First clinical experience of orally active epidermal growth factor receptor inhibitor combined with simplified FOLFOX6 as first-line treatment for metastatic colorectal cancer

GRECCAR 8: impact on survival of the primary tumor resection in rectal cancer with unresectable synchronous metastasis: a randomized multicentre study

Background

A majority of patients with rectal cancer and metastasis are not eligible to curative treatment because of an extensive and unresectable metastatic disease. Primary tumor resection is still debated in this situation. Rectal surgery treats or prevents the symptoms and avoids the risk of acute complications related to the primary tumor. Several studies on colorectal cancers seem to show interesting results in terms of survival in favor to the resection of the primary tumor. To date, no randomized trial or even a prospective study has assessed the impact of primary tumor resection on overall survival in patients with colorectal cancer with unresectable metastasis. All published studies were retrospective and included colon and rectal cancers. Rectal cancer is associated with specific problems related to the rectal surgery. Surgery is more complex, and may be source of more morbidity and postoperative functional dysfunctions (stoma, digestive, sexual, urinary) than colic surgery. On the other hand, symptoms related to the progression of rectal tumor are often very disabling: pain, rectal syndrome.

Methods/Design

GRECCAR 8 is a multicentre randomized open-label controlled trial aimed to evaluate the impact on survival of the primary tumor resection in rectal cancer with unresectable synchronous metastasis. Patients must undergo upfront systemic chemotherapy for at least 4 courses before inclusion. Patients with progressive metastatic disease during upfront chemotherapy will be excluded from the study. Patients will be randomly assigned in a 1:1 ratio to Arm A: primary tumor resection followed by systemic chemotherapy versus Arm B: systemic chemotherapy alone. Primary endpoint will be overall survival measured from the date of randomization to the date of death or to the end of follow-up (2 years). Secondary endpoints will include progression-free survival, quality of life, toxicity of chemotherapy, response of the primary tumor and metastatic disease to chemotherapy, postoperative morbidity and mortality, rate of patient not eligible for postoperative chemotherapy (arm A), primary tumor related complications and rate of emergency surgery (arm B). The number of patients needed is 290.

Trial registration

ClinicalTrial.gov: NCT02314182

Laparoscopic surgery for palliative resection of the primary tumor in incurable stage IV colorectal cancer

BACKGROUND

The purpose of the study was to evaluate the feasibility and efficacy of laparoscopic palliative resection in patients with incurable stage IV colorectal cancer.

METHODS

We reviewed 100 patients with incurable stage IV colorectal cancer who underwent palliative resection of the primary tumor between 2002 and 2009 at National Cancer Center Hospital East (NCCHE). Outcomes and postoperative course were compared between patients who underwent open and laparoscopic surgery.

RESULTS

Of the 100 patients, 22 were treated with a laparoscopic procedure and 78 underwent an open surgical procedure. There was no difference in the preoperative characteristics of the two groups. In the laparoscopic group, the mean operation time was significantly longer (177 vs. 148 min, p = 0.007) and the amount of blood loss was significantly lower (166 vs. 361 ml, p = 0.002). Postoperative complications occurred in 5 patients (22.7 %) after laparoscopic surgery and in 21 patients (26.9 %) after open surgery, with no significant difference between the two groups. Time to flatus, time to start of food intake, and hospital stay were all shorter after laparoscopic surgery (3.0 vs. 3.8 days, p = 0.003; 3.6 vs. 5.0 days, p < 0.001; and 12.0 vs. 15.0 days, p = 0.005; respectively). Significantly more patients in the laparoscopic group had >15 % lymphocytes on postoperative day 7 (p = 0.049). Overall survival rates were 73.7 and 75.5 % at 1 year after laparoscopic surgery and open surgery, respectively (p = 0.344).

CONCLUSIONS

A laparoscopic procedure should be considered for palliative resection of the primary tumor for incurable stage IV colorectal cancer, because the results of this study indicate that the procedure is safe and effective.

