What Is Pancreatic Cancer?

Pancreatic cancer is a malignancy arising in the tissues of the pancreas, the retroperitoneal gland that produces digestive enzymes and the hormones insulin and glucagon. More than 90 percent of cases are pancreatic ductal adenocarcinoma, which originates in the epithelium lining the pancreatic duct. The remainder are pancreatic neuroendocrine tumors and rarer histologies, which behave differently and carry a far better prognosis. Because the pancreas sits deep in the abdomen and early tumors produce no distinctive symptoms, the disease is usually advanced at the point of diagnosis.

That late presentation drives the outcome statistics. US surveillance data record a five-year relative survival of about 13.7 percent, with roughly half of all cases already metastatic when found. Pancreatic cancer accounts for a small share of new cancer diagnoses but a much larger share of cancer deaths, and it is projected to become one of the leading causes of cancer mortality in high-income countries as other cancers become more treatable.

Molecular Pathology

Ductal adenocarcinoma develops through a stepwise progression from precursor lesions, principally pancreatic intraepithelial neoplasia and, less often, intraductal papillary mucinous neoplasm. The genetic sequence is unusually consistent: activating mutation of the KRAS oncogene appears in the large majority of tumors, most commonly at codon 12, followed by loss of the tumor suppressors CDKN2A, TP53, and SMAD4. KRAS resisted pharmacologic attack for decades, and work on direct KRAS inhibitors is among the most active areas in the field. About one case in ten has a hereditary component, involving germline variants in BRCA1, BRCA2, PALB2, ATM, or the mismatch repair genes of Lynch syndrome, which has practical consequences for family screening and for eligibility for PARP inhibitor therapy.

A second defining feature is the tumor microenvironment. Pancreatic tumors provoke a dense desmoplastic stroma of activated fibroblasts and extracellular matrix that compresses vasculature, raises interstitial pressure, and limits the delivery of systemic agents. That physical barrier, combined with an immunosuppressive immune infiltrate, explains much of the poor response to chemotherapy and to immune checkpoint blockade.

Detection and Imaging

Diagnosis relies on contrast-enhanced pancreatic protocol computed tomography to assess the primary lesion and its relationship to the superior mesenteric artery and vein, supplemented by magnetic resonance cholangiopancreatography and by endoscopic ultrasound with fine-needle aspiration for tissue. The serum marker CA 19-9 is used for monitoring rather than screening, since it lacks the specificity for population use. Screening is currently limited to high-risk individuals with hereditary syndromes or a strong family history. Reviews of early detection strategies describe circulating tumor DNA assays, methylation and protein biomarker panels, and machine learning models applied to routine imaging and electronic health records as the main candidate approaches for catching disease at a resectable stage.

Treatment

Surgical resection remains the only path to cure, and only a minority of patients are anatomically eligible. Tumors of the head of the pancreas are removed by pancreaticoduodenectomy, the Whipple procedure; body and tail tumors by distal pancreatectomy. Multiagent chemotherapy, most often FOLFIRINOX or gemcitabine with nab-paclitaxel, is given adjuvantly after resection and as first-line treatment in advanced disease, with neoadjuvant use expanding for borderline resectable tumors. Radiation therapy, including stereotactic body radiotherapy, is used selectively for local control.

Applications

Research on pancreatic cancer intersects with a range of fields, including:

• Medical imaging and computer-aided detection
• Liquid biopsy and biomarker assay development
• Targeted drug discovery and structural biology
• Surgical robotics and image-guided intervention
• Cancer epidemiology and screening program design
• Organoid and animal model systems for drug testing