Prophylactic cranial irradiation revisited: cost-effectiveness and quality of life in small-cell lung cancer

Limited-Stage Small-Cell Lung Cancer Treated with Early Chemo-Radiotherapy: The Impact of Effective Chemotherapy

Aims and Background

Small cell lung cancer is characterized by an aggressive clinical course and a high sensitivity to both chemotherapy and radiotherapy. We present the Florence University experience in concurrent early radio-chemotherapy in patients affected by limited-stage small cell lung cancer, with particular emphasis on treatment safety, disease outcome and prognostic factors.

Methods and Study Design

Fifty-seven patients were treated between June 2000 and February 2005. All patients underwent platinum-based chemotherapy, administered intravenously following two different regimens, for at least three cycles. Eighteen patients (31.6%) received epirubicin and ifosfamide in 3-week cycles alternating with etoposide and cisplatin, administered on day 1 to 3; 39 patients (68.4%) received etoposide and cisplatin. A total of 6 cycles were planned. Radiotherapy was administered concurrently to the first cycle of etoposide and cisplatin.

Results

Clinical stage (P = 0.036) and number of chemotherapy courses (P = 0.009) emerged as the only significant death predictors at univariate analysis. Number of chemotherapy courses persisted as a significant death predictor also at multivariate regression analysis, with a reduced death risk for 5–6 chemotherapy cycles in comparison to 3–4 cycles (hazard ratio, 0.44). At a mean follow up of 38.5 months (standard deviation, 3.24 years; range, 6–164 months), considering the best overall tumor response achieved at any time during the whole treatment period, we obtained 32 complete responses (56.1%), 23 partial responses (40.3%) and 2 stable diseases.

Conclusions

Our analysis showed that concurrent early radio-chemotherapy in limited-stage small cell lung cancer treatment represents a safe and effective approach in patients. We confirmed the relevant impact on overall survival of effective chemotherapy delivery.

Treatment for small cell lung cancer, where are we now?-a review

Small cell lung cancer (SCLC) represents between 13% and 15% of all diagnosed lung cancers worldwide. It is an aggressive neoplasia, with a 5-year mortality of 90% or more. It has historically been classified as limited disease (LD) and extensive disease (ED) in most study protocols. The cornerstone of treatment for any stage of SCLC is etoposide-platinum based chemotherapy; in limited stage (LS), concomitant radiotherapy to thorax and mediastinum. Prophylactic radiotherapy to the central nervous system (CNS) [prophylactic cerebral irradiation (PCI)] has diminished the incidence of brain metastasis as the site for relapse in LD and ED patients, therefore it should be offered to patients with complete response to induction first-line treatment. Regarding second-line treatment, results are more modest and topotecan is accepted as treatment for this scenario offering a modest benefit.

Multimodality Therapy for Limited-Stage Small-Cell Lung Cancer

Limited-stage small-cell lung cancer (SCLC) occurs in only one third of patients with SCLC, but it is potentially curable. Combined-modality therapy (chemotherapy and radiotherapy) has long been the mainstay of therapy for this condition, but more recent data suggest a role for surgery in early-stage disease. Prophylactic cranial irradiation seems to improve outcomes in patients who have responded to initial therapy. This review addresses the practical aspects of staging and treatment of patients with limited-stage SCLC.

Cost-effectiveness of chemotherapy combined with thoracic radiotherapy versus chemotherapy alone for limited stage small cell lung cancer: A population-based propensity-score matched analysis

BACKGROUND

The addition of thoracic radiotherapy improves the outcome of limited stage small cell lung cancer (LS-SCLC), however, the cost-effectiveness of this process has never been reported. We aimed to estimate the short-term cost-effectiveness of chemotherapy combined with thoracic radiotherapy (C-TRT) versus chemotherapy alone (C/T) for LS-SCLC patients from the payer's perspective (Taiwan National Health Insurance).

