1612P - Fine needle biopsies are feasible as a minimally invasive means for targeted next generation sequencing in advanced solid tumors

Date 28 September 2014
Event ESMO 2014
Session Poster Display session
Topics Translational Research
Presenter Aaron Hansen
Citation Annals of Oncology (2014) 25 (suppl_4): iv546-iv563. 10.1093/annonc/mdu358
Authors A. Hansen1, W. Geddie2, S. Boerner2, S. Ghai3, H. Berman2, S. Serra2, M. Roehrl2, A.M. Joshua4, A.M. Oza5, M. Moore6, E. Amir7, T. Usmani6, A. Giesler6, N. Amin8, T. Zhang9, M. Sukhai9, T. Stockley9, S. Kamel-Reid9, L. Siu10, P. Bedard6
  • 1Department Of Medicine, University Health Network, M5G 2M9 - Toronto/CA
  • 2Laboratory Medicine Program, University Health Network, Toronto/CA
  • 3Joint Department Of Medical Imaging, University Health Network, Toronto/CA
  • 4Medical Oncology, Princess Margaret Hospital, Toronto/CA
  • 5Dept. Of Medical Oncology And Hematology, Princess Margaret Hospital, M5G 2M9 - Toronto/CA
  • 6Department Of Medical Oncology And Hematology, Princess Margaret Cancer Centre, Toronto/CA
  • 7Dmoh, Princess Margaret Cancer Centre, UHN, M5G 2M9 - Toronto/CA
  • 8Biospecimen Sciences Program, University Health Network, Toronto/CA
  • 9Advanced Molecular Diagnostics Laboratory, Princess Margaret Cancer Centre, Toronto/CA
  • 10Dept Of Medical Oncology, Princess Margaret Hospital, CA-M5G 2M9 - Toronto/CA

Abstract

Aim

Core needle biopsies (CNB) are used routinely to obtain metastatic tumor tissue for genotyping and to aid clinical decision-making. Fine needle biopsies (FNB) are a less invasive method to procure tumor cells. This ongoing study aims to compare the success and concordance of clinical genotyping using CNB and FNB of the same metastasis.

Methods

Patients (pts) with advanced melanoma, breast, colorectal and gynecological cancers with no contraindication to biopsy were eligible. FNB were performed first (≤3 passes) followed by 3 CNB, using 25 and 18 gauge needles respectively. FNB underwent rapid onsite evaluation to ensure lesion sampling and both rinse and smear were used for profiling. CNB were formalin fixed and paraffin embedded. Following pathology review, tumor DNA was extracted and profiling was performed in a CLIA-certified laboratory using the Illumina MiSeq TruSeq panel (48 genes, 212 amplicons) or a customized solid tumor genotyping panel on the Sequenom MassArray (23 genes, 279 mutations). If available, genomic concordance between the archival specimen of the primary tumor and metastasis was assessed.

Results

35 pts (21 breast, 5 gynecological, 5 colorectal and 4 melanoma) were enrolled. 31 pts underwent a single biopsy, 3 pts were considered unsuitable and 1 pt had 2 biopsies separated by a line of systemic therapy. Liver was the most common biopsy site (15 pts [48%]). No biopsy related severe adverse events occurred. 26 biopsies have been reported, 5 CNB-FNB pairs had no tumor and another 4 CNB had no tumor with malignant cells seen on FNB only. There was no difference in DNA yield from CNB and FNB (mean 660ng vs 900ng, p=0.24). 29 mutations in 12 genes were identified from 22 biopsies (TP53 9, PIK3CA 5, APC 3, BRAF 2, ERBB2 2, KRAS 2, AKT1 1, ATM 1, CTNNB1 1, JAK2 1, KIT 1, NRAS 1). Two of the 20 pts with available primary tissue showed discordance with the biopsy of the metastasis (involving ATM and TP53 variants).

Conclusions

Genotyping or targeted sequencing of FNB is feasible. CNB and FNB show high concordance for genotype. Few genotype differences were detected between the primary tumor and metastasis, although broader genomic testing may be required to identify clonal evolution.

Disclosure

L.L. Siu: Research funding: Roche, Pfizer, Bristol-Myer Squibb, Boerhinger-Ingelheim. All other authors have declared no conflicts of interest.