Proportion of unresectable pancreatic cancer specimens obtained by endoscopic ultrasound-guided tissue acquisition meeting the OncoGuide™ NCC Oncopanel System analysis suitability criteria: a single-arm, phase II clinical trial

Background: There are limited studies on the results of comprehensive genomic profiling testing for pancreatic cancer tissue specimens by endoscopic ultrasound-guided tissue acquisition (EUS-TA). This study aimed to evaluate the proportion of specimens obtained by EUS-TA using a 19-gauge (G) fine-needle biopsy (FNB) needle for unresectable pancreatic cancer (UR-PC) that met the OncoGuide^™ NCC Oncopanel System (NOP) analysis suitability criteria. Methods: In this single-arm, prospective, phase II study, EUS-TA was performed using a 19G FNB biopsy needle in patients with suspected UR-PC based on a contrast-enhanced computed tomography scan. The primary endpoint was the proportion of patients who met the NOP analysis suitability criteria, with a threshold, expected value, α-error, and power of 40%, 70%, 0.025, and 0.9, respectively, and the planned number of enrolled patients was 33. The NOP analysis suitability criteria were defined as tumor cell content ≥ 20% and tissue size ≥ 4 mm². Results: Thirty-three patients were enrolled. The procedural success rate was 100%, and the cytodiagnosis of class V was observed in all patients. The proportion of patients meeting the NOP analysis suitability criteria was 63.6% (95% CI 47.22–80.05), which satisfied the predefined criteria to be considered valid. Adverse events occurred in 9.0% of the patients. Conclusions: The proportion of patients with UR-PC who met the NOP analysis suitability criteria for EUS-TA using a 19G FNB needle was effective for achieving the primary endpoint, making it a valid test method. Adverse events occurred at a higher rate than that previously reported.