Regorafenib as a new standard of care in advanced colorectal cancer

SUMMARY 

Standard treatment for metastatic colorectal cancer (mCRC) involves chemotherapy based on fluoropyrimidines, oxaliplatin, irinotecan and treatments targeting the angiogenic pathway, and EGFR in RAS wild-type tumors. Regorafenib, an active multikinase inhibitor, demonstrated activity against mCRC in Phase I and II studies. The CORRECT study demonstrated activity of regorafenib in third line versus placebo. The primary end point (overall survival), was met (6.4 vs 5.0 months [hazard ratio: 0.77; 95% CI: 0.64–0.94; p = 0.0052]). Median progression-free survival was 1.9 versus 1.7 months (hazard ratio: 0.49; 95% CI: 0.42–0.58; p < 0.0001). Most common adverse events of regorafenib were hand–foot skin reaction, fatigue, diarrhea, hypertension and rash or desquamation and stomatitis, but with a close management and/or dose modifications were controlled. In conclusion, regorafenib is a new standard in third line in mCRC.

Regorafenib: a review of its use in previously treated patients with progressive metastatic colorectal cancer

Regorafenib (Stivarga) is an inhibitor of multiple protein kinases, including those involved in oncogenesis, tumour angiogenesis and maintenance of the tumour microenvironment. The drug is approved as monotherapy for the treatment of metastatic colorectal cancer (mCRC) in patients who have previously received all standard systemic anticancer treatments (US, EU and Canada) or in patients with unresectable, advanced or recurrent colorectal cancer (Japan). In the randomized, controlled COloRectal cancer treated with REgorafenib or plaCebo after failure of standard Therapy (CORRECT) trial, regorafenib 160 mg once daily for the first 3 weeks of each 4-week cycle plus best supportive care (BSC) was associated with a significantly longer median overall survival than placebo plus BSC in patients with previously treated, progressive mCRC. The drug was also associated with significantly longer progression-free survival and better disease control rates than placebo, although objective response rates were similar in both treatment groups. Regorafenib did not appear to compromise health-related quality of life over the study duration and had a generally acceptable tolerability profile. The introduction of regorafenib expands the currently limited range of effective treatment options in patients with previously treated, progressive mCRC.

Potent antitumor activity of cabozantinib, a c-MET and VEGFR2 inhibitor, in a colorectal cancer patient-derived tumor explant model

Antiangiogenic therapy is commonly used for the treatment of colorectal cancer (CRC). Although patients derive some clinical benefit, treatment resistance inevitably occurs. The MET signaling pathway has been proposed to be a major contributor of resistance to antiangiogenic therapy. MET is upregulated in response to vascular endothelial growth factor pathway inhibition and plays an essential role in tumorigenesis and progression of tumors. In this study, we set out to determine the efficacy of cabozantinib in a preclinical CRC patient-derived tumor xenograft model. We demonstrate potent inhibitory effects on tumor growth in 80% of tumors treated. The greatest antitumor effects were observed in tumors that possess a mutation in the PIK3CA gene. The underlying antitumor mechanisms of cabozantinib consisted of inhibition of angiogenesis and Akt activation and significantly decreased expression of genes involved in the PI3K pathway. These findings support further evaluation of cabozantinib in patients with CRC. PIK3CA mutation as a predictive biomarker of sensitivity is intriguing and warrants further elucidation. A clinical trial of cabozantinib in refractory metastatic CRC is being activated.

DNA synthesis inhibitors for the treatment of gastrointestinal cancer

INTRODUCTION

Intensive laboratory, preclinical and clinical studies have identified and validated molecular targets in cancers, leading to a shift toward the development of novel, rationally designed and specific therapeutic agents. However, gastrointestinal cancers continue to have a poor prognosis, largely due to drug resistance.

AREAS COVERED

Here, we discuss the current understanding of DNA synthesis inhibitors and their mechanisms of action for the treatment of gastrointestinal malignancies.

EXPERT OPINION

Conventional agents, including DNA synthesis inhibitors such as fluoropyrimidines and platinum analogs, remain the most effective therapeutics and are the standards against which new drugs are compared. Novel DNA synthesis inhibitors for the treatment of gastrointestinal malignancies include a combination of the antimetabolite TAS-102, which consists of trifluorothymidine with a thymidine phosphorylase inhibitor, and a novel micellar formulation of cisplatin NC-6004 that uses a nanotechnology-based drug delivery system. The challenges of translational cancer research using DNA synthesis inhibitors include the identification of drugs that are specific to tumor cells to reduce toxicity and increase antitumor efficacy, biomarkers to predict pharmacological responses to chemotherapeutic drugs, identification of ways to overcome drug resistance and development of novel combination therapies with DNA synthesis inhibitors and other cancer therapies, such as targeted molecular therapeutics. Here, we discuss the current understanding of DNA synthesis inhibitors and their mechanisms of action for the treatment of gastrointestinal malignancies.

Aflibercept--a decoy VEGF receptor

Aflibercept (known as ziv-aflibercept in the USA and sold under the trade name Zaltrap®) is a human recombinant fusion protein with antiangiogenic effects that functions as a decoy receptor to bind vascular endothelial growth factors A and B and placental growth factor. Its unique mechanism of action with respect to other agents targeting angiogenesis led investigators to speculate that it may be more ubiquitously efficacious in tumors highly dependent on pathologic angiogenesis for their growth. Despite encouraging preclinical studies in various tumor types, aflibercept has not been proven efficacious in most later-phase clinical studies. In fact, its only currently held US Food and Drug Administration indication is in metastatic colorectal cancer in combination with 5-fluorouracil, leucovorin, and irinotecan for those patients previously treated with an oxaliplatin-containing chemotherapy regimen. Given aflibercept's toxicity profile and cost, further investigation is needed to better understand its mechanism of action and to discover predictive biomarkers for optimization of its appropriate use in treatment of cancer patients.

Endoglin for targeted cancer treatment

Endoglin is a homodimeric cell membrane glycoprotein receptor for transforming growth factor β and bone morphogenetic proteins. Endoglin is essential for angiogenesis, being densely expressed on proliferating endothelial cells and upregulated during hypoxia. Its expression is implicated in development of resistance to vascular endothelial growth factor (VEGF) inhibition. TRC105 is an antibody that binds endoglin and prevents endothelial cell activation. Targeting endoglin and the VEGF pathway concurrently improves treatment in vitro and appears to reverse resistance to bevacizumab in some refractory cancer patients. Randomized trials are under way to assess the clinical benefit of adding TRC105 therapy to bevacizumab therapy. Further trials are under way to assess the activity of TRC105 with small-molecule inhibitors of the VEGF pathway in renal cell carcinoma, hepatocellular carcinoma, and soft tissue sarcoma. Stratification of soft tissue sarcomas based on endoglin expression levels is proposed to identify patients most likely to benefit from TRC105 treatment. The development of a TRC105 antibody-drug conjugate is also described.

Dissecting signaling pathways in hepatocellular carcinoma: new perspectives in medical therapy

Prognosis of patients with advanced hepatocellular carcinoma (HCC) is poor and is largely influenced by associated liver comorbidities. Moreover, effective treatment alternatives are limited; with the exception of the multitargeted inhibitor sorafenib, established options in the treatment of advanced HCC no longer amenable with ablative or locoregional procedures are lacking. In light of the limited efficacy of chemotherapy in this setting, great efforts have been made in the definition of targetable molecular pathways with a central role in the progression of HCC. Targeting angiogenesis, growth factor receptors, intracellular transduction pathways, or mechanisms of gene-expression regulation represents the main way to improve patient outcome. At the same time, identifying clinical and biological factors, which may help selecting patients with higher chances of benefit, is essential in order to hasten drug development and maximize treatment efficacy.

Cost-effectiveness of aspirin adjuvant therapy in early stage colorectal cancer in older patients

BACKGROUND & AIMS

Recent observational studies showed that post-operative aspirin use reduces cancer relapse and death in the earliest stages of colorectal cancer. We sought to evaluate the cost-effectiveness of aspirin as an adjuvant therapy in Stage I and II colorectal cancer patients aged 65 years and older.

METHODS

Two five-state Markov models were constructed separately for Stage I and II colorectal cancer using TreeAge Pro 2014. Two hypothetical cohorts of 10,000 individuals at a starting age of 65 years and with colorectal cancer in remission were put through the models separately. Cost-effectiveness of aspirin was evaluated against no treatment (Stage I and II) and capecitabine (Stage II) over a 20-year period from the United States societal perspective. Extensive one-way sensitivity analyses and multivariable Probabilistic Sensitivity Analyses (PSA) were performed.

RESULTS

In the base case analyses, aspirin was cheaper and more effective compared to other comparators in both stages. Sensitivity analyses showed that no treatment and capecitabine (Stage II only) can be cost-effective alternatives if the utility of taking aspirin is below 0.909, aspirin's annual fatal adverse event probability exceeds 0.57%, aspirin's relative risk of disease progression is 0.997 or more, or when capecitabine's relative risk of disease progression is less than 0.228. Probabilistic Sensitivity Analyses (PSA) further showed that aspirin could be cost-effective 50% to 80% of the time when the willingness-to-pay threshold was varied from USD 20,000 to USD 100,000.

CONCLUSION

Even with a modest treatment benefit, aspirin is likely to be cost-effective in Stage I and II colorectal cancer, thus suggesting a potential unique role in secondary prevention in this group of patients.

Colorectal cancer with liver metastases: Neoadjuvant chemotherapy, surgical resection first or palliation alone?

Colorectal cancer (CRC) is one of the commonest cancers with 1.2 million new cases diagnosed each year in the world. It remains the fourth most common cause of cancer-related mortality in the world and accounts for > 600000 cancer-related deaths each year. There have been significant advances in treatment of metastatic CRC in last decade or so, due to availability of new active targeted agents and more aggressive approach towards the management of CRC, particularly with liver-only-metastases; however, these drugs work best when combined with conventional chemotherapy agents. Despite these advances, there is a lack of biomarkers to inform us about the accurate management of the patients with metastatic CRC. It is therefore imperative to carefully select the patients with comprehensive multi-disciplinary team input in order to optimise the management of these patients. In this review we will discuss various treatment options available in management of colorectal liver metastases with potential guidance on how and when to choose these options along with consideration on future directions in management of this disease.

Raising the bar for antineoplastic agents: how to choose threshold values for superiority trials in advanced solid tumors

PURPOSE

To establish the concept of minimum clinically meaningful outcome (mCMO) of treatment in advanced solid tumors, to establish its threshold and evaluate how many superiority trials of new antineoplastic agents pass this threshold.

EXPERIMENTAL DESIGN

We chose overall survival as the primary indicator of patient benefit. Four conceptually different types of treatment effect can be identified in OS curves: HR, gains in median OS, proportional, and absolute increases at long-term OS. We postulated threshold levels for these four parameters defining the mCMO and set the bar at three different levels of required benefit: high, medium, and low. The postulated values were then studied by comparing our thresholds with the actual results of the pivotal superiority phase III trials on new drugs reporting on mature OS data.

RESULTS

Forty-three trials on 35,419 patients in 12 cancer types on 23 novel agents met these criteria. Only two trials reached the postulated "high" thresholds for HR and median OS. The number of "positive trials" increased to eight and 15 when the bar was lowered to the "medium" and "low" levels, respectively. The same analysis was done for proportional and absolute increases in long-term OS. No trial satisfied the criteria for long-term benefit, whereas only two and nine trials satisfied both parameters for the "medium and low" required benefit levels, respectively.

CONCLUSIONS

All four OS-related parameters contribute to define the mCMO. If the bar for the mCMO is raised too much, positive trials are exceptional.

Biological and molecular effects of small molecule kinase inhibitors on low-passage human colorectal cancer cell lines

Low-passage cancer cell lines are versatile tools to study tumor cell biology. Here, we have employed four such cell lines, established from primary tumors of colorectal cancer (CRC) patients, to evaluate effects of the small molecule kinase inhibitors (SMI) vemurafenib, trametinib, perifosine, and regorafenib in an in vitro setting. The mutant BRAF (V600E/V600K) inhibitor vemurafenib, but also the MEK1/2 inhibitor trametinib efficiently inhibited DNA synthesis, signaling through ERK1/2 and expression of genes downstream of ERK1/2 in BRAF mutant cells only. In case of the AKT inhibitor perifosine, three cell lines showed a high or intermediate responsiveness to the drug while one cell line was resistant. The multikinase inhibitor regorafenib inhibited proliferation of all CRC lines with similar efficiency and independent of the presence or absence of KRAS, BRAF, PIK3CA, and TP53 mutations. Regorafenib action was associated with broad-range inhibitory effects at the level of gene expression but not with a general inhibition of AKT or MEK/ERK signaling. In vemurafenib-sensitive cells, the antiproliferative effect of vemurafenib was enhanced by the other SMI. Together, our results provide insights into the determinants of SMI efficiencies in CRC cells and encourage the further use of low-passage CRC cell lines as preclinical models.

Medical treatment of advanced thoracic neuroendocrine tumors

Thoracic Neuroendocrine Tumors (TNETs) range from the more indolent behavior of the well-differentiated to the highly aggressive poorly differentiated forms. A clinical approach totally different in terms of diagnosis and treatment is therefore required. Chemotherapy and radiotherapy are the treatments of choice in poorly differentiated, whereas biological and target therapy, peptide receptor radionuclide therapy (PPRT) and temozolomide have shown efficacy in small series or in the subgroup analysis of larger trials in well differentiated. However, no specific trials have been performed before this year. The first large, prospective, randomized trial (LUNA trial) entirely dedicated to TNET is ongoing at the time of this publication.

Joint detection of ERCC1, TUBB3, and TYMS guidance selection of docetaxel, 5-fluorouracil and cisplatin (DDP) individual chemotherapy in advanced gastric cancer patients

Background

To investigate the guidance selection of docetaxel (D), cisplatin (DDP) (C), and 5-fluorouracil (5-FU) (F) as individual chemotherapy agents via joint detection of ERCC1, TUBB3, and TYMS genes in patients with advanced gastric cancer (AGC).

