Prophylactic cranial irradiation in extensive small-cell lung cancer

Lung cancer: current diagnosis and treatment

BACKGROUND

Much progress has been made in the treatment of lung cancer in the last ten years (adjuvant chemotherapy, targeted therapy, individualized therapy). Nonetheless, lung cancer is still the leading cause of death due to cancer and thus remains a major medical, scientific, and social problem.

METHOD

This review is based on national and international recommendations and selected articles from the literature.

RESULTS

Cigarette smoking is the major pathogenic factor for lung cancer. Lung cancer can be divided into two major types that differ in their biological behavior, small cell lung cancer and non-small cell lung cancer. Whenever possible, the diagnosis should be confirmed by biopsy, the extent of disease should be documented in detail (international TNM classification/staging), and the patient's functional level should be assessed with a view toward treatment planning. Surgery for non-small cell lung cancer with curative intent is possible up to stage IIIA, while stage IIIB is the domain of radiotherapy. Surgery for small cell lung cancer with curative intent is possible for rare cases in early stages (T1N0 and T2N0, i.e., stage IA and IB). As long as small cell lung cancer is restricted to one side of the chest, simultaneous radiation therapy and chemotherapy are indicated. If a malignant pleural effusion or distant metastases are present, both lung cancers are treated palliatively with platinum-based chemotherapy.

Radiochemotherapy in the elderly with lung cancer

Lung cancer is the leading cause of cancer mortality with the median age of incidence being 69 years in males and 67 years in females. Radiochemotherapy (RT-CHT) is indicated in locally advanced non-small-cell lung cancer and limited-stage small-cell lung cancer; however, a significant under-representation of the elderly has been observed in patient recruitment in cancer treatment trials. In the last decades of the 20th Century, studies showed that elderly patients achieved the best quality-adjusted survival with radiotherapy alone, but recent trials have found that fit elderly patients benefit from concurrent RT-CHT, although with more short-term toxicity. Age alone should not exclude fit patients and deprive them of the standard treatment. Using tools, such as comprehensive geriatric assessment, a patient's tolerance to therapy can be assessed and monitoring can be performed. This review will focus on RT-CHT treatment in elderly patients with nonoperable stage III non-small-cell lung cancer and limited-stage small-cell lung cancer exclusively.

Twenty-seven years of phase III trials for patients with extensive disease small-cell lung cancer: disappointing results

Background

Few studies have formally assessed whether treatment outcomes have improved substantially over the years for patients with extensive disease small-cell lung cancer (ED-SCLC) enrolled in phase III trials. The objective of the current investigation was to determine the time trends in outcomes for the patients in those trials.

Methods and Findings

We searched for trials that were reported between January 1981 and August 2008. Phase III randomized controlled trials were eligible if they compared first-line, systemic chemotherapy for ED-SCLC. Data were evaluated by using a linear regression analysis. Results: In total, 52 trials were identified that had been initiated between 1980 and 2006; these studies involved 10,262 patients with 110 chemotherapy arms. The number of randomized patients and the proportion of patients with good performance status (PS) increased over time. Cisplatin-based regimens, especially cisplatin and etoposide (PE) regimen, have increasingly been studied, whereas cyclophosphamide, doxorubicin, and vincristine–based regimens have been less investigated. Multiple regression analysis showed no significant improvement in survival over the years. Additionally, the use of a PE regimen did not affect survival, whereas the proportion of patients with good PS and the trial design of assigning prophylactic cranial irradiation were significantly associated with favorable outcome.

Conclusions and Significance

The survival of patients with ED-SCLC enrolled in phase III trials did not improve significantly over the years, suggesting the need for further development of novel targets, newer agents, and comprehensive patient care.

CNS complications of radiotherapy and chemotherapy

Treatment-induced CNS toxicity remains a major cause of morbidity in patients with cancer. Advances in the design of safe radiation procedures have been counterbalanced by widespread use of combined radiotherapy and chemotherapy, development of radiosurgery, and the increasing number of long-term survivors. Although classic radionecrosis and chemonecrosis have become less common, subtle changes such as progressive cognitive dysfunction are increasingly reported after radiotherapy (radiation-induced leukoencephalopathy) or chemotherapy (given alone or in combination). We review the most important and controversial complications of radiotherapy, chemotherapy, and combined treatments in the CNS, and discuss new diagnostic tools, practical management, prevention, and pathophysiological data that will affect future management of patients with cancer.

Brain metastases admissions in Sweden between 1987 and 2006

Background:

Brain metastases (BM) constitute the most common intracranial tumours and are associated with considerable morbidity and mortality. Population-based studies of the epidemiology and time trends of BM are scarce.

Methods:

A population-based cohort of patients admitted to hospital with BM in Sweden between 1987 and 2006 (n=15 517) was identified and linked to nationwide registers of cancer incidence and death. Primary cancer types were assessed and time to hospitalisation and death was computed.

