Twenty-five years of clinical research for patients with limited-stage small cell lung carcinoma in North America

Bi-weekly irinotecan is an effective and convenient regimen in the treatment of relapsed or refractory small cell lung cancer

BACKGROUND

Despite initial dramatic responses, metastatic small cell lung cancer (SCLC) invariably recurs. Irinotecan is one of the active agents for patients with recurrent SCLC. In the second line, weekly or three-weekly irinotecan regimens have been adopted, however, the optimal dose and schedule is not defined. In our institution, we use a bi-weekly regimen of irinotecan. In this study, we aimed to investigate the safety and efficacy of the bi-weekly irinotecan in the second- or third-line treatment of SCLC patients.

METHODS

The study population consisted of advanced stage SCLC patients who were followed at Hacettepe University Cancer Institute between January 2007 and March 2021 and received salvage irinotecan 180 mg/m2 every two weeks, following progression after platinum-etoposide treatment.

RESULTS

One hundred patients were included. At diagnosis, nineteen patients (19%) had limited stage and 81 patients (81%) had extensive stage SCLC. Objective response rates (ORR) were 44.6% and 46.2% for patients who received irinotecan treatment in second line, and in third line, respectively. Seventeen percent of all the patients had grade 3 and above adverse events during irinotecan treatment. In our study, 45.8% of patients were able to complete at least 6 cycles of irinotecan treatment and 69.8% were able to receive at least 3 cycles of irinotecan treatment without any dose interruption or reduction.

CONCLUSIONS

Irinotecan 180 mg/m2 every two weeks appears to be safe and effective in the 2nd- and 3rd-line treatment of advanced stage SCLC. Bi-weekly administration allows G-CSF prophylaxis in between doses, leading to an uninterrupted administration.

Recent advances in small cell lung cancer: the future is now?

Small cell lung cancer is a relevant clinical issue as it is a highly malignant cancer, often diagnosed in advanced stage. Similarly to non-small cell lung cancer, tobacco smoking is currently the main risk factor. Its incidence, at least in males, has declined over the past decades, due to the worldwide decreased percentage of active smokers. The typical small cells of this tumor type are characterized by a high Proliferation Index, chromosomal deletions such as 3p(14-23) involving the tumor-suppressor gene FHIT, alterations of the MYC or Notch family proteins and the frequent expression of neuroendocrine markers. The combination of thoracic radiotherapy and chemotherapy is the standard treatment for limited stage disease, while platinum-based chemotherapy is the most effective choice for extensive stage disease. Unfortunately, whatever chemotherapy is used, the results are disappointing. No regimen has proved to be effective in the long run, indeed small cell lung cancer rapidly progresses after a frequent initial strong response, and the mortality rate remains still high. The advent of immunotherapy is actually changing the landscape in oncology. As well as in other cancers, recent trials have demonstrated the efficacy of the combination of immune checkpoint inhibitors and chemotherapy, opening new perspectives for the future of our patients.

Synergistic Antitumor Effects of Anlotinib Combined with Oral 5-Fluorouracil/S-1 via Inhibiting Src/AKT Signaling Pathway in Small-Cell Lung Cancer

Background

Small-molecule tyrosine inhibitor anlotinib which developed in China has been approved as a third-line treatment for patients with small-cell lung cancer (SCLC). Our previous clinical study found that anlotinib combined with S-1 has better short-term ORR than the single-agent anlotinib of SCLC and other small-molecule vascular targeted drug therapies in the treatment of SCLC. However, the molecular mechanism of those effect remains unclear.

Methods

SCLC cell line H446 was treated with either anlotinib, 5-FU alone, or combination. The cellular effects including cell viability, cell apoptosis, cell cycle, cell migration, and invasion were explored to evaluate the cell proliferation level. Western blot was performed to determine the protein levels of the combined action of the two drugs. The xenograft mouse model was established by injection of H446 cells into mouse, and the animals were randomized and assigned for the drug treatments. Body weights and tumor sizes were recorded. WB was conducted using tumor tissues. All data were collected and statistically analyzed using t-test to reveal the underlying molecular mechanism.

Results

When anlotinib was combined with 5-FU, the IC50 value of cells was significantly reduced. And apoptosis, cell cycle arrest, and cell motility rates were stronger when anlotinib combined with 5-FU than in the anlotinib or 5-FU alone. In H446 cell-derived xenograft mouse model, tumor volumes were significantly decreased in Anlo/5-FU combination group than anlotinib or 5-FU alone group. Western blot showed the decreasing expression of p-Src/p-AKT in the Anlo/5-FU group.

Conclusion

Our data revealed that the treatment of combination of antitumor angiogenesis agent anlotinib with chemotherapy drug 5-FU may have synergistic cytotoxicity to SCLC in vitro and in vivo. This treatment modality reduced cell proliferation and migration via Src/AKT pathway. This new strategy may be a promising treatment for SCLC but needs to be confirmed in future clinical trials.

CCL19 associates with lymph node metastasis and inferior prognosis in patients with small cell lung cancer

OBJECTIVE

Small cell lung cancer (SCLC) is a systemic disease and most patients have metastases at diagnosis. Better understanding of the underlying mechanisms of SCLC metastasis may provide potential approach to improve clinical outcome.

METHODS

HTG Edge-seq was used to identify the differential gene expression between primary SCLC lesions and paired metastatic lymph nodes (LN). Overall survival (OS) analysis was performed in patients with different levels of plasma CCL19 concentration. Invasion, migration, proliferation, apoptosis and angiogenesis ability of SCLC cells and function of CD8 + T cells were evaluated in vitro to investigate the mechanism of CCL19 in promoting metastasis.

RESULTS

Four chemokines (CCL19, CCL21, CCL8, CCR1) were the most differentially expressed between primary lesions and metastatic LN. CCL19 was further investigated because its mRNA and protein level expression were also validated in four SCLC cell lines (H446, H69, H82, H196). Higher plasma CCL19 was associated with late lymph node (N3) metastasis (training cohort P = 0.044, validation cohort P = 0.020) and shorter OS (training cohort P = 0.040, validation cohort P = 0.047) in SCLC patients. Silencing CCL19 inhibited SCLC cell migration, invasion, proliferation and HUVECs tube formation. Furthermore, we found that CCL19 could decrease percentage of CD8 + Ki67 + and CD8 + GZMB + T cells and increase proportion of CD8 + PD1 + T cells.

CONCLUSION

CCL19 was associated with LN metastasis and poor prognosis in patients with SCLC. Its expression promoted tumor progression and metastasis and impaired the function of CD8 + T cells, suggesting CCL19 might be a potential target for SCLC.

Low level of complement factor H increases the risk of cancer-related death in patients with small-cell lung cancer

INTRODUCTION

Pulmonary cancer is a kind of deeply invasive tumour which is difficult to treat, and its mortality rate is high. Previous research has shown that activation of complement could contribute to the progression of non-small-cell lung cancer (SCLC). However, little research has been done on SCLC.

