Response to HER2 Inhibition in a Patient With Brain Metastasis With EGFR TKI Acquired Resistance and an HER2 Amplification

A 62-year-old man was referred to our university hospital for treatment of advanced adenocarcinoma of the lung after disease progression on two lines of EGFR TKI and one line of chemotherapy. Fluorescent in situ hybridization analysis upon progression showed an HER2 amplification. At our weekly Molecular Tumor Board (MTB), a decision was made to treat this patient with afatinib, which resulted in a partial response. However, progression was observed with a facial nerve paresis due to a metastasis in the skull. A biopsy of a location in the thorax revealed the presence of an EGFR-T790M mutation associated with acquired resistance, after which treatment with osimertinib was started. After 6 months, disease progression was observed, and a new biopsy was taken from the pelvic bone, which revealed the original amplification of HER2 together with the EGFR-L858R mutation, the EGFR-T790M mutation was not detected. The MTB decided to treat the patient with trastuzumab/paclitaxel. A partial response was observed in different bone lesions, while the skull metastasis with ingrowth in the brain remained stable for 6 months. Because of progression of the bone metastases after 6 months, a biopsy of a lesion in the thorax wall was taken. In this lesion, the EGFR-T790M mutation could be detected again. The MTB advised to start treatment with a combination of osimertinib and afatinib. This resulted in an impressive clinical improvement and a partial response of the bone metastases on the most recent 18-fluorodeoxyglucose positron emission tomography and computer tomography-scan. In conclusion, adjusting treatment to the mutational make-up of the tumor is a great challenge. For optimal treatment response multiple biopsies and re-biopsy upon progression are imperative. As more genes are investigated, treatment decision becomes increasingly difficult, therefore, expert opinions from an MTB is essential.

Abstract 754: Treatment decision-making of rare ERBB2 (HER2) mutations in lung cancer; a role for multidisciplinary molecular tumor boards

Introduction:

Breakthroughs in cancer research have resulted in mutation-specific targeted therapies (precision medicine). Most of these new drugs are only effective in patients with an actionable molecular profile. Thus, predictive molecular testing enables oncologists to select individual patients for the most appropriate (targeted) therapy and to reduce the burden of overtreatment. The number of clinically relevant predictive markers that are routinely analyzed is growing rapidly, resulting in the identification of rare mutations, mutations with unknown relevance and coexistence of two or more mutations in the same sample. Incorporating these into the optimal treatment for the individual patient can be complex.

Methods: A total of 2461 sequential tumor biopsies were analyzed at our institute using targeted next generation sequencing (Ion Torrent platform). 230 of these patients were discussed at a weekly Molecular Tumor Board (MTB) meeting. Cases involved 170 lung and 21 colorectal carcinomas, 24 melanomas, 1 GIST and a range of other malignancies with uncommon and rare mutations. The board is composed of pulmonologists, medical oncologists, pathologists and clinical scientists in molecular pathology. The goal of the MTB is to discuss the biological and clinical relevance of rare mutations or uncommon profiles and to suggest treatment options based on registered, off-label or trial-based drugs presently available in the Netherlands.

Results: In this abstract we report on four patients with an ERBB2 exon 20 mutation and 1 patient with ERBB2 amplification received anti-HER2 treatment after an MTB consensus decision. Two patients with an insertion in exon 20 of ERBB2: (c.2313_2324dup; p.(Y772_A775dup)) received first line therapy with afatinib and showed a partial response and stable disease respectively. One patient with a c.2524G>A; p.(V842I) mutation received afatinib and showed stable disease for 3 months. A patient with another ERBB2 exon 20 insertion (c.2326_2327insTAT:p.(G776delinsVC)) received afatinib but had progressive disease within two months. One patient with an ERBB2 amplification by FISH and high (3+) HER2(ERBB2) expression, showed a partial response to trastuzumab. All patients had stage IV and would without genomic knowledge been treated with chemotherapy.

