Overall survival in EGFR mutated non-small-cell lung cancer patients treated with afatinib after EGFR TKI and resistant mechanisms upon disease progression.

PURPOSE: To determine survival in afatinib-treated patients after treatment with first-generation EGFR tyrosine kinase inhibitors (TKIs) and to study resistance mechanisms in afatinib-resistant tumors. METHODS: Characteristics and survival of patients treated with afatinib after resistance to erlotinib or gefitinib in two large Dutch centers were collected. Whole exome sequencing (WES) and pathway analysis was performed on available pre- and post-afatinib tumor biopsies and normal tissue. RESULTS: A total of 38 patients were treated with afatinib. T790M mutations were identified in 22/29 (76%) pre-afatinib treatment tumor samples. No difference in median progression-free-survival (2.8 months (95% CI 2.3-3.3) and 2.7 months (95% CI 0.9-4.6), p = 0.55) and median overall-survival (8.8 months (95% CI 4.2-13.4) and 3.6 months (95% CI 2.3-5.0), p = 0.14) were observed in T790M+ patients compared to T790M- mutations. Somatic mutations in TP53, ADAMTS2, CNN2 and multiple genes in the Wnt and PI3K-AKT pathway were observed in post-afatinib tumors of six afatinib-responding and in one non-responding patient. No new EGFR mutations were found in the post-afatinib samples of the six responding patients. Further analyses of post-afatinib progressive tumors revealed 28 resistant specific mutations in six genes (HLA-DRB1, AQP7, FAM198A, SEC31A, CNTLN, and ESX1) in three afatinib responding patients. No known EGFR-TKI resistant-associated copy number gains were acquired in the post-afatinib samples. CONCLUSION: No differences in survival were observed in patients with EGFR-T790M treated with afatinib compared to those without T790M. Tumors from patients who had progressive disease during afatinib treatment were enriched for mutations in genes involved in Wnt and PI3K-AKT pathways.

Non-classic EGFR mutations in a cohort of Dutch EGFR-mutated NSCLC patients and outcomes following EGFR-TKI treatment.

BACKGROUND: Data on non-small-cell lung cancer (NSCLC) patients with non-classic epidermal growth factor receptor (EGFR) mutations are scarce, especially in non-Asian populations. The purpose of this study was to evaluate prevalence, clinical characteristics and outcome on EGFR-TKI treatment according to type of EGFR mutation in a Dutch cohort of NSCLC patients. METHODS: We retrospectively evaluated a cohort of 240 EGFR-mutated NSCLC patients. Data on demographics, clinical and tumour-related features, EGFR-TKI treatment and clinical outcome were collected and compared between patients with classic EGFR mutations, EGFR exon 20 insertions and other uncommon EGFR mutations. RESULTS: Classic EGFR mutations were detected in 186 patients (77.5%) and non-classic EGFR mutations in 54 patients (22.5%); 23 patients with an exon 20 insertion (9.6%) and 31 patients with an uncommon EGFR mutation (12.9%). Median progression-free survival (PFS) and overall survival (OS) on EGFR-TKI treatment were 2.9 and 9.7 months, respectively, for patients with an EGFR exon 20 insertion, and 6.4 and 20.2 months, respectively, for patients with an uncommon EGFR mutation. Patients with a double uncommon EGFR mutation that included G719X/L861Q/S768I had longer PFS and OS on EGFR-TKI treatment compared with patients with a single G719X/L861Q/S768I EGFR mutation (both P=0.02). CONCLUSIONS: In our Dutch cohort, prevalence and genotype distribution of non-classic EGFR mutations were in accordance with previously reported data. The PFS and OS on EGFR-TKI treatment in patients with an uncommon EGFR mutation were shorter compared with patients with classic EGFR mutations, but varied among different uncommon EGFR mutations.

Incidence of T790M mutation in (sequential) rebiopsies in EGFR-mutated NSCLC-patients.

AIM: Non-small cell lung cancer (NSCLC)-patients with an epidermal growth factor receptor (EGFR)-mutation have median progression-free survival (PFS) of 12 months on tyrosine kinase inhibitors (TKIs). Resistance is mediated by the EGFR T790M-mutation in the majority of patients. Longitudinal follow-up data are lacking. We retrospectively evaluated EGFR-mutated NSCLC-patients who were rebiopsied after TKI-treatment. A subgroup was sequentially rebiopsied along the course of the disease. PATIENTS AND METHODS: Advanced EGFR-mutated NSCLC-patients who had both a pre-TKI biopsy and post-TKI biopsy available were included. Information on treatments and (re)biopsies was collected chronologically. Primary endpoint was the incidence of the T790M-mutation. RESULTS: Sixty-six patients fulfilled the inclusion criteria. In first post-TKI biopsies, T790M-mutation was detected in 34 patients (52%) of patients. Twenty-seven patients had subsequent post-TKI rebiopsies with mutation analysis available; in 10 patients (37%) the T790M-status in subsequent post-TKI rebiopsies was not consistent with the T790M-status of the first post-TKI biopsy. Progression free survival (PFS) on TKI-treatment was 12.0 months. Objective response rate on TKI-treatment was 81%. Patients developing T790M-mutation at post-TKI biopsy had longer median PFS compared to T790M-negative patients (14.2 versus 11.1 months respectively (P=0.034)) and longer overall survival (45.9 months versus 29.8 months respectively (P=0.213)). Transformation to SCLC was detected in 1 patient (2%). CONCLUSION: Incidence of T790M-mutation at first post-TKI biopsy in this cohort of EGFR-mutated NSCLC-patients was 52%. Detection of T790M-mutation was not consistent over time; some patients who were T790M-positive at first post-TKI biopsy became T790M-negative in later post-TKI rebiopsies and vice versa. T790M-positive patients showed longer PFS than T790M-negative patients. Whether the low incidence of transformation to SCLC is justifying post-TKI rebiopsy in EGFR-mutated NSCLC-patients with acquired TKI-resistance in regular clinical practice is debatable.

High-dose, pulsatile erlotinib in two NSCLC patients with leptomeningeal metastases--one with a remarkable thoracic response as well.

A considerable number of patients with epidermal growth factor receptor (EGFR)-mutated non-small-cell lung cancer (NSCLC) develop leptomeningeal metastases. Leptomeningeal metastases are associated with deterioration of clinical symptoms and poor survival. Traditionally, treatment of metastases in the central nervous system consists of radiotherapy and less frequently, surgery. The role of systemic therapy is limited due to the blood-brain barrier inhibiting pharmacological doses to be reached in the central nervous system. Several case reports have described high-dose, pulsatile tyrosine kinase inhibitors as an effective treatment of leptomeningeal metastases, based on the hypothesis that higher concentrations in the cerebrospinal fluid can be reached by higher systemic concentrations. Here, we describe two patients with EGFR-mutated non-small cell lung cancer, with both clinical and radiological response to this high-dose, pulsatile regimen. Interestingly, one patient showed a remarkable response of intrathoracic response as well.

VeriStrat(®) has prognostic value in advanced stage NSCLC patients treated with erlotinib and sorafenib.

BACKGROUND: The serum proteomic test VeriStrat has been shown to be able to classify advanced non-small cell lung cancer (NSCLC) patients for overall survival (OS) after treatment with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). In this study, VeriStrat was evaluated as a pre-treatment stratification tool in patients with advanced stage NSCLC for treatment with the combination of erlotinib and sorafenib, considering both OS and progression-free survival (PFS) as end points. METHODS: Serum samples from 50 patients treated within the context of a phase II trial of first-line erlotinib and sorafenib were analysed with VeriStrat, a fully locked mass spectrometry-based test that identifies patients likely to have good or poor outcome on EGFR therapy based on eight distinct features in mass spectra. Analysis was performed fully blinded to all clinical data, and then the outcome data were analysed with respect to the obtained serum classifications. RESULTS: VeriStrat classified pre-treatment samples into two groups, VeriStrat Good and VeriStrat Poor, which were significantly different in OS (hazard ratio (HR) 0.30, log-rank P=0.009) and in PFS (HR 0.40, log-rank P=0.035). CONCLUSION: VeriStrat has shown its potential for stratification of unselected, advanced stage NSCLC patients treated in first line with a combination of erlotinib and sorafenib.

Routine follow-up intervals in patients with high-grade squamous intraepithelial lesions (HSIL) and free excision margins can safely be increased in the first two years after Large Loop Excision of the Transformation Zone (LLETZ).

OBJECTIVE: To assess the compliance of HSIL patients to the national Dutch routine follow-up protocol in the first 2 years after LLETZ and to determine if based on the status of excision margins, follow-up intervals could be modified. METHODS: A prospective cohort study was performed in patients, referred because of an abnormal Pap smear between 1996 and 2004 and treated for HSIL with LLETZ. The Dutch national routine follow-up protocol orders a Pap smear after 6, 12 and 24 months, respectively. Follow-up results were completed by using PALGA, the nationwide network and registry of histo- and cytopathology in the Netherlands. To assess compliance to the follow-up protocol, adequate follow-up was defined as three cervical smears taken after 6 (+/-3), 12 (+/-3) and 24 (+/-3) months, respectively. RESULTS: Compliance to the first 2 years follow-up protocol declined from 86.2% to 64.8% to 51.2% for first, second and third follow-up cervical smears, respectively. Patients with involved excision margins had a three times higher overall risk of developing a subsequent HSIL after LLETZ as compared to patients with free excision margins (HR: 3.2, 95% CI=1.3-7.9, p=0.01). Risk for diagnosing HSIL during the first 12 months of follow-up for patients with free excision margins was only 1%. CONCLUSIONS: Compliance to the Dutch national routine follow-up protocol in HSIL patients after LLETZ is only moderate. For HSIL patients with free excision margins after LLETZ the first cytological follow-up interval can safely be increased to 12 months.