Results:

The annual age-adjusted incidence rate of hospitalisation for BM doubled from 7 to 14 patients per 100 000 between 1987 and 2006. The most common primary tumours among women were lung (33%), breast (33%) and colorectal cancer (7%), and among men lung cancer (44%), malignant melanoma (12%) and colorectal cancer (9%). The increase was most evident for BM patients with lung cancer (both sexes) and breast cancer (women). Survival was short, with a median of 2.7 months. It varied little by cancer type and did not improve over calendar time.

Conclusion:

The number of patients admitted with BM has increased rapidly in Sweden. In spite of recent improvements in the prognosis of common primary cancer types, any parallel improvement among patients with advanced cancer and BM is not indicated.

The role of intra-cerebrospinal fluid treatment and prophylaxis in patients with solid tumors

Metastasis to the central nervous system (CNS), including neoplastic meningitis (NM), is a devastating complication of systemic cancer. With the improved survival of cancer patients, the incidence of CNS metastasis is rising, especially among those with breast or lung carcinoma. New therapies that effectively treat these primary tumors outside of the CNS have underscored the significance of CNS metastases; they have become a significant clinical issue and a therapeutic challenge. This review discusses clinical situations in which treatment or chemoprophylaxis of CNS metastases and NM from breast or lung cancer may play an important role. Potential clinical trials to assess these assumptions also will be proposed.

Uptake of ANG1005, a novel paclitaxel derivative, through the blood-brain barrier into brain and experimental brain metastases of breast cancer

PURPOSE

We evaluated the uptake of angiopep-2 paclitaxel conjugate, ANG1005, into brain and brain metastases of breast cancer in rodents. Most anticancer drugs show poor delivery to brain tumors due to limited transport across the blood-brain barrier (BBB). To overcome this, a 19-amino acid peptide (angiopep-2) was developed that binds to low density lipoprotein receptor-related protein (LRP) receptors at the BBB and has the potential to deliver drugs to brain by receptor-mediated transport.

METHODS

The transfer coefficient (K(in)) for brain influx was measured by in situ rat brain perfusion. Drug distribution was determined at 30 min after i.v. injection in mice bearing intracerebral MDA-MB-231BR metastases of breast cancer.

RESULTS

The BBB K(in) for (125)I-ANG1005 uptake (7.3 +/- 0.2 x 10(-3) mL/s/g) exceeded that for (3)H-paclitaxel (8.5 +/- 0.5 x 10(-5)) by 86-fold. Over 70% of (125)I-ANG1005 tracer stayed in brain after capillary depletion or vascular washout. Brain (125)I-ANG1005 uptake was reduced by unlabeled angiopep-2 vector and by LRP ligands, consistent with receptor transport. In vivo uptake of (125)I-ANG1005 into vascularly corrected brain and brain metastases exceeded that of (14)C-paclitaxel by 4-54-fold.

CONCLUSIONS

The results demonstrate that ANG1005 shows significantly improved delivery to brain and brain metastases of breast cancer compared to free paclitaxel.

Chemoradiation for small cell esophageal carcinoma: report of 11 cases from multi-institution experience

Small cell esophageal carcinoma(SCEC) is a rare disease with aggressive behavior and poor prognosis. Because of the rarity of this disease, standard therapy has not yet been established. The objective of this retrospective study was to report the outcomes of SCEC treated with chemotherapy and radiotherapy from a retrospective study of 11 patients. We enrolled 11 SCEC patients who were treated with radiation therapy (more than 50 Gy) and chemotherapy between May 1996 and October 2007. Patients' age ranged from 44 to 77 years (mean: 69 years). In all patients, pathological examination of the specimen obtained by biopsy revealed small cell carcinoma. All patients were treated with chemotherapy and radiation therapy. The mean follow-up time was 14.7 months, and the median overall survival time of all patients was 13.2 months (range: 4.2-43.6 months). The 1-year and 3-year overall survival rates were 63% and 24%, respectively, while the 1-year and 3-year progression-free survival rates were 45% and 14%, respectively. Five of seven patients with complete response (CR) developed recurrent disease. Recurrence sites were distant metastases in four patients and lymph node outside the radiation field in one patient. Chemoradiation should be considered as one of the important treatment options for the loco-regional control in the patients with SCEC.

Thirty years' experience with Gamma Knife surgery for metastases to the brain

Object

The aim of this study was to analyze factors influencing survival time and patterns of distant recurrences after Gamma Knife surgery (GKS) for metastases to the brain.

Methods

Information was available for 1855 of 1921 patients who underwent GKS for single or multiple cerebral metastases at 4 different institutions during different time periods between 1975 and 2007. The total number of Gamma Knife treatments administered was 2448, an average of 1.32 treatments per patient. The median survival time was analyzed, related to patient and treatment parameters, and compared with published data following conventional fractionated whole-brain irradiation.

Results

Twenty-five patients survived for longer than 10 years after GKS, and 23 are still alive. Age and primary tumor control were strongly related to survival time. Patients with single metastases had a longer survival than those with multiple metastases, but there was no difference in survival between patients with single and multiple metastases who had controlled primary disease. There were no significant differences in median survival time between patients with 2, 3–4, 5–8, or > 8 metastases. The 5-year survival rate was 6% for the whole patient population, and 9% for patients with controlled primary disease. New hematogenous spread was a more significant problem than micrometastases in patients with longer survival.

