Pathology and genetics of tumors of soft tissue and bone

Screening for Epidermal Growth Factor Receptor Mutations in Lung Cancer

Mutations in the epidermal growth factor receptor (EGFR) gene are commonly observed in non-small-cell lung cancer (NSCLC), particularly in tumors of adenocarcinoma (ADC) histology (NSCLC/ADC). Robust data exist regarding the prevalence of EGFR mutations in Western and Asian patients with NSCLC/ADC, yet there is a lack of data for patients of other ethnicities. This review collated available data with the aim of creating a complete, global picture of EGFR mutation frequency in patients with NSCLC/ADC by ethnicity. Worldwide literature reporting EGFR mutation frequency in patients with NSCLC/ADC was reviewed, to create a map of the world populated with EGFR mutation frequency by country (a 'global EGFR mutMap'). A total of 151 worldwide studies (n=33162 patients with NSCLC/ADC, of which 9749 patients had EGFR mutation-positive NSCLC/ADC) were included. There was substantial variation in EGFR mutation frequency between studies, even when grouped by geographic region or individual country. As expected, the Asia-Pacific NSCLC/ADC subgroup had the highest EGFR mutation frequency (47% [5958/12819; 87 studies; range 20%-76%]) and the lowest EGFR mutation frequency occurred in the Oceania NSCLC/ADC subgroup (12% [69/570; 4 studies; range 7%-36%]); however, comparisons between regions were limited due to the varying sizes of the patient populations studied. In all regional (geographic) subgroups where data were available, EGFR mutation frequency in NSCLC/ADC was higher in women compared with men, and in never-compared with ever-smokers. This review provides the foundation for a global map of EGFR mutation frequency in patients with NSCLC/ADC. The substantial lack of data from several large geographic regions of the world, notably Africa, the Middle East, Central Asia, and Central and South America, highlights a potential lack of routine mutation testing and the need for further investigations in these regions.

EGFR mutation incidence in non-small-cell lung cancer of adenocarcinoma histology: a systematic review and global map by ethnicity (mutMapII)

// Yue-Lun Zhang 1, 2 , Jin-Qiu Yuan 1, 2 , Kai-Feng Wang 3 , Xiao-Hong Fu 1, 2 , Xiao-Ran Han 1, 2 , Diane Threapleton 1 , Zu-Yao Yang 1, 2 , Chen Mao 1, 2 , Jin-Ling Tang 1, 2 1 Division of Epidemiology, The Jockey Club School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China 2 Shenzhen Municipal Key Laboratory for Health Risk Analysis, Shenzhen Research Institute of The Chinese University of Hong Kong, Shenzhen, Guangdong Province, China 3 Division of Epidemiology, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou, Guangdong Province, China Correspondence to: Chen Mao, email: maochen@cuhk.edu.hk Jin-Ling Tang, email: jltang@cuhk.edu.hk Keywords: non-small cell lung cancer, epidermal growth factor receptor, prevalence, systematic review, meta-analysis Received: May 17, 2016     Accepted: September 25, 2016     Published: October 12, 2016 ABSTRACT Objectives: Estimate the epidermal growth factor receptor ( EGFR ) mutation prevalence in all non-small cell lung cancer (NSCLC) patients and patient subgroups. Results: A total of 456 studies were included, reporting 30,466 patients with EGFR mutation among 115,815 NSCLC patients. The overall pooled prevalence for EGFR mutations was 32.3% (95% CI 30.9% to 33.7%), ranging from 38.4% (95% CI: 36.5% to 40.3%) in China to 14.1% (95% CI: 12.7% to 15.5%) in Europe. The pooled prevalence of EGFR mutation was higher in females (females vs. males: 43.7% vs. 24.0%; OR: 2.7, 95% CI: 2.5 to 2.9), non-smokers (non-smokers vs. past or current smokers: 49.3% vs. 21.5%; OR: 3.7, 95% CI: 3.4 to 4.0), and patients with adenocarcinoma (adenocarcinoma vs. non-adenocarcinoma: 38.0% vs. 11.7%; OR: 4.1, 95% CI: 3.6 to 4.8). Materials and Methods: PubMed, EMBASE, and the Cochrane Library were searched to June 2013. Eligible studies reported EGFR mutation prevalence and the association with at least one of the following factors: gender, smoking status and histology. Random-effects models were used to pool EGFR mutation prevalence data. Conclusion: This study provides the exact prevalence of EGFR mutations in different countries and NSCLC patient subgroups.

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The prevalence of EGFR mutation in patients with non-small cell lung cancer: a systematic review and meta-analysis

PURPOSEStandard first-line therapy for EGFR-mutant advanced non–small-cell lung cancer (NSCLC) is an epidermal growth factor receptor (EGFR)–directed oral tyrosine kinase inhibitor. Adding pemetrex...

https://ascopubs.org/doi/pdf/10.1200/JCO.19.01154

Gefitinib Versus Gefitinib Plus Pemetrexed and Carboplatin Chemotherapy in EGFR-Mutated Lung Cancer

Anaplastic lymphoma kinase ( ALK ) gene rearrangements are present in a small subset of non-small-cell lung cancers. ALK -positivity confers sensitivity to small-molecule ALK kinase inhibitors, such as crizotinib. The integration of crizotinib into standard treatment practice in NSCLC will rest on the widespread implementation of an effective screening system for newly diagnosed patients with NSCLC which is flexible enough to incorporate new targets as treatments are developed for them. Phase I and II studies of crizotinib in ALK -positive lung cancer have demonstrated significant activity and impressive clinical benefit, which led to its early approval by USFDA in 2011. Although crizotinib induces remissions and extends the lives of patients, there have been reports of emerging resistance to Crizotinib therapy. In this review, we discuss the history, mechanism of action, uses, adverse effects, dose modifications and future challenges and opportunities for patients with ALK -positive lung cancers.