METHODS

Complement factor H (CFH), complements C3 as well as C4 were measured in patients, and the prognostic impact of different parameters was assessed by log-rank function analysis and Cox multifactor models. Besides, we constructed a predictive model based on complement fractions and validated the accuracy of the model.

RESULTS

Among these 242 patients, 200 (82.6%) died. The median survival time was 18.3 months. We found by multifactorial analysis that high levels of CFH decreased the risk of death (HR 0.23, 95% CI 0.10 to 0.57, p<0.001), while elevated complement C4 displayed poor prognosis (HR 2.28, 95% CI 1.66 to 3.13, p<0.001). We screened variables by Cox models and constructed CFH-based prediction models to plot a nomogram by internal validation. The nomogram showed excellent accuracy in assessing the probability of death, yielding an adjusted C-statistics of 0.905.

CONCLUSIONS

CFH can be recognised as a biomarker to predict the risk of death in SCLC. The prediction model established based on CFH, C3 and C4 levels has good accuracy in patients' prognostic assessment.

Longitudinal Assessment of Health Utility Scores, Symptoms and Toxicities in Patients with Small Cell Lung Cancer Using Real World Data

INTRODUCTION

Recent advances in small cell lung cancer (SCLC) treatments necessitate a better understanding of real-world health utility scores (HUS) in patients treated under current standards to facilitate robust pharmaco-economic assessments.

METHODS

In this single institution cohort observational study, HUS were evaluated in patients with SCLC through EQ-5D questionnaires at outpatient visits (encounters). In addition, patients completed questionnaires relating to treatment toxicities and cancer symptoms. Clinical and pathological variables were abstracted from electronic medical records and disease status at each patient visit was documented. The impact of these variables on HUS were explored.

RESULTS

There were 282 clinical encounters (12% newly diagnosed; 37% stable on treatment; 22% progressing on treatment; 29% stable off therapy/other) in 111 SCLC patients (58% male; 64% extensive stage (ES) SCLC). At the first encounter 29% of patients had an ECOG performance status (PS) ≥ 2. ES-SCLC, bone metastases, female sex, progressive disease and/or PS were each significantly associated with decreased HUS in multivariable analyses. Patients clinically stable on first line therapy had generally steady HUS longitudinally, with differences in HUS between limited disease (LD) and ES patients emerging as treatment progressed. Decreased HUS were associated with increased severity of the majority of measured symptoms (fatigue/tiredness, loss of appetite, pain, drowsiness, shortness of breath, anxiety, depression, and overall well-being; each p<0.001), supporting the value of EQ-5D-derived HUS in assessing health utility.

CONCLUSION

Our HUS values in chemotherapy-treated SCLC are clinically relevant and are associated with specific clinico-demographic, symptom and toxicity factors.

Is Small Cell Lung Cancer a Surgical Disease at the Present Time?

Small cell lung cancer is an aggressive form of cancer. Previously, surgery was rarely considered because most patients present at the advanced stages of the disease. New research and the advances in medical imaging has challenged this notion proving that, as part of a multimodal treatment pathway, surgery has a key role to play in the management of patients with early small cell lung cancer. In this chapter, we present the most pertinent research that has shaped clinical practice and outline the current treatment algorithm for small cell lung cancer.

Hippocampal avoidance in prophylactic cranial irradiation for small cell lung cancer: benefits and pitfalls

Small cell lung cancers (SCLC) are a group of cancers that are clinically and pathologically different from other lung cancers. They are associated with high recurrence rates and mortality, and many patients present with metastatic disease. Approximately ten percent of SCLC patients have brain metastases at time of diagnosis, and the cumulative incidence of brain metastases increases to more than fifty percent at two years, even with optimal treatment. Hence, in patients without brain metastases at presentation, prophylactic cranial irradiation (PCI) is an important component of treatment along with systemic chemotherapy and radiotherapy. The goal of PCI is to decrease the incidence of subsequent symptomatic brain metastases in patients who show an initial response to the systemic treatment. Various clinical trials have evaluated the utility of PCI and found substantial benefit. Unfortunately, the long-term toxicity associated with PCI, namely the neuro-cognitive impairment that may develop in patients as a result of the radiation toxicity to the hippocampal areas of the brain, has raised concern both for patients and their treating physicians. Various techniques have been tried to ameliorate the neuro-cognitive impairment associated with PCI, including pharmacological agents and highly conformal hippocampal avoidance radiation. All of these have shown promise, but there is a lack of clarity about the optimal way forward. Hippocampal avoidance PCI appears to be an excellent option and a number of groups are currently evaluating this technique. Although there is clear benefit with this specialized radiation treatment, there are also concerns about the risk of disease recurrence in the undertreated hippocampal areas. This review attempts to compile the available data regarding the benefits and pitfalls associated with hippocampal avoidance PCI in the setting of SCLC.

Harnessing the Immune System to Tackle Small Cell Lung Cancer

Immunotherapy has improved first-line therapy for small cell lung cancer and has activity in the relapsed setting as well. The immunobiology of small cell lung cancer poses challenges for immunotherapy, and efforts are underway to unlock to the potential of immunotherapy through the identification of meaningful disease subsets and the development of novel combination therapies.

Impact of subsequent chemotherapy on the survival of elderly patients with extensive stage small cell lung cancer

BACKGROUND/AIMS

The prognosis of small cell lung cancer (SCLC) is still poor because of rapid recurrence, despite good response to initial chemotherapy. Additionally, patients' old ages and comorbidities are often obstacles that make it difficult to apply subsequent treatment after initial treatment. This retrospective study analyzed the correlation of post-progression survival (PPS) with overall survival (OS), and prognostic factors including comorbidities to figure out impact of subsequent chemotherapy on OS in elderly extensive disease SCLC.

METHODS

We analyzed 101 patients of age 65 years or older who were recently diagnosed with extensive disease SCLC (ED-SCLC) in Korea University Medical Center between January 1995 and December 2015. The degree of comorbidity was scored using simplified comorbidity score (SCS). Correlation between PPS, progression-free survival (PFS) and OS was analyzed using a Pearson correlation coefficient. Cox proportional hazards regression was employed to examine the influence of clinical variables on survival.

RESULTS

Median age of patients was 71 years old (range, 65 to 83). Median OS was 8.7 months (range, 0.3 to 42.7). PPS was a reliable factor on OS than PFS (R2 = 0.852, p < 0.001). Prognostic factors associated with improved survival were SCS < 9, administration > 4 cycles of first line chemotherapy and subsequent second line chemotherapy.

CONCLUSION

PPS was more correlated with OS than PFS in elderly patients with ED-SCLC. The most important prognostic factors for PPS and OS included SCS and second line chemotherapy. Patients receiving subsequent treatment had increased OS regardless of degree of comorbidity.