Conclusions

Patient age and primary tumor control are more important factors in predicting median survival time than number of metastases to the brain. Long-term survivors are more common than previously assumed.

Prognostic factors differ by tumor stage for small cell lung cancer: a pooled analysis of North Central Cancer Treatment Group trials

BACKGROUND

An analysis of 14 small cell lung cancer (SCLC) trials was performed to improve the current understanding of potential prognostic factors for overall survival (OS) and progression-free survival (PFS) in groups of patients with limited-stage disease SCLC (LD-SCLC) and extensive-stage disease SCLC (ED-SCLC) separately.

METHODS

Data on 688 patients with LD-SCLC and 910 patients with ED-SCLC were included. Clinical and laboratory factors were tested for their prognostic significance using Cox regression models that were stratified by protocol. Recursive partitioning and amalgamation (RPA) analyses were used to identify prognostic subgroups.

RESULTS

Poorer performance status (PS) led to worse OS and PFS in the ED-SCLC group but not in the LD-SCLC group. The prognostic impact of PS was strong for men but weak for women in the ED-SCLC group (interaction P value <.012 for OS and PFS). Other negative prognostic factors included increased age and men for the LD-SCLC group and increased age, men, increased number of metastatic sites at baseline, and increased creatinine levels for the ED-SCLC group. In patients with the ED-SCLC, RPA analyses identified 5 subgroups with different prognosis based on baseline PS, creatinine levels, sex, and the number of metastatic sites.

CONCLUSIONS

The current pooled analysis identified baseline creatinine levels and the number of metastatic sites as important prognostic factors in patients with ED-SCLC in addition to the well established factors of sex, age, and PS. There was a significant interaction between sex and PS within the ED-SCLC group, suggesting that PS is highly prognostic in men but has no significant impact in women. Within the LD-SCLC group, only age and sex were identified as important prognostic factors. RPA analyses confirmed many of these findings.

Prognostic factors for limited-stage small cell lung cancer: a study of 284 patients

Combined modality therapy is the standard care for limited stage-small cell lung cancer (LS-SCLC) and has led to a significant improvement in patients' survival. This study sought to investigate and define the importance of prognostic effects of known and controversial factors especially the impact of smoking status and treatment strategies. A total of 284 patients with LS-SCLC were diagnosed and prospectively followed from 1997 to 2008 at Mayo Clinic; their characteristics and survival outcome were assessed on the basis of age, gender, smoking history, performance status (PS), tumor recurrence or progression, and treatment using Cox proportional hazards models. Our main results are as follows: (1) Although neither smoking status (former or current smokers) nor intensity (pack-years smoked) at the time of SCLC diagnosis were significant survival predictors, compared to continued smokers (who never quit smoking), patients who quit at or after diagnosis cut the risk of death by 45% (HR=0.55, 95% CI 0.38-0.79); patients who quit before lung cancer diagnosis also experienced survival benefit (HR=0.72, 95% CI 0.52-1.00). (2) Thoracic radiotherapy and platinum-based chemotherapy could significantly improve survival but the timing (within or after one month of diagnosis) of starting chemotherapy or radiation therapy did not. (3) After adjusting for other known factors, a lower PS did not predict poorer survival, suggesting that PS should not be the only factor for making treatment decisions. In conclusion, this study demonstrated the negative impact of continued cigarette smoking on survival; therefore, clinicians and all care providers should strongly encourage smoking cessation at diagnosis of LS-SCLC.

A phase II study of carboplatin, etoposide, and exisulind in patients with extensive small cell lung cancer: CALGB 30104

PURPOSE

To assess the efficacy and toxicity of carboplatin, etoposide, and exisulind as initial therapy for extensive stage small cell lung cancer.

PATIENTS AND METHODS

The Cancer and Leukemia Group B conducted a phase II study of carboplatin (area under the curve 6) day 1 and etoposide 80 mg/m(2) days 1-3 administered intravenously every 21 days with exisulind 250 mg orally twice daily in 44 evaluable patients with previously untreated extensive stage small cell lung cancer. The hypothesis was the addition of a novel cytostatic agent to standard therapy may increase survival time. The primary end point of the study was to evaluate overall survival. The secondary end points were to characterize response rates and toxicity.

RESULTS

The majority of the patients were male (64%), Caucasian (95%), and had performance status 0 or 1 (77%). The median age was 61 (range 44-82) years. The percentage of patients alive at 1 year was 36.4% (95% [confidence interval] CI: 24.6-53.8%). The median overall survival was 10.6 months (95% CI: 9.1-14.7). The best overall response rate was 77% (95% CI: 62-89%) with 16% of the patients achieving complete response. The most frequent grade 3 or grade 4 hematological toxicities were neutropenia (64%), thrombocytopenia (36%), and febrile neutropenia (16%). The most common grade 3 or grade 4 nonhematological toxicities were gastrointestinal (30%) and electrolyte changes (23%).