Method

Clinical data of 120 patients with AGC who enrolled in our hospital between May 2009 and May 2012 were analyzed. These patients were randomly assigned to experimental and control groups. The mRNA expression of ERCC1, TUBB3, and TYMS was measured by DNA chip technology in the experimental group. Different chemotherapies were administered according to the mRNA expression levels of the three genes, while DCF chemotherapy was directly applied to the control group. Correlation between the three genes’ mRNA levels, efficiency rate, the median time to progression (MTP), median survival time (MST) and adverse reactions was evaluated.

Results

As a result, there was a significant correlation between ERCC1 and TUBB3 mRNA expression (P = 0.005), but no obvious correlation between TUBB3 and TYMS or ERCC1 and TYMS. There was also no significant difference in the efficiency rate of chemotherapy (50% versus 55%; P = 0.357) and the MTP (10 months versus 7 months; P = 0.091) between the two groups. However, there was obvious significance in MST (13.7 months versus 11.6 months; P = 0.004). Additionally, the experimental group provided us with a more effective way for controlling adverse reactions to chemotherapy.

Conclusion

Combination regimen of D, C, and F in AGC patients according to their ERCC1, TUBB3, and TYMS mRNA expression level may reduce adverse reactions and improve MST.

Ectopic Cushing and other paraneoplastic syndromes in thoracic neuroendocrine tumors

Overproduction of corticotropin by the pituitary gland or extrapituitary tumors leads to hypercortisolism or Cushing syndrome. Diagnosis of suspected Cushing syndrome involves 3 major steps: confirmation of hypercortisolism, differentiation between corticotropin-independent and corticotropin-dependent causes of Cushing syndrome, and distinction between pituitary and ectopic corticotropin production. A definitive diagnosis of ectopic corticotropin secretion requires stringent criteria, including reversal of the clinical picture after resection of the tumor and/or demonstration of corticotropin immunohistochemical staining within the tumor tissue.

Monitoring early response to anti-angiogenic therapy: diffusion-weighted magnetic resonance imaging and volume measurements in colon carcinoma xenografts

OBJECTIVES

To evaluate the use of diffusion-weighted MRI (DW-MRI) and volume measurements for early monitoring of antiangiogenic therapy in an experimental tumor model.

MATERIALS AND METHODS

23 athymic nude rats, bearing human colon carcinoma xenografts (HT-29) were examined before and after 6 days of treatment with regorafenib (n = 12) or placebo (n = 11) in a clinical 3-Tesla MRI. For DW-MRI, a single-shot EPI sequence with 9 b-values (10-800 s/mm2) was used. The apparent diffusion coefficient (ADC) was calculated voxelwise and its median value over a region of interest, covering the entire tumor, was defined as the tumor ADC. Tumor volume was determined using T2-weighted images. ADC and volume changes between first and second measurement were evaluated as classifiers by a receiver-operator-characteristic (ROC) analysis individually and combined using Fisher's linear discriminant analysis (FLDA).

RESULTS

All ADCs and volumes are stated as median±standard deviation. Tumor ADC increased significantly in the therapy group (0.76±0.09×10(-3) mm2/s to 0.90±0.12×10(-3) mm2/s; p<0.001), with significantly higher changes of tumor ADC than in the control group (0.10±0.11×10(-3) mm2/s vs. 0.03±0.09×10(-3) mm2/s; p = 0.027). Tumor volume increased significantly in both groups (therapy: 347.8±449.1 to 405.3±823.6 mm3; p = 0.034; control: 219.7±79.5 to 443.7±141.5 mm3; p<0.001), however, the therapy group showed significantly reduced tumor growth (33.30±47.30% vs. 96.43±31.66%; p<0.001). Area under the curve and accuracy of the ADC-based ROC analysis were 0.773 and 78.3%; and for the volume change 0.886 and 82.6%. The FLDA approach yielded an AUC of 0.985 and an accuracy of 95.7%.

CONCLUSIONS

Regorafenib therapy significantly increased tumor ADC after 6 days of treatment and also significantly reduced tumor growth. However, ROC analyses using each parameter individually revealed a lack of accuracy in discriminating between therapy and control group. The combination of both parameters using FLDA substantially improved diagnostic accuracy, thus highlighting the potential of multi-parameter MRI as an imaging biomarker for non-invasive early tumor therapy monitoring.

Malignant priapism secondary to isolated penile metastasis from a renal pelvic carcinoma

We report a case of isolated penile metastasis from renal pelvic carcinoma in a 69-year-old man with malignant priapism. The patient had radical resection of the renal pelvic carcinoma 2 months earlier with urothelial carcinoma (UC) and sarcomatoid differentiation histology. Physical examination showed no visible skin lesions, but a palpable hard nodule was present over the penile shaft. The imaging studies did not reveal other metastases. Cavernous-Glans shunt and nodule resection were performed, and histological examination showed metastasis UC with sarcomatoid differentiation. To our knowledge, we describe the first case of malignant priapism due to isolated penile metastasis of renal pelvic carcinoma.

Regorafenib as a single-agent in the treatment of patients with gastrointestinal tumors: an overview for pharmacists

Regorafenib (BAY 73-4506, Stivarga® Bayer HealthCare Pharmaceutical Inc) is an oral multikinase inhibitor with a distinct and wide-ranging profile of tyrosine kinase inhibition, resulting in antiangiogenic and antiproliferative properties in tumors. Single-agent regorafenib administered as a 160-mg daily dose for the first 21 days of a 28-day cycle is approved for use in patients with pretreated metastatic colorectal cancer (mCRC) and gastrointestinal stromal tumor (GIST) progressing on imatinib and sunitinib, following publication of data from the phase III CORRECT and GRID studies respectively. Regorafenib is currently under phase III investigation in patients with hepatocellular carcinoma and is in several phase II studies in patients with gastrointestinal (GI) tumors. This review describes the clinical development of regorafenib in patients with GI cancers, and highlights the key issues important for the modern day clinical pharmacist who forms part of the multidisciplinary team ensuring safe and effective delivery of the drug to the patient. This information is considered of particular importance to the clinical pharmacist for the future development of regorafenib in this treatment setting.

The role of biological therapy in metastatic colorectal cancer after first-line treatment: a meta-analysis of randomised trials

PURPOSE

Biologic agents have achieved variable results in relapsed metastatic colorectal cancer (mCRC). Systematic meta-analysis was undertaken to determine the efficacy of biological therapy.

METHODS

Major databases were searched for randomised studies of mCRC after first-line treatment comparing (1) standard treatment plus biologic agent with standard treatment or (2) standard treatment with biologic agent with the same treatment with different biologic agent(s). Data were extracted on study design, participants, interventions and outcomes. Study quality was assessed using the MERGE criteria. Comparable data were pooled for meta-analysis.

RESULTS

Twenty eligible studies with 8225 patients were identified. The use of any biologic therapy improved overall survival with hazard ratio (HR) 0.87 (95% confidence interval (CI) 0.82-0.91, P<0.00001), progression-free survival (PFS) with HR 0.71 (95% CI 0.67-0.74, P<0.0001) and overall response rate (ORR) with odds ratio (OR) 2.38 (95% CI 2.03-2.78, P<0.00001). Grade 3/4 toxicity was increased with OR 2.34. Considering by subgroups, EGFR inhibitors (EGFR-I) in the second-line setting and anti-angiogenic therapies (both in second-line and third-line and beyond settings) all improved overall survival, PFS and ORR. EGFR-I in third-line settings improved PFS and ORR but not OS.

