Kathrin Dellas

Prognostic impact of HIF-1alpha expression in patients with definitive radiotherapy for cervical cancer.

Purpose:To investigate the relationship between the hypoxia-inducible factor-(HIF-)1α expression in tumor tissue, tumor oxygenation and hemoglobin levels in patients with advanced cervical cancers prior to radiotherapy and the effect on clinical outcome.Patients and Methods:The investigation included 44 patients who underwent definitive radiotherapy for advanced cervical cancers between May 1995 and March 1999. Tumor biopsies were taken prior to treatment, and HIF-1α expression was determined by immunohistochemistry. In the same tumor area, tumor tissue oxygenation (pO2) was measured using the Eppendorf device.Results:The 5-year cancer-specific survival of all patients was 60%. Twelve of 44 tumor specimens were HIF-1α-negative with a significantly better 5-year survival (92 ± 8%) versus 32 patients who were HIF-1α-positive (45 ± 10%; p < 0.02). There was no correlation between HIF-1α expression and tumor oxygenation (p = 0.57 both for pO2 median and hypoxic fraction < 5 mmHg vs. HIF-1α expression). However, patients with hemoglobin levels < 11 g/dl showed elevated HIF-1α expression compared to patients with hemoglobin levels > 12.5 g/dl (p = 0.04). Furthermore, HIF-1α correlated with vascular endothelial growth factor expression (p = 0.002). In a multivariate Cox regression model, HIF-1α expression (relative risk [RR] = 7.5; p = 0.05) revealed an increased risk of tumor-related death.Conclusion:The study indicates, that endogenous tumor markers such as HIF-1α may serve as prognostic markers of clinical outcome concerning cervical cancer after primary radiotherapy.Ziel:Untersuchung möglicher Zusammenhänge zwischen der Expression des hypoxieinduzierbaren Faktors-(HIF-)1α in Tumorgewebe, der Tumoroxygenierung und dem Hämoglobinwert bei Patientinnen mit fortgeschrittenem Zervixkarzinom vor der Radiotherapie sowie der Auswirkungen dieser Parameter auf den klinischen Verlauf.Patienten und Methodik:Zwischen Mai 1995 und März 1999 wurden 44 Patientinnen eingeschlossen, die sich einer definitiven Radiatio eines fortgeschrittenen Zervixkarzinoms unterzogen. Vor Beginn der Therapie wurden Bioptate entnommen und die HIF-1α-Expression durch Immunhistochemie bestimmt. Außerdem wurde in derselben Tumorregion die Tumoroxygenierung (pO2) mit dem Eppendorf-Histographen gemessen.Ergebnisse:Das tumorspezifische 5-Jahres-Überleben betrug 60%. Zwölf von 44 Tumorproben waren HIF-1α-negativ mit einem signifikant besseren 5-Jahres-Überleben (92 ± 8%) gegenüber 32 Patientinnen mit positivem Nachweis einer HIF-1α-Expression (45 ± 10%; p < 0,02). Es konnte keine Korrelation zwischen der HIF-1α-Expression und der Tumoroxygenierung nachgewiesen werden (jeweils p = 0,57 für die Korrelation mit dem medianen pO2 und der hypoxischen Fraktion < 5 mmHg). Jedoch zeigten Patientinnen mit einem Hämoglobinwert < 11 g/dl eine erhöhte HIF-1α-Expression im Vergleich zu Patientinnen mit einem Hämoglobinwert > 12,5 g/dl (p = 0,04). Eine Korrelation wurde darüber hinaus zwischen einer HIF-1α- and einer VEGF-(„vascular endothelial growth factor“-)Expression (p = 0,002) nachgewiesen. Die multivariate Cox-Regression zeigte ein erhöhtes Risiko für einen tumorassoziierten Tod bei Patientinnen mit Nachweis einer HIF-1α-Expression (relatives Risiko [RR] = 7,5; p = 0,05).Schlussfolgerung:Die Untersuchungen deuten darauf hin, dass endogene Tumormarker wie HIF-1α als prognostische Parameter für den klinischen Verlauf bei Patientinnen mit Zervixkarzinom nach einer definitiven Radiotherapie von Bedeutung sein können.

