Pancreatic tumours
How pancreatic ductal adenocarcinoma grows from precursor lesions and invades early, why a tumour of the head causes painless jaundice while one in the body or tail is found late, and the cystic and neuroendocrine tumours of the pancreas.
By the end, you can
- Relate the ducts, acini and islets of the pancreas to the tumours that arise from each.
- Explain the progression from pancreatic intraepithelial neoplasia to ductal adenocarcinoma and its main genetic changes.
- Explain why pancreatic cancer invades early and why its site in the gland shapes how it presents.
- Distinguish the main cystic neoplasms of the pancreas by their lining, contents and malignant potential.
- Relate functioning pancreatic neuroendocrine tumours to the hormones they secrete.
- Recognise the classic appearances, resectability categories and tests of pancreatic tumours, and explain how surgery, chemotherapy, enzyme replacement and neuroendocrine treatments act on the mechanism.
What it is
Most pancreatic cancers are pancreatic ductal adenocarcinomas (PDAC): infiltrating, duct-like malignant glands in a dense fibrous stroma, which invade early and are usually advanced when found. The pancreas also gives rise to cystic neoplasms, some benign and some precursors of cancer, to neuroendocrine tumours of the islet cells, which may secrete hormones, and to rarer tumours such as acinar cell carcinoma.
5 types to tell apart
- Pancreatic ductal adenocarcinoma
- Roughly nine in ten pancreatic cancers; most arise in the head. Infiltrating glands in a dense desmoplastic stroma, with a marked tendency to invade nerves.
- Intraductal papillary mucinous neoplasm (IPMN)
- A mucin-secreting papillary growth inside the main duct or its branches, which it dilates; involvement of the main duct carries the higher risk of cancer.
- Mucinous cystic neoplasm (MCN)
- A mucin-filled cyst, almost always in women and in the body or tail, with an ovarian-type stroma and no connection to the ducts; it can progress to carcinoma.
- Serous cystic neoplasm
- Serous cystadenoma: many tiny cysts lined by glycogen-rich cells, often round a central scar; almost always benign, and associated with von Hippel–Lindau disease.
- Pancreatic neuroendocrine tumour (PanNET)
- Arises from islet cells; most secrete no hormone, but functioning tumours cause insulin, gastrin, glucagon or VIP excess. Graded 1 to 3 by proliferation; associated with MEN1.
US spelling: tumours → tumors.
Normal function
Ducts, acini and islets
The pancreas lies across the back of the upper abdomen: its sits in the curve of the , its crosses the spine and its reaches the spleen. The runs through the head to join the , and both open at the .
Most of the gland is exocrine. Clusters of acinar cells secrete digestive enzymes into small ducts lined by cuboidal cells that add bicarbonate; the ducts merge into the main duct. Scattered among the acini, the islets of Langerhans (a few per cent of the gland) contain beta cells (insulin), alpha cells (glucagon), delta cells (somatostatin) and others.
Each cell type gives rise to its own tumours: the duct lining to ductal adenocarcinoma and the mucinous cystic tumours, the islet cells to neuroendocrine tumours, and the acinar cells, rarely, to acinar cell carcinoma.
Underlying change · Step 1 of 5
From PanIN to invasive carcinoma
The full lesson is part of Student Pro
It takes you through all 5 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Disrupted function · Step 2 of 5
A tumour of the head blocks the ducts
The full lesson is part of Student Pro
It takes you through all 5 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Consequences · Step 3 of 5
Silent growth, spread and effects on the body
The full lesson is part of Student Pro
It takes you through all 5 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Underlying change · Step 4 of 5
Cystic neoplasms: benign, precursor or malignant
The full lesson is part of Student Pro
It takes you through all 5 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Consequences · Step 5 of 5
Neuroendocrine tumours: too much of one hormone
The full lesson is part of Student Pro
It takes you through all 5 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Symptoms and signs
Symptoms, signs and findings
The full lesson is part of Student Pro
It takes you through all 5 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Exam detail
Exam detail
The full lesson is part of Student Pro
It takes you through all 5 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Treatment
How treatment works
The full lesson is part of Student Pro
It takes you through all 5 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Recap
Recap
The full lesson is part of Student Pro
It takes you through all 5 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Self-check
Check your understanding
The full lesson is part of Student Pro
It takes you through all 5 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .