Serum biomarkers of non-neuron-endocrine origin in small-cell lung cancer: a 16-year study on carcinoembryonic antigen, tissue polypeptide antigen and lactate dehydrogenase

Are pretreatment neutrophil-lymphocyte ratio and platelet-lymphocyte ratio useful in predicting the outcomes of patients with small-cell lung cancer?

OBJECTIVES

The neutrophil-lymphocyte ratio (NLR) and the platelet-lymphocyte ratio (PLR) have been proved to affect the prognosis of various types of cancers. However, the prognostic role of NLR and PLR in patients with small-cell lung cancer (SCLC) remains controversial. The objective of this study is to assess the prognostic values of NLR, PLR and other potential prognostic indexes in SCLC patients.

RESULTS

The optimal cutoff levels were 2.65 for NLR, 125 for PLR and 210 for LDH by ROC curves analysis. Patients in the NLR ≥ 2.65 and LDH ≥ 210 groups were significantly correlated with worse PFS and OS. However, patients in the PLR < 125 group presented longer PFS time than patients in the PLR ≥ 125 group. Multivariate analysis showed that NLR ≥ 2.65 was an independent risk factor for both PFS (HR = 1.38; 95% CI 1.04-1.83; P = 0.027) and OS (HR = 1.35; 95% CI 1.02-1.79; P = 0.039). LDH and the clinical stage were independent prognostic factors for PFS in SCLC patients. LDH, surgery history, thoracic RT and PCI were independent prognostic factors for OS.

MATERIALS AND METHODS

320 patients with SCLC were enrolled in this research from 2007 to 2014. Data was acquired through patients' medical records and follow-ups. Receiver operating curve (ROC) was used to determine the optimal cut-off levels of NLR, PLR and lactate dehydrogenase (LDH). The Kaplan-Meier univariate analysis and multivariate Cox regression analysis were used to evaluate the impact of the NLR, PLR and other potential prognostic factors on overall survival (OS) and progressive-free survival (PFS).

CONCLUSIONS

Pretreatment elevated NLR and LDH were independent factors for poor prognosis in SCLC patients. High PLR was associated with poor PFS, but it was not an independent prognostic factor for PFS and OS.

Serum markers in small cell lung cancer: opportunities for improvement

Lung cancer is one of the leading causes of death from malignancy worldwide. In particular small cell lung cancers, which comprise about 15-20% of all lung cancers, are extremely aggressive and cure rates are extremely low. Therefore, new treatment modalities are needed and detection at an early stage of disease, as well as adequate monitoring of treatment response is essential in order to improve outcome. In this respect, the use of non-invasive tools for screening and monitoring has gained increasing interest and the clinical applicability of reliable, tumor-related substances that can be detected as tumor markers in easily accessible body fluids is subject of intense investigation. Some of these indicators, such as high LDH levels in serum as a reflection of the disease, have been in use for a long time as a general tumor marker. To allow for improved monitoring of the efficacy of new therapeutic modalities and for accurate subtyping, there is a strong need for specific and sensitive markers that are more directly related to the biology and behavior of small cell lung cancer. In this review the current status of these potential markers, like CEA, NSE, ProGRP, CK-BB, SCC, CgA, NCAM and several cytokeratins will be critically analyzed with respect to their performance in blood based assays. Based on known cleavage sites for cytoplasmic and extracellular proteases, a prediction of stable fragments can be obtained and used for optimal test design. Furthermore, insight into the synthesis of specific splice variants and neo-epitopes resulting from protein modification and cleavage, offers further opportunities for improvement of tumor assays. Finally, we discuss the possibility that detection of SCLC related autoantibodies in paraneoplastic disease can be used as a very early indicator of SCLC.

Elevated serum C-reactive protein as a prognostic marker in small cell lung cancer

PURPOSE

Elevated C-reactive protein (CRP) is associated with poor prognosis in several tumor types. The purpose of this study was to investigate serum CRP as a prognostic marker in small cell lung cancer (SCLC).

MATERIALS AND METHODS

The pretreatment serum CRP level was measured in 157 newly diagnosed SCLC patients, and correlation between serum CRP level and other clinical parameters was analyzed. Multivariate analyses were performed to find prognostic markers using Cox's proportional hazards model.

RESULTS

The initial CRP concentration was within the normal range in 72 (45.9%) patients and elevated in 85 (54.1%) patients. There was a significant correlation between serum CRP level and the extent of disease (p<0.001), weight loss (p=0.029) and chest radiation (p=0.001). Median overall survival (OS) in the normal CRP group was significantly longer than with the high CRP group (22.5 months vs. 11.2 months, p<0.001). Extent of disease (p<0.001), age (p=0.025), and performance status (p<0.001) were additional prognostic factors on univariate analysis. On multivariate analysis, elevated serum CRP level was an independent prognostic factor for poor survival (HR=1.8; p=0.014), regardless of the extent of disease (HR=3.7; p<0.001) and performance status (HR=2.2; p<0.001).

CONCLUSION

High level of CRP was an independent poor prognostic serum marker in addition to previously well-known prognosticators in patients with SCLC.