METHODS

We identified LS-SCLC patients diagnosed within 2007-2009 through a comprehensive population-based database containing cancer and death registries, and reimbursement data. The duration of interest was one year within diagnosis. We included potential confounding covariables through literature searching and our own experience, and used a propensity score to construct a 1:1 population for adjustment. We used a net benefit (NB) approach to evaluate the cost-effectiveness at various willingness-to-pay (WTP) levels. Sensitivity analysis regarding potential unmeasured confounder(s) was performed.

RESULTS

Our study population constituted 74 patients. The mean cost (2013 USD) and survival (year) was higher for C-TRT (42 439 vs. 28 357; 0.94 vs. 0.88). At the common WTP level (50 000 USD/life-year), C-TRT was not cost effective (incremental NB - 11 082) and the probability for C-TRT to be cost effective (i.e. positive net benefit) was 0.005. The result was moderately sensitive to potential unmeasured confounder(s) in sensitivity analysis.

CONCLUSIONS

We provide evidence that when compared to C/T, C-TRT is effective in improving survival, but is not cost-effective in the short-term at a common WTP level from a payer's perspective. This information should be considered by clinicians when discussing thoracic radiotherapy with their LS-SCLC patients.

Quality-adjusted time without symptoms or toxicity (Q-TWiST): patient-reported outcome or mathematical model? A systematic review in cancer

OBJECTIVE

Successful cancer treatment is defined as an increase in overall survival and/or progression-free survival. Despite their importance, these metrics omit patient quality of life. Quality-adjusted time without symptoms or toxicity (Q-TWiST) was developed to adjust survival gained, accounting for quality of life. The purpose of this systematic review was to assess the methods reported in cancer literature to determine Q-TWiST values and how these are currently translated to the clinic.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines were used to conduct a systematic review of studies indexed on MEDLINE and Web of Science through April 2013. Cancer studies that measured Q-TWiST either as a primary outcome or retrospectively and determined utility coefficients from a patient population were identified, and their methods reviewed to determine how the utility coefficient was calculated. Additionally, other relevant factors such as definitions of health states and significant findings were collected and summarized.

RESULTS

Out of 284 studies, 11 were identified that calculated patient-defined utility coefficients. Several methods to determine utility coefficients were reported, and multiple definitions of health state toxicity were applied. Of these studies, seven reported significant differences (p < 0.05) in quality-adjusted survival. No studies, however, directly discussed the clinical relevance of their findings.

CONCLUSIONS

Currently, Q-TWiST is utilized as a mathematical theory rather than a clinical tool. Standardization of terminology plus reliability and validity testing of determining both utility coefficients and time frame definitions must be performed before Q-TWiST can become clinically useful to physicians and patients alike for making treatment decisions.

Cost-effectiveness studies in radiation therapy

The field of radiation therapy has made dramatic technical advances over the past 20 years. 3D conformal radiotherapy, intensity-modulated radiation therapy and proton beam therapy have all been developed in an attempt to improve the therapeutic ratio: higher cure rates with lower toxicity. Unfortunately, although the costs of radiation therapy are certainly increasing, it is unclear whether its clinical benefit has also improved. Cost-effectiveness analyses are designed to formally evaluate the cost of a treatment relative to an associated change in quality-adjusted survival. As the cost of oncologic care is increasing, it is critically important to assess the cost-effectiveness of radiation therapy. This article will describe the issues surrounding the delivery and cost of radiation therapy, and it will summarize the work that has been done to evaluate the use of cost-effectiveness in radiation oncology.

Prophylactic cranial irradiation in patients with small-cell lung cancer: the experience at the Institute of Oncology Ljubljana

Background

Prophylactic cranial irradiation (PCI) has been used in patients with small-cell lung cancer (SCLC) to reduce the incidence of brain metastases (BM) and thus increase overall survival. The aim of this retrospective study was to analyze the characteristics of patients with SCLC referred to the Institute of Oncology Ljubljana, their eligibility for PCI, patterns of dissemination, and survival.

Patients and methods

Medical charts of 357 patients with SCLC, referred to the Institute of Oncology Ljubljana between January 2004 and December 2006, were reviewed to determine characteristics of patients chosen for PCI. The following data were collected: age, gender, performance status (PS), extent of the disease, smoking status, type of primary treatment with outcome, haematological and biochemical parameters, PCI use, and finally brain metastases (BM) status at diagnoses and after treatment.

Results

PCI was performed in 24 (6.7%) of all patients. Six (25%) patients developed brain metastases after they were treated with PCI. Brain was the only site of metastases in 4 patients, two progressed to multiple organs. Median overall survival of patients with PCI was 21.9 months, without PCI 12.13 months (p = 0.004). From the collected data there were good prognostic factors: age under 65 years, limited disease (LD), performance status, normal levels of lactate dehydrogenase (LDH) and normal levels of C-reactive protein levels (CRP). Other prognostic factors did not show statistical significant values.

Conclusions

Survival of patients with LD, who have had PCI, was significantly better than those who had not. We decided to perform PCI in patients with LD, in those with complete or near complete response, and those with good performance status (≥ 80). We did not use PCI in extended disease (ED). The reason for that shall be addressed in the future. Doses for PCI were not uniform, therefore more standard approach should be considered.

Limited-stage small-cell lung cancer: the current status of combined-modality therapy

Limited-stage (LS) small-cell lung cancer (SCLC) remains a therapeutic challenge to medical and radiation oncologists. The treatment of LS-SCLC has evolved significantly over the last two decades with combined-modality therapy now the standard of care. The addition of thoracic radiotherapy (TRT) to standard chemotherapy has led to improvements in long-term survival in this population. However, many questions remain about the optimal way to deliver chemoradiotherapy. In a landmark trial, twice-daily TRT to a dose of 45 Gy increased 5-year survival by 10% compared with once-daily TRT administered to the same dose. This suggests that more intensive TRT regimens may lead to further survival gains, assuming they can be delivered safely in this setting. Strategies currently under investigation include higher total daily doses delivered once daily or novel concurrent boost techniques allowing more intensive treatments over shorter periods of time. Several trials and meta-analyses have evaluated the timing of TRT with chemotherapy, with the weight of evidence suggesting that early and concurrent TRT with chemotherapy is optimal. Novel cytotoxic chemotherapy combinations have failed thus far to provide an advantage over standard etoposide-cisplatin combinations. Prophylactic cranial irradiation in near or complete responders to induction chemoradiotherapy has also been shown to improve long-term survival rates. LS-SCLC has been a model cancer in terms of the potential benefit of combined chemoradiotherapy strategies in improving patient outcomes.

Tolerability of accelerated chest irradiation and impact on survival of prophylactic cranial irradiation in patients with limited-stage small cell lung cancer: review of a single institution's experience

INTRODUCTION

Evidence that has been published in the last decade indicates that in patients with limited-stage small-cell lung cancer (SCLC), hyperfractionated accelerated thoracic radiotherapy (RT) given twice daily and prophylactic cranial irradiation (PCI) have each separately improved survival. Concerns about the toxicities associated with these treatments and uncertainty about their impact on survival outside the trial setting may have restricted the extent to which they have been incorporated into standard treatment protocols. We have reviewed the experience at Peter MacCallum Cancer Centre to determine the tolerability of these treatments in routine practice and to determine their effects on survival.

METHODS

A retrospective review of patients with limited-stage SCLC receiving a radical course of thoracic RT between June 1998 and May 2002, including either conventional fractionation at 50 Gy for 5 weeks, or hyperfractionated accelerated RT at 45 Gy for 3 weeks. Patients achieving a complete response were offered PCI at 36 Gy in 18 fractions. The main outcomes recorded were RT toxicity (graded using CTCAE v. 3.0 and RTOG/EORTC late scoring criteria), response, relapse-free survival, and overall survival.

