Carcinoma of Pancreas
Carcinoma of Pancreas
Overview
Cancer of EXOCRINE pancreas. Common in West+Japan. US: 2nd MC alimentary tract cancer after colorectal, ↑African Americans, 5% of all cancer deaths. More common MALES, ↑incidence after age 50.
Etiology
↑incidence UK/US last 50yrs, poorly understood. Factors:
- Smoking — heavy smokers ↑incidence, mechanism unclear
- Diet/obesity — high calorie/animal protein/fat, obesity=risk factor
- Chemical carcinogens — β-naphthylamine, benzidine, nitrosamines
- Diabetes mellitus — long-standing diabetics ↑incidence
- Chronic pancreatitis — increased risk
- H. pylori — reported association
- Genetic — 10% 1st-degree relatives; syndromes: Lynch, FPC, HNPCC
KEY CONTRAST: alcohol, coffee, cholelithiasis = NOT risk factors (unlike acute pancreatitis where alcohol+gallstones=80% of cases — different risk profiles despite both pancreatic diseases). K-RAS + CDKN2A mutation combo = almost ALL cases (unusually consistent molecular signature).
Morphology
Commonest: HEAD (70%) > body > tail.
Gross: Head=small, homogeneous, poorly-defined, grey-white, no sharp demarcation. Extends into ampulla/CBD/duodenum→EARLY obstructive jaundice (location dictates presentation timing). Body/tail=large, irregular, infiltrates transverse colon/stomach/liver/spleen/nodes.
Micro: mostly from DUCTAL epithelium (<4% of pancreatic cells but source of most cancers); acinar carcinoma <1%. Patterns:
- Well-differentiated adenocarcinoma(mucinous/non-mucin) — MOST COMMON. PERINEURAL INVASION = commonly present, DIAGNOSTIC of malignancy (high-yield)
- Adenoacanthoma — glandular+benign squamous elements
- Rare: tumour giant cells, marked anaplasia/pleomorphism
- Acinar cell carcinoma — rare, reproduces normal acini
Clinical features
- OBSTRUCTIVE JAUNDICE — frequent+EARLY with head CA(80%), less with body/tail. Dark urine, clay stools, pruritus, very high ALP
- Others: abdominal pain, anorexia, weight loss, cachexia, weakness, N/V, MIGRATORY THROMBOPHLEBITIS (TROUSSEAU’S SYNDROME — classic paraneoplastic clue, prompts pancreatic CA workup in unexplained hypercoagulable state), GI bleeding, splenomegaly
Prognosis
DISMAL — median survival 6 months. ~10% survive 1yr. 5yr survival 1-2%.
Clinical relevance
Head location→EARLY jaundice = anatomic proximity to ampulla/CBD explains presentation timing, NOT tumour biology — head tumours present earlier despite similar biology to body/tail. Alcohol/coffee/cholelithiasis NON-association = deliberately contrast against acute pancreatitis’s opposite profile (alcohol+gallstones=80%) — frequent confusion source. Perineural invasion = diagnostic-of-malignancy histologic fact, distinguishes malignant ductal CA from benign/reactive changes when differentiation grade ambiguous. Trousseau’s syndrome = classic pancreatic CA paraneoplastic trigger. K-RAS+CDKN2A near-universal combo = unusually consistent tumour genetics vs heterogeneous profiles in most other cancers.
Carcinoma of Pancreas
Overview
Cancer of EXOCRINE pancreas. Common in West+Japan. US: 2nd MC alimentary tract cancer after colorectal, ↑African Americans, 5% of all cancer deaths. More common MALES, ↑incidence after age 50.
Etiology
↑incidence UK/US last 50yrs, poorly understood. Factors:
- Smoking — heavy smokers ↑incidence, mechanism unclear
- Diet/obesity — high calorie/animal protein/fat, obesity=risk factor
- Chemical carcinogens — β-naphthylamine, benzidine, nitrosamines
- Diabetes mellitus — long-standing diabetics ↑incidence
- Chronic pancreatitis — increased risk
- H. pylori — reported association
- Genetic — 10% 1st-degree relatives; syndromes: Lynch, FPC, HNPCC
KEY CONTRAST: alcohol, coffee, cholelithiasis = NOT risk factors (unlike acute pancreatitis where alcohol+gallstones=80% of cases — different risk profiles despite both pancreatic diseases). K-RAS + CDKN2A mutation combo = almost ALL cases (unusually consistent molecular signature).
