progression alone. Cancer-specific survival is 96%, 82% and 73% at 1, 2 and 3 years. Eleven patients died from comorbidities, making a 53% overall 3-year survival. Fifty five percent of the patients were affected by mild acute and subacute side effects, with only 3% experiencing pneumonitis III degrees . Late effects were pneumonitis III degrees in 1%, rib fractures in 3%, and benign pleural effusion in 2 patients. Hypofractionated SRT is safe even in elderly patients with stage I NSCLC and significantly reduced lung capacity. It leads to high local control rates and should be offered to patients not amenable for curative resection.

The potential of proton beam radiation therapy in lung cancer (including mesothelioma)

A Swedish group of oncologists and hospital physicists have estimated the number of patients in Sweden suitable for proton beam therapy. The estimations have been based on current statistics of tumour incidence, number of patients potentially eligible for radiation treatment, scientific support from clinical trials and model dose planning studies and knowledge of the dose-response relations of different tumours and normal tissues. It is estimated that about 350 patients with lung cancer and about 20 patients with mesothelioma annually may benefit from proton beam therapy.

Proton therapy in lung cancer: clinical outcomes and technical issues. A systematic review

BACKGROUND AND PURPOSE

To determine whether, according to the currently available literature, proton therapy (PT) has a role in the treatment of non-small-cell lung cancer (NSCLC), to assess its safety and efficacy and to evaluate the main technical issues specifically related to this treatment technique.

MATERIALS AND METHODS

During March 2007, two independent researchers conducted a systematic review of the current data on the treatment of NSCLC with PT.

RESULTS

In total, 113 reports were retrieved, 17 of which were included in the analysis. There were no prospective trials (randomized or non-randomized). Nine uncontrolled single-arm studies were available from three PT centers, providing clinical outcomes for 214 patients in total. These reports were mainly related to stage I-II tumors, with results comparable to those obtained with surgery, without significant toxicity. In addition, two papers were found that compared photon and proton dose distributions, which showed a potential for dose escalation and/or a sparing of the organ at risk with PT. Finally, six studies analyzed dosimetric and technical issues related with PT, mainly underlining the difficulties in designing dose distributions that are representative of the dose actually delivered during treatment.

CONCLUSIONS

Although from a physical point of view PT is a good option for the treatment of NSCLC, limited data are available on its application in the clinical practice. Furthermore, the application of PT to lung cancer does present technical challenges. Because of the small number of institutions involved in the treatment of this disease, number of patients, and methodological weaknesses of the trials it is therefore not possible to draw definitive conclusions about the superiority of PT with respect to the photon techniques currently available for the treatment of NSCLC.

Regional hyperthermia combined with radiotherapy for locally advanced non-small cell lung cancers: a multi-institutional prospective randomized trial of the International Atomic Energy Agency

BACKGROUND

An International Atomic Energy Agency (IAEA)-sponsored, multi-institutional prospective randomized trial was conducted to clarify whether the combination of hyperthermia and radiotherapy improves the local response rate of locally advanced non-small cell lung cancer (NSCLC) compared with that obtained by radiotherapy alone.

METHODS

Between October 1998 and April 2002, 80 patients with locally advanced NSCLC were randomized to receive either standard radiation therapy alone (RT) or radiation therapy combined with hyperthermia (RT + HT). The primary endpoint was the local response rate. The secondary endpoints were local progression-free survival and overall survival.

RESULTS

The median follow-up period was 204 days for all patients and 450 days for surviving patients. There were no significant differences between the two arms with regard to local response rate (P = 0.49) or overall survival rate (P = 0.868). However, local progression-free survival was significantly better in the RT+HT arm (P = 0.036). Toxicity was generally mild and no grade 3 late toxicity was observed in either arm.

CONCLUSION

Although improvement of local progression-free survival was observed in the RT+HT arm, this prospective randomized study failed to show any substantial benefit from the addition of hyperthermia to radiotherapy in the treatment of locally advanced NSCLC.

Dose as a function of lung volume and planned treatment volume in helical tomotherapy intensity-modulated radiation therapy-based stereotactic body radiation therapy for small lung tumors

PURPOSE

To evaluate the limitations of Hi-Art Helical Tomotherapy (Middleton, WI) stereotactic body radiotherapy (SBRT) for lung lesions, and to provide an initial report on patients treated with this method. Stereotactic body radiotherapy was shown to be an effective, well-tolerated treatment for early-stage, non-small-cell lung carcinoma (NSCLC). The Radiation Therapy Oncology Group (RTOG) 0236 protocol is currently evaluating three-dimensional conformal SBRT that delivers 60 Gy in three fractions.

METHODS AND MATERIALS

Inverse treatment planning for hypothetical lung gross tumor volumes (GTV) and planned treatment volume (PTV) expansions were performed. We tested the hypothesis that the maximum acceptable dose (MAD) to be delivered to the lesion by SBRT could be predicted by PTV and lung volume. Dose constraints on normal tissue were as designated by the RTOG protocol. Inverse planning was performed to find the maximum tolerated SBRT dose up to 60 Gy.

RESULTS

Regression analysis of the data obtained indicated a linear relationship between MAD, PTV, and lung volume. This generated two equations which may be useful predictive tools. Seven patients with Stage I and II NSCLC treated at the University of Virginia with this method tolerated the treatment extremely well, and suffered no greater than grade I toxicity, with no evidence of disease recurrence in follow-up from 2-20 months.

CONCLUSIONS

Helical tomotherapy SBRT for lung lesions is well-tolerated. In addition, the likely MAD for patients considered for this type of treatment can be predicted by PTV and lung volume.

Current status of radiotherapy with proton and light ion beams

Several model studies have shown potential clinical advantages with charged particles (protons and light ions) compared with 3D-conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT) in many disease sites. The newly developed intensity-modulated proton therapy (IMPT) often yields superior dose distributions to photon IMRT, with the added advantage of a significant reduction in the volume of healthy normal tissues exposed to low-to-medium doses. Initially, the major emphasis in clinical research for proton and light ion therapy was dose escalation for inherently radioresistant tumors, or for lesions adjacent to critical normal structures that constrained the dose that could be safely delivered with conventional x-ray therapy. Since the advent of IMRT the interest in particle therapy has gradually shifted toward protocols aimed at morbidity reduction. Lately the emphasis has mostly been placed on the potential for reduced risk of radiation-induced carcinogenesis with protons. Compared with 3D-CRT, a 2-fold increase has been theoretically estimated with the use of IMRT due to the larger integral volumes. In the pediatric setting, due to a higher inherent susceptibility of tissues, the risk could be significant, and the benefits of protons have been strongly emphasized in the literature. There is a significant expansion of particle therapy facilities around the world. Increasing public awareness of the potential benefits of particle therapy and wider accessibility for patients require that treating physicians stay abreast of the clinical indications of this radiotherapy modality. The article reviews the available literature for various disease sites in which particle therapy has traditionally been considered to offer clinical advantages and to highlight current lines of clinical research. The issue of radiation-induced second malignancies is examined in the light of the controversial epidemiological evidence available. The cost-effectiveness of particle therapy is also discussed.

Effect of Histologic Type on Recurrence Pattern in Radiation Therapy for Medically Inoperable Patients with Stage I Non-Small-Cell Lung Cancer

