A meta-analysis of thoracic radiotherapy for small-cell lung cancer

Effects of thoracic radiotherapy timing and duration on progression-free survival in limited-stage small cell lung cancer

Concurrent chemoradiotherapy (CRT) has been recommended and applied widely as the standard treatment for limited‐stage small cell lung cancer (LS‐SCLC). However, controversies remain regarding the optimal timing and treatment duration of thoracic radiotherapy (TRT), and their effects on patient survival. To evaluate prognostic values of TRT timing and duration on progression‐free survival (PFS) in LS‐SCLC and their dependence on TRT fractionation and clinicopathological characteristics, we retrospectively analyzed 197 LS‐SCLC patients receiving CRT from 2000 to 2016 at Sun Yat‐sen University Cancer Center. Based on the optimal cut‐off values of TRT timing and duration generated by Cutoff Finder, patients were divided into early TRT/late TRT group and short TRT/long TRT group respectively. Univariate and multivariate Cox analysis were performed to assess correlations of TRT timing, duration, fractionation, and clinicopathological characteristics with PFS. Univariate analysis revealed that early‐initiated TRT (P = 2.54 × 10⁻⁴) and short TRT (P = .001) significantly correlated with longer PFS. Their PFS benefits persisted in patients receiving hyperfractionated TRT and etoposide‐cisplatin (EP) chemotherapy, but were less prominent in those receiving once‐daily TRT and non‐EP chemotherapy. Multivariate analysis further identified early initiated TRT (P = .004) and short TRT (P = .017) as independent prognostic factors for longer PFS in LS‐SCLC. Our study confirmed that early‐initiated TRT and short TRT had positive prognostic roles in LS‐SCLC, especially in patients receiving hyperfractionated TRT and etoposide‐cisplatin chemotherapy. TRT fractionation was not an independent prognostic factor in LS‐SCLC.

Guideline for the Initial Management of Small Cell Lung Cancer (Limited and Extensive Stage) and the Role of Thoracic Radiotherapy and First-line Chemotherapy

AIMS

We investigated the efficacy of adding radiotherapy to chemotherapy in patients with extensive stage small cell lung cancer (ES-SCLC) and the appropriate timing, dose and schedule of treatment for patients with ES-SCLC or limited stage SCLC (LS-SCLC).

MATERIALS AND METHODS

The guideline was developed by Cancer Care Ontario's Program in Evidence-Based Care and by the Lung Cancer Disease Site Group through a systematic review of randomised controlled trials.

KEY RECOMMENDATIONS

In patients with LS-SCLC (stage I, II and III), the addition of thoracic radiotherapy to standard chemotherapy is recommended. However, there is no clear evidence to inform definitive recommendations for optimal timing, sequential versus concurrent therapies and optimal dose or regimen. In patients with LS-SCLC, etoposide-cisplatin is the preferred regimen for adults who are being treated with combined modality therapy with curative intent. In patients with ES-SCLC (stage IV), there is insufficient evidence to recommend the addition of thoracic radiotherapy to standard chemotherapy as a standard practice for survival benefit; however, it could be considered on a case-by-case basis to reduce local recurrence. In patients with ES-SCLC, a platinum agent plus etoposide is the preferred regimen for adult patients who are being treated with combined modality therapy. Cisplatin and irinotecan represents an alternative treatment option to this, but is associated with increased rates of adverse events such as diarrhoea.

Preliminary Results about Application of Intensity-Modulated Radiotherapy to Reduce Prophylactic Radiation Dose in Limited-Stage Small Cell Lung Cancer

To evaluate the clinical outcomes of simultaneous dose reduction of elective nodal area with intensity-modulated radiotherapy (SIR-IMRT) versus conventional IMRT (C-IMRT) in patients with limited-stage small-cell lung cancer (LS-SCLC), patients with LS-SCLC who received definitive SIR-IMRT or C-IMRT were retrospectively analyzed. In SIR-IMRT group, the prescribed dose was 60Gy to the planning gross target volume (PTV_G), and 54Gy to the planning target volume (PTV). In the C-IMRT group, the prescribed dose was 60Gy to the whole PTV. Radiation-related toxicities were estimated according to Common Terminology Criteria for Adverse Events (version 3.0). The primary endpoint was loco-regional recurrence-free survival (LRFS), and the secondary endpoints include overall survival (OS) and toxicities. LRFS and OS were estimated with Kaplan-Meier method. After propensity score matching, 84 patients were included in this study, with 42 patients in each group. Fifty-eight patients experienced treatment failure. Grade 3 and above radiation-induced lung toxicity developed in 2 patients in SIR-IMRT group and 5 patients in C-IMRT group, respectively. Grade 3 and above radiation-related esophagitis was observed in 3 patients and 5 patients, respectively. The 1-, 3-year LRFS rates of the SIR-IMRT group and C-IMRT group were 90.4%, 73.3% and 87.1%, 45.0%(P=0.025), respectively. Reducing the irradiation dose to the elective nodal region may reduce radiation-induced toxicities without compromising local-regional control and overall survival.

Cardiac mortality in limited-stage small cell lung cancer

INTRODUCTION

Life expectancy of patients with limited-stage small cell lung cancer (LS-SCLC) continues to rise; thus, characterization of long-term toxicities is essential. Although there are emerging data linking cardiac irradiation doses with survival for non-small cell lung cancer, there are currently minimal data on cardiac-specific mortality (CSM) in LS-SCLC. The goal of this investigation was to evaluate CSM between left- and right-sided cases.

METHODS

The Surveillance, Epidemiology, and End Results database was queried for stage I-III primary SCLC patients receiving radiotherapy; CSM was compared between left- and right-sided diseases. Accounting for mortality from other causes, Gray's test compared cumulative incidences of CSM between both groups. Multiple multivariate models examined the independent effect of laterality on CSM, including the Fine and Gray competing risk model and the Cox proportional hazards model.

RESULTS

Of 19,692 patients, 7991 (41%) were left-sided and 11,701 (59%) were right-sided. Left-sided patients experienced significantly higher CSM overall (3.3% vs. 2.6%, p = 0.004). Laterality was an independent predictor of CSM in the overall population in the Fine and Gray competing risk model (p = 0.006) as well as the Cox proportional hazards model (p = 0.007). The overall hazard ratio for CSM by disease laterality was 1.27 (95% confidence interval, 1.08-1.50). Laterality had no statistical association with non-cardiac mortality in the Fine and Gray competing risk model (p = 0.130).

CONCLUSIONS

Although causation between radiotherapy and CSM in LS-SCLC cannot be stated based on these data, we encourage clinical attentiveness to cardiac-sparing radiotherapy for LS-SCLC, along with further investigation evaluating dosimetric correlates for cardiotoxicity.

Hematologic variables associated with brain failure in patients with small-cell lung cancer

BACKGROUND AND PURPOSE

We sought factors associated with the development of brain metastases after treatment of small cell lung cancer (SCLC) in patients without brain involvement at diagnosis.

METHODS

We analyzed 293 patients with SCLC without brain metastases who received chemotherapy, thoracic radiation therapy (TRT), or both in 2001-2015. Pretreatment hematologic markers (platelet count, neutrophil count, lymphocyte count, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, and lactate dehydrogenase) and other clinical characteristics were evaluated for correlation with brain metastases-free survival (BMFS). Cutoffs were established with receiver operating characteristics curves. Factors significant in univariate analysis were used to build a multivariate Cox model for BMFS.

RESULTS

Median follow-up time was 14.3 months. Brain metastases developed in 115 patients (39%)-32% of those with low pretreatment platelet counts (PPC) (≤270 × 10⁹/L) and 46% of those with high PPC (>270 × 10⁹/L). Median BMFS time for all patients was 27.9 months. Two-year BMFS rates were worse for patients with high PPC (14.6% vs. 22.1% low, P = 0.009). High PPC was independently associated with inferior BMFS (P = 0.038), as were receipt of TRT <45 Gy and no prophylactic cranial irradiation (both P < 0.001).

CONCLUSIONS

High PPC was associated with increased rates of brain metastasis in patients with SCLC with no evidence of brain disease at diagnosis.

Timing of Thoracic Radiation Therapy With Chemotherapy in Limited-stage Small-cell Lung Cancer: Survey of US Radiation Oncologists on Current Practice Patterns

INTRODUCTION

For limited-stage small-cell lung cancer (LS-SCLC), National Comprehensive Cancer Network guidelines recommend that thoracic radiotherapy (TRT) be delivered concurrently with chemotherapy and early in the regimen, with cycle 1 or 2. Evidence is conflicting regarding the benefit of early timing of TRT. A Korean randomized trial did not see a survival difference between early (cycle 1) and late (cycle 3) TRT. Current United States (US) practice patterns are unknown.

MATERIALS AND METHODS

We surveyed US radiation oncologists using an institutional review board-approved online questionnaire. Questions covered treatment recommendations, self-rated knowledge of trials, and demographics.

RESULTS

We received 309 responses from radiation oncologists. Ninety-eight percent recommend concurrent chemoradiotherapy over sequential. Seventy-one percent recommend starting TRT in cycle 1 of chemotherapy, and 25% recommend starting in cycle 2. In actual practice, TRT is started most commonly in cycle 2 (48%) and cycle 1 (44%). One-half of respondents (54%) believe starting in cycle 1 improves survival compared with starting in cycle 3. Knowledge of the Korean trial was associated with flexibility in delaying TRT to cycle 2 or 3 (P = .02). Over one-third (38%) treat based on pre-chemotherapy volume.

CONCLUSION

US radiation oncologists strongly align with National Comprehensive Cancer Network guidelines, which recommend early concurrent chemoradiotherapy. Nearly three-quarters of respondents prefer starting TRT with cycle 1 of chemotherapy. However, knowledge of a trial supporting a later start was associated with flexibility in delaying TRT. Treating based on pre-chemotherapy volume-endorsed by over one-third of respondents-may add unnecessary toxicity. This survey can inform development of future trials.

Lung Cancer: Posttreatment Imaging: Radiation Therapy and Imaging Findings

Over the last few decades, advances in radiation therapy technology have markedly improved radiation delivery. Advancements in treatment planning with the development of image-guided radiotherapy and techniques such as proton therapy, allow precise delivery of high doses of radiation conformed to the tumor. These advancements result in improved locoregional control while reducing radiation dose to surrounding normal tissue. The radiologic manifestations of these techniques can differ from radiation induced lung disease seen with traditional radiation therapy. Awareness of these radiologic manifestations and correlation with radiation treatment plans are important to differentiate expected radiation induced lung injury from recurrence, infection and drug toxicity.

Comorbidity as a Prognostic Factor in Small Cell Lung Cancer

Aims and Background

Many factors have prognostic significance in small cell lung cancer (SCLC). The aim of this study was to define the prognostic factors influencing the response to therapy and the survival in SCLC.

Methods

A consecutive series of 90 patients with SCLC was analyzed retrospectively using 32 pretreatment and 3 treatment-related prognostic factors with respect to their influence on survival. Prognostic factors were evaluated by univariate analysis and by the Cox multivariate regression model. Patients who survived more than 2 months were included in the univariate analysis.

Results

The median survival of the whole population was 7 months, with a 1-year survival rate of 20%. In univariate analysis, prognosis was significantly influenced by gender, comorbidity, thoracic irradiation, receipt of more than 3 cycles of chemotherapy, response to chemotherapy, and performance status. The Cox model identified comorbidity (P = 0.03), receipt of more than 3 cycles of chemotherapy (P = 0.003) and response to chemotherapy (P = 0.002) as the only significant factors.

Conclusions

The prognosis of SCLC is poor, and comorbidity information should be included in prognostic studies.

High-dose Chemotherapy in Small Cell Lung Cancer

Improvements in small cell lung cancer (SCLC) therapy with conventional doses of drugs with or without radiotherapy have been poor, and the 5-year survival is discouraging. Since SCLC is highly sensitive to radiotherapy and chemotherapy, some studies have tried to improve survival by increasing the dose of the drugs. Within conventional ranges, dose intensity can be increased with the support of hematopoietic growth factors (G/GM-CSF) and/or shortening treatment intervals (eg weekly regimens). However, dose intensity could be increased by only 20-30% and a survival advantage was not definitively obtained. Given its high chemosensitivity already two decades ago, SCLC was one of the first malignancies deemed suitable for maximizing dose and dose intensity with the support of autologous bone marrow transplantation (ABMT). On the whole, results were disappointing and the procedure was nearly abandoned. Nowadays, some interest is emerging again due to the improvements in supportive care such as the availability of hematopoietic growth factors and the peripheral blood progenitor cells (PBPC).

Extrapulmonary Small Cell Carcinoma: Multimodality Treatment Results

Aims and Background

Extrapulmonary small cell carcinoma is a distinct entity that can occur in many sites, and it is pathologically similar to small-cell lung cancer. We report the results of a retrospective study of a multimodality treatment of 16 consecutive patients with a diagnosis of extrapulmonary small-cell carcinoma.

Methods

Primary tumor site was prostate in 2, gallbladder in 2, uterine cervix in 2, liver in 2, endometrium in 1, epididymis in 1, colon in 1, larynx in 1, breast in 1, and unknown primary tumor in 3 patients. Patients’ ages ranged from 19 to 79 years (median, 62). Nine patients had limited and 7 had extensive disease. Histologically, 14 were pure extrapulmonary small-cell carcinoma and 2 were mixed with squamous-cell carcinoma.

Results

Curative surgery was attempted in 8 patients. Seven patients received local-regional adjuvant radiotherapy. All patients, except the one with a breast primary, were treated with chemotherapy (mostly platinum-based regimens). Overall survival for all patients was 41% and 11% at 2 and 5 years, respectively (median survival, 14 months). Median survival for patients with limited disease was 25 months compared to 12 months for patients with extensive disease (P = 0.05).

Conclusions

Treatment results for extrapulmonary small-cell carcinoma are comparable to those of small-cell carcinomas of the lung. Extent of disease is a significant prognostic factor for survival.

Combined Modality Treatment of Locally Advanced Lung Cancer

This paper describes the mechanisms of action of ionizing radiations combined with antineoplastic drugs. Some relevant drugs for the combined modality treatments of locally advanced lung cancer are reported. The meta-analyses including randomized trials comparing single agent (radiotherapy or chemotherapy) versus combined chemoterapy and radiotherapy in patients with unresectable non small cell lung cancer and limited small cell lung cancer are then reviewed. The clinical outcome in relation to different schedules of chemoradiotherapy (sequential, alternating and concurrent) is also focussed.

Efficacy of prophylactic cranial irradiation in patients with limited-disease small-cell lung cancer who were confirmed to have no brain metastasis via magnetic resonance imaging after initial chemoradiotherapy

Background

Prophylactic cranial irradiation (PCI) is recommended for patients with limited-disease small-cell lung cancer (LD-SCLC) who achieved good response to definitive chemoradiotherapy. However, most clinical studies lacked brain imaging scans before PCI. Our study aimed to investigate whether PCI has a survival benefit in patients who have no brain metastases (BM) confirmed via magnetic resonance imaging (MRI) before PCI.

Results

Eighty patients were included in this study. Sixty patients received PCI (PCI group) and 20 patients did not (non-PCI group). OS was not significantly different between the two groups. The median OS time was 4.3 years (95% CI: 2.6 years–8.6 years) in the PCI group and was not reached (NR) (95% CI: 1.9 years–NR) in the non-PCI group (p = 0.542). Moreover, no differences were observed in the 3-year rates of PFS (46.2% and 44.4%, p = 0.720) and cumulative incidence of BM (24.0% vs. 27%, p = 0.404).

Conclusions

Our result suggests that PCI may not have a survival benefit in patients with LD-SCLC confirmed to have no BM after initial therapy, even if patients achieve a good response to definitive chemoradiotherapy.

Patients and Methods

We retrospectively evaluated patients with LD-SCLC who were confirmed to have no BM via MRI after initial chemoradiotherapy at the Shizuoka Cancer Center between September 2002 and August 2015. The overall survival (OS), progression-free survival (PFS), and cumulative incidence of BM were estimated using the Kaplan–Meier method between patients who received PCI and those who did not. Propensity score matching was used to balance baseline characteristics.

Proton therapy for small cell lung cancer

The prognosis of limited-stage small cell lung cancer (LS-SCLC) continues to improve and is now roughly comparable to that of locally advanced non-small cell lung cancer (NSCLC). This shift, taken together with the decreased toxicities of modern radiotherapy (RT) for LS-SCLC compared with those reported in historical trials, necessitates further evaluation of whether proton beam therapy (PBT) could further reduce both acute and late toxicities for patients receiving concurrent chemoradiotherapy for LS-SCLC. These notions are discussed theoretically, with an emphasis on cardiac events. This is followed by a review of the published evidence to date demonstrating improved dosimetry with PBT over intensity-modulated RT and encouraging safety and efficacy profiles seen in early clinical reports. In addition to covering technical aspects of PBT for LS-SCLC such as intensity-modulated PBT, image-guidance for PBT, and adaptive planning, this review also discusses the need for increased data on intensity-modulated PBT for LS-SCLC, economic and quality of life analyses for future PBT SCLC studies, careful categorization of cardiac events in these patients, and the role for immunotherapy combined with photon- or proton-based RT for LS-SCLC.

Selection of candidates for surgery as local therapy among early-stage small cell lung cancer patients: a population-based analysis

Background

Surgery and radiotherapy are considered local therapies for small cell lung cancer (SCLC). The present study aimed to select candidates for surgery as local therapy among patients with stage I or II SCLC, based on the eighth edition of the TNM classification for lung cancer.

Methods

Patients diagnosed with SCLC between 2004 and 2013 were selected from the Surveillance, Epidemiology, And End Results database. The TNM stage of SCLC in these patients was re-classified according to the eighth edition of the TNM classification for lung cancer. Patients with stage I or II SCLC were included in the present study. Overall survival (OS) and lung cancer-specific survival (LCSS) were separately compared in the different TNM stages between patients who received surgery and radiotherapy as local therapy. Multivariate analysis was applied to evaluate multiple factors associated with survival.

Results

Among the 2129 patients included in the present study, 387 (18.2%) received surgery, 1032 (48.5%) underwent radiotherapy as local therapy, 154 (7.2%) underwent surgery and radiotherapy, and 556 (26.1%) did not undergo either surgery or radiotherapy. Among patients with T1-2N0 (tumor size ≤ 50 mm without positive lymph nodes) disease, patients who underwent surgery had higher 5-year OS and LCSS rates than patients who received radiotherapy (T1N0: 46.0% vs. 23.8%, P < 0.001, and 58.4% vs. 36.4%, P < 0.001, respectively; T2N0: 42.6% vs. 24.7%, P = 0.004, and 48.8% vs. 31.3%, P = 0.011, respectively). Multivariate analysis results revealed that surgery was associated with low risk of death. However, among T3N0 or T1-2N1 (stage IIB) SCLC patients, patients who underwent surgery did not have higher 5-year OS and LCSS rates than patients who received radiotherapy (T3N0: 16.2% vs. 26.5%, P = 0.085, and 28.7% vs. 30.9%, P = 0.372, respectively; T1-2N1: 20.3% vs. 29.0%, P = 0.146, and 25.6% vs. 35.5%, P = 0.064, respectively).

Conclusions

Based on the assumption that the overwhelming majority of stage I or II SCLC patients who underwent surgery or radiotherapy also received certain types of systemic therapy, only patients with T1-2N0 SCLC may benefit from surgery as local therapy. Patients with T3N0 or T1-2N1 SCLC may consider radiotherapy as local therapy.

Effect of sequential chemoradiotherapy in patients with limited-disease small-cell lung cancer who were ineligible for concurrent therapy: a retrospective study at two institutions

Background

The standard treatment for limited-disease small-cell lung cancer (LD-SCLC) is a combination of chemotherapy and concurrent thoracic radiotherapy. In selected cases, sequential radiotherapy is preferred because of the need for a large irradiation field, patient age, comorbidities or performance status. Nevertheless, the efficacy of sequential chemoradiotherapy in patients in whom concurrent chemoradiotherapy is contraindicated is not well known.

Methods

We retrospectively analyzed 286 patients with LD-SCLC at two institutions in Japan between 2000 and 2014. We compared the clinical characteristics and treatment outcomes of patients undergoing sequential radiotherapy with those undergoing concurrent radiotherapy.

Results

One hundred and seventy-five patients received concurrent chemoradiotherapy, 33 received sequential chemoradiotherapy and 46 received chemotherapy only. The median patient age was 64 years (range, 18-82 years) for the concurrent group and 71 years (49-82 years) for the sequential group. Conventional radiotherapy was selected more frequently than accelerated hyperfractionated radiotherapy (27 patients [82%] with conventional radiotherapy, and six patients [18%] with hyperfractionated radiotherapy). The major reasons for the selection of sequential radiotherapy were advanced age (12 patients) and a large irradiation field (11 patients). The median overall survival time was 41.1 months for the sequential group and 38.1 months for the concurrent group. The 5-year survival rates were 36.0% for the sequential group and 41.6% for the concurrent group.

Conclusions

In clinical situation, since the treatment outcomes for patients with sequential radiotherapy were comparable to those receiving concurrent radiotherapy, sequential chemoradiotherapy can be a choice for the treatment of patients who are not candidates for concurrent chemoradiotherapy.

Impact of radiation dose on concurrent chemoradiotherapy for limited-stage small-cell lung cancer

Purpose

To evaluate clinical outcomes according to radiation dose in patients with limited-stage small-cell lung cancer (LS-SCLC) treated with concurrent chemoradiotherapy (CCRT).

Materials and Methods

From January 2006 to December 2015, 38 patients with LS-SCLC were treated with CCRT with etoposide and cisplatin. Total radiation doses ranged from 45 Gy to 66 Gy (1.8–2 Gy/fraction) and were classified into three groups: 45–54 Gy, 60–63 Gy, and 66 Gy. The impact of radiation dose on survival outcomes were evaluated. Toxicities were evaluated according to the Common Terminology Criteria for Adverse Events version 4.03.

