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

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.

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.

Evaluation of factors associated with platinum-sensitivity status and survival in limited-stage small cell lung cancer patients treated with chemoradiotherapy

In this retrospective study, we analyzed the association of clinicopathological factors and therapeutic plans with platinum-sensitivity status and survival of limited-stage small cell lung cancer (LS-SCLC) patients. We enrolled 452 LS-SCLC patients with 279 platinum sensitive and 173 platinum refractory patients. The low serum neuro-specific enolase levels (NSE; p = 0.011), neutrophil-to-lymphocyte ratios (NLR; p = 0.013) and higher objective response rates (p = 0.003) were associated with sensitive group but not the refractory group. Multivariate analysis showed that treatment modality (HR = 0.267, p < 0.001), serum lactate dehydrogenase (LDH; HR = 1.894, p = 0.016), NLR (HR = 2.043, p = 0.043) and platinum-sensitivity status (HR = 0.561, p = 0.036) were independent prognostic factors for survival. We further showed that the numbers of chemotherapy cycles and response to first-line therapy were independent prognostic factors for refractory patients only. Our study demonstrates that platinum-sensitivity status is of prognostic importance, as it is strongly associated with survival in LS-SCLC patients.

Prognostic value of Ki-67 expression in patients with extensive-stage small cell lung cancer

AIM

To determine whether Ki-67 has prognostic significance in patients with extensive-stage small cell lung cancer.

PATIENTS & METHODS

A retrospective review identified 159 consecutive patients with extensive-stage small cell lung cancer. Ki-67 expression level at the time of diagnosis was retrieved. Survival was assessed by Kaplan-Meier method and long-rank test.

RESULTS

None of the clinical characteristics, including age, gender and lactate dehydrogenase, were significantly associated with Ki-67 expression level (p > 0.05). Patients with high Ki-67 expression had longer survival than patients with low Ki-67 expression (p = 0.078). Age, gender and lactate dehydrogenase were not significantly associated with survival (p > 0.05).

CONCLUSION

Ki-67 expression level failed to have a markedly significant impact on survival in patients with extensive-stage small cell lung cancer.

Impact of Radiation Therapy in Surgically Resected Limited-Stage Small Cell Lung Carcinoma

PURPOSE

To elucidate the role of radiation therapy (RT) in the treatment of surgically resected limited-stage small cell lung carcinoma (LSCLC).

METHODS

We queried the SEER database from 1998 to 2012 to identify patients who were diagnosed with LSCLC as their only primary tumor. Kaplan-Meier analysis was utilized to determine disease-specific survival (DSS) and overall survival (OS), while multivariate analysis was used to compare survival in terms of patients and treatment characteristics.

RESULTS

Eight hundred twenty-three LSCLC patients were identified for inclusion within the study. 12-month DSS for patients who did not receive surgery or RT was 31.9% (95% CI 27.7-36.3), 93.3% (95% CI 71.6-90.5) for surgery alone, and 81.0% (95% CI 69.3-88.6) for surgery + RT. 12-month OS was 27.2% (95% CI 23.4-31.1), 74.7% (95% CI 62.6-83.4), and 78.3% (95% CI 66.4-86.4) for no surgery or RT, for surgery alone, and for surgery + RT, respectively. In terms of multivariate analysis, patients receiving surgery alone and patients receiving surgery + RT had a better DSS and OS than those who received neither treatment. However, OS (HR 1.60; 95% CI 0.93-2.75, p = 0.09) and DSS (HR 1.34; 95% CI 0.72-2.51, p = 0.37) were not significantly associated with patients receiving surgery alone compared to surgery + RT.

CONCLUSIONS

Surgery alone and surgery + RT were positively associated with DSS and OS compared to patients who did not receive surgery or RT. However, the addition of RT to surgery did not significantly predict DSS or OS compared to surgery alone.

Neuron-specific enolase and response to initial therapy are important prognostic factors in patients with small cell lung cancer

PURPOSE

The prognostic factors for the survival of small cell lung cancer (SCLC) patients are still widely debated. The aim of this study was to identify the clinical features and prognostic factors in SCLC patients.

METHODS

A retrospective study was conducted on SCLC patients who were treated in our hospital between July 2010 and July 2015. Comparison of overall survival (OS) was performed using the Kaplan-Meier method. Prognostic factors for OS were identified by multivariate Cox regression models.

RESULTS

A total of 523 patients with complete data and ECOG 0-2 were enrolled in our study. A total of 383 patients (73.2%) were diagnosed with ES-SCLC (extensive-stage SCLC) and 140 patients (26.8%) were diagnosed with LS-SCLC (limited-stage SCLC). In all patients, early disease stage, good ECOG, normal neuron-specific enolase (NSE), thoracic radiotherapy, ≥4 cycles of chemotherapy, prophylactic cranial irradiation, good response to initial therapy were independent favorable prognostic factors for OS, along with gender, age, CEA and CA125. In LS-SCLC patients, normal NSE, normal CEA, good response to initial therapy and surgery were independent favorable prognostic factors for OS. In ES-SCLC patients, good ECOG, normal NSE, thoracic radiotherapy, ≥4 cycles of chemotherapy, prophylactic cranial irradiation and good response to initial therapy were independent favorable prognostic factors for OS. Remarkably, NSE and response to initial therapy were independent prognostic factors for OS in all SCLC patients, LS-SCLC patients and ES-SCLC patients.

CONCLUSION

The normal NSE and good response to initial therapy predicted a better survival for SCLC patients, regardless of disease stage.

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.

The value of prognostic factors in Chinese patients with small cell lung cancer: A retrospective study of 999 patients

INTRODUCTION

Little is known about the prognostic factors for small cell lung cancer (SCLC) in Chinese patients.

OBJECTIVE

The aim of this retrospective study was to improve our understanding of overall survival (OS) and progression-free survival (PFS) prognostic factors in Chinese patients with SCLC.

METHODS

A retrospective analysis of 999 SCLC cases was performed. Patient characteristics, treatments, and laboratory data, including platelet counts and serum lactate dehydrogenase (LDH) and serum sodium levels, were collected. Potential prognostic factors for OS and PFS were evaluated by univariate and multivariate analyses.