Retrospective study of the incidence and outcomes from lung cancer in solid organ transplant recipients

OBJECTIVE

Organ transplant recipients (OTR) have an increased risk of developing post-transplant malignancies with lung cancer being one of the most common. In this retrospective study, we investigated incidence, use of systemic therapy and outcomes from lung cancer in OTR.

MATERIALS AND METHODS

Patients diagnosed with lung cancer following a solid organ transplant at the University Health Network, Toronto, ON, CA, from January 1, 1980 to June 30, 2016 were included. Data for the study population, patient characteristics, treatments and outcomes were abstracted from solid OTR databases, our cancer registry and patient charts. Univariate Kaplan-Meier curves estimated median overall survival (OS) by histology, stage and systemic therapy.

RESULTS

Amongst 7944 OTR (heart [N = 765], lung [n = 1668], liver [n = 2238], kidney [n = 3273]), 101 (1.3 %) developed lung cancer which were included in our analyses. Of these, 81 % were non-small cell lung cancer (NSCLC), 11 % small cell lung cancer (SCLC) and 8% neuroendocrine tumor (NET). Median OS (months) was 25 in those that presented with Stage I/II NSCLC (44 %); 25 for Stage III NSCLC (7%); 3 for Stage IV NCLC (31 %); 10 for Limited stage SCLC (6%); 2 for Extensive stage (ES) SCLC (5%). NSCLC patients that received palliative chemotherapy had an OS of 8 months; ES-SCLC patients that received chemotherapy had an OS of 6 months. Of all patients who received platinum doublets (n = 16), 10 (62.5 %) required dose reductions at some point. Five patients experienced febrile neutropenia (31 %); two (12 %) had other toxicities leading to discontinuation.

CONCLUSION

Patients with stage I/II NSCLC and NET had poorer survival compared to historical norms in non-transplant patients. Patients who had stage III NSCLC or received palliative systemic therapy had survivals at or slightly below historic norms, although numbers were small. Chemotherapy can be administered in selected OTR patients though dose reductions and febrile neutropenia were common.

A novel multi-target tyrosine kinase inhibitor anlotinib combined with irinotecan has in-vitro anti-tumor activity against human small-cell lung cancer

Anlotinib is a multi-target tyrosine kinase inhibitor developed independently in China. Its biological effects remain unclear in small-cell lung cancer (SCLC). The current study aimed to evaluate the effects of anlotinib in combination with irinotecan on H446 and H2227 SCLC cell lines and provide new treatment strategy for SCLC. Cell growth of two cell lines was inhibited by anlotinib, irinotecan and the combination in a dose-dependent manner. After 72 h incubation, the inhibition rate was greater in the combination group than all single drug group. A similar result was found when apoptosis was assessed after 12 h, but not after 6 h of treatment. Compared with single drug, combination drug suppressed the migration and invasion abilities in two cell lines; however, there was no difference between individual anlotinib or irinotecan. The colony formation rate was obviously lower in the combination group. Vascular endothelial growth factor receptor, fibroblast growth factor receptor (FGFR) and platelet-derived growth factor receptor were expressed in two cell lines after treatment regardless single or combination, but FGFR was expressed more after combination treatment than anlotinib. The expression of phosphorylated (p) ERK was decreased with anlotinib alone or combination treatment and pAKT expression was impaired with combination treatment, but not with anlotinib or irinotecan alone. The biological function of anlotinib and irinotecan may be mediated through the AKT/ERK signaling pathway. Additional investigations on biomarker-guided patient-stratification and elucidating individualized targets in patients anlotinib are urgently needed.

Update on the Biology, Management, and Treatment of Small Cell Lung Cancer (SCLC)

Small-cell lung cancer (SCLC) accounts for 13-15% of all new lung cancer cases in the US. The tumor has a tendency to disseminate early resulting in 80-85% of patients being diagnosed with extensive disease (ES-SCLC). Chemotherapy has provided SCLC patients considerable survival benefits over the past three decades. Nonetheless, most patients relapse and rarely survive beyond 2 years. Despite consistent overall response rates of ≥50%, until recently, median survival times and 2-year survivals only ranged between 7-10 months and 10-20%, respectively. Several chemotherapy agents possess activity against SCLC, both, as single agents and in combinations but etoposide-platinum emerged as the preferred first line regimen. Upon relapse, many patients remain candidates for additional therapy. However, the sensitivity of relapsed SCLC to further therapies is markedly reduced and dependent upon the level and duration of response to the initial treatment (platinum-sensitive vs. resistant relapse). Multiple factors suggest a therapeutic role for immunotherapy in SCLC: SCLC has been associated with immune-mediated paraneoplastic processes (cerebellar degeneration, limbic encephalitis, and Lambert-Eaton syndrome) and patients presenting with these paraneoplastic syndromes have shown more favorable outcomes, suggesting an underlying immune response mechanism.Comprehensive genomic profiling of SCLC indicates that the majority lack functional p53 (90%) and Rb1 (65%). These universal genetic aberrations facilitate poor genomic stability, thus perpetuating the generation of tumor associated antigens, amenable to targeting with immunotherapy.SCLC has one of the highest mutational loads, likely a reflection of the myriad of insults inflicted by smoking-related carcinogens. The relationship between tumor mutational load and response to immune checkpoint inhibitors has been established in multiple solid tumors, including preliminary results in relapsed SCLC. In this manuscript, we review the early (some failed and discontinued, some partly successful, and still ongoing) attempts to incorporate immunotherapy (particularly vaccine based approaches) to the treatment of SCLC, and the latest attempts (mostly incorporating the use of checkpoint inhibitors), including those with favorable but preliminary results (CheckMate 032, Keynote 028 and 158), and those with more definitive positive (iMpower 133 and CASPIAN) and negative (CheckMate 331 and 451) results.

The impact of quantitative CT-based tumor volumetric features on the outcomes of patients with limited stage small cell lung cancer

INTRODUCTION

Limited stage small cell lung cancer (LS-SCLC) has a poor prognosis. Additional prognostic markers are needed for risk-stratification and treatment intensification. This study compares quantitative CT-based volumetric tumor measurements versus International Association for the Study of Lung Cancer (IASLC) TNM staging to predict outcomes.

MATERIALS & METHODS

A cohort of 105 patients diagnosed with LS-SCLC and treated with chemoradiation (CRT) from 2000 to 2013 were analyzed retrospectively. Patients were staged by the Union for International Cancer Control (UICC) TNM Classification, 8th edition. Tumor volumes and diameters were extracted from radiation planning CT imaging. Univariable and multivariable models were used to analyze relationships between CT features and overall survival (OS), locoregional recurrence (LRR), in-field LRR, any progression, and distant metastasis (DM).