PREOPERATIVE RADIOTHERAPY OF ADVANCED RECTAL CANCER WITH CAPECITABINE AND OXALIPLATIN WITH OR WITHOUT CETUXIMAB: A POOLED ANALYSIS OF THREE PROSPECTIVE PHASE I-II TRIALS

PURPOSE A pooled analysis of three prospective trials of preoperative radiochemotherapy (RCT) for rectal cancer by using oxaliplatin and capecitabine with or without cetuximab was performed to evaluate the impact of additional cetuximab on pathologic complete response (pCR) rates and tumor regression (TRG) grades. METHODS AND MATERIALS Of 202 patients, 172 patients met the inclusion criteria (primary tumor stage II/III, M0). All patients received concurrent RCT, and 46 patients received additional cetuximab therapy. A correlation of pretreatment clinicopathologic factors and cetuximab treatment with early pCR rates (TRG > 50%) was performed with univariate and multivariate analyses. Toxicity data were recorded for all patients. RESULTS Of 172 patients, 24 (14%) patients achieved a pCR, and 84 of 172 (71%) patients showed a TRG of >50% in the surgical specimen assessment after preoperative treatment. Age, gender, and T/N stages, as well as localization of the tumor, were not associated with pCR or good TRG. The pCR rate was 16% after preoperative RCT alone and 9% with concurrent cetuximab therapy (p = 0.32). A significantly reduced TRG of >50% was found after RCT with cetuximab compared to RCT alone (p = 0.0035). This was validated by a multivariate analysis with all available clinical factors (p = 0.0037). Acute toxicity and surgical complications were not increased with additional cetuximab. CONCLUSIONS Triple therapy with RCT and cetuximab seems to be feasible, with no unexpected toxicity. Early response assessment (TRG), however, suggests subadditive interaction. A longer follow-up (and finally randomized trials) is needed to draw any firm conclusions with respect to local and distant failure rates.

Biomarkers for Cetuximab-Based Neoadjuvant Radiochemotherapy in Locally Advanced Rectal Cancer

Purpose: Phase II trials in locally advanced rectal cancer have shown that cetuximab-based neoadjuvant radiochemotherapy is feasible but without an improvement in complete pathologic response rates. Our goal was to identify patients who would benefit from cetuximab-based neoadjuvant chemoradiation measuring gene expression levels of proteins involved in tumor growth [endothelial growth factor receptor (EGFR)], angiogenesis [VEGF, VEGF receptors 1 and 2 (VEGFR1, VEGFR2)], DNA repair [excision repair cross-complementing 1 (ERCC1)], and drug metabolism [thymidylate synthetase (TS)]. We also determined mutation status of KRAS and BRAF. Experimental Design: This study was carried out on 130 patients with locally advanced rectal cancer who were enrolled in 4 different phase II clinical trials, using cetuximab-based chemoradiation. Tumor tissues were obtained before neoadjuvant and at surgical therapy. After microdissection, intratumoral gene expression levels and KRAS/BRAF mutation status were analyzed. Results: A significant decrease of TS, VEGFR1, and VEGFR2 gene expression was seen following neoadjuvant therapy (P < 0.03). High pretreatment VEGF gene expression levels were associated with nonresponse (P = 0.070). KRAS mutations were found in 42% and mutant KRAS (KRAS mt) was significantly associated with pathologic nonresponse (P = 0.037). In patients with wild-type KRAS (KRAS wt), low EGFR was significantly associated with higher nonresponse and VEGF mRNA expressions were associated with complete pathologic response (P = 0.012; P = 0.06). KRAS transversion (KRAS tv) was associated with tumor regression: nonresponse was more common in patients with KRAS tv than with KRAS wt (P = 0.007). BRAF V600E mutations were not detected in any of the patients. Conclusion: This study suggests that pretreatment intratumoral EGFR and VEGF mRNA expression levels as well as KRAS mutation status are predictive markers of pathologic response to neoadjuvant cetuximab-based chemoradiation in locally advanced rectal cancer. Clin Cancer Res; 17(10); 3469–77. ©2011 AACR.

EGF61 polymorphism predicts complete pathologic response to cetuximab-based chemoradiation independent of KRAS status in locally advanced rectal cancer patients