RESULTS

The median OS and PFS were 10.6 and 7.0 months, respectively. The multivariate Cox proportional hazards model was used to identify stage, serum LDH, and several therapy-relevant factors, including the initial chemotherapy regimen, number of initial chemotherapy cycles, and combination therapy, as independent prognostic factors for OS. Furthermore, female sex, normal LDH levels, a response to therapy, receiving six cycles of initial chemotherapy, and receiving chemotherapy combined with radiotherapy and/or surgery were favorable prognostic factors for PFS. In addition, patients with hyponatremia had a worse OS; therefore, hyponatremia could not influence survival when a good response to therapy was achieved, and it failed to predict PFS.

CONCLUSIONS

This study demonstrated that several factors, including patient, tumor, and treatment characteristics and serum LDH levels are independent prognostic factors for OS and PFS in Chinese patients with SCLC. The identification of such factors will help physicians compare different populations and to interpret the contribution of treatment to differences in survival among groups.

Prognostic Factor Analysis in Patients With Small-Cell Lung Cancer Treated With Third-Line Chemotherapy

BACKGROUND

There is little information on the clinical outcome of patients with small-cell lung cancer (SCLC) treated with third-line chemotherapy. The purpose of this study was to clarify the prognostic factors of SCLC patients receiving third-line chemotherapy.

PATIENTS AND METHODS

Between November 2001 and October 2011, 202 of 648 consecutive SCLC patients at the National Cancer Center Hospital East received third-line chemotherapy. Multivariate Cox regression analysis was performed to identify the prognostic factors for overall survival after third-line chemotherapy.

RESULTS

The demographics of the 202 patients were as follows: median age 66 years, 83% male, and Eastern Cooperative Oncology Group (ECOG) performance status (PS) 0, 1, 2, and 3 values of 22, 122, 49, and 9, respectively. Median time to treatment failure after second-line chemotherapy (TTF2) was 4.5 months (TTF2 ≥ 5/< 5 months, 82/120). The median overall survival after third-line chemotherapy was 5.1 months. Multivariate Cox regression analysis showed that PS 0-1 (hazard ratio, 0.38; 95% confidence interval, 0.27-0.54; P < .001) and TTF2 ≥ 5 months (hazard ratio, 0.57; 95% confidence interval, 0.41-0.79; P < .001) were independent prognostic factors. TTF2 threshold of 5 months was determined on the basis of concordance probability adjusted by PS.

CONCLUSION

PS 0-1 and TTF2 ≥ 5 months were associated with a favorable prognosis among SCLC patients receiving third-line chemotherapy. These 2 factors might be helpful for the selection of candidates for third-line chemotherapy and for patient stratification when conducting future clinical trials in the third-line setting.

Nomograms Predict Overall Survival for Patients with Small-Cell Lung Cancer Incorporating Pretreatment Peripheral Blood Markers

BACKGROUND

We sought to build prognostic nomograms and identify novel prognostic factors in small-cell lung cancer (SCLC) incorporating both clinical data and peripheral blood markers.

METHODS

We analyzed 938 patients with SCLC (555 extensive stage SCLC [ES-SCLC] and 383 limited stage SCLC [LS-SCLC]) diagnosed between 1997 and 2012 from a single institution. We investigated the prognostic value of pretreatment neutrophil to lymphocyte ratio, platelet to lymphocyte ratio, red cell distribution width, hemoglobin, and other clinicopathological factors. Cox proportional hazards models determined the effects of multiple factors on overall survival (OS). Two nomograms were developed to predict median survival and 6- and 12-month OS for ES-SCLC, and 1- and 2-year OS for LS-SCLC.

RESULTS

In ES-SCLC, the multivariate Cox model identified neutrophil to lymphocyte ratio and red cell distribution width as significant prognostic factors for OS independent of age, Eastern Cooperative Oncology Group performance score, chest radiation, chemotherapy, liver metastases, and numbers of metastatic sites. In LS-SCLC, significant prognostic variables included platelet to lymphocyte ratio, age, smoking cessation, chest radiation, chemotherapy, surgery, and prophylactic cranial irradiation. The two nomograms show good accuracy in predicting OS, with a concordance index of 0.73 in both ES- and LS-SCLC.

CONCLUSION

The two nomograms incorporating hematological markers could more accurately predict individualized survival probability of SCLC than the existing models.

A New Score for Estimating Survival After Definitive Radiochemotherapy of Limited Disease Small Cell Lung Cancers

INTRODUCTION

Most patients with limited disease small cell lung cancer (LD-SCLC) receive definitive radiochemotherapy. Some patients cannot withstand combined modality treatments. Patients with short life expectancies should receive less time-consuming programs. For patients with favorable prognoses, cure while avoiding late toxicity is important. Personalized treatment programs are required. An instrument to estimate the survival after radiochemotherapy of LD-SCLC was created.

METHODS

Seventy-one patients receiving definitive radiochemotherapy for LD-SCLC were retrospectively analyzed. Eight factors were evaluated for survival including gender, age, Karnofsky performance score, T-stage, N-stage, tumor substage, number of pack years, and pre-radiotherapy hemoglobin level. Factors that were significant (p < 0.05) or showed a trend (p ≤ 0.08) on multivariate analyses were incorporated in the score. Scoring points were derived from 2-year survival rates divided by 10 and added to scores for individual patients.

RESULTS

On multivariate analysis, gender (p = 0.03), performance score (p < 0.001), and pre-radiotherapy hemoglobin level (p = 0.04) were significant, and tumor substage showed a trend (p = 0.08). Taking into account the 2-year survival rates of these factors, scores for single patients ranged from 9 to 26 points. Three groups were identified: 9-13, 14-18, and 19-26 points. One-year survival rates were 8, 73, and 100 %, respectively (p < 0.001). Two-year survival rates were 0, 35, and 87 %, respectively (p < 0.001). The 3-year survival rates were 0, 19, and 75 %, respectively (p < 0.001).

CONCLUSION

This score including three groups with significantly different survival rates is a helpful instrument for personalization of therapy for patients with LD-SCLC. When using this instrument, the limitations if this study must be taken into account.