Evaluation of circulating tumor cells and serological cell death biomarkers in small cell lung cancer patients undergoing chemotherapy

Serological cell death biomarkers and circulating tumor cells (CTCs) have potential uses as tools for pharmacodynamic blood-based assays and their subsequent application to early clinical trials. In this study, we evaluated both the expression and clinical significance of CTCs and serological cell death biomarkers in patients with small cell lung cancer. Blood samples from 88 patients were assayed using enzyme-linked immunosorbent assays for various cytokeratin 18 products (eg, M65, cell death, M30, and apoptosis) as well as nucleosomal DNA. CTCs (per 7.5 ml of blood) were quantified using Veridex CellSearch technology. Before therapeutic treatment, cell death biomarkers were elevated in patients compared with controls. CTCs were detected in 86% of patients; additionally, CD56 was detectable in CTCs, confirming their neoplastic origin. M30 levels correlated with the percentage of apoptotic CTCs. M30, M65, lactate dehydrogenase, and CTC number were prognostic for patient survival as determined by univariate analysis. Using multivariate analysis, both lactate dehydrogenase and M65 levels remained significant. CTC number fell following chemotherapy, whereas levels of serological cell death biomarkers peaked at 48 hours and fell by day 22, mirroring the tumor response. A 48-hour rise in nucleosomal DNA and M30 levels was associated with early response and severe toxicity, respectively. Our results provide a rationale to include the use of serological biomarkers and CTCs in early clinical trials of new agents for small cell lung cancer.

Biomarkers in drug discovery and development: from target identification through drug marketing

Biomarkers of disease play an important role in medicine and have begun to assume a greater role in drug discovery and development. The challenge for biomarkers is to allow earlier, more robust drug safety and efficacy measurements. Their role in drug development will continue to grow for the foreseeable future. For biomarkers to assume their rightful role, greater understanding of the mechanism of disease progression and therapeutic intervention is needed. In addition, greater understanding of the requirements for biomarker selection and validation, biomarker assay method validation and application, and clinical endpoint validation and application is needed. Biomarkers need to be taken into account while the therapeutic target is still being identified and the concept is being formulated. Biomarkers need to be incorporated into a continuous cycle that takes what is learned from the discovery and development of one series of biomarkers and translates it into the next series of biomarkers. Optimum biomarker development and application will require a team approach because of the multifaceted nature of biomarker selection, validation, and application, using such techniques as pharmacoepidemiology, pharmacogenetics, pharmacogenomics, and functional proteomics; bioanalytical method development and validation; disease process and therapeutic intervention assessments; and pharmacokinetic/pharmacodynamic modeling and simulation to improve and refine drug development. The potential for biomarkers in medicine and drug development will be limited by the least effective component of the processes. The team approach will minimize the potential for the least effective component to be fatal to the rest of the process. As scientific/regulatory foundations for biomarkers in medicine and drug development begin to be established, successes and applications will need to be effectively communicated with all of the stakeholders, including not only internal and external drug developers and regulators but also the medical community, to ensure that biomarkers are totally integrated into drug discovery and development as well as the practice of medicine.

Identifying patients at risk of early postoperative recurrence of lung cancer: a new use of the old CEA test

BACKGROUND

In the current study, we report the carcinoembryonic antigen (CEA) capability to predict early tumor relapses after a pulmonary resection for nonsmall cell lung cancer (NSCLC).

METHODS

We studied 118 consecutive NSCLC patients who were clinically judged operable and were eventually operated upon. Anthropometric, clinical, and CEA data along with the results of both preoperative and postoperative stage classifications were recorded. All patients were followed up for at least 1 year after surgery and the time to the first clinical recurrence recorded. Receiver-operating characteristic (ROC) curves and diagnostic formulas were used for data analysis.

RESULTS

In this series the CEA test was among the most accurate methods to predict an early postoperative recurrence (ROC area: 0.72, 95% confidence interval [CI]: 0.60 to 0.85, p = 0.001; accuracy rate for CEA at the threshold of 10 ng/mL: 83%, CI: 76% to 90%). Also predictive was the postoperative pathologic stage of disease (ROC area: 0.68, CI: 0.56 to 0.80, p = 0.007). In tumors pathologically classified in stage Ia to IIb, a preoperative CEA level higher than 10 ng/mL was associated with a 67% probability of tumor relapse. In the same stages of disease, a CEA level less than 10 ng/mL increased the baseline probability of no recurrence from 80% to 88%.

CONCLUSIONS

In operable patients with NSCLC the frequency of abnormal serum concentrations of CEA is low (17% in our series). However, it is important to identify such a small group of high-risk patients as many of them (in our study, 55% and 70% of those with a CEA value in excess of, respectively, 5 and 10 ng/mL) will develop an early postoperative recurrence. Such patients should be investigated preoperatively by mediastinoscopy or positron emission tomography in even in the absence of suspicious symptoms and signs. Then after an apparently successful operation, they should be carefully followed up. These patients could represent a suitable target for neoadjuvant clinical trials of selected high-risk groups.