Results

The median follow-up period was 21 months. The 2-year overall survival (OS) and local failure-free survival (LFFS) rates were 45.8% and 67.5%, respectively. The 2-year LFFS rates were 33.3% for 45–54 Gy group, 68.6% for 60–63 Gy group, and 87.1% for 66 Gy group (p = 0.014). In multivariate analysis, radiation dose was a significant factor for LFFS (p = 0.015). Although radiation dose was not a significant factor for OS and disease-free survival (DFS) in multivariate analysis, both OS and DFS of 66 Gy group tended to be better than that of 45–63 Gy group in univariate analysis. However, there were no differences in severe toxicities among three groups.

Conclusion

Higher radiation dose achieved better local control in patients with LS-SCLC treated with CCRT. In addition, a total dose of 66 Gy tended to improve OS and DFS.

The Cytoreductive Effect of Radiotherapy for Small Cell Ovarian Carcinoma of the Pulmonary Type: A Case Report and Review of the Literature

Small cell ovarian carcinoma of the pulmonary type is a rare and highly aggressive tumor for which a suitable treatment strategy has not been established. A 45-year-old woman presented with abdominal swelling, and primary ovarian carcinoma was suspected. The postoperative pathological diagnosis was small cell ovarian carcinoma of the pulmonary type. She also had complicated grade 1 endometrioid carcinoma of the uterine corpus. Three courses of cisplatin and etoposide therapy were administered as adjuvant chemotherapy. Because the tumor was chemotherapy resistant, she underwent palliative abdominal irradiation at a dose of 26 Gy in 13 fractions, which induced cytoreduction and provided symptomatic relief. She died 4 months after surgery. Lactate dehydrogenase was a useful tumor marker during treatment. Here, we present an extremely rare case of a patient with small cell ovarian carcinoma of the pulmonary type treated with radiotherapy after surgery and chemotherapy.

Grape seed procyanidin extract against lung cancer: the role of microrna-106b, bioavailability, and bioactivity

MiR-106b is an oncomir and a potential target for anti-cancer therapy. We hypothesize that grape seed procyanidin extract (GSE) exerts antineoplastic effects on lung cancer through modulations of miR-106b and its downstream target. We found that GSE significantly down-regulated miR-106b in a variety of lung neoplastic cells and increased cyclin-dependent kinase inhibitor 1A (CDKN1A) mRNA and protein (p21) levels. Transfection of miR-106b mimics reversed the up-regulations of CDKN1A mRNA and p21, abrogated the GSE induced anti-proliferative and anti-invasive properties in lung cancer cells. Oral gavage of leucoselect phytosome (LP), a standardized GSE to athymic nude mice down-regulated MIR106B mRNA and miR-106b expressions, and increased CDKN1A mRNA expression in tumor xenografts, correlating to significant reduction of tumor growth. To assess bioavailability, GSE and metabolites in plasma levels, between 60-90 minutes after gavage of LP were measured by LC/MS at treatment week 4 and 8. A novel bioactivity assay was also developed using lung homogenates from treated mice co-cultured with human lung cancer cells. LP-treated mouse lung homogenates significantly reduced proliferations of various lung cancer cells. Our findings reveal novel antineoplastic mechanisms by GSE, further define the pharmacokinetics and pharmacodynamics of LP, and support the continued investigation of LP against lung cancer.

Current and future therapeutic approaches for the treatment of small cell lung cancer

INTRODUCTION

Small-cell lung cancer (SCLC) is a very aggressive disease characterized by a high response rate to first-line chemotherapy, but most patients relapse within 1 year with disappointing results to second-line treatments. Chemotherapy has reached a plateau of effectiveness and new therapeutic strategies are needed to change the natural history of SCLC. Areas covered: This review will focus on the current results and the future development of the therapeutic approaches for the treatment of SCLC. Expert commentary: Immunotherapy is becoming a new frontier for the management of SCLC with preliminary interesting results. To date, no targeted drugs have been approved for clinical practice but several novel agents are in an advanced stage of clinical development in SCLC.

Better cancer specific survival in young small cell lung cancer patients especially with AJCC stage III

It has been reported that younger patients with non-small cell lung cancer (NSCLC) tend to have a better prognosis. Yet, few studies have focused on the clinicopathological characteristics and prognosis of young small cell lung cancer (SCLC), especially for patients with age < 50. In our study, we used Surveillance, Epidemiology, and End Results (SEER) population-based data and identified 16503 patients with SCLC including 711 patients aged < 50, 3338 patients aged 50-59, 5937 patients aged 60-69, 4649 patients aged 70-79 and 1868 patients aged ≥ 80 between 2010 and 2013. The Kaplan-Meier methods was used to develop the survival curve, and the results showed that the SCLC patients with aged < 50 tended to a better over survival (OS) and cancer specific survival (CSS) (all, P < 0.001). In addition, Cox regression model was used to analyze survival prognosis factors and perform subgroup analysis. The results showed that age was an independent prognostic factor for CSS (P < 0.001). Importantly, we found that for the patients with AJCC stage III subgroup, the age < 50 had apparent CSS benefit compared with any other age group (all, P < 0.01). Interestingly, for the patients with no surgery, radiation and no radiation subgroup, the age < 50 had no apparent CSS benefit only compared with age 50-59 (all, P > 0.05). In conclusion, our study demonstrated that the SCLC patients with aged < 50 tended had a better survival benefit, especially for patients with AJCC stage III.

Radiation therapy in small cell lung cancer: a national Italian survey

INTRODUCTION

Radiation therapy plays an important role in the management of SCLC both in curative and palliative setting, however, conflicting data from clinical trials incite debate over the appropriate use of radiation therapy regarding prophylactic cranial irradiation (PCI) and/or thoracic consolidative in extensive-stage SCLC (ES-SCLC). This survey is conducted to evaluate the current pattern of care among Italian radiation oncologists.

METHODS

In June 2016, all Italian radiation oncologists were invited to a web-based survey. The survey contained 34 questions regarding the role of RT in SCLC. Questions pertaining the role of RT in the clinical management of both limited-stage (LS) and ES-SCLC were included.

RESULTS

We received 48 responses from Italian radiation oncologists. More than half of respondents had been practicing for more than 10 years after completing residency training and 55% are subspecialists in lung cancer. Preferred management of LS-SCLC favored primary concurrent chemoradiotherapy (89%), even if the 36.9% usually delivered RT during or after the cycle 3 of chemotherapy, due to organizational issues. The most common dose and fractionation schedule in this setting was 60 Gy in 30 once-daily fractions. Furthermore, almost all respondents recommended PCI in patients with LS-SCLC. For ES-SCLC scenario, chemotherapy was defined the standard treatment by all respondents. PCI was recommended in ES-SCLC patients with thoracic complete remission (63% of respondents), with thoracic partial response (45%) and with thoracic stable disease (17%) after first-line chemotherapy. Lastly, the thoracic consolidative RT was recommended by 51% of respondents in patients with ES-SCLC in good response after first-line chemotherapy and a great variability was shown in clinical target volume definition, doses and fractionation schedules.

CONCLUSIONS

Our analysis showed a high adherence to current guidelines among the respondents in regard to chemoradiation approach in LS-SCLC patients and to PCI indications and doses. The great variability in radiation therapy doses and volumes in the thoracic consolidative radiotherapy in ES-SCLC is concerning. Future clinical trials are needed to standardize these treatment approaches to improve treatment outcomes among patients with ES-SCLC.