Apolipoproteins as Differentiating and Predictive Markers for Assessing Clinical Outcomes in Patients with Small Cell Lung Cancer

PURPOSE

The present study aimed to investigate the value of apolipoproteins, including ApoA-1, ApoC-III, and ApoE, in patients with small cell lung cancer (SCLC) as potential biomarkers for diagnosis, prognosis, and cancer progression.

MATERIALS AND METHODS

Lung samples were collected from 89 patients with SCLC. Nineteen lung samples from non-small cell lung cancer (NSCLC) patients and 12 normal lung tissues were used as controls. Expression profiles of ApoA-1, ApoC-III, and ApoE in different samples were examined using immunohistochemical methods, and the expression levels were correlated with cancer types, treatment, and outcomes using chi-square and Mann-Whitney tests.

RESULTS

Expression of ApoA-1 and ApoC-III in SCLC was significantly different, compared with that in NSCLC and normal lung tissues, and was correlated with recurrence of SCLC. Patients undergoing neoadjuvant chemotherapy before surgery showed significantly reduced expression of ApoA-1 and increased expression of ApoC-III and ApoE. Nevertheless, the expression levels of ApoA-1, ApoC-III, and ApoE were not correlated with SCLC staging.

CONCLUSION

ApoA-1 and ApoC-III may be used as differentiating and predictive markers for SCLC. ApoA-1, ApoC-III, and ApoE may be used to monitor the efficacy of chemotherapy.

The prognostic value of whole blood SOX2, NANOG and OCT4 mRNA expression in advanced small-cell lung cancer

BACKGROUND

The data on expression and clinical impact of cancer stem cell markers SOX2, NANOG and OCT4 in lung cancer is still lacking. The aim of our study was to compare SOX2, NANOG and OCT4 mRNA expression levels in whole blood between advanced small-cell lung cancer (SCLC) patients and healthy controls, and to correlate mRNA expression with progression-free survival (PFS) after first-line chemotherapy and overall survival (OS) in advanced SCLC patients.

PATIENTS AND METHODS

50 advanced SCLC patients treated with standard chemotherapy and followed at University Clinic Golnik, Slovenia, between 2009 and 2013 were prospectively included. SOX2, NANOG and OCT4 mRNA expression levels were determined using TaqMan qPCR in whole blood collected prior to chemotherapy. Whole blood of 34 matched healthy individuals with no cancerous disease was also tested.

RESULTS

SOX2 mRNA expression was significantly higher in whole blood of SCLC patients compared to healthy controls (p = 0.006). Significant correlation between SOX2 mRNA expression levels and the number of distant metastatic sites was established (p = 0.027). In survival analysis, patients with high SOX2 expression had shorter OS (p = 0.017) and PFS (p = 0.046). In multivariate Cox analysis, an independent value of high SOX2 expression for shorter OS (p = 0.002), but not PFS was confirmed. No significant differences were observed for NANOG or OCT4 expression levels when comparing SCLC patients and healthy controls neither when analysing survival outcomes in SCLC patients.

CONCLUSIONS

SOX2 mRNA expression in whole blood might be a promising non-invasive marker for molecular screening of SCLC and important prognostic marker in advanced chemotherapy-treated SCLC patients, altogether indicating important role of cancer stem-like cell (CSC) regulators in cancer spread. Further evaluation of SOX2 as a possible screening/prognostic marker and a therapeutic target of SCLC is warranted.

Systemic Immune-inflammation Index, Based on Platelet Counts and Neutrophil-Lymphocyte Ratio, Is Useful for Predicting Prognosis in Small Cell Lung Cancer

Small cell lung cancer (SCLC) is an aggressive disease characterized by rapid growth and metastases. It has been recognized that the inflammation of the microenvironment plays a critical role in the development of malignancies. However, little is known about the role of multiple inflammatory and hematological markers in the prognosis of SCLC. The aim of this study was to determine the clinical significance of pre-treatment inflammation-based scores and characteristics as prognostic indicators for the survival of SCLC patients. A retrospective analysis of 919 SCLC cases was performed. Patients' characteristics and hematologic tests data at initial diagnosis were collected. The univariate analysis of all SCLC patients indicated that favorable prognostic factors were age ˂ 70 years, non-smokers, good performance status, limited disease and response to treatment. Moreover, univariate analysis of inflammation-based scores and other blood parameters showed that neutrophil-lymphocyte ratio ≥ 5, platelet-lymphocyte ratio ≥ 250, systemic immune-inflammation index (SII) ≥ 1,600 × 10(9)/L, prognostic nutritional index (albumin + 5 × lymphocyte) < 45, and elevated serum lactate dehydrogenase (LDH) predicted poor prognosis in SCLC patients. SII represents the score that is calculated as follows: platelet count × neutrophil count/lymphocyte count. In the multivariate analysis, SII, together with serum LDH, stage and response to therapy, were associated with overall survival (OS). This study demonstrated that the combination of platelet count and neutrophil-lymphocyte ratio could help to predict poor prognosis in SCLC. Our findings will facilitate the understanding of survival differences in SCLC patients in clinical practice.

Prognostic significance of standardised uptake value (SUVmax ) measured on 18F-fluorodeoxyglucose positron emission tomography/computed tomography in patients with small cell lung cancer

Certain prognostic factors for small cell lung cancer (SCLC) have been validated, but the prognostic role of 18F-FDG PET/CT still remains unclear. The aim of this study was to evaluate the prognostic significance of 18F-FDG PET/CT in patients with SCLC. We reviewed 142 patients with pathologically proven SCLC who underwent pre-treatment 18F-FDG PET/CT. Standardised uptake value (SUV_max ) and other potential prognostic variables were chosen for analysis. The mean age of the study population was 58.2 ± 10.1 years (range, 25-84), and 124 (87.3%) patients were men. The median SUV_max value was 11.6 (4.0-29.3). Among the variables included in the univariate analysis, performance status (P = 0.001), disease stage (P < 0.001), administration of thoracic radiotherapy (TRT; P < 0.001), albumin level (P = 0.030) and LDH level (P < 0.001) showed prognostic significance. Further, multivariate analysis showed that performance status (P = 0.007), albumin level (P = 0.002), LDH level (P < 0.001) and administration of TRT (P = 0.001) were independent prognostic factors for survival. In conclusion, performance status, TRT, LDH level and albumin level were identified as important prognostic factors, while 18F-FDG PET/CT uptake of the primary lesions did not have any prognostic significance for survival in patients with SCLC.

