Correlation of EGFR mutations with chromosomal alterations and expression of EGFR, ErbB3 and VEGF in tumor samples of lung adenocarcinoma patients

INTRODUCTION

Mutations in the tyrosine kinase domain of the epidermal growth factor receptor (EGFR) are frequently detected in lung adenocarcinomas with bronchioloalveolar (BAC) differentiation and have been associated with increased response to small molecule EGFR inhibitors in some clinical studies. However, further molecular characterization of tumor cells carrying EGFR mutations (EGFR-mut) is warranted.

METHODS

By DNA sequencing, 120 patients with lung adenocarcinomas (70 tumors with BAC components) were screened for EGFR mutations within exons 18-21. Performing comparative genomic hybridization (CGH) and immunohistochemistry, chromosomal imbalances and protein expression levels of EGFR, ErbB3 and VEGF (vascular endothelial growth factor) were analyzed, respectively.

RESULTS

EGFR mutations were detected in 20/120 tumors. Tumors with BAC components carried more frequently EGFR mutations compared to adenocarcinomas without BAC histology (17/70=24% vs 3/50=6.0%; p=0.012). In a subsequent matched-pair analysis, CGH-analysis demonstrated similar mean numbers of chromosomal imbalances for EGFR mutated and wild-type tumors (8.6 vs 7.8 gains; 2.4 vs 2.7 losses), respectively. Furthermore, tumors with mutated EGFR demonstrated gains in chromosomes 7p, 16p and 20q and losses in chromosome 8p. Interestingly, EGFR mutated tumors showed higher VEGF expression (p=0.03) while differences in EGFR expression were not statistically significant.

CONCLUSION

EGFR gene mutations are frequently seen in lung adenocarcinomas with BAC differentiation and can be linked to chromosomal imbalances and increased VEGF expression.

Early onset lung cancer, cigarette smoking and the SNP309 of the murine double minute-2 (MDM2) gene

The polymorphism SNP309 (rs2279744) in the promoter region of the MDM2 gene has been shown to alter protein expression and may play a role in the susceptibility to lung cancer. The MDM2 protein is a key inhibitor of p53 and several mechanisms of MDM2/p53 interactions are presently known: modulating DNA-repair, cell-cycle control, cell growth and apoptosis.

We used 635 Caucasian patients diagnosed with lung cancer before 51 years of age and 1300 healthy gender and age frequency matched population Caucasian controls to investigate the association between the MDM2 SNP309 and the risk of developing early onset lung cancer. Conditional logistic models were applied to assess the genotype-phenotype association, adjusted for smoking.

Compared to the GG genotype, the adjusted ORs for the TG and TT genotype were 0.9 (95% CI: 0.7–1.5) and 1.0 (95% CI: 0.7–1.5), respectively. Also no association was found for histological subtypes of lung cancer. The strength of this study is that within young cases the genetic component to develop lung cancer may be greater. Our results indicate that the MDM2 SNP309 is not significantly associated with lung carcinogenesis but point towards gender-specific differences.

A retrospective analysis of short and long-term survival after curative pulmonary resection for lung cancer in elderly patients

In this retrospective study we analyzed the age-related mortality and the long-term survival of a total of 2021 subjects (male: n=1509; female: n=512) who underwent major pulmonary resections (lobectomy, pneumonectomy) in curative intention for primary non-small cell lung cancer (NSCLC). As controls, patients were divided into three groups of age: subjects >75 years of age (n=119), subjects 65-75 years of age (n=587) and subjects <65 years of age (n=1315). Overall mortality after lobectomy was 1.4% (21/1505 patients); age-related mortality was 0.9% (n=8/919) in subjects aged <65 years, 1.9% (n=9/486) in subjects aged 65-75 years, and 4.0% (n=4/100) in subjects aged >75 years. Overall mortality after pneumonectomy was 4.3% (22/516 patients); age-related mortality was 3.0% (n=12/396) in subjects aged <65 years, 7.9% (n=8/101) in subjects aged 65-75 years, 10.5% (n=2/19) in subjects aged >75 years. The overall 5-year survival rates were 52.5% (age: <65 years), 45.8% (age: 65-75 years), and 50% (age: >75 years). There was no significant difference in overall survival between age groups. However, an impaired performance status (ECOG status grades 1-3) had a significant negative impact on survival in subjects >65 years (p=0.017), and in subjects >75 years (p=0.002). We conclude, medically fit elderly patients should not be denied surgery of resectable non-small cell lung cancer based on their chronologic age alone. Curative pulmonary resections due to lung cancer can be performed safely in those elderly patients that are fulfilling the common criteria of operability.