CONCLUSIONS

The use of biologic agents in mCRC after first-line treatment is associated with improved outcomes but increased toxicity.

SEOM clinical guidelines for the diagnosis and treatment of gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) 2014

GEP-NENs are a challenging family of tumors of growing incidence and varied clinical management and behavior. Diagnostic techniques have substantially improved over the past decades and significant advances have been achieved in the understanding of the molecular pathways governing tumor initiation and progression. This has already translated into relevant advances in the clinic. This guideline aims to provide practical recommendations for the diagnosis and treatment of GEP-NENs. Diagnostic workup, histological and staging classifications, and the different available therapeutic approaches, including surgery, liver-directed ablative therapies, peptide receptor radionuclide therapy, and systemic hormonal, cytotoxic or targeted therapy, are briefly discussed in this manuscript. Clinical presentation (performance status, comorbidities, tumor-derived symptoms and hormone syndrome in functioning tumors), histological features [tumor differentiation, proliferation rate (Ki-67), and expression of somatostatin receptors], disease localization and extent, and resectability of primary and metastatic disease, are all key issues that shall be taken into consideration to appropriately tailor therapeutic strategies and surveillance of these patients.

Clinical experience with ramucirumab : outcomes in breast cancer

INTRODUCTION

Monoclonal antibodies and small molecules targeting the VEGF pathway are part of the arsenal to treat malignant tumors. Antiangiogenesis therapies has been studied in breast cancer with partial success, reflected by the approval of bevacizumab in Europe but not in United States, for metastatic breast cancer (mBC). Ramucirumab is a mAb against VEGFR-2 interfering with the normal activation of this receptor by its natural ligand VEGF.

AREAS COVERED

This article will review the preclinical data available to date for ramucirumab, as well as survey the main clinical trials of antiangiogenic agents reported in breast cancer, focusing on Phase III clinical trials. It will also review the clinical trial data for ramucirumab in mBC, including the design of the Phase II trials, and report on the preliminary results of the TRIO-012 trial. This trial did not meet its primary end point in progression-free survival and has to be considered as a negative trial.

EXPERT OPINION

Despite preliminary positive data with ramucirumab in other metastatic solid tumors reported to date, the results of TRIO-012 discourage pursuing more efforts with ramucirumab in mBC unless predictive and reproducible biomarkers can be established to select those patients who are most likely to benefit from it.

Phase II trial of gemcitabine plus UFT as salvage treatment in oxaliplatin, irinotecan and fluoropyrimidine-refractory metastatic colorectal cancer

PURPOSE

To investigate the efficacy of gemcitabine plus uracil-tegafur (UFT) combination chemotherapy as a salvage treatment in patients with metastatic colorectal cancer (MCRC).

METHODS

This single-arm phase II study was conducted at three institutions in Korea. Patients with MCRC refractory to fluoropyrimidine, oxaliplatin and irinotecan were enrolled. Gemcitabine 800 mg/m(2) was administered intravenously on days 1, 8 and 15. UFT 200 mg/m(2)/day was taken orally in three divided doses on days 1-21. Cycles were repeated every 4 weeks, and tumor evaluation was carried out every 8 weeks. The primary endpoint of this study was 8-week progression-free survival (PFS) rate.

RESULTS

Forty-one patients were enrolled. Fourteen patients received gemcitabine/UFT as a third-line treatment and 37 patients as a fourth-line or later-line therapy. Toxicities were easily manageable, and non-hematologic toxicities of ≥grade 3 were rare. The most common toxicity of ≥grade 3 was neutropenia (20.0 %). One patient showed partial response (response rate, 2.4 %) and 14 (34.1 %) showed stable disease. The 8-week PFS rate was 42.3 %. The median PFS was 1.7 months [95 % confidence interval (CI) 1.6-1.8 months], and the median overall survival was 9.2 months (95 % CI 5.8-12.6 months).

CONCLUSIONS

Overall efficacy of gemcitabine/UFT in refractory MCRC was unsatisfactory. However, we could find a minor proportion of patients who showed prolonged tumor stabilization to gemcitabine/UFT. Further studies are warranted to identify a patient subgroup that might have benefits from gemcitabine/UFT therapy.

Advances in the management of colorectal cancer: from biology to treatment

BACKGROUND

Colorectal cancer (CRC) is the third most common malignant neoplasm worldwide and the fourth leading cause of cancer-related deaths. This article reviews the epidemiology, risk factors, pathogenesis, and prognosis of CRC with special emphasis on advances in the management of CRC over the past decade.

METHODS

A review of the published English literature was conducted using the search engines PubMed, Medline, EMBASE, and Google Scholar. A total of 127 relevant publications were identified for further review.

RESULTS

Most CRC are sporadic and are due to genetic instability and multiple somatic mutations. Approximately 80% of cancers are diagnosed at the early stage and are curable. The pathologic stage at presentation is the most important predictor of outcome after resection of early stage cancer. Surgery is the primary treatment modality for localized CRC. Advances in (neo)adjuvant chemotherapy and radiation have reduced the disease recurrence and increased survival in high risk diseases. Although recent advancements in combination chemotherapy and target agents have increased the survival of incurable CRC, it is remarkable that only selected patients with advanced CRC can be cured with multimodality therapy.

CONCLUSION

Over the past decade, there has seen substantial progress in our understanding of and in the management of CRC.

Risk of mucocutaneous toxicities in patients with solid tumors treated with everolimus; a systematic review and meta-analysis

BACKGROUND

We performed a systematic review and meta-analysis of mucocutaneous toxicities associated with the use of everolimus in solid tumors.

PATIENTS AND METHODS

Eligible studies included randomized Phase II and III trials of patients with solid tumors on everolimus; describing events of stomatitis, skin rash, pruritus and mouth ulceration.

RESULTS

Our search strategy yielded 380 potentially relevant citations on everolimus from Pubmed/Medline, CENTRAL Cochrane registry and American Society of Clinical Oncology meeting library. After exclusion of ineligible studies, a total of 10 clinical trials were considered eligible for the meta-analysis, including eight Phase III trials and two Phase II trials. The relative risk of all-grade stomatitis, skin rash, pruritus and mouth ulceration were 3.86(95% CI: 2.23-6.68; p < 0.001); 3.49(95% CI: 2.39-5.08; p < 0.0001); 2.85(95% CI: 2.04-3.97; p = 0.0001); 3.31 (95% CI: 1.46-7.50; p = 0.004); respectively. Exploratory subgroup analysis showed no effect of tumor types or treatment regimen on the relative risk of the relevant adverse events.

CONCLUSION

Our meta-analysis has demonstrated that everolimus is associated with a significantly increased risk of all-grade stomatitis, skin rash, and pruritus and mouth ulceration. Clinicians should be aware of these risks and perform early clinical assessment and intervene accordingly.

Chemotherapy for locally advanced and metastatic pulmonary carcinoid tumors

OBJECTIVES

The optimal management of locally advanced and metastatic pulmonary carcinoid tumors remains to be determined.