Morphology
Commonest: HEAD (70%) > body > tail.
Gross: Head=small, homogeneous, poorly-defined, grey-white, no sharp demarcation. Extends into ampulla/CBD/duodenum→EARLY obstructive jaundice (location dictates presentation timing). Body/tail=large, irregular, infiltrates transverse colon/stomach/liver/spleen/nodes.
Micro: mostly from DUCTAL epithelium (<4% of pancreatic cells but source of most cancers); acinar carcinoma <1%. Patterns:
- Well-differentiated adenocarcinoma(mucinous/non-mucin) — MOST COMMON. PERINEURAL INVASION = commonly present, DIAGNOSTIC of malignancy (high-yield)
- Adenoacanthoma — glandular+benign squamous elements
- Rare: tumour giant cells, marked anaplasia/pleomorphism
- Acinar cell carcinoma — rare, reproduces normal acini
Clinical features
- OBSTRUCTIVE JAUNDICE — frequent+EARLY with head CA(80%), less with body/tail. Dark urine, clay stools, pruritus, very high ALP
- Others: abdominal pain, anorexia, weight loss, cachexia, weakness, N/V, MIGRATORY THROMBOPHLEBITIS (TROUSSEAU’S SYNDROME — classic paraneoplastic clue, prompts pancreatic CA workup in unexplained hypercoagulable state), GI bleeding, splenomegaly
Prognosis
DISMAL — median survival 6 months. ~10% survive 1yr. 5yr survival 1-2%.
Clinical relevance
Head location→EARLY jaundice = anatomic proximity to ampulla/CBD explains presentation timing, NOT tumour biology — head tumours present earlier despite similar biology to body/tail. Alcohol/coffee/cholelithiasis NON-association = deliberately contrast against acute pancreatitis’s opposite profile (alcohol+gallstones=80%) — frequent confusion source. Perineural invasion = diagnostic-of-malignancy histologic fact, distinguishes malignant ductal CA from benign/reactive changes when differentiation grade ambiguous. Trousseau’s syndrome = classic pancreatic CA paraneoplastic trigger. K-RAS+CDKN2A near-universal combo = unusually consistent tumour genetics vs heterogeneous profiles in most other cancers.
Carcinoma of Pancreas
Overview
Pancreatic cancer refers to cancer of the exocrine pancreas. One of the common cancers, particularly in Western countries and Japan. In the US, it is the second most common alimentary tract cancer after colorectal cancer, more common in African Americans, and accounts for 5% of all cancer deaths there. More common in males; incidence rises progressively after age 50.
Etiology
Incidence has significantly risen in the UK and US over the last 50 years; etiology remains poorly understood, but several factors are implicated:
- Smoking — heavy smokers show higher incidence than non-smokers; the direct-carcinogenic-vs-indirect mechanism is unclear.
- Diet and obesity — high total caloric intake and high animal protein/fat consumption correlate with higher incidence; obesity is a risk factor.
- Chemical carcinogens — β-naphthylamine, benzidine, nitrosamine exposure raises incidence.
- Diabetes mellitus — long-standing diabetics show higher incidence.
- Chronic pancreatitis — patients are at increased risk.
- H. pylori infection — reported association.
- Genetic factors — occurs in first-degree relatives in 10% of cases; associated hereditary syndromes: Lynch syndrome, familial pancreatic cancer (FPC), HNPCC.
Notably, excessive alcohol or coffee consumption and cholelithiasis are NOT risk factors for pancreatic cancer (a genuine contrast with acute pancreatitis’s etiology). A combination of K-RAS gene and CDKN2A gene mutations is found in almost all cases.
Morphology
Commonest location: head of pancreas (70%), then body and tail in decreasing frequency.
