Early versus late prophylactic cranial irradiation in patients with extensive small cell lung cancer.

OBJECTIVE: Previous studies demonstrated that prophylactic cranial irradiation (PCI) significantly reduced the incidence of brain metastases in patients with extensive disease small cell lung cancer (ED-SCLC). However, the appropriate timing for PCI in treating ED-SCLC is still unclear. This study aimed to compare the effect and safety of early versus late PCI. METHODS: Between November 2011 and July 2016, 103 patients with ED-SCLC were reviewed, receiving appropriate imaging tests to exclude brain metastases prior to cranial irradiation. Of these 103 patients, early PCI was performed in 47 patients and the other 56 patients received late PCI. The primary endpoint was the incidence of brain metastases. The progression-free survival (PFS), overall survival (OS), and adverse events (AEs) were also assessed. RESULTS: Early PCI significantly lowered the risk of brain metastases, as compared to late PCI (p = 0.024). Additionally, multivariate analyses demonstrated that early PCI was a favorable independent predictor of the incidence of brain metastases. The PFS and OS of patients in the early and late PCI groups were comparable (PFS: 8.4 months vs. 7.5 months, p = 0.234; OS: 16.1 months vs. 15.2 months, p = 0.753). The AEs were generally acceptable in both groups. CONCLUSION: To reduce the incidence of brain metastases, early PCI is more effective than late PCI for ED-SCLC patients.

Role of Adjuvant Therapy in a Population-Based Cohort of Patients With Early-Stage Small-Cell Lung Cancer.

PURPOSE: Data on optimal adjuvant therapy after complete resection of small-cell lung cancer (SCLC) are limited, and in particular, there have been no studies evaluating the role of adjuvant chemotherapy, with or without prophylactic cranial irradiation, relative to no adjuvant therapy for stage T1-2N0M0 SCLC. This National Cancer Data Base analysis was performed to determine the potential benefits of adjuvant chemotherapy with and without prophylactic cranial irradiation in patients who undergo complete resection for early-stage small-cell lung cancer. PATIENTS AND METHODS: Overall survival of patients with pathologic T1-2N0M0 SCLC who underwent complete resection in the National Cancer Data Base from 2003 to 2011, stratified by adjuvant therapy regimen, was evaluated using Kaplan-Meier and Cox proportional hazards analysis. Patients treated with induction therapy and those who died within 30 days of surgery were excluded from analysis. RESULTS: Of 1,574 patients who had pT1-2N0M0 SCLC during the study period, 954 patients (61%) underwent complete R0 resection with a 5-year survival of 47%. Adjuvant therapy was administered to 59% of patients (n = 566), including chemotherapy alone (n = 354), chemoradiation (n = 190, including 99 patients who underwent cranial irradiation), and radiation alone (n = 22). Compared with surgery alone, adjuvant chemotherapy with or without radiation was associated with significantly improved survival. In addition, multivariable Cox modeling demonstrated that treatment with adjuvant chemotherapy (hazard ratio [HR], 0.78; 95% CI, 0.63 to 0.95) or chemotherapy with radiation directed at the brain (HR, 0.52; 95% CI, 0.36 to 0.75) was associated with improved survival when compared with no adjuvant therapy. CONCLUSION: Patients with pT1-2N0M0 SCLC treated with surgical resection alone have worse outcomes than those who undergo resection with adjuvant chemotherapy alone or chemotherapy with cranial irradiation.

Should patients with laryngeal small cell neuroendocrine carcinoma receive prophylactic cranial irradiation?

While small cell neuroendocrine carcinomas (SCNCs) most often arise in the lung, extrapulmonary SCNCs arise in a variety of locations-including the head and neck region. In particular, laryngeal SCNCs-while rare tumors-are nevertheless recognized as distinct lesions. The rarity of laryngeal SCNC gives rise to two distinct difficulties: first (particularly with small biopsy specimens), laryngeal SCNC can be difficult to diagnose by routine light microscopy; second, limited experience with these tumors can make the crafting of a treatment plan for individual patients difficult. As regards the first problem, pathologic diagnosis is greatly enhanced by the application of immunohistochemistry. The second problem-crafting a successful treatment strategy-presents a much larger difficulty. It is tempting to extrapolate from experience with the (more common) pulmonary SCNC in search of a strategy applicable to laryngeal SCNC; such an extrapolation, however, may not be uniformly successful. In particular, while a combination of radiation therapy and chemotherapy appears to be as valuable in the treatment of extrapulmonary as it is in the treatment of pulmonary SCNC, prophylactic cranial irradiation (PCI)-which has enjoyed some success in the treatment of some patients with pulmonary SCNC-does not appear to have similar utility in patients with laryngeal SCNC. Accordingly, the use of PCI does not appear to have a role to play at this point in time in the treatment of patients with laryngeal SCNC.

c-Met inhibitors attenuate tumor growth of small cell hypercalcemic ovarian carcinoma (SCCOHT) populations.

