45: Pancreatic Cancer



Key Points







  • Disease summary:




    • Pancreatic cancer, like many adult-onset malignancies, is a complex genetic disorder, with the majority of cases apparently sporadic, with some identified environmental factors.



    • Pancreatic cancer often presents in the later stages of life, with a median age of approximately 70 years at diagnosis.



    • There is no commonly accepted screening test for pancreatic cancer.



    • Pancreatic cancer often presents at an advanced stage, with only 15% to 20% of patients surgically resectable at diagnosis.







  • Differential diagnosis:




    • Cholelithiasis, peptic ulcer disease, poorly controlled type 2 diabetes, pancreatitis







  • Monogenic forms:




    • Pancreatic cancer can arise in Peutz-Jeghers syndrome, Li-Fraumeni syndrome, hereditary pancreatitis, and individuals who harbor mutations in BRCA1, BRCA2, and CDKN2A.







  • Family history:




    • 5% to 10% of pancreatic cancer patients report a family history of the disease.







  • Twin studies: There is no reported increased incidence in twins of pancreatic cancer beyond that expected for first-degree relatives.



  • Environmental factors:




    • Tobacco use, heavy alcohol use







  • Genome-wide associations:




    • Several associations exist, with the non-O blood type in the ABO gene (rs505922) now being consistently replicated.







  • Pharmacogenomics:




    • No pharmacogenetic or pharmacogenomic associations have been reported.








Diagnostic Criteria and Clinical Characteristics





Diagnostic evaluation should include both of the following:




  • Pancreas protocol computed tomography scan, which commonly shows a hypovascular mass in the pancreas



  • Needle biopsy of primary tumor confirming adenocarcinoma or other histology (can be done on metastases if present at diagnosis)



  • If pathologic confirmation is impractical, clinical diagnosis can be made in setting of pancreatic mass, elevated CA 19-9, and clinical syndrome including diabetes, weight loss, and epigastric pain.




And the absence of




  1. Other tumor causing pancreatic mass such as, lymphoma, metastasis from lung, kidney, melanoma.




Clinical Characteristics



Adenocarcinoma


The most common type of pancreatic cancer is adenocarcinoma, which comprises over 90% of pancreatic cancer. This type of malignancy has the poorest survival, and an expected prognosis of less than 6 months survival in advanced stages. For the minority of patients who present at a stage where surgical resection can be considered, full resection can offer a chance of cure. However, the vast majority of surgically resected patients will have a fatal recurrence of the disease. Adenocarcinoma is notoriously resistant to chemotherapy, though there have been recent studies suggesting higher responses to an aggressive combination regimen of irinotecan, oxaliplatin, 5-fluorouracil (5-FU), and leucovorin known as FOLFIRINOX.



Islet Cell Carcinoma


This less common malignancy of the pancreas is usually hormonally inactive. However, it is well known for its associated clinical hormonal syndromes such as insulinoma, gastrinoma, VIPoma, and glucagonoma. It may also be associated with the MEN1 syndrome, which often is associated with multiple pancreatic and duodenal tumors. Islet cell carcinoma appears more vascular on imaging studies than adenocarcinoma, and has a substantially better prognosis, often measured in years even for advanced disease.



Acinar Cell Carcinoma


This is a rare variant of pancreatic cancer emanating from the acinar cells, which produce the digestive enzymes released by the pancreas into the gut. This malignancy also has a good prognosis compared to adenocarcinoma.




Jun 2, 2016 | Posted by in HUMAN BIOLOGY & GENETICS | Comments Off on 45: Pancreatic Cancer

Full access? Get Clinical Tree

Get Clinical Tree app for offline access