RESULTS

Median follow-up was 21.3 months. Two-year outcomes were as follows: 38% LRR, 31% in-field LRR, 52% DM, 62% any progression, and 47% OS (median survival 16.5 months). On univariable analysis, UICC T-stage and N-stage were not associated with any clinical outcome. UICC overall stage was only statistically associated with in-field LRR. One imaging feature (3D maximum tumor diameter) was found to be significantly associated with LRR (HR 1.10, p = 0.003), in-field LRR (HR 1.10, p = 0.007), DM (HR 1.10, p = 0.02), any progression (HR 1.10, p = 0.008), and OS (HR 1.10, p = 0.03). On multivariable analysis, this feature remained significantly associated with all outcomes.

CONCLUSION

For LS-SCLC, quantitative CT-based volumetric tumor measurements were significantly associated with outcomes after CRT and may be better predictors of outcome than TNM stage.

Radiotherapy Planning and Molecular Imaging in Lung Cancer

INTRODUCTION

In patients suitable for radical chemoradiotherapy for lung cancer, 18F-FDGPET/ CT is a proposed management to improve the accuracy of high dose radiotherapy. However, there is a high rate of locoregional failure in patients with locally advanced non-small cell lung cancer (NSCLC), probably due to the fact that standard dosing may not be effective in all patients. The aim of the present review was to address some criticisms associated with the radiotherapy image-guided in NSCLC.

MATERIALS AND METHODS

A systematic literature search was conducted. Only published articles that met the following criteria were included: articles, only original papers, radiopharmaceutical ([18F]FDG and any tracer other than [18F]FDG), target, only specific for lung cancer radiotherapy planning, and experimental design (eventually "in vitro" studies were excluded). Peer-reviewed indexed journals, regardless of publication status (published, ahead of print, in press, etc.) were included. Reviews, case reports, abstracts, editorials, poster presentations, and publications in languages other than English were excluded. The decision to include or exclude an article was made by consensus and any disagreement was resolved through discussion.

RESULTS

Hundred eligible full-text articles were assessed. Diverse information is now available in the literature about the role of FDG and new alternative radiopharmaceuticals for the planning of radiotherapy in NSCLC. In particular, the role of alternative technologies for the segmentation of FDG uptake is essential, although indeterminate for RT planning. The pros and cons of the available techniques have been extensively reported.

CONCLUSION

PET/CT has a central place in the planning of radiotherapy for lung cancer and, in particular, for NSCLC assuming a substantial role in the delineation of tumor volume. The development of new radiopharmaceuticals can help overcome the problems related to the disadvantage of FDG to accumulate also in activated inflammatory cells, thus improving tumor characterization and providing new prognostic biomarkers.

Role of prophylactic cranial irradiation for elderly patients with limited-disease small-cell lung cancer: inverse probability of treatment weighting using propensity score

Studies of prophylactic cranial irradiation (PCI) focused on elderly patients with small-cell lung cancer (SCLC) are rarely conducted. We aimed to identify whether there is a survival benefit of prophylactic cranial irradiation (PCI) in elderly patients using a single institution's retrospective data. A total of 234 patients with limited-disease SCLC (LD-SCLC) treated with thoracic chemoradiotherapy were evaluated; of these, 139 patients received PCI. To minimize treatment selection bias, patients were adjusted using the propensity score on factors associated with receipt of PCI. Cox proportional hazard model and Kaplan-Meier analyses were used to identify which subgroup may benefit from PCI. Median follow-up time was 22 months (range 1-150 months). PCI was associated with favorable brain metastasis-free survival, disease-specific survival, and overall survival in the entire population [hazard ratios (HR) 0.588, 95% confidence interval (CI) 0.338-1.024, P = 0.060; HR 0.477, 95% CI 0.331-0.687, P < 0.001; HR 0.543, 95% CI 0.383-0.771, P = 0.001, respectively). However, PCI had no significant relationship with overall survival in patients aged ≥65 years with cT3-4 disease and/or females gender (HR 0.817, 95% CI 0.098-6.849, P = 0.853; HR 1.082, 95% CI 0.114-10.227, P = 0.946, respectively). The benefits and risks of PCI in elderly patients with LD-SCLC need to be scrutinized, especially in those with high T stage tumors and/or females.

Anti-Tumor Effects of Low Dose Zoledronate on Lung Cancer-Induced Spine Metastasis

Zoledronate (Zol) is an anti-resorptive/tumoral agent used for the treatment of many cancers including spinal bone metastasis. High systemic administration of a single dose is now the standard clinical care, yet it has been associated with several side effects. Here, we aimed to evaluate the effects of lower doses Zol on lung cancer and lung cancer-induced bone metastasis cells over a longer time period. Human lung cancer (HCC827) and three bone metastases secondary to lung cancer (BML1, BML3 and BML4) cells were treated with Zol at 1, 3 and 10 µM for 7 days and then assessed for cell proliferation, migration, invasion and apoptosis. Low Zol treatment significantly decreased cell proliferation (1, 3 and 10 µM), migration (3 and 10 µM) and invasion (10 µM) while increasing apoptosis (10 µM) in lung cancer and metastatic cells. Our data exploits the potential of using low doses Zol for longer treatment periods and reinforces this approach as a new therapeutic regimen to impede the development of metastatic bone cancer while limiting severe side effects following high doses of systemic drug treatment.

Choice of surgical procedure - lobectomy, segmentectomy, or wedge resection - for patients with stage T1-2N0M0 small cell lung cancer: A population-based study

Background

To date, few studies have evaluated the impact of lobectomy versus sublobar resection for early small cell lung cancer (SCLC). We investigated the survival rates of patients with pathological stage T1‐2N0M0 SCLC who underwent lobectomy or sublobar resection.

Methods

We identified 548 SCLC patients in the Surveillance, Epidemiology, and End Results database who underwent lobectomy or sublobar resection. Propensity score matching (PSM) and Cox regression analysis were used to adjust for baseline characteristics.

Results

The three‐year overall survival (OS) of patients treated with lobectomy (n = 376, 60%) was significantly higher than those treated with sublobar resection (n = 172, 38%). PSM and Cox multivariable analysis further confirmed this result (hazard ratio [HR] 0.543, 95% confidence interval [CI] 0.421–0.680; P < 0.001). The three‐year OS of patients treated with segmentectomy (n = 24, 54%) and wedge resection (n = 148, 36%) was not significantly different (HR 0.639, 95% CI 0.393–1.039; P = 0.071). Based on PSM analysis, segmentectomy conferred a superior survival advantage to patients relative to wedge resection (HR 0.466, 95% CI 0.221–0.979; P = 0.040).

Conclusion

Lobectomy correlated with superior survival. For patients in which lobectomy is unsuitable, prognosis following segmentectomy appears to be better than after wedge resection.