MATERIALS AND METHODS

A retrospective review was conducted on patients with typical and atypical pulmonary carcinoid tumors treated at our institutions between 1990 and 2012.

RESULTS

300 patients were identified with pulmonary carcinoid, (80 patients with atypical carcinoid), of whom 29 presented with metastatic disease (16 atypical). Of evaluable patients, 26 (41%) with stages I-III atypical carcinoid tumors recurred at a median time of 3.7 years (range, 0.4-32), compared to 3 (1%) patients with typical carcinoid (range, 8-12.3). 39 patients were treated with chemotherapy, including 30 patients with metastatic disease (27 atypical), and 7 patients were treated with adjuvant platinum-etoposide chemoradiation (6 atypical, 1 typical, 6 stage IIIA, 1 stage IIB). At a median follow-up of 2 years there were 2 recurrences in the 7 patients receiving adjuvant treatment. Median survival after diagnosis of metastatic disease for patients with atypical pulmonary carcinoid was 3.3 years with a 5-year survival of 24%. Treatment regimens showing efficacy in pulmonary carcinoid include 15 patients treated with octreotide-based therapies (10% response rate (RR), 70% disease control rate (DCR), 15 month median progression-free survival (PFS)), 13 patients treated with etoposide+platinum (23% RR, 69% DCR, 7 month median PFS), and 14 patients treated with temozolomide-based therapies (14% RR, 57% DCR, 10 month median PFS). 8 of 10 patients with octreotide-avid disease treated with an octreotide-based regimen experienced disease control (1 partial response, 7 stable disease) for a median of 18 months (range 6-72 months).

CONCLUSIONS

These results support our previous finding that a subset of pulmonary carcinoid tumors are responsive to chemotherapy.

An open-label study to determine the maximum tolerated dose of the multitargeted tyrosine kinase inhibitor CEP-11981 in patients with advanced cancer

Background This phase I study evaluated the pharmacokinetics and pharmacodynamics of CEP-11981, an oral vascular endothelial growth factor (VEGF) tyrosine kinase inhibitor, in patients with advanced, relapsed, or refractory solid tumors. Methods Oral CEP-11981 dose escalations followed a modified Fibonacci sequence (from 3.0 to 4.2, 5.9, 11.8, 19.7, 29.6, 41.4, 55.0, 73.0, 97.4, and 126.6 mg/m²). The maximum-tolerated dose (MTD), dose-limiting toxicities (DLTs), tumor response, and safety were evaluated. Results CEP-11981 was tolerated at doses between 3.0 and 97.4 mg/m². The MTD of CEP-11981 was determined to be 97.4 mg/m², with DLTs observed at the 126.6 mg/m² dose. The DLTs were grade 4 neutropenia in 1 patient and grade 3 T-wave inversion with chest heaviness and fatigue in 1 patient. All 3 events resolved on stopping CEP-11981. The most frequently reported adverse events of any grade were fatigue, nausea, diarrhea, decreased appetite, abdominal pain, back pain, vomiting, constipation, headache, dizziness, and dyspnea. Treatment-related grade 3/4 neutropenia was observed in the highest-dose cohorts (2 patients at 97.4 mg/m² and 1 patient at 126.6 mg/m²), indicating some off-target inhibition. VEGF inhibition was greatest in the higher-dose groups. Although no patient experienced complete or partial response, 44 % patients achieved stable disease when measured at ≥ 6 weeks, which occurred more frequently in cohorts receiving ≥ 73.0 mg/m². Conclusions In patients with recurrent or refractory solid tumors, disease stabilization was achieved. Despite acceptable tolerability of CEP-11981 at the MTD, further development by the sponsor has ceased.

Current opinion on optimal systemic treatment for metastatic colorectal cancer: outcome of the ACTG/AGITG expert meeting ECCO 2013

The treatment of metastatic colorectal cancer has evolved greatly in the last 15 years, involving combined chemotherapy protocols and, in more recent times, new biologic agents. Clinical benefit from the use of targeted therapy with bevacizumab, aflibercept, cetuximab, panitumumab and regorafenib in the treatment of metastatic colorectal cancer is now well established with median overall survival accepted as over 24 months, and with super selection for extended RAS patients higher again. The optimal timing of treatment options requires careful consideration of predictive biomarkers, and importantly the potential for interactions, to derive the maximal benefit. A group of colorectal subspecialty medical oncologists from Australia, the USA, the Netherlands and Germany met during ECCO 2013 to discuss current practice. Subsequent new data from the American Society of Clinical Oncology were also reviewed. This article reviews the evidence discussed in support of modern treatments for colorectal cancer and the decision-making behind the treatment choices, with their benefits and risks.

Refining the Chemotherapy Approach for Older Patients With Colon Cancer

Population studies support an increased incidence of most cancers among older adults. Colorectal cancer has high prevalence in the aging population, with a median age of 69 years at diagnosis and 74 years at death. The vast majority of patients with colon cancer (CC) will require chemotherapy treatments during their disease course, challenging oncologists with the task of tailoring therapy for older patients with CC in the face of limited evidence-based data to guide them. Factors such as comorbidity, performance status, cognitive function, and social support may affect decision making and complicate tolerance of any recommended therapy. In recent years, attention to the specific needs of the aging population with cancer has given rise to the field of geriatric oncology in general, and has generated an increasing fund of knowledge on which to base chemotherapy delivery for this specific population of patients with CC. This article will review the available data specifically for chemotherapy management of older patients with CC in the postoperative and metastatic settings.

Inflammation and insulin/IGF-1 resistance as the possible link between obesity and neurodegeneration

Obesity is a growing epidemic that contributes to several brain disorders including Alzheimer's, Parkinson's, and Huntington's diseases. Obesity could promote these diseases through several different mechanisms. Here we review evidence supporting the involvement of two recently recognized factors linking obesity with neurodegeneration: the induction of pro-inflammatory cytokines and onset of insulin and insulin-like growth factor 1 (IGF-1) resistance. Excess peripheral pro-inflammatory mediators, some of which can cross the blood brain barrier, may trigger neuroinflammation, which subsequently exacerbates neurodegeneration. Insulin and IGF-1 resistance leads to weakening of neuroprotective signaling by these molecules and can contribute to onset of neurodegenerative diseases.

Risk of gastrointestinal events with sorafenib, sunitinib and pazopanib in patients with solid tumors: a systematic review and meta-analysis of clinical trials

Gastrointestinal (GI) events have been described with sorafenib, sunitinib and pazopanib in cancer patients. We performed an up-to-date meta-analysis to determine the incidence and relative risk (RR) in patients with cancer treated with these agents. PubMed databases were searched for articles published till May 2013. Eligible studies were selected according to PRISMA statement. Summary incidence, RR, and 95% CIs were calculated using random-effects or fixed-effects models based on the heterogeneity of selected studies. A total of 6,447 patients were available for the meta-analysis; 2,260 had renal cell carcinoma (RCC) and 4,187, 1,691 non-small cell lung cancers, 599 hepatocellular cancers, 1,066 breast cancers, 165 neuroendocrine tumors, 304 gastrointestinal stromal tumors and 362 soft tissue sarcomas. Diarrhea was the most common GI event. When stratified by tumor type (RCC vs. non-RCC), the difference among the incidences of GI events was significant for diarrhea (p < 0.001) and vomiting (p = 0.006), that resulted higher in RCC patients. In RCC patients, sorafenib registered the lower incidence and RR of all grades GI events. The difference was statistically significant for sorafenib versus sunitinib-related all and high-grade events (p < 0.001) and for sorafenib versus pazopanib all grades GI events (p < 0.001) and high-grade anorexia (p < 0.001). Treatment with VEGFR TKIs sorafenib, sunitinib and pazopanib is associated with a significant increase in the risk of GI events in patients with cancer, and frequent clinical monitoring should be emphasized when managing these three and newer VEGFR TKIs.

