Circulating free tumor-derived DNA to detect EGFR mutations in patients with advanced NSCLC: French subset analysis of the ASSESS study

Background

The non-interventional ASSESS study (NCT01785888) evaluated the utility of circulating free tumor-derived DNA (ctDNA) from plasma for epidermal growth factor receptor (EGFR) mutation testing in patients with advanced non-small-cell lung cancer (NSCLC), in a real-world setting across 56 centers in Europe and Japan. The high mutation status concordance between 1162 matched tissue/cytology and plasma samples (89%, sensitivity =46%, specificity =97%) suggested that ctDNA is a feasible sample for EGFR mutation analysis. We report data for the French subset of patients (pre-planned analysis).

Methods

Eligible patients (stage IIIA/B/IV locally advanced/metastatic treatment-naive advanced NSCLC) provided diagnostic tissue/cytology and plasma samples. DNA extracted from tissue/cytology samples was subjected to EGFR mutation testing as per local practice; a designated laboratory performed ctDNA extraction/mutation testing of plasma samples. The primary outcome was EGFR mutation status concordance between matched tumor and plasma samples.

Results

Of the 1,311 patients enrolled in the ASSESS trial, 145 were recruited from 9 centers in France. Tumor samples from 130 patients were collected and 126 were evaluable for EGFR mutation analysis. Activating EGFR mutations were identified in 13 of the 126 patient tumor samples (EGFR mutation frequency 10.3%). For plasma testing, 10 of the 145 samples tested were positive for EGFR mutations (EGFR mutation frequency 6.9%). EGFR mutation rate was significantly higher in never- versus ever-smokers (stepwise logistic regression: tumor, P<0.0001; plasma, P=0.0008). Mutation status concordance between 126 matched patient samples was 96.0% [121/126; 95% confidence intervals (CI), 91.0-98.7]. Of the 113 EGFR mutation-negative patient tissue samples, one tested plasma-positive; reanalysis of plasma via two different techniques confirmed the presence of a L858R mutation, indicating a tissue false-negative result. Based on these data, sensitivity of plasma testing was 64.3% (9/14; 95% CI, 35.1-87.2%) and its specificity was 100.0% (112/112; 95% CI, 96.8-100.0%).

Conclusions

Data confirm ctDNA as an alternative sample for EGFR mutation analysis in patients with advanced NSCLC.

Study KBP-2010-CPHG: Characteristics and management of 968 new cases of small-cell lung cancer (SCLC)

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Background: In recent years, many major advances have been made in non-small-cell lung cancer (NSCLC), and in particular in adenocarcinoma, but not in SCLC. In 2010, the French College of General Hospital Respiratory Physicians (CPHG) performed a prospective multicentre epidemiological study (KBP-2010-CPHG) to describe the baseline characteristics and management of all new cases of primary lung cancer and to evaluate survival. The present abstract reports results in SCLC patients. Methods: 7,051 patients ≥18 years presenting with a new case of primary lung cancer, histologically or cytologically diagnosed between 1 January and 31 December 2010 and managed in the respiratory department of one of the 104 general hospitals participating in the study, were included. A standardised form was completed for each patient. A steering committee checked data collection exhaustiveness. SCLC data were analysed separately. Results: There were 968 SCLC patients: mean age, 65.6 years (+/-10.6); 23.2% female; 4.4% non-smokers (11 % in women), 35.8% ex-smokers, 59.8% current smokers; 63.4% with performance status 0 or 1; 59.9% having lost weight within the previous 3 months (19.8% of whom had lost >10 kg). Main tumour characteristics at diagnosis were: 71.2% stage IV, 24.7% stage IIIA or IIIB, 4.1% of stage <III. 15.2% of patients received chemo-radiotherapy and 73.4% chemotherapy (86.2% platinum-based). Carboplatin was more commonly used in patients >70 (59.1%) than <70 years of age (40.9 %). One-year mortality was 64.2%. Compared with NSCLC patients, patients with SCLC more frequently were active smokers (59.8% vs.47.6%), lost weight (59.9% vs. 52.4%), and presented with stage IV tumour at diagnosis (71.2% vs. 58.3%); first line therapy was more frequently platinum-based chemotherapy (86.2% vs. 61.2%) and less frequently curative surgery (1.6% vs. 19%), and mortality was higher (64.2% vs. 55.2%). Conclusions: In 2010, prognosis remains poor in SCLC. Compared with NSCLC, it was more frequently associated with active smoking and stage IV disease, and showed a lower rate of surgery.

Allergies associated with body piercing and tattoos: a report of the Allergy Vigilance Network

Body piercing and tattooing are increasingly common. As well as the risk of infection and scarring, allergic reactions are also reported. This is the first multi-centre study to assess the frequency of consultations for allergy. Of the 138 allergologists who answered our two questionnaires, 7.9% reported allergic reactions associated with body piercing and 18.9% identified allergies associated with temporary henna-based tattoos. Contact eczema, rhinitis and urticaria were related to nickel allergy. Contact eczema, generalized eczema, pruritus and edema were caused by tattoos. In 20 out of 28 cases, sensitization to para-phenylenediamine (PPD) was observed. The authors review the literature, underscoring the risk of serious allergy to PPD, the need for long-term monitoring of the risk of skin lymphocytoma, the difficulties met during treatment and the necessity of regulating tattooing and body piercing practices.