A cellular model (SCCOHT-1) of the aggressive small cell hypercalcemic ovarian carcinoma demonstrated constitutive chemokine and growth factor production including HGF. A simultaneous presence of c-Met in 41% SCCOHT-1 cells suggested an autocrine growth mechanism. Expression of c-Met was also observed at low levels in the corresponding BIN-67 cell line (6.5%) and at high levels in ovarian adenocarcinoma cells (NIH:OVCAR-3 (84.4%) and SK-OV-3 (99.3%)). Immunohistochemistry of c-Met expression in SCCOHT tumors revealed a heterogeneous distribution between undetectable levels and 80%. Further characterization of SCCOHT-1 and BIN-67 cells by cell surface markers including CD90 and EpCAM demonstrated similar patterns with differences to the ovarian adenocarcinoma cells. HGF stimulation of SCCOHT-1 cells was associated with c-Met phosphorylation at Tyr1349 and downstream Thr202/Tyr204 phosphorylation of p44/42 MAP kinase. This HGF-induced signaling cascade was abolished by the c-Met inhibitor foretinib. Cell cycle analysis after foretinib treatment demonstrated enhanced G2 accumulation and increasing apoptosis within 72 h. Moreover, the IC50 of foretinib revealed 12.4 nM in SCCOHT-1 cells compared to 411 nM and 481 nM in NIH:OVCAR-3 and SK-OV-3 cells, respectively, suggesting potential therapeutic effects. Indeed, SCCOHT-1 and BIN-67 tumor xenografts in NODscid mice exhibited an approximately 10-fold and 5-fold reduced tumor size following systemic application of foretinib, respectively. Furthermore, foretinib-treated tumors revealed a significantly reduced vascularization and little if any c-Met-mediated signal transduction. Similar findings of reduced proliferative capacity and declined tumor size were observed after siRNA-mediated c-Met knock-down in SCCOHT-1 cells demonstrating that in vivo inhibition of these pathways contributed to an attenuation of SCCOHT tumor growth.

Circulating tumor cells correlate with recurrence in stage III small-cell lung cancer after systemic chemoradiotherapy and prophylactic cranial irradiation.

OBJECTIVE: We investigated the correlation between circulating tumor cells and the incidence of brain metastases as a first site of recurrence among patients with small-cell lung cancer after systemic chemoradiotherapy and prophylactic cranial irradiation. In addition, we assessed the contribution of circulating tumor cells for planning the appropriate total dose of prophylactic cranial irradiation for small-cell lung cancer. METHODS: Patients (n = 112) with diagnosed Stage III small-cell lung cancer were treated with four cycles of platinum-based regimen and concurrent chest irradiation, and then prophylactic cranial irradiation. Blood samples for circulating tumor cell analysis were obtained before the initiation of chemotherapy and after the first and fourth cycle of chemotherapy. RESULTS: Circulating tumor cells after the first cycle of chemotherapy correlated with tumor response after completion of chemotherapy (P = 0.012). Patients with brain as the first site suffered a higher rate of further metastases to other organs, and local recurrence, compared with those whose first site was the other organs (P < 0.001), and their survival rates were worse. Circulating tumor cells at baseline were the sole independent prognostic factor for specific progression-free survival. Receiver operating characteristic curves based on median specific progression-free survival revealed a circulating tumor cell cutoff at baseline of 218, and circulating tumor cells ≤218 at baseline correlated with significantly higher progression-free survival (P = 0.007), specific progression-free survival (P = 0.001) and overall survival (P = 0.001). CONCLUSIONS: Circulating tumor cells prior to the initiation of chemotherapy are a valuable predictor of specific progression-free survival in Stage III small-cell lung cancer. For patients with circulating tumor cells >218, prophylactic cranial irradiation at a total dose of 30 Gy in 15 fractions is insufficient.

Current approaches for prophylactic cranial irradiation in extrapulmonary small cell carcinoma.