Cullin5 deficiency promotes small-cell lung cancer metastasis by stabilizing integrin β1

Metastasis is the dominant cause of patient death in small-cell lung cancer (SCLC), and a better understanding of the molecular mechanisms underlying SCLC metastasis may potentially improve clinical treatment. Through genome-scale screening for key regulators of mouse Rb1-/- Trp53-/- SCLC metastasis using the pooled CRISPR/Cas9 library, we identified Cullin5 (CUL5) and suppressor of cytokine signaling 3 (SOCS3), two components of the Cullin-RING E3 ubiquitin ligase complex, as top candidates. Mechanistically, the deficiency of CUL5 or SOCS3 disrupted the functional formation of the E3 ligase complex and prevented the degradation of integrin β1, which stabilized integrin β1 and activated downstream focal adhesion kinase/SRC (FAK/SRC) signaling and eventually drove SCLC metastasis. Low expression levels of CUL5 and SOCS3 were significantly associated with high integrin β1 levels and poor prognosis in a large cohort of 128 clinical patients with SCLC. Moreover, the CUL5-deficient SCLCs were vulnerable to the treatment of the FDA-approved SRC inhibitor dasatinib. Collectively, this work identifies the essential role of CUL5- and SOCS3-mediated integrin β1 turnover in controlling SCLC metastasis, which might have therapeutic implications.

Immune Checkpoint Inhibitors in the Management of Lung Cancer

Immune checkpoint inhibitors, specifically PD-1-directed agents, have changed the treatment paradigm of non-small cell lung cancer (NSCLC) and are being actively evaluated in patients with small cell lung cancer. After initial studies demonstrated survival advantage with these agents in patients with recurrent NSCLC, these agents now have demonstrated survival advantage in some patients with early-stage NSCLC. Further evaluation of these agents in combination with chemotherapy regimens and other checkpoint inhibitors is ongoing. Recent data suggest that addition of these agents to chemotherapy may improve survival compared with chemotherapy alone. Promising results have also been observed in patients with recurrent small cell lung cancer. Ongoing studies will define the role of these agents in the management of patients with small cell lung cancer. Tumor PD-L1 assessment has become standard of care since use of frontline pembrolizumab in patients with advanced NSCLC is based on tumor PD-L1 expression. Other biomarkers are being actively evaluated to identify the patients most likely to benefit from these agents. Unique adverse effects are observed with the use of immune checkpoint inhibitors. Knowledge of the adverse effects and their management is crucial in treating patients with lung cancer using immune checkpoint inhibitors.

Circulating endothelial cells and microparticles as diagnostic and prognostic biomarkers in small-cell lung cancer

OBJECTIVES

It has been proposed that circulating endothelial cells (CECs) and microparticles (MPs) may be useful for the assessment of patients with non-small-cell lung cancer (NSCLC). However, little is known about the potential clinical relevance of these biomarkers in small-cell lung cancer (SCLC). Therefore, we investigated the utility of baseline levels of CECs and MPs in SCLC patients.

MATERIALS AND METHODS

An immunomagnetic separation (IMS) technique was used to isolate and quantify CECs in the peripheral blood, while plasma samples were analyzed using flow cytometry for the measurement of circulating MPs.

RESULTS

We prospectively collected data from 56 patients and 41 healthy individuals. Forty-three patients presented at initial diagnosis and 13 patients presented at relapse. Baseline levels of CECs and MPs were significantly higher in SCLC patients either at initial diagnosis or at relapse than in healthy subjects (p < 0.0002 and p < 0.007, respectively). However, estimated tumor volume (ETV) was significantly correlated with basal MP values (p < 0.0001) but not with pretreatment CECs (p =  0.57). The amount of baseline CECs and MPs was significantly lower in patients with an objective response (OR, n = 23) than in those with progressive disease (PD, n = 15) after treatment (p =  0.016 and 0.05, respectively). With cut-off values of 110 cells/mL for CECs and 1257 events/μL for MPs according to receiver operating characteristics (ROC) analysis, baseline levels of these biomarkers were not significantly correlated with either progression-free survival (PFS) or overall survival (OS). However, patients with 6-month PFS displayed significantly decreased pretreatment CEC counts (p =  0.042), whereas basal MP values significantly increased in 1-year survivors compared with those in non-survivors (p =  0.05).

CONCLUSION

Our results suggest that baseline CECs and MPs may be predictive biomarkers of tumor response and long-term survival in SCLC patients.

Immune checkpoint inhibitors in small cell lung cancer

Small cell lung cancer (SCLC) is a rapidly progressive cancer that often debilitates patients within months of detection and quickly becomes refractory to the limited options of therapy. While SCLC is not generally considered an immunogenic tumor, clinical experience suggests that patients with robust immune response manifesting as paraneoplastic syndrome are more likely to present with limited stage of the disease and tend to have a better prognosis. Monoclonal antibodies targeting critical negative regulators of immune response, so called immune checkpoints, such as cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed death 1 (PD-1) have expanded the application of immune-based therapies to increasing number of advanced stage cancers. These agents overcome the inhibitory immune signals leading to a heightened immune response against cancer cells. These immune checkpoint inhibitors have established efficacy leading to regulatory approval for their use in many cancer types including non-small cell lung cancer (NSCLC). Evaluation of the CTLA-4 inhibitor, ipilimumab and PD-1 inhibitors, nivolumab and pembrolizumab in SCLC have shown encouraging signal but definitive studies are still ongoing. In this review, we discuss the rationale behind the use of checkpoint inhibitors in SCLC, contextualize the results of early trials of immunotherapy agents in SCLC and project the future evolution of this strategy.

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.

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

•

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.

The revision of 8th edition TNM stage criteria is more accurate in prediction postoperative survival for SCLC patients

OBJECTIVES

The 8th edition TNM lung cancer classification was enacted in January 2017. An important change is the old T2a was revised to new T2a and T2b. Whether a postoperative survival difference exists between the two stages is still undefined. The purpose of this study is to investigate the postoperative outcomes of small cell lung cancer (SCLC) patients and compare the survival difference between the two stages.

METHODS

Data of patients with SCLC who underwent surgery between October 2005 and August 2013 at our institute were reviewed. A total number of 194 patients were enrolled and were reclassified according to the 8th edition TNM stage. Survival was determined by Kaplan-Meier analysis, the log-rank test was used to compare survival differences.

RESULTS

Surgical resection included 165 lobectomy or bilobectomy, 19 sublobectomy and 10 pneumonectomy. There were 159 patients received chemotherapy, 35 underwent surgery alone. The 5-year survival rate and median survival time (MST) of whole group was 34.5% and 45 months. For patients who received similar therapy (surgery plus chemotherapy) in N0 stage, the MST of T2a stage was 83 months, significantly longer than 62 months in T2b stage (P = 0.017).

