Epidermal growth factor receptor overexpression in malignant pleural mesothelioma: prognostic correlations

BACKGROUND

To evaluate epidermal growth factor receptor (EGFR) phenotypic expression and related gene status in malignant pleural mesothelioma (MPM) and to correlate the results with patients' prognosis.

METHOD

Eighty-three cases of MPM specimens were submitted to immunohistochemical (IHC) staining to evaluate the expression of EGFR protein; positive cases were submitted to fluorescence in situ hybridization (FISH) to investigate the gene status. Results were correlated with clinico-pathological characteristics and long-term survival.

RESULTS

Thirty-eight cases (46%) demonstrated a positive IHC reaction [30/57 (52%) epithelial and 8/20 (40%) biphasic whereas sarcomatous MPM were negative]. No association was recorded between EGFR IHC positive staining and age, gender, or asbestos exposure. Three out of 38 (8%) cases submitted to FISH were positive revealing gene amplification or polysomy. Mean follow-up was 15.4  months (range 2-44). Epithelial subtype only was confirmed to affect prognosis (2-years survival rate 40 vs. 18% for non-epithelial subtype, P = 0.042). When epithelial MPM patients were considered, IHC EGFR positive staining was demonstrated to be a negative prognostic factor (2-years survival rate 26 vs. 60% for IHC EGFR negative staining; P = 0.026).

CONCLUSIONS

EGFR overexpression is identified by IHC in 52% of epithelial MPM and is demonstrated to be a factor negatively affecting prognosis. Phenotypic overexpression seems not to be related to gene status alteration.

XRCC1 and ERCC1 variants modify malignant mesothelioma risk: a case-control study

Malignant pleural mesothelioma (MPM) is a rare aggressive tumor associated with asbestos exposure. The possible role of genetic factors has also been suggested and MPM has been associated with single nucleotide polymorphisms (SNPs) of xenobiotic and oxidative metabolism enzymes. We have identified an association of the DNA repair gene XRCC1 with MPM in the population of Casale Monferrato, a town exposed to high asbestos pollution. To extend this observation we examined 35 SNPs in 15 genes that could be involved in MPM carcinogenicity in 220 MPM patients and 296 controls from two case-control studies conducted in Casale (151 patients, 252 controls) and Turin (69 patients, 44 controls), respectively. Unconditional multivariate logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs). Two DNA repair genes were associated with MPM, i.e. XRCC1 and ERCC1. Considering asbestos-exposed only, the risk increased with the increasing number of XRCC1-399Q alleles (Casale: OR=1.44, 95%CI 1.02-2.03; Casale+Turin: OR=1.34, 95%CI 0.98-1.84) or XRCC1 -77T alleles (Casale+Turin: OR=1.33, 95%CI 0.97-1.81). The XRCC1-TGGGGGAACAGA haplotype was significantly associated with MPM (Casale: OR=1.76, 95%CI 1.04-2.96). Patients heterozygotes for ERCC1 N118N showed an increased OR in all subjects (OR=1.66, 95%CI 1.06-2.60) and in asbestos-exposed only (OR=1.59, 95%CI 1.01-2.50). When the dominant model was considered (i.e. ERCC1 heterozygotes CT plus homozygotes CC versus homozygotes TT) the risk was statistically significant both in all subjects (OR=1.61, 95%CI 1.06-2.47) and in asbestos-exposed only (OR=1.56, 95%CI 1.02-2.40). The combination of ERCC1 N118N and XRCC1 R399Q was statistically significant (Casale: OR=2.02, 95%CI 1.01-4.05; Casale+Turin: OR=2.39, 95%CI 1.29-4.43). The association of MPM with DNA repair genes support the hypothesis that an increased susceptibility to DNA damage may favour asbestos carcinogenicity.

Role of diffusion-weighted imaging in the differential diagnosis of benign and malignant lesions of the chest-mediastinum

PURPOSE

We retrospectively evaluated the role of diffusion-weighted imaging (DWI) with fat and background signal suppression in the differential diagnosis of benign and malignant lesions of the chest-mediastinum by calculating the mean apparent diffusion coefficient (ADC) values.