Peritoneal surface disease with synchronous hepatic involvement treated with Cytoreductive Surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC)

BACKGROUND

Patients with peritoneal surface disease (PSD) often present with synchronous hepatic involvement (HI). The impact of addressing the hepatic component during CRS/HIPEC on operative and survival outcomes is not clearly defined.

METHODS

A prospective database of 1,067 procedures was reviewed based on primary tumor, performance status, resection status, type of liver involvement (superficial or parenchymal) and hepatic resection, morbidity, mortality, and overall survival.

RESULTS

There were 108 (10 %) CRS/HIPEC procedures performed with synchronous liver debulking in 99 patients with PSD from 27 (33 %) appendiceal and 32 (39 %) colorectal primary lesions. Ninety percent of patients underwent subsegmental hepatic resection, whereas 22 % had disease with hepatic parenchymal involvement. Median intensive care unit (ICU) and hospital stay were 3.5 and 13.6 days, respectively. Clavien grade III/IV morbidity was similar for patients with or without resected HI (18.9 vs. 22.5 %; p = 0.39). The 30-day mortality rate was 6.5 and 2.8 % (p = 0.07) for patients with and without resected HI, respectively. The median survival for all patients with low-grade appendiceal cancer was 42.1 months with resected HI and 95.5 months without HI (p = 0.03). Median survival for colorectal cancer patients after complete cytoreduction was 21.2 months with HI versus 33.6 months without HI (p = 0.03).

CONCLUSIONS

Synchronous resection of limited HI does not increase the morbidity or mortality of CRS/HIPEC procedures. The survival benefit, although still meaningful, was less for patients with HI. Resectable low volume HI in patients with PSD from colon and appendiceal primary lesions should not be considered a contraindication for CRS/HIPEC procedures.

Personalizing medicine for metastatic colorectal cancer: current developments

Metastatic colorectal cancer (mCRC) is still one of the tumor types with the highest incidence and mortality. In 2012, colorectal cancer was the second most prevalence cancer among males (9%) and the third among females (8%). In this disease, early diagnosis is important to improve treatment outcomes. However, at the time of diagnosis, about one quarter of patients already have metastases, and overall survival of these patients at 5-years survival is very low. Because of these poor statistics, the development of new drugs against specific targets, including the pathway of angiogenesis, has witnessed a remarkable increase. So, targets therapies through epidermal growth factor and its receptor and also KRAS pathways modulation acquired a main role whether in association with standard chemotherapy and radiotherapy. With the current knowledge in the field of molecular biology, including genetic mutations and polymorphisms, we know better why patients respond so differently to the same treatments. So, in the future we can develop increasingly personalized treatments to the patient and not the disease. This review aims to summarize some molecular pathways and their relation to tumor growth, as well as novel targeted developing drugs and recently approved for mCRC.

Rationally designed treatment for metastatic colorectal cancer: current drug development strategies

The therapeutic landscape of metastatic colorectal cancer (mCRC) has changed substantially with the emergence of new molecularly targeted agents (MTA) used as single agents or alongside standard chemotherapy. The use of these MTAs extended the overall survival of patients with mCRC to a level that current chemotherapeutics alone could not achieve. In addition, improvement in surgical techniques and ablation modalities offer cure to a limited subset of patients with mCRC and MTAs have been found to have a significant role here too, as they aid resectability. However, for the majority of patients, mCRC remains an invariably incurable disease necessitating continued courses of combined treatment modalities. During the course of these treatments, either cytotoxic or biological, cancer cells maintain their ability to acquire mitogenic mutations which render them resistant to treatment. Key challenges remain to identify appropriate subsets of patients who will most likely benefit from these new MTAs and effectively select these based on validated biomarkers. Moreover, better knowledge of the biology of colorectal cancer and the mechanisms via which it bypasses blockade of known signalling pathways will help us design better and more rational sequencing of these treatments, so that we can maximise the survivorship of mCRC patients. This review outlines treatment strategies for known molecular alterations with new MTAs and highlights some promising strategies.

Real-world study of everolimus in advanced progressive neuroendocrine tumors

Everolimus is a valid therapeutic option for neuroendocrine tumors (NETs); however, data in a real-world setting outside regulatory trials are sparse. The aim of this study was to determine everolimus tolerability and efficacy, in relation to previous treatments, in a compassionate use program. A total of 169 patients with advanced progressive NETs treated with everolimus were enrolled, including 85 with pancreatic NETs (pNETs) and 84 with nonpancreatic NETs (non-pNETs). Previous treatments included somatostatin analogs (92.9%), peptide receptor radionuclide therapy (PRRT; 50.3%), chemotherapy (49.7%), and PRRT and chemotherapy (22.8%). Overall, 85.2% of patients experienced adverse events (AEs), which were severe (grade 3-4) in 46.1%. The most frequent severe AEs were pneumonitis (8.3%), thrombocytopenia (7.7%), anemia (5.3%), and renal failure (3.5%). In patients previously treated with PRRT and chemotherapy, a 12-fold increased risk for severe toxicity was observed, with grade 3-4 AEs reported in 86.8% (vs. 34.3% in other patients). In addition, 63.3% of patients required temporarily everolimus discontinuation due to toxicity. Overall, 27.8% of patients died during a median follow-up of 12 months. Median progression-free survival (PFS) and overall survival (OS) were 12 months and 32 months, respectively. Similar disease control rates, PFS, and OS were reported in pNETs and non-pNETs. In the real-world setting, everolimus is safe and effective for the treatment of NETs of different origins. Higher severe toxicity occurred in patients previously treated with systemic chemotherapy and PRRT. This finding prompts caution when using this drug in pretreated patients and raises the issue of planning for everolimus before PRRT and chemotherapy in the therapeutic algorithm for advanced NETs.

Recognizing and managing left ventricular dysfunction associated with therapeutic inhibition of the vascular endothelial growth factor signaling pathway

OPINION STATEMENT

Therapeutic inhibition of the vascular endothelial growth factor (VEGF) signaling pathway (VSP) is increasingly employed in the contemporary treatment of many cancer types. VSP inhibitors include the anti-VEGF monoclonal antibody (bevacizumab), soluble VEGF receptors (VEGF Trap), and small molecule tyrosine kinase inhibitors (TKIs) targeting the intracellular kinase domain of VEGF receptors. These agents are associated with cardiovascular toxicities such as hypertension, thrombosis, myocardial ischemia, and left ventricular (LV) dysfunction. Data on VSP inhibitor-associated LV dysfunction are largely limited to retrospective studies. Prospective studies are needed to establish the clinical significance of VSP inhibitor-associated LV dysfunction in the general population. Pre-clinical models of VSP inhibitor-associated LV dysfunction have identified mechanisms of cardiotoxicity and may improve our understanding of the pathophysiology underlying other cardiomyopathies. This review provides an overview of LV dysfunction that can occur in patients treated with VSP inhibitors. Potential strategies for clinical detection and management of this cardiotoxicity are explored, while acknowledging that currently available data specific to VSP-inhibitor LV dysfunction are limited. Avenues for future research are suggested.