CONCLUSIONS

In the 8th edition TNM lung cancer stage criteria, the postoperative survival of T2a is superior to T2b for non-metastatic SCLC at N0 stage.

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.

Changing epidemiology of elderly small cell lung cancer patients over the last 40 years; a SEER database analysis

BACKGROUND

Small cell lung cancer (SCLC) is a distinct clinical and pathological entity within the spectrum of lung cancer. It was observed that the relative age distribution of the disease changed over years.

METHODS

Surveillance, epidemiology, and end results (SEER) database (1973-2013) was utilized to determine the incidence, presentation and treatment outcomes of elderly patients (>70 years) with SCLC. Join point regression analysis was then conducted to analyze age-adjusted trends in incidence for the elderly as well as the whole SCLC population. Survival analysis was conducted through Kaplan-Meier analysis. Clinicopathological characteristics and survival outcomes were compared between patients diagnosed at 70-79 years old and those older than 80 years old (octogenarian group).

RESULTS

The proportion of elderly patients among all cases of SCLC increased from 23% in 1975 to 44% in 2010. Moreover, the proportion of elderly female patients among all cases of elderly SCLC increased from 25% in 1975 to 49% in 2010. When categorizing patients into four subgroups "70-74," "75-79," "80-84," and "85+", there was a trend toward a lower cancer-specific survival with increasing age (P < .0001). A limited improvement in 5 year survival was observed during the study period and it is less apparent as the age increases.

CONCLUSION

The proportion of elderly patients among all cases of SCLC has increased over the past 40 years. Further studies are needed to better select appropriate treatments for this subset of patients.

Nomogram prediction for the survival of the patients with small cell lung cancer

BACKGROUND

Small cell lung cancer (SCLC) is a subtype of lung cancer with poor prognosis. In this study, we aimed to build a nomogram to predict the survival of individual with SCLC by incorporating significant clinical parameters.

METHODS

The patients with SCLC were enrolled from the First Affiliated Hospital of Guangzhou Medical University (GMUFAH) between 2009 and 2013. We identified and incorporated the independent prognostic factors to build a nomogram to predict the survival of SCLC patients. The predictive accuracy and discriminative ability of the nomogram were evaluated by concordance index (C-index) and calibration curve. We also compared the accuracy of the built model with the 7^th AJCC TNM and VALSG staging system. The nomogram was further validated in an independent cohort of 80 patients with SCLC from Cancer Center of Guangzhou Medical University (GMUCC) between 2009 and 2013.

RESULTS

A total of 275 patients with SCLC were included in the primary cohort, and seven independent prognostic factors were identified including age, N stage, metastasis status, histology, platelets to lymphocyte ratio (PLR), neuron specific enolase (NSE) and CYFRA21-1 as independent prognostic factors after using Cox regression model. A nomogram incorporating these prognostic factors was subsequently built. The calibration curves for possibilities of 1-, 2-year overall survival (OS) revealed optimal agreement between nomogram prediction and actual observation. The C-index of this nomogram was higher than that of TNM and VALSG staging system in both primary and validation cohort (nomogram vs. TNM, primary cohort 0.68 vs. 0.65, P<0.01, validation cohort 0.66 vs. 0.62, P<0.05; nomogram vs. VALSG, primary cohort 0.68 vs. 0.66, P<0.01, validation cohort 0.66 vs. 0.64, P<0.05).

CONCLUSIONS

In this study, we established and validated a novel nomogram for the prediction of OS for the patients with SCLC. This model could provide more accurate individual prediction of survival probability of SCLC than the existing staging systems.

Vasculogenic mimicry in small cell lung cancer

Small cell lung cancer (SCLC) is characterized by prevalent circulating tumour cells (CTCs), early metastasis and poor prognosis. We show that SCLC patients (37/38) have rare CTC subpopulations co-expressing vascular endothelial-cadherin (VE-cadherin) and cytokeratins consistent with vasculogenic mimicry (VM), a process whereby tumour cells form 'endothelial-like' vessels. Single-cell genomic analysis reveals characteristic SCLC genomic changes in both VE-cadherin-positive and -negative CTCs. Higher levels of VM are associated with worse overall survival in 41 limited-stage patients' biopsies (P<0.025). VM vessels are also observed in 9/10 CTC patient-derived explants (CDX), where molecular analysis of fractionated VE-cadherin-positive cells uncovered copy-number alterations and mutated TP53, confirming human tumour origin. VE-cadherin is required for VM in NCI-H446 SCLC xenografts, where VM decreases tumour latency and, despite increased cisplatin intra-tumour delivery, decreases cisplatin efficacy. The functional significance of VM in SCLC suggests VM regulation may provide new targets for therapeutic intervention.

Percutaneous Thermal Ablation for Small-Cell Lung Cancer: Initial Experience with Ten Tumors in Nine Patients

PURPOSE

To evaluate outcomes in a small cohort of patients with local or disseminated small-cell lung cancer (SCLC) who received percutaneous thermal ablation therapy.

MATERIALS AND METHODS

Ten biopsy-proven SCLC tumors in 9 consecutive patients (5 men, 4 women; average age, 73.8 y ± 12.4) were retrospectively evaluated. Average tumor sizes were 1.8 cm ± 0.5 and 2.6 cm ± 1.2 among patients with local and disseminated disease, respectively. Microwave and radiofrequency ablation were each used for 5 tumors. None of the patients with local SCLC received adjuvant therapy following thermal ablation. Median follow-up duration was 16 months (range, 2-48 mo). Median and 1-year overall survival (OS) were compared for patients in the local and disseminated disease groups.

RESULTS

Median and 1-year OS were better among patients treated for local SCLC compared with disseminated disease (47.0 vs 5.5 mo and 3 [100%] vs 2 [40%], respectively). Pneumothorax occurred in 5 patients (55.6%), and 3 patients received successful outpatient thoracostomy tube placement. No patients were hospitalized, and there were no major complications.

CONCLUSIONS

This preliminary analysis suggests favorable outcomes in selected patients with local SCLC who undergo percutaneous thermal ablation without adjuvant therapy.

Consolidation chemotherapy improves progression-free survival in stage III small-cell lung cancer following concurrent chemoradiotherapy: a retrospective study

BACKGROUND

Concurrent chemoradiotherapy (CCRT) is the standard treatment for limited-stage small-cell lung cancer (LD-SCLC). However, the efficacy of consolidation chemotherapy (CCT) in LD-SCLC remains controversial despite several studies that were performed in the early years of CCT use. The aim of this study was to reevaluate the effectiveness and toxicities associated with CCT.

METHODS

This retrospective analysis evaluated 177 patients with stage IIIA and IIIB small-cell lung cancer (SCLC) who underwent CCRT from January 2001 to December 2013 at Sun Yat-Sen University Cancer Center (SYSUCC). Overall survival (OS) and progression-free survival (PFS) were analyzed using Kaplan-Meier methods. Univariate and multivariate analyses were performed to analyze patient prognosis factors.