Integration of biologic agents with cytotoxic chemotherapy in metastatic colorectal cancer

Colorectal cancer (CRC) remains a leading cause of cancer death in the developed world. Metastatic disease eventually develops in nearly 50% of patients with CRC. Chemotherapy is the mainstay of treatment in metastatic CRC (mCRC); however the majority of patients remain incurable with current therapeutic options. Progress made in the field of surgery, locoregional treatment for low-volume metastatic disease, and systemic chemotherapy has created new treatment paradigms and improved survival in mCRC. Development of new cytotoxic drugs and the advent of targeted agents over the past decade have seen the median overall survival (OS) for mCRC increase from 9 months to > 2 years. Data from trials integrating targeted therapies appear to indicate that not all have efficacy as single agents and the choice of chemotherapy used in combination with these agents may impact results. Ongoing research is leading to identification of new biomarkers of response, further defining the subpopulations who achieve greatest benefit. Hence optimizing treatment for this group of patients has become increasingly complex, requiring a multidisciplinary approach not only to identify those who are curable with resectable disease but also to determine when it is best to incorporate targeted drugs, with which chemotherapy, and in whom. Currently bevacizumab, cetuximab, and panitumumab are the only approved biologic agents for use in mCRC. In this article we discuss the evidence supporting the use of biologic agents with chemotherapy and suggested strategies for their integration into the treatment armamentarium of mCRC.

Molecular pathways underlying IBD-associated colorectal neoplasia: therapeutic implications

Chronic inflammatory diseases, depending upon the duration and severity, are frequently associated with an increased risk of developing cancer. A classic paradigm is the enhanced risk of colorectal cancer (CRC) in patients with inflammatory bowel disease (IBD). Carcinogenesis is a multifactorial process that involves accumulation of genetic defects, protein modification, and cell-matrix interaction. In this review, we discuss aspects of chronic inflammation in IBD that influence the development of CRC and highlight the key molecular mediators involved in this process. Also, we identify potential targets that could facilitate earlier detection of dysplasia. The targeted manipulation of specific molecules or pathways could provide opportunities for the development of therapeutic and chemopreventive interventions, which may prove effective in arresting the progression of colitis-associated cancer (CAC), with clinical implications.

Impact of KRAS Mutations on Management of Colorectal Carcinoma

The epidermal growth factor receptor (EGFR) pathway is a therapeutic target in the management of colorectal cancer (CRC). EGFR antagonists are active in this disease; however, only a subset of patients respond to such therapy. A Kirsten ras sarcoma viral oncogene (KRAS) wild-type (WT) status of the tumor is necessary, but possibly not sufficient, for a response to anti-EGFR monoclonal antibody therapy. Mechanisms of primary resistance to such therapy in patients harboring KRAS WT tumors are discussed. Strategies to overcome resistance to anti-EGFR monoclonal antibody therapy, including novel agents and combinations of novel therapies, are explored. Also, the use of anti-EGFR monoclonal antibodies in the adjuvant and neoadjuvant setting is reviewed.

Expression of L1CAM, COX-2, EGFR, c-KIT and Her2/neu in anaplastic pancreatic cancer: putative therapeutic targets?

AIMS

Undifferentiated (anaplastic) pancreatic cancer and undifferentiated pancreatic carcinoma with osteoclast-like giant cells (giant cell tumour) are rare variants of pancreatic ductal adenocarcinoma. Representing biologically highly aggressive neoplasms, they are frequently diagnosed at an advanced stage. The response to established chemo- or radiochemotherapeutic treatment regimens is poor, and undifferentiated pancreatic cancer generally has a dismal prognosis. As additional therapeutic options have not yet been investigated in undifferentiated pancreatic cancer, the aim was to analyse the expression of putative therapeutic targets that have shown promising results in various other neoplasms.

METHODS AND RESULTS

Fifteen cases of undifferentiated pancreatic cancer (seven containing osteoclast-like giant cells) were investigated clinicopathologically and immunohistochemically for putative therapeutic targets. Whereas L1CAM, cyclooxygenase (COX)-2 and epidermal growth factor receptor (EGFR) were found to be significantly expressed in 80%, 93% and 87% of the investigated tumours, respectively, there was no substantial expression of c-kit (CD117) and there was no detectable expression of Her2/neu.

CONCLUSIONS

The expression of L1CAM, COX-2 and EGFR in the majority of undifferentiated pancreatic carcinomas suggests that they might represent targets for adjuvant therapy in anaplastic pancreatic cancer. On the other hand, c-kit and Her2/neu seem to have no relevance for the therapy of these tumours.

Phase I trial of oxaliplatin, infusional 5-fluorouracil, and leucovorin (FOLFOX4) with erlotinib and bevacizumab in colorectal cancer

RATIONALE

This phase I study was conducted to determine the maximum tolerated dose (MTD) of erlotinib, an oral epidermal growth factor receptor tyrosine kinase inhibitor, with 5-fluorouracil/leucovorin/oxaliplatin (FOLFOX4) in patients with advanced colorectal cancer (CRC). Bevacizumab was later included as standard of care at the MTD.

PATIENTS AND METHODS

Patients received FOLFOX4 with escalating doses of erlotinib: dose level (DL) 1, 50 mg; DL 2, 100 mg; and DL 3, 150 mg once daily continuously. Bevacizumab 5 mg/kg days 1 and 15 was added at the MTD upon Food and Drug Administration approval. Correlative studies included pharmacokinetics, pharmacodynamics was assessed in paired skin biopsies, and fluorodeoxyglucose positron emission tomography scans.

RESULTS

Fifteen patients received 60 cycles (120 FOLFOX treatments). Two dose-limiting toxicities (DLTs) were seen at DL 3: intolerable grade 2 rash (Common Terminology Criteria for Adverse Events version 2) lasting > 1 week, and grade 4 neutropenia. Dose level 2 was expanded to 6 more patients, this time adding bevacizumab, and 1 DLT of grade 3 mucositis occurred. As expected, the primary toxicities were cytopenias, diarrhea, rash, and fatigue. There were 2 occurrences of pneumatosis. One patient experienced an unrelated grade 4 myocardial infarction before starting chemotherapy. No pharmacokinetic drug interactions were observed. The Response Evaluation Criteria in Solid Tumors response rate was 11 of 14 (78%), median progression-free survival was 9.5 months, and median overall survival was 30 months. Three patients are currently alive > 3 years, with 1 having no evidence of disease.

CONCLUSION

The MTD of erlotinib with FOLFOX4 with or without bevacizumab is 100 mg daily. The regimen appeared to increase toxicity but showed activity in patients with CRC.

Changes in cytokine and biomarker blood levels in patients with colorectal cancer during dendritic cell-based vaccination

INTRODUCTION. Immunotherapy based on dendritic cell vaccination has exciting perspectives for treatment of cancer. In order to clarify immunological mechanisms during vaccination it is essential with intensive monitoring of the responses. This may lead to optimization of treatment and prediction of responding patients. The aim of this study was to evaluate cytokine and biomarker responses in patients with colorectal cancer treated with a cancer vaccine based on dendritic cells pulsed with an allogeneic melanoma cell lysate. MATERIAL AND METHODS. Plasma and serum samples were collected prior to vaccination and continuously during treatment. GM-CSF, IL-2, IL-6, TNF-alpha, IFN-gamma, IL-4, IL-8, IL-1b, IL-5, IL-10, IL-12, MIP-1b, IP-10 and Eotaxin were analyzed in a multiplex assay with a Luminex 100 instrument. CEA and TIMP-1 were analysed on ELISA platforms. RESULTS. Patients achieving stable disease showed increasing levels of plasma GM-CSF, TNF-alpha, IFN-gamma, IL-2, and IL-5. Patients with progressive disease showed significant increase in CEA and TIMP-1 levels, while patients with stable disease showed relatively unaltered levels. CONCLUSION. The increased levels of key pro-inflammatory cytokines in serum of patients who achieved stable disease following vaccination suggest the occurrence of vaccine-induced Th1 responses. Since Th1 responses seem to be essential in cancer immunotherapy this may indicate a therapeutic potential of the vaccine.

Response of the primary tumor in symptomatic and asymptomatic stage IV colorectal cancer to combined interventional endoscopy and palliative chemotherapy

BACKGROUND

The treatment of the primary tumor in advanced metastatic colorectal cancer (CRC) is still a matter of discussion. Little attention has thus far been paid to the endoscopically observable changes of the primary in non-curatively resectable stage IV disease.

METHODS

20 patients [14 men, 6 women, median age 67 (39-82) years] were observed after initial diagnosis of non-curatively resectable metastasized symptomatic (83%) or asymptomatic (17%) CRC, from June 2002 to April 2009. If necessary, endoscopic tumor debulking was performed. 5-FU based chemotherapy was given immediately thereafter. In 10 patients, chemotherapy was combined with antibody therapy.

RESULTS

Response of the primary was observed in all patients. Local symptoms were treated endoscopically whenever necessary (obstruction or bleeding), and further improved after chemotherapy was started: Four patients showed initial complete endoscopic disappearance of the primary. In an additional 6 patients, only adenomatous tissue was histologically detected. In both these groups, two patients revealed local tumor relapse after interruption of therapy. Local tumor regression or stable disease was achieved in the remaining 10 patients. 15 patients died during the observation time. In 13 cases, death was related to metastatic disease progression. The mean overall survival time was 19.6 (3-71) months. No complications due to the primary were observed.

CONCLUSION

This study shows that modern anti-cancer drugs combined with endoscopic therapy are an effective and safe treatment of the symptomatic primary and ameliorate local complaints without the need for surgical intervention in advanced UICC stage IV CRC.

Treatment in advanced colorectal cancer: what, when and how? Br J Cancer. 2009;100:1704-1719. [PMID: 19436303 PMCID: PMC2695695 DOI: 10.1038/sj.bjc.6605061]

Treatment of advanced colorectal cancer (CRC) increasingly requires a multidisciplinary approach and multiple treatment options add to the complexity of clinical decision-making. Recently novel targeted therapy against angiogenesis and epidermal growth factor receptor completed a plethora of phase III studies. The addition of bevacizumab to chemotherapy improved the efficacy over chemotherapy alone in both first and second line settings, although the magnitude of benefit may not be as great when a more optimal chemotherapy platform is used. Studies performed thus far did not address conclusively whether bevacizumab should be continued in subsequent lines of treatment. Anti-angiogenesis tyrosine kinase inhibitors have not shown any additional benefit over chemotherapy alone so far. Although some benefits were seen with cetuximab in all settings of treating advanced CRC, K-ras mutation status provides an important determinant of who would not benefit from such a treatment. Caution should be exercised in combining anti-angiogenesis with anti-EGFR strategy until further randomised data become available. In this review, we have focused on the implications of these trial results on the everyday management decisions of treating advanced CRC.

Local treatment for recurrent colorectal hepatic metastases after partial hepatectomy

OBJECTIVE

The objective of the study was to identify patients who may benefit from local treatment in recurrent colorectal liver metastases.

MATERIALS AND METHODS

A total of 51 consecutive patients were treated for hepatic recurrence(s) after an initial partial hepatic resection. Surgery was considered as the primary treatment option for eligible patients. Patients with a small liver remnant after major hepatectomy were treated with radiofrequency ablation (RFA) or stereotactic body radiation therapy (SRx). SRx was given as an outpatient, emerging local treatment option for patients with intra-hepatic recurrences not eligible for surgery or RFA. Partial liver resection was performed in 36 patients (70%), RFA in ten patients (20%), and SRx in five patients (10%).