Benefit from thoracic radiotherapy in patients with extensive-disease small-cell lung cancer with elevated lactate dehydrogenase

Background

High lactate dehydrogenase (LDH) is associated with a large tumor burden in extensive-disease small-cell lung cancer (ED-SCLC). This study evaluated the benefit of additional thoracic radiotherapy (TRT) in patients with ED-SCLC with elevated LDH.

Methods

We analyzed 94 patients with ED-SCLC and evaluated LDH at Sun Yat-sen University Cancer Center during the period between January 2000 and March 2010. Patients were divided into two groups according to whether TRT was received. Survival was evaluated by the Kaplan–Meier method and Cox’s regression analysis.

Results

The median age of the 94 patients with ED-SCLC was 58.5 years. The main metastatic sites included the liver, bone, brain, and adrenal glands. The response rate in the TRT group was 46.9%. There were 32 patients (34.04%) receiving TRT and 5.3% receiving prophylactic cranial irradiation. The median survival time reached 10 months (95% confidence interval: 8.22, 11.78 months), and the 1-, 2-, and 5-year survival rates were 43.6%, 11.7%, and 2.1%, respectively. There was a significant difference in the median progression-free survival (PFS) and overall survival (OS) between the TRT group and the no TRT group (PFS: 9.0 months vs 6.0 months, P=0.018; OS: 13.0 months vs 9.0 months, P=0.006).

Conclusion

The use of TRT improves the survival of patients with ED-SCLC. Future studies should use the LDH level for categorizing patients for treatment.

Prognostic value of fluorine-18 fludeoxyglucose positron emission tomography parameters differs according to primary tumour location in small-cell lung cancer

OBJECTIVE

To investigate the prognostic value of fluorine-18 fludeoxyglucose (FDG) positron emission tomography (PET) parameters for small-cell lung cancer (SCLC), according to the primary tumour location, adjusted by conventional prognostic factors.

METHODS

From 2008 to 2013, we enrolled consecutive patients with histologically proven SCLC, who had undergone FDG-PET/CT prior to initial therapy. The primary tumour location was categorized into central or peripheral types. PET parameters and clinical variables were evaluated using univariate and multivariate analysis.

RESULTS

A total of 69 patients were enrolled in this study; 28 of these patients were categorized as having the central type and 41 patients as having the peripheral type. In univariate analysis, stage, serum neuron-specific enolase, whole-body metabolic tumour volume (WB-MTV) and whole-body total lesion glycolysis (WB-TLG) were found to be significant in both types of patients. In multivariate analysis, the independent prognostic factor was found to be stage in the central type, but WB-MTV and WB-TLG in the peripheral type. Kaplan-Meier analysis demonstrated that patients with peripheral type with limited disease and low WB-MTV or WB-TLG showed significantly better overall survival than all of the other groups (p < 0.0083).

CONCLUSION

The FDG-PET volumetric parameters were demonstrated to be significant and independent prognostic factors in patients with peripheral type of SCLC, while stage was the only independent prognostic factor in patients with central type of SCLC.

ADVANCES IN KNOWLEDGE

FDG-PET is a non-invasive method that could potentially be used to estimate the prognosis of patients, especially those with peripheral-type SCLC.

Teniposide-loaded multilayer modified albumin nanoparticles with increased passive delivery to the lung

The structure of the albumin core and multi-coated layers are designed to encapsulate teniposide for achieving controlled release and passively targeted delivery to the lung.

The Role of 18F-FDG PET/CT on Staging and Prognosis in Patients with Small Cell Lung Cancer

BACKGROUND

We evaluated 18F-FDG PET/CT in small cell lung cancer (SCLC) staging and assessed metabolic (SUVmax, MTV and TLG) and morphologic (CTvol) variables as predictors for overall survival (OS) and progression-free survival (PFS).

METHODS

Patients with newly diagnosed, histopathology-confirmed SCLC, who underwent 18F-FDG PET/CT were evaluated. A Cox proportional hazard model was used to determine the association between the primary tumour SUVmax, MTV, TLG and CTvol with OS and PFS. Similar evaluations were performed when hilar/mediastinal lymphadenopathy was included [total SUVmax (TSUVmax), total MTV (TMTV) and total TLG (TTLG)].

RESULTS

55 patients were included. 18F-FDG PET/CT changed staging in 6/55 (10.9%) patients who were upstaged to extensive disease. TTLG (>443.8) was a significant variable for OS with HR=2.1 (CI 1.14-3.871, p=0.017). Patients with TTLG>443.8 had a median OS of 13.4 months compared to 25.7 months in patients with TTLG<443.8 (p=0.018). TMTV (>72.4) was significant for PFS with HR=2.3 (CI 1.11-4.8, p=0.025). A median PFS of 12.1 and 26.2 months was found with TMTV greater and less than 72.4, respectively (p=0.005).

CONCLUSIONS

18F-FDG PET/CT improved staging of patients with SCLC, and TTLG and TMTV can be used as prognostic variables for OS and PFS, respectively.

KEY POINTS

• Identifying variables that predict the prognosis of patients with SCLC is important. • 18F-FDG PET/CT influences staging of patients with SCLC. • Metabolic parameters could be used as predictors for PFS and OS.

Prognostic significance of circulating tumor cells in small--cell lung cancer patients: a meta-analysis

Circulating tumor cells (CTCs) are believed to be particularly important and a reliable marker of malignancy. However, the prognostic significance of CTCs detected in patients with small cell lung cancer (SCLC) is still unclear. We therefore aimed to assess the prognostic relevance of CTCs using a meta-analysis. We searched PubMed for relevant studies and statistical analyses were conducted to calculate the hazard ratio (HR) and 95% confidence intervals (CIs) using fixed or random-effect models according to the heterogeneity of included studies. A total of 7 papers covering 440 SCLC patients were combined in the final analysis. The meta-analysis revealed that CTCs were significantly associated with shorter overall survival (HR=1.9; 95%CI: 1.19-3.04; Z=2.67; P<0.0001) and progression-free survival (HR=2.6; 95%CI: 1.9-3.54; Z=6.04; P<0.0001). The results thus suggest that the presence of CTCs indicates a poor prognosis in patients with SCLC. Further well-designed prospective studies are required to explore the clinical applications of CTCs in SCLC.