MATERIALS AND METHODS

Thirty-four patients with lung nodules/mediastinal masses underwent magnetic resonance (MR) imaging of the chest with conventional and DWI sequences. All patients had been previously studied with computed tomography (CT). After magnetic resonance (MR) imaging the patients underwent transthoracic CT-guided biopsy or mediastinoscopy. After the histopathological diagnosis had been obtained, the lesions were retrospectively divided into five groups: adenocarcinomas (n=16), squamous cell carcinomas (n=12), chronic pneumonias (n=2), malignant mediastinal tumours (n=2) and typical carcinoids (n=2). We compared ADC values in the different lesion groups using the Mann-Whitney U test.

RESULTS

There were statistically significant differences (p<0.05) between ADC values of benign and malignant lesions. Using an ADC value of 1.25×10⁻³ mm²/s as a threshold, we were able to differentiate malignant from benign lesions with 91% diagnostic accuracy, 90% sensitivity, 100% specificity, 100% positive predictive value and 57% negative predictive value.

CONCLUSIONS

Short-tau inversion-recovery echo-planar imaging (STIR-EPI) sequences applied to the chest-mediastinum provided potentially useful images for the differential diagnosis of benign and malignant lesions.

Mechanisms of gas exchange response to lung volume reduction surgery in severe emphysema

Lung volume reduction surgery (LVRS) improves lung function, respiratory symptoms, and exercise tolerance in selected patients with chronic obstructive pulmonary disease, who have heterogeneous emphysema. However, the reported effects of LVRS on gas exchange are variable, even when lung function is improved. To clarify how LVRS affects gas exchange in chronic obstructive pulmonary disease, 23 patients were studied before LVRS, 14 of whom were again studied afterwards. We performed measurements of lung mechanics, pulmonary hemodynamics, and ventilation-perfusion (Va/Q) inequality using the multiple inert-gas elimination technique. LVRS improved arterial Po₂ (Pa(O₂)) by a mean of 6 Torr (P = 0.04), with no significant effect on arterial Pco₂ (Pa(CO₂)), but with great variability in both. Lung mechanical properties improved considerably more than did gas exchange. Post-LVRS Pa(O₂) depended mostly on its pre-LVRS value, whereas improvement in Pa(O(2)) was explained mostly by improved Va/Q inequality, with lesser contributions from both increased ventilation and higher mixed venous Po(2). However, no index of lung mechanical properties correlated with Pa(O₂). Conversely, post-LVRS Pa(CO₂) bore no relationship to its pre-LVRS value, whereas changes in Pa(CO₂) were tightly related (r² = 0.96) to variables, reflecting decrease in static lung hyperinflation (intrinsic positive end-expiratory pressure and residual volume/total lung capacity) and increase in airflow potential (tidal volume and maximal inspiratory pressure), but not to Va/Q distribution changes. Individual gas exchange responses to LVRS vary greatly, but can be explained by changes in combinations of determining variables that are different for oxygen and carbon dioxide.

Abstract P3-02-13: Is HER2 Evaluation with the CellSearch System a Method Reliable for Detecting HER2 Overexpression?