Japanese randomized trials showed that there was a significant impact on survival from stage I adenocarcinoma (AD) of the lung by adjuvant chemotherapy with uracil-tegaful after complete resection but there was no effect for patients with squamous cell carcinoma (SQ). The purpose of this study was to examine the correlation of tumor histology and clinical outcome of radiation therapy (RT) for stage I non-small-cell lung cancer (NSCLC) and to consider the necessity of adjuvant chemotherapy after RT for these patients. The subjects were 83 patients, 54 with SQ and 29 with AD; they had received definitive RT with the total dose ranging from 60 to 80 Gy with conventional fractionation at a daily dose of 2 Gy. The differences between SQ and AD with respect to survival and recurrence pattern were investigated. The 5-year overall survival and cause-specific survival rates were 26.5% and 49.1%, respectively. No difference in survival was observed between SQ and AD patients, and the recurrence rates were almost identical (44% for SQ and 45% for AD). However, the 5-year primary control rate of SQ was significantly poorer than that of AD (SQ: 61.5%; AD: 87.6%; p = 0.03). Conversely, the 5-year metastasis-free survival rate of SQ was significantly better than that of AD (SQ: 88.2%; AD: 53.0%; p = 0.005). The different failure pattern, according to tumor histology, indicates that taking into consideration the difference in their clinical behaviors would also be important for planning RT and surgery for early lung cancer.

Absence of toxicity with hypofractionated 3-dimensional radiation therapy for inoperable, early stage non-small cell lung cancer

Purpose

Hypofractionated radiotherapy may overcome repopulation in rapidly proliferating tumors such as lung cancer. It is more convenient for the patients and reduces health care costs. This study reports our results on patients with medically inoperable, early stage, non-small cell lung cancer (NSCLC) treated with hypofractionation.

Materials and methods

Stage T1-2N0 NSCLC patients were treated with hypofractionation alone, 52.5 Gy/15 fractions, in 3 weeks, with 3-dimensional conformal planning. T1-2N1 patients with the hilar lymphnode close to the primary tumor were also eligible for this treatment. We did not use any approach to reduce respiratory motion, but it was monitored in all patients. Elective nodal radiotherapy was not performed. Routine follow up included assessment for acute and late toxicity and radiological tumor response. Median follow up time was 29 months for the surviving patients.

Results

Thirty-two patients with a median age of 76 years, T1 = 15 and T2 = 17, were treated. Median planning target volume (PTV) volume was 150cc and median V16 of both lungs was 13%. The most important finding of this study is that toxicity was minimal. Two patients had grade ≤ 2 acute pneumonitis and 3 had mild (grade 1) acute esophagitis. There was no late toxicity. Actuarial 1 and 2-year overall survival rates are 78% and 56%, cancer specific survival rates (CSS) are 90% and 74%, and local relapse free survival rates are 93% and 76% respectively.

Conclusion

3-D planning, involved field hypofractionation at a dose of 52.5 Gy in 15 daily fractions is safe, well tolerated and easy radiation treatment for medically inoperable lung cancer patients. It shortens by half the traditional treatment. Results compare favorably with previously published studies. Further studies are needed to compare similar technique with other treatments such as surgery and stereotactic radiotherapy.

Pretreatment prognostic factors in patients with early-stage (I/II) non–small-cell lung cancer treated with hyperfractionated radiation therapy alone

PURPOSE

To investigate influence of various pretreatment prognostic factors in patients with early stage (I/II) non-small-cell lung cancer (NSCLC) treated with hyperfractionated radiation therapy alone.

PATIENTS AND METHODS

One hundred and sixteen patients were treated with tumor doses of 69.6 Gy, 1.2-Gy, twice-daily fractionation. There were 49 patients with Stage I and 67 patients with Stage II. Eighty patients had Karnofsky performance status (KPS) 90-100 and 95 patients had <5% weight loss. Peripheral tumors were observed in 57 patients. Squamous histology was observed in 70 patients and the majority of patients had concomitant disease (n=72).

RESULTS

The median survival time for all patients was 29 months; 5-year survival was 29%. The median time to local progression and the distant metastasis were not achieved, whereas 5-year local progression-free and distant metastasis-free survivals were 50% and 72%, respectively. Multivariate analysis identified KPS, weight loss, location, histology, and the reason for not undergoing surgery as prognostic factors for survival. KPS, location, and histology influenced local progression-free survival, whereas only KPS and weight loss influenced distant metastasis-free survival.

