Tissue imprint for molecular mapping of deep surgical margins in patients with head and neck squamous cell carcinoma

Abstract

Tissue imprinting can generate molecular marker maps of tumor cells at deep surgical margins. The purpose of this study was to evaluate the feasibility of this method for detection of residual head and neck squamous cell carcinoma (HNSCC). Paired fresh tissue and nitrocellulose membrane imprints of tumor and deep margins were collected from 17 HNSCC resections. DNA was amplified using quantitative methylation-specific polymerase chain reaction (qMSP) for p16, DCC, KIF1A, and EDNRB. Levels of methylation in tumors and deep margins were compared. DNA from imprints was adequate for qMSP. Hypermethylation of target genes was present in 12 of 17 tumors and in 8 deep margins. Methylation level was better from margin imprints than tissue. During follow-up (median, 13 months), local or regional recurrences occurred in 6 cases of which 5 had molecularly positive margins. Tissue imprinting is feasible for molecular detection of residual tumor at deep surgical margins and may correlate with locoregional recurrence.