Conclusion: Lung cancer patients with sporadic ERBB2 mutations might benefit from targeted ERBB2 therapy. For an optimal treatment decision, patients with rare mutations in general, may benefit from discussion in a multidisciplinary molecular tumor board. In the future, both the considerations for targeted therapy as well as treatment response and toxicity should be registered in an open-access database and shared with other national and international Molecular Tumor Board initiatives to allow comparison with traditional treatments.

Citation Format: Arja ter Elst, Nils A. 't Hart, Anthonie J. van der Wekken, Wim Timens, Lucie B. Hijmering-Kappelle, Geke A. Hospers, Hilde Jalving, Elise M. van der Logt, Leon C. van Kempen, Sjoukje F. Oosting, Matthew R. Groves, T Jeroen Hiltermann, Anke van den Berg, Harry J. Groen, Ed Schuuring. Treatment decision-making of rare ERBB2 (HER2) mutations in lung cancer; a role for multidisciplinary molecular tumor boards [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 754. doi:10.1158/1538-7445.AM2017-754

Abstract 2718: Molecular Tumor Board treatment predictions on rare EGFR exon 20 mutations

Purpose:

To evaluate treatment response following the Multidisciplinary Molecular Tumor Board (MTB) decisions which focused on EGFR exon 20 mutations in lung adenocarcinoma.

Methods:

Molecular studies were routinely performed using the Ion Torrent sequencing platform for histologically or cytologically diagnosed lung adenocarcinoma. Since October 2014 patients with rare (prevalence <1%) or combinations of rare mutations were discussed at the MTB of the University Medical Center Groningen. More common, known sensitive EGFR, BRAF V600E, as well as KRAS, and PIK3CA mutations were excluded. To predict the best therapy for a subset of patients with EGFR exon 20 insertion mutations the literature is reviewed and molecular models were built using SWISS-MODEL, is used to predict protein tertiary structure (https://swissmodel.expasy.org/interactive/wcurbt/models/).

Summary of data:

Over a period of 2 years 1389 samples were tested. A total of 170 (12.2%) rare mutations were detected in lung cancer. Among these rare mutations we observed 16 EGFR exon 20 insertions and other mutations like e.g: p.T790M, p.D761N, p.D770delinsGY, p.S768_D770dup, p.V769_D770insSFL, p.N771_H773dup, p.T790S. Using an in silico modeling of protein responses with TKI were predicted to be likely in EGFR T790M mutations and p.S768_V769delinsIL, but not in p. D770delinsGY, p.S768_D770dup, p.V769_D770insSFL, and p.N771_H773dup mutations. Eight patients with an exon 20 mutation were treated with an EGFR TKI. One patient (p.D761N) had a partial response on erlotinib 300mg daily. On afatinib monotherapy 2 out of 3 pts had stable disease (PFS 3-11 months). On afatinib/cetuximab treatment 1 out of 2 pts (p.D770delinsGY) had a partial response and the other patient had stable disease (p.S768_D770dup) (PFS 11 and 4 months, resp.). Two evaluable patients were treated with osimertinib: the first patient initially progressed on afatinib (p.V769_D770insSFL). The protein model predicted no response, since we predicted hindrance of osimertinib. The model predicted no response on osimertinib in the second patient as well, and during treatment a stable disease for 4 months was observed (p.N771_H773dup).

This molecular information from the weekly MTB meeting was delivered within 2 weeks to the treating physician. Feedback on treatment outcome helped to further improve treatment predictions.

Conclusion:

The Molecular Tumor Board is an effective multidisciplinary team to discuss rare mutations. Our pilot data show that the evaluation of the use and effectiveness of a theoretical model concerning protein structures is not possible yet, however, did provide a clear insight in protein structures in a mutated EGFR receptor supporting decision making of treatment options.