RESULTS

Among the 177 patients, 72 (41%) received CCT and 105 (59%) did not receive CCT. PFS was significantly better for patients in the CCT group compared to that for patients in the non-CCT group (median PFS: 17.0 vs 12.9 months, respectively, P=0.031), whereas the differences in OS were not statistically significant (median OS: 31.6 vs 24.8 months, respectively, P=0.118). The 3- and 5-year OS rates were 33.3% and 20.8% for patients in the CCT group and 27.6% and 6.7% for patients in the non-CCT group, respectively. Multivariate analysis revealed that having a pretreatment carcinoembryonic antigen level <5 ng/mL (P=0.035), having undergone prophylactic cranial irradiation (P<0.001), and having received CCT (P=0.002) could serve as favorable independent prognostic factors for PFS. Multivariate analysis for OS also showed that having undergone PCI (P<0.001) and having received CCT (P=0.006) were independent significant prognostic factors.

CONCLUSION

CCT can improve PFS for patients with stage IIIA and IIIB SCLC following CCRT without significantly increasing treatment-related toxicities.

Cancer Stem Cells in Small Cell Lung Cancer Cell Line H446: Higher Dependency on Oxidative Phosphorylation and Mitochondrial Substrate-Level Phosphorylation than Non-Stem Cancer Cells

Recently, targeting cancer stem cells (CSCs) metabolism is becoming a promising therapeutic approach to improve cancer treatment outcomes. However, knowledge of the metabolic state of CSCs in small cell lung cancer is still lacking. In this study, we found that CSCs had significantly lower oxygen consumption rate and extracellular acidification rate than non-stem cancer cells. Meanwhile, this subpopulation of cells consumed less glucose, produced less lactate and maintained lower ATP levels. We also revealed that CSCs could produce more ATP through mitochondrial substrate-level phosphorylation during respiratory inhibition compared with non-stem cancer cells. Furthermore, they were more sensitive to suppression of oxidative phosphorylation. Therefore, oligomycin (inhibitor of oxidative phosphorylation) could severely impair sphere-forming and tumor-initiating abilities of CSCs. Our work suggests that CSCs represent metabolically inactive tumor subpopulations which sustain in a state showing low metabolic activity. However, mitochondrial substrate-level phosphorylation of CSCs may be more active than that of non-stem cancer cells. Moreover, CSCs showed preferential use of oxidative phosphorylation over glycolysis to meet their energy demand. These results extend our understanding of CSCs metabolism, potentially providing novel treatment strategies targeting metabolic pathways in small cell lung cancer.

The spectrum of neuroendocrine tumors: histologic classification, unique features and areas of overlap

Neuroendocrine neoplasms are diverse in terms of sites of origin, functional status, and degrees of aggressiveness. This review will introduce some of the common features of neuroendocrine neoplasms and will explore the differences in pathology, classification, biology, and clinical management between tumors of different anatomic sites, specifically, the lung, pancreas, and prostate. Despite sharing neuroendocrine differentiation and histologic evidence of the neuroendocrine phenotype in most organs, well-differentiated neuroendocrine tumors (WD-NETs) and poorly differentiated neuroendocrine carcinomas (PD-NECs) are two very different families of neoplasms. WD-NETs (grade 1 and 2) are relatively indolent (with a natural history that can evolve over many years or decades), closely resemble non-neoplastic neuroendocrine cells, and demonstrate production of neurosecretory proteins, such as chromogranin A. They arise in the lungs and throughout the gastrointestinal tract and pancreas, but WD-NETs of the prostate gland are uncommon. Surgical resection is the mainstay of therapy, but treatment of unresectable disease depends on the site of origin. In contrast, PD-NECs (grade 3, small cell or large cell) of all sites often demonstrate alterations in P53 and Rb, exhibit an aggressive clinical course, and are treated with platinum-based chemotherapy. Only WD-NETs arise in patients with inherited neuroendocrine neoplasia syndromes (e.g., multiple endocrine neoplasia type 1), and some common genetic alterations are site-specific (e.g., TMPRSS2-ERG gene rearrangement in PD-NECs arising in the prostate gland). Advances in our understanding of the molecular basis of NETs should lead to new diagnostic and therapeutic strategies and is an area of active investigation.

Small cell lung cancer (SCLC): no treatment advances in recent years

Small cell lung cancer (SCLC) is an aggressive malignancy with a distinct natural history and dismal prognosis. Given its predisposition for early dissemination, patients are commonly diagnosed with metastatic disease and chemotherapy is regarded as the cornerstone of approved treatment strategies. However, over the last 30 years there has been a distinct paucity of significant breakthroughs in SCLC therapy. Thus, SCLC is characterized as a recalcitrant neoplasm with limited therapeutic options. By employing well-established research approaches, proven to be efficacious in non-small cell lung cancer (NSCLC), a growing amount of data has shed light on the molecular biology of SCLC and enhanced our knowledge of the "drivers" of tumor cell survival and proliferation. New therapeutic targets have emerged, but no significant improvement in patients' survival has been demonstrated thus far. In a sense, the more we know, the more we fail. Nowadays this is starting to change and methodical research efforts are underway. It is anticipated that the next decade will see a revolution in the treatment of SCLC patients with the application of effective precision medicine and immunotherapy strategies.

Lung cancer: Biology and treatment options

Lung cancer remains the leading cause of cancer mortality in men and women in the U.S. and worldwide. About 90% of lung cancer cases are caused by smoking and the use of tobacco products. However, other factors such as radon gas, asbestos, air pollution exposures, and chronic infections can contribute to lung carcinogenesis. In addition, multiple inherited and acquired mechanisms of susceptibility to lung cancer have been proposed. Lung cancer is divided into two broad histologic classes, which grow and spread differently: small-cell lung carcinomas (SCLCs) and non-small cell lung carcinomas (NSCLCs). Treatment options for lung cancer include surgery, radiation therapy, chemotherapy, and targeted therapy. Therapeutic-modalities recommendations depend on several factors, including the type and stage of cancer. Despite the improvements in diagnosis and therapy made during the past 25 years, the prognosis for patients with lung cancer is still unsatisfactory. The responses to current standard therapies are poor except for the most localized cancers. However, a better understanding of the biology pertinent to these challenging malignancies, might lead to the development of more efficacious and perhaps more specific drugs. The purpose of this review is to summarize the recent developments in lung cancer biology and its therapeutic strategies, and discuss the latest treatment advances including therapies currently under clinical investigation.

