KRAS mutations in non-small-cell lung cancer and colorectal cancer: implications for EGFR-targeted therapies.

BACKGROUND: KRAS mutations are associated with diverse biologic functions as well as prognostic and predictive impact in non-small cell-lung cancer (NSCLC) and colorectal cancer (CRC). In CRC, benefit from monoclonal antibody therapies targeting EGFR is generally limited to patients whose tumors have wild-type (WT) KRAS, whereas data suggest that this association is not present for NSCLC. We hypothesized that the unique tobacco-related carcinogenesis of NSCLC results in a divergence of KRAS MT genotype compared with CRC, contributing to differences in outcomes from EGFR-targeted therapies. MATERIAL AND METHODS: Tumor from 2603 patients (838 CRC and 1765 NSCLC) was analyzed for KRAS mutations. DNA was extracted from microdissected formalin-fixed-paraffin-embedded specimens (FFPE) and 7 different base substitutions in codons 12 and 13 of KRAS were determined. RESULTS: KRAS mutation genotype differed significantly between NSCLC and CRC in frequency (25% vs. 39%; p<0.001), smoking-associated G>T transversions (73% versus 27%; p<0.001), and ratio of transversions to transitions (3.5 vs. 0.79; p<0.001). In NSCLC GLY12Cys mutations, resulting from a codon 12 GGT>TGT substitution, were observed in 44% compared to 10% for CRC. In contrast, codon 12 or 13 GLY>ASP substitutions (resulting in a G>A transition) were more frequent in CRC (42%) compared with NSCLC (21%). CONCLUSION: In this large dataset, KRAS mutation patterns are quantitatively and qualitatively distinct between NSCLC and CRC, reflecting in part differences in tobacco-related carcinogenesis. In light of differences in predictive value for EGFR-directed monoclonal antibody therapy and prognosis for specific KRAS mutations between NSCLC and CRC, these data provide an underlying biologic rationale.

MicroRNA profiling in locally advanced esophageal cancer indicates a high potential of miR-192 in prediction of multimodality therapy response.

To identify possible predictive markers, our study aimed to characterize microRNA (miRNA) profiles of responder and nonresponder in the multimodality therapy of locally advanced esophageal cancer. Initially, a microarray-based approach was performed including eight patients with esophageal cancer. Patients received neoadjuvant chemoradiation followed by surgical resection. Major histopathological response was defined if resected specimens contained less than 10% vital tumor cells (major/minor response: 4/4 patients). Intratumoral RNA was isolated from both, pretherapeutic tissue biopsies in addition to corresponding surgical specimens. The profile of 768 miRNAs was analyzed in 16 specimens (preneoadjuvant and postneoadjuvant therapy). Selected miRNAs were than analyzed on pretherapeutic and post-therapeutic biopsies of 80 patients with esophageal cancer, who underwent multimodality therapy (major/minor response: 30/50 patients). Comprehensive miRNA profiling identified miRNAs in pretherapeutic biopsies that were significantly different between major/minor responders. Based on the microarray results, miR-192, miR-194 and miR-622 were selected and the dysregulated miRNAs were studied on an extended series of esophageal cancer patients. The expression of miR-192, miR-194 and miR-622 was significantly reduced after neoadjuvant therapy confirming the array profiling data. Importantly, the pretherapeutic intratumoral expression of miR-192 and miR-194 was significantly associated with the histopathologic response of esophageal squamous cell carcinoma to multimodal therapeutic treatment. Therefore, in patients with locally advanced esophageal cancer undergoing neoadjuvant chemoradiation followed by esophagectomy, miR-192 and miR-194 in pretherapeutic biopsies are considered as indicators of major histopathologic regression.

The prognostic impact of extracapsular lymph node involvement in rectal cancer patients: Implications for staging and adjuvant treatment strategies.

Limited data suggest that extracapsular lymph node involvement (LNI) has a negative prognostic impact in gastrointestinal malignancies. The aim of this study was to assess the prevalence and prognostic impact of LNI in patients with primary resected rectal cancer. Between 1997 and 2007, 243 rectal cancer patients underwent surgical therapy without neoadjuvant treatment at our Department. Of these, 12 (5%) patients received transanal endoscopic microsurgery and were not included for further analyses. In the remaining patients, a (low) anterior resection was performed in 79% and an abdominoperineal rectal amputation in 21%. The total number of analyzed lymph nodes and the number of metastatic lymph nodes with/without extracapsular LNI were determined and the prognostic impact of LNI was assessed. The median number of analyzed lymph nodes was 14. In total, 59% of patients were node-negative, 18% of patients were node-positive without extracapsular LNI and 23% of patients were node-positive with extracapsular LNI. A positive lymph node status with extracapsular LNI was significantly correlated with a poorer T-, N- and M-category, grading and more frequent lymphatic vessel infiltration compared with node-negative or node-positive without extracapsular LNI patients (p<0.001). The overall 5-year survival rate of node-negative patients was 75%, for node-positive without extracapsular LNI patients 69% and for node-positive with extracapsular LNI patients 36% (p<0.001). By multivariate analysis, the N-category with extracapsular LNI was characterized as an independent prognostic factor. Extracapsular lymph node involvement reveals an independent negative prognostic impact in patients with rectal cancer undergoing surgical therapy. Staging systems for rectal cancer should include the implementation of extracapsular lymph node involvement.

Evaluation of histological regression grading systems in the neoadjuvant therapy of rectal cancer: do they have prognostic impact?

PURPOSE: Neoadjuvant treatment options have been developed to improve survival of patients with locally advanced rectal cancer. As only patients with a major histopatholocial response benefit from this preoperative therapy, several tumor regression grading systems have been developed. However, currently no accepted comprehensive grading system for clinical use is available. Therefore, we studied the impact of four histological regression grading systems in the neoadjuvant therapy of rectal cancer. METHODS: In this retrospective study, 85 patients with locally advanced rectal cancer were included. All patients received a neoadjuvant radiochemotherapy followed by surgical resection. The histological regression grading was evaluated using four classification systems: (1) grading system by the Japanese society of colorectal cancer, (2) grading system by Junker-Müller, (3) grading system by Dworak, (4) Cologne grading system. The four classification systems were analyzed for their prognostic impact. RESULTS: The following significant correlations were detected between the four classification systems and the ypTNM categories: (1) patients with a ypT3/4 category had significantly more often a worse histopathologic response in all four grading systems (p = 0.001); (2) a ypN0 category was significantly correlated with good histopathologic response only in the Cologne grading system; (3) in the Junker-Müller and Dworak grading systems, a ypM0 category was significantly correlated with a good histopathologic response (p = 0.046; p = 0.03). However, none of the used classification systems had a prognostic impact on survival. CONCLUSIONS: Currently, none of the analyzed histological regression grading systems is effective for clinical use.

TS and ERCC-1 mRNA expressions and clinical outcome in patients with metastatic colon cancer in CONFIRM-1 and -2 clinical trials.

To validate established cutoff levels of thymidylate synthase (TS) and excision repair cross-complementing (ERCC-1) intratumoral mRNA expressions in tumor samples from metastatic colorectal cancer (mCRC) patients treated with PTK787/ZK222584 (PTK/ZK). From 122 samples of patients with mCRC enrolled in CONFIRM-1 (Colorectal Oral Novel Therapy for the Inhibition of Angiogenesis and Retarding of Metastases) or CONFIRM-2, mRNA was isolated of microdissected formalin-fixed paraffin-embedded samples and quantitated using TaqMan-based technology. Existing TS and ERCC-1 cutoff levels were tested for their prognostic value in first-line and second-line therapy. TS expression was associated with overall survival (OS) in first-line, but not second-line therapy. ERCC-1 was associated with OS in patients treated with first-line and second-line FOLFOX4. In first-line FOLFOX4, combination of high TS and/or high ERCC-1 was associated with shorter OS. A correlation was observed between ERCC-1 expression and benefit from PTK/ZK+FOLFOX4 treatment. TS and ERCC-1 expression is associated with clinical outcome in mCRC. Baseline TS and ERCC-1 levels may allow the selection of patients who benefit from FOLFOX4 chemotherapy.

[Oesophageal cancer: current status of multimodality therapy]. / Ösophaguskarzinom: Aktueller Stand der multimodalen Therapie.