Citation Format: Anthonie J. van der Wekken, Matthew R. Groves, Arja ter Elst, Nils A. 't Hart, Lucie B. Hijmering-Kappelle, Thijo J. Hiltermann, Anke van den Berg, Wim Timens, Ed Schuuring, Harry J. Groen. Molecular Tumor Board treatment predictions on rare EGFR exon 20 mutations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2718. doi:10.1158/1538-7445.AM2017-2718

CT-guided percutaneous hookwire localization increases the efficacy and safety of VATS for pulmonary nodules

BACKGROUND AND OBJECTIVES

The diagnosis of pulmonary nodules of unknown origin is challenging, and such nodules are not always suitable for transthoracic needle biopsy. With the advent of video assisted thoracic surgery (VATS) and CT-guided percutaneous hookwire localization (CT-PHL) we hypothesized that the combination of these two procedures will improve early diagnosis.

METHODS

Selection criteria were a nodule not well approachable with fine needle biopsy and the therapeutic consequences of a diagnosis as assessed by the multidisciplinary oncology board. Efficacy and safety of the combination of CT-PHL prior to VATS was studied in terms of, histological diagnosis, complete resection rate, complications, conversion rate to thoracotomy, and duration of procedures.

RESULTS

A total of 150 pulmonary nodules were located and resected in 150 patients. The median nodule diameter was 9 mm (range 4-24) and located within 30 mm of the pleural surface (median 7, range 0-29). The resection was complete in 96%, and in 100% a definitive histological diagnosis was obtained. Complications requiring intervention during the CT-procedure occurred in 11 patients (7.3%). Complications of VATS consisted of major complications (2.0%) and minor complications (4.0%). The 30 Day mortality was 1.4% and in hospital mortality 0.7%. Conversion to thoracotomy occurred in 4.7% patients. Median CT-localization time was 25 min (range 5-72), median VATS time was 49 min (range 14-169).

CONCLUSIONS

CT-PHL is a very efficient and safe procedure prior to VATS for pulmonary nodules and allows in 96% radical resection with a diagnostic accuracy of 100%.

Genomic Aberrations in Crizotinib Resistant Lung Adenocarcinoma Samples Identified by Transcriptome Sequencing

ALK-break positive non-small cell lung cancer (NSCLC) patients initially respond to crizotinib, but resistance occurs inevitably. In this study we aimed to identify fusion genes in crizotinib resistant tumor samples. Re-biopsies of three patients were subjected to paired-end RNA sequencing to identify fusion genes using deFuse and EricScript. The IGV browser was used to determine presence of known resistance-associated mutations. Sanger sequencing was used to validate fusion genes and digital droplet PCR to validate mutations. ALK fusion genes were detected in all three patients with EML4 being the fusion partner. One patient had no additional fusion genes. Another patient had one additional fusion gene, but without a predicted open reading frame (ORF). The third patient had three additional fusion genes, of which two were derived from the same chromosomal region as the EML4-ALK. A predicted ORF was identified only in the CLIP4-VSNL1 fusion product. The fusion genes validated in the post-treatment sample were also present in the biopsy before crizotinib. ALK mutations (p.C1156Y and p.G1269A) detected in the re-biopsies of two patients, were not detected in pre-treatment biopsies. In conclusion, fusion genes identified in our study are unlikely to be involved in crizotinib resistance based on presence in pre-treatment biopsies. The detection of ALK mutations in post-treatment tumor samples of two patients underlines their role in crizotinib resistance.

Chronic Obstructive Pulmonary Disease Is Not Associated with KRAS Mutations in Non-Small Cell Lung Cancer

