贝伐珠单抗联合化疗治疗转移性结直肠癌的近期效果及安全性

目的 研究贝伐珠单抗（bevacizumab,Bev）联合化疗治疗转移性结直肠癌的近期疗效和安全性.方法 对43例接受贝伐珠单抗联合化疗治疗的晚期结直肠癌患者进行回顾分析,评价联合治疗的近期疗效及不良反应.结果 43例患者中部分缓解（PR）17例,疾病稳定（SD）19例,疾病进展（PD）7例;中位无进展生存（PFS）为10.3个月.3～4度不良反应主要为白细胞和粒细胞减少及恶心、呕吐.与贝伐珠单抗相关的不良反应为蛋白尿、高血压、鼻出血、经血增加、肠道出血、肠穿孔及静脉血栓等.结论 贝伐珠单抗联合化疗治疗晚期结直肠癌近期疗效较好,不良反应可耐受,远期疗效有待进一步观察.     

Microvessel density and endothelial cell proliferation levels in colorectal liver metastases from patients given neo‐adjuvant cytotoxic chemotherapy and bevacizumab

The treatment of patients with colorectal liver metastasis has improved significantly and first line therapy is often combined chemotherapy and bevacizumab, although it is unknown who responds to this regimen. Colorectal liver metastases grow in different histological growth patterns showing differences in angiogenesis. To identify possible response markers, histological markers of angiogenesis were assessed. Patients who underwent resection of colorectal liver metastasis at Rigshospitalet, Copenhagen, Denmark from 2007 to 2011 were included (n = 254) including untreated and patients treated with chemotherapy or chemotherapy plus bevacizumab. The resected liver metastases were characterised with respect to growth pattern, endothelial and tumour cell proliferation as well as microvessel density and tumour regression. Tumour regression grade of liver metastases differed significantly between untreated/chemotherapy treated patients in comparison to chemotherapy plus bevacizumab treated patients (both p < 0.0001). Microvessel density was decreased in liver metastases from patients treated with bevacizumab in comparison to those from untreated/chemotherapy‐treated patients (p = 0.006/p = 0.002). Tumour cell proliferation assessed by Ki67 expression correlated to a shorter recurrence free survival in the total patient cohort. In conclusion, liver metastases from patients treated with neo‐adjuvant chemotherapy and bevacizumab had significantly lower microvessel densities and tumour regression grades when compared to liver metastases from untreated or chemotherapy treated patients. This may indicate that bevacizumab treatment results in altered vascular biology and tumour viability, with possible tumour reducing effect.     

Pathological responses after angiogenesis or EGFR inhibitors in metastatic colorectal cancer depend on the chemotherapy backbone

Background:

Optimal preoperative treatment before colorectal cancer metastases (CRCM) resection remains unclear. This study evaluated pathological responses (pR) in CRCM resected after chemotherapy alone or combined with angiogenesis or epidermal growth factor receptor (EGFR) inhibitors.

Methods:

Pathological response was retrospectively evaluated on 264 resected metastases from 99 patients. The proportion of responding metastases after different preoperative treatments was reported and compared. Patient''s progression-free survival (PFS) and overall survival (OS) were compared based on pR.

Results:

The combination of anti-angiogenics with oxaliplatin-based chemotherapy resulted in more pR than when they were combined with irinotecan-based chemotherapy (80% vs 50% P<0.001). Inversely, the combination of EGFR inhibitors with oxaliplatin-based chemotherapy seemed to induce fewer pR than when they were combined with irinotecan-based treatment (53% vs 72% P=0.049). Overall survival at 5 years was improved for patients with a pR in all resected metastases compared with those who did not achieve a pR (68.5% vs 32.6% P=0.023) and this response was the only factor predicting OS in a multivariate analysis.

Conclusion:

The chemotherapy partner combined with angiogenesis or EGFR inhibitors influenced pR in resected CRCM. In our exploratory analysis anti-angiogenic/oxaliplatin-based regimens and anti-EGFR/irinotecan-based regimens were associated with the highest pR. Prospective randomised trials should be performed to validate these observations.     

First-line XELOX plus bevacizumab followed by XELOX plus bevacizumab or single-agent bevacizumab as maintenance therapy in patients with metastatic colorectal cancer: the phase III MACRO TTD study

Purpose.

