Assessment of SHOX2 methylation in EBUS-TBNA specimen improves accuracy in lung cancer staging

BACKGROUND

Endobronchial ultrasound with transbronchial needle aspiration (EBUS-TBNA) is a well-established method to assess mediastinal lymph nodes for lung cancer. However, a proportion of patients require further investigation, due to the low negative predictive value (NPV). The objective of this study was to determine whether the assessment of short stature homeobox 2 (SHOX2) DNA methylation level in lymph node tissue obtained by EBUS-TBNA improves the accuracy of mediastinal staging.

PATIENTS AND METHODS

EBUS-TBNA was carried out for suspicious lymph nodes of 154 patients. Negative or ambiguous histological results were confirmed by surgical means and clinical follow-up over 6 months. EBUS-TBNA was assessed on 80 positive and 85 negative classified lymph nodes and compared with the result of the SHOX2 DNA methylation real-time PCR analysis. Relative methylation measured by delta-delta cycle threshold (ΔΔCt) was used to classify the samples. Clinical performance of the EBUS-TBNA procedure with and without the additional SHOX2 assessment was calculated against the final classification according to the gold standard.

RESULTS

Based on data from 105 patients, an average 80-fold increase in the SHOX2 methylation level was measured for positive compared with negative lymph nodes. SHOX2 results with a ΔΔCt value of <6.5 indicate positive lymph nodes. Applying this molecular analysis to EBUS-TBNA cases, not diagnosed by pathologic assessment, the sensitivity of staging was improved by 17%-99%. The NPV increased from 80% to 99%.

CONCLUSIONS

The combination of EBUS-TBNA and SHOX2 methylation level strongly improves the assessment of the nodal status by identifying additional malignant lesions and confirming benign nodes and therefore avoiding invasive follow-up procedures.

[German guideline for diagnosis and management of idiopathic pulmonary fibrosis]

Idiopathic pulmonary fibrosis is a fatal lung disease with a variable and unpredictable natural history and limited treatment options. Since publication of the ATS-ERS statement on IPF in the year 2000 diagnostic standards have improved and a considerable number of randomized controlled treatment trials have been published necessitating a revision. In the years 2006 - 2010 an international panel of IPF experts produced an evidence-based guideline on diagnosis and treatment of IPF, which was published in 2011. In order to implement this evidence-based guideline into the German Health System a group of German IPF experts translated and commented the international guideline, also including new publications in the field. A consensus conference was held in Bochum on December 3rd 2011 under the protectorate of the "Deutsche Gesellschaft für Pneumologie und Beatmungsmedizin (DGP)" and supervised by the "Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften" (AWMF). Most recommendations of the international guideline were found to be appropriate for the german situation. Based on recent clinical studies "weak negative" treatment recommendations for pirfenidone and anticoagulation were changed into "weak positive" for pirfenidone and "strong negative" for anticoagulation. Based on negative results from the PANTHER-trial the recommendation for the combination therapy of prednisone plus azathiorpine plus N-acetlycsteine was also changed into strong negative für patients with definite IPF. This document summarizes essential parts of the international IPF guideline and the comments and recommendations of the German IPF consensus conference.

Diagnostic approach to interstitial pneumonias in a single centre: report on 88 cases

Background

Interstitial pneumonias (IP) cover a broad spectrum of diseases. Open lung biopsies reveal histological patterns and suggest possible diagnoses. Complete clinical records are necessary for final diagnoses. Especially idiopathic interstitial pneumonias (IIP) according to the ATS/ERS classification can only be diagnosed under these predictions. The aim of this study was to compare the results of histological evaluations with the final diagnosis after interdisciplinary case evaluation.

Patients and methods

88 patients with interstitial pneumonia that underwent open lung biopsies were investigated. Histology and clinical records were available for review. Diagnosis was made in three steps: first on the sole basis of histology, second with clinical information given initially and third, on the basis of an interdisciplinary case evaluation.

