Pancreas Flashcards
percent of pancreatic cancer eligible for resection
20%
Best prognostic subtype of PDAC
colloid carcinoma
Head v tail proportion of PDAC
65% head v 25% tail (rest is indeterminate)
possible cutaneous presentations of PDAC
Pemphigoid rash (cicatricial and bullous)
Imaging features of a PNET
highly vascular
early arterial enhancement
washout in the early portal phase
Sensitivity and specificity of CA 19-9
sensitivity 70 to 92%
Specificity 68 to 92%
Positive predictive value of CA19-9 in asymptomatic patient?
i.e. can we screen for PDAC with CA19-9
<1%
PMID 14731128
(no)
What is the utility of CA-19-9 to plan for surgery?
Do not use as indicator of operability (ASCO)
May become part of selection criteria for neoadjuvant therapy.
When to biopsy prior to operating on PDAC?
Concern for:
chronic pancreatitis
autoimmune pancreatitis
(eg, extreme young age, prolonged ethanol abuse, history of other autoimmune diseases),
First-line biopsy procedure (if necessary) for PDAC?
EUS-guided FNA
NCCN unresectable definition for head PDAC
- contact with SMA >180 degrees
- contact with celiac axis >180 degrees
- tumor contact with the first jejunal SMA branch
- Unreconstructable SMV or portal vein
- Contact with the most proximal draining jejunal branch into the SMV
NCCN unresectable definition for tail PDAC
- Solid tumor contact of >180 degrees with the SMA or celiac axis
- Solid tumor contact with the celiac axis and aortic involvement
- Unreconstructable SMV or portal vein due to tumor involvement or occlusion (thrombus)
NCCN borderline resectable definition for head PDAC
SMV or portal vein
>180 degrees contact with contour irregularity
or thrombosis of the vein.
inferior vena cava.
tumor contact
Solid tumor contact with the SMA ≤180 degrees.
Solid tumor contact with variable anatomy
NCCN borderline resectable definition for tail PDAC
- Solid tumor contact with the celiac axis of ≤180 degrees.
- Solid tumor contact with the celiac axis >180 degrees without involvement of the aorta and withpreserved GDA, permitting an Appleby procedure (controverisal).
Discrepancy between AJCC and “borderline resectable” PDAC in 7th edition AJCC
7th Ed AJCC uses T4 category to designate an unresectable primary tumor. However T4s (arterial involvement) are still resected with R0 margins at some centers, especially after neoadjuvant therapy.
Ability of CT scan to detect metastatic PDAC
Contrast-enhanced CT is the modality of choice to detect distant metastases (image 16). with ~90% sensitivity and specificity.
However, the sensitivity of CT for peritoneal dissemination not high to eliminate the need for diagnostic laparoscopy in equivocal cases.
Role of Chest CT and PET in PDAC
Chest CT — most centers do not perform a routine staging chest CT for patients suspected of having pancreatic cancer because in the presence of lung metastases, the primary tumor is usually unresectable for another reason.
PET scanning — Studied, and probably not useful. In uncontrolled studies and meta-analyses, the sensitivity of integrated PET/CT (which has better spatial resolution as compared to PET alone) in the initial diagnosis of pancreatic cancer has ranged from 73 to 94 percent, while specificity ranges from 60 to 89 percent.
Role of staging laparoscopy in PDAC?
Widespread acceptance, but no controlled studies demonstrate a benefit.
Some selectively perform for borderline tumors, CA19-9 >1000, and prior to neoadjuvant therapy.
Good idea to do to avoid giving RT to peritoneal disease.
Peritoneal cytology in PDAC?
Not routinely reccomended as most patients with positive cytology have additional features of unresectability.
[PMID 15055843 MEYERS paper]
summary of resectability of PDAC
Remains controversial and somewhat of a continuum:
• nodal involvement beyond the peripancreatic tissues, and/or distant metastases.
•Direct involvement of the superior mesenteric artery (SMA), CHA, Celiac, by CT scan of low density tumor.
•Encasement or occlusion/thrombus of the superior mesenteric vein (SMV) or the SMV-portal vein
in practice, most of these patients are referred for neoadjuvant therapy prior to surgery.
T Staging of Pancreatic Cancer (PDAC and PNET)
Primary tumor (T) TX Primary tumor cannot be assessed T0 No evidence of primary tumor Tis Carcinoma in situ* T1 < 2 cm or less in greatest dimension T2 > 2 cm in greatest dimension T3 Tumor extends beyond the pancreas but without involvement of the celiac axis or the superior mesenteric artery T4 Tumor involves the celiac axis or the superior mesenteric artery (unresectable primary tumor)
Stage 0, IA, IB and IIA for PDAC (it’s simple!)
Anatomic stage/prognostic groups Stage 0 Tis N0 M0 Stage IA T1 N0 M0 Stage IB T2 N0 M0 Stage IIA T3 N0 M0
N Staging of Pancreatic Cancer
N0 or N1
What phase of CT scan is best for determining liver mets?
also occurs in the portal venous phase i.e. peak hepatic enhancement
