Activating mutations within the EGFR kinase domain: a molecular predictor of disease-free survival in resected pulmonary adenocarcinoma

Molecular testing guideline for selection of lung cancer patients for EGFR and ALK tyrosine kinase inhibitors: guideline from the College of American Pathologists, International Association for the Study of Lung Cancer, and Association for Molecular Pathology

OBJECTIVE

To establish evidence-based recommendations for the molecular analysis of lung cancers that are required to guide EGFR- and ALK-directed therapies, addressing which patients and samples should be tested, and when and how testing should be performed.

PARTICIPANTS

Three cochairs without conflicts of interest were selected, one from each of the 3 sponsoring professional societies: College of American Pathologists, International Association for the Study of Lung Cancer, and Association for Molecular Pathology. Writing and advisory panels were constituted from additional experts from these societies.

EVIDENCE

Three unbiased literature searches of electronic databases were performed to capture published articles from January 2004 through February 2012, yielding 1533 articles whose abstracts were screened to identify 521 pertinent articles that were then reviewed in detail for their relevance to the recommendations. EVIDENCE was formally graded for each recommendation.

CONSENSUS PROCESS

Initial recommendations were formulated by the cochairs and panel members at a public meeting. Each guideline section was assigned to at least 2 panelists. Drafts were circulated to the writing panel (version 1), advisory panel (version 2), and the public (version 3) before submission (version 4).

CONCLUSIONS

The 37 guideline items address 14 subjects, including 15 recommendations (evidence grade A/B). The major recommendations are to use testing for EGFR mutations and ALK fusions to guide patient selection for therapy with an epidermal growth factor receptor (EGFR) or anaplastic lymphoma kinase (ALK) inhibitor, respectively, in all patients with advanced-stage adenocarcinoma, regardless of sex, race, smoking history, or other clinical risk factors, and to prioritize EGFR and ALK testing over other molecular predictive tests. As scientific discoveries and clinical practice outpace the completion of randomized clinical trials, evidence-based guidelines developed by expert practitioners are vital for communicating emerging clinical standards. Already, new treatments targeting genetic alterations in other, less common driver oncogenes are being evaluated in lung cancer, and testing for these may be addressed in future versions of these guidelines.

Molecular testing guideline for selection of lung cancer patients for EGFR and ALK tyrosine kinase inhibitors: guideline from the College of American Pathologists, International Association for the Study of Lung Cancer, and Association for Molecular Pathology

OBJECTIVE

To establish evidence-based recommendations for the molecular analysis of lung cancers that are that are required to guide EGFR- and ALK-directed therapies, addressing which patients and samples should be tested, and when and how testing should be performed.

PARTICIPANTS

Three cochairs without conflicts of interest were selected, one from each of the 3 sponsoring professional societies: College of American Pathologists, International Association for the Study of Lung Cancer, and Association for Molecular Pathology. Writing and advisory panels were constituted from additional experts from these societies.

EVIDENCE

Three unbiased literature searches of electronic databases were performed to capture articles published published from January 2004 through February 2012, yielding 1533 articles whose abstracts were screened to identify 521 pertinent articles that were then reviewed in detail for their relevance to the recommendations. Evidence was formally graded for each recommendation.

CONSENSUS PROCESS

Initial recommendations were formulated by the cochairs and panel members at a public meeting. Each guideline section was assigned to at least 2 panelists. Drafts were circulated to the writing panel (version 1), advisory panel (version 2), and the public (version 3) before submission (version 4).

CONCLUSIONS

The 37 guideline items address 14 subjects, including 15 recommendations (evidence grade A/B). The major recommendations are to use testing for EGFR mutations and ALK fusions to guide patient selection for therapy with an epidermal growth factor receptor (EGFR) or anaplastic lymphoma kinase (ALK) inhibitor, respectively, in all patients with advanced-stage adenocarcinoma, regardless of sex, race, smoking history, or other clinical risk factors, and to prioritize EGFR and ALK testing over other molecular predictive tests. As scientific discoveries and clinical practice outpace the completion of randomized clinical trials, evidence-based guidelines developed by expert practitioners are vital for communicating emerging clinical standards. Already, new treatments targeting genetic alterations in other, less common driver oncogenes are being evaluated in lung cancer, and testing for these may be addressed in future versions of these guidelines.

Molecular testing guideline for selection of lung cancer patients for EGFR and ALK tyrosine kinase inhibitors: guideline from the College of American Pathologists, International Association for the Study of Lung Cancer, and Association for Molecular Pathology

OBJECTIVE

To establish evidence-based recommendations for the molecular analysis of lung cancers that are required to guide EGFR- and ALK-directed therapies, addressing which patients and samples should be tested, and when and how testing should be performed.

PARTICIPANTS

Three cochairs without conflicts of interest were selected, one from each of the 3 sponsoring professional societies: College of American Pathologists, International Association for the Study of Lung Cancer, and Association for Molecular Pathology. Writing and advisory panels were constituted from additional experts from these societies.