Imaging of Radiation Treatment of Lung Cancer

Radiation therapy is an important modality in the treatment of patients with lung cancer. Recent advances in delivering radiotherapy were designed to improve loco-regional tumor control by focusing higher doses on the tumor. More sophisticated techniques in treatment planning include 3-dimensional conformal radiation therapy, intensity-modulated radiotherapy, stereotactic body radiotherapy, and proton therapy. These methods may result in nontraditional patterns of radiation injury and various radiologic appearances that can be mistaken for recurrence, infection and other lung diseases. Knowledge of radiological manifestations, awareness of new radiation delivery techniques and correlation with radiation treatment plans are essential in order to correctly interpret imaging in these patients.

Setting the IMPACT (IMProve Access to Clinical Trial data) Observatory baseline

INTRODUCTION

The aim of the IMPACT (IMProving Access to Clinical Trial data) Observatory is to assess the transformation of clinical trials (CT) related to the evolution of sharing of CT data. The objective of this study is to establish a baseline for monitoring CT data sharing by the Observatory.

MATERIALS AND METHODS

In this scoping review we searched for publications that address sharing, dissemination, transparency or reuse of CT data published prior to December 31st 2000. Two authors screened titles and abstracts of 1204 records received by Medline searches and added 47 publications from direct discovery. Four researchers extracted, coded, and analyzed the predefined information from 102 selected papers.

RESULTS

We found a growing recognition of the importance of data sharing prior to 2001. However, there were numerous obstacles including the ambiguity of the concept of data sharing, the absence of specific terminology and the lack of an "open" culture. By the end of 2000, data, metadata, and evidence based medicine were defined. Data sharing, registries, databases and re-analyses of individual patient data (IPD) emerged. The use of systematic reviews and IPD meta-analysis in decision making was promoted. Most arguments for broader data sharing came from oncology, paediatrics, rare diseases, AIDS, pregnancy, perinatal medicine, and media reporting related scandals.

CONCLUSIONS

Our findings indicate that the year 2000 could be used as a baseline for monitoring the evolution of CT data sharing as basic prerequisites were set in place, including greater understanding that CT data sharing is essential for decision making and the advancements of the Internet.

Prognostic significance of pretreatment total lymphocyte count and neutrophil-to-lymphocyte ratio in extensive-stage small-cell lung cancer

BACKGROUND

We evaluated pretreatment total lymphocyte count (TLC, marker of immunosuppression), neutrophil-to-lymphocyte ratio (NLR, marker of inflammation), and overall survival (OS) in patients with extensive-stage small-cell lung cancer (ES-SCLC).

METHODS

Pretreatment blood characteristics, age, sex, performance status, race, stage (M1a vs. M1b), number and location of metastases, weight loss, smoking status, chemotherapy cycles (<4 vs. ≥4), thoracic radiotherapy dose (<45 vs. ≥45 Gy), and receipt of prophylactic cranial irradiation (PCI) were evaluated in 252 patients with ES-SCLC treated in 1998-2015. Factors significant in univariate analysis were selected as covariates for a multivariate Cox model.

RESULTS

Pretreatment TLC was below normal (<1.0 × 10³/µL) in 58 patients (23%). Median OS time was 11.0 months and was worse for those with TLC ≤ 1.5 × 10³/µL (9.8 vs. 12.0 months) and pretreatment NLR > 4.0 (9.4 vs. 13.9 months). Multivariate analysis identified low TLC (hazard ratio [HR] 0.734, 95% confidence interval [CI] 0.565-0.955, P = 0.021) and high NLR (HR 1.521, 95% CI 1.172-1.976, P = 0.002) as predicting inferior survival. Age (>63 y), sex (male), performance status (≥2), chemotherapy cycles (<4), radiation dose (<45 Gy), and no PCI also predicted worse OS (P < 0.05).

CONCLUSIONS

Pretreatment TLC and NLR may be useful for stratifying patients with ES-SCLC for treatment approaches.

The optimal treatment approaches for stage I small cell lung cancer

Although small cell lung cancer (SCLC) represents less than one-sixth of all lung cancer cases, it is an aggressive disease with a high metastatic potential to various sites including the brain. Most landmark trials assessing individual therapy benefits for SCLC dichotomized patients as having either limited or extensive disease. Over the last decade, however, there has been a clear shift towards categorizing and analyzing survival patterns using a more thorough staging system that accounts for tumor size and the degree of nodal or metastatic disease burden. For the 5% of patients who present with clinical stage I (cT1-2aN0M0) SCLC, extrapolating treatment recommendations from a rather heterogeneous population that constitutes limited disease SCLC remains controversial and has led to numerous investigations of alternative therapies such as stereotactic body radiation therapy (SBRT) for the management of this highly select group of patients. Given the changing landscape of multimodal therapy, this review will summarize relevant data pertaining to and outline optimal treatment algorithms for stage I SCLC, with a particular focus on SBRT as a primary mode of local therapy.

Current standards for clinical management of small cell lung cancer

Small cell lung cancer (SCLC) is an aggressive high-grade neuroendocrine carcinoma. Despite over 30 years of clinical research, little progress has been made in the management of SCLC, and outcomes remain poor. Here, we review the current clinical standards for management of SCLC and the data supporting these strategies.

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.

Carboplatin and Etoposide Followed by Once-Daily Thoracic Radiotherapy in Limited Disease Small-Cell Lung Cancer: Unsatisfactory Results

Aims and background

There has been a trend to replace cisplatin with carboplatin in the treatment of small-cell lung carcinoma. The goal of the present study was to determine the efficacy of carboplatin and etoposide followed by thoracic radiotherapy in patients with previously untreated limited disease small-cell lung carcinoma.

Methods

From February 2001 to March 2007, 47 patients with limited disease small-cell lung cancer were enrolled in the study. Etoposide, 100 mg/m2, was administrated intravenously on days 1-3 in combination with carboplatin, AUC 6, on day 1 every 21 days for 6 cycles. In cases considered to have non-progressive disease following induction chemotherapy, thoracic radiotherapy was given with in a once daily fraction of 2.0 Gy, 5/wk, up to 50-60 Gy.

Results

Forty-one patients were evaluated. Median age was 62 (range, 40-78), 88% of patients were male. ECOG PS was 0-1 in 38 patients. Seven of the 41 patients (17.5%) had pleural effusion (one malignant) and 7 patients (17.5%) had involved supraclavicular lymph nodes. Ninety percent of patients had elevated serum lactate dehydrogenase levels. Median follow-up was 13.5 mo. A total of 209 cycles of chemotherapy was administered (median, 6; range, 1-6). Thoracic irradiation was given to 33 patients. The overall response rate to combined modality on an intention-to-treat basis was 73%. Median survival time was 13.7 months (95% CI, 10.3-17.1), and median progression-free survival was 9.5 months (95% CI, 8.6-10.4). Two- and four-year overall survival was 23% and 7%, respectively. Grade 3-4 neutropenia and leukopenia were the most common adverse events and occurred in 46.0% and 24.0% of the patients, respectively. Six (14%) patients experienced febrile neutropenia. Three patients (7%) died of sepsis and neutropenic fever. Non-hematological toxicities were mild.

Conclusions

Carboplatin and etoposide chemotherapy followed by thoracic radiotherapy in LD-SCLC appears to be unsatisfactory.

The use of adaptive intensity-modulated radiotherapy in the treatment of small-cell carcinoma lung refractory to chemotherapy in a patient with preexisting interstitial lung disease

This is a case report of a 60-year-old diabetic, hypertensive male with a good performance status and a history of bilateral interstitial lung disease with a left upper lobe lung mass diagnosed to be a Stage IIB mixed small-cell/squamous cell carcinoma which was refractory to carboplatin- and etoposide-based chemotherapy. The patient was then taken up for adaptive intensity-modulated radiotherapy with tighter margin under image guidance with a mid-treatment replanning done at 25#. Acute toxicities were assessed weekly and showed no Grade 3 or more reactions. Pulmonary function test showed no detrimental changes during or after radiation. Response assessment at 12 and 20 weeks showed a partial response with decrease in metabolic activity on serial scans.