RESULTS

Ninety patients were identified as having undergone radical-intent thoracic RT, with a median potential follow-up of 4.2 years. Fifty-seven patients (63%) were treated with hyperfractionated accelerated RT, and 33 (37%) were treated with conventional fractionation. Forty-six patients (51%) received PCI. Patients receiving hyperfractionated accelerated RT compared with conventional fractionation had higher rates of grade 3 and 4 esophagitis (14% versus 6%; p = 0.312), a higher rate of treatment interruptions (12% versus 3%; p = 0.250), and a higher hospital admission rate (39% versus 15%; p = 0.031). The majority of patients were able to complete the planned treatment, and there were no treatment-related deaths. Median survival for all patients from commencement of RT was 14.2 months (95% confidence interval [CI]: 11.9-18.1 months), and survival at 2 years was 24.8% (95% CI: 16.9-35.0%). On multifactor analysis, the only factor associated with longer survival was PCI (hazard ratio = 0.40; p < 0.001).

CONCLUSIONS

Hyperfractionated accelerated RT was more toxic than conventional fractionation, but it was possible to deliver treatment as planned in the majority of patients. PCI was associated with improved survival. Both treatments can be incorporated into routine practice.

Small cell lung cancer: treatment review

Lung cancer was relatively uncommon at the turn of the 20th century, and has increased in prevalence at alarming rates, particularly because of the augmented trend in smoking, so that it is now the most common cause of cancer death in the world. As almost a quarter of these cancers are of small cell in origin, it seems only appropriate that small cell lung cancer receives ample attention, rather than seemingly to have been overlooked over the last 10-15 years. Despite its generally late presentation and high risk of dissemination, it is exceptionally sensitive to chemo-radiotherapy. This review looks at the diverse options of treatment that have been used over the last few years and tries to highlight the best available. As more than 50% of patients diagnosed with lung cancer are over 70 years of age and various studies have shown that older people respond just as well as their younger counterparts, with similar results in response rates, toxicity and outcomes, it is imperative that the older generation are not disregarded in terms of age being a contraindication to therapy.

Decision Analysis for Prophylactic Cranial Irradiation for Patients With Small-Cell Lung Cancer

Purpose

Prophylactic cranial irradiation (PCI) has been shown to provide survival benefit in patients with limited disease small-cell lung cancer (LD-SCLC) who have achieved complete response. However, PCI may also produce long-term neurotoxicity (NT). The benefits and risks of PCI in LD-SCLC are evaluated.

Methods

We developed a decision-analytic model to compare quality-adjusted life expectancy (QALE) in a cohort of SCLC patients who do or do not receive PCI by varying survival rates and the frequency and severity of PCI-related NT. Sensitivity analyses were applied to examine the robustness of the optimal decision.

Results

At current published survival rates (26% 5-year survival rate with PCI and 22% without PCI) and a low NT rate, PCI offered a benefit over no PCI (QALE = 4.31 and 3.70 for mild NT severity; QALE = 4.09 and 3.70 for substantial NT severity, respectively). With a moderate NT rate, PCI was still preferred. If the PCI survival rate increased to 40%, PCI outperformed no PCI with a mild NT severity. However, no PCI was preferred over PCI (QALE = 5.72 v 5.47) with substantial NT severity. Two-way sensitivity analyses showed that PCI was preferred for low NT rates, mild NT severity, and low long-term survival rates. Otherwise, no PCI was preferred.

Conclusion

The current data suggest PCI offers better QALE than no PCI in LD-SCLC patients who have achieved complete response. As the survival rate for SCLC patients continues to improve, NT rate and NT severity must be controlled to maintain a favorable benefit-risk ratio for recommending PCI.