Results

63 patients (72%) were diagnosed as idiopathic interstitial pneumonias according to ATS/ERS criteria. Further 10 (11%) cases of hypersensitivity pneumonitis, 7 (8%) Langerhans cell histiocytosis and 8 (9%) interstitial pneumonias of other known causes or associations were detected. Histological patterns alone agreed with the final diagnosis in 67%. In 82% histology and clinical information given to the pathologist could provide correct diagnosis. In the rest of cases, especially in non idiopathic interstitial pneumonias, an interdisciplinary case evaluation was needed.

Conclusions

Diagnosis of interstitial pneumonias by open lung biopsies needs sufficient clinical information. Because of the overlap of histological patterns, an interdisciplinary case evaluation that includes at least one clinical expert and one pathologist with excellent expertise and the follow-up of the patients is necessary to find correct diagnosis in all cases.

Virtual slides

The virtual slides for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/5031706258025129

βV-tubulin expression is associated with outcome following taxane-based chemotherapy in non-small cell lung cancer

Background:

Tubulin-binding agents (TBAs) are effective in non-small cell lung cancer (NSCLC) treatment. Both βIII- and βV-tubulins are expressed by cancer cells and may lead to resistance against TBAs.

Methods:

Pre-treatment samples from 65 locally advanced or oligometastatic NSCLC patients, who underwent uniform induction chemotherapy with paclitaxel and platinum followed by radiochemotherapy with vinorelbine and platinum were retrospectively analysed by immunohistochemistry. Protein expression of βIII- and βV-tubulin was morphometrically quantified.

Results:

Median pre-treatment H-score for βIII-tubulin was 110 (range: 0–290), and 160 for βV-tubulin (range: 0–290). Low βIII-tubulin expression was associated with improved overall survival (OS) (P=0.0127, hazard ratio (HR): 0.328). An association between high βV-tubulin expression and prolonged progression-free survival (PFS, median 19.2 vs 9.4 months in high vs low expressors; P=0.0315, HR: 1.899) was found. Further, high βV-tubulin expression was associated with objective response (median H-score 172.5 for CR+PR vs 120 for SD+PD patients, P=0.0104) or disease control following induction chemotherapy (170 for CR+PR+SD vs 100 for PD patients, P=0.0081), but not radiochemotherapy.

Conclusion:

Expression of βV-tubulin was associated with treatment response and PFS following paclitaxel-based chemotherapy of locally advanced and oligometastatic NSCLC patients. Prolonged OS was associated with low levels of βIII-tubulin. Prospective evaluation of βIII/βV-tubulin expression in NSCLC is warranted.

Abstract 1713: Folylpoly-α-glutamate synthetase and thymidylate synthase are associated with clinical outcome from pemetrexed-based therapy in advanced non-small cell lung cancer (NSCLC)