Small cell lung carcinoma: staging, imaging, and treatment considerations

Small cell lung carcinoma (SCLC) is the most common primary pulmonary neuroendocrine malignancy and is characterized by a rapid doubling time and high growth fraction. Approximately 60%-70% of patients present with metastatic disease at the time of diagnosis, and their prognosis is poor. However, improved survival has been demonstrated when SCLC is diagnosed early and specific treatment strategies are used. A modified version of the Veterans Administration Lung Cancer Study Group (VALSG) staging system has traditionally been used to categorize SCLC as limited-stage or extensive-stage disease to guide therapy. However, the International Association for the Study of Lung Cancer has recommended that the current seventh edition of the American Joint Committee on Cancer tumor-node-metastasis staging system for lung cancer replace the VALSG system for staging of SCLC. Appropriate staging and patient management require knowledge of imaging manifestations of SCLC across multiple imaging modalities, the strengths and weaknesses of specific examinations, the correlation of these findings with the staging criteria used in clinical practice, and the impact of appropriate staging on patient treatment and survival. Computed tomography (CT) is primarily used to evaluate the primary tumor and the extent of intrathoracic disease. In recent years, however, 2-[fluorine-18]fluoro-2-deoxy-d-glucose positron emission tomography/CT has proved to be more accurate than conventional imaging in the staging of SCLC and can be used to guide therapy and assess treatment response.

A retrospective study of risk and prognostic factors in relation to lower respiratory tract infection in elderly lung cancer patients

Lung cancer (LCa) is one of the most common and deadly malignancies in elderly patients. During the course of the disease, these patients frequently present with lower respiratory tract infection. Therefore, this study aims to investigate the clinical features of lower respiratory tract infection in elderly LCa patients and evaluate the impact on overall survival rate. Clinical and laboratory data were analyzed retrospectively for a total of 1936 patients that were over 60-years-old. Patients were classified into three groups based on pulmonary diseases: Group 1, lung cancer (LCa); Group 2, chronic obstructive pulmonary disease (COPD); and Group 3, other medical diseases without pulmonary problems (OMD). Univariate and multivariate analysis were used to evaluate related risk factors of infections and prognostic factors. The infection rate of the LCa group (46.25%) was significantly higher than the COPD (31.40%) and OMD (23.33%) groups. Polymicrobial infections were most prevalent in the LCa group (28.75%), which far exceeded the prevalence in COPD (11.05%) and OMD (4.44%) groups. In LCa patients, the most frequent pathogens were Gram-negative bacteria (44.87%), followed by fungi (34.62%) and Gram-positive bacteria (20.51%), the major pattern of polymicrobial infections was mixed Gram-negative bacteria and fungi (43.48%). Multivariate analysis revealed that COPD, pleural effusion, anatomical type, low cellular immune function, and length of hospital stay were related risk factors of lower respiratory tract infection in elderly LCa patients. A multivariate Cox proportional hazards regression model revealed that age, stage of TNM, surgical resection, antitumor therapy, lower respiratory tract infection, COPD, and pleural effusion were independent prognostic factors for cancer-related death. Patients who received effective antimicrobial treatment had a better outcome than those who did not respond to antimicrobial drugs (HR = 0.458, P < 0.05). Understanding lower respiratory tract infection in elderly LCa patients is vital if we are to set up corresponding measures and to target effective antimicrobial treatment.

Prognostic significance of the lymphocyte-to-monocyte ratio in patients with small cell lung cancer

We investigated the role of the lymphocyte-to-monocyte ratio (LMR) at diagnosis in patients with small cell lung cancer (SCLC) treated with standard chemotherapy. We retrospectively reviewed all SCLC patients who received frontline platinum-based chemotherapy or chemoradiotherapy. The cut-off LMR value at diagnosis was 4.19 according to time-dependent receiver-operating characteristic analysis. A total of 188 patients were divided into two groups according to the LMR at diagnosis (low vs. high LMR). Of the 171 patients evaluated for treatment response, 14 (12.4%) in the low LMR group and 1 (1.7%) in the high LMR group were non-responders (p = 0.025). In the whole patient cohort, progression-free survival and overall survival were significantly shorter in the low LMR group (low vs. high: median 6.4 vs. 7.1 months, p = 0.001; median 10.6 vs. 13.1 months, p = 0.003, respectively). On multivariate analysis, a low LMR at diagnosis was an independent unfavourable prognostic factor for predicting survival. The LMR at diagnosis could be helpful for predicting prognosis in SCLC.

Importance of ABCC1 for cancer therapy and prognosis

Multidrug resistance presents one of the most important causes of cancer treatment failure. Numerous in vitro and in vivo data have made it clear that multidrug resistance is frequently caused by enhanced expression of ATP-binding cassette (ABC) transporters. ABC transporters are membrane-bound proteins involved in cellular defense mechanisms, namely, in outward transport of xenobiotics and physiological substrates. Their function thus prevents toxicity as carcinogenesis on one hand but may contribute to the resistance of tumor cells to a number of drugs including chemotherapeutics on the other. Within 48 members of the human ABC superfamily there are several multidrug resistance-associated transporters. Due to the well documented susceptibility of numerous drugs to efflux via ABC transporters it is highly desirable to assess the status of ABC transporters for individualization of treatment by their substrates. The multidrug resistance associated protein 1 (MRP1) encoded by ABCC1 gene is one of the most studied ABC transporters. Despite the fact that its structure and functions have already been explored in detail, there are significant gaps in knowledge which preclude clinical applications. Tissue-specific patterns of expression and broad genetic variability make ABCC1/MRP1 an optimal candidate for use as a marker or member of multi-marker panel for prediction of chemotherapy resistance. The purpose of this review was to summarize investigations about associations of gene and protein expression and genetic variability with prognosis and therapy outcome of major cancers. Major advances in the knowledge have been identified and future research directions are highlighted.