Analyzing oncology clinical trial data using the Q-TWiST method: clinical importance and sources for health state preference data

PURPOSE

The Quality-adjusted Time Without Symptoms of disease and Toxicity (Q-TWiST) analysis method is frequently applied to evaluating outcomes in cancer clinical trials, but there is little information on what constitutes a clinically important difference (CID). We reviewed the Q-TWiST, health-related quality of life (HRQL) and utility measurement literature to develop recommendations for CID for the Q-TWiST. We also provide recommendations for measuring health utilities and for the design of Q-TWiST studies.

METHODS

The English language literature was searched between 1986 and 2003 for Q-TWiST studies in oncology. We estimated the percent differences between treatments based on median follow-up duration for overall, progression-free and quality-adjusted survival. We also reviewed the relevant HRQL and utility literature on clinical importance.

RESULTS

The overall differences between treatments for most (56%) of the observed, published values for Q-TWiST analyses ranged between 12% and 19%. Three-fourths of the Q-TWiST studies had gains in survival of 12%-17%, while differences in progression-free survival ranged from 12% to 26%. Studies that have evaluated the clinical importance of changes in HRQL scores suggest that changes of 5%-10% are clinically meaningful, and other research suggests that 0.5 standard deviation is a reasonable threshold for changes in HRQL for chronic diseases. Similarly, one guideline from the health state utility literature is that a 5%-10% difference in standard gamble utility scores is clinically important. Various sources are available for health utilities for Q-TWiST studies and the most valid are derived from patients or the general public, although most studies rely on sensitivity analyses with no collection of utilities.

CONCLUSIONS

We recommend that the CID for Q-TWiST is 10% of overall survival in a study, and differences of 15% are clearly clinically important. If less is known about a specific treatment and/or disease area, the CID should be greater than 5% but not more than 10% in planning sample size and statistical power. These CID estimates should be interpreted with caution, pending confirmation in future studies by direct patient assessment of the clinically relevant health states for Q-TWiST.

Treating brain metastases: current approaches and future directions

Brain metastases frequently present with neurologic signs or symptoms in a patient with a history of cancer. The finding of a brain metastasis is usually associated with terminal disease. However, patients with brain metastases are a heterogeneous group. Therefore, the treatment of brain metastases must be tailored to each individual patient. In this article, which patients with brain metastases benefit from surgical resection, radiosurgery and whole-brain radiation therapy are reviewed. Reports of treating patients with brain metastases with chemotherapy are also reviewed and data that supports prophylactic treatment of the brain for select patients is discussed. This review aims to provide a framework for treating patients with different presentations of brain metastases and to highlight important avenues for future research.

A meta-analysis of the timing of chest irradiation in the combined modality treatment of limited-stage small cell lung cancer

The objective of this study was to determine whether initial combined chemoradiation results in superior 1-, 2-, and 3-year survivals in the treatment of limited-stage small cell lung cancer versus sequential or split-course therapy. Using a prospective meta-analysis protocol outlining study inclusion criteria, literature search strategy, and statistical procedures, data from all available randomized controlled trials addressing the above-noted objective were pooled using a fixed effects model (Peto). Results were expressed as summary odds ratios (ORp), and statistical tests for data heterogeneity were performed prior to calculation of ORps. Odds ratios greater than 1.0 favored the experimental arm versus control (i.e., early chest irradiation). If statistical heterogeneity was demonstrated, sensitivity analyses were performed by previously described methods to evaluate possible sources of heterogeneity across the included studies. Pooling data from eight randomized controlled trials enrolling over 1,500 patients showed that early integration of chest radiotherapy with systemic chemotherapy increases overall survival by 34%-216%, depending on the end point of interest. Etoposide (E) plus cisplatin (P) in conjunction with chest irradiation appears to offer the greatest increase in survival versus delayed or split-course radiation therapy and non-EP-containing drug schedules. The available randomized trial data support early concurrent chest radiotherapy and systemic chemotherapy in the form of E and P in the management of limited-stage small cell lung cancer.