Background: The antifolate pemetrexed targets multiple enzymes involved in pyrimidine and purine synthesis including thymidylate synthase (TS). After entry into cells, pemetrexed is converted to polyglutamated forms by folylpoly-α-glutamate synthetase (FPGS), a critical step to achieve full target inhibition. We hypothesized that FPGS and TS protein expression may predict outcome following pemetrexed-treatment of patients with advanced NSCLC, like in malignant pleural mesotheliomas (Christoph et al., J Clin Oncol. 2011: 29 suppl.). This is the largest report on pemetrexed-treatment outcome based on TS and FPGS in Caucasian patients with advanced NSCLC. Methods: Pretreatment tumor samples from 161 patients (pts) with metastatic NSCLC, treated with PMX (82 pts (51%)), a combination of PMX with platinum (74 pts (46%)) or within other combinations (5 pts (3%)), were retrospectively analyzed. FPGS and TS protein expression levels were evaluated by IHC using the H-Scoring system (0-300), which relies on the product of intensity (range 0 to 3) and the percentage of positive tumor cells (0-100%). Radiographic evaluation of response was performed according to RECIST criteria (version 1.1). Results: Median pretreatment H-scores were 180 for FPGS (range: 0-280) and 205 (range: 120-290) for TS. Using the log-rank test and the median H-score as cut-off, we found a significant association between low TS protein expression and improved progression-free survival (PFS) (median PFS of 5.5 months vs 3.4 months; hazard ratio [HR] 0.66, 95% CI, 0.45 to 0.96; P=0.03) or prolonged overall survival (median OS of 33.9 months vs 15.0 months; hazard ratio [HR] 0.52, 95% CI, 0.31 to 0.86; P=0.01). Moreover, high FPGS protein expression was only associated with better PFS (median PFS of 5.5 months vs 3.4 months; hazard ratio [HR] 0.58, 95% CI, 0.37 to 0.89; P=0.03). Considering exclusively patients suffering from adenocarcinomas (110 pts (68%)), TS was associated with objective response to pemetrexed-based treatment (mean H-score 192 for responders vs 210 for non-responders, P=0.03). Conclusions: We have investigated FPGS and TS protein expressions in tumor specimens from the largest series of PMX-treated Caucasian NSCLC patients. Baseline determination of TS and FPGS expression by IHC using the H-score system is associated with clinical outcome from PMX-based therapy in advanced NSCLC. Further prospective validation studies are warranted.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1713. doi:1538-7445.AM2012-1713

Abstract B6: Folylpoly-glutamate synthetase and thymidylate synthase are associated with clinical outcome from pemetrexed-based therapy in non-small cell lung cancer (NSCLC)

Background: The antifolate pemetrexed targets multiple enzymes involved in pyrimidine and purine synthesis including thymidylate synthase (TS). After entry into cells, pemetrexed is converted to polyglutamated forms by folylpoly-γ-glutamate synthetase (FPGS), a critical step to achieve full target inhibition. We hypothesized that FPGS and TS protein expression may predict outcome following pemetrexed-treatment of patients with advanced NSCLC, like in malignant pleural mesotheliomas (Christoph et al., J Clin Oncol. 2011: 29 suppl.). This is the largest report on pemetrexed-treatment outcome based on TS and FPGS in Caucasian patients with advanced NSCLC.

Methods: Pretreatment tumor samples from 161 patients (pts) with metastatic NSCLC, treated with pemetrexed combined with platinum (74 pts (46%)) or as single agent (82 pts (51%)) or within other combinations (5 pts (3%)), were retrospectively analyzed. FPGS and TS protein expression levels were evaluated by IHC using the H-Scoring system (0–300), which relies on the product of intensity (range 0 to 3) and the percentage of positive tumor cells (0–100%). Radiographic evaluation of response was performed according to RECIST criteria (version 1.1).

Results: Median pretreatment H-scores were 180 for FPGS (range: 0–280) and 205 (range: 120–290) for TS. Using the log-rank test and the median H-score as cut-off, we found a significant association between low TS protein expression and improved progression-free survival (PFS) (median PFS of 5.5 months vs. 3.4 months; hazard ratio [HR] 0.66, 95% CI, 0.45 to 0.96; P=0.03) or prolonged overall survival (median OS of 33.9 months vs. 15.0 months; hazard ratio [HR] 0.52, 95% CI, 0.31 to 0.86; P=0.01). Moreover, high FPGS protein expression was only associated with better PFS (median PFS of 5.5 months vs. 3.4 months; hazard ratio [HR] 0.58, 95% CI, 0.37 to 0.89; P=0.03). Considering exclusively patients suffering from adenocarcinomas (110 pts (68%)), TS was associated with objective response to pemetrexed-based treatment (mean H-score 192 for responders vs. 210 for non-responders, P=0.03).

Conclusions: We have investigated FPGS and TS protein expressions in tumor specimens from the largest series of pemetrexed-treated Caucasian NSCLC patients. Baseline determination of TS and FPGS expression by IHC using the H-score system is associated with clinical outcome from pemetrexed-based therapy in advanced NSCLC. Further prospective validation studies are warranted.