Gross: carcinoma of the head — small, homogeneous, poorly-defined, grey-white mass without sharp demarcation from surrounding parenchyma; extends into the ampulla of Vater, common bile duct, and duodenum, producing obstructive biliary symptoms and jaundice early in the disease course. Carcinomas of the body/tail — fairly large, irregular masses, frequently infiltrating the transverse colon, stomach, liver, spleen, and regional lymph nodes.
Micro: most pancreatic carcinomas arise from ductal epithelium (despite comprising <4% of total pancreatic cells); acinar-cell carcinoma accounts for <1% of pancreatic cancers. Histologic patterns:
- Well-differentiated adenocarcinoma (mucinous or non-mucin-secreting) — the most common pattern. Perineural invasion is commonly present and is diagnostic of malignancy.
- Adenoacanthoma — glandular carcinoma with benign squamous elements, in a proportion of cases.
- Rarely, tumour giant cell formation with marked anaplasia, pleomorphism, numerous mitoses.
- Acinar cell carcinoma — rare, reproduces normal pancreatic acinar architecture.
Clinical Features
Symptoms depend on tumour location:
- Obstructive jaundice — frequent and early with carcinoma of the head (80%), less often with body/tail cancer. Features: dark urine, clay-coloured stools, pruritus, very high serum alkaline phosphatase.
- Other features: abdominal pain, anorexia, weight loss, cachexia, weakness, malaise, nausea, vomiting, migratory thrombophlebitis (Trousseau’s syndrome), GI bleeding, splenomegaly.
Prognosis
Dismal — median survival 6 months from diagnosis; ~10% survive 1 year; 5-year survival only 1–2%.
Clinical Relevance
- Head-of-pancreas cancer’s anatomic position explains its own clinical presentation directly: proximity to the ampulla/common bile duct produces early obstructive jaundice, which is precisely why head tumours (despite being biologically similar to body/tail tumours) tend to present earlier and are occasionally more resectable — location dictates presentation timing here, not tumour biology.
- The alcohol/coffee/cholelithiasis non-association is worth deliberately contrasting against acute pancreatitis’s etiology (where alcohol and gallstones are the two leading causes, >80% of cases) — these are genuinely different risk-factor profiles despite both being pancreatic diseases, a frequent source of confusion.
- Perineural invasion being specifically called out as diagnostic of malignancy is a high-yield histologic fact — its presence helps distinguish malignant ductal carcinoma from benign/reactive changes when the differentiation grade alone is ambiguous.
- Trousseau’s syndrome (migratory thrombophlebitis) is the classic paraneoplastic clue most associated with pancreatic cancer specifically — worth flagging as a diagnostic trigger prompting pancreatic cancer workup in an otherwise unexplained hypercoagulable presentation.
- The near-uniform K-RAS + CDKN2A mutation combination is worth remembering as one of medicine’s most consistent tumour-genetics findings — almost every case shares this molecular signature, unlike many other cancers with more heterogeneous mutation profiles.
Carcinoma of Pancreas
Overview
Pancreatic cancer refers to cancer of the exocrine pancreas. One of the common cancers, particularly in Western countries and Japan. In the US, it is the second most common alimentary tract cancer after colorectal cancer, more common in African Americans, and accounts for 5% of all cancer deaths there. More common in males; incidence rises progressively after age 50.
Etiology
Incidence has significantly risen in the UK and US over the last 50 years; etiology remains poorly understood, but several factors are implicated:
- Smoking — heavy smokers show higher incidence than non-smokers; the direct-carcinogenic-vs-indirect mechanism is unclear.
- Diet and obesity — high total caloric intake and high animal protein/fat consumption correlate with higher incidence; obesity is a risk factor.
- Chemical carcinogens — β-naphthylamine, benzidine, nitrosamine exposure raises incidence.
- Diabetes mellitus — long-standing diabetics show higher incidence.
- Chronic pancreatitis — patients are at increased risk.
- H. pylori infection — reported association.