[First-line chemotherapy and its survival analysis of 394 patients with extensive-stage small cell lung cancer in a single institute]

BACKGROUND AND OBJECTIVE

Small cell lung cancer (SCLC) is the most malignant neuroendocrine tumor but highly sensitive to chemotherapy and radiotherapy. At present, the standard first-line chemotherapy regimen of extensive-stage SCLC is platinum combined etoposide regimen. However, most patients who receive first-line chemotherapy will relapse within one to two years. Once recurrent, it indicates poor prognosis. In this study, we analyzed the survival among all extensive-stage SCLC and patients who received first-line chemotherapy and determined prognostic factors.

METHODS

Total of 394 patients who were diagnosed as extensive-stage small cell lung cancer from February 2001 to December 2011 hospitalized in Peking Union Medical College Hospital were collected. Kaplan-Meier method was used to calculate the overall survival (OS) and progression-free survival (PFS). Univariate analysis and Cox regression analysis were used to detect the influence factors of survival.

RESULTS

The median OS of all extensive-stage small cell lung cancer was 14.8 months; 1-year, 2-year and 5-year survival rates were 58.9%, 27.2% and 7.8%, respectively. According to the results of univariate and Cox multivariate analysis, OS of extensive-stage SCLC was closely associated with age (P=0.006), ECOG PS (P=0.021), liver metastasis (P<0.001), bone metastasis (P<0.001) and chemotherapy (P<0.001). The mortality risk of patients who didn't receive chemotherapy was 4.919 times higher than that who received; the mortality risk of patients without liver, bone metastasis was reduced by approximately 50 percent. The first-line chemotherapy was mainly EP (DDP+VP-16) or CE (CBP+VP-16) regimens (accounting for 82.8%) with 4-6 cycles. The median OS and PFS in first-line chemotherapy were 15.1 months and 7.5 months, respectively. The result of Cox regression analysis indicated that OS in first-line chemotherapy was remarkably related to smoking history (P=0.041), liver metastasis (P<0.001), bone metastasis (P<0.001), chemotherapy cycle number (P<0.001); PFS was relevant with smoking history (P=0.003), liver metastasis (P=0.001), bone metastasis (P<0.001), chemotherapy cycle number (P<0.001). Thoracic radiotherapy was not an independent influence factor of OS and PFS in extensive-stage small cell lung cancer.

CONCLUSIONS

The patients who were younger than 60-year old, with good KPS, absence of liver and bone metastasis had better prognosis. Patients should receive chemotherapy with first-line standard regimen (CE/EP regimen). It was beneficial to survival if the effect of first-line chemotherapy was SD or PR-CR and the proper chemotherapy cycle number was 4-6 cycles. The role of thoracic radiotherapy in extensive-stage small cell lung cancer needed to be investigated further.

Progress in the management of limited-stage small cell lung cancer

Approximately 15% of lung cancer cases are of the small cell subtype, but this variant is highly aggressive and is often diagnosed at advanced stages. Outcomes after current treatment regimens have been poor, with 5-year survival rates as low as 25% for patients with limited-stage disease. Advances in therapy for small cell lung cancer have included the development of more effective chemotherapeutic agents and radiation techniques. For example, hyperfractionated radiotherapy given early in the course of the disease can reduce local recurrence and extend survival. Other technologic advances in radiation planning and delivery such as intensity-modulated radiotherapy, image-guided adaptive radiotherapy, and 4-dimensional computed tomography/positron emission tomography have facilitated the design of treatment volumes that closely conform to the shape of the tumor, which allows higher radiation doses to be given while minimizing radiation-induced toxicity to adjacent structures. Future improvements in outcomes will require clarifying the molecular basis for this disease.

Small cell lung cancer

Neuroendocrine tumors account for approximately 20% of lung cancers; most (≈15%) are small cell lung cancer (SCLC). These NCCN Clinical Practice Guidelines in Oncology for SCLC focus on extensive-stage SCLC because it occurs more frequently than limited-stage disease. SCLC is highly sensitive to initial therapy; however, most patients eventually die of recurrent disease. In patients with extensive-stage disease, chemotherapy alone can palliate symptoms and prolong survival in most patients; however, long-term survival is rare. Most cases of SCLC are attributable to cigarette smoking; therefore, smoking cessation should be strongly promoted.

Clinical applicability of staging small cell lung cancer according to the seventh edition of the TNM staging system

The two-stage system of limited and extensive disease has been widely employed for small cell lung cancer (SCLC). However, the International Association for the Study of Lung Cancer has proposed that the TNM classification should be incorporated into clinical practice. The purpose of this study was to evaluate the applicability of the Union for International Cancer Control (UICC) 7th TNM staging system to SCLC. We retrospectively reviewed the medical records of consecutive patients with newly diagnosed histologically proven SCLC between March 2005 and January 2010. Patients who had other concurrent malignancies or had combined-type SCLC were excluded. We assessed overall survival (OS) according to the T descriptor, N descriptor, M descriptor, and TNM stage grouping. In total, 320 SCLC patients were included. Median age was 65 years and 286 patients (89.4%) were male. Median OS was 12.7 months. There were no significant differences in OS according to the T descriptor (P = 0.880). However, there were significant differences in OS according to the N (P < 0.001) and M (P < 0.001) descriptors and TNM stage grouping (P < 0.001). Hazard ratios for OS, adjusted for known prognostic factors, differed significantly according to the N and M descriptor, and TNM stage grouping, but not according to the T descriptors. The UICC 7th TNM staging system may contribute to a more precise prognosis in SCLC patients. Further studies are required to evaluate the applicability of the TNM staging system to SCLC.

Impact of ERCC1 expression on treatment outcome in small-cell lung cancer patients treated with platinum-based chemotherapy

INTRODUCTION

The excision repair cross-complementing 1 (ERCC1) protein is an extensively investigated molecular marker because it may decrease sensitivity to platinum-based chemotherapy. Low ERCC1 expression has already been correlated with better treatment efficacy in non-small-cell lung cancer patients treated with platinum-based chemotherapy. However, the data on a prognostic and/or predictive value of ERCC1 in small-cell lung cancer (SCLC) are still very limited.