RESULTS

Median hospital stay was 7 (range, 3-62) days with a morbidity of 16% without in-hospital death. None of the patients received adjuvant chemotherapy. There was no difference in recurrence or survival between the three treatment modalities. Overall 5-year survival was 35% with an estimated median survival of 37 months. Patients with a disease-free interval between first hepatectomy and hepatic recurrence less than 6 months did not survive 3 years.

CONCLUSIONS

Resection, RFA, and SRx can be performed safely in patients with recurrent colorectal liver metastases and offer a survival that seems comparable to primary liver resections of colorectal liver metastases.

Expression pattern and functional relevance of epidermal growth factor receptor and cyclooxygenase-2: novel chemotherapeutic targets in pancreatic endocrine tumors?

OBJECTIVES

Pancreatic endocrine tumors represent morphologically and biologically heterogeneous neoplasms. Well-differentiated endocrine tumors (benign or of uncertain behavior) can be distinguished from well-differentiated and poorly differentiated endocrine carcinomas. Although many well-differentiated endocrine carcinomas show rather low rates of tumor growth, more than two-thirds of pancreatic endocrine carcinomas display distant metastases at the time of diagnosis. As the currently applied therapies beyond surgery only achieve partial or complete response rates of approximately 15%, additional chemotherapeutic targets are needed, especially in the therapy of inoperable and progressive pancreatic endocrine carcinomas.

METHODS

The expression of epidermal growth factor receptor (EGFR) and cyclooxygenase (COX)-2 were investigated in 110 clinically and pathomorphologically well-characterized pancreatic endocrine tumors, using immunohistochemistry and immunoblot analyses. Functional tests were performed using the human pancreas carcinoid cell line BON and the mouse insulinoma cell line beta-TC-3.

RESULTS

The expression of EGFR correlated significantly with the grade of malignancy, increasing from low rates of expression in benign tumors and tumors of uncertain behavior to high rates of expression in well- and poorly differentiated endocrine carcinomas. The expression of COX-2 was independent of the malignant potential, but was more frequently expressed in primary tumors than in metastases. The treatment of the human pancreas carcinoid cell line BON and the mouse insulinoma cell line beta-TC-3 with EGFR and COX-2 inhibitors (monotherapy and combined therapy) resulted in a significant, dose-dependent reduction of cell viability coupled with increased apoptosis.

CONCLUSIONS

Our results suggest that EGFR and COX-2 may represent useful additional chemotherapeutic targets in pancreatic endocrine tumors.

Clinical relevance of EGFR- and KRAS-status in colorectal cancer patients treated with monoclonal antibodies directed against the EGFR

The epidermal growth factor receptor (EGFR) plays an important role in tumorigenesis and tumor progression of colorectal cancer (CRC). As a result, the EGFR has evolved as a relevant target in the treatment of metastatic CRC. KRAS serves as a mediator between extracellular ligand binding and intracellular transduction of signals from the EGFR to the nucleus. The presence of activating KRAS mutations has been identified as a potent predictor of resistance to EGFR-directed antibodies such as cetuximab or panitumumab. These agents should therefore be applied only in tumors with a wild-type status of the KRAS gene. Further parameters of resistance are lack of EGFR amplification, PTEN loss or BRAF mutation. However, they are less well studied or associated with less consistent data and therefore require prospective analyses before integration into clinical decision making. Future studies need to identify patterns of single or multiple mutations to further increase the power of patient selection for anti-EGFR therapy. While molecular parameters help to predict treatment efficacy upfront, skin toxicity has been accepted as an independent predictor of response during exposure to anti-EGFR therapy.

