Ziel/Aim Intrahepatic cholangiocarcinoma (IHC) is a rare disease at increasing incidence.
Surgery is the only potentially curative treatment, but tumor aggressiveness leads
to frequent recurrences. The present study aims to elucidate if pre-operative textural
features of IHC on 18F-FDG PET may lead to non-invasive biological characterization of IHC and prediction
of survival outcome.
Methodik/Methods Our institutional database was searched to identify histologically-proven IHC patients
with pre-operative 18F-FDG PET/CT imaging.
On PET images, a manual slice-by-slice segmentation of IHC was performed and textural
features were extracted by LifeX® software. The association between textural features
and pathological data of IHC and overall/progression-free survival (OS/PFS) were investigated.
Ergebnisse/Results 80 patients (46 females, mean age 67 years, range 40-88) were included.
Poorly differentiated (G3) IHC had higher entropy (1.22 ± 0.22 vs. 1.11 ± 0.28 of
G1-2 ICH, P = 0.076) and lower uniformity (0.07 ± 0.04 vs. 0.11 ± 0.07, P = 0.033).
Tumors with vascular invasion had higher SUVmean, Entropy, GCLM_Correlation, GLRLM_HGRE (p < 0.05) and lower SHAPE_Sphericity and
NGLDM_Coarseness (p < 0.01). Patients with lymph node metastases had higher IHC Entropy
(P = 0.023), GLCM_Entropy (p < 0.01), and SUVmean (p < 0.05). After a median follow-up of 22 months, 3-year OS and PFS were 48.8% and
24.7%. A higher Entropy predicted a lower 3-years OS (68.9% if Entropy ≤1.16 vs. 31.6%,
if >1.16, HR = 2.18, P = 0.02) and PFS (32.2 vs 17.8%, respectively, HR = 1.73, P = 0.039).
A higher Uniformity predicted a better OS (32.5% if Uniformity <0.078 vs 67.1% if
≥0.078, HR = 0.5, P = 0.038) and PFS (18.2 vs 31.4%, HR = 0.61, P = 0.059). At multivariate
analysis, Entropy and Uniformity were independent OS predictors (P = 0.011 and P = 0.037),
together with age and N-status.
Schlussfolgerungen/Conclusions FDG-PET radiomic indices of IHC are relevant biomarkers that can non-invasively predict
pathological data of tumors and survival outcome.