METHODS

This retrospective pilot study evaluated the impact of ERCC1 expression levels on response to first-line platinum-based chemotherapy with or without radiotherapy and survival outcomes of 77 SCLC patients. ERCC1 protein expression was determined immunohistochemically in primary tumour tissue.

RESULTS

ERCC1 protein expression was positive in 40/77 (51.9%) of our patients. No significant association was found between ERCC1 protein expression and response rate to first-line platinum-based chemotherapy, progression-free survival (PFS), or overall survival (OS), either in the overall population or in patients stratified by disease stage.

CONCLUSIONS

In our limited group of 77 SCLC patients, ERCC1 protein expression was not found to correlate with either response rate to platinum-based chemotherapy or survival outcomes. Multi-centric prospective trials using a validated method of ERCC1 determination are mandatory in order to obtain a definitive answer on the predictive value of ERCC1 in SCLC.

Specific organ metastases and survival in small cell lung cancer

The aim of our retrospective study was to evaluate the clinicopathological features associated with distant metastasis from small cell lung cancer (SCLC). We reviewed patients diagnosed with SCLC metastasis at the time of presentation between 1999 and 2010. Among the consecutive 251 SCLC patients diagnosed, 152 (60.6%) patients had distant metastasis, of which 20.3, 18.3, 15.5, 10.0 and 6.0% of patients had liver, bone, brain, lung and adrenal gland metastasis, respectively. In a multivariate analysis using Cox's proportional hazards model, we identified that liver, bone and brain metastasis as well as the presence of pleural and/or pericardial fluids were unfavorable prognostic factors. However, lung, adrenal gland and extrathoracic lymph node metastasis were not statistically significant prognostic factors. With regard to the treatment of SCLC patients, particularly those with liver, bone and brain metastasis or pleural and/or pericardial fluids, we should take the metastasizing organs into consideration.

Small-cell lung cancer

The incidence and mortality of small-cell lung cancer worldwide make this disease a notable health-care issue. Diagnosis relies on histology, with the use of immunohistochemical studies to confirm difficult cases. Typical patients are men older than 70 years who are current or past heavy smokers and who have pulmonary and cardiovascular comorbidities. Patients often present with rapid-onset symptoms due to local intrathoracic tumour growth, extrapulmonary distant spread, paraneoplastic syndromes, or a combination of these features. Staging aims ultimately to define disease as metastatic or non-metastatic. Combination chemotherapy, generally platinum-based plus etoposide or irinotecan, is the mainstay first-line treatment for metastatic small-cell lung cancer. For non-metastatic disease, evidence supports early concurrent thoracic radiotherapy. Prophylactic cranial irradiation should be considered for patients with or without metastases whose disease does not progress after induction chemotherapy and radiotherapy. Despite high initial response rates, most patients eventually relapse. Except for topotecan, few treatment options then remain. Signalling pathways have been identified that might yield new drug targets.

Prognostic role of integrin β1, E-cadherin, and rac1 expression in small cell lung cancer

Integrin β(1) mediates cellular adhesion to the extracellular matrix (ECM) and is correlated with highly invasive and metastatic behavior in small cell lung cancer (SCLC). E-cadherin (ECAD) is a calcium-dependent cell-cell adhesion receptor that restricts invasion of cells and reduces metastasis. Rac1 is involved in the regulation of the actin cytoskeleton, adhesion, migration, invasion, and tumor metastasis. The aim of this study was to examine integrin β(1) , ECAD and rac1 expression in SCLC and to analyze the prognostic value of these markers in patients with SCLC. We analyzed integrin β(1) , ECAD, and rac1 expression in 112 SCLC tissues by immunohistochemical staining. Correlative analyses between integrin β(1) , ECAD, and rac1 expression and cliniopathological factors were performed. A total of 65 patients had extensive disease (ED) (58%), and 47 had limited disease (LD) (42%). The median follow-up duration was 61 months (range: 14-117 months), and the median progression free survival (PFS) and overall survival (OS) were 6.1 months (range: 4.8-7.4 months) and 9.7 months (range: 8.1-11.3 months), respectively. The expression of integrin β(1) , ECAD, and rac1 protein was observed in 64, 73, and 99 of SCLC tissues, respectively. The correlative analyses between integrin β(1) , ECAD, or rac1 expression and various clinical parameters did not show any statistical significance. However, the ECAD expression was associated with OS in the entire cohort. In contrast, the expression of integrin β(1) and rac1 was not associated with PFS or OS. In a subgroup analysis, patients with less than two metastasis had significantly longer OS (p = 0.047) if their tumors expressed integrin β(1) compared to those without integrin β(1) expression. In addition, OS was longer for patients with ECAD positive tumors compared to those whose tumors did not express ECAD in males (p = 0.032) and patients who never smoked (p < 0.001). Multivariate analysis showed that LD (p = 0.004), overall response rate (p = 0.003), and expression of ECAD (p = 0.015) were the independent good prognostic factors for OS. LD (p = 0.024), overall response rate (p < 0.001), and less than two metastasis (p = 0.003) were prognostic factors for longer PFS. These results suggest that ECAD expression may be useful as a prognostic indicator in patients with SCLC.

Small-cell lung cancer: prognostic factors and changing treatment over 15 years

BACKGROUND

The incidence of small-cell lung cancer (SCLC) has decreased over several decades. Sixty-eight thousand six hundred eleven patients with SCLC in the National Cancer Data Base (NCDB) were analyzed to describe demographic, treatment, and survival changes between 1992 and 2007.

METHODS AND MATERIALS

Four patient cohorts-diagnosed in 1992, 1997, 2002, and 2007-were examined. Univariate and multivariate analyses were performed to determine changes in demographic and treatment factors and their effect on survival of limited SCLC (LSCLC) and extensive SCLC (ESCLC).

RESULTS

The proportion of female patients increased, whereas the proportion of non-Hispanic white patients decreased. Median survival for patients with ESCLC and LSCLC was 6.1 and 12.9 months, respectively, and was not significantly improved between patients diagnosed in 1992 and 2002. Improved survival was associated with female sex, age < 70 years, and receipt of surgery for patients with LSCLC. Radiation therapy decreased the hazard ratio (HR) for patients with stage III LSCLC but not for patients with earlier stage disease. Chemotherapy decreased the HR for all patients with LSCLC. Patients with ESCLC treated with radiation in addition to chemotherapy had better survival than those who received only chemotherapy.