[Treatment of pleural empyema]

Pleural empyema remains a frequently encountered clinical problem and is responsible for significant morbidity and mortality worldwide. Its diagnosis may be difficult; delays in diagnosis and treatment may contribute to morbidity, complications, and mortality. The management of parapneumonic effusion and empyema depends on timely, stage-dependent therapy and the underlying etiology. Thoracentesis and antibiotics remain the cornerstones of treatment in stage I disease. In the early fibrinopurulent phase (stage II) thoracoscopic methods should be considered. As treatment strategy for this stage, fibrinopurulent pleural empyema entails thorough debridement of multiloculated collections from the pleural cavity by video-assisted thoracic surgery. After evacuation of multilocular effusions and the removal of fibrin deposits with drainage by two intercostal chest tubes, irrigation treatment helps to achieve clarity of the pleural discharge. Open thoracotomy and decortication are reserved for organized, multiloculated empyema with lung entrapment (stage III disease). Early drain removal may lead to rapid symptomatic recovery and complete resolution.

[Treatment of pneumothorax]

Pneumothorax is defined as air in the pleural space, i.e. between the lung and the chest wall. Primary pneumothoraces (PSP) arise in otherwise healthy people without any lung disease. Secondary pneumothoraces (SSP) arise in subjects with underlying lung disease. Observation alone is recommended only in patients with small primary or secondary pneumothoraces of less than 1 cm depth or isolated apical pneumothoraces in asymptomatic patients. In symptomatic patients observation alone is inappropriate and active intervention is required. Although simple aspiration may be an option for first-line treatment in clinically stable patients with PSP, intercostal tube drainage is strongly recommended in all primary and secondary pneumothoraces requiring intervention. There are two objectives in the surgical management of pneumothorax. The first widely accepted objective is resection of blebs or the suture of apical perforations to treat the underlying defect. The second objective is to create a pleural symphysis to prevent recurrence. While video-assisted thoracic surgery may be the preferred surgical procedure for young, fit people with complicated or recurrent primary pneumothoraces, it is less reliable in cases of secondary pneumothorax. For the latter, open thoracotomy and repair is still the recommended approach.

Surgical resection of pulmonary metastases from colorectal cancer: a systematic review of published series

The treatment of patients with pulmonary metastases from colorectal cancer continues to evolve. Recently the use of novel agents as a first-line treatment in metastatic colorectal disease has generated cautious optimism in the oncological community. However, pulmonary metastasectomy remains a mainstay in a multidisciplinary concept for a highly selected subset of patients. A selected group of patients with metastases limited to the lungs may benefit from pulmonary metastasectomy with a 5-year survival rate of up to more than 50%. This review evaluates the current status of surgical resection in pulmonary metastases from colorectal cancer, with special emphasis on prognostic factors that influence survival, as well as on surgical approach and lymph node dissection and its impact on the management of patients with metastatic colorectal disease.

Bilateral surgical resection in pulmonary epitheloid hemangioendothelioma

Epitheloid hemangioendothelioma is a vascular tumour with an epitheloid appearance, originating from endothelial cells. Although it is a slow growing tumour, extensive pulmonary involvement, intrathoracic spread, and systemic spread have been documented. We present a case of epitheloid hemangioendothelioma of the lung in a patient with an initial diagnosis made by transthoracic biopsy. The prognosis is unpredictable, with life expectancy ranging from 1 to 20 years. There is no single effective treatment, though spontaneous regression and response to chemotherapy and interferon are reported. Our patient underwent pulmonary lobectomy of the right lower lobe and pulmonary wedge resection of the nodule located in the left lower lobe.

Management of Iatrogenic Tracheobronchial Injuries: A Retrospective Analysis of 29 Cases

BACKGROUND

Tracheobronchial injuries are rare but potentially life-threatening complications of endotracheal intubations or endobronchial interventions. This retrospective analysis discusses the criteria for the operative and nonoperative management of tracheal lacerations.

METHODS

From July 1996 to June 2006, 29 patients with iatrogenic tracheobronchial injuries were diagnosed at our institution. The injury occurred during single-lumen tube intubation in 14 patients and during double-lumen tube intubation in 2 patients. Two ruptures were diagnosed after surgical tracheostomy, eight after dilational percutaneous tracheostomy, and three after interventional bronchoscopy.