Multimodality treatment options have been widely promoted in the therapy for locally advanced oesophageal cancer (cT3/4Nx). Generally neoadjuvant chemotherapy and combined radiochemotherapy are frequently used in this setting. The recent meta-analyses evaluating randomised trials of different neoadjuvant therapy protocols prior to surgery for patients with locally advanced oesophageal cancer showed only a modest improvement in survivial of 5-10% survival at 5 years. In contrast, the meta-analyses reveal that patients with excellent histopathological responses seem to highly benefit from neoadjuvant regimens. Patients with poor histopathological responses have no benefit but rather disadvantegeous prognoses. Therefore, predictive markers to allow individualisation of multimodality treatment in locally advanced esophageal cancer are urgently needed.

[18F]-fluorodeoxyglucose-positron emission tomography for the assessment of histopathologic response and prognosis after completion of neoadjuvant chemotherapy in gastric cancer.

BACKGROUND AND OBJECTIVES: Neoadjuvant chemotherapy is applied to improve the prognosis of patients with advanced gastric cancer. However, only a major histopathological response will provide a benefit. Recent studies suggest that [(18)F]-fluorodeoxyglucose-positron-emission-tomography (FDG-PET) correlates with response and survival in patients with gastroesophageal adenocarcinomas undergoing neoadjuvant chemotherapy. We evaluated the potential of FDG-PET for the assessment of response and prognosis in the multimodality treatment of gastric cancer. METHODS: Study patients were recruited from a prospective observation trial. Forty two patients with advanced gastric cancer received neoadjuvant chemotherapy and subsequently 40 patients underwent standardized gastrectomy (2 patients with tumor progression had therapy limited to palliative chemotherapy without surgery). Histomorphologic regression was defined as major response when resected specimens contained <10% vital tumor cells. FDG-PET was performed before and 2 weeks after the end of neoadjuvant chemotherapy with assessment of the intratumoral FDG-uptake [pre-treatment standardized uptake value (SUV1); post-treatment SUV (SUV2); percentage change (SUVDelta%)]. RESULTS: Histomorphological tumor regression was confirmed as a prognostic factor (P = 0.039). No significant correlations between SUV1, SUV2, or SUVDelta% and response or prognosis were found. CONCLUSION: FDG-PET seems not to be an imaging system that effectively characterizes major/minor response and survival in patients with gastric cancer following multimodality treatment.

Lack of prognostic significance of serum DNA methylation of DAPK, MGMT, and GSTPI in patients with non-small cell lung cancer.

BACKGROUND AND OBJECTIVES: To further improve the screening, diagnosis and therapy of patients with non-small cell lung cancer (NSCLC) additional diagnostic tools are desperately warranted. Aim of this study was to investigate the potential of the DNA methylation of DAPK, MGMT, and GSTPI in serum of patients with NSCLC as a prognostic molecular marker in this disease. METHODS: Seventy-six patients with NSCLC were included in this study. The analysis of DNA methylation in serum of patients was performed on pre-operative samples. Following DNA isolation and bisulfite-treatment, DNA methylation was analyzed by quantitative-methylation-specific real-time PCR with beta-actin as the internal reference gene. RESULTS: DNA methylation was detectable with following frequencies: DAPK 68.4%, MGMT 7.9%, GSTPI 0%. There were no associations between DNA methylation status and histology, tumor stage, grading or gender detectable. With a mean follow-up of 19.7 months the median survival was 26.3 months. There were no associations between the status of DNA methylation in patient's serum and prognosis detectable. CONCLUSION: The analysis of DNA methylation in serum of patients with NSCLC by quantitative-methylation-specific real-time PCR is technically feasible. Although our results suggest quantification of DNA methylation in serum not of prognostic significance in this disease, further studies are warranted to determine the future potential of this molecular approach.

Survivin expression in gastric cancer: Association with histomorphological response to neoadjuvant therapy and prognosis.

