Pancreatic ductal adenocarcinoma is a lethal cancer with a 5-year prognosis of less than 10%. In the past decade, researchers have focused on characterizing molecular subtypes to more accurately define prognosis and therapy. Two main molecular subtypes, basal-like and classical, have been described in various papers. Aside from that, it is also possible to characterize tumours based on their histological appearance.
In this study, we aimed to determine whether the molecular subtypes can be characterized by a histological phenotype or by specific markers. We based the histological appearance on a paper of Schlitter et al. and used samples of 81 patients from the molecular subtyping paper of Puleo et al. The HE slides of these patients were evaluated by multiple pathologists and categorized in a specific
histological subtype. The markers were tested using either immunohistochemistry or multiplex fluorescent RNAscope (in situ hybridization). These markers were tested on the same samples, and the stainings were scanned at high resolution. This was then quantified using the HALO software.
We found that certain histological appearances correlate with molecular subtypes. For the basal-like subtype, the molecular subtype with the worst prognosis, we found that these tumours showed a gyriform pattern, which is a less differentiated histology. For classical tumours, which have a better prognosis, tumours often showed either a classical appearance or a papillary appearance, both more differentiated histologies. We also found certain markers using the multiplex fluorescent RNAscope that were expressed more in the basal-like subtype compared to the classical subtype.
These findings could indicate that we can determine the molecular subtypes based on either the histological phenotype or using markers, which would be both time- and cost-efficient. However, these findings should be tested on a larger cohort of patients, and on samples that don’t belong to one sequencing experiment. Determining a subtype quickly could aid in the prognosis of a patient and to determine the therapy regimen more specifically.
Original languageEnglish
Publication statusPublished - 7 Feb 2020
EventBelgian Association for Cancer Research 2020: Cancer metastases: from bedside to bench - Vrije Universiteit Brussel, Jette, Belgium
Duration: 7 Feb 20207 Feb 2020
https://www.bacr.be/program/

Conference

ConferenceBelgian Association for Cancer Research 2020
Abbreviated titleBACR
CountryBelgium
CityJette
Period7/02/207/02/20
Internet address

ID: 51119317