The aim of this phase III trial was to compare the efficacy and safety of bevacizumab alone with those of bevacizumab and capecitabine plus oxaliplatin (XELOX) as maintenance treatment following induction chemotherapy with XELOX plus bevacizumab in the first-line treatment of patients with metastatic colorectal cancer (mCRC).

Patients and Methods.

Patients were randomly assigned to receive six cycles of bevacizumab, capecitabine, and oxaliplatin every 3 weeks followed by XELOX plus bevacizumab or bevacizumab alone until progression. The primary endpoint was the progression-free survival (PFS) interval; secondary endpoints were the overall survival (OS) time, objective response rate (RR), time to response, duration of response, and safety.

Results.

The intent-to-treat population comprised 480 patients (XELOX plus bevacizumab, n = 239; bevacizumab, n = 241); there were no significant differences in baseline characteristics. The median follow-up was 29.0 months (range, 0–53.2 months). There were no statistically significant differences in the median PFS or OS times or in the RR between the two arms. The most common grade 3 or 4 toxicities in the XELOX plus bevacizumab versus bevacizumab arms were diarrhea, hand–foot syndrome, and neuropathy.

Conclusion.

Although the noninferiority of bevacizumab versus XELOX plus bevacizumab cannot be confirmed, we can reliably exclude a median PFS detriment >3 weeks. This study suggests that maintenance therapy with single-agent bevacizumab may be an appropriate option following induction XELOX plus bevacizumab in mCRC patients.     

The state of regional therapy in the management of metastatic colorectal cancer to the liver

Colorectal cancer (CRC) is one of the leading causes of cancer-related mortality in the United States. Most colorectal cancer patients die from advanced disease, and two-thirds of CRC deaths are due to liver metastases. Liver resection provides the best curative option for patients with colorectal liver metastases (CRLM), yet only 20% of those patients are eligible for liver metastases resection for curative intent. Loco-regional treatment of CRLM may provide additional benefits in terms of down-staging for resection and prolonged hepatic disease control. This review focusses on hepatic arterial infusion, radioembolization and chemoembolization.     

A double-blind, randomized, placebo-controlled, phase 2 study of maintenance enzastaurin with 5-fluorouracil/leucovorin plus bevacizumab after first-line therapy for metastatic colorectal cancer

BACKGROUND:

Enzastaurin and bevacizumab have demonstrated synergistic antitumor effects and, in phase 1 studies, the combination was well tolerated. This phase 2 study assessed enzastaurin with 5‐fluorouracil/leucovorin plus bevacizumab as maintenance therapy for metastatic colorectal cancer (MCRC).

METHODS:

Patients with locally advanced or MCRC and stable or responding disease after completing 6 cycles of first‐line chemotherapy randomly received a loading dose of enzastaurin 1125 mg, followed by 500 mg/d subsequent doses or placebo. Both arms received 5‐fluorouracil/leucovorin (leucovorin 400 mg/m² intravenously [IV], 5‐fluorouracil 400‐mg/m² bolus, 5‐fluorouracil 2400 mg/m² IV) plus bevacizumab 5 mg/kg IV, every 2 weeks. The primary endpoint was progression‐free survival (PFS), from randomization. Overall survival (OS) and PFS were also assessed from start of first‐line therapy. Enrollment was stopped, and the final analysis was conducted after 73 PFS events.

RESULTS:

Fifty‐eight patients were randomized to enzastaurin and 59 to placebo. For the enzastaurin and placebo arms, respectively, the median cycles received were 9 and 10, and the median PFS was 5.8 and 8.1 months (hazard ratio [HR], 1.35; 95% confidence interval [CI], 0.84‐2.16; P = .896). Median OS was not calculable because of high censoring (77.6% enzastaurin; 91.5% placebo). The median PFS from start of first‐line therapy was 8.9 months for enzastaurin and 11.3 months for placebo (HR, 1.39; 95% CI, 0.86‐2.23; P = .913). More enzastaurin patients developed thrombosis or embolism compared with placebo (15.8% and 1.7%; P = .008). One possibly enzastaurin‐related death occurred because of arrhythmia.

CONCLUSIONS:

Enzastaurin combined with bevacizumab‐based therapy is tolerable, but does not improve PFS during maintenance therapy in patients with MCRC compared with bevacizumab‐based therapy alone. Cancer 2012. © 2011 American Cancer Society.     

