Patient considerations in metastatic colorectal cancer - role of panitumumab

Cardiovascular Risks with Epidermal Growth Factor Receptor (EGFR) Tyrosine Kinase Inhibitors and Monoclonal Antibody Therapy

PURPOSE OF REVIEW

Tyrosine kinase inhibitors (TKI) and monoclonal antibodies (mAbs) that target the epidermal growth factor receptor (EGFR) have changed the therapeutic landscape across a range of solid malignancies. However, there is little data regarding the cardiovascular (CV) impact of these agents. The purpose of this review is to discuss reported CV effects, pathophysiology, pre-treatment screening, diagnostic workup, and treatment recommendations in this patient population.

RECENT FINDINGS

It is apparent that CV events are not class dependent, and while infrequently reported in clinical trials, unique CV toxicity may occur with EGFR inhibitors, including structural, electrical, and vascular events. There remains an unmet need to fully elucidate the spectrum of CV events associated with EGFR inhibitors. Early CV screening, close clinical monitoring, coupled with a multidisciplinary approach between medical and cardio-oncology is needed to minimize the potentially detrimental impact of cardiotoxicity in this patient population.

Investigation of Cyclooxygenase-2 Gene Polymorphism in Patients with Gastric Cancer and Healthy Individuals in Northern Iran

Background: Gastric cancer is one of the most common types of cancer in the world. Cyclooxygenase-2 (COX-2) is a pro-inflammatory enzyme and an important mediator of tumor cell proliferation and angiogenesis. Objectives: The aim of this study was to investigate the relationship between COX-2 gene polymorphism and the risk of developing gastric cancer. Methods: This case-control study was carried out on 150 patients with gastric cancer and 150 healthy individuals. Genomic DNA was extracted using a modified method of protein precipitation at high salt concentrations. Polymorphisms of the COX-2 gene were investigated by polymerase chain reaction-restriction fragment length polymorphism analysis. Results: In this study, the frequency of GG genotype and CC genotype was significantly higher in patients with gastric cancer and healthy individuals, respectively (P < 0.05). However, the frequency of CC genotype did not significantly differ between the 2 study groups. Conclusions: We demonstrated that the homozygous GG genotype of COX-2 is significantly more frequent in patients with gastric cancer compared to healthy individuals. This could indicate the possible role of COX-2 in the development or progression of gastric cancer.

Personalized Medicine-Current and Emerging Predictive and Prognostic Biomarkers in Colorectal Cancer

Colorectal cancer (CRC) is the third most common cancer diagnosed worldwide and is heterogeneous both morphologically and molecularly. In an era of personalized medicine, the greatest challenge is to predict individual response to therapy and distinguish patients likely to be cured with surgical resection of tumors and systemic therapy from those resistant or non-responsive to treatment. Patients would avoid futile treatments, including clinical trial regimes and ultimately this would prevent under- and over-treatment and reduce unnecessary adverse side effects. In this review, the potential of specific biomarkers will be explored to address two key questions—1) Can the prognosis of patients that will fare well or poorly be determined beyond currently recognized prognostic indicators? and 2) Can an individual patient’s response to therapy be predicted and those who will most likely benefit from treatment/s be identified? Identifying and validating key prognostic and predictive biomarkers and an understanding of the underlying mechanisms of drug resistance and toxicity in CRC are important steps in order to personalize treatment. This review addresses recent data on biological prognostic and predictive biomarkers in CRC. In addition, patient cohorts most likely to benefit from currently available systemic treatments and/or targeted therapies are discussed in this review.

Current Update of Laboratory Molecular Diagnostics Advancement in Management of Colorectal Cancer (CRC)

Colorectal cancer (CRC) continues to be one of the most common cancers globally. The incidence has increased in developing countries in the past few decades, this could be partly attributed to aging populations and unhealthy lifestyles. While the treatment of CRC has seen significant improvement since the advent of target-specific therapies and personalized medicine, CRC is oftentimes detected at late or advanced stages, thereby reducing the efficacy of treatment. Hence, screening for early detection is still the key to combat CRC and to increase overall survival (OS). Considering that the field of medical diagnostics is moving towards molecular diagnostics, CRC can now be effectively screened and diagnosed with high accuracy and sensitivity. Depending on the tumor genotype and genetic profile of the individual, personalized treatments including tyrosine kinase inhibitor therapy and immunotherapy can be administered. Notably, there can be no one single treatment that is effective for all CRC patients due to the variation in tumor genetics, which highlights the importance of molecular diagnostics. This review provides insights on therapeutic modalities, molecular biomarkers, advancement of diagnostic technologies, and current challenges in managing CRC.