BACKGROUND AND OBJECTIVES: Neoadjuvant therapy is applied to improve the prognosis associated with advanced gastric cancer. Only patients with a major response seem to have a survival benefit. Predictive markers to allow individualisation of treatment could be helpful. We examined the association of survivin protein expression with histopathologic response to neoadjuvant chemotherapy and prognosis in patients with gastric cancer. METHODS: Forty patients with gastric cancer received neoadjuvant chemotherapy. Afterwards, 38 patients underwent total gastrectomy, while 2 patients received definitive chemotherapy because of tumour progression. Histomorphologic regression was defined as major response when resected specimens contained <10% tumour cells. Intratumoural survivin expression was determined by immunohistochemistry in pre- and post-therapeutic specimens and correlated with clinicopathologic parameters. RESULTS: The pre- and post-therapeutic intratumoural survivin protein expression was not associated with histomorphologic regression. Post-therapeutic survivin expression did not have prognostic impact. A significant association was detected between pre-therapeutic survivin levels and prognosis: patients with a higher survivin protein expression showed a significant survival benefit. In multivariate analysis pre-therapeutic survivin expression was characterised as an independent prognostic marker, besides pN-status and histopathologic regression. CONCLUSIONS: The pre-therapeutic survivin protein expression seems to be an independent prognostic marker in the multimodality treatment of advanced gastric cancer.

HIF-1alpha protein expression is associated with the environmental inflammatory reaction in Barrett's metaplasia.

The oxygen-regulated transcription factor subunit hypoxia inducible factor-1alpha (HIF-1alpha) is involved in angiogenesis, energy metabolism, cell survival, and inflammation. We examined the protein expression of HIF-1alpha within the progression of Barrett's sequence as well as the type and degree of the environmental inflammatory reaction. Squamous epithelium (SE), metaplastic, low- and high-grade dysplastic lesions, and tumor tissue of 57 resection specimens from patients with Barrett's adenocarcinoma were immunohistochemically analyzed. Active and chronic inflammatory reactions were classified according to the Updated Sydney System. HIF-1alpha protein expression increased significantly from SE to Barrett's metaplasia (BM) (P < 0.0001). From metaplasia through low- and high-grade dysplasia to cancer, no further increase could be detected. Active and chronic inflammation were also significantly different between SE and BM (P < 0.0001) but not during further progression in the sequence. HIF-1alpha protein expression did not correlate with histopathologic parameters or survival. HIF-1alpha protein expression pattern resembles the active and chronic environmental inflammatory reaction. All were significantly increased in metaplasia compared to SE without further change in tumor development. HIF-1alpha protein expression appears to be associated with inflammatory processes in the development of BM.

GNAS1 T393C polymorphism is associated with histopathological response to neoadjuvant radiochemotherapy in esophageal cancer.

Recent studies have shown an association between the GNAS1 T393C polymorphism and clinical outcome for various solid tumors. In this study, we genotyped 51 patients from an observational trial on cisplatin/5-FU-based neoadjuvant radiochemotherapy of locally advanced esophageal cancer (cT2-4, Nx, M0) and genotyping was correlated with histomorphological tumor regression. The C-allele frequency in esophageal cancer patients was 0.49. Pearson's chi(2)-test showed a significant (P<0.05) association between tumor regression grades and T393C genotypes. Overall, 63% of the patients in the T-allele group (TT+CT) were minor responders with more than 10% residual vital tumor cells in resection specimens, whereas T(-) genotypes (CC) showed a major histopathological response with less than 10% residual vital tumor cells in 80%. The results support the role of the T393C polymorphism as a predictive molecular marker for tumor response to cisplatin/5-FU-based radiochemotherapy in esophageal cancer.

Successful management of esophageal perforation due to an aortic arch aneurysm replacement.

We present the successful management of an esophageal perforation after aortic arch aneurysm replacement in a 64-year-old patient. Four weeks after surgical repair of a perforated aortic arch aneurysm, a contained perforation of the thoracic esophagus on the prosthesis was detected. A subtotal esophagectomy and reconstruction by pull-up of the stomach together with the greater omentum and high intrathoracic esophagogastrostomy was performed. The aortic prosthesis was covered by omentum. After a prolonged postoperative course, the patient was discharged from the hospital on a full oral diet. She is well after 1 year without signs of infection.

Serosal penetration is an important prognostic factor for gastrointestinal stromal tumors.