The role of radiation therapy in the management of small cell lung cancer

Small cell lung cancer (SCLC) is a very aggressive form of lung cancer. SCLC treatment requires multidisciplinary management and timely treatment. Radiation therapy is an important part of management of all stages of SCLC, in the curative as well as in the palliative setting. The role of radiation therapy in all stages of SCLC has changed in recent years; this article describes these changes and highlights the role of radiation therapy in the management of SCLC.

MicroRNA-related polymorphisms in apoptosis pathway genes are predictive of clinical outcome in patients with limited disease small cell lung cancer

We examined the impact of single nucleotide polymorphisms (SNPs) at miRNA binding sites in the 3'-UTRs of genes in the apoptosis pathway on the prognosis of patients with limited disease-small cell lung cancer (LD-SCLC). Twelve tagSNPs in seven genes were genotyped using blood samples from 146 LD-SCLC patients treated with chemoradiotherapy. Cox proportional hazard regression models and recursive partitioning analysis were performed to identify SNPs significantly associated with overall survival. Three SNPs, CASP8: rs1045494 (C > T), PIK3R1: rs3756668 (A > G) and CASP7: rs4353229 (T > C), were associated with longer overall survival in LD-SCLC patients after chemoradiotherapy. The adjusted hazard ratios (95% confidence intervals) were 0.480 (0.258-0.894), 0.405 (0.173-0.947) and 0.446 (0.247-0.802), respectively, and remained significant after multiple comparison correction. Moreover, subset analysis showed these SNPs were still predictive of overall survival in stage III patients. Recursive partitioning analysis enabled patients to be classified into three risk subgroups based on unfavorable genotype combinations of the rs1045494 and rs4353229 SNPs. These findings suggest miRNA-related polymorphisms in the apoptosis pathway may be useful biomarkers for selection of LD-SCLC patients likely to benefit from chemoradiotherapy.

Radiation Dose to the Thoracic Vertebral Bodies Is Associated With Acute Hematologic Toxicities in Patients Receiving Concurrent Chemoradiation for Lung Cancer: Results of a Single-Center Retrospective Analysis

PURPOSE

To test the hypothesis that increasing radiation therapy (RT) dose to the thoracic vertebral bodies (TVBs) contributes to the development of hematologic toxicities (HTs) in patients with lung cancer.

METHODS AND MATERIALS

Cases of non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) treated with definitive chemoradiation with concurrent platinum-based doublet chemotherapy at our institution from 2007 to 2016 were identified. Mean TVB dose and the volume of TVBs receiving at least 5 to 60 Gy (V₅-V₆₀) were retrospectively recorded. Logistic regression was used to test associations between grade ≥3 HT (HT3+) and dosimetric/clinical parameters. Normal tissue complication probability was evaluated using the Lyman-Kutcher-Burman (LKB) model for HT3+, and receiver operating characteristics analysis was used to determine dosimetric cut-points.

RESULTS

We identified 201 patients, the majority having NSCLC (n=162, 81%) and stage III to IV disease (n=179, 89%). All patients received either cisplatin/etoposide (n=107, 53%) or carboplatin/paclitaxel (n=94, 47%). Median RT dose was 60 Gy (range, 60-70 Gy). The rate of HT3+ was 49% (n=99). Increasing mean TVB dose (per Gy) was associated with higher odds of developing HT3+ (odds ratio 1.041, 95% confidence interval 1.004-1.080, P=.032), as were increasing TVB V₅ to V₂₀. These dosimetric correlates to HT3+ persisted on multivariate analysis. Constrained optimization of the LKB model for HT3+ yielded the parameters: n=1, m=1.79, and TD₅₀=21.4 Gy. Optimal cut-points identified were V₅=65%, V₁₀=60%, V₂₀=50%, and mean dose=23.5 Gy. Patients with values above these cut-points had an approximately 2-fold increased risk of HT3+.

CONCLUSIONS

We found that mean TVB dose and low-dose parameters (V₅-V₂₀) were associated with HT3+ in chemoradiation for lung cancer. Per the LKB model, bone marrow behaves like a parallel organ (n=1), implying that mean TVB dose is a useful predictor for toxicity. These data suggest that efforts to spare dose to the TVBs may reduce rates of severe HT.

Advances in targeting the transforming growth factor β1 signaling pathway in lung cancer radiotherapy

Lung cancer was demonstrated to be the most lethal type of malignant tumor amongst humans in the global cancer statistics of 2012. As one of the primary treatments, radiotherapy has been reported to induce remission in, and even cure, patients with lung cancer. However, the side effects of radiotherapy may prove lethal in certain patients. In past decades, the transforming growth factor β1 (TGFB1) signaling pathway has been revealed to serve multiple functions in the control of lung cancer progression and the radiotherapy response. In mammals, this signaling pathway is initiated through activation of the TGFB1 receptor complex, which signals via cytoplasmic SMAD proteins or other downstream signaling pathways. Multiple studies have demonstrated that TGFB1 serves important functions in lung cancer radiotherapy. The present study summarized and reviewed recent progress in elucidating the function of the TGFB1 signaling pathway in predicting radiation pneumonitis, as well as current strategies for targeting the TGFB1 signaling pathway in lung cancer radiotherapy, which may provide potential targets for lung cancer therapy.

Sites of recurrent disease and prognostic factors in SCLC patients treated with radiochemotherapy

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Most recurrences occurred within the primary tumor or initially affected lymph nodes.

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All sites of loco-regional recurrence had received 92–106% of the prescribed dose.

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No isolated nodal failure occurred, supporting the use of selective nodal irradiation.

Objectives

Concurrent radiochemotherapy (RCHT) is standard treatment in locally advanced small cell lung cancer (SCLC) patients. Due to conflicting results on elective nodal irradiation (ENI) or selective node irradiation (SNI) there is no clear evidence on optimal target volumes. Therefore, the purposes of this study were to assess the sites of recurrent disease in SCLC and to evaluate the feasibility of SNI versus ENI.

Methods

A retrospective single-institution study of 43 consecutive patients treated with RCHT was performed. After state-of-the-art staging including FDG-PET/CT, all patients underwent three-dimensional conformal radiotherapy to a total dose of 45 Gy in twice-daily fractions of 1.5 Gy starting concurrently with the first or second chemotherapy cycle. All sites of loco-regional recurrences were correlated to the initial tumor and dose delivered. The impact of potential prognostic variables on outcome was evaluated using the Cox-regression model.

Results

13 patients (30%) relapsed locally or regionally: six within the initial primary tumor volume, five within the initially affected lymph nodes, one metachronously within primary tumor and initially affected lymph nodes, and one both inside and outside of the initial nodal disease. All sites of loco-regional recurrence had received 92–106% of the prescribed dose.

Conclusion

In our study most recurrences occurred within the primary tumor or initially affected lymph nodes, or distantly. We did not register any case of isolated nodal failure, supporting the use of selective nodal irradiation, possibly with the addition of supraclavicular irradiation in patients with nodal disease in the upper mediastinum.