Treatment sequencing in metastatic colorectal cancer

Metastatic colorectal cancer (mCRC) remains incurable in most cases, but survival has improved with advances in cytotoxic chemotherapy and targeted agents. However, the optimal use and sequencing of these agents across multiple lines of treatment is unclear. Here, we review current treatment approaches and optimal treatment sequencing across the first-, second- and third-line settings in mCRC, including biological aspects affecting sequencing and rechallenge. Effective first-line therapy is a key determinant of treatment outcomes and should be selected after considering both clinical factors and biological markers, notably RAS and BRAF. The second-line regimen choice depends on the systemic therapies given in first-line. Anti-angiogenic agents (e.g. bevacizumab, ramucirumab and aflibercept) are indicated for most patients, whereas epidermal growth factor receptor (EGFR) inhibitors do not improve survival in the second-line setting. Molecular profiling is important in third-line treatment, with options in RAS wild-type patients including EGFR inhibitors (cetuximab or panitumumab), regorafenib and trifluridine/tipiracil. Immunotherapy with pembrolizumab or nivolumab ± ipilimumab may be considered for patients with high microsatellite instability disease. Targeting HER2/neu amplification shows promise for the subset of CRC tumours displaying this abnormality. Sequencing decisions are complicated by the potential for any treatment break or de-escalation to evoke a distinct clinical progression type. Ongoing trials are investigating the optimal sequencing and timing of therapies for mCRC. Molecular profiling has established new targets, and increasing knowledge of tumour evolution under drug pressure will possibly impact on sequencing.

Growth suppression of colorectal cancer expressing S492R EGFR by monoclonal antibody CH12

Colorectal cancer (CRC) is a common malignant tumor in the digestive tract, and 30%-85% of CRCs express epidermal growth factor receptors (EGFRs). Recently, treatments using cetuximab, also named C225, an anti-EGFR monoclonal antibody, for CRC have been demonstrated to cause an S492R mutation in EGFR. However, little is known about the biological function of S492R EGFR. Therefore, we attempted to elucidate its biological function in CRC cells and explore new treatment strategies for this mutant form. Our study indicated that EGFR and S492R EGFR accelerate the growth of CRC cells in vitro and in vivo and monoclonal antibody CH12, which specifically recognizes an EGFR tumor-specific epitope, can bind efficiently to S492R EGFR. Furthermore, mAb CH12 showed significantly stronger growth suppression activities and induced a more potent antibody-dependent cellular cytotoxicity effect on CRC cells bearing S492R EGFR than mAb C225. mAb CH12 obviously suppressed the growth of CRC xenografts with S492R EGFR mutations in vivo. Thus, mAb CH12 may be a promising therapeutic agent in treating patients with CRC bearing an S492R EGFR mutation.

A case of sigmoid colon adenocarcinoma diagnosed as facial cutaneous metastasis for survival after operation for 37 months

Cutaneous metastasis of an internal malignancy is uncommon and is estimated to occur in 0.7-9% of patients with internal cancer including autopsy cases. We would like to report a case of long survival of sigmoid colon adenocarcinoma diagnosed as an instance of facial cutaneous metastasis. A 68-year-old male was admitted to our hospital for a tumor mass on the left side of his cheek. In his past history, acute myocardial infarction had occurred 2 years earlier. He also had chronic renal failure and chronic obstructive pulmonary disease. Histologic findings from the biopsy sample of this facial lesion were moderately differentiated adenocarcinoma. Colonoscopy revealed a tumor 20 mm × 30 mm in diameter in the sigmoid colon. Histologic findings of the biopsy sample of this tumor also indicated moderately differentiated adenocarcinoma. The patient was diagnosed with sigmoid colon cancer with cutaneous metastasis to the face. We performed a sigmoidectomy with lymph node dissection and resection of the facial cutaneous metastasis. After being discharged, low dose chemotherapy was performed in consideration of the patient's renal function. Although long-term management of his general condition was provided, the patient died 37 months after surgery because of chronic heart failure.