Serial profiling of circulating tumor DNA for optimization of anti‐VEGF chemotherapy in metastatic colorectal cancer patients

Understanding the molecular changes in tumors in response to anti‐VEGF chemotherapy is crucial for optimization of the treatment strategy for metastatic colorectal cancer. We prospectively investigated changes in the amount and constitution of circulating tumor DNA (ctDNA) in serial peripheral blood samples during chemotherapy. Sixty‐one plasma samples taken at different time points (baseline, remission, and post‐progression) and pre‐treatment tumor samples were collected from 21 patients who received bevacizumab‐containing first‐line chemotherapy. Extracted DNA was sequenced by next‐generation sequencing using a panel of 90 oncogenes. Candidate ctDNAs in plasma were validated using mutational data from matching tumors. ctDNAs encoding one to six trunk mutations were found in all 21 cases, and the mutant allele frequency (MAF) was distributed over a wide range (1‐89%). Significant decreases in the MAF at remission and increases in the MAF after progression were observed (p < 0.001). Reduction in the MAF to below 2% in the remission period was strongly associated with better survival (16.6 vs. 32.5 months, p < 0.001). In two cases, mutations (in CREBBP and FBXW7 genes) were newly detected in ctDNA at a low frequency of around 1% in the post‐progression period. The use of ctDNA allows elucidation of the tumor clonal repertoire and tumor evolution during anti‐VEGF chemotherapy. Changes in ctDNA levels could be useful as predictive biomarkers for survival. Mutations newly detected in ctDNA in the late treatment period might reveal the rise of a minor tumor clone that may show resistance to anti‐VEGF therapy.     

A phase I study of axitinib (AG-013736) in combination with bevacizumab plus chemotherapy or chemotherapy alone in patients with metastatic colorectal cancer and other solid tumors

BackgroundAxitinib and bevacizumab are targeted therapies against the vascular endothelial growth factor pathway.MethodsPatients with previously treated solid tumors received axitinib (starting dose 5 mg twice daily) combined with FOLFOX plus bevacizumab (1, 2, or 5 mg/kg, cohorts 1–3, respectively), FOLFIRI (cohort 4), or FOLFOX (cohort 5). Safety and pharmacokinetics were assessed.ResultsThirty patients were enrolled (n = 16, 8, and 6 for cohorts 1–3, 4, and 5, respectively). Plasma concentrations and pharmacokinetic (PK) parameters were similar when drugs were administered alone and in various combinations. Most treatment-emergent adverse events (AEs) were mild to moderate and clinically manageable (most common: nausea, fatigue, diarrhea, anorexia, hypertension). Two of the four patients receiving axitinib with FOLFOX plus 5 mg/kg bevacizumab experienced dose-limiting toxicity (DLT) of inability to resume treatment for 14 days following treatment interruption (associated AE: hypertension); the maximum tolerated dose of bevacizumab in this combination was 2 mg/kg. No DLTs occurred with axitinib plus FOLFIRI or FOLFOX. Ten patients had RECIST-confirmed partial tumor responses (objective response rate: 33.3%).ConclusionAxitinib is well tolerated in combination with FOLFOX, FOLFIRI, or FOLFOX plus 2 mg/kg bevacizumab. PK interactions appear to be absent.     

Clinical impact of c‐MET expression and genetic mutational status in colorectal cancer patients after liver resection

c‐MET is implicated in the pathogenesis and growth of a wide variety of human malignancies, including colorectal cancer (CRC). The aim of the present study was to clarify the association between c‐MET expression and tumor recurrence in CRC patients after curative liver resection, and to evaluate concordance in c‐MET expression and various mutations of KRAS, BRAF and PIK3CA between primary CRC and paired liver metastases. A cohort of patients was tested for c‐MET immunoreactivity (i.e. immunohistochemistry [IHC]) and KRAS, BRAF and PIK3CA mutations. Analyses were performed both on primary tumors and paired liver metastases, and the association between IHC and mutations results were assessed. A total of 108 patients were eligible. A total of 53% of patients underwent simultaneous resection of primary tumors and metastases, and the others underwent metachronous resection. Levels of concordance between primary tumors and metastases were 65.7%, 87.7%, 100% and 95.2% for c‐MET, KRAS, BRAF and PIK3CA, respectively. High levels of c‐MET expression (c‐MET‐high) in the primary tumors were observed in 52% of patients. Relapse‐free survival was significantly shorter for patients with c‐MET‐high primary tumors (9.7 months) than for those with c‐MET‐low primary tumors (21.1 months) (P = 0.013). These results suggest that a high level of genetic concordance in KRAS, BRAF and PIK3CA between primary tumors and liver metastases, and c‐MET‐high in the primary tumors were associated with shorter relapse‐free survival after hepatic metastasectomy.     