- Genetic factors — occurs in first-degree relatives in 10% of cases; associated hereditary syndromes: Lynch syndrome, familial pancreatic cancer (FPC), HNPCC.
Notably, excessive alcohol or coffee consumption and cholelithiasis are NOT risk factors for pancreatic cancer (a genuine contrast with acute pancreatitis’s etiology). A combination of K-RAS gene and CDKN2A gene mutations is found in almost all cases.
Morphology
Commonest location: head of pancreas (70%), then body and tail in decreasing frequency.
Gross: carcinoma of the head — small, homogeneous, poorly-defined, grey-white mass without sharp demarcation from surrounding parenchyma; extends into the ampulla of Vater, common bile duct, and duodenum, producing obstructive biliary symptoms and jaundice early in the disease course. Carcinomas of the body/tail — fairly large, irregular masses, frequently infiltrating the transverse colon, stomach, liver, spleen, and regional lymph nodes.
Micro: most pancreatic carcinomas arise from ductal epithelium (despite comprising <4% of total pancreatic cells); acinar-cell carcinoma accounts for <1% of pancreatic cancers. Histologic patterns:
- Well-differentiated adenocarcinoma (mucinous or non-mucin-secreting) — the most common pattern. Perineural invasion is commonly present and is diagnostic of malignancy.
- Adenoacanthoma — glandular carcinoma with benign squamous elements, in a proportion of cases.
- Rarely, tumour giant cell formation with marked anaplasia, pleomorphism, numerous mitoses.
- Acinar cell carcinoma — rare, reproduces normal pancreatic acinar architecture.
Clinical Features
Symptoms depend on tumour location:
- Obstructive jaundice — frequent and early with carcinoma of the head (80%), less often with body/tail cancer. Features: dark urine, clay-coloured stools, pruritus, very high serum alkaline phosphatase.
- Other features: abdominal pain, anorexia, weight loss, cachexia, weakness, malaise, nausea, vomiting, migratory thrombophlebitis (Trousseau’s syndrome), GI bleeding, splenomegaly.
Prognosis
Dismal — median survival 6 months from diagnosis; ~10% survive 1 year; 5-year survival only 1–2%.
Clinical Relevance
- Head-of-pancreas cancer’s anatomic position explains its own clinical presentation directly: proximity to the ampulla/common bile duct produces early obstructive jaundice, which is precisely why head tumours (despite being biologically similar to body/tail tumours) tend to present earlier and are occasionally more resectable — location dictates presentation timing here, not tumour biology.
- The alcohol/coffee/cholelithiasis non-association is worth deliberately contrasting against acute pancreatitis’s etiology (where alcohol and gallstones are the two leading causes, >80% of cases) — these are genuinely different risk-factor profiles despite both being pancreatic diseases, a frequent source of confusion.
- Perineural invasion being specifically called out as diagnostic of malignancy is a high-yield histologic fact — its presence helps distinguish malignant ductal carcinoma from benign/reactive changes when the differentiation grade alone is ambiguous.
- Trousseau’s syndrome (migratory thrombophlebitis) is the classic paraneoplastic clue most associated with pancreatic cancer specifically — worth flagging as a diagnostic trigger prompting pancreatic cancer workup in an otherwise unexplained hypercoagulable presentation.
- The near-uniform K-RAS + CDKN2A mutation combination is worth remembering as one of medicine’s most consistent tumour-genetics findings — almost every case shares this molecular signature, unlike many other cancers with more heterogeneous mutation profiles.
Carcinoma of Pancreas
- Pancreatic cancer distribution by site (head 70%/body/tail) with each site’s characteristic spread pattern and presentation
- Head-of-pancreas tumour anatomic relationship to ampulla of Vater and common bile duct, showing why obstructive jaundice occurs early
Carcinoma of Pancreas
- Pancreatic cancer distribution by site (head 70%/body/tail) with each site’s characteristic spread pattern and presentation
- Head-of-pancreas tumour anatomic relationship to ampulla of Vater and common bile duct, showing why obstructive jaundice occurs early
My Sticky Notes
Personal revision notes, mnemonics and reminders.
