European Radiology: This MR sign indicates the possibility of IPMN combined with invasive pancreatic cancer

Intra-ductal papillary myxoma (IPMN) is characterized by the dilation of the main pancreatic duct or branch due to papillary hyperplasia of epithelial cells and the production of abundant mucus
.
Studies have shown that IPMN is a precursor to the development of pancreatic ductal adenocarcinoma (PDAC) caused by papillary hyperplasia of epithelial cells.

There are two types of pancreatic cancer associated with IPMN, one in which IPMN itself becomes malignant (IPMN with invasive carcinoma) and the other occurs in areas far away from IPMN (IPMN with invasive carcinoma: IPMN-IC).

It is often clinically difficult to distinguish between IPMN and IPMN-IC with invasive carcinoma, and the etiology and risk factors of IPMN-IC are not well understood.

Recent reports suggest that pancreatic fat infiltration is a risk factor
for PDAC.
Pancreatic fat infiltration induces chronic inflammation caused by the release of various cytokines and chemokines from adipose tissue, leading to pancreatic cancer
.

Recently, a study published in the journal European Radiology used 3T MRI to explore quantitative magnetic resonance imaging (MRI) indicators related to IPMN-IC, which provides an imaging reference for the early identification and treatment of pancreatic cancer
.

A total of 132 patients were included in the performance, each of whom underwent a 3-T MRI scan
of the abdomen.
In normal pancreatic parenchymal measurements, the pancreas-to-muscle signal-intensity ratio (SIR-I) in the inverting image, the SIR (SIR-T2) in the inverting image, the SIR (SIR-T2) in the T2-weighted image, and the ADC (×10) in the DWI were calculated ^-3mm²/s) and proton density fat fraction (PDFF [%])
in multi-echo 3D DIXON.
Patients were divided into three groups (normal pancreas: n = 60, intraductal papillary mucinous tumor (IPMN) group: n = 60, IPMN-IC group: n = 12).

No significant differences were observed between the three groups in terms of age, sex, body mass index, diabetes prevalence, and hemoglobin A1c (p = 0.
141 to p = 0.
657).

Compared between the three groups, there was a significant difference in PDFF (p < 0.
001), and no significant difference in SIR-I, SIR-O, SIR-T2, ADC (p = 0.
153~p = 0.
684)
between the three groups.
The PDFF of pancreas in the IPMN-IC group was significantly higher than that in the normal pancreatic group or the IPMN group (p < 0.
001 and p < 0.
001, respectively), and there was no significant difference between the normal pancreas group and the IPMN group (p = 0.
916).

Figure 66-year-old woman, fatty liver
in the normal pancreatic group.
Measurement of region of interest (ROI) is performed at the head of the pancreas with axial isophase imaging (a), axial reverse phase imaging (b), axial T2-weighted imaging ( T2WI) (c), axial apparent diffusion coefficient (ADC) plot (d), and axial multi-echo 3D DIXON (e).

This study showed that the PDFF of pancreas in the IPMN-IC group was significantly higher than that in the normal pancreas group and the IPMN group, and the PDFF of the pancreas was correlated with
the presence of IPMN-IC.
Therefore, this study strongly recommends regular close monitoring of patients with IPMN with pancreatic fat infiltration to prevent the development
of PDAC.

Original source:

Hidemitsu Sotozono,Akihiko Kanki,Kazuya Yasokawa,et al.
Value of 3-T MR imaging in intraductal papillary mucinous neoplasm with a concomitant invasive carcinoma.
DOI:10.
1007/s00330-022-08881-6