Human pancreatic cancer fusion 2 (HPC2) 1-B3: a novel monoclonal antibody to screen for pancreatic ductal dysplasia

Reliable Detection of Somatic Mutations for Pancreatic Cancer in Endoscopic Ultrasonography-Guided Fine Needle Aspirates with Next-Generation Sequencing: Implications from a Prospective Cohort Study

BACKGROUND OR PURPOSE

Pancreatic ductal adenocarcinoma (PDAC) is commonly diagnosed by endoscopic ultrasound-guided fine needle aspiration (EUS-FNA). However, the diagnostic adequacy of EUS-FNA is often limited by low cellularity leading to inconclusive results. We aimed to investigate the feasibility and added utility of targeted next-generation sequencing (NGS) on PDAC EUS-FNAs.

METHODS

EUS-FNAs were prospectively performed on 59 patients with suspected PDAC (2014-2017) at a high-volume center. FNAs were analyzed for the presence of somatic mutations using NGS to supplement cytopathologic evaluations and were compared to surgical specimens and circulating tumor DNA (ctDNA).

RESULTS

Fifty-nine patients with suspected PDAC were evaluated, and 52 were diagnosed with PDAC on EUS-FNA. Four of the remaining seven patients had inconclusive EUS-FNAs and were ultimately diagnosed with PDAC after surgical resection. Of these 56 cases of PDAC, 48 (85.7%) and 18 (32.1%) harbored a KRAS and/or TP53 mutation on FNA NGS, respectively. Particularly, in the four inconclusive FNA PDAC diagnoses (false negatives), half harbored KRAS mutations on FNA. No KRAS/TP53 mutation was found in remaining three non-PDAC cases. All EUS-FNA detected KRAS mutations were detected in 16 patients that underwent primary tumor NGS (100% concordance), while 75% KRAS concordance was found between FNA and ctDNA NGS.

CONCLUSION

Targeted NGS can reliably detect KRAS mutations from EUS-FNA samples and exhibits high KRAS mutational concordance with primary tumor and ctDNA. This suggests targeted NGS of EUS-FNA samples may enable preoperative ctDNA prognostication using digital droplet PCR and supplement diagnoses in patients with inconclusive EUS-FNA.

RNA sequencing distinguishes benign from malignant pancreatic lesions sampled by EUS-guided FNA

BACKGROUND AND AIMS

EUS-guided FNA (EUS-FNA) is the primary method used to obtain pancreatic tissue for preoperative diagnosis. Accumulating evidence suggests diagnostic and prognostic information may be obtained by gene-expression profiling of these biopsy specimens. RNA sequencing (RNAseq) is a newer method of gene-expression profiling, but published data are scant on the use of this method on pancreas tissue obtained via EUS-FNA. The aim of this study was to determine whether RNAseq of EUS-FNA biopsy samples of undiagnosed pancreatic masses can reliably discriminate between benign and malignant tissue.

METHODS

In this prospective study, consenting adults presented to 2 tertiary care hospitals for EUS of suspected pancreatic mass. Tissue was submitted for RNAseq. The results were compared with cytologic diagnosis, surgical pathology diagnosis, or benign clinical follow-up of at least 1 year.

RESULTS

Forty-eight patients with solid pancreatic mass lesions were enrolled. Nine samples were excluded because of inadequate RNA and 3 because of final pathologic diagnosis of neuroendocrine tumor. Data from the first 13 patients were used to construct a linear classifier, and this was tested on the final 23 patients (15 malignant and 8 benign lesions). RNAseq of EUS-FNA biopsy samples distinguishes ductal adenocarcinoma from benign pancreatic solid masses with a sensitivity of .87 (range, .58-.98) and specificity of .75 (range, .35-.96).

CONCLUSIONS

This proof-of-principle study suggests RNAseq of EUS-FNA samples can reliably detect adenocarcinoma and may provide a new method to evaluate more diagnostically challenging pancreatic lesions.