European Radiology: CEUS "live use" in diagnosing pancreatic ductal adenocarcinoma

Pancreatic cancer is known to have a very poor prognosis and high mortality rate, and is the seventh leading cause of cancer death in the world, causing 460,000 deaths
in 2020.
Pancreatic ductal adenocarcinoma (PDAC) accounts for 85-95% of pancreatic malignant diseases and is the most common malignancy of
the pancreas.
PDACs have a 1-year survival rate of less than 20% and a 5-year survival rate of less than 5%, posing a huge challenge
to human health.

In the 2017 EFSUMB Clinical Practice Guidelines and Recommendations for Non-Hepatic Applications of Enhanced Ultrasound (CEUS), CEUS states that CEUS is not suitable for the detection of focal solid or cystic lesions of the pancreas, but CEUS can improve the characteristics of lesions seen in US, and for solid lesions of the pancreas detected by ultrasound, CEUS can be used to reliably describe PDACs
.
CEUS plays an important role in the diagnosis of PDAC, especially compared to grayscale ultrasound, CEUS can provide more image information
that helps to clarify the diagnosis.
The differences in microcirculation in different solid pancreatic lesions provide a pathological basis
for the characterization of CEUS features.
The contrast agent microvesicle used in CEUS is a pure-blood pool contrast agent that better mimics the microvascular condition
of the lesion.
At the same time, CEUS has no obvious toxicity and adverse reactions, and can be applied to patients with
hepatic and renal insufficiency and chronic obstructive pulmonary disease.

Recently, a study published in the journal European Radiology evaluated the EFSUMB guidelines for the diagnostic performance and recommendations of CEUS clinical practice for solid pancreatic lesions, and further explored the ability
of CEUS in the differential diagnosis and prognosis prediction of PDAC.

This retrospective study evaluated
patients diagnosed with solid pancreatic lesions from January 2017 to December 2020.
According to EFSUMB guidelines, pancreatic ductal adenocarcinoma (PDAC) presents with low enhancement
at all stages.
First of all, according to this definition, all lesions are classified as PDAC and non-PDAC
.
Then, isokinetic enhancement and very rapid/rapid clearance were added as supplementary diagnostic criteria, and all lesions were reclassified
.
Diagnostic performance was assessed
in terms of accuracy (ACC), sensitivity (SEN), specificity (SPE), positive predictive value (PPV), and negative predictive value (NPV).
Reference standards include histological assessment or composite imaging and clinical follow-up results
.

There were 450 patients in total (median age, 58.
37 years; 250 men) 455 lesions were included
.
The diagnostic performance of PDAC using EFSUMB CEUS guidelines was 69.
5% for ACC, 65.
4% for SEN, 84% for SPE, 93.
5% for PPV, 40.
6% for NPV and 0.
747
for ROC.
After reclassification according to supplementary diagnostic criteria, the diagnosis of PDAC showed an ACC of 95.
8%, SEN of 99.
2%, SPE of 84%, PPV of 95.
7%, NPV of 96.
6%, and ROC of 0.
916
.

Figure CEUS et al.
enhanced with pathologically confirmed images
of non-PDAC.
a-c A 67-year-old female patient with TB with equal enhancement located at the unterminal end of the pancreas (arrow); CEUS image display such as enhancement (a, b) and synchronization (c).

d-f A 49-year-old male patient with p-NEN G1 with iso-enhancement located in the neck of the pancreas (arrow); CEUS images show such enhancement (d, e) and slow clearance (f).

This study suggests that the 2017 EFSUMB guidelines and recommended versions of pancreatic lesions are an effective and practical diagnostic tool
for predicting the risk of PDAC.
Modifications to these guidelines to include isokinetic enhancement with very fast/fast clearance modes can improve diagnostic performance
in differentiating PDAC from non-PDAC.
CEUS can provide richer, real-time perfusion information for PDAC lesions and can be a useful tool
for therapeutic monitoring of patients with primary PDAC and those who are not surgical candidates in a neoadjuvant setting.

Original source:

Wan-Ying Jia,Yang Gui,Xue-Qi Chen,et al.
Evaluation of the diagnostic performance of the EFSUMB CEUS Pancreatic Applications guidelines (2017 version): a retrospective single-center analysis of 455 solid pancreatic masses.
DOI:10.
1007/s00330-022-08879-0.