Article Text
Abstract
Introduction Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) of pancreatic lesions is a valuable tool in the investigation of suspected pancreatic cancer. Recent international studies on the diagnostic utility of this technique have reported sensitivity and accuracy levels of >90%. There is a paucity of UK centre data on diagnostic performance. In this retrospective observational study we aim to report the largest UK cohort and provide comparison with international standards.
Methods Hammersmith Hospital is a regional pancreatobiliary referral centre. A single experienced endosonographer provides all diagnostic and therapeutic EUS services. A retrospective analysis of patients who underwent EUS-FNA for solid pancreatic lesions between Jan 2006 and Oct 2009 was performed. Cytopathology reports for cases were scrutinised. Cytological diagnosis was compared with the reference standard of surgical or biopsy histology, clinical and radiological evidence of disease progression, or in the case of benign cytology a minimum of 6 months clinical follow-up.
Results A total of 113 EUS-FNAs for a solid pancreatic lesion were identified during the study period (average age 66 years, M/F ratio 1.1:1). The final outcomes were: pancreatic carcinoma (87/113, 77%), benign disease or pancreatitis (18/113, 16%) neuroendocrine tumour (5/113, 4%), metastasis (2/113, 1.7%), lymphoma (1/113, 0.8%).
15/113 cytology specimens were graded as “C4” or “highly suspicious of adenocarcinoma”, and in all the final diagnosis was pancreatic adenocarcinoma (PPV 100%). Performance characteristics were calculated both considering the C4/suspicious specimens as false negatives for malignancy and true positives (Abstract 081).
Comparing the performance of EUS-guided FNA in years 2006–2007 to years 2008–2009 there was an improvement in sensitivity (78% to 92%) and accuracy (82% to 93%), respectively.
Conclusion In solid pancreatic lesions FNA specimens classified cytologically as C4 have a 100% PPV for adenocarcinoma and should be considered diagnostic for this. The performance of EUS-FNA of solid pancreatic lesions in our institution, a UK regional referral centre, is comparable to international standards. A recent improvement in sensitivities and accuracy to in excess of 90% was noted. Further endosonographer experience, better case selection and routine use of “in-room” cytopathologist support may account for this and should be considered as strategies to improve accuracy further.