Background. Circulating tumor cells (CTCs) detected in patients with both localized and metastatic breast cancer are significantly associated with a worse outcome. In addition to enumeration, an exciting area of CTC research involves the phenotyping and expression profiling of CTCs. In this regard, in patients with metastatic breast cancer, the evaluation of CTCs could be considered as a “real-time” biopsy allowing the detection of possible changes in tumor phenotype, such as a shift in patients HER2- negative on the primary tumor to HER2-positive CTCs. This could be of relevance as these patients may become suitable to targeted anti-HER2 therapy. Currently, there is no standardized and widely accepted method available for the determination of HER2 status on CTC. Aims. Objectives of this study were: 1. verifying the feasibility and reliability of HER2 determination on cells from scraping of breast cancer tissue by FISH analysis, 2. evaluating the concordance of HER2 status determined on primary breast tumor by immunohistochemistry (IHC) and on scraped cells, obtained from the same breast tumor and spiked in blood from healthy subjects, using the CellSearch System, and finally 3. evaluating the concordance of HER2 expression determinated by FISH analysis and by CellSearch on the same scraped cells. Methods. Cells from scraping of fresh breast cancer tissues with different level of HER2 expression were spiked in 18 healthy subjects blood samples. The determination of the HER2 expression on these cells was performed with the CellSearch System (Veridex, USA) by the addition of a fluorescein conjugated monoclonal antibody to be used in conjunction with the CellSearch™ Epithelial Cell Kit to phenotype CTCs for the presence of HER-2/neu. The HER2 characterisation of the primary breast tumors was performed by IHC by FISH analysis according to standard procedures. FISH was also performed on cells from scraping of fresh breast cancer tissues after CellSearch enumeration and characterization, by removing them from the “MagNest” cartridge. Tumors with a score of 3+ were considered positive.

Results. The results of the FISH analysis performed on the cells aspirated from the cartridge demonstrated a 100% concordance with the FISH performed on fresh tissue (9 not amplified and 9 amplified). The evaluation of HER2 expression on scraped cells by CellSearch System and by IHC on the corresponding tumor showed that the CellSearch method is reliable in identifying HER2 overexpression, as in all the 3+ tumors it was possible to detect variable percentage of scraped cells overexpressing HER2. Finally, different number of HER2+ scraped cells were found in 16 out of the 18 samples: the only 2 negative samples were both IHC negative and FISH not amplified. On the contrary 2 of the 4 remaining negative/1+ IHC samples, showed some scraped cells HER2+ which resulted FISH amplified. Conclusion. This study demonstrates that FISH analysis is feasible and the results are reliable when performed on cells after CellSearch procedure. Moreover HER2 expression may be evaluated with the CellSearch System and it may be used as a preliminary method to indicate possibly HER2 positive samples which may be confirmed by FISH analysis.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P3-02-13.

World Health Organization classification of thymomas provides significant prognostic information for selected stage III patients: evidence from an international thymoma study group

Information regarding prognosis of thymoma patients stratified by both World Health Organization classification and Masaoka staging system is very limited. Analyze 5-year survival data from a large number of thymoma patients stratified by both World Health Organization histologic type and Masaoka stage using meta-analysis. Perform power analysis to estimate the number of cases that would be needed to test the null hypothesis to a power of 80%. Five-year survival data from 905 thymoma patients treated with thymectomy at seven hospitals in America, Japan, Korea, India, Italy, and Germany. Survival data was reported as "dead" or "alive" to facilitate meta-analysis. Significant differences were detected only when comparing survival rates of thymoma patients in stages I to III with those of stage IV disease. Analysis by World Health Organization histologic type and stage yielded significant differences only in patients with thymomas A vs. B2 and A vs. B3 in stage III disease. No significant data heterogeneity was detected with funnel plots and Egger's regression test. Power analysis estimated that a study with 7077 patients is needed to evaluate the prognostic significance of all thymomas stratified by both World Health Organization histologic type and stage to a power of 80%. Selected World Health Organization histologic types are significantly associated with prognosis in stage III thymoma patients and may help select individuals benefiting from neoadjuvant therapy. Power analysis shows that studies with much larger number of patients are needed to exclude the possibility that histologic type may provide significant prognostic information in other stages of the disease.