A phase II study of gefitinib, 5-fluorouracil, leucovorin, and oxaliplatin in previously untreated patients with metastatic colorectal cancer

PURPOSE

We investigated the gefitinib, 5-fluorouracil (5-FU), leucovorin and oxaliplatin (IFOX) regimen as first-line therapy in patients with metastatic colorectal cancer.

EXPERIMENTAL DESIGN

Eligible patients had stage IV colorectal adenocarcinoma, and had not received prior chemotherapy for metastatic disease. Each cycle consisted of 14 days. Cycle 1 consisted of oxaliplatin, leucovorin, and 5-FU (FOLFOX-4). All subsequent cycles consisted of FOLFOX-4 with gefitinib at 500 mg orally daily throughout the 14-day cycle.

RESULTS

Forty-five patients were enrolled and were assessable for toxicity. Forty-three patients were assessable for response. Thirty-one of the 43 patients (72%) had either a complete or partial response by the Response Evaluation Criteria in Solid Tumors. Median overall survival was 20.5 months. Median time to progression was 9.3 months. Commonly encountered grade 3 or 4 toxicities included diarrhea in 67% of patients and neutropenia in 60%. Grade 2 acneiform skin rash typical of gefitinib occurred in 60% of patients.

CONCLUSIONS

IFOX is an active first-line regimen in patients with metastatic colorectal adenocarcinoma, showing higher response rates but also increased toxicities compared with FOLFOX-4 alone in a similar patient population.

Colon cancer: update on adjuvant therapy

Colon cancer is a public health problem worldwide. Although potentially curable at early stages, a substantial number of patients will inevitably present with or eventually develop metastatic disease, which is often incurable. Despite the progress achieved with the introduction of new cytotoxic agents, recurrence rates for patients with resected stage II/III disease remain > 20%. Therefore, a great deal of effort and resources have been put into improving early diagnosis and prevention tools as well as the efficacy of adjuvant treatment. Oxaliplatin-based chemotherapy is now considered the standard of care in node-positive colon cancer, but there remains controversy with regard to the indication and type of adjuvant treatment in patients with nodenegative disease. Oral fluoropyrimidines play a growing role in the management of colorectal cancer and can be currently considered an alternative to 5-fluorouracil. Numerous reports have suggested that elderly patients benefit equally from chemotherapy, but the growing numbers of octogenarian and nonagenarian patients in our clinics, many of whom occasionally struggle through treatment, are a reminder of the challenges ahead. Finally, as we might have reached a plateau in terms of cytotoxic chemotherapy, numerous clinical trials are now focusing on the role of biologic agents in the adjuvant setting.

A phase II randomized multicenter trial of gefitinib plus FOLFIRI and FOLFIRI alone in patients with metastatic colorectal cancer

BACKGROUND

Gefitinib inhibits the epidermal growth factor receptor tyrosine kinase and preclinical studies indicate that it may enhance CPT-11 cytotoxicity. This randomized phase II trial investigates the feasibility and efficacy of gefitinib and 5-fluorouracil, folinic acid, irinotecan (FOLFIRI) in patients with metastatic colorectal cancer.

PATIENTS AND METHODS

Patients were randomized to FOLFIRI +/- gefitinib 250 mg daily p.o. Patients randomized to FOLFIRI + gefitinib without disease progression after 6 months continued to receive gefitinib alone until disease progression.

RESULTS

From October 2002 to September 2004, 100 patients were enrolled. Twenty-three patients (47.9%) in the FOLFIRI arm and 23 (45.1%) in the FOLFIRI + gefitinib arm experienced an objective response. The median progression-free survival and overall survival were 8.3 and 18.6 months in the FOLFIRI arm, and 8.3 and 17.1 months in the FOLFIRI + gefitinib arm, respectively. In the combination arm, grades 3-4 adverse events were experienced by 35 (67.3%) patients versus 25 patients (52.1%) in the FOLFIRI arm; 12 patients (23.1%) withdrew for an adverse event in the FOLFIRI + gefitinib arm and 5 (10.4%) in the FOLFIRI arm.

CONCLUSIONS

These data show that adding gefitinib to FOLFIRI does not improve the efficacy of FOLFIRI regimen. These disappointing results could be related to the high toxicity observed that led to significant dose reductions and delays.

Primary tumour resection and survival in the palliative management of metastatic colorectal cancer

AIM

To examine whether surgical resection of the primary tumour confers a survival benefit and to identify the predictive factors of outcome in patients presenting with asymptomatic metastatic colorectal cancer (CRC).

MATERIALS AND METHODS

A review of a hospital database in a tertiary institution over a 6-year period (1999-2005) revealed 70 patients with asymptomatic primary CRC and unresectable liver metastases treated initially by systemic chemotherapy. A multivariate regression analysis model was used to determine the relative influence of multiple tumours, single/multiple liver metastases, tumour site, differentiation, response of liver and primary tumour to chemotherapy, biochemical response to chemotherapy, age at presentation, performance status and surgical intervention for the CRC primary.

RESULTS

In 67 cases (3 lost to follow-up), 63 had multiple and 4 single surgically irresectable liver metastases. A total of 41 deaths were recorded. All patients received systemic chemotherapy and surgery was performed for bowel obstruction, bleeding or stable disease (n=32). Surgery (OR 0.26; p=0.00013) and clinical response of the primary tumour (OR 0.53; p=0.012) were independently associated with prolonged survival. Proximal tumours (OR 2.61; p=0.0075) and multiple primaries (OR 3.37; p=0.02) were associated with poor outcome.

CONCLUSIONS

Surgical resection and response of the primary tumour to chemotherapy may be associated with improved survival, but proximal or multiple cancers predict poor outcome in patients with asymptomatic CRC and unresectable metastatic disease.

Surgery-predominant combined treatment for colorectal cancer

Colorectal cancer (CRC) is the third most common cancer and the fifth leading cause of cancer-related mortality in China with an increasing trend, which is emphasizing the need for improvements in therapeutic options. The 5-year survival rate of surgery, the first-line treatment for CRC, is just about 50 percent. In recent years many patients with CRC have benefited from the combined treatment with surgery for CRC, which integrates chemotherapy, radiotherapy, concurrent chemoradiotherapy, biotherapy, traditional Chinese medicine, etc., especially patients at advanced stage. This paper highlighted current situation for combined treatment with surgery for CRC.

Epidermal growth factor receptor serum (sEGFR) level may predict response in patients with EGFR-positive advanced colorectal cancer treated with gefitinib?

PURPOSE

Epidermal growth factor receptor-overexpression reported in colorectal cancer, justifies therapeutic use of EGFR-inhibitors. We have recently conducted a phase II study in 57 patients with EGFR-positive advanced colorectal cancer (ACC) who received gefitinib-FOLFOX6 followed by gefitinib-single agent as maintenance. Main biological objective was to assess sEGFR as surrogate marker of tyrosine kinase inhibition and as predictor of response.

METHODS

sEGFR, evaluated by quantitative ELISA, was investigated as predictive factor both taking into account the basal value only, and its whole pattern over time. sEGFR was collected at baseline and at every 2-months assessment in 42 cases. Thirty-three patients reported CR/PR as best objective response (BOR), while nine showed SD/PD.

RESULTS

Retrospectively, on average, the sEGFR values reported by both responders (CR/PR) and not responders (SD/PD) were already different at baseline (49.4 +/- 6.2 and 42.4 +/- 8.4 ng/ml respectively). This difference was statistically significant (p = 0.042). Although sEGFR trend over time confirmed the basal difference (p = 0.032), this result should be taken with caution, due to the small number of patients reporting EGFR values besides the basal one.

CONCLUSIONS

Higher sEGFR at baseline was associated to BOR and may be considered a significant predictor of outcome in patients with ACC.