Mutations in epithelial growth factor receptor (EGFR), as well as in the EGFR downstream target KRAS are frequently observed in non-small cell lung cancer (NSCLC). Chronic obstructive pulmonary disease (COPD), an independent risk factor for developing NSCLC, is associated with an increased activation of EGFR. In this study we determined presence of EGFR and KRAS hotspot mutations in 325 consecutive NSCLC patients subjected to EGFR and KRAS mutation analysis in the diagnostic setting and for whom the pulmonary function has been determined at time of NSCLC diagnosis. Information about age at diagnosis, sex, smoking status, forced vital capacity (FVC) and forced expiratory volume in 1 sec (FEV₁) was collected. Chronic obstructive pulmonary disease(COPD) was defined according to 2013 GOLD criteria. Chi-Square, student t-test and multivariate logistic regression were used to analyze the data. A total of 325 NSCLC patients were included, 193 with COPD and 132 without COPD. COPD was not associated with presence of KRAS hotspot mutations, while EGFR mutations were significantly higher in non-COPD NSCLC patients. Both female gender (HR 2.61; 95% CI: 1.56–4.39; p<0.001) and smoking (HR 4.10; 95% CI: 1.14–14.79; p = 0.03) were associated with KRAS mutational status. In contrast, only smoking (HR 0.11; 95% CI: 0.04–0.32; p<0.001) was inversely associated with EGFR mutational status. Smoking related G>T and G>C transversions were significantly more frequent in females (86.2%) than in males (61.5%) (p = 0.008). The exon 19del mutation was more frequent in non-smokers (90%) compared to current or past smokers (36.8%). In conclusion, KRAS mutations are more common in females and smokers, but are not associated with COPD-status in NSCLC patients. EGFR mutations are more common in non-smoking NSCLC patients.

Abstract 4244: Comparison of different ALK tests in non-small cell lung cancer (NSCLC) patients treated with crizotinib and their clinical outcome

Background:

The screening algorithm for detection of ALK-rearranged NSCLC is still under investigation. The Break-Apart ALK FISH is the standard diagnostic test for the treatment with crizotinib. However, immunohistochemistry (IHC) with different antibodies shows excellent results when compared to ALK FISH. The efficacy of crizotinib is studied in relation to ALK FISH. We compared IHC outcome and the number of ALK breaks estimated with FISH with clinical outcome.

Methods:

Patients treated with crizotinib who had biopsies with sufficient tumor tissue were selected. Tumour response was assessed by CT using RECIST. Fluorescence in situ hybridization (FISH) was performed with Vysis LSI ALK Break Apart FISH Probe KIT (Abbott Molecular) and immunohistochemistry with Ventana ALK IHC Kit using D5F3 antibody.

Results:

Twenty one patients with NSCLC were selected, median (range) age 54 yrs (21-75); 19 had adenocarcinoma, 2 had large-cell carcinoma. We confirmed the presence of EML4-ALK fusions in all samples either by FISH or IHC. Median percentage of ALK breaks was 47% (6-76). Tumour response occurred in 12 pts having a median of 51 (6-76) breaks and 9 non-responders having a median of 27 (15-64) breaks. Of the 12 responders, 8 pts had positive IHC (67%), 3 were negative and 1 was not done; the FISH negative, IHC positive patient was one of the responders. Of the 9 non-responders 2 had positive IHC (22%), 3 negative (33%), and 1 was equivocal and 3 not done. Median PFS for positive IHC is 7.9 mo (95% CI., 5.5 - 10.3) and for negative IHC 1.6 mo (1.3 - 1.8), n = 17, p&lt;0.0001. OS survival data are 6.5 mo (95% CI., 0 - 17.8) and 18.3 mo (95% CI., 11.1 - 25.6) respectively, n = 17 p = 0.052.

PFS above 30% number of breaks was 7.0 mo (95% CI., 1.8 - 12.2) versus PFS below is 1.8 mo (95% CI., 0.7 - 2.9), n = 21, p = 0.05. OS survival data are 4.1 mo (95% CI., 0 - 9.3) and 16.1 mo (95% CI., 9.0 - 23.2) respectively, n = 21 p = 0.003. Therefore PFS and OS is more prolonged in those tumors who have ALK breaks above 30%. IHC difference are only significant for PFS.

Conclusions:

Both ALK FISH and IHC identify NSCLC patients who benefit from crizotinib treatment. Patients with ALK breaks above 30% have a better PFS and OS. IHC only differentiates for PFS.

