Accurate prediction of nodal status in preoperative patients with pancreatic ductal adenocarcinoma using next-gen nanoparticle

Abstract

Objective: The objective of this study is to assess lymphotropic nanoparticle-enhanced magnetic resonance imaging (LNMRI) in identifying malignant nodal involvement in patients with pancreatic ductal adenocarcinoma.

Methods: Magnetic resonance imaging was performed in 13 patients with known or high index of suspicion of pancreatic cancer and who were scheduled for surgical resection. Protocols included T2*-weighted imaging before and after administration of Ferumoxytol (Feraheme) for the evaluation of lymph node involvement. Eleven of the 13 patients underwent a Whipple procedure and lymph node dissection. Nodes that lacked contrast uptake were deemed malignant, and those that demonstrated homogeneous uptake were deemed benign.

Results: A total of 264 lymph nodes were resection, of which 17 were malignant. The sensitivity and specificity of LNMRI was 76.5% and 98.4% at a nodal level and 83.3% and 80% at a patient level.

Conclusion: LNMRI demonstrated high sensitivity and specificity in patients with pancreatic ductal adenocarcinoma.

Figure 1

Scatter plot comparing the SNR of benign and malignant lymph nodes before and after the administration of ferumoxytol.

Figure 2

Benign lymph node. (A) Axial contrast-enhanced CT image shows a subcentimeter posterior pancreatic node (arrow). (B) Axial precontrast gradient-echo image shows a hyperintense portocaval node (arrow). (C) Forty-eight hours after ferumoxytol, the node shows a dramatic reduction in signal intensity indicating benignity (arrow). (D) Subsequent pathologic evaluation shows normal lymph node architecture.

Figure 3

Malignant lymph node. (A) Axial precontrast gradient-echo image shows a hyperintense peripancreatic node (arrow). (B) Forty-eight hours after ferumoxytol, the node shows no signal change indicating malignant infiltration. (C) Subsequent pathologic evaluation showed architectural distortion from malignant infiltration of pancreatic cancer.

Figure 4

(A) Axial gradient-echo image 48 hours after ferumoxytol administration shows a posterior lymph node that has homogenously low signal (arrow) consistent with a negative lymph node. (B) Subsequent pathologic evaluation found a small cluster of malignant cells (arrow).

Figure 5

There is a nodular area of high signal intensity (arrow) adjacent to the pancreatic mass on the precontrast T2-weighted image (A). This nodule did not change signal between the pre-ferumoxytol administration and 48 hours post-ferumoxytol administration (B) and was therefore called a metastatic node. On subsequent pathologic evaluation, this was found to be nodular extension of the primary tumor.