BACKGROUND: Small cell lung cancer (SCLC) patients, who have achieved complete or partial response after chemotherapy, should be followed with prophylactic cranial irradiation (PCI). PCI for extrapulmonary small cell carcinoma (EPSCC) is not routinely recommended. The purpose of this review is to discuss all aspects of PCI in management of EPSCC. SCOPE: The PubMed database and the database of online abstracts of the American Society of Oncology (ASCO), ASCO Genitourinary (GU) Cancers meetings and clinical trials were searched up to 15 October 2013 using the following search keywords: 'SCC or EPSCC of each organ site and prophylactic cranial radiotherapy'. The language of screened abstracts and manuscripts was limited to English. The papers which included the largest case series and data of cases about prophylactic cranial radiotherapy and/or were published in the last 10 years were selected. FINDINGS: Many single center studies showed low incidence of brain metastasis in patients with esophageal small cell carcinoma (SCC). Due to the low incidence of brain metastasis, PCI is not recommended for esophageal SCC. Genitourinary, colorectal, small bowel and appendix cranial metastatic SCCs are extremely rare. Therefore, PCI is not recommended. The frequency of brain metastasis of prostate small cell carcinoma is much higher (16-19%) compared to other counterparts of EPSCC. PCI can be performed in selected cases of prostate SCC. High rates (41%) of brain metastasis develop in head and neck SCC. PCI should be considered for patients with head neck SCC. CONCLUSION: In the literature, the brain metastasis incidence of EPSCC might vary from 1.7% up to 40%. In many patients with ESPCC, PCI is not recommended. However, we have to keep in mind that primary head and neck and prostate SCC are exceptions due to the high incidence of cranial metastasis; PCI should be recommended for these patients on an individual basis.

Cerebral metastases in extrapulmonary cell carcinoma. Implications for the use of prophylactic cranial irradiation.

BACKGROUND AND PURPOSE: Extrapulmonary small cell carcinoma (EPSCC) is a rare disease. Standard treatment is performed in analogy to small cell lung cancer; however, due to the differences in rates of cerebral metastases (CM), prophylactic cranial irradiation (PCI) is not routinely used. Therefore, we evaluated the characteristics of all patients developing brain metastases in a population of EPSCC patients and calculated a number needed to treat (NNT) for the prevention of cerebral metastases by PCI. PATIENTS, METHODS, AND RESULTS: Of 51 patients treated at our institution from 1999-2011 for EPSCC, 11 presented with CM, 5 at initial diagnosis, 6 in the course of their disease. Median overall survival after primary diagnosis of EPSCC was 12 months. Overall survival after diagnosis of CM was significantly in favor of primarily cerebrally metastasized patients with 9 compared to 2 months for secondary CM (p = 0.04), median survival for all patients being 4 months. The NNT calculation was based on the 6 patients with secondary brain metastases in our series and a relative risk reduction of 60% observed in the studies of PCI for small cell lung cancer (SCLC), resulting in an NNT of 13. CONCLUSION: Although the frequency of brain metastases in EPSCC was lower than in SCLC, the NNT of 13 for the prevention of CM, as well as the poor median survival after diagnosis of secondary brain metastases of 2 months might be a reason to discuss and evaluate PCI for EPSCC patients responding to initial therapy.

Fruits and vegetables consumption and the risk of histological subtypes of lung cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC).

OBJECTIVE: To examine the association between fruit and vegetable consumption and risk of different histological subtypes of lung cancer among participants of the European Prospective Investigation into Cancer and Nutrition study. METHODS: Multivariable Cox proportional hazard models were used to analyze the data. A calibration study in a subsample was used to reduce dietary measurement errors. RESULTS: During a mean follow-up of 8.7 years, 1,830 incident cases of lung cancer (574 adenocarcinoma, 286 small cell, 137 large cell, 363 squamous cell, 470 other histologies) were identified. In line with our previous conclusions, we found that after calibration a 100 g/day increase in fruit and vegetables consumption was associated with a reduced lung cancer risk (HR 0.94; 95% CI 0.89-0.99). This was also seen among current smokers (HR 0.93; 95% CI 0.90-0.97). Risks of squamous cell carcinomas in current smokers were reduced for an increase of 100 g/day of fruit and vegetables combined (HR 0.85; 95% CI 0.76-0.94), while no clear effects were seen for the other histological subtypes. CONCLUSION: We observed inverse associations between the consumption of vegetables and fruits and risk of lung cancer without a clear effect on specific histological subtypes of lung cancer. In current smokers, consumption of vegetables and fruits may reduce lung cancer risk, in particular the risk of squamous cell carcinomas.

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 years), and interval between the start of induction treatment and the date of randomisation (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.

Dietary alpha-, beta-, gamma- and delta-tocopherols in lung cancer risk.

Studies of vitamin E and cancer have focused on the alpha-tocopherol form of the vitamin. However, other forms of vitamin E, in particular gamma-tocopherol may have unique mechanistic characteristics relevant to lung cancer prevention. In an ongoing study of 1,088 incident lung cancer cases and 1,414 healthy matched controls, we studied the associations between 4 tocopherols (alpha-, beta-, gamma-, and delta-tocopherol) in the diet and lung cancer risk. Using multiple logistic regression analysis, the adjusted odds ratios (OR) and 95% confidence intervals (CI) of lung cancer for increasing quartiles of dietary alpha-tocopherol intake were 1.0, 0.63 (0.50-0.79), 0.58 (0.44-0.76) and 0.39 (0.28-0.53), respectively (p-trend < 0.0001). For dietary intake of beta-tocopherol, the OR and 95% CI for all subjects were: 1.0, 0.79 (0.63-0.98), 0.59 (0.45-0.78) and 0.56 (0.42-0.74), respectively (p-trend < 0.0001). Similar results for dietary gamma-tocopherol intake were observed: 1.0, 0.84 (0.67-1.06), 0.76 (0.59-0.97) and 0.56 (0.42-0.75), respectively (p- trend = 0.0002). No significant association between delta-tocopherol intake and lung cancer risk was detected. When the 4 tocopherols were summed as total tocopherol intake, a monotonic risk reduction was also observed. When we entered the other tocopherols in our model, only the association with dietary alpha-tocopherol intake remained significant; i.e., increasing intake of dietary alpha-tocopherol accounted for 34-53% reductions in lung cancer risk. To the best of our knowledge, this is the first report of the independent associations of the 4 forms of dietary tocopherol (alpha-, beta-, gamma- and delta-tocohperol) on lung cancer risk. Given the limitations with case-control studies, these findings need to be confirmed in further investigations.

An update on the treatment of CNS metastases in small cell lung cancer.

Brain metastases occur frequently and are a significant threat to the quality of life in patients with small cell lung carcinoma. The primary treatment modality has historically been whole brain radiation, which can provide a moderate extension of life and improvement in neurologic symptoms. Despite increasing interest in the use of alternative therapeutic agents-primarily chemotherapy-these have yet to be demonstrated to be superior to radiation in management of brain metastasis. Prophylactic cranial irradiation prevents or delays the occurrence of brain metastases in patients with small cell lung carcinoma. Until recently, this benefit has been thought to be primarily restricted to a minority of patients with limited stage disease. A large European trial, however, has now shown a survival benefit to the use of prophylactic cranial irradiation in patients who have any response to systemic chemotherapy. This finding should significantly shift management practices for this aggressive disease for most patients.

Detection of brain metastases from small cell lung cancer: consequences of changing imaging techniques (CT versus MRI).

BACKGROUND: The aims of this study were to show 1) the effect of changing from computed tomography (CT) to magnetic resonance imaging (MRI) on the prevalence of detected brain metastases (BM) in patients with newly diagnosed small cell lung cancer (SCLC); 2) the difference in survival between patients with single and multiple BM; and 3) the effect of the change in patient labeling on eligibility for prophylactic brain irradiation. METHODS: From 1980 to 2004, 481 consecutive patients with SCLC were enrolled. Brain imaging was routinely performed after diagnosis of SCLC. At the start of 1991, MRI replaced CT in almost all patients. All patients were regularly examined by a neurologist. RESULTS: The prevalence of detected BM was 10% in the CT era and 24% in the MRI era. In the CT era, all detected BM were symptomatic, whereas in the MRI era, 11% were asymptomatic. In both periods, patients labeled as single BM survived longer than those labeled as multiple BM. For patients labeled as single BM or multiple BM, survival was longer in the MRI era than in the CT era. The proportion of patients who were eligible for prophylactic cranial irradiation was lower in the MRI era. CONCLUSIONS: The estimated prevalence of BM increases when MRI is used instead of CT. Patients with a detected single BM survive longer than patients with multiple BM. The apparently increased survival in the MRI era can be attributed to the "Will Rogers phenomenon". The use of MRI makes fewer patients eligible for prophylactic cranial irradiation.