CONCLUSIONS

The addition of exisulind to a standard regimen of carboplatin and etoposide did not improve outcomes compared with historic controls treated with chemotherapy alone. Further evaluation of this regimen in small cell lung cancer is not warranted.

Standard-dose versus higher-dose prophylactic cranial irradiation (PCI) in patients with limited-stage small-cell lung cancer in complete remission after chemotherapy and thoracic radiotherapy (PCI 99-01, EORTC 22003-08004, RTOG 0212, and IFCT 99-01): a randomised clinical trial

BACKGROUND

The optimum dose of prophylactic cranial irradiation (PCI) for limited-stage small-cell lung cancer (SCLC) is unknown. A meta-analysis suggested that the incidence of brain metastases might be reduced with higher PCI doses. This randomised clinical trial compared the effect of standard versus higher PCI doses on the incidence of brain metastases.

METHODS

Between September, 1999, and December, 2005, 720 patients with limited-stage SCLC in complete remission after chemotherapy and thoracic radiotherapy from 157 centres in 22 countries were randomly assigned to a standard (n=360, 25 Gy in 10 daily fractions of 2.5 Gy) or higher PCI total dose (n=360, 36 Gy) delivered using either conventional (18 daily fractions of 2 Gy) or accelerated hyperfractionated (24 fractions in 16 days with two daily sessions of 1.5 Gy separated by a minimum interval of 6 h) radiotherapy. All of the treatment schedules excluded weekends. Randomisation was stratified according to medical centre, age (</=60 and >60 years), and interval between the start of induction treatment and the date of randomisation (</=90, 91-180, and >180 days). Eligible patients were randomised blindly by the data centre of the Institut Gustave Roussy (PCI99-01 and IFCT) using minimisation, and by the data centres of EORTC (EORTC ROG and LG) and RTOG (for CALGB, ECOG, RTOG, and SWOG), both using block stratification. The primary endpoint was the incidence of brain metastases at 2 years. Analysis was by intention-to-treat. This study is registered with ClinicalTrials.gov number NCT00005062.

FINDINGS

Five patients in the standard-dose group and four in the higher-dose group did not receive PCI; nonetheless, all randomised patients were included in the effectiveness anlysis. After a median follow-up of 39 months (range 0-89 months), 145 patients had brain metastases; 82 in the standard-dose group and 63 in the higher-dose group. There was no significant difference in the 2-year incidence of brain metastases between the standard PCI dose group and the higher-dose group, at 29% (95% CI 24-35) and 23% (18-29), respectively (hazard ratio [HR] 0.80 [95% CI 0.57-1.11], p=0.18). 226 patients in the standard-dose group and 252 in the higher-dose group died; 2-year overall survival was 42% (95% CI 37-48) in the standard-dose group and 37% (32-42) in the higher-dose group (HR 1.20 [1.00-1.44]; p=0.05). The lower overall survival in the higher-dose group is probably due to increased cancer-related mortality: 189 patients in the standard group versus 218 in the higher-dose group died of progressive disease. Five serious adverse events occurred in the standard-dose group versus zero in the higher-dose group. The most common acute toxic events were fatigue (106 [30%] patients in the standard-dose group vs 121 [34%] in the higher-dose group), headache (85 [24%] vs 99 [28%]), and nausea or vomiting (80 [23%] vs 101 [28%]).

INTERPRETATION

No significant reduction in the total incidence of brain metastases was observed after higher-dose PCI, but there was a significant increase in mortality. PCI at 25 Gy should remain the standard of care in limited-stage SCLC.

FUNDING

Institut Gustave-Roussy, Association pour la Recherche sur le Cancer (2001), Programme Hospitalier de Recherche Clinique (2007). The European Organisation for Research and Treatment of Cancer (EORTC) contribution to this trial was supported by grants 5U10 CA11488-30 through 5U10 CA011488-38 from the US National Cancer Institute.

Evaluation of the use of prophylactic cranial irradiation in small cell lung cancer

BACKGROUND

Prophylactic cranial irradiation has been used in patients with small cell lung cancer to reduce the incidence of brain metastasis after primary therapy. The purpose of this study was to evaluate the effects of prophylactic cranial irradiation (PCI) on overall survival and cause-specific survival.

METHODS

A total of 7995 patients with limited stage small cell lung cancer diagnosed between 1988 and 1997 were retrospectively identified from centers participating in the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) Program. Of them, 670 were identified as having received PCI as a component of their first course of therapy. Overall survival and cause-specific survival were estimated by the Kaplan-Meier method, comparing patients treated with or without prophylactic whole-brain radiotherapy. The Cox proportional hazards model was used in the multivariate analysis to evaluate potential prognostic factors.

RESULTS

The median follow-up time was 13 months (range, 1 month to 180 months). Overall survival at 2 years, 5 years, and 10 years was 23%, 11%, and 6%, respectively, in patients who did not receive PCI. In patients who received PCI, the 2-year, 5-year, and 10-year overall survival rates were 42%, 19%, and 9%, respectively (P =or <.001). The cause-specific survival rate at 2 years, 5 years, and 10 years was 28%, 15%, 11%, respectively, in patients who did not receive PCI and 45%, 24%, 17%, respectively, in patients who did receive PCI (P =or <.001). On multivariate analysis of cause-specific and overall survival, age at diagnosis, sex, grade, extent of primary disease, size of disease, extent of lymph node involvement, and PCI were found to be significant (P = or<.001). The hazards ratios for disease-specific and all cause mortality were 1.13 and 1.11, respectively, for those not receiving PCI.

CONCLUSIONS

Significantly improved overall and cause-specific survival was observed in patients treated with prophylactic cranial irradiation on unadjusted and adjusted analyses. This study concurs with the previously published European experience. Prophylactic cranial irradiation should be considered for patients with limited stage small cell lung cancer.

Prognostic factors for survival in extensive stage small cell lung cancer (ED-SCLC): the importance of smoking history, socioeconomic and marital statuses, and ethnicity

BACKGROUND

: We investigated whether independent prognostic factors for overall survival (OS) in non-small cell lung cancer such as ethnicity, smoking history, socioeconomic, and marital statuses are also applicable to extensive stage small cell lung cancer (ED-SCLC).

METHODS

: SCLC patients diagnosed from 1991 to 2005 from 3 Southern California counties were identified. Prognostic factors for ED-SCLC patients were evaluated by univariate and multivariate analysis.

RESULTS

: Of the 4782 SCLC patients analyzed, only 2.5% of the patients were never-smokers and 71.7% of patients presented with ED-SCLC. By multivariate analysis, a positive smoking status was a statistically significant poor prognostic factor for OS in ED-SCLC patients (versus never-smoker; hazard ratio [HR] = 1.310; p = 0.0125), in addition low socioeconomic status (SES) (from the lowest to the highest SES score; ptrend = 0.0128) and being unmarried (versus married; HR = 1.179; p < 0.0001). Asian ethnicity was a favorable prognostic factor in ED-SCLC (versus Caucasian; HR = 0.785; p = 0.0076). Female gender was another independent favorable prognostic factor (versus male; HR = 0.823; p < 0.0001).

CONCLUSIONS

: A positive history of smoking, low SES, and being unmarried are independent unfavorable prognostic factors for OS in ED-SCLC while Asian ethnicity and female gender are independent favorable prognostic factors for OS in ED-SCLC by multivariate analysis.

Association between incremental gains in the objective response rate and survival improvement in phase III trials of first-line chemotherapy for extensive disease small-cell lung cancer

BACKGROUND

The duration of, resources required for and cost of clinical trials could be reduced if a surrogate end point was to be used in place of survival. We assessed the extent to which the objective response rate (ORR) is predictive of mortality, how much difference in the ORR is needed to predict an obvious survival difference and what factors could affect the association between the two parameters during the first-line treatment of extensive disease (ED)-small-cell lung cancer (SCLC).

METHODS

We used the ORRs and median survival times (MSTs) from 48 phase III trials of first-line chemotherapy involving 8779 randomised patients with ED-SCLC in a linear regression analysis. The MST difference was calculated as the difference in MST between the investigational and reference arms; the ORR difference was similarly defined.

RESULTS

ORR difference between the treatment arms was modestly associated with the MST difference in the overall trials (R(2) = 0.3314). In contrast, the relationship was stronger among only trials in which prophylactic cranial irradiation was given to those having an objective response to the initial chemotherapy (R(2) = 0.6279). In this trial setting, large differences in ORR were needed to predict a survival advantage (1.2-day survival advantage per 2% increase in ORR).

CONCLUSIONS

In the first-line treatment of ED-SCLC, a favourable relationship was detected between the two parameters in the selected trial setting. Large ORR differences were needed to predict a survival benefit, clearly suggesting the need for new chemotherapeutic agents.

The expression of three genes in primary non-small cell lung cancer is associated with metastatic spread to the brain

PURPOSE

Brain metastases affect 25% of patients with non-small cell lung cancer (NSCLC). We hypothesized that the expression of genes in primary NSCLC tumors could predict brain metastasis and be used for identification of high-risk patients, who may benefit from prophylactic therapy.

EXPERIMENTAL DESIGN

The expression of 12 genes was measured by real-time quantitative reverse transcriptase PCR in 142 frozen NSCLC tissue samples. Univariate and multivariate Cox regression analysis was used to analyze the correlation between gene expression and the occurrence of brain metastasis. Immunohistochemistry on independent samples was used to verify the findings.

RESULTS

A score based on the expression levels of three genes, CDH2 (N-cadherin), KIFC1, and FALZ, was highly predictive of brain metastasis in early and advanced lung cancer. The probability of remaining brain metastasis-free at 2 years after diagnosis was 90.0+/-9.5% for patients with stage I/stage II tumors and low score compared with 62.7+/-12% for patients with high score (P<0.01). In patients with more advanced lung cancer, the brain metastasis-free survival at 24 months was 89% for patients with low score compared with only 37% in patients with high score (P<0.02). These results were confirmed by immunohistochemical detection of N-cadherin in independent cohort of primary NSCLC.

CONCLUSIONS

The expression levels of three genes in primary NSCLC tumors may be used to identify patients at high risk for brain metastasis who may benefit from prophylactic therapy to the central nervous system.

Should irinotecan or etoposide be used in combination with carboplatin for small cell lung cancer?

Little progress has been made in the treatment of small cell lung cancer over the past two decades. Superiority of combined irinotecan-cisplatin over standard etoposide-cisplatin in a Japanese phase III trial was not confirmed in two subsequent US studies. In this Practice Point we discuss a randomized, phase III trial by Hermes and colleagues, which included 220 patients with extensive-disease small cell lung cancer and showed superiority of carboplatin-irinotecan versus carboplatin-oral etoposide. In this trial, 47% of patients had a performance status > or = 3 and 35% were older than 70 years, which represents a typical clinical practice population of patients; however, oral administration of etoposide and an arbitrary dose reduction in elderly and unfit patients represent limitations of the study. A European trial of irinotecan-carboplatin versus intravenous etoposide-carboplatin has completed accrual and results will be analyzed in 2009. Although the results of the study by Hermes et al. are of interest, substitution of etoposide by irinotecan can not be recommended.

Clinical and therapeutic aspects of extrapulmonary small cell carcinoma

Extrapulmonary small cell carcinoma (EPSCC) is usually treated similarly to small cell lung cancer. Differences in aetiology, clinical course, frequency of brain metastases, and survival, however, warrant a differential therapeutic approach. In this review, we focus on the treatment of the most predominant sites of origin of EPSCC; the gastrointestinal tract, the genitourinary tract, the head and neck region, and small cell carcinoma of unknown primary. Furthermore we review the available data concerning the controversial issue of prophylactic cranial irradiation (PCI) after optimal treatment of EPSCC. We found in the literature a significant lower incidence of brain metastases in EPSCC as compared to pulmonary small cell carcinoma when PCI is omitted and therefore we do not recommend PCI. An exception is EPSCC originating from the head and neck region which is associated with a higher incidence of brain metastasis, justifying addition of PCI.

Prophylactic cranial irradiation in extensive disease small-cell lung cancer: short-term health-related quality of life and patient reported symptoms: results of an international Phase III randomized controlled trial by the EORTC Radiation Oncology and Lung Cancer Groups

PURPOSE

Prophylactic cranial irradiation (PCI) in patients with extensive-disease small-cell lung cancer (ED-SCLC) leads to significantly fewer symptomatic brain metastases and improved survival. Detailed effects of PCI on health-related quality of life (HRQOL) are reported here.

PATIENTS AND METHODS

Patients (age, 18 to 75 years; WHO < or = 2) with ED-SCLC, and any response to chemotherapy, were randomly assigned to either observation or PCI. Health-related quality of life (HRQOL) and patient-reported symptoms were secondary end points. The European Organisation for the Research and Treatment of Cancer core HRQOL tool (Quality of Life Questionnaire C30) and brain module (Quality of Life Questionnaire Brain Cancer Module) were used to collect self-reported patient data. Six HRQOL scales were selected as primary HRQOL end points: global health status; hair loss; fatigue; and role, cognitive and emotional functioning. Assessments were performed at random assignment, 6 weeks, 3 months, and then 3-monthly up to 1 year and 6-monthly thereafter.

RESULTS

Compliance with the HRQOL assessment was 93.7% at baseline and dropped to 60% at 6 weeks. Short-term results up to 3 months showed that there was a negative impact of PCI on selected HRQOL scales. The largest mean difference between the two arms was observed for fatigue and hair loss. The impact of PCI on global health status as well as on functioning scores was more limited. For global health status, the observed mean difference was eight points on a scale 0 to 100 at 6 weeks (P = .018) and 3 months (P = .055).

CONCLUSION

PCI should be offered to all responding ED SCLC patients. Patients should be informed of the potential adverse effects from PCI. Clinicians should be alert to these; monitor their patients; and offer appropriate support, clinical, and psychosocial care.

Topotecan in the treatment of relapsed small cell lung cancer

Small cell lung cancer (SCLC) represents about 15% to 20% of all lung cancers. Chemotherapy is the cornerstone of the treatment, cisplatin–etoposide combination being the most used combination as first-line therapy. Despite high initial chemosensitivity, most SCLC patients will experience relapse sooner or later. Unfortunately, second-line chemotherapy does not result in a high response rate like first-line therapy, most patients having developed wide chemoresistance. This chemoresistance is far more important in refractory patients, ie, those who never responded to first-line therapy or who relapsed within 3 months after the end of chemotherapy, than in sensitive patients, ie, those who relapse more than 3 months after the end of chemotherapy. Topotecan, a topoisomerase I inhibitor, is the most studied drug in this second-line setting and has proved its efficacy as a single agent and in combination. A phase III trial comparing oral topotecan to best supportive care (BSC) in relapsed SCLC demonstrated a significant survival benefit as well as a better quality of life. Although the usual schedule is 1.5 mg/m², days 1–5 intravenously, it is not convenient for patients with relapsed SCLC, especially those who are refractory because of their short survival expectation. Oral topotecan is of similar efficacy and much more convenient with limited stay in a treatment unit and has a comparable toxicity profile for these patients with short expected survival. Combination of topotecan with platinum salts or taxanes does not seem to improve further the outcome of the patients and thus single-agent therapy with topotecan is the standard treatment for relapsed SCLC.

SCLC extensive disease--treatment guidance by extent or/and biology of response?

In extensive disease of small cell lung cancer a doubling of the one-year-survival rate was reported in August 2007 by prophylactic cranial irradiation applied to patients who experienced any response to initial chemotherapy. We discuss the treatment concept of extensive disease in the face of the latest results and older studies with additional thoracic irradiation in this subgroup. A randomized trial with prophylactic cranial irradiation published in 1999 demonstrated an improvement of 5-year-overall-survival for complete responders (at least at distant levels) receiving additional thoracic radiochemotherapy compared to chemotherapy alone (9.1% vs. 3.7%). But, these results were almost neglected and thoracic radiotherapy was not further investigated for good responders of extensive disease. However, in the light of current advances by prophylactic cranial irradiation these findings are noteworthy on all accounts. Considering both, a possible interpretation of these data could be a survival benefit of local control by simultaneous thoracic radiochemotherapy in the case of improved distant control due to chemotherapy and prophylactic cranial irradiation. Furthermore the question arises whether the tumor biology indicated by the response to chemotherapy should be integrated in the present classification.

Irinotecan Plus Carboplatin Versus Oral Etoposide Plus Carboplatin in Extensive Small-Cell Lung Cancer: A Randomized Phase III Trial

Purpose

A Japanese randomized trial showed superior survival for patients with extensive-disease (ED) small-cell lung cancer (SCLC) receiving irinotecan plus cisplatin compared with etoposide plus cisplatin. The present trial evaluated the efficacy of irinotecan plus carboplatin (IC) compared with oral etoposide plus carboplatin (EC).

Patients and Methods

Patients with ED SCLC were randomly assigned to receive either IC, which consisted of carboplatin (area under the curve = 4; Chatelut formula) and irinotecan (175 mg/m2) intravenously both on day 1, or EC, which consisted of carboplatin as in IC and etoposide (120 mg/m2/d) orally on days 1 through 5. Courses were repeated every 3 weeks with four cycles planned. Doses were reduced by one third in patients with a WHO performance status (PS) of 3 to 4 and/or age older than 70 years. Primary end point was overall survival (OS). Secondary end points were quality of life (QOL) and complete response (CR) rate.

Results

Of 220 randomly assigned patients, 209 were eligible for analysis (IC, n = 105; EC, n = 104). Thirty-five percent were older than 70 years, and 47% had a PS of 2 to 4. The groups were well balanced with respect to prognostic factors. OS was inferior in the EC group (hazard ratio = 1.41; 95% CI, 1.06 to 1.87; P = .02). Median survival time was 8.5 months for IC compared with 7.1 months for EC. One-year survival rate was 34% for IC and 24% for EC. CR was seen in 18 IC patients compared with seven EC patients (P = .02). There were no statistically significant differences in hematologic grade 3 or 4 toxicity. Grade 3 or 4 diarrhea was more common in the IC group. QOL differences were small, with a trend toward prolonged palliation with the IC regimen.

Conclusion

IC prolongs survival in ED SCLC with slightly better scores for QOL.

Effect of lapatinib on the outgrowth of metastatic breast cancer cells to the brain

BACKGROUND

The brain is increasingly being recognized as a sanctuary site for metastatic tumor cells in women with HER2-overexpressing breast cancer who receive trastuzumab therapy. There are no approved or widely accepted treatments for brain metastases other than steroids, cranial radiotherapy, and surgical resection. We examined the efficacy of lapatinib, an inhibitor of the epidermal growth factor receptor (EGFR) and HER2 kinases, for preventing the outgrowth of breast cancer cells in the brain in a mouse xenograft model of brain metastasis.

METHODS

EGFR-overexpressing MDA-MB-231-BR (231-BR) brain-seeking breast cancer cells were transfected with an expression vector that contained or lacked the HER2 cDNA and used to examine the effect of lapatinib on the activation (ie, phosphorylation) of cell signaling proteins by immunoblotting, on cell growth by the tetrazolium salt 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay, and on cell migration using a Boyden chamber assay. The outgrowth of large (ie, >50 microm(2)) and micrometastases was counted in brain sections from nude mice that had been injected into the left cardiac ventricle with 231-BR cells and, beginning 5 days later, treated by oral gavage with lapatinib or vehicle (n = 22-26 mice per treatment group). All statistical tests were two-sided.