RESULTS

The lacerations in 11 patients were superficial or were sufficiently covered by the esophagus, and they underwent conservative management. Bronchoscopy revealed healing per primam in every case. Surgical repair was done in 18 patients (62%). The transtracheal approach was used for repair in 7 patients; a right-sided posterolateral thoracotomy was performed in 11 patients with lacerations affecting the lower third of the trachea. Three surgical patients died from causes unrelated to the tracheal injury. No clinically evident mediastinitis or postoperative tracheobronchial stenosis was observed.

CONCLUSIONS

The decision for operative or nonoperative treatment of iatrogenic tracheobronchial lacerations is determined by the ventilating situation and the local extent of the injury. Nonoperative management of iatrogenic tracheobronchial injuries may be a save option in patients with uncomplicated ventilation, superficial or sufficiently covered tears, and moderate and nonprogressive emphysema. Immediate surgical repair remains warranted in those patients who require mechanical ventilation that cannot be delivered past the laceration.

Mutational status of the epidermal growth factor receptor (EGFR) gene in thymomas and thymic carcinomas

Epithelial tumours of the thymus (thymoma, thymic carcinoma) are rare tumours of the anterior mediastinum. Current treatment options of advanced stage thymomas and thymic carcinomas include a multimodal therapy with radio- and chemotherapy as well as surgery. In recent years, new therapeutic targets such as EGFR (epidermal growth factor receptor), COX-2 and KIT have emerged as new potential therapeutic targets. So far, EGFR mutational status of different subtypes of epithelial tumours of the thymus has been analyzed only inappropriately. We have investigated 20 different subtypes of thymomas (type A, AB, and B3) and thymic carcinomas for mutations in exons 18, 19, 20, and 21 of the EGFR gene and performed immunohistochemistry for EGFR. Concerning immunohistochemistry, most of the cases (17/20) had a strong positive staining. Although sequence alterations were found in four samples, none of these alterations led to amino acid changes in the tyrosine kinase domain of EGFR comparable to those in non-small cell lung cancer. Thus EGFR-expression in thymic tumours does not rely on mutations in critical functional (activation) domains of the EGFR-gene. Experimental and therapeutic approaches have to consider this difference.

Clinical and mechanistic aspects of glucocorticoid-induced chemotherapy resistance in the majority of solid tumors

BACKGROUND

Glucocorticoids have been used widely in conjunction with cancer therapy due to their ability to induce apoptosis in hematological cells and to prevent nausea and emesis. However, recent data including ours, suggest induction of therapy-resistance by glucocorticoids in solid tumors, although it is unclear whether this happens only in few carcinomas or is a more common cell type specific phenomenon.

MATERIAL AND METHODS

We performed an overall statistical analysis of our new and recent data with 157 tumor probes evaluated in vitro, ex vivo and in vivo. The effect of glucocorticoids on apoptosis, viability and cell cycle progression under diverse clinically important questions was examined.

RESULTS

New in vivo results demonstrate glucocorticoid-induced chemotherapy resistance in xenografted prostate cancer. In an overall statistical analysis we found glucocorticoid-induced resistance in 89% of 157 analysed tumor samples. Resistance is common for several cytotoxic treatments and for several glucocorticoid-derivatives and due to an inhibition of apoptosis, promotion of viability and cell cycle progression. Resistance occurred at clinically achievable peak plasma levels of patients under anti-emetic glucocorticoid therapy and below, lasted for a long time, after one single dose, but was reversible upon removal of glucocorticoids. Two nonsteroidal alternative anti-emetic agents did not counteract anticancer treatment and may be sufficient to replace glucocorticoids in cotreatment of carcinoma patients.

CONCLUSION

These data demonstrate the need for prospective clinical studies as well as for detailed mechanistic studies of GC-induced cell-type specific pro- and anti-apoptotic signalling.

[Prognosis after complete surgical resection for non-small cell lung cancer based on the staging classification]

BACKGROUND AND OBJECTIVE

The importance of accurate staging according to the international TNM staging system of non-small cell lung cancer (NSCLC) for patient management and ascertaining individual prognosis cannot be overemphasized. The TNM classification is scheduled to be revised in 2007. In a large single-center collective we investigated the prognosis for patients who had complete resection of a NSCLC.

PATIENTS AND METHODS

We retrospectively reviewed hospital records and follow-up data of 2,378 patients operated on between 1996 and 2005 for NSCLC. Complete resection was achieved in 2,083 patients. Systematic hilar and mediastinal lymph node dissection was performed concurrently. Probability of survival was then analysed with the Kaplan-Meier method. The significance of differences between subgroups was calculated using the log-rank test. Odds ratios with 95 % confidence intervals (CI) were calculated for each characteristic. The Cox model was used for multivariate analyses.

