Pancreatic Cancer¶
Part 4: Oncology and Hematology · Part 4 – Oncology: Solid Tumors · Part 4 – Oncology: Solid Tumors · Chapter 88
Key Clinical Points¶
- Pancreatic cancer is the third leading cause of cancer-related mortality in the U.S., with a 13% overall 5-year survival rate.
- Cigarette smoking is the primary risk factor, contributing to 25–30% of cases.
- High BMI (≥30) doubles the risk of pancreatic cancer.
- Molecular profile: KRAS mutations in 90–95%, TP53 in ~75%, and DPC4/SMAD4 in ~50%.
- mFOLFIRINOX is the preferred adjuvant therapy for fit patients (median survival 54 months vs. 35 months for gemcitabine).
- PARP inhibitors are indicated for metastatic disease with BRCA1, BRCA2, or PALB2 germline variants.
- CA19-9 is a useful marker but is not useful in Lewis antigen non-secretors.
- Trousseau's syndrome (migratory thrombophlebitis) and Virchow's node are classic signs of advanced disease.
- Neoadjuvant therapy is the standard for borderline resectable or locally advanced disease to assess biology and downstage.
- Screening is only indicated for high-risk groups (e.g., BRCA1/2, PALB2, family history).
DEFINITION & CLASSIFICATION¶
• Overview: Third leading cause of cancer mortality in the U.S.; projected to be second leading globally by 2030. • Survival Rates: ◦ Localized: 44% ◦ Regional: 16% ◦ Metastatic: 3.2%
Epidemiology & Survival¶
• Incidence: ~3% of new cases in U.S.; 8.3% of cancer-related deaths. • Risk Trends: Lifetime risk ~1.7%; incidence increasing by 1.1% annually (faster growth in those <55).
EPIDEMIOLOGY¶
• Demographics: Most common in ages 65–79; higher incidence in males and Black individuals. • Risk Factors: ◦ Environmental: