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

Imaging features of gastrointestinal toxicity in non-small cell lung cancer patients treated with erlotinib: A single institute 13-year experience

OBJECTIVES

To investigate the imaging features of erlotinib-associated gastrointestinal toxicity (GT) in patients with non-small cell lung cancer (NSCLC).

MATERIALS AND METHODS

The electronic medical records of 157 patients with NSCLC who received erlotinib between 2005 and 2018 were retrospectively reviewed to identify patients with GT. Clinical and radiologic evidence of erlotinib-associated GT was evaluated. Imaging findings were cross-referenced with clinical presentation, management, and outcomes.

RESULTS

24 (15%) patients (16 women; median age, 68 years) with radiologic evidence of GT were identified. The median time to detection of GT on imaging was 4.5 months (range: 0-58 months). 3/24 (12.5%) patients had no clinical symptoms, but GT was radiologically identified. Erlotinib-associated GT manifested in the large bowel in either a diffuse (42%) or segmental (58%) pattern. The most common imaging finding was fluid-filled bowel (23/24, 96%).

CONCLUSION

Erlotinib-associated GT was identified in 15% patients with NSCLC. Fluid-filled colon and segmental involvement were the most common imaging manifestations.

Bevacizumab and erlotinib versus bevacizumab for colorectal cancer treatment: systematic review and meta-analysis

Background Improving the survival of patients diagnosed with metastatic colorectal cancer requires the use of chemotherapy to be managed with minimum adverse effects. Randomized control trials (RCTs) have shown promising results with a combination of bevacizumab and erlotinib to block two important tumor growth pathways, namely vascular endothelial growth factor and epidermal growth factor receptor. Aim of the Review We aimed to examine the efficacy and safety of the combination of bevacizumab and erlotinib with bevacizumab alone in the maintenance treatment of metastatic colorectal cancer, by examining PFS, OS, overall response rate (ORR), and toxicity. This study performed a systematic review meta-analysis using existing randomized clinical trial. Methods Randomized controlled trials were systematically reviewed from PubMed, Cochrane library, SCOPUS, CRD, and Google scholar databases. After evaluating the quality of studies through the Cochrane checklist, data of the relevant studies were extracted. This meta-analysis included outcomes of overall survival, progression-free survival of the disease through the hazard ratio, and the upper and lower confidence intervals for the third and fourth degree side effects of relative risk. To perform the meta-analysis for both types of survival, two fixed and random effect models were used. Results A total of three trials, providing data of 682 patients who received maintenance treatment, were included in this meta-analysis. Conclusion The combination of bevacizumab and erlotinib significantly increased the overall survival compared to using bevacizumab alone [HR = 0.78, 95% CI 0.66-0.93]. This combination, effectively increased progression-free survival [HR = 0.81, 95% CI 0.7-0.93] too. The side effects of diarrhea and grade III rash were more frequent in the group administered bevacizumab plus erlotinib. The combination of bevacizumab and erlotinib, in the maintenance treatment of metastatic colorectal cancer, significantly improved the overall survival and progression-free survival of patients, and the resulting side effects were easily treatable.

Simultaneous inhibition of IGF1R and EGFR enhances the efficacy of standard treatment for colorectal cancer by the impairment of DNA repair and the induction of cell death

Overexpression and activation of receptor tyrosine kinases (RTKs), such as the insulin-like growth factor 1 receptor (IGF1R) and the epidermal growth factor receptor (EGFR), are frequent phenomena in colorectal cancer (CRC). Here, we evaluated the effect and the cellular mechanisms of the simultaneous inhibition of these two RTKs both in vitro and in vivo in addition to a 5-fluoruracil (5-FU)-based radiochemotherapy (RCT), which is a standard treatment scheme for CRC. Using the small molecule inhibitors AEW541 and erlotinib, specific against IGF1R and EGFR, respectively, different CRC cell lines exhibited a reduced survival fraction after RCT, with the highest effect after the simultaneous inhibition of IGF1R/EGFR. In vivo, xenograft mice simultaneously treated with low dose AEW541/erlotinib plus RCT revealed a significant reduction in tumour volume and weight compared with the tumours of mice treated with either AEW541 or erlotinib alone. In vitro, the combined inhibition of IGF1R/EGFR resulted in a stronger reduction of downstream signalling, an increase in DNA double strand breaks (DSBs), apoptosis and mitotic catastrophe after RCT depending on the cell line. Moreover, the existence of IGF1R/EGFR heterodimers in CRC cells and human rectal cancer samples was proven. The heterodimerisation of these RTKs was dependent on the presence of both ligands, IGF-1 and EGF, and functional receptors. In conclusion, these results demonstrate that the strategy of targeting both IGF1R and EGFR, in addition to basic RCT, could be of intriguing importance in CRC therapy.

Pneumatosis intestinalis after gefitinib therapy for pulmonary adenocarcinoma: a case report

Background

Pneumatosis intestinalis (PI) is defined as the presence of gas in the bowel wall and is a relatively rare finding. PI has been associated with various pathological conditions and medications. Although several chemotherapeutic agents and molecular targeted therapy agents are reported to be associated with PI, there have been few reports describing the association between the anti-epidermal growth factor receptor agent gefitinib, a tyrosine kinase inhibitor (TKI), and PI. The present report describes a case of PI secondary to gefitinib therapy.

Case presentation

An 80-year-old woman who had been diagnosed with recurrent lung adenocarcinoma presented with remarkable appetite loss, abdominal distension, and constipation after starting gefitinib therapy. A computed tomography (CT) scan of the abdomen revealed PI extending from the small intestine to the rectum. The patient was managed conservatively, and gefitinib therapy was discontinued. Subsequently, the symptoms improved and a follow-up abdominal X-ray showed a reduction in intramural air. After gefitinib was restarted, PI occurred three more times.

Conclusions

Although PI is extremely rare, physicians should be aware of the risk of PI in patients undergoing gefitinib therapy.

Maintenance strategy in metastatic colorectal cancer: A systematic review

PURPOSE

Colorectal cancer is the third most common cancer in men and second in women, estimated to cause 694,000 deaths worldwide in 2012. Although 5-year survival rate of CRC has increased, inoperable metastatic colorectal cancer (mCRC) is almost always fatal. The aim of this systematic review is to outline the maintenance strategies that increase the chance and duration of survival with less toxicity and sustained quality of life.

DESIGN

Literature search in PubMed, in American Society of Clinical Oncology (ASCO) Annual Meetings and in ASCO Gastrointestinal Symposia and European Society for Medical Oncology (ESMO) Congresses was performed. Studies conducted in adult patients were written in English language and were published in peer-reviewed journals as phase II or III randomized controlled trials (RCTs) comparing continuous chemotherapy to intermittent chemotherapy, each with or without maintenance therapy was included along with at least one of the outcomes of interest.

RESULTS

Twenty randomized controlled trials and systematic reviews were included from Medline search, together with 4 abstracts from ASCO meetings and 2 abstracts from ESMO meetings.

CONCLUSION

Existing evidence-based data show that prolonged progression free survival (PFS) can be achieved with less toxic regimens compared to complete drug holidays or continued treatment. However, the impact of maintenance on overall survival is less clear. The specific data for maintenance with biological agents are evolving, while in general fluoropyrimidine based maintenance with bevacizumab is better than Bev alone or observation for PFS. Data regarding Cetuximab maintenance are less pronounced than that of Bev maintenance. Preliminary data show that erlotinib-Bev combination may be of benefit as maintenance. Although maintenance may provide significant clinical benefit in clinical studies, the optimal strategy should still be individualized.

Liposomal delivery and polyethylene glycol-liposomal oxaliplatin for the treatment of colorectal cancer (Review)

Oxaliplatin is effective for the treatment of advanced colorectal cancer; however, its application is restricted due to its dose-limiting toxicity. Liposomes are sphere-shaped vesicles consisting of one or more phospholipid bilayers. Liposomes as drug carriers are characterized by delayed release, lesion targeting and may be used as a drug-delivery system to decrease the side effects of cytotoxic drugs. Active targeting modification of liposomes may change the biological distribution of the anticancer agents, reduce or reverse multidrug resistance of tumor cells and enhance the effects of anticancer therapy. Based on the characteristics mentioned above, the aim of the present review was to demonstrate that polyethylene glycol-liposomes containing oxaliplatin may offer advantages for the treatment of colorectal cancer in clinical practice.

Ritonavir and efavirenz significantly alter the metabolism of erlotinib--an observation in primary cultures of human hepatocytes that is relevant to HIV patients with cancer

Erlotinib is approved for the treatment of non-small cell lung and pancreatic cancers, and is metabolized by CYP3A4. Inducers and inhibitors of CYP3A enzymes such as ritonavir and efavirenz, respectively, may be used as part of the highly active antiretroviral therapy drugs to treat patients with human immunodeficiency virus (HIV). When HIV patients with a malignancy need treatment with erlotinib, there is a potential of as-yet-undefined drug-drug interaction. We evaluated these interactions using human hepatocytes benchmarked against the interaction of erlotinib with ketoconazole and rifampin, the archetype cytochrome P450 inhibitor and inducer, respectively. Hepatocytes were treated with vehicle [0.1% dimethylsulfoxide, ritonavir (10 μM)], ketoconazole (10 μM), efavirenz (10 μM), or rifampin (10 μM) for 4 days. On day 5, erlotinib (5 μM) was incubated with the above agents for another 24-48 hours. Concentrations of erlotinib and O-desmethyl erlotinib were quantitated in collected samples (combined lysate and medium) using liquid chromatography and tandem mass spectrometry. The half-life (t(½)) of erlotinib increased from 10.6 ± 2.6 to 153 ± 80 and 23.9 ± 4.8 hours, respectively, upon treatment with ritonavir and ketoconazole. The apparent intrinsic clearance (C(Lint, app)) of erlotinib was lowered 16-fold by ritonavir and 1.9-fold by ketoconazole. Efavirenz and rifampin decreased t1/2 of erlotinib from 10.3 ± 1.1 to 5.0 ± 1.5 and 3.4 ± 0.2 hours, respectively. Efavirenz and rifampin increased the C(Lint, app) of erlotinib by 2.2- and 2-fold, respectively. Our results suggest that to achieve desired drug exposure, the clinically used dose (150 mg daily) of erlotinib may have to be significantly reduced (25 mg every other day) or increased (300 mg daily), respectively, when ritonavir or efavirenz is coadministered.

The status of targeted agents in the setting of neoadjuvant radiation therapy in locally advanced rectal cancers

Radiotherapy has a longstanding and well-defined role in the treatment of resectable rectal cancer to reduce the historically high risk of local recurrence. In more advanced borderline or unresectable cases, where the circumferential resection margin (CRM) is breached or threatened according to magnetic resonance imaging (MRI), despite optimized local multimodality treatment and the gains achieved by modern high quality total mesorectal excision (TME), at least half the patients fail to achieve sufficient downstaging with current schedules. Many do not achieve an R0 resection. In less locally advanced cases, even if local control is achieved, this confers only a small impact on distant metastases and a significant proportion of patients (30-40%) still subsequently develop metastatic disease. In fact, distant metastases have now become the predominant cause of failure in rectal cancer. Therefore, increasing the intensity and efficacy of chemotherapy and chemoradiotherapy by integrating additional cytotoxics and biologically targetted agents seems an appealing strategy to explore-with the aim of enhancing curative resection rates and improving distant control and survival. However, to date, we lack validated biomarkers for these biological agents apart from wild-type KRAS. For cetuximab, the appearance of an acneiform rash is associated with response, but low levels of magnesium appear more controversial. There are no molecular biomarkers for bevacizumab. Although some less invasive clinical markers have been proposed for bevacizumab, such as circulating endothelial cells (CECS), circulating levels of VEGF and the development of overt hypertension, these biomarkers have not been validated and are observed to emerge only after a trial of the agent. We also lack a simple method of ongoing monitoring of 'on target' effects of these biological agents, which could determine and pre-empt the development of resistance, prior to radiological and clinical assessessments or even molecular imaging. These shortcomings probably explain our current relative lack of success in the arena of combining these agents with chemoradiation.