Background: Cetuximab has shown significant clinical activity in metastatic colon cancer. However, cetuximab-containing neoadjuvant chemoradiation has not been shown to improve tumor response in locally advanced rectal cancer patients in recent phase I/II trials. We evaluated functional germline polymorphisms of genes involved in epidermal growth factor receptor pathway, angiogenesis, antibody-dependent cell-mediated cytotoxicity, DNA repair, and drug metabolism, for their potential role as molecular predictors for clinical outcome in locally advanced rectal cancer patients treated with preoperative cetuximab-based chemoradiation. Methods: 130 patients (74 men and 56 women) with locally advanced rectal cancer (4 with stage II, 109 with stage III, and 15 with stage IV, 2 unknown) who were enrolled in phase I/II clinical trials treated with cetuximab-based chemoradiation in European cancer centers were included. Genomic DNA was extracted from formalin-fixed paraffin-embedded tumor samples and genotyping was done by using PCR-RFLP assays. Fishers exact test was used to examine associations between polymorphisms and complete pathologic response (pCR) that was determined by a modified Dworak classification system (grade III vs. grade IV: complete response). Results: Patients with the epidermal growth factor (EGF) 61 G/G genotype had pCR of 45% (5/11), compared with 21% (11/53) in patients heterozygous, and 2% (1/54) in patients homozygous for the A/A allele (P < 0.001). In addition, this association between EGF 61 G allele and pCR remained significant (P = 0.019) in the 59 patients with wild-type KRAS. Conclusion: This study suggested EGF A+61G polymorphism to be a predictive marker for pCR, independent of KRAS mutation status, to cetuximab-based neoadjuvant chemoradiation of patients with locally advanced rectal cancer. Clin Cancer Res; 17(15); 5161–9. ©2011 AACR.

Immunohistochemical Detection of HIF-1α and CAIX in Advanced Head-and-Neck Cancer@@@Immunhistochemischer Nachweis von HIF-1α und CAIX in fortgeschrittenen Kopf-Hals-Tumoren. Prognostische Rolle und Korrelation mit Tumormarkern und Tumoroxygenierungsparametern: Prognostic Role and Correlation with Tumor Markers and Tumor Oxygenation Parameters

Background:Tumor hypoxia has an impact on the outcome of cancer patients treated with radiotherapy. The validity of endogenous markers such as hypoxia-inducible factor-1α (HIF-1α) and carbonic anhydrase isozyme IX (CAIX) to detect therapeutically relevant levels of hypoxia within tumors is controversially discussed. Furthermore, the association of these hypoxia markers with tumor markers or tumor oxygenation parameters is of importance for understanding the relationship between the different factors.Patients and Methods:Tumor tissue sections of 34 patients with advanced head-and-neck cancer treated with radio(chemo)therapy were assessed by immunohistochemistry for the expression of HIF-1α and CAIX. The relationships of both markers with tumor oxygenation parameters, molecular factors like P53, OPN, VEGF, VHL, survivin, and Ki67 levels, and clinical parameters were studied.Results:Bivariate analysis showed a significant correlation of HIF-1α expression with high P53 and high OPN expression, high serum VEGF levels, and low VHL and low Ki67 expression. The CAIX expression was inversely correlated with pH value and directly correlated with T-stage. However, no correlation was found between HIF-1α and CAIX expression.Neither in a univariate Cox proportional hazard regression nor in a Kaplan-Meier analysis did expression of HIF-1α or CAIX have a significant impact on clinical outcome. However, in a Kaplan-Meier analysis, the combination of both factors showed that patients with intratumoral overexpression of either HIF-1α or CAIX or both markers died on average 2 years earlier than patients whose tumors had low expression of both factors (p < 0.05).Conclusion:Expression of HIF-1α and CAIX was correlated with different tumor parameters. Only combined HIF-1α and CAIX expression was significantly predictive of patients’ overall survival.Hintergrund:Hypoxie in Tumoren hat einen Einfluss auf die Prognose von Tumorpatienten, die eine Strahlentherapie erhielten. Der Einsatz von endogenen Markern wie hypoxieinduzierbarem Faktor-1α (HIF-1α) und Carboanhydrase-Isoenzym IX (CAIX) zur Identifizierung therapierelevanter hypoxischer Tumorbereiche wird jedoch kontrovers diskutiert. Die Untersuchung der Assoziation von Tumormarkern und tumorrelevanten Oxygenierungsparametern ist deshalb von wesentlicher Bedeutung für das Verständnis der Beziehung dieser biologischen Indikation.Patienten und Methodik:An Tumorgewebeschnitten von 34 Patienten mit radio(chemo)therapierten fortgeschrittenen Kopf-Hals-Tumoren wurde immunhistochemisch die Expression von HIF-1α und CAIX untersucht. Die Expression beider Marker wurde mit Tumoroxygenierungsparametern, der Expression molekularer Faktoren wie P53, OPN, VEGF, VHL, Survivin und Ki67 sowie klinischen Parametern in Beziehung gesetzt.Ergebnisse:Bivariate Analysen zeigten eine signifikante Korrelation zwischen einer HIF-1α-Expression und einer hohen P53- und OPN-Expression, einem hohen Serum-VEGF-Gehalt sowie einer geringeren VHL- und Ki67-Expression. Eine hohe CAIX-Expression korrelierte invers mit dem pH-Wert und direkt mit dem T-Stadium. Zwischen der HIF-1α- und CAIX-Expression wurde keine Korrelation nachgewiesen.Mittels univariater Cox-Regressions- bzw. Kaplan-Meier-Analyse zeigte weder die HIF-1α- noch die CAIX-Expression einen signifikanten Einfluss auf das Überleben. Die Kombination der beiden Faktoren ergab dagegen in der Kaplan-Meier-Analyse, dass Patienten mit intratumoraler Überexpression von HIF-1α oder CAIX oder beiden Markern durchschnittlich 2 Jahre früher verstarben als Patienten, deren Tumoren eine geringe Expression beider Faktoren aufwiesen (p < 0,05).Schlussfolgerung:Die Expression von HIF-1α und CAIX korrelierte mit verschiedenen Tumorparametern. Erst die Kombination der Marker HIF-1α und CAIX zeigte einen signifikanten prädiktiven Einfluss auf das Gesamtüberleben von Patienten mit Kopf-Hals-Tumoren nach einer Radio(chemo)therapie.