Aspirin inhibits cell viability and mTOR downstream signaling in gastroenteropancreatic and bronchopulmonary neuroendocrine tumor cells

AIM: To investigate the effect of aspirin on neuroendocrine tumor (NET) cell growth and signaling in vitro.

METHODS: Human pancreatic BON1, bronchopulmonary NCI-H727 and midgut GOT1 neuroendocrine tumor cells were treated with different concentrations of aspirin (from 0.001 to 5 mmol/L), and the resulting effects on metabolic activity/cell proliferation were measured using cell proliferation assays and SYBR-DNA-labeling after 72, 144 and 216 h of incubation. The effects of aspirin on the expression and phosphorylation of several critical proteins that are involved in the most common intracellular growth factor signaling pathways (especially Akt protein kinase B) and mammalian target of rapamycin (mTOR) were determined by Western blot analyses. Propidium iodide staining and flow cytometry were used to evaluate changes in cell cycle distribution and apoptosis. Statistical analysis was performed using a 2-tailed Student’s t-test to evaluate the proliferation assays and cell cycle analyses. The results are expressed as the mean ± SD of 3 or 4 independently performed experiments. Statistical significance was set at P < 0.05.

RESULTS: Treatment with aspirin suppressed the viability/proliferation of BON1, NCI-H727 and GOT1 cells in a time- and dose-dependent manner. Significant effects were observed at starting doses of 0.5-1 mmol/L and peaked at 5 mmol/L. For instance, after treatment with 1 mmol/L aspirin for 144 h, the viability of pancreatic BON1 cells decreased to 66% ± 13% (P < 0.05), the viability of bronchopulmonary NCI-H727 cells decreased to 53% ± 8% (P < 0.01) and the viability of midgut GOT1 cells decreased to 89% ± 6% (P < 0.01). These effects were associated with a decreased entry into the S phase, the induction of the cyclin-dependent kinase inhibitor p21 and reduced expression of cyclin-dependent kinase 4 and cyclin D3. Aspirin suppressed mTOR downstream signaling, evidenced by the reduced phosphorylation of the mTOR substrates 4E binding protein 1, serine/threonine kinase P70S6K and S6 ribosomal protein and inhibited glycogen synthase kinase 3 activity. We observed the (compensatory) activation of tuberous sclerosis 2, the serine/threonine specific protein kinase AKT and extracellular signal-regulated kinases.

CONCLUSION: Aspirin demonstrates promising anticancer properties for NETs in vitro. Further preclinical and clinical studies are needed.

Regorafenib-induced hyperammonemic encephalopathy

WHAT IS KNOWN AND OBJECTIVE

Regorafenib improves progression-free survival as a late-line treatment for patients with metastatic gastrointestinal stromal tumour (GIST). As a multitargeted tyrosine kinase inhibitor (TKI), the expected adverse events of regorafenib are similar to those reported with imatinib, sunitinib or sorafenib. We report the first case of hyperammonemic encephalopathy related to regorafenib in a patient with metastatic GIST.

CASE SUMMARY

A 61-year-old man maintained on regorafenib for metastatic GIST presented with acute confusion. Discontinuation of regorafenib led to complete resolution of confusion, which later recurred with hyperammonemia on recommencing regorafenib. Cessation of regorafenib and normalization of hyperammonemia then resulted in resolution of confusion.

WHAT IS NEW AND CONCLUSIONS

Regorafenib withdrawal and recommencement had influenced the confusional state and hyperammonemia in this patient. There is a probable relationship between regorafenib and metabolic encephalopathy. There are case reports of similar encephalopathy thought to be induced by other multitargeted TKI, and, as such, a class effect could be postulated.

Lessons learned from adult clinical experience to inform evaluations of VEGF pathway inhibitors in children with cancer

Agents targeting the vascular endothelial growth factor (VEGF) pathway have been studied in adults with cancer for nearly two decades. It is important to assess the lessons learned from this adult experience and to see how these lessons can help inform pediatric development of agents in this class. The benefit achieved from the use of VEGF pathway targeted agents for adult cancers has primarily been to delay for several months disease progression and less commonly time to death for conditions in which cure is not a reasonable expectation. VEGF pathway targeted agents have shown no efficacy when applied in the adjuvant setting. For adults with advanced cancer, prolongation of survival by 2-3 months is considered an important achievement in some settings. However, the primary goal of pediatric oncology clinical research is to identify treatments that allow children to be cured of their cancer and to grow to adulthood without treatment-induced limitations that lower their quality of survival. An important question for the pediatric oncology research community, pharmaceutical companies, and regulatory agencies to address in planning for future clinical trials is whether existing data support a role for VEGF pathway targeted agents in contributing to a therapeutic pathway to cure for children with cancer.

SIR-Spheres® radioembolization in the management of metastatic colorectal cancer: a medical oncology perspective

SUMMARY 

Despite of the recent advances in personalized medicine, the majority of patients with metastatic colorectal cancer still succumb to disease progression, with liver failure constituting one of the most common causes of death. Recently, selective internal radioembolization has emerged as a new treatment option in patients with liver predominant disease. The concurrent administration of yttrium-90 (Y-90) SIR-Spheres® (SIRTEX, Sydney, Australia) microspheres and chemotherapy has been linked to significant improvements in response rate, time to intrahepatic tumor progression and overall survival. In this manuscript, the author provides his personal perspective on the current clinical evidence in support of SIR-Spheres liver embolization and reflects on the potential of this treatment in various stages of treatment of metastatic colorectal cancer.

Neuroendocrine tumors of the lung: a comprehensive overview

A total of 25% of neuroendocrine tumors originate in the lung. Still, typical and atypical carcinoids of the lung are rare, accounting for only 1–2% of all lung cancers. Distant metastases are infrequent, occurring in 2–14% of cases. The mainstay of treatment of local disease is surgery. In advanced disease there are no antiproliferative agents approved for carcinoids of the lung. None of the currently available drugs provide a cure. There are several treatment options, such as somatostatin analogs, mTOR inhibition, inhibitors of angiogenesis, systemic chemotherapy and radiolabeled somatostatin analogs. Interpretation of the data is complicated, since it mainly consists of small (retrospective) Phase II studies. Fortunately, randomized Phase II and III studies are underway. This article emphasizes the specific features of neuroendocrine tumors in the lung and focuses on the treatment in advanced disease.