RESULTS

The 5-year survival for patients after complete resection was 50.7 %. The 5-year survival rates for clinical stages were 72 % for stage IA, 59.8 % for stage IB, not defined for stage IIA, 47,8 % for stage IIB, 45 % for stage IIIA, 38.7 % for stage IIIB, and not defined for stage IV. There were significant differences in survival between stages IIIB and IV (p = 0.013). There was a trend towards significance between patients with IA and IB (p = 0.052). However, there was no significant difference between patients with all the other stages. 5-year survival according to pathological stages was: stage IA 68.5 %; stage IB 66.6 %; stage IIA 55.3 %; stage IIB 49.0 %; stage IIIA 35.8 %; stage IIIB 35.4 %; stage IV not defined. Gender, age and type of histology were found by multivariate analysis to be significant independent prognostic factors for survival.

CONCLUSIONS

The TNM and stage grouping classification is valid for defining prognosis and prognosis-related criteria in patients with NSCLC. The difference in prognosis between clinical stages IIIB and IV was significant, but not that between all the other related subgroups. Concordance with histological staging demonstrated the quality of existing clinical staging methods and related strategies. Complete surgical resection, age, gender, histology and stage of the disease significantly influenced long-term survival.

Endobronchial ultrasound-guided transbronchial needle aspiration of lymph nodes in the radiologically normal mediastinum

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) can sample enlarged mediastinal lymph nodes in patients with nonsmall cell lung cancer (NSCLC). To date, EBUS-TBNA has only been used to sample nodes visible on computed tomography (CT). The aim of the present study was to determine the accuracy of EBUS-TBNA in sampling nodes <or=1 cm in diameter. NSCLC patients with CT scans showing no enlarged lymph nodes (no node >1 cm) in the mediastinum underwent EBUS-TBNA. Identifiable lymph nodes at locations 2r, 2l, 4r, 4l, 7, 10r, 10l, 11r and 11l were aspirated. All patients underwent subsequent surgical staging. Diagnoses based on aspiration results were compared with those based on surgical results. In 100 patients (mean age 58.9 yrs; 68 males), 119 lymph nodes ranging 5-10 mm in size were detected and sampled. Malignancy was detected in 19 patients but missed in two; all diagnoses were confirmed by surgical findings. The mean diameter of the punctured lymph nodes was 8.1 mm. The sensitivity of EBUS-TBNA for detecting malignancy was 92.3%, specificity was 100%, and the negative predictive value was 96.3%. No complications occurred. In conclusion, endobronchial ultrasound-guided transbronchial needle aspiration can accurately sample even small mediastinal nodes, therefore avoiding unnecessary surgical exploration in one out of six patients who have no computed tomography evidence of mediastinal disease. Potentially operable patients with no signs of mediastinal involvement on computed tomography may benefit from pre-surgical endobronchial ultrasound-guided transbronchial needle aspiration and staging.

Elevated risk of squamous-cell carcinoma of the lung in heavy smokers carrying the variant alleles of the TP53 Arg72Pro and p21 Ser31Arg polymorphisms

Alterations in cell cycle regulation and apoptosis leading to malignant transformation could be caused by common genetic variants in tumor suppressor genes. The effects of the TP53 polymorphism Arg72Pro on lung cancer risk have been investigated in numerous studies with, however, conflicting results. In many studies, important risk modifiers such as smoking or tumor histology were not taken into account. We therefore investigated the combined effects of polymorphisms in TP53 (Arg72Pro) and p21/CDKN1A (Ser31Arg) and smoking on lung cancer risk. Our case-control study consisted of 405 patients with lung cancer, mainly squamous-cell carcinoma (185) and adenocarcinoma (177) and 404 unmatched tumor-free hospital controls. Multivariate regression analysis showed a moderate but statistically significant risk of lung cancer overall and especially of squamous-cell carcinoma (OR, 1.65; CI, 1.10-2.47) for TP53 72Pro allele carriers. The risk was markedly increased in heavy smokers (>20 pack-years) with squamous-cell carcinoma (OR, 2.80 in patients homozygous for 72Pro; CI, 1.19-6.58), but not in light smokers (<or=20 pack-years). The results for the p21 Ser31Arg polymorphism suggested that 31Ser is a moderate-risk allele for squamous-cell carcinoma. Analysis of the combined effects of the two polymorphisms revealed a higher OR for TP53 72Pro carriers homozygous for p21 31Ser than for 72Pro carriers in general; this effect being most pronounced in heavy smokers with squamous-cell carcinoma (OR, 3.84; CI, 1.46-10.1). Our data indicate that the TP53 Arg72Pro polymorphism increases the risk for squamous-cell carcinoma mainly in heavy smokers. The observed interaction with smoking is biologically plausible as, for the 72Pro p53 variant, decreased apoptosis and extended G1 cell cycle arrest is reported after carcinogen exposure. Nevertheless, confirmation by further molecular and epidemiological studies is warranted.