Patient selection for thoracic radiotherapy in extensive-stage small-cell lung cancer

Treatment of extensive-stage small-cell lung cancer remains a challenge with poor local control and overall survival. Chemotherapy is the mainstay of treatment, consisting of a combination of a platinum agent plus etoposide. The role of consolidative chest radiotherapy in extensive-stage small-cell lung cancer remains controversial. Two randomized clinical trials have been published demonstrating improved intrathoracic disease control with a small survival benefit, though interpretation and application of these results to clinical practice has been debated. These two trials examined different radiotherapy techniques and doses, with a third trial treating consolidative chest and oligometastatic disease having closed prematurely due to an interim analysis demonstrating treatment futility plus increased toxicity. Patients with residual intrathoracic disease after chemotherapy appear to benefit the most from consolidative chest radiotherapy, offering a potential tool to help select appropriate patients.

Receipt of thoracic radiation therapy and radiotherapy dose are correlated with outcomes in a retrospective study of three hundred and six patients with extensive stage small-cell lung cancer

BACKGROUND

The importance of the thoracic radiation therapy (TRT) dose has not been clearly defined in extensive stage small-cell lung cancer (ES-SCLC) and it is unclear whether improved TRT dose translates into a survival benefit.

METHODS

306 patients with ES-SCLC were retrospectively reviewed, of which 170 received IMRT/CRT fractionation RT after ChT, and 136 received chemotherapy (ChT) alone. We adopted the time-adjusted BED (tBED) for effective dose fractionation calculation. Due to the nonrandomized nature of this study, we compared the ChT+RT with ChT groups that matched on possible confounding variables.

RESULTS

Patients achieved 2-year OS, PFS and LC rates of 19.7%, 10.7% and 28.4%, respectively. After propensity score matching, (113 cases for each group), the rates of OS, PFS and LC at 2 years were 21.4%, 7.7% and 34.5% for ChT+TRT, and 10.3% (p<0.001), 4.6% (p<0.001) and 6.3% for ChT only (p<0.001), respectively. Among propensity score matching patients, 56 cases for each group received the high dose (tBED>50 Gy) TRT and received low dose (tBED≤50 Gy) TRT. Two-year OS, PFS and LC rates were 32.3%, 15.3% and 47.1% for the high dose compared with 17.0% (p<0.001), 12.9% (p=0.097) and 34.7% (p=0.029) for low dose radiotherapy.

CONCLUSIONS

TRT added to ChT improved ES-SCLC patient OS. High dose TRT improved OS over lower doses. Our results suggest that high-dose thoracic radiation therapy may be a reasonable consideration in select patients with ES-SCLC.

The Role of Advanced Imaging in Assessing Response to Definitive Chemoradiation Before Prophylactic Cranial Irradiation in Limited-Stage Small-Cell Lung Cancer

INTRODUCTION

Prophylactic cranial irradiation (PCI) improves survival for small-cell lung cancer (SCLC). Evidence for PCI in limited-stage SCLC largely derives from studies requiring only chest x-ray (CXR) to determine remission status. We analyzed thoracic chemoradiation therapy (TCRT) outcomes according to imaging modality to determine which patients benefitted most from PCI.

PATIENTS AND METHODS

All limited-stage SCLC patients who received TCRT as well as PCI at our institution were reviewed. Imaging between TCRT end and PCI start was characterized as complete (CR), partial (PR), or other response.

RESULTS

Thirty-eight consecutive patients were assessed for TCRT response before PCI with CXR (n = 21), chest computed tomography (CT; n = 27), and/or positron emission tomography (PET)/CT (n = 11). CR was identified on 71% of CXRs, 41% of CT scans, and 18% of PET/CT scans. Median survival was 28.3 months for the entire cohort and did not differ for patients who had CXR alone versus CT and/or PET/CT for restaging (P = .78) or those with PR using any modality versus CR using all modalities (22.6 months vs. 45.5 months; P = .22). CT CR patients had numerical but not statistically significant improved 2-year (P = .18) and 3-year (P = .13) survival compared with CT PR.

CONCLUSION

CXR remains an appropriate modality to assess TCRT response before PCI in limited-stage SCLC. Advanced imaging did not inform the decision to offer PCI in this study. Because of similar excellent survival profiles independent of imaging modality and TCRT response, this analysis suggests limited-stage SCLC patients with PR using any modality should not be denied PCI, akin to standards for extensive-stage SCLC.

Randomized Phase II Study Comparing Prophylactic Cranial Irradiation Alone to Prophylactic Cranial Irradiation and Consolidative Extracranial Irradiation for Extensive-Disease Small Cell Lung Cancer (ED SCLC): NRG Oncology RTOG 0937

INTRODUCTION

NRG Oncology RTOG 0937 is a randomized phase II trial evaluating 1-year overall survival (OS) with prophylactic cranial irradiation (PCI) or PCI plus consolidative radiation therapy (PCI+cRT) to intrathoracic disease and extracranial metastases for extensive-disease SCLC.

METHODS

Patients with one to four extracranial metastases were eligible after a complete response or partial response to chemotherapy. Randomization was to PCI or PCI+cRT to the thorax and metastases. Original stratification included partial response versus complete response after chemotherapy and one versus two to four metastases; age younger than 65 years versus 65 years or older was added after an observed imbalance. PCI consisted of 25 Gy in 10 fractions. cRT consisted of 45 Gy in 15 fractions. To detect an improvement in OS from 30% to 45% with a 34% hazard reduction (hazard ratio = 0.66) under a 0.1 type 1 error (one sided) and 80% power, 154 patients were required.

RESULTS

A total of 97 patients were randomized between March 2010 and February 2015. Eleven patients were ineligible (nine in the PCI group and two in the PCI+cRT group), leaving 42 randomized to receive PCI and 44 to receive PCI+cRT. At planned interim analysis, the study crossed the futility boundary for OS and was closed before meeting the accrual target. Median follow-up was 9 months. The 1-year OS was not different between the groups: 60.1% (95% confidence interval [CI]: 41.2-74.7) for PCI and 50.8% (95% CI: 34.0-65.3) for PCI+cRT (p = 0.21). The 3- and 12-month rates of progression were 53.3% and 79.6% for PCI and 14.5% and 75% for PCI+cRT, respectively. Time to progression favored PCI+cRT (hazard ratio = 0.53, 95% CI: 0.32-0.87, p = 0.01). One patient in each arm had grade 4 therapy-related toxicity and one had grade 5 therapy-related pneumonitis with PCI+cRT.

CONCLUSIONS

OS exceeded predictions for both arms. cRT delayed progression but did not improve 1-year OS.

Prophylactic Cranial Irradiation for Extensive-Stage Small-Cell Lung Cancer: A Retrospective Analysis

Purpose

Extensive-stage small-cell lung cancer (esSCLC) is an incurable disease and represents a therapeutic challenge because of its poor prognosis. Studies in prophylactic cranial irradiation (PCI) in esSCLC have shown a decreased incidence of symptomatic brain metastases in patients who respond to systemic chemotherapy. However, its effect on overall survival is debatable. We evaluated the benefit of PCI in patients with esSCLC in terms of overall survival, progression-free survival, incidence of brain metastases, recurrence rate, and exposure to postrecurrence therapies.

Materials and Methods

We retrospectively reviewed electronic charts from patients diagnosed with esSCLC from 2008 to 2014 at our institution. All patients had negative baseline brain imaging before chemotherapy and PCI and received at least 4 cycles of platinum-based chemotherapy in the first-line setting without progressive disease on follow-up. PCI was performed at the discretion of the treating physician. Analyses were based on descriptive statistics. Survival curves were calculated by Kaplan-Meier method.