Predicting the malignant potential of gastrointestinal stromal tumors (GISTs) remains difficult. We assessed the value of serosal penetration, an established prognostic factor in solid tumors, to determine the clinical outcome in patients with GISTs. From 1996-2002, 25 consecutive patients with GIST underwent surgical resection at our Department. The histopathological presence of serosal penetration was assessed to predict clinical outcome. In addition, the established histopathological classification system by Franquemont (modified by using the Ki-67 proliferation index), was applied to each study patient. A Ki-67 index > or =5% (p<0.001) and a mitotic rate > or =5/50 high-power fields (p<0.047) significantly correlated with a shorter survival, whereas a tumor size >5 cm (p=0.07) tended towards a worse prognosis. The survival of patient groups defined by Franquemont (p=0.03) were of prognostic relevance. The presence of serosal penetration significantly correlated (p<0.01) with a shorter survival. Our data suggest that the presence of serosal penetration is a negative prognostic factor for GISTs. Serosal penetration may become a useful additional parameter for the classification of the malignant potential of GISTs. Since our data are merely hypothesis-generating, serosal penetration should be evaluated in large prospective databases.

Comparative analysis of four histopathological classification systems to discriminate benign and malignant behaviour in gastrointestinal stromal tumors.

UNLABELLED: The prognostic value of the four most common histopathological classification systems in gastrointestinal stromal tumors (GISTs) was evaluated retrospectively. PATIENTS AND METHODS: Twenty-five consecutive patients with resected GIST and a follow-up of five years or more for surviving patients were included in this analysis. All the tumors were c-KIT (CD117) positive and were additionally re-evaluated for the number of mitoses per 50 high-power fields (HPF) and Ki-67 proliferation index. The four most commonly applied histopathological classification systems of the WHO, Franquemont (modified by using the Ki-67 proliferation index), Fletcher and Miettinen were applied to each patient. RESULTS: The survival of patient groups classified by Franquemont (p = 0.03) and the WHO (p = 0.031) were of prognostic relevance, while the grouping of patients by classifications according to both, Fletcher and Miettinen did not show a significant prognostic value. CONCLUSION: The classification systems of Franquemont (modified) or WHO appear to be advantageous for the evaluation of malignant potential and clinical outcome in patients with GISTs. Our data are merely hypothesis generating and should be validated in larger clinical studies.

Clinicopathologic and prognostic factors of young and elderly patients with esophageal adenocarcinoma: is there really a difference?

Evidence suggests a significant difference in the incidence, presentation, and outcome of young and elderly patients with esophageal adenocarcinoma. We aimed to compare clinicopathologic and prognostic factors of young and elderly patients with esophageal adenocarcinoma at a surgical department in Europe. From 1996 to 2006, 223 patients with a resectable esophageal adenocarcinoma were analyzed and divided in three groups: (i) patients 70 years (n = 52). Clinicopathological and prognostic factors were compared between these groups. The total number of patients with esophageal adenocarcinoma increased significantly. Although the total number of patients

Thoracoscopic enucleation of esophageal leiomyomas: a feasible and safe procedure.

In recent years, minimally invasive approaches have been introduced, providing thoracoscopic/laparoscopic techniques in the treatment of esophageal leiomyomas. We determined the technical feasibility and patient safety of thoracoscopic enucleation of esophageal leiomyomas by evaluation of 10 consecutive patients undergoing this procedure. For the surgical approach, a four-trocar access via the right pleural cavity in single-lung ventilation was chosen. All minimally invasive procedures were successfully completed without conversion to open surgery. Every tumor was completely resected without opening of the mucosa. No relevant intra- or postoperative complications were detected. These data suggest that thoracoscopic enucleation is a feasible and safe procedure for esophageal leiomyomas.

Association of COX-2 expression with corresponding active and chronic inflammatory reactions in Barrett's metaplasia and progression to cancer.