Time without symptoms and toxicity (TWIST) analysis of adjuvant radiation therapy for endometrial cancer

BACKGROUND AND PURPOSE

Postoperative radiotherapy in endometrial cancer reduces the risk of local relapse but is also associated with substantial acute and late reactions. The aim of our study was to evaluate time without tumor symptoms and toxicity (TWIST) in a consecutive series of 317 endometrial cancer patients administered postoperative irradiation.

PATIENTS AND METHODS

Both low-dose rate brachytherapy (BRT) and external beam irradiation (EBRT) were applied in 247 patients (78%), only BRT--in 49 (15%) and only EBRT--in 21 patients (7%). Median follow-up was 7.3 years (range, 4-21 years). TWIST analysis based on actuarial freedom from recurrent disease and from late radiotherapy effects was performed with the use of Kaplan-Meier method. The impact of patient- and treatment-related factors on TWIST was assessed with uni- and multivariate tests.

RESULTS

Five-year overall survival was 78%, and five-year disease free survival--75%. Recurrence occurred in 70 patients (22%), of whom in 11 (3.5%)--exclusively in the pelvis. Acute and late reactions of any grade occurred in 268 (85%) and 158 patients (51%), respectively. Late bowel effects of any grade were observed in 41% of patients. Severe late effects occurred in 35 patients (11%). Actuarial probability of two- and five-year survival free of disease and severe (grades 3 or 4) late effects (TWIST) was 84% and 71%, respectively (median TWIST, 16.2 years). When all-grade late effects were considered, two- and five-year TWIST probability was 50 and 30%, respectively, and median TWIST was only 2.0 years. When both acute and late reactions were taken into account, median TWIST was 22 months. In unifactorial test, higher age ( P = 0.013) FIGO stage ( P < 0.001) total radiotherapy dose ( P < 0.001) normalized total dose based on linear-quadratic model ( P = 0.001) EBRT fraction dose ( P < 0.001) and use of cesium BRT ( P = 0.042) were correlated with shorter TWIST. In multifactorial analysis, higher age ( P = 0.001) FIGO stage ( P = 0.001) and total radiotherapy dose ( P < 0.001) were independent factors correlated with shorter TWIST.

CONCLUSIONS

Endometrial cancer patients treated with postoperative irradiation have a long time interval without relapse and severe late toxicity. However, when any late normal tissue injury is considered, the median time without relapse and late toxicity is significantly shorter. The impact of mild late radiotherapy complications on the quality of life should be further investigated. TWIST calculation should be attempted in future prospective studies evaluating the role of postoperative radiotherapy.

Twenty-year follow-up study of long-term survival of limited-stage small-cell lung cancer and overview of prognostic and treatment factors

PURPOSE

To predict the long-term survival results of clinical trials earlier than using actuarial methods and to assess the factors predictive of long-term cure in patients with limited-stage small-cell lung cancer.

METHODS AND MATERIALS

Between 1981 and 1998, 1417 new cases of small-cell lung cancer were diagnosed in Saskatchewan, Canada, of which 244 were limited stage and treated with curative intent. They were followed to the end of February 2002. A parametric lognormal statistical model was retrospectively validated to determine whether long-term survival rates could be estimated several years earlier than is possible using the standard life-table actuarial method.

RESULTS

The survival time of the uncured group followed a lognormal distribution. Four 2-year periods of diagnosis were combined, and patients were followed as a cohort for an additional 2 years. The estimated 10-year cause-specific survival rate was 13% by the lognormal model. The Kaplan-Meier calculation for 10-year cause-specific survival rate was 15% +/- 3%. The data also showed that the absence of mediastinal lymphadenopathy and higher chest radiotherapy dose were significant prognostic factors on multivariate analysis (p < 0.05). Among the 163 patients given prophylactic cranial irradiation, a higher biologically effective dose to the brain did not improve survival or decrease the incidence of brain metastases.

CONCLUSION

The lognormal model has been validated for the estimation of survival in patients with limited-stage small-cell lung cancer. A higher biologically effective dose to the brain did not improve survival or decrease the incidence of brain metastases.