孚贝联合肝动脉灌注治疗大肠癌肝转移的临床观察

为研究孚贝 (卡莫氟 )联合肝动脉灌注对大肠癌肝转移疗效及不良反应 ,对 40例不能手术切除的肝转移患者行大肠癌根治术加孚贝联合肝动脉灌注化疗和肝动脉加门静脉灌注化疗。全部患者随机分为两组 ,观察组 :孚贝联合肝动脉灌注化疗 2 0例 ;对照组 :肝动脉加门静脉灌注化疗 2 0例中 15例合格病例。观察组肝转移灶CR 1例 ,PR12例 ,近期有效率 65 0 % ( 13 /2 0 )。对照组CR 1例 ,PR 9例 ,近期有效率 66 7% ( 10 /15 )。 1、2、5年生存率观察组分别为 90 0 % ( 18/2 0 )、65 0 % ( 13 /2 0 )、2 5 0 % ( 5 /2 0 ) ;对照组为 93 3 % ( 14 /15 )、66 7% ( 10 /15 )、2 6 7% ( 4 /15 )。初步研究结果提示 ,口服孚贝联合肝动脉灌注化疗是治疗大肠癌肝转移的有效方法     

Retrospective review of mitomycin C use as third‐line chemotherapy in metastatic colorectal cancer

The aim of this review was to determine the therapeutic value of the combination of mitomycin C with either infusional 5‐fluorouracil or oral capecitabine in metastatic colorectal cancer when used as third‐line treatment or beyond in the setting of routine clinical practice. We retrospectively reviewed 18 patients with advanced colorectal cancer who received this combination at our institution after the failure of two lines of prior treatment. All the patients were assessable for toxicity and survival and 14 for tumor response. The median age of the patients was 61 (range 39–78). Of these, 72% were male and 78% had Eastern Cooperative Oncology Group performance status 0 or 1. Eighty nine percent of the patients had metastatic involvement of the liver and five patients had at least three sites of metastatic involvement. All patients had received at least two lines of chemotherapy and had progressed on an oxaliplatin‐containing regimen. Most of the patients had previously received an irinotecan‐containing regimen, and a third had received prior biological agents. Overall, none of the patients achieved either complete or partial responses. Two patients (11%) achieved stable disease and 12 patients (67%) had progressive disease. The median progression‐free survival was 2.7 months (range 0.5–8.8) and the median overall survival was 5.4 months (range 1.3–31.2). This chemotherapy regimen was well tolerated with an acceptable toxicity profile. The results of our review confirm the low efficacy of combination mitomycin C in heavily pretreated Australian patients with advanced colorectal cancer. This review confirms that it has no role after two lines of modern combination chemotherapy regimens and recommends that focus should be placed on investigating newer agents for good performance status patients progressing after these treatments.     

Pharmacokinetic parameters from 3-Tesla DCE-MRI as surrogate biomarkers of antitumor effects of bevacizumab plus FOLFIRI in colorectal cancer with liver metastasis