EVIDENCE

Three unbiased literature searches of electronic databases were performed to capture articles published from January 2004 through February 2012, yielding 1533 articles whose abstracts were screened to identify 521 pertinent articles that were then reviewed in detail for their relevance to the recommendations. Evidence was formally graded for each recommendation.

CONSENSUS PROCESS

Initial recommendations were formulated by the cochairs and panel members at a public meeting. Each guideline section was assigned to at least 2 panelists. Drafts were circulated to the writing panel (version 1), advisory panel (version 2), and the public (version 3) before submission (version 4).

CONCLUSIONS

The 37 guideline items address 14 subjects, including 15 recommendations (evidence grade A/B). The major recommendations are to use testing for EGFR mutations and ALK fusions to guide patient selection for therapy with an epidermal growth factor receptor (EGFR) or anaplastic lymphoma kinase (ALK) inhibitor, respectively, in all patients with advanced-stage adenocarcinoma, regardless of sex, race, smoking history, or other clinical risk factors, and to prioritize EGFR and ALK testing over other molecular predictive tests. As scientific discoveries and clinical practice outpace the completion of randomized clinical trials, evidence-based guidelines developed by expert practitioners are vital for communicating emerging clinical standards. Already, new treatments targeting genetic alterations in other, less common driver oncogenes are being evaluated in lung cancer, and testing for these may be addressed in future versions of these guidelines.

Epidermal growth factor receptor inhibits colitis-associated cancer in mice

Inflammatory bowel disease (IBD) is a chronic illness caused by complex interactions between genetic and environmental factors that propagate inflammation and damage to the gastrointestinal epithelium. This state of chronic inflammation increases the risk for development of colitis-associated cancer in IBD patients. Thus, the development of targeted therapeutics that can disrupt the cycle of inflammation and epithelial injury is highly attractive. However, such biological therapies, including those targeting epidermal growth factor receptor pathways, pose a risk of increasing cancer rates. Using two mouse models of colitis-associated cancer, we found that epidermal growth factor receptor inactivation accelerated the incidence and progression of colorectal tumors. By modulating inflammation and epithelial regeneration, epidermal growth factor receptor optimized the response to chronic inflammation and limited subsequent tumorigenesis. These findings provide important insights into the pathogenesis of colitis-associated cancer and suggest that epidermal growth factor-based therapies for IBD may reduce long-term cancer risk.

The impact of initial gefitinib or erlotinib versus chemotherapy on central nervous system progression in advanced non-small cell lung cancer with EGFR mutations

PURPOSE

This retrospective study was undertaken to investigate the impact of initial gefitinib or erlotinib (EGFR tyrosine kinase inhibitor, EGFR-TKI) versus chemotherapy on the risk of central nervous system (CNS) progression in advanced non-small cell lung cancer (NSCLC) with EGFR mutations.

EXPERIMENTAL DESIGN

Patients with stage IV or relapsed NSCLC with a sensitizing EGFR mutation initially treated with gefitinib, erlotinib, or chemotherapy were identified. The cumulative risk of CNS progression was calculated using death as a competing risk.

RESULTS

One hundred and fifty-five patients were eligible (EGFR-TKI: 101, chemotherapy: 54). Twenty-four patients (24%) in the EGFR-TKI group and 12 patients (22%) in the chemotherapy group had brain metastases at the time of diagnosis of advanced NSCLC (P = 1.000); 32 of the 36 received CNS therapy before initiating systemic treatment. Thirty-three patients (33%) in the EGFR-TKI group and 26 patients (48%) in the chemotherapy group developed CNS progression after a median follow-up of 25 months. The 6-, 12-, and 24-month cumulative risk of CNS progression was 1%, 6%, and 21% in the EGFR-TKI group compared with corresponding rates of 7%, 19%, and 32% in the chemotherapy group (P = 0.026). The HR of CNS progression for upfront EGFR-TKI versus chemotherapy was 0.56 [95% confidence interval (CI), 0.34-0.94].

CONCLUSIONS

Our data show lower rates of CNS progression in EGFR-mutant advanced NSCLC patients initially treated with an EGFR-TKI compared with upfront chemotherapy. If validated, our results suggest that gefitinib and erlotinib may have a role in the chemoprevention of CNS metastases from NSCLC.

Metastatic brain tumors from non-small cell lung cancer with EGFR mutations: distinguishing influence of exon 19 deletion on radiographic features

INTRODUCTION

Miliary brain metastasis is a rarity and refers to the presence of numerous small tumors in a perivascular distribution without intraparenchymal invasion and focal edema. Although the presence of epidermal growth factor receptor (EGFR) mutation and good response to gefitinib have been reported in non-small cell lung cancer (NSCLC) patients with miliary brain metastases, the influence of the EGFR mutations on the radiographic features remains unclear.