Preoperative Chemoradiation Therapy With Capecitabine/ Oxaliplatin and Cetuximab in Rectal Cancer: Long-Term Results of a Prospective Phase 1/2 Study

PURPOSE We have previously shown that the addition of cetuximab to chemoradiation therapy failed to improve complete response rates (pCR) in rectal cancer. Here we report the long-term results of the cetuximab added to preoperative radiation therapy with capecitabine and oxaliplatin (CET-CAPOX-RT) phase 1/2 study that evaluated preoperative chemoradiation with cetuximab, capecitabine, and oxaliplatin in patients with rectal cancer. METHODS AND MATERIALS The median follow-up was 63 months (range, 5-73 months). Sixty patients were enrolled; 3 patients were excluded due to protocol violation, and 4 died before surgery. Total mesorectal excision was performed in 53 patients, in 85% (n=45) with curative intention (M0-status). Secondary end points including overall survival (OS) disease-free survival (DFS) and cancer-specific survival (CSS) were calculated. The prognostic value of KRAS mutation status was also assessed. RESULTS Histopathological examination confirmed ypUICC stages 0 (n=4; pCR), I (n=17), II (n=10), III (n=14), and IV (n=8). For patients who underwent surgery (n=53), OS at 1, 3, and 5 years was 88.7%, 83%, and 75.5%, respectively, whereas CSS rates were 94.1%, 88.1%, and 78.1%, respectively. In the 45 patients who were treated with curative intent (M0), the OS rates at 1, 3, and 5 years were 91.1%, 88.9%, and 86.7%, respectively; whereas CSS rates were 97.6%, 95.2%, and 90.3%, respectively; and DFS rates were 90.7%, 88.3%, and 88.3%, respectively. We did not find any locoregional failure in patients with M0-status (n=45). Chronic toxicity was rare. KRAS mutations, as detected in 33.3%, showed no correlation with the clinicopathological parameters nor significance for either OS (P=.112), CSS (P=.264), or DFS (P=.565). CONCLUSIONS Taken together, chemoradiation therapy combined with cetuximab is safe, feasible, and offers excellent survival rates. KRAS mutation status was not a predictive factor. Importantly, lack of improvement in pCR rate did not translate to poor survival in our clinical trial.

Was muss ich tun, um eine klinische Studie starten zu können?

„Was muss ich tun, um meine klinische Studie starten zu konnen?“ ist eine Frage, die haufig von Arzten gestellt wird, die in die medizinische Forschung einsteigen. Auch fur viele studienerfahrene Arzte und Forscher stellt die Beantwortung dieser Frage oftmals eine Herausforderung dar, da komplexe und sich andernde juristische und regulatorische Aspekte die Anforderungen an eine klinische Studie bestimmen. In diesem Beitrag wollen wir Ihnen einen Leitfaden fur die Planungsphase Ihrer klinischen Studie an die Hand geben.

Margins! Margins. Margins? How Important Is Margin Status in Breast-Preserving Therapy?

Margin status is surely a prognostic factor in patients undergoing breast-conserving therapy, but its impact is probably overestimated in case of adequate adjuvant radiotherapy. Radiotherapy improves local control after excision of the primary tumor in all subgroups of patients. There is, in contrast, no evidence that a certain margin width or a re-resection improves local control.