Bevacizumab (BV) is an antivascular endothelial growth factor antibody. When administered with other chemotherapeutic drugs, BV-combined regimens prolong survival of colorectal cancer patients. We conducted a phase II trial to confirm the pharmacokinetic parameters from 3-Tesla dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) as surrogate biomarkers of BV + FOLFIRI regimen efficacy in colorectal cancer with liver metastases. DCE-MRI was performed before treatment, on the seventh day after first treatment and every 8 weeks thereafter using a 3-Tesla MRI system. DCE-MRI parameters-area under the contrast concentration versus time curve at 90 and 180 s (AUC90 and AUC180, respectively) after contrast injection, and volume transfer constant of contrast agents (K(trans) and K(ep) ) were calculated from liver metastases. Fifty-eight liver metastases were analyzed. Univariate analysis revealed that a decrease in K(trans) ratios (ΔK(trans) ), K(ep) ratios (ΔK(ep) ), AUC90 ratios (ΔAUC90) and AUC180 ratios (ΔAUC180) correlated with higher response (all p < 0.0001) and longer time to progression (TTP) (ΔK(trans) : p = 0.001; ΔK(ep) : p = 0.004; ΔAUC90: p = 0.006; ΔAUC180: p < 0.0001). Multivariate analysis showed that ΔAUC180 was correlated with higher response (p = 0.009), and ΔK(trans) and ΔAUC180 were correlated with longer TTP (ΔK(trans) : p = 0.001; ΔAUC180: p = 0.024). ΔK(trans) and ΔAUC180 are pharmacodynamic biomarkers of the blood perfusion of BV + FOLFIRI. Our data suggest that ΔK(trans) and ΔK(ep) can predict response to chemotherapy at 1 week. Changes in 3-Tesla DCE-MRI parameters confirmed the potential of these biomarkers of blood perfusion as surrogate predictors of response and TTP.     

Effect of the vascular endothelial growth factor receptor-2 antibody DC101 plus gemcitabine on growth,metastasis and angiogenesis of human pancreatic cancer growing orthotopically in nude mice

Vascular endothelial growth factor (VEGF) is the major pro-angiogenic factor for most tumors. VEGF expression has been shown to be associated with a poor prognosis in human pancreatic cancer. The purpose of our study was to determine the effect of blockade of VEGF receptor-2 activity with or without gemcitabine on tumor growth and metastasis in an orthotopic model of human pancreatic cancer in nude mice. Therapy with gemcitabine or DC101, a VEGF receptor-2 antibody, resulted in a significant reduction of primary pancreatic tumor growth compared to untreated controls. The combination of DC101 and gemcitabine inhibited primary pancreatic tumor growth and lymphatic metastasis to a greater degree than either agent alone. Treatment with DC101 decreased vessel counts and increased the area of hypoxic tumor tissue compared to controls. Immunofluorescent double staining for apoptotic endothelial cells demonstrated a significant increase in the number apoptotic endothelial cells 24 days after initiation of therapy with DC101 plus gemcitabine. DC101 plus gemcitabine also increased tumor cell death and decreased tumor cell proliferation in pancreatic tumors. These findings indicate that blockade of VEGF receptor activation interferes with the survival of tumor endothelial cells, resulting in a reduction of primary pancreatic tumor growth in nude mice. Furthermore, the data demonstrate that anti-VEGF receptor-2 therapy potentiates the tumoricidal effect of gemcitabine in this model. Anti-VEGF receptor-2 therapy in combination with gemcitabine may be a novel therapeutic approach for advanced pancreatic cancer.     

A randomized phase III trial on maintenance treatment with bevacizumab alone or in combination with erlotinib after chemotherapy and bevacizumab in metastatic colorectal cancer: the Nordic ACT Trial

BackgroundThe main objective was to study the effect on progression-free survival (PFS) of adding erlotinib to bevacizumab as maintenance treatment following chemotherapy and bevacizumab as first-line treatment of metastatic colorectal cancer (mCRC).Patients and methodsPatients with untreated mCRC received doublet chemotherapy + bevacizumab during 18 weeks and those without tumor progression were eligible for randomization to bevacizumab + erlotinib (arm A) or bevacizumab alone (arm B), until progression or unacceptable toxic effect.ResultsOf the 249 patients enrolled, 80 started maintenance treatment in arm A and 79 in arm B. The rate of any grade 3/4 toxic effect was 53% in arm A and 13% in arm B. Median PFS was 5.7 months in arm A and 4.2 months in arm B (HR = 0.79; 95% confidence interval 0.55–1.12; P = 0.19). Overall survival (OS) from start of induction chemotherapy was 26.7 months in the randomized population, with no difference between the two arms.ConclusionsThe addition of erlotinib to bevacizumab as maintenance treatment after first-line chemotherapy in mCRC did not improve PFS significantly. On-going clinical and translational studies focus on identifying subgroups of patients that may benefit from erlotinib in the maintenance setting.Clinical Trials numberNCT00598156.