Crizotinib: A comprehensive review.

Ewing's sarcoma/PNET are small round cell tumors showing a varying degree of neuroectodermal differentiation. They are one of the commonest tumors of childhood and occur in bone and within soft tissues. Traditionally, light microscopy with the aid of immunohistochemical stains was suitable for diagnosis. But now translocation analyses are being used not only for the diagnosis and classification of small round cell tumors, but to ascertain their prognostic significance, detect micrometastasis, and monitor minimal residual disease, with potential for targeted therapy. This article analyzes the pathology, biology, and molecular aspects of Ewing's sarcoma/PNET and discusses their clinical and therapeutic implications.

Pathology of Ewing's sarcoma/PNET: Current opinion and emerging concepts.

Background 
During the past decade, the incidence of EGFR mutation has been shown to vary across different ethnicities. It occurs at the rate of 10–15% in North Americans and Europeans, 19% in African-Americans, 20–30% in various East Asian series including Chinese, Koreans, and Japanese. Frequency of EGFR mutations in India however remains sparsely explored.


Methodology/Principal Findings 
We report 23% incidence of Epidermal growth factor receptor (EGFR) mutations in 907 Non small cell lung cancer (NSCLC) patients of Indian ethnicity, in contrast to 10–15% known in Caucasians and 27–62% among East Asians. In this study, EGFR mutations were found to be more common in never-smokers 29.4% as compared to smokers 15.3%. Consistent with other populations, mutation rates among adenocarcinoma-males were predominantly lower than females with 32% incidence. However unlike Caucasians, EGFR mutation rate among adenocarcinoma-never-smoker females were comparable to males suggesting lack of gender bias among never smokers likely to benefit from EGFR targeted therapy.


Conclusions/Significance 
This study has an overall implication for establishing relevance for routine EGFR mutation diagnostics for NSCLC patients in clinics and emphasizes effectiveness for adoption of EGFR inhibitors as the first line treatment among Indian population. The intermediate frequency of EGFR mutation among Indian population compared to Caucasians and East Asians is reminiscent of an ancestral admixture of genetic influence from Middle Easterners, Central Asians, and Europeans on modern- Indian population that may confer differential susceptibility to somatic mutations in EGFR.

/pdf/frequency-of-egfr-mutations-in-907-lung-adenocarcioma-4fy06r045i.pdf

Frequency of EGFR Mutations in 907 Lung Adenocarcioma Patients of Indian Ethnicity

Screening for EGFR mutation is a key molecular test for management of lung cancer patients. Outcome of patients with mutation receiving EGFR tyrosine kinase inhibitor is known to be better across different ethnic populations. However, frequency of EGFR mutations and the clinical response in most other ethnic populations, including India, remains to be explored. We conducted a retrospective analysis of Indian lung cancer patients who were managed with oral tyrosine kinase inhibitors. Majority of the patients in the study had adenocarcinoma and were non-smokers. 39/111 patients tested positive for EGFR kinase domain mutations determined by Taqman based real time PCR. The overall response to oral TKI therapy was 30%. Patients with an activating mutation of EGFR had a response rate of 74%, while the response rate in patients with wild type EGFR was 5%, which was a statistically significant difference. Progression free survival of patients with EGFR mutations was 10 months compared to 2 months for EGFR mutation negative patients. Overall survival was 19 months for EGFR mutation patients and 13 months for mutation negative patients. This study emphasizes EGFR mutation as an important predictive marker for response to oral tyrosine kinase inhibitors in the Indian population.

/pdf/egfr-mutations-in-indian-lung-cancer-patients-clinical-1wkatn6fu0.pdf

EGFR mutations in Indian lung cancer patients: clinical correlation and outcome to EGFR targeted therapy.

Chondromyxoid fibroma (CMF) can be confused with a malignant tumor because of its potential for recurrence and occasional nuclear atypia. This study of 10 cases of CMF comprises 6 men and 4 women, with a mean age of 24.3 years. Tibia was the preferred site of involvement. The histology showed lobulated chondromyxoid matrix with peripheral fibrosis. Two cases had local recurrences following intralesional excision. The study emphasizes that despite nuclear atypia and recurrences, CMF is a benign disease.

Saral Desai

Papers

Crizotinib: A comprehensive review.

Pathology of Ewing's sarcoma/PNET: Current opinion and emerging concepts.

Frequency of EGFR Mutations in 907 Lung Adenocarcioma Patients of Indian Ethnicity

EGFR mutations in Indian lung cancer patients: clinical correlation and outcome to EGFR targeted therapy.

Chondromyxoid fibromas: a study of 10 cases.