Risk of gastrointestinal perforation in cancer patients treated with aflibercept: a systematic review and meta-analysis

Gastrointestinal (GI) perforation is a serious adverse event associated with aflibercept, a novel vascular endothelial growth factor (VEGF)-targeted agent currently approved as second-line treatment for previously treated metastatic colorectal cancer, but the incidence and risk of GI perforation associated with aflibercept has not been well determined. We thus conducted this meta-analysis to investigate the overall incidence and risk of developing GI perforation associated with aflibercept. Databases from PubMed, Web of Science, and abstracts presented at American Society of Clinical Oncology (ASCO) and European Society of Medical Oncology (ESMO) meeting up to January, 2014 were searched to identify relevant studies. Eligible studies included prospective phase II and III trials evaluating aflibercept in cancer patients with adequate data on GI perforation. Statistical analyses were conducted to calculate the summary incidence, odds ratio, and 95% confidence intervals (CIs) by using either random effects or fixed effect models according to the heterogeneity of included studies. A total of 4,101 patients with a variety of solid tumors from eight clinical trials were included in our analysis. The incidence of GI perforation associated with aflibercept was 1.9% (95%CI, 1.0-3.8%), with a mortality of 10.8% (95%CI, 4.1-25.5%). In addition, patients treated with aflibercept had a significantly increased risk of developing all-grade (OR 3.76; 95%CI, 1.94-7.25; p < 0.001) and high-grade GI (OR 4.14; 95%CI; 2.12-8.06; p < 0.001) perforation compared with patients treated with control medication. No evidence of publication bias was observed. The use of aflibercept is associated with a significantly increased risk of GI perforation compared to controls.

Targeted therapy in older patients with solid tumors

The introduction of targeted therapy has ushered in the era of personalized medicine in cancer therapy. The increased understanding of tumor heterogeneity has led to the determination of specific targets that can be exploited in treatment. This review highlights approved drugs in different therapeutic classes, including tyrosine kinase inhibitors, mammalian target of rapamycin inhibitors, drugs targeted to the human epidermal growth factor receptor 2, BRAF-mutation targeted drugs, anti-epidermal growth factor receptor inhibitors, and anti-vascular endothelial growth factor therapy. There have not been elderly patient-specific trials of these therapies. Most of the data are extrapolated from larger trials in which older patients generally were a fraction of the participants. Therapeutic recommendations are made on the basis of this analysis with the recognition that the older clinical trial participants may not be representative of patients seen in daily practice. Patient selection and geriatric evaluation are critical for appropriate drug selection, dosing, and monitoring. With care, these therapies are a major step forward in the safe and effective treatment of older patients with cancer.

Variability of Ki67 labeling index in multiple neuroendocrine tumors specimens over the course of the disease

BACKGROUND

The Ki67-LI is a valid surrogate for biologic behavior of neuroendocrine tumors (NETs), with higher levels associated with aggressive behavior. The World Health Organization (WHO) classifies NETs according to Ki67-LI (G1: <3%; G2 : 3-20%; G3: >20%). Little is known about the evolution of NETs histologic characteristics over the disease course. We sought to evaluate variations in Ki67-LI throughout NETs disease course.

METHODS

We retrospectively reviewed the Sunnybrook Odette Cancer Center NET database for patients with multiple pathology specimens. Primary outcome was the WHO NET class based on Ki67-LI for each specimen. We assessed change in WHO class between specimens.

RESULTS

Forty-three patients were retrieved, of which 39 had specimens from the primary tumor and a metastatic focus, and 4 had specimens from multiple metastatic foci. Sixteen (37.0%) were identified with Ki67-LI falling in different WHO classes on distinct biopsies. For 12 (75.0%) of those 16 patients, Ki67-LI showed enough variability for WHO class to be upstaged: 5 (31%) from G1 to G2, 2 (13%) from G2 to G3, and 5 (31%) from G1 to G3.

CONCLUSION

When multiple pathology specimens were available, Ki67-LI varied throughout NETs disease course, with a majority of cases upgraded to a higher WHO class. If confirmed, this finding may have implications in how neuroendocrine tumors are monitored and treated. Further research is warranted to confirm these findings, understand better the underlying mechanisms of Ki67 variability, and define its relationship to prognosis.

The multifaceted activity of VEGF in angiogenesis - Implications for therapy responses

Vascular endothelial growth factor (VEGF) is a key growth factor driving angiogenesis (i.e. the formation of new blood vessels) in health and disease. Pharmacological blockade of VEGF signaling to inhibit tumor angiogenesis is clinically approved but the survival benefit is limited as patients invariably acquire resistance. This is partially mediated by the intrinsic flexibility of tumor cells to adapt to VEGF-blockade. However, it has become clear that tumor stromal cells also contribute to the resistance. Originally, VEGF was thought to specifically target endothelial cells (ECs) but it is now clear that many stromal cells also respond to VEGF signaling, making anti-VEGF therapy more complex than initially anticipated. A more comprehensive understanding of the complex responses of stromal cells to VEGF-blockade might inform the design of improved anti-angiogenic agents.

Which strategy after first-line therapy in advanced colorectal cancer?

Second-line therapy for advanced colorectal cancer is an integral part of the treatment strategy that needs to be set from the beginning for each patient, bearing in mind the expected toxicities of chosen treatments, the patient's clinical condition, comorbidities, preferences, the aims of the treatment and the molecular status. Furthermore, the distinction between lines of therapy is no longer absolute. The perspective of “continuum of care” includes switching chemotherapy prior to disease progression, maintenance therapy, drug "holidays" if needed, surgical resection of metastases in selected patients, and seems to allow a tailored treatment, in which patients are more likely to benefit from exposure to all active agents, which is known to correlate with overall survival. The scenario of second-line treatment has changed dramatically over the years and could currently benefit from several options including chemotherapy with a single agent or in combination and the addition of molecular-targeted agents developed in the last decade, such as epidermal growth factor receptor antibodies (cetuximab, panitumumab) and vascular endothelial growth factor-targeting agents (bevacizumab, aflibercept), with the possibility of bevacizumab use even beyond first progression. The purpose of this review is to summarize the most important scientific data supporting the use of chemotherapy and the new biologic agents in the second-line setting in advanced colorectal cancer.

Targeting angiogenesis and tumor microenvironment in metastatic colorectal cancer: role of aflibercept

In the last decades, we have progressively observed an improvement in therapeutic options for metastatic colorectal cancer (mCRC) treatment with a progressive prolongation of survival. mCRC prognosis still remains poor with low percentage of 5-year survival. Targeted agents have improved results obtained with standard chemotherapy. Angiogenesis plays a crucial role in colorectal cancer growth, proliferation, and metastasization and it has been investigated as a potential target for mCRC treatment. Accordingly, novel antiangiogenic targeted agents bevacizumab, regorafenib, and aflibercept have been approved for mCRC treatment as the result of several phase III randomized trials. The development of a tumor permissive microenvironment via the aberrant expression by tumor cells of paracrine factors alters the tumor-stroma interactions inducing an expansion of proangiogenic signals. Recently, the VELOUR study showed that addition of aflibercept to FOLFIRI regimen as a second-line therapy for mCRC improved significantly OS, PFS, and RR. This molecule represents a valid second-line therapeutic option and its peculiar ability to interfere with placental growth factor (PlGF)/vascular endothelial growth factor receptor 1 (VEGFR1) axis makes it effective in targeting angiogenesis, inflammatory cells and in overcoming resistances to anti-angiogenic first-line treatment. Here, we discuss about Aflibercept peculiar ability to interfere with tumor microenvironment and angiogenic pathway.