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Mesopancreatic Stromal Clearance Defines Curative Resection of Pancreatic Head Cancer and Can Be Predicted Preoperatively by Radiologic Parameters

View Article: PubMed Central - PubMed

ABSTRACT

Pancreatic ductal adenocarcinoma (PDAC) is characterized by a strong fibrotic stromal reaction and diffuse growth pattern. Peritumoral fibrosis is often evident during surgery but only distinguishable from tumor by microscopic examination. The aim of this study was to investigate the role of clearance of fibrotic stromal reaction at the mesopancreatic resection margin as a criterion for radical resection and preoperative assessment of resectability.

Mesopancreatic stromal clearance status (S-status) was defined as the presence or absence (S+/S0) of fibrotic stromal reaction at the mesopancreatic resection margin. Detailed retrospective clinicopathologic re-evaluation of margin status and preoperative cross-sectional imaging was performed in a cohort of 91 patients operated for pancreatic head PDAC from 2001 to 2011.

Conventional margin positive resection (R+, tumor cells directly at the margin) was found in 36%. However, S-status further divided the margin negative (R0) group into patients with median survival of 14 months versus 31 months (S+ versus S0, P = 0.005). Overall rate of S+ was 53%. S-status and lymph node ratio constituted the only independent predictors of survival. Stranding of the superior mesenteric artery fat sheath was the only independent radiologic predictor of S+ resection, and achieved a 71% correct prediction of S-status.

Mesopancreatic stromal clearance is a major determinant of curative resection in PDAC, and preoperative prediction by cross-sectional imaging is possible, setting the basis for a new definition of borderline resectability.

No MeSH data available.


Related in: MedlinePlus

Assessment of radiologic parameters. A, Preoperative contrast enhanced multiphasic multidetector computed tomography (MDCT) demonstrating a normal fatty tissue sheath separating the superior mesenteric artery (SMA, arrow) and the inferior caval vein (ICV, arrowhead) from the pancreas. A small hypovascular/hypodense tumor in the pancreatic head can be seen. B, Preoperative contrast enhanced MDCT demonstrating the presence of stranding, that is increased attenuation, in the SMA fatty tissue sheath (arrow).
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Figure 2: Assessment of radiologic parameters. A, Preoperative contrast enhanced multiphasic multidetector computed tomography (MDCT) demonstrating a normal fatty tissue sheath separating the superior mesenteric artery (SMA, arrow) and the inferior caval vein (ICV, arrowhead) from the pancreas. A small hypovascular/hypodense tumor in the pancreatic head can be seen. B, Preoperative contrast enhanced MDCT demonstrating the presence of stranding, that is increased attenuation, in the SMA fatty tissue sheath (arrow).

Mentions: For preoperative staging and assessment of tumor resectability, patients routinely underwent a multiphasic multidetector computed tomography (MDCT) or a gadolinium-enhanced magnetic resonance imaging (MRI) including multiplanar sequences. Preoperative cross-sectional examinations were retrospectively reanalyzed by consensus reading by a clinically experienced radiologist and an experienced surgeon blinded for resection status. The raters evaluated each scan for 6 parameters. Thickness of the fatty tissue sheath between pancreas and superior mesenteric artery (SMA) and inferior caval vein (ICV) as well as distance between tumor and SMA / ICV was measured in millimeters (Figure 2). Furthermore, presence or absence of stranding within the fatty tissue sheaths was documented as positive or negative (Figure 2), and defined as positive when there was no fat sheath of 1 mm or more.


Mesopancreatic Stromal Clearance Defines Curative Resection of Pancreatic Head Cancer and Can Be Predicted Preoperatively by Radiologic Parameters
Assessment of radiologic parameters. A, Preoperative contrast enhanced multiphasic multidetector computed tomography (MDCT) demonstrating a normal fatty tissue sheath separating the superior mesenteric artery (SMA, arrow) and the inferior caval vein (ICV, arrowhead) from the pancreas. A small hypovascular/hypodense tumor in the pancreatic head can be seen. B, Preoperative contrast enhanced MDCT demonstrating the presence of stranding, that is increased attenuation, in the SMA fatty tissue sheath (arrow).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4998270&req=5

Figure 2: Assessment of radiologic parameters. A, Preoperative contrast enhanced multiphasic multidetector computed tomography (MDCT) demonstrating a normal fatty tissue sheath separating the superior mesenteric artery (SMA, arrow) and the inferior caval vein (ICV, arrowhead) from the pancreas. A small hypovascular/hypodense tumor in the pancreatic head can be seen. B, Preoperative contrast enhanced MDCT demonstrating the presence of stranding, that is increased attenuation, in the SMA fatty tissue sheath (arrow).
Mentions: For preoperative staging and assessment of tumor resectability, patients routinely underwent a multiphasic multidetector computed tomography (MDCT) or a gadolinium-enhanced magnetic resonance imaging (MRI) including multiplanar sequences. Preoperative cross-sectional examinations were retrospectively reanalyzed by consensus reading by a clinically experienced radiologist and an experienced surgeon blinded for resection status. The raters evaluated each scan for 6 parameters. Thickness of the fatty tissue sheath between pancreas and superior mesenteric artery (SMA) and inferior caval vein (ICV) as well as distance between tumor and SMA / ICV was measured in millimeters (Figure 2). Furthermore, presence or absence of stranding within the fatty tissue sheaths was documented as positive or negative (Figure 2), and defined as positive when there was no fat sheath of 1 mm or more.

View Article: PubMed Central - PubMed

ABSTRACT

Pancreatic ductal adenocarcinoma (PDAC) is characterized by a strong fibrotic stromal reaction and diffuse growth pattern. Peritumoral fibrosis is often evident during surgery but only distinguishable from tumor by microscopic examination. The aim of this study was to investigate the role of clearance of fibrotic stromal reaction at the mesopancreatic resection margin as a criterion for radical resection and preoperative assessment of resectability.

Mesopancreatic stromal clearance status (S-status) was defined as the presence or absence (S+/S0) of fibrotic stromal reaction at the mesopancreatic resection margin. Detailed retrospective clinicopathologic re-evaluation of margin status and preoperative cross-sectional imaging was performed in a cohort of 91 patients operated for pancreatic head PDAC from 2001 to 2011.

Conventional margin positive resection (R+, tumor cells directly at the margin) was found in 36%. However, S-status further divided the margin negative (R0) group into patients with median survival of 14 months versus 31 months (S+ versus S0, P = 0.005). Overall rate of S+ was 53%. S-status and lymph node ratio constituted the only independent predictors of survival. Stranding of the superior mesenteric artery fat sheath was the only independent radiologic predictor of S+ resection, and achieved a 71% correct prediction of S-status.

Mesopancreatic stromal clearance is a major determinant of curative resection in PDAC, and preoperative prediction by cross-sectional imaging is possible, setting the basis for a new definition of borderline resectability.

No MeSH data available.


Related in: MedlinePlus