A phase II study to determine the ability of gefitinib to reverse fluoropyrimidine resistance in metastatic colorectal cancer (the INFORM study)

There are data suggesting that inhibition of epidermal growth factor receptor (EGFR) tyrosine kinase signalling may reverse resistance to fluoropyrimidine treatment. To investigate this further, the INFORM study was an open-label, non-comparative phase II study of gefitinib (Iressa, ZD1839; AstraZeneca, Wilmington, DE, USA) 250 mg daily in combination with 5-fluorouracil (5-FU administered as an intravenous 400 mg m⁻² bolus injection followed by 2800 mg m⁻² infusion over 46 h and folinic acid administered as a 350 mg infusion over 2 h) every 2 weeks for up to 12 cycles in 24 patients with metastatic colorectal cancer refractory to previous fluoropyrimidine treatment. There were no objective responses. The stable disease rate was 37.5% (95% CI: 18.80, 59.41), median progression-free survival measured 116 days and overall survival was 226 days. Quality of life was unchanged compared to baseline values, and the commonest toxicities were diarrhoea, rash and fatigue with 7 out of 24 (29%) patients having a grade 3 or 4 toxicity. Gefitinib does not sensitise patients with fluoropyrimidine refractory metastatic colorectal cancer to 5-FU chemotherapy.

A combination of gefitinib and FOLFOX-4 as first-line treatment in advanced colorectal cancer patients. A GISCAD multicentre phase II study including a biological analysis of EGFR overexpression, amplification and NF-kB activation

Interesting activity has been reported by combining chemotherapy with cetuximab. An alternative approach for blocking EGFR function has been the development of small-molecule inhibitors of tyrosine kinase domain such as gefitinib. We designed a multicentre phase II study in advanced colorectal cancer combining gefitinib+FOLFOX in order to determine the activity and to relate EGFR expression and gene amplification and NF-kB activation to therapeutic results. Patients received FOLFOX-4 regimen plus gefitinib as first-line treatment. Tumour samples were analysed for EGFR protein expression by immunohistochemical analysis and for EGFR gene amplification by fluorescence in situ hybridisation (FISH), chromogenic in situ hybridisation (CISH) and NF-kB activation. Forty-three patients were enrolled into this study; 15 patients experienced a partial response (response rate=34.9%), whereas other 12 (27.9%) had a stable disease. Median progression-free survival (PFS) was 7.8 months and median overall survival (OS) was 13.9 months. We did not find any relationship with EGFR overexpression, gene amplification, while NF-kB activation was associated with a resistance to therapy. Gefitinib does not seem to increase the activity of FOLFOX in advanced colorectal cancer even in patients overexpressing EGFR or with EGFR amplification. Furthermore, while NF-kB activation seems to predict resistance to chemotherapy as demonstrated ‘in vitro’ models, gefitinib does not overcome this mechanism of resistance, as reported for cetuximab.

Targeting the epidermal growth factor receptor in metastatic colorectal cancer. Crit Rev Oncol Hematol. 2008;65:8-20. [PMID: 18006328 DOI: 10.1016/j.critrevonc.2007.09.006]

Although significant advances have been made in the treatment of metastatic colorectal cancer (CRC), prognosis remains poor, with a 5-year survival of less than 10%. Monoclonal antibodies that target the epidermal growth factor receptor (EGFR) have shown clinical benefit as single agents and in combination with standard chemotherapy in the refractory setting, with tolerable toxicity. This article will discuss the role of the EGFR pathway in the pathogenesis of CRC, the data supporting the current use of cetuximab and panitumumab in the treatment of CRC, and clinical trials of EGFR tyrosine kinase inhibitors in CRC. Novel strategies of targeting the EGFR pathway to improve efficacy, as well as ongoing research in identifying molecular predictors of response to anti-EGFR agents, will also be reviewed.