CONCLUSIONS

Despite changes in demographics and treatment, the median and 5-year survival rates for patients with SCLC have not significantly improved over the past 15 years. Surgery was associated with improved survival in LSCLC. The benefit of chemotherapy and/or radiation therapy was dependent on American Joint Committee on Cancer (AJCC) stage. AJCC staging information had prognostic and treatment ramifications and should be collected in future studies and databases.

Neuroendocrine carcinoma of unknown primary: a systematic review of the literature and a comparative study with other neuroendocrine tumors

INTRODUCTION

Neuroendocrine carcinomas of unknown primary (NCUP) represent a specific subset with relatively favorable prognosis. Data on biology, management and outcome of NCUP patients have not been systematically reviewed neither compared to those of neuroendocrine tumors of known primary.

PATIENTS AND METHODS

We systematically reviewed all publications studying neuroendocrine CUP patients and presented a single center retrospective patient series. In addition, we analyzed and specified the similarities and/or differences between NCUP and other neuroendocrine malignancies.

RESULTS

Five hundred patients with NCUP constituted a heterogeneous cohort in terms of histology, grade, anatomic site and tumor biology in published series and were managed mostly with platinum-based regimens. Among 294 patients with available outcome data, a median survival of 15.5 months (range 11.6-40) was observed. Comparative analysis with neuroendocrine solid tumors (NET) revealed that poorly-differentiated NCUP share an aggressive natural history and a dismal prognosis similar to high grade pulmonary and extrapulmonary neuroendocrine carcinomas (Large Cell Neuroendocrine bronchial Carcinomas, LCNEC and poorly differentiated gastroenteropancreatic tumors, GEP-NET). Well differentiated NCUP reveal a more indolent course with a survival range resembling that of typical and atypical pulmonary carcinoids, well differentiated gastrointestinal NETs and limited small cell lung carcinomas.

CONCLUSION

No evidence for distinct biology or outcome of NCUP patients emerged when histological grade was matched for known primary NETs. The high heterogeneity of the NCUP subgroup limits the potential for identification of reliable prognosticators and hinders development of novel targeted therapies.

Predictive value of multidrug resistance proteins, topoisomerases II and ERCC1 in small cell lung cancer: a systematic review

In small-cell lung cancer (SCLC), resistance to cancer drugs presents a major problem, limiting the effectiveness of chemotherapy. A better understanding of the molecular biology is essential to improve currently available cytotoxic therapy. Herein, a systematic review of studies evaluating the predictive value of multidrug resistance-associated proteins (MDR1, MRP1, MRP2 and MVP), topoisomerase II and ERCC1 for chemotherapy outcomes is presented. The role of MDR1, MRP1 and MRP2 as predictive markers in SCLC has not yet been elucidated. The majority of studies reported an association between protein or gene expression and response to chemotherapy; however, the evidence is limited to univariate analyses performed in the frame of small retrospective trials. In addition, the largest trial did not confirm an independent predictive value for response rates or survival. Genetic variability may be overseen as a more promising marker. Available data on the predictive value of topoisomerase II are scarce and in contrast to the general idea that higher protein or gene expression correlate with greater chemo-sensitivity. The data on a possible predictive value of ERCC1 are also quite limited; in two retrospective studies, ERCC1 turned out to be a significant predictive marker for survival, but only for limited disease patients. In conclusion, a continuous research, with standardized and validated methodology of markers' determination, should be aspired at all times; a better understanding of the biology of SCLC is of utmost importance to enable personalized therapy and to improve survival rates in this, so far, poorly controlled disease.

Tumor response and progression-free survival as potential surrogate endpoints for overall survival in extensive stage small-cell lung cancer: findings on the basis of North Central Cancer Treatment Group trials

BACKGROUND

The authors investigated the putative surrogate endpoints of best response, complete response (CR), confirmed response, and progression-free survival (PFS) for associations with overall survival (OS), and as possible surrogate endpoints for OS.

METHODS

Individual patient data from 870 untreated extensive stage small-cell lung cancer patients participating in 6 single-arm (274 patients) and 3 randomized trials (596 patients) were pooled. Patient-level associations between putative surrogate endpoints and OS were assessed by Cox models using landmark analyses. Trial-level surrogacy of putative surrogate endpoints were assessed by the association of treatment effects on OS and individual putative surrogate endpoints. Trial-level surrogacy measures included: R(2) from weighted least squares regression model, Spearman correlation coefficient, and R(2) from bivariate survival model (Copula R(2) ).

RESULTS

Median OS and PFS were 9.6 (95% confidence interval [CI], 9.1-10.0) and 5.5 (95% CI, 5.2-5.9) months, respectively; best response, CR, and confirmed response rates were 44%, 22%, and 34%, respectively. Patient-level associations showed that PFS status at 4 months was a strong predictor of subsequent survival (hazard ratio [HR], 0.42; 95% CI, 0.35-0.51; concordance index 0.63; P < .01), with 6-month PFS being the strongest (HR, 0.41; 95% CI, 0.35-0.49; concordance index, 0.66, P < .01). At the trial level, PFS showed the highest level of surrogacy for OS (weighted least squares R(2) = 0.79; Copula R(2) = 0.80), explaining 79% of the variance in OS. Tumor response endpoints showed lower surrogacy levels (weighted least squares R(2) ≤0.48).

CONCLUSIONS

PFS was strongly associated with OS at both the patient and trial levels. PFS also shows promise as a potential surrogate for OS, but further validation is needed using data from a larger number of randomized phase 3 trials.

Biostatistics: a toolkit for exploration, validation, and interpretation of clinical data

Biostatistics plays a key role in all phases of clinical research starting from the design to the monitoring, data collection, data analysis, and interpretation of the results. A clear understanding of the statistical framework as it relates to the study hypothesis, reported results, and interpretation is vital for the scientific integrity of the study and its acceptance in the general medical community. In this brief report, we will put in perspective the general analytical framework for exploring and validating prognostic factors using data from large databases.