Citation Format: Anthonie J. van der Wekken, Thijo JN Hiltermann, Wim Timens, Ed Schuuring, Harry JM Groen. Comparison of different ALK tests in non-small cell lung cancer (NSCLC) patients treated with crizotinib and their clinical outcome. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4244. doi:10.1158/1538-7445.AM2015-4244

The value of proteomics in lung cancer

Many studies have identified the prognostic and predictive value of proteins or peptides in lung cancer but most failed to provide strong evidence for their clinical applicability. The strongest predictive proteins seem to be fatty acid-binding protein heart (H-FABP), and the 8-peak mass spectrography signature of VeriStrat. When focusing on VeriStrat, a 'VeriStrat good' profile did not discriminate between chemotherapy and erlotinib. The 'VeriStrat poor' profile showed a better outcome to chemotherapy than to erlotinib. VeriStrat is a prognostic test and only the "poor profile" discriminates for the type of therapy that should be chosen. Whether it adds useful information in patients with advanced non-small cell lung cancer (NSCLC) and wild type EGFR mutations is still doubtful. The position of the VeriStrat test in clinical practice is still not clear and we are waiting for prospective studies where biomarker test are involved in clinical decision.

Abstract 3526: Pre-treatment EGFR mutation analysis predicts clinical outcome in a retrospective analysis of 24 non-squamous non-small-cell lung cancer (NSCLC) patients treated with second line afatinib

Purpose

Stage IV EGFR mutation positive NSCLC patients treated with reversible tyrosine kinase inhibitors(TKI) (i.e., erlotinib (E) or gefitinib (G)) develop resistance after 6-12 months, in half of the patients mediated by the T790M gatekeeper mutation. Afatinib (BIBW2992, Boehringer Ingelheim) has shown in a phase III study to prolong progression free survival (PFS) in patients progressing on EGFR TKI. The EGFR mutational pattern underlying these responses to afatinib is unknown. The current study was set out to evaluate response rate to afatinib in relation to tumor EGFR genotype.

Material/Methods

Patients with activating EGFR mutations, or without known EGFR mutations meeting Jackman criteria, progressing on E/G, and who had a re-biopsy before afatinib treatment were included. Mutations in exons 18-21 of the EGFR-gene were tested using high-resolution melting with reflex Sanger sequencing in both centers. We retrospectively studied EGFR mutations, PFS, and overall survival after treatment with afatinib. Statistical analysis was performed using Kaplan-Meier and Chi-square test.

Results

Initially 21/24 (88%) patients had stage IV NSCLC with a mean performance score of 1 (range 0-2). Before afatinib treatment 17/24 (71%) of patients received a platinum doublet. All patients received E or G. Three patients received both TKI sequentially. Four patients without mutation were treated for more than 6 months with E/G resulting in stable disease. PFS on previous E/G was 16 months (range, 2.0 - 37.9). At rebiopsy, 12/24 (50%) patients had a T790M mutation, no other secondary mutations were detected. There was no difference in duration of E/G administration neither in occurrence of T790M mutation (median 12.4 months (range, 6.8-34.4) with T790M vs. 19.2 months (range, 2.0-37.9) without T790M at rebiopsy; p=0.22). After PD on E/G, patients received afatinib mostly as 2nd or 3rd line therapy.Tumor response rate on afatinib was 12.5% (n=3). Of these, 1 had a T790M mutation. Disease control rate was 71%, median PFS was 3,0 months (range, 1.2-18.7 months). Median OS was 6.8 months (range, 1.3-19.0 months). The presence of T790M mutation did not influence PFS (with T790M, 2.9 vs without T790M, 3.2 months; p=0.684). However, it did influence OS (7.2 months vs. 3.5 months; p=0,039).

Conclusion

In our cohort of patients, PFS on afatinib was similar to the Lux-lung 1 study and similar for patients with or without T790M mutations. Duration of first generation TKI administration did not influence occurrence of T790M mutation. T790M mutation was in favor of a longer OS on afatinib.

Citation Format: Anthonie J. van der Wekken, Justine L. Kuiper, Daniëlle A.m. Heideman, Ed Schuuring, Wim Timens, Erik Thunnissen, Harry J.M. Groen, Egbert F. Smit. Pre-treatment EGFR mutation analysis predicts clinical outcome in a retrospective analysis of 24 non-squamous non-small-cell lung cancer (NSCLC) patients treated with second line afatinib. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3526. doi:10.1158/1538-7445.AM2013-3526