Air-leak management after upper lobectomy in patients with fused fissure and chronic obstructive pulmonary disease: a pilot trial comparing sealant and standard treatment

A pilot trial to compare the efficacy of two different procedures to prevent postoperative air-leak in chronic obstructive pulmonary disease (COPD) patients submitted to upper lobectomy for non-small cell lung cancer. Sixty patients with COPD and lung cancer at the upper pulmonary lobes eligible for lobectomy were enrolled and randomly assigned either to standard treatment (ST) with stapling device or to electrocautery dissection and application of a collagen patch coated with human fibrinogen and thrombin (TachoSil) (experimental treatment [ET]) for the intra-operative completion of their fused fissures. Thirty patients were enrolled in each group during a three-year period. Preoperative characteristics were similar between the two groups. Statistically significant reduction of air-leak was registered in the ET group when overall incidence of postoperative air-leak (55% vs. 96%; P=0.03), postoperative air-leak (mean 1.63+/-1.96 vs. 4.33+/-4.12 days; P=0.0018), chest-drain (mean 3.53+/-1.59 vs. 5.90+/-3.72 days; P=0.0021) and hospital stay duration (mean 5.87+/-1.07 vs. 7.50+/-3.20 days; P=0.01) were considered. The use of TachoSil to prevent postoperative air-leak after interlobar fissure completion in patients with COPD submitted to upper lobectomy seems to be safe and more effective than the ST based on stapling device application.

Prevention of malignant seeding at drain sites after invasive procedures (surgery and/or thoracoscopy) by hypofractionated radiotherapy in patients with pleural mesothelioma

INTRODUCTION

Literature data show that mesothelioma cells can implant along the surgical pathway of invasive procedures such as thoracotomy and thoracoscopy. We investigated the use of hypofractionated radiotherapy for preventing such malignant seeding.

MATERIAL AND METHODS

Thirty-two consecutive patients diagnosed with pleural mesothelioma were included in the present retrospective study. All patients underwent surgery and/or thoracoscopy for diagnosis, staging or talc pleurodesis. They were treated with electron external beam radiation therapy (21 Gy in 3 fractions over 1 week), directed to the surgical pathway after the invasive procedure. After completion of radiation treatment, 20 of 32 patients (63%) underwent chemotherapy.

RESULTS

After a mean follow-up of 13.6 months (range 3-41) from the end of radiation therapy, no patient had tumour progression in the treated area. The treatment was well tolerated, as only erythema grade I (Radiation Therapy Oncology Group, RTOG, scale) was noted in 11 patients. Seventeen patients died of disease with local progression after a mean survival time of 12.6 months (range 3-27); thirteen patients are alive with disease after a mean follow-up of 13.9 months (range 4-41); two patients are alive without evidence of disease after a mean follow-up of 16.50 months (range 6-27).

DISCUSSION

The present study shows the efficacy and safety of local radiotherapy in preventing malignant seeding after thoracoscopy in patients with pleural mesothelioma although larger prospective trials are probably still needed to validate this treatment approach.

Lymph node isolated tumor cells and micrometastases in pathological stage I non-small cell lung cancer: prognostic significance

OBJECTIVE

To determine the prevalence and prognostic significance of lymph node micrometastases and isolated tumor cells (ITC) in patients submitted for radical resection for pathological stage I non-small cell lung cancer (NSCLC).

METHODS

From January 1998 through December 2005, 87 consecutive pT1-2, pN0 NSCLC patients were enrolled. Surgical specimens were submitted to pathological routine examinations to define histotype, grade, stage, vascular invasion, necrosis and tumor proliferative index. A total of 694 regional lymph nodes were examined by means of serial sections stained with hematoxylin and eosin and labelled by immunohistochemistry (antibody AE1/AE3, DAKO). Relationships between these parameters and patients' prognosis were investigated.

RESULTS

By histological examination, there were 36 squamous-cell carcinoma, 38 adenocarcinoma and 13 large-cell carcinoma. Micrometastases and ITC were detected in 19 lymph nodes (2.7%) of 14 patients (16%). Significant correlation was observed between micrometastases or ITC and adenocarcinoma (p=0.03) and the absence of necrosis (p=0.05). No relationship was demonstrated between micrometastases or ITC and T-status, vascular invasion or proliferative index (p>0.05). Median follow-up was 3.2 (range 0.25-8.6) years. Two- and 5-year disease-free survival was similar for patients with and without micrometastases or ITC (79% and 64% vs 81% and 64%, respectively). Recurrence occurred in three patients with (two local, 66%) and in 21 patients without micrometastases or ITC (three local, 14%) (p=0.186). By multivariate analysis only T-status was demonstrated to be a significant prognostic factor.