CONCLUSIONS

This retrospective analysis identified KPS and weight loss as the most important prognostic factors of outcome in patients with early-stage NSCLC treated with hyperfractionation radiation therapy.

PET/CT Imaging of Lung Cancer

Fluoro-deoxyglucose positron emission tomography (PET) imaging has a diagnostic and prognostic value in the initial staging, restaging, and surveillance of non-small-cell lung cancer (NSCLC). When used in conjunction with conventional radiologic imaging, PET imaging has been shown to result in significant changes in clinical management of NSCLC. Specifically, baseline PET imaging can improve initial staging and guide surgical and radiotherapy planning, whereas repeat PET imaging after the initiation of chemoradiotherapy can predict tumor response and help tailor therapy. After the end of definitive treatment, PET has greater diagnostic accuracy than other imaging modalities for the detection of tumor recurrence. The recent development of fused PET/CT imaging has improved the radiologic evaluation of NSCLC patients by combining metabolic and anatomic imaging; however, this has resulted in more complexity in the image interpretation. It is important for the interpreting physician to understand the role PET/CT plays in the staging, assessment of treatment, and follow-up after therapy in the multidisciplinary management of patients with NSCLC.

Biologic effects of radiofrequency thermal ablation on non–small cell lung cancer: Results of a pilot study

OBJECTIVES

Radiofrequency ablation of lung tumors is an emerging technique with promising results. To achieve more information on its effects on pulmonary parenchyma and primary tumors, and to assess its efficacy in determining complete necrosis of the lesion, we led a pilot study consisting of thermal ablation followed by surgical resection.

METHODS

Ten patients with early stage non-small cell lung cancer were enrolled in the study. In 5 patients radiofrequency ablation was achieved through thoracotomy just before the surgical resection. In another 5 patients radiofrequency ablation was performed percutaneously, under computed tomography guidance, and the surgical resection was performed after 15 days.

RESULTS

Nine of the 10 patients enrolled in the study were available for analysis. There were 8 men and 1 woman with a mean age of 65.5 years. In all cases histologic diagnosis was available before radiofrequency ablation; adenocarcinoma was identified in 5 patients, and squamous cell carcinoma was identified in 4 patients. Microscopic examination showed complete necrosis of the tumor in 6 of 9 cases. No anatomopathologic alterations were seen in surrounding distant parenchyma.

CONCLUSIONS

Our study confirms the safety of radiofrequency ablation, particularly underlining the possibility of performing a thermal lesion in the lung in a controlled manner. It also assesses that radiofrequency ablation may be effective in the local control of primary lung cancer. However, surgery still represents the mainstay of treatment of non-small cell lung cancer, and radiofrequency ablation must be reserved for high-risk patients.

The Role of Radiation Therapy in Thoracic Tumors

Radiation plays an important role in the treatment of thoracic tumors. During the last 10 years there have been several major advances in thoracic RT including the incorporation of concurrent chemotherapy and the application of con-formal radiation-delivery techniques (eg, stereotactic RT, three-dimensional conformal RT, and intensity-modulated RT) that allow radiation dose escalation. Radiation as a local measure remains the definitive treatment of medically inoperable or surgically unresectable disease in NSCLC and part of a multimodality regimen for locally advanced NSCLC, limited stage SCLC, esophageal cancer, thymoma, and mesothelioma.

High-dose proton beam therapy for Stage I non-small-cell lung cancer

PURPOSE

To evaluate retrospectively the safety and efficacy of high-dose proton beam therapy (PBT) for Stage I non-small-cell lung cancer (NSCLC).

METHODS AND MATERIALS

Between 1999 and 2003, 37 patients were treated in our institution. The indications for PBT were pathologically proven NSCLC, clinical Stage I, tumor size < or =5 cm, medically inoperable or refusal of surgery, and written informed consent. A total dose of 70-94 Gy(E) was delivered in 20 fractions (3.5-4.9 Gy(E) per fraction).

RESULTS

Patient characteristics (number of patients) were as follows: Stage IA/IB, 17 of 20; medically inoperable/refusal of surgery, 23/14; total dose 70/80/88/94 Gy(E), 3/17/16/1. With a median follow-up period of 24 months, the 2-year local progression-free and overall survival rates were 80% and 84%, respectively. The 2-year locoregional relapse-free survival rates in Stage IA and Stage IB were 79% and 60%, respectively. No serious acute toxicity was observed. Late Grades 2 and 3 pulmonary toxicities were observed in 3 patients each. Of these 6 patients, 5 had Stage IB disease.

CONCLUSIONS

Proton beam therapy is a promising treatment modality for Stage I NSCLC, though locoregional relapse and late pulmonary toxicities in Stage IB patients were substantial. Further investigation of PBT for Stage I NSCLC is warranted.

Imaging of the Patient with Non–Small Cell Lung Cancer

Lung cancer is the most common type of cancer and is the leading cause of cancer deaths in the United States for both men and women. Even though the 5-year survival rate of patients with lung cancer remains dismal at 14% for all cancer stages, treatments are improving and newer agents for lung cancer appear promising. Therefore, an accurate assessment of the extent of disease is critical to determine whether the patient is treated with surgical resection, radiation therapy, chemotherapy, or a combination of these modalities. Radiologic imaging plays an important role in the staging evaluation of the patient; however, radiologists need to be aware that there are also important differences in what each specialist needs from imaging to provide appropriate treatment. This article reviews the role of imaging in patients with non-small cell lung cancer, with an emphasis on the radiologic imaging findings relevant for each specialty.

Concurrent hyperfractionated radiotherapy and low-dose daily carboplatin/paclitaxel in patients with early-stage (I/II) non-small-cell lung cancer: long-term results of a phase II study

PURPOSE

Feasibility and activity of concurrent hyperfractionated radiotherapy (Hfx RT) and low-dose, daily carboplatin and paclitaxel were investigated in patients with early-stage (I/II) non-small-cell lung cancer in a phase II study.

PATIENTS AND METHODS

Fifty-six patients started their treatment on day 1 with 30 mg/m2 of paclitaxel. Hfx RT using 1.3 Gy bid to a total dose of 67.6 Gy and concurrent low-dose daily carboplatin 25 mg/m2 and paclitaxel 10 mg/m2, both given Mondays through Fridays during the RT course, started from the second day.

RESULTS

There were 29 complete responses (52%) and 15 partial responses (27%), and 12 patients (21%), experienced stable disease. The median survival time was 35 months, and 3- and 5-year survival rates were 50% and 36%, respectively. The median time to local progression has not been achieved, but 3- and 5-year local progression-free survival rates were 56% and 54%, respectively. The median time to distant metastasis has not been achieved, but 3- and 5- year distant metastasis-free survival rates were 61% and 61%, respectively. The median and 5-year cause-specific survivals were 39 months and 43%, respectively. Acute high-grade (> 3) toxicity was hematologic (22%), esophageal (7%), or bronchopulmonary (7%). No grade 5 toxicity was observed. Late high-grade toxicity was rarely observed (total, 10%).

CONCLUSION

Hfx RT and concurrent low-dose daily carboplatin/paclitaxel was feasible with low toxicity and effective in patients with stage I/II non-small-cell lung cancer. It should continue to be investigated for this disease.

Radiation Therapy for the Treatment of Unresected Stage I-II Non-small Cell Lung Cancer

STUDY OBJECTIVES

Radiotherapy is considered to be the standard treatment for patients with stage I or II non-small lung cancer who refuse surgery or who are not surgical candidates because of significant comorbidities. To determine whether radiotherapy benefits these patients, we compared the survival of those treated with radiation alone to those left untreated.

METHODS

Using the Surveillance, Epidemiology, and End Results registry, we identified all patients in whom histologically confirmed, stage I and II non-small cell lung cancer had been diagnosed between 1988 and 2001. Among these patients, 4,357 did not undergo surgical resection. Kaplan-Meier survival curves were compared among patients who received and who did not receive radiation therapy. We used Cox regression analysis to evaluate the effect of radiation on survival after adjusting for potential confounders.