Drug interactions with solid tumour-targeted therapies

Drug interactions are an on-going concern in the treatment of cancer, especially when targeted therapies, such as tyrosine kinase inhibitors (TKI) or mammalian target of rapamycin (mTOR) inhibitors, are being used. The emergence of elderly patients and/or patients with both cancer and other chronic co-morbidities leads to polypharmacy. Therefore, the risk of drug-drug interactions (DDI) becomes a clinically relevant issue, all the more so as TKIs and mTOR inhibitors are essentially metabolised by cytochrome P450 enzymes. These DDIs can result in variability in anticancer drug exposure, thus favouring the selection of resistant cellular clones or the occurrence of toxicity. This review provides a comprehensive overview of DDIs that involve targeted therapies approved by the FDA for the treatment of solid tumours for more than 3 years (sorafenib, sunitinib, erlotinib, gefitinib, imatinib, lapatinib, everolimus, temsirolimus) and medicinal herb or drugs. This review also provides some guidelines to help oncologists and pharmacists in their clinical practice.

Pneumatosis intestinalis and bowel perforation associated with molecular targeted therapy: an emerging problem and the role of radiologists in its management

OBJECTIVE

The purpose of this article is to study the imaging features, management, and outcome of pneumatosis intestinalis and bowel perforation associated with molecular targeted therapy.

MATERIALS AND METHODS

In this retrospective study, 48 patients with cancer who developed pneumatosis or intestinal perforation were found by searching a radiology database. Of these patients, 24 patients (13 women and 11 men; mean age, 61 years; range, 39-83 years) receiving molecular targeted therapy without any confounding factors for pneumatosis or perforation were selected. Initial and follow-up CT scans were evaluated by two radiologists; medical records were reviewed to note clinical features, management, and outcome.

RESULTS

Seventeen (70.8%) patients were asymptomatic. Colorectal cancer (n = 10) and renal cell carcinoma (n = 5) were the most common malignancies; bevacizumab (n = 14) and sunitinib (n = 6) were the most common associated drugs. Imaging findings included intestinal perforation (20 sites in 18 patients), pneumatosis (n = 10), ascites (n = 8), pneumoperitoneum (n = 7), fistula formation (n = 7), and fluid collections (six collections in five patients). Fifteen (62.5%) patients were treated conservatively, seven (29.2%) underwent surgery, and two (8.3%) underwent percutaneous drainage. Molecular targeted therapy was discontinued in 22 of 24 patients; findings resolved in 19 patients, remained stable in one, and worsened in one. One patient died after surgery. In both instances where the drug was continued, the abnormality worsened. Findings recurred in three of four patients in whom the drug was restarted after initial resolution.

CONCLUSION

Radiologists should be aware of intestinal complications associated with molecular targeted therapy, including pneumatosis, bowel perforation, and fistula formation. Most patients can be treated conservatively after discontinuation of molecular targeted therapy. Continuing or restarting molecular targeted therapy can cause worsening or recurrent pneumatosis or perforation.

Investigational therapies targeting the ErbB (EGFR, HER2, HER3, HER4) family in GI cancers

INTRODUCTION

Gastrointestinal (GI) malignancies account for nearly one-fourth of all cancer-related deaths in the United States and approximately 30% of all cancer-related deaths worldwide. Use of combination cytotoxic therapy offers a modest improvement in survival, but the prognosis and long-term survival of most patients with GI cancer remains poor. In certain GI malignancies, therapies that target members of the HER family of receptors have positively impacted patient care.

AREAS COVERED

In this review, we discuss the significance of the HER family of receptors in esophagogastric, hepatobiliary, pancreatic, and colorectal cancers and explain the rationale supporting the use of monoclonal antibodies (mAbs) and small molecule tyrosine kinase inhibitors (TKIs) to inhibit HER activation and downstream events that contribute to tumor proliferation, migration, and survival.

EXPERT OPINION

Despite recent advances, the treatment of GI cancers remains challenging. Therapies targeting the HER family of receptors have been extensively studied in these malignancies with inconsistent results. The rationale behind varied tumor responses with these agents remains uncertain. We believe that additional studies are needed to identify biomarkers that could help identify a population of patients who would be more responsive to a given therapy.

Imaging features of bowel toxicities in the setting of molecular targeted therapies in cancer patients

Molecular targeted therapies are becoming ubiquitous in cancer treatment. These drugs may cause gastrointestinal toxicities including perforation, pneumatosis, enteritis, colitis and fistula formation. Knowledge of these complications and their management enables early radiological identification and appropriate intervention, reducing patient morbidity and mortality.