Clinical usefulness of KRAS mutational analysis in the diagnosis of pancreatic adenocarcinoma by means of endosonography‐guided fine‐needle aspiration biopsy

Abstract

SUMMARYAim: To establish the usefulness of KRAS mutational analysis in the diagnosis of pancreatic adenocarcinoma by comparing this technique with conventional cytology in aspirates obtained by endosonography-guided fine-needle aspiration. Methods: All consecutive patients with pancreatic focal lesions undergoing endosonography-guided fine-needle aspiration were included. Samples were obtained with the concourse of an attendant cytopathologist. Detection of codon-12 KRAS mutations was performed by the restriction fragment length polymorphism-polymerase chain reaction method. The effectiveness of conventional cytology, KRAS mutational analysis and their combination was established with respect to the definitive diagnosis. A cost-effectiveness analysis was also performed.Results: Thirty-three patients had pancreatic adenocarcinoma and 24 patients had other lesions. A total of 136 samples was obtained. In patients in whom specimens were adequate (93% for cytology; 100% for mutational analysis), the specificity of both techniques was 100%, whereas the sensitivity favoured cytology (97% vs. 73%). When inadequate samples were considered as misdiagnosed, a combination of both techniques reached the highest overall accuracy (cytology, 91%; mutational analysis, 84%; combination of both, 98%). Conclusions: Cytology from aspirates obtained by endosonography-guided fine-needle aspiration is the most precise single technique for the diagnosis of pancreatic adenocarcinoma. However, when adequate specimens are not available to reach a cytological diagnosis, the addition of KRAS mutational analysis represents the best strategy.

Clinical impact of K-ras mutation analysis in EUS-guided FNA specimens from pancreatic masses

“…Several authors suggested that K-ras mutation analysis of EUS-FNA specimens is valuable. 16,[23][24][25][26][27][28] However, published reports have included relatively small numbers of patients with PDAC and other pancreatic tumors for comparison (Table 5). Here, we prospectively investigated the most patients in a single study to date and examined other pancreatic diseases for a differential diagnosis.…”

OncogèneKraset cancer du pancréas

“…La spécifi-cité est assez élevée (entre 90 et 100 %), ce qui permet d'assurer le diagnostic de bénignité des masses pancréatiques. Plusieurs études, incluant celle menée par notre équipe, ont évalué l'importance de la recherche de la mutation de Kras dans le matériel de cytoponction pancréatique pour le diagnostic d'adénocarcinome (Tableau II) [20,[23][24][25][26]. Cette analyse apporte, tout d'abord, une contribution au diagnostic différentiel entre cancer et pancréatite chronique pseudotumorale.…”

An evaluation of risk factors for inadequate cytology in EUS-guided FNA of pancreatic tumors and lymph nodes

“…Additionally, it has also been shown that the presence of an attending cytopathologist during the procedure is cost-effective; however, the availability of an onsite cytopathologist is a major issue. 12,13 The strategy used in our study, having an on-site cytotechnologist just to interpret adequacy, seems like an attractive approach. In institutions in which this is unavailable, an alternative may be to have an experienced endosonographer assess the cytological ade- Information was unavailable for the following variables: onsite pathology (n ϭ 23), number of biopsy specimens taken (n ϭ 1), needle gauge (n ϭ 2), and pathologist (n ϭ 1).…”