AIMS: Risk reduction for Barrett's cancer in individuals taking non-steroidal anti-inflammatory drugs has been reported. Cyclooxygenase (COX)-2, one of the inhibited enzymes, is putatively involved in Barrett's cancer pathogenesis. The aim of this study was to examine a possible association between COX-2 protein expression and the development and progression of the Barrett's metaplasia-dysplasia-carcinoma sequence and the type and degree of associated inflammatory reaction. METHODS AND RESULTS: Squamous epithelium, metaplastic, low-grade, high-grade dysplastic lesions and tumour tissue of 49 resection specimens from patients with Barrett's adenocarcinoma were immunohistochemically analysed. Active and chronic inflammatory reactions were classified according to the Updated Sydney System. Within the Barrett's sequence, a significant progressive increase in COX-2 expression was identified (P < 0.0001). The most significant differences were detected between squamous epithelium and Barrett's metaplasia (P < 0.001) and from low- to high-grade dysplasia (P < 0.0001). Active and chronic inflammation were significantly different between squamous epithelium and Barrett's metaplasia (P < 0.0001), but not during further progression in the sequence. CONCLUSIONS: Increasing COX-2 expression in Barrett's metaplasia is significantly associated with a change in the local inflammatory reaction, but not during further progression through dysplasia to cancer. This supports the potential of a chemoprevention strategy using COX-2 inhibitors independent of the extent and type of the inflammatory reaction in Barrett's oesophagus.

The increased angiotensin II (type 1) receptor density in myocardium of type 2 diabetic patients is prevented by blockade of the renin-angiotensin system.

AIMS/HYPOTHESIS: The angiotensin II (type 1) (AT1) receptor mediates many biological effects of the renin-angiotensin system (RAS), leading to remodelling of cardiac tissue. The present study was designed to analyse changes in the function and expression of the AT1 receptor as principal effector of the RAS in myocardium from type 2 diabetic patients compared with non-diabetic myocardium as control. In addition, we determined the effect of treatment with ACE inhibitors or AT1 receptor blockers on expression levels of the receptor in diabetic patients. METHODS: Gene expression of the AT1 receptor was analysed by quantitative RT-PCR and protein expression was determined by immunoblot analysis in human right atrial myocardium. We investigated functional coupling of the receptors by measuring contractility in isolated trabeculae stimulated with increasing concentrations of angiotensin II. RESULTS: Diabetic myocardium showed a significant increase in protein expression (170 +/- 16% of control) and median mRNA expression (186% of control) of the AT1 receptor. The additional receptors were functionally coupled, resulting in a stronger inotropic response upon stimulation with angiotensin II (89 +/- 5.5% vs 29 +/- 1.6% in controls), whereas receptor affinity was similar in both groups. However, myocardium from diabetic patients treated with ACE inhibitors or AT1 receptor blockers showed no increase in AT1 receptor expression. CONCLUSIONS/INTERPRETATION: AT1 receptor expression in myocardium of type 2 diabetic patients is dynamic, depending on the level of glycaemic control and the activity of the RAS. These findings could at least in part explain the strong therapeutic benefit of RAS inhibition in diabetic patients.

[Preoperative evaluation of prognostic factors in esophageal squamous cell cancer]. / Präoperative Erfassung von Prognosefaktoren beim Plattenepithelkarzinom des Osophagus.

Despite substantial improvements in the surgical therapy of esophageal squamous cell cancer, the prognosis still remains poor. This is mainly due to locally advanced tumors (T3-4, N+) or systemic metastases (M1) in the majority of patients at initial presentation. It is of the utmost importance to reliably detect relevant pretherapeutic prognostic indicators for optimal individual therapeutic strategies. Pretherapeutic prognostic indicators should therefore discriminate precisely between incurable and potentially curative disease. Preoperative or definitive multimodal treatment is increasingly being offered to patients with locally advanced tumors and opens a broad field for innovative techniques such as pretherapeutic molecular response prediction or early response detection by PET scan to further individualize and optimize treatment strategies.

[Adenocarcinoid of the appendix vermiformis]. / Adenokarzinoid der Appendix vermiformis.

Adenocarcinoids are rare tumors with histological features of both carcinoid tumor and adenocarcinoma. They show a more aggressive biological behaviour than conventional carcinoids. We report a case of a 64-years-old female patient with a diffuse infiltration of the appendicular wall by an adenocarcinoid. Due to the positive surgical margin and the tumor expansion a hemicolectomy was performed. There are no precise criteria to direct the operative choice between appendectomy and hemicolectomy. It is thought that appendectomy is sufficient in case of small tumors in the tip of the appendix. Patients with diffuse appendicular involvement require a more aggressive surgical therapy.