Needle-Tract Seeding of Pancreatic Cancer after EUS-FNA: A Systematic Review of Case Reports and Discussion of Management

SIMPLE SUMMARY: Needle-tract seeding (NTS) is a rare but serious complication of Endoscopic Ultrasound-guided biopsy of pancreatic adenocarcinoma. Due to its very low incidence, there is lack of evidence about its management. The aim of our systematic review is to deepen the knowledge about this entity and highlight therapeutic approaches. After a systematic search we retrieved 45 cases, plus one from our center. The majority of patients (87.1%) underwent surgical resection of the primary pancreatic tumor, of which only 55.9% received neoadjuvant and/or adjuvant chemotherapy. NTS occurred at a median of 19 months after primary diagnosis, with a secondary surgical approach in 82.4% of patients and a median overall survival of 26.5 months compared to 15.5 months when treated with chemo/radiotherapy. NTS is rare, generally occurs late and might be treated aggressively with good results. As only a low rate of patients developing NTS underwent (neo)adjuvant chemotherapy, one may speculate that it might be protective. ABSTRACT: Needle-tract seeding (NTS) has been sporadically reported as complication of Endoscopic Ultrasound (EUS)-guided aspiration (FNA) in pancreatic adenocarcinoma (PDAC). However, the evidence of its treatment and outcome is sparse. Adhering to PRISMA guidelines, we conducted a systematic review of EUS-FNA NTS cases of PDAC and analyzed their management and outcome. Up to September 2022, the search query retrieved forty-five cases plus an unpublished case from our center, for a total of forty-six; 43.6% were male, with a mean age of 68.6 years. Thirty-four patients (87.1%) underwent an initial surgical resection, with only 44.1% and 5.9% undergoing adjuvant and neoadjuvant chemotherapy, respectively, and 5.9% undergoing both. The NTS nodule was mostly located in the posterior gastric wall, developing at a median of 19 months after primary resection; 82.4% underwent surgical resection of the seeding, while for 17.6%, palliative chemotherapy treatment. Follow-up after NTS diagnosis and treatment was reported for only twenty-three patients: when NTS was treated with surgery, the median overall survival was 26.5 months compared to 15.5 if treated with radio/chemotherapy. NTS after EUS-FNA of PDAC occurs late and might be treated aggressively with good results. Interestingly, only a low number of patients developing NTS underwent chemotherapy for the primary cancer, suggesting its possible protective role.