Results

Among 46 eligible patients, 16 (35%) received PCI and 30 (65%) did not. Compared with no PCI, PCI led to improved progression-free survival (median, 10.32 v 7.66 months; hazard ratio, 0.4521; 95% CI, 0.2481 to 0.8237; P < .001) and overall survival (median, 20.94 v 11.05 months; hazard ratio, 0.2655; 95% CI, 0.1420 to 0.4964; P < .001) as well as lower incidence of brain metastases (19% v 53%; P = .0273) and higher exposure to second-line chemotherapy (87% v 57%; P = .0479).

Conclusion

Careful patient selection for PCI can improve not only brain metastases control and higher second-line chemotherapy exposure but also patient survival.

miR-300 regulates cellular radiosensitivity through targeting p53 and apaf1 in human lung cancer cells

microRNAs (miRNAs) play a crucial role in mediation of the cellular sensitivity to ionizing radiation (IR). Previous studies revealed that miR-300 was involved in the cellular response to IR or chemotherapy drug. However, whether miR-300 could regulate the DNA damage responses induced by extrinsic genotoxic stress in human lung cancer and the underlying mechanism remain unknown. In this study, the expression of miR-300 was examined in lung cancer cells treated with IR, and the effects of miR-300 on DNA damage repair, cell cycle arrest, apoptosis and senescence induced by IR were investigated. It was found that IR induced upregulation of endogenous miR-300, and ectopic expression of miR-300 by transfected with miR-300 mimics not only greatly enhanced the cellular DNA damage repair ability but also substantially abrogated the G2 cell cycle arrest and apoptosis induced by IR. Bioinformatic analysis predicted that p53 and apaf1 were potential targets of miR-300, and the luciferase reporter assay showed that miR-300 significantly suppressed the luciferase activity through binding to the 3'-UTR of p53 or apaf1 mRNA. In addition, overexpression of miR-300 significantly reduced p53/apaf1 and/or IR-induced p53/apaf1 protein expression levels. Flow cytomertry analysis and colony formation assay showed that miR-300 desensitized lung cancer cells to IR by suppressing p53-dependent G2 cell cycle arrest, apoptosis and senescence. These data demonstrate that miR-300 regulates the cellular sensitivity to IR through targeting p53 and apaf1 in lung cancer cells.

Cost-Effectiveness of Thoracic Radiation Therapy for Extensive-Stage Small Cell Lung Cancer Using Evidence From the Chest Radiotherapy Extensive-Stage Small Cell Lung Cancer Trial (CREST)

PURPOSE

The Chest Radiotherapy Extensive-Stage Small Cell Lung Cancer Trial (CREST) showed that adding thoracic radiation therapy (TRT) to the standard treatment (ST) paradigm of chemotherapy and prophylactic cranial irradiation improves overall survival and progression-free survival (PFS) in patients with extensive-stage small cell lung cancer (ES-SCLC). We evaluated the cost-effectiveness of adding TRT to ST in ES-SCLC patients.

METHODS AND MATERIALS

A cost-utility analysis was performed comparing TRT plus ST versus ST alone. The base-case time horizon was 24 months, consistent with the maximum PFS reported in the CREST. Overall survival was partitioned into 2 health states: PFS and postprogression survival. The proportion of patients in each health state over time was estimated by fitting parametric probability distributions to the CREST survival data. Costs were from a US health care payer perspective, and utilities were derived from the literature. Incremental cost-effectiveness ratios (ICERs) were calculated per quality-adjusted life-year (QALY) using a 3% discount rate. Sensitivity analyses addressed uncertainty in key variables.

RESULTS

In the base-case analysis, adding TRT to ST was both cost saving and more effective, thereby strongly dominating ST alone. At willingness-to-pay thresholds of $50,000/QALY, $100,000/QALY, and $200,000/QALY, TRT was preferred 68%, 81%, and 96% of the time, respectively. In the lifetime scenario analysis, the TRT ICER increased to $194,726/QALY.

CONCLUSIONS

By use of the actual follow-up interval reported in the CREST, adding TRT to ST strongly dominates a strategy of ST alone in ES-SCLC patients. Since the long-term survival benefit of TRT is small relative to ongoing costs of progressive metastatic disease, we estimate less favorable ICERs for TRT over a lifetime horizon.

Unravelling the biology of SCLC: implications for therapy

Small-cell lung cancer (SCLC) is an aggressive malignancy associated with a poor prognosis. First-line treatment has remained unchanged for decades, and a paucity of effective treatment options exists for recurrent disease. Nonetheless, advances in our understanding of SCLC biology have led to the development of novel experimental therapies. Poly [ADP-ribose] polymerase (PARP) inhibitors have shown promise in preclinical models, and are under clinical investigation in combination with cytotoxic therapies and inhibitors of cell-cycle checkpoints.Preclinical data indicate that targeting of histone-lysine N-methyltransferase EZH2, a regulator of chromatin remodelling implicated in acquired therapeutic resistance, might augment and prolong chemotherapy responses. High expression of the inhibitory Notch ligand Delta-like protein 3 (DLL3) in most SCLCs has been linked to expression of Achaete-scute homologue 1 (ASCL1; also known as ASH-1), a key transcription factor driving SCLC oncogenesis; encouraging preclinical and clinical activity has been demonstrated for an anti-DLL3-antibody-drug conjugate. The immune microenvironment of SCLC seems to be distinct from that of other solid tumours, with few tumour-infiltrating lymphocytes and low levels of the immune-checkpoint protein programmed cell death 1 ligand 1 (PD-L1). Nonetheless, immunotherapy with immune-checkpoint inhibitors holds promise for patients with this disease, independent of PD-L1 status. Herein, we review the progress made in uncovering aspects of the biology of SCLC and its microenvironment that are defining new therapeutic strategies and offering renewed hope for patients.

Treatment of limited disease small cell lung cancer: the multidisciplinary team

Small cell lung cancer (SCLC) presents multiple interdisciplinary challenges with several paradigm shifts in its treatment in recent years. SCLC treatment requires multidisciplinary management and timely treatment. The aim of this review is to focus on the team management aspects in the treatment of limited disease SCLC and how this can contribute towards improving outcomes.

Successful treatment of limited-stage small-cell lung cancer in the right mainstem bronchus by a combination of chemotherapy and argon plasma coagulation

The current standard-of-care treatment for patients with limited-stage small-cell lung cancer (SCLC) is concurrent chemoradiotherapy for local and systemic control. However, standard-of-care treatment strategies have not been established for those with limited-stage SCLC who have a history of thoracic radiotherapy due to concerns with complications associated with radiation overdose. A 37-year-old male developed an aspergilloma in the postoperative left thoracic space after he was treated with concurrent chemoradiotherapy for mediastinal type lung adenocarcionoma and subsequent left upper lobectomy for heterochronous dual adenocarcinoma. Fiberoptic bronchoscopy was performed to examine the status of the suspected bronchopleural fistula when a polypoid mass was observed in the right mainstem bronchus. A histological examination showed that the mass was SCLC at a clinical stage of cTisN0M0, stageIA, without local invasion. Since thoracic radiotherapy was not an option due to a previous history of thoracic irradiation, a combination treatment of carboplatin and etoposide was administered for 4 cycles and resulted in good partial response. In addition, argon plasma coagulation (APC) was performed as an alternative to curative radiotherapy on day 22 of the 4th cycle. The 5th cycle was administered 7 days after APC at which the anticancer therapy was completed. The patient remains disease-free 60 months after the completion of treatment, which suggests that this combination therapy may resolve very early-stage SCLC.