DISCUSSION

Micrometastases or ITC to regional lymph nodes are demonstrated to be not a rare aspect of pathological stage I resected lung cancer. In our series, the presence of lymph nodes micrometastases does not affect long-term disease-free survival.

Prognostic role of the extent of peritumoral vascular invasion in operable breast cancer

BACKGROUND

The clinical relevance of the degree of peritumoral vascular invasion (PVI) in patients with no or limited involvement of the axillary nodes is unknown.

MATERIALS AND METHODS

2606 consecutive patients with pT1-3, pN0 (1586)-1a (1020) and M0, operated and counseled for medical therapy from 1/2000 to 12/2002, were prospectively classified according to the degree of PVI: absent (2017, 77.4%), focal (368, 14.1%), moderate (51, 2.0%) and extensive (170, 6.5%).

RESULTS

Patients with extensive PVI were more likely to be younger, to have larger tumors, high tumor grade, axillary-positive nodes, high Ki-67 expression and HER2/neu over-expression compared with patients having less PVI (P for trend, <0.0001). In patients with node-negative disease a statistically significant difference in disease-free survival (DFS), risk of distant metastases and overall survival (OS) was observed at the multivariate analysis for extensive PVI versus no PVI (hazard ratios: 2.11, 95% CI, 1.02 to 4.34, P = 0.04 for DFS; 4.51, 95% CI, 1.96 to 10.4, P< 0.001 for distant metastases; 3.55, 95% CI, 1.24 to 10.1, P = 0.02 for OS).

CONCLUSIONS

The extent of vascular invasion should be considered in the therapeutic algorithm in order to properly select targeted adjuvant treatment.

Detection of oncogenic viruses (SV40, BKV, JCV, HCMV, HPV) and p53 codon 72 polymorphism in lung carcinoma

As a part of our continuous search for oncogenic viruses in bronchial cancer, we extended our HPV studies to analyse also SV40, BKV, JCV and HCMV sequences in bronchial cancer and related these data with p53 codon 72 polymorphism. Fresh tumor samples from 78 patients with lung cancer were analysed for SV40, BKV, JCV, HCMV and HPV sequences by PCR. HPV genotypes were determined using reverse blot hybridization and sequencing, and all HPV-positive tumors were tested for the presence of E6/E7 transcripts by RT-PCR. All samples were analysed for p53 codon 72 polymorphism, using PCR-based RFLP method. Of the 78 cases studied, 11 (14.1%) were positive for T-Ag gene of SV40, while BKV and JCV sequences were both amplified in 1 tumor only. Altogether, 10/78 lesions were HPV-positive; six HPV16, one HPV31, two HPV6/53 and one HPV16/18. All HPV DNA-positive samples except one also expressed E6 and E7 transcripts. HCMV was amplified in 18 (23%) cases. RFLP analysis of p53 codon 72 revealed 32 homozygotes for arg/arg allele (50.8%), 26 heterozygotes for arg/pro allele (41.3%), and 5 homozygotes for pro/pro allele (7.9%). P53 codon 72 polymorphism was not significantly different between cases (n=63) and controls (n=50) (p=0.455), among virus positive and negative patients, nor was it related to HPV genotypes (p=0.384), expression of E6 (p=0.384) and E7 oncogenes (p=0.293). Of all possible combinations of virus co-detection, only SV40-HCMV association was statistically significant (OR=5.500, 95%CI 1.43-21.02; p=0.015). Taken the known mechanisms of these individual viruses, there is a chance that these viruses could affect cell cycle control and inhibit apoptosis, thus potentially causing genetic instability and promote oncogenesis.