PATIENTS AND METHODS

All NSCLC patients with synchronous brain metastases detected at the time of a new diagnosis of NSCLC from March 2005 through May 2011 were divided according to EGFR mutation status. The number of brain tumors, size of the largest brain tumors, and size of peritumoral brain edema were compared among the groups.

RESULTS

Fifty-seven patients who met the criteria were divided into three groups: wild-type EGFR group (31 patients), exon 19 deletion group (18 patients), and exon 21 point mutation group (8 patients). The exon 19 deletion group had more multiple and smaller brain tumors with smaller peritumoral brain edema than did the wild-type group (P = 0.024, P = 0.0016, and P = 0.0036, respectively). The exon 21 point mutation group showed no significant difference in any of the radiographic values when compared with the wild-type group.

CONCLUSION

Our results indicate that NSCLC patients with the exon 19 deletion have such a peculiar pattern of brain metastases as multiple small metastases with small brain edema. This metastatic pattern may be similar to that of miliary brain metastases. Because it is unclear whether or not severe neurologic symptoms develop during their clinical courses like miliary brain metastases, regular evaluation with brain magnetic resonance imaging (MRI) should be considered, regardless of the presence of neurologic symptoms. Accumulation of knowledge about specific pattern of brain metastasis will help approach to "individual" management.

Targeted therapy for brain metastases

The prevention and treatment of brain metastases is an increasingly important challenge in oncology. Improved understanding of the molecular pathogenesis of a number of cancers has led to the development of highly active targeted therapies for patients with specific oncogenic events. Such therapies include EGFR inhibitors for lung cancer, HER2/neu inhibitors for breast cancer, and BRAF inhibitors for melanoma. This review will discuss the development of these targeted therapy approaches, existing data about their role in the management of brain metastasis, and opportunities and challenges for future research in this critical area.

Tumor epidermal growth factor receptor genotype and depression in stage IV non-small cell lung cancer

INTRODUCTION

Depression appears to be associated with worse survival from cancer, but underlying mechanisms for this association are unknown. In the present study, we explored the degree to which tumor genotype may be associated with depression in patients with non-small cell lung cancer (NSCLC). We examined differences in depression severity and rates of positive screens for major depressive disorder among newly diagnosed patients with stage IV NSCLC and known epidermal growth factor receptor (EGFR) genotype.

METHODS

Newly diagnosed patients (n = 53) with metastatic NSCLC attending an initial thoracic oncology consultation completed self-report questionnaires regarding demographics, smoking behavior, and depression before meeting with their oncologist. Biopsy samples were subsequently genotyped, including screening for EGFR mutations. We conducted a retrospective chart review to obtain clinical data, including tumor stage, performance status, and EGFR genotype.

RESULTS

Twelve patients (22.6%) tested positive for EGFR mutation. No EGFR mutation-positive cases met the screening criteria for major depressive disorder, in comparison with 29.3% of patients with wild-type EGFR (p = .03). Mutations of EGFR were also associated with lower depression severity than with wild-type EGFR, independent of gender, performance status, and smoking history (p < .05). This finding persisted for both the cognitive-affective and somatic domains of depression symptoms.

CONCLUSIONS

EGFR mutations were associated with lower depression severity and lower rates of probable major depressive disorder in patients with metastatic NSCLC, based on mood screening performed before results of genotyping were known. Findings support further work to explore the directionality of the associations and potential biological pathways to depression.

Development of central nervous system metastases in patients with advanced non-small cell lung cancer and somatic EGFR mutations treated with gefitinib or erlotinib

PURPOSE

Gefitinib and erlotinib can penetrate into the central nervous system (CNS) and elicit responses in patients with brain metastases (BM) from non-small cell lung cancer (NSCLC). However, there are incomplete data about their impact on the development and control of CNS metastases.

EXPERIMENTAL DESIGN

Patients with stage IIIB/IV NSCLC with somatic EGFR mutations initially treated with gefitinib or erlotinib were identified. The cumulative risk of CNS progression was calculated using death as a competing risk.

RESULTS

Of the 100 patients, 19 had BM at the time of diagnosis of advanced NSCLC; 17 of them received CNS therapy before initiating gefitinib or erlotinib. Eighty-four patients progressed after a median potential follow-up of 42.2 months. The median time to progression was 13.1 months. Twenty-eight patients developed CNS progression, 8 of whom had previously treated BM. The 1- and 2-year actuarial risk of CNS progression was 7% and 19%, respectively. Patient age and EGFR mutation genotype were significant predictors of the development of CNS progression. The median overall survival for the entire cohort was 33.1 months.

CONCLUSIONS

Our data suggest a lower risk of CNS progression in patients with advanced NSCLC and somatic EGFR mutations initially treated with gefitinib or erlotinib than published rates of 40% in historical series of advanced NSCLC patients. Further research is needed to distinguish between the underlying rates of developing CNS metastases between NSCLC with and without EGFR mutations and the impact of gefitinib and erlotinib versus chemotherapy on CNS failure patterns in these patients.