RESULTS

The survival of patients with lung cancer who did not undergo resection and had been treated with radiation therapy was significantly better compared to the untreated patients (stage I cancer, p = 0.0001; stage II cancer, p = 0.001). The median survival time of patients with stage I disease who underwent radiotherapy was 21 months compared to 14 months for untreated patients. Stage II patients who received and did not receive radiation therapy had median survival times of 14 and 9 months, respectively. The survival of treated and untreated patients was not significantly different approximately 5 years after diagnosis (stage I disease, 15% vs 14%, respectively; stage II disease, 11% vs 10%, respectively). In multivariate analysis, radiation therapy was significantly associated with improved lung cancer survival after controlling for age, sex, race, and tumor histology.

CONCLUSIONS

These results suggest that radiotherapy is associated with improved survival in patients with unresected stage I or II non-small cell lung cancer. The observed improvement in median survival time was only 5 to 7 months, and radiotherapy did not offer the possibility of a cure.

Imaging of non-small cell lung cancer

Radiologic evaluation is an important component of the clinical staging evaluation of lung cancer and can greatly influence whether the patient is treated with surgical resection, radiation therapy, chemotherapy, or a combination of these modalities. In addition to staging, the radiologic evaluation of the patient undergoing treatment and subsequent follow-up is important to the clinician for assessing treatment effects and complications. This article discusses the imaging of patients with non-small cell lung cancer and its use in management of these patients.

Nonsurgical Therapy for Stages I and II Non–Small Cell Lung Cancer

For patients who have stages I and II non-small cell lung cancer (NSCLC) and who are unable or unwilling to undergo surgical resection, nonsurgical treatment modalities have been used with curative intent. Conventionally fractionated radiotherapy has been the mainstay of nonsurgical therapy; however, advances in technology and the clinical application of radiobiologic principles have allowed more accurately targeted treatment that delivers higher effective doses to the tumor, while respecting the tolerance of surrounding normal tissues. This article discusses nonsurgical approaches to the treatment of early-stage NSCLC, including several promising techniques, such as radiation dose escalation, altered radiation fractionation, stereotactic radiotherapy, and radiofrequency ablation.

Hypofractionated proton beam radiotherapy for stage I lung cancer

STUDY OBJECTIVES

To determine the efficacy and toxicity of high-dose hypofractionated proton beam radiotherapy for patients with clinical stage I lung cancer.

DESIGN

A prospective phase 2 clinical trial.

SETTING

Loma Linda University Medical Center.

PATIENTS

Subjects with clinical stage I non-small cell lung cancer who were medically inoperable or refused surgery.

INTERVENTIONS

All patients were treated with proton beam radiotherapy. The target included the gross tumor volume as seen on CT scan, with additional margin to allow for respiratory motion. A multibeam treatment plan was generated. Delivered treatment was 51 cobalt Gray equivalent (CGE) in 10 fractions over 2 weeks to the initial 22 patients; the subsequent 46 patients received 60 CGE in 10 fractions over 2 weeks.

RESULTS

Sixty-eight patients were analyzed for this report, with a median follow-up time of 30 months. No cases of symptomatic radiation pneumonitis or late esophageal or cardiac toxicity were seen. The 3-year local control and disease-specific survival rates were 74%, and 72%, respectively. There was significant improvement in local tumor control in T1 vs T2 tumors (87% vs 49%), with a trend toward improved survival. Cox regression analysis revealed that patients with higher performance status, female gender, and smaller tumor sizes had significantly improved survival.

CONCLUSION

High-dose hypofractionated proton beam radiotherapy can be administered safely, with minimal toxicity, to patients with stage I lung cancer. Local tumor control appears to be improved when compared to historical results utilizing conventional radiotherapy, with a good expectation of disease-specific survival 3 years following treatment.