Adjuvant whole brain radiotherapy: strong emotions decide but rational studies are needed.

Brain metastases are common in cancer patients and cause considerable morbidity and mortality. For patients with limited disease and good performance status, treatment typically involves a combination of focal measures (e.g., surgical resection or radiosurgery) for the radiographically apparent disease, followed by adjuvant whole brain radiotherapy (WBRT) to treat subclinical disease. Because of concerns regarding the toxicity of WBRT, especially neurocognitive deterioration, many have advocated withholding adjuvant WBRT. Recently published studies have shed more light on the efficacy of adjuvant WBRT and the neurocognitive effects of WBRT. However, the inclusion of neurocognitive and quality-of-life data in clinical trials are still required to better define the role of adjuvant WBRT. Currently, two Phase III trials are underway, one in Europe and one in North America, that will determine the effect of adjuvant WBRT on patients' quality of life, neurocognitive function, and survival.

Diffusion tensor imaging screening of radiation-induced changes in the white matter after prophylactic cranial irradiation of patients with small cell lung cancer: first results of a prospective study.

BACKGROUND AND PURPOSE: Diffusion tensor imaging (DTI) will show abnormal fractional anisotropy (FA) in the normal-appearing brain after prophylactic cranial irradiation (PCI). These abnormalities will be more accentuated in patients with underlying vascular risk factors. MATERIALS AND METHODS: A prospective study by use of DTI and conventional T2-weighted MR images was performed with a 1.5T unit with 16 patients with small cell lung cancer and undergoing PCI. All of the T2-weighted images were evaluated with respect to abnormalities in signal intensity of white matter as markers of radiation damage. Measurements of FA were performed before, at the end of, and 6 weeks after radiation therapy. On the FA maps, the bifrontal white matter, the corona radiata, the cerebellum, and the brain stem were evaluated. FA values were compared with respect to age, demographic, and vascular risk factors. Statistical analyses (Friedman test, Wilcoxon test, and Mann-Whitney U test) were performed. RESULTS: Fractional anisotropy decreased significantly in supratentorial and infratentorial normal-appearing white matter from the beginning to the end of PCI (P < .01). A further decline in FA occurred 6 weeks after irradiation (P < .05). A stronger reduction in FA was observed in patients with more than 1 vascular risk factor. There was an age-related reduction of white matter FA. Patients 65 years and older showed a trend toward a stronger reduction in FA. CONCLUSION: During the acute phase, after PCI, patients with many vascular risk factors showed stronger damage in the white matter compared with patients with only 1 risk factor.

E7080, a novel inhibitor that targets multiple kinases, has potent antitumor activities against stem cell factor producing human small cell lung cancer H146, based on angiogenesis inhibition.

E7080 is an orally active inhibitor of multiple receptor tyrosine kinases including VEGF, FGF and SCF receptors. In this study, we show the inhibitory activity of E7080 against SCF-induced angiogenesis in vitro and tumor growth of SCF-producing human small cell lung carcinoma H146 cells in vivo. E7080 inhibits SCF-driven tube formation of HUVEC, which express SCF receptor, KIT at the IC(50) value of 5.2 nM and it was almost identical for VEGF-driven one (IC(50) = 5.1 nM). To assess the role of SCF/KIT signaling in tumor angiogenesis, we evaluated the effect of imatinib, a selective KIT kinase inhibitor, on tumor growth of H146 cells in nude mice. Imatinib did not show the potent antitumor activity in vitro (IC(50) = 2,200 nM), because H146 cells did not express KIT. However, oral administration of imatinib at 160 mg/kg clearly slowed tumor growth of H146 cells in nude mice, accompanied by decreased microvessel density. Oral administration of E7080 inhibited tumor growth of H146 cells at doses of 30 and 100 mg/kg in a dose-dependent manner and caused tumor regression at 100 mg/kg. While anti-VEGF antibody also slowed tumor growth, it did not cause tumor regression. These results indicate that KIT signaling has a role in tumor angiogenesis of SCF-producing H146 cells, and E7080 causes regression of H146 tumors as a result of antiangiogenic activity mediated by inhibition of both KIT and VEGF receptor signaling. E7080 may provide therapeutic benefits in the treatment of SCF-producing tumors.