RESULTS

In vitro, lapatinib inhibited the phosphorylation of EGFR, HER2, and downstream signaling proteins; cell proliferation; and migration in 231-BR cells (both with and without HER2). Among mice injected with 231-BR-vector cells, those treated with 100 mg lapatinib/kg body weight had 54% fewer large metastases 24 days after starting treatment than those treated with vehicle (mean number of large metastases per brain section: 1.56 vs 3.36, difference = 1.80, 95% confidence interval [CI] = 0.92 to 2.68, P < .001), whereas treatment with 30 mg lapatinib/kg body weight had no effect. Among mice injected with 231-BR-HER2 cells, those treated with either dose of lapatinib had 50%-53% fewer large metastases than those treated with vehicle (mean number of large metastases per brain section, 30 mg/kg vs vehicle: 3.21 vs 6.83, difference = 3.62, 95% CI = 2.30 to 4.94, P < .001; 100 mg/kg vs vehicle: 3.44 vs 6.83, difference = 3.39, 95% CI = 2.08 to 4.70, P < .001). Immunohistochemical analysis revealed reduced phosphorylation of HER2 in 231-BR-HER2 cell-derived brain metastases from mice treated with the higher dose of lapatinib compared with 231-BR-HER2 cell-derived brain metastases from vehicle-treated mice (P < .001).

CONCLUSIONS

Lapatinib is the first HER2-directed drug to be validated in a preclinical model for activity against brain metastases of breast cancer.

Brain metastases in N2-positive non-small-cell lung cancer: implications for prophylactic cranial irradiation

Patients with non-small-cell lung cancer with positive lymph nodes (stage IIIA and IIIB) have an increased risk for brain metastases. Those with nonsquamous histology are at higher risk. Despite this fact, the use of prophylactic cranial irradiation (PCI) has not shown an improvement in survival in these patients and is still considered to be investigational. The Radiation Therapy Oncology Group attempted to prospectively address this in a randomized trial that recently closed because of poor accrual. We present 2 cases and review the literature and provide an argument for the consideration of PCI in select patients.

The development and investigation of a prototype three-dimensional compensator for whole brain radiation therapy

Whole brain radiation therapy (WBRT) is the standard treatment for patients with brain metastases, and is often used in conjunction with stereotactic radiotherapy for patients with a limited number of brain metastases, as well as prophylactic cranial irradiation. The use of open fields (conventionally used for WBRT) leads to higher doses to the brain periphery if dose is prescribed to the brain center at the largest lateral radius. These dose variations potentially compromise treatment efficacy and translate to increased side effects. The goal of this research was to design and construct a 3D 'brain wedge' to compensate dose heterogeneities in WBRT. Radiation transport theory was invoked to calculate the desired shape of a wedge to achieve a uniform dose distribution at the sagittal plane for an ellipsoid irradiated medium. The calculations yielded a smooth 3D wedge design to account for the missing tissue at the peripheral areas of the brain. A wedge was machined based on the calculation results. Three ellipsoid phantoms, spanning the mean and +/- two standard deviations from the mean cranial dimensions were constructed, representing 95% of the adult population. Film was placed at the sagittal plane for each of the three phantoms and irradiated with 6 MV photons, with the wedge in place. Sagittal plane isodose plots for the three phantoms demonstrated the feasibility of this wedge to create a homogeneous distribution with similar results observed for the three phantom sizes, indicating that a single wedge may be sufficient to cover 95% of the adult population. The sagittal dose is a reasonable estimate of the off-axis dose for whole brain radiation therapy. Comparing the dose with and without the wedge the average minimum dose was higher (90% versus 86%), the maximum dose was lower (107% versus 113%) and the dose variation was lower (one standard deviation 2.7% versus 4.6%). In summary, a simple and effective 3D wedge for whole brain radiotherapy has been developed. The wedge gives a more uniform dose distribution than commonly used techniques. Further development and shape optimization may be necessary prior to clinical implementation.

Small cell lung cancer

Small cell lung cancer accounts for approximately 15% of bronchogenic carcinomas. It is the cancer most commonly associated with various paraneoplastic syndromes, including the syndrome of inappropriate antidiuretic hormone secretion, paraneoplastic cerebellar degeneration, and Lambert-Eaton myasthenic syndrome. Because of the high propensity of small cell lung cancer to metastasize early, surgery has a limited role as primary therapy. Although the disease is highly sensitive to chemotherapy and radiation, cure is difficult to achieve. The combination of platinum and etoposide is the accepted standard chemotherapeutic regimen. It is also the accepted standard therapy in combination with thoracic radiotherapy (TRT) for limited-stage disease. Adding TRT increases absolute survival by approximately 5% over chemotherapy alone. Thoracic radiotherapy administered concurrently with chemotherapy is more efficacious than sequential therapy. Furthermore, the survival benefit is greater if TRT is given early rather than late in the course of chemotherapy. Regardless of disease stage, no relevant survival benefit results from increased chemotherapy dose intensity or dose density, altered mode of administration (eg, alternating or sequential administration) of various chemotherapeutic agents, or maintenance chemotherapy. Prophylactic cranial radiation prevents central nervous system recurrence and can improve survival. In Japan and some other Asian countries, the combination of irinotecan and cisplatin is the standard chemotherapeutic regimen. Clinical trials using thalidomide, gefitinib, imatinib, temsirolimus, and farnesyltransferase inhibitors have not shown clinical benefit. Other novel agents such as bevacizumab have shown promising early results and are being evaluated in larger trials.