Frequency of O⁶-methylguanine-DNA methyltransferase promoter methylation in cytological samples from small cell lung cancer

BACKGROUND

In a phase II study for patients with relapsed small cell lung cancer (SCLC), the administration of Temozolomide, an alkylating agent used in gliomas and anaplastic astrocytoma, showed a effective activity when O(6) -methylguanine-DNA methyltransferase (MGMT) gene promoter was methylated.

METHODS

We tested the feasibility of MGMT promoter status evaluation in small biopsies and cytological specimens routinely processed for diagnostic purposes. We tested samples from 56 patients with SCLC: 30 tissue biopsies, 17 fine-needle aspiration biopsy, 8 bronchial washing, and 1 was a sputum. Biopsies and fine-needle aspiration biopsy were fixed in formalin, bronchial washing and sputum in Dubosq Brazil. DNA was extracted after macrodissection of the areas containing the maximum number of cancer cells. MGMT promoter methylation status was assessed by methylation specific PCR.

RESULTS

Methylation analysis was obtained in 54 samples (54/56) and failed in two bronchial wash. MGMT promoter was methylated in 35.2% of the cases without any significant difference between histological and cytological samples (37.9% vs. 32%).

CONCLUSION

MGMT promoter methylation is present in SCLC and cytological samples are perfectly adequate for methylation analysis, even if they were taken during routine diagnostic procedures, using different fixative and with low number and percentage of cancer cells.

Knockdown of SUMO-activating enzyme subunit 2 (SAE2) suppresses cancer malignancy and enhances chemotherapy sensitivity in small cell lung cancer

Background

SUMO-activating enzyme subunit 2 (SAE2) is the sole E1-activating enzyme required for numerous important protein SUMOylation, abnormal of which is associated with carcinogenesis. SAE2 inactivation was recently reported to be a therapeutic strategy in cancers with Myc overexpression. However, the roles of SAE2 in small cell lung cancer (SCLC) are largely unknown.

Methods

Stably SAE2 knockdown in H446 cells were established with a lentiviral system. Cell viability, cell cycle, and apoptosis were analyzed using MTT assay and flow cytometric assay. Expression of SAE2 mRNA and protein were detected by qPCR, western blotting, and immunohistochemical staining. Cell invasion and migration assay were determined by transwell chamber assay. H446 cells with or without SAE2 knockdown, nude mice models were established to observe tumorigenesis.

Results

SAE2 was highly expressed in SCLC and significantly correlated with tumorigenesis in vivo. Cancer cells with RNAi-mediated reduction of SAE2 expression exhibited growth retardation and apoptosis increasing. Furthermore, down-regulation of SAE2 expression inhibited migration and invasion, simultaneously increased the sensitivity of H446 to etoposide and cisplatin.

Conclusions

SAE2 plays an important role in tumor growth, metastasis, and chemotherapy sensitivity of H446 and is a potential clinical biomarker and therapeutic target in SCLC with high c-Myc expression.

Electronic supplementary material

The online version of this article (doi:10.1186/s13045-015-0164-y) contains supplementary material, which is available to authorized users.

Effects of chemotherapy on survival of elderly patients with small-cell lung cancer: analysis of the SEER-medicare database

INTRODUCTION

This retrospective cohort study was designed to analyze factors associated with administration of chemotherapy and to examine the impact of chemotherapy on survival among elderly patients with small-cell lung cancer (SCLC) in the community.

METHODS

Elderly patients aged 65 years and older with SCLC diagnosed between 1992 and 2001 were selected from the Surveillance, Epidemiology, and End Results-Medicare database. Logistic regression was used to evaluate which covariates influenced receipt of chemotherapy. Cox proportional hazards regression was used to examine the influence of clinical and demographic variables on survival. The independent effect of chemotherapy on survival was determined using propensity scores and quantile regression.

RESULTS

In the final cohort of 10,428 patients, 67.1% received chemotherapy, 39.1% received radiation, 3.4% received surgery, and 21.8% received no treatment. The most common chemotherapy regimens included etoposide combined with either cisplatin or carboplatin. Patients aged 85 years and older were significantly less likely to receive chemotherapy compared with patients aged 65 to 69 years (odds ratio 0.17; 95% confidence interval 0.14-0.21). Median survival for all patients was 7 months. Factors associated with improved survival were being female, black race, having limited-stage disease, receiving any treatment, and having a lower comorbidity score. Quantile regression demonstrated that chemotherapy provided a 6.5-month improvement in median survival (95% confidence interval 6.3-6.6; p<0.001).

CONCLUSIONS

Statistically significant differences in the receipt of chemotherapy exist among elderly patients with SCLC. Chemotherapy is associated with a greater than 6-month improvement in median survival among elderly patients with SCLC, even in patients over the age of 80 years.

Lung cancer stigma, anxiety, depression, and quality of life

This study investigated lung cancer stigma, anxiety, depression, and quality of life (QOL) and validated variable similarities between ever and never smokers. Patients took online self-report surveys. Variable contributions to QOL were investigated using hierarchical multiple regression. Patients were primarily White females with smoking experience. Strong negative relationships emerged between QOL and anxiety, depression and lung cancer stigma. Lung cancer stigma provided significant explanation of the variance in QOL beyond covariates. No difference emerged between smoker groups for study variables. Stigma may play a role in predicting QOL. Interventions promoting social and psychological QOL may enhance stigma resistance skills.

Combined MET inhibition and topoisomerase I inhibition block cell growth of small cell lung cancer

Small cell lung cancer (SCLC) is a devastating disease, and current therapies have not greatly improved the 5-year survival rates. Topoisomerase (Top) inhibition is a treatment modality for SCLC; however, the response is short lived. Consequently, our research has focused on improving SCLC therapeutics through the identification of novel targets. Previously, we identified MNNG HOS transforming gene (MET) to be overexpressed and functional in SCLC. Herein, we investigated the therapeutic potential of combinatorial targeting of MET using SU11274 and Top1 using 7-ethyl-10-hydroxycamptothecin (SN-38). MET and TOP1 gene copy numbers and protein expression were determined in 29 patients with limited (n = 11) and extensive (n = 18) disease. MET gene copy number was significantly increased (>6 copies) in extensive disease compared with limited disease (P = 0.015). Similar TOP1 gene copy numbers were detected in limited and extensive disease. Immunohistochemical staining revealed a significantly higher Top1 nuclear expression in extensive (0.93) versus limited (0.15) disease (P = 0.04). Interestingly, a significant positive correlation was detected between MET gene copy number and Top1 nuclear expression (r = 0.5). In vitro stimulation of H82 cells revealed hepatocyte growth factor (HGF)-induced nuclear colocalization of p-MET and Top1. Furthermore, activation of the HGF/MET axis enhanced Top1 activity, which was abrogated by SU11274. Combination of SN-38 with SU11274 dramatically decreased SCLC growth as compared with either drug alone. Collectively, these findings suggest that the combinatorial inhibition of MET and Top1 is a potentially efficacious treatment strategy for SCLC.