Surgical treatment of primary soft tissue sarcomas involving the chest: experiences in 25 patients

BACKGROUND

Primary soft tissue sarcomas of the chest wall are uncommon and data concerning treatment and results are sparse. We reviewed our experience with chest wall resections of these lesions.

METHODS

Retrospective review of our database identified 25 patients (12 men, 13 women) who underwent chest wall resection for primary soft tissue sarcoma during the 18-year study period (January 1984 through to January 2002). The mean follow-up period was 46.5 months.

RESULTS

The 30-day mortality was zero. The cumulative 5-year survival rate of all 25 patients was 56.9 %, and the median survival 99.5 months. This compared with 42.2 % and a median survival of 36.0 months after chest wall resection for high grade tumor histology. Histological type grading clearly influenced long-term survival ( P = 0.036). Local recurrence occurred in 9 patients, 6 of 8 who were resected with positive margins and 3 of 17 who were resected with negative margins. Chest wall resections extended with lung resections did not significantly impair postoperative pulmonary function compared to patients without concomitant lung resections.

CONCLUSIONS

Chest wall resections in primary soft tissue sarcomas can be accomplished safely with a low mortality rate. Long-term survival can be achieved for primary soft tissue sarcomas but histological grading is of prognostic significance.

Pulmonary Metastasectomy Following Chemotherapy in Patients with Testicular Tumors: Experience in 52 Patients

BACKGROUND

Surgical resection is an important form of treatment for residual post-chemotherapy pulmonary masses in patients with non-seminomatous germ cell tumors. We analyzed the outcome and prognostic factors after surgery.

METHODS

Between 1996 and 2001, 52 patients underwent pulmonary resection of thoracic masses following cisplatin-based chemotherapy. These patients' records were subsequently reviewed.

RESULTS

The overall 5-year survival rate was 75.8 %. A significantly longer survival was observed using multivariate analysis in patients with normal serum AFP and/or hCG tumor marker levels and after complete surgical resection. In patients with viable malignant tumor cells in the resected specimen and in patients with only necrosis/fibrosis or teratoma, the 5-year survival rates were 49.6 % and 82.8 %, respectively. This difference was only statistically significant in univariate analysis.

CONCLUSIONS

We conclude that pulmonary resection in metastatic non-seminomatous germ cell tumors is a safe and effective treatment modality. Incomplete resection and elevated tumor marker levels, AFP and/or hCG, were identified as prognosis-related criteria for a poor outcome in multivariate analysis.

Pulmonary Metastasectomy in Patients with Soft Tissue Sarcomas: Experiences in 50 Patients

BACKGROUND

Pulmonary resection of metastatic soft tissue sarcomas is an accepted method of treatment. The purpose of this study was to determine the clinical course, outcome and prognostic factors after surgery.

METHODS

Between 1996 and 2001, 50 patients (27 men, 23 women) with pulmonary metastases from a soft tissue sarcoma underwent surgical resection. Inclusion criteria for the study were the absence of primary tumor recurrence and other extrapulmonary metastases. Complete resection (CR) was achieved in 31 patients.

RESULTS

The overall 5-year survival rate was 37.6 %. The 5-year survival rate after complete metastasectomy was 52.7 %, but none of the patients who underwent incomplete resection survived 3 years. Complete resection was found to be a significant prognostic factor for survival following metastasectomy ( P < 0.0001). Of the prognostic factors analyzed, age, sex, repeat thoracotomy, thoracic lymph node involvement, number of metastases, disease-free interval, histology and histological grading did not influence survival.

CONCLUSION

We conclude that pulmonary resection of metastatic soft tissue sarcomas is a safe and effective treatment, which offers an improved survival benefit. Prognosis-related criteria are identified which support the necessity of complete surgical resection of all clinically detected metastases.