Prognostic role of the extent of peritumoral vascular invasion in operable breast cancer

10586

Background: Peritumoral vascular invasion (PVI) has been recently recognized as a significant prognostic indicator for women with operable breast cancer, yet the clinical relevance of the degree of PVI in patients with no or limited involvement of the axillary nodes is unknown. Methods: 2606 consecutive patients with pT1–3, pN0 (1586)-1a (1020), and M0, operated and counseled for medical therapy from 1/2000 to 12/2002 were prospectively classified according to the degree of PVI: absent (2017, 77.4%), focal (368, 14.1%), moderate (51, 2.0%) and extensive (170, 6.5%). The median follow-up was 3.8 years for disease-free survival (DFS) and 4.3 years for overall survival (OS). Results: Patients with extensive PVI were more likely be younger, to have larger tumors, high tumor grade, axillary positive nodes, high Ki-67 expression, and HER2/neu over-expression if compared with patients having less amount if PVI (p for trend, <.0001). Patients with diffuse PVI were prescribed significantly more frequently anthracycline containing chemotherapy and less endocrine therapy alone (p for trend, <.0001). In patients with node negative disease a statistically significant difference in DFS, risk of distant metastases and OS was observed at the multivariate analysis for diffuse PVI versus no PVI (Hazard Ratios: 2.11, 95% CI, 1.02 to 4.34, P<.0001 for DFS; 4.51, 95% CI, 1.96 to 10.4, P<.0001 for distant metastases; 3.55, 95% CI, 1.24 to 10.1, P=.02 for OS). Conclusions: Extensive peritumoral vascular invasion has a prognostic role in patients with axillary lymph node negative breast cancer. The extent of vascular invasion should be considered in the therapeutic algorithm in order to proper select targeted adjuvant treatment.

No significant financial relationships to disclose.

The role of surgery in the management of solitary pulmonary nodule in breast cancer patients

AIMS

To assess the role of surgery in the diagnosis and treatment of a solitary pulmonary nodule (SPN) in patients who had received previous surgery for breast cancer.

METHODS

A series of 79 consecutive patients who underwent surgery for an SPN between 1990 and 2003 after a curative resection for breast cancer were reviewed.

RESULTS

Surgical diagnosis was obtained by open procedure before 1996 (37 cases), and by video-assisted thoracoscopic surgery (VATS) after 1996 (33 out of 42 cases, 9 open procedures) and intraoperative evaluation. Histology of SPN was primary lung cancer in 38 patients, pulmonary metastasis of breast cancer in 27, and benign condition in 14. VATS was converted to open procedure for anatomical resection in primary lung cancer and for the palpation of the lung in metastatic disease. Average disease-free interval from the initial mastectomy was significantly longer in primary lung cancer than in metastatic patients (179+/-107 vs 51+/-27 moths). Manual palpation identified multiple pulmonary nodules in 3 out of 27 metastatic patients. Five-year survival rate after pulmonary metastasectomy was 38% and was significantly influenced by disease-free interval; 5-year survival rate after resection of primary lung cancer was 43% and was significantly influenced by the pathological stage.

CONCLUSIONS

VATS is a good procedure for diagnostic management of peripheral SPN. As SPN in breast cancer patients is primary lung cancer in half cases, it deserves confirmation of pathological diagnosis and appropriate surgical treatment. When breast cancer metastasis is demonstrated, open procedure must be performed to palpate the entire lung to exclude previously unknown nodules.

Simultaneous diagnosis of CD3+ T-cell large granular lymphocyte leukaemia and true thymic hyperplasia

CD3+ T-cell large granular lymphocyte (LGL) leukaemia is a mature T-cell neoplasm of cytotoxic T-lymphocytes. Neutropenia represents the most frequent peripheral blood cytopenia associated with CD3+ T-cell LGL leukaemia. A wide variety of diseases associated with LGL leukaemia have been reported, both autoimmune and neoplastic. We describe for the first time the association of true thymic hyperplasia with CD3+ T-cell line LGL leukaemia. The patient presented with severe symptomatic neutropenia. Complete and persistent haematological and molecular remission was induced with an association of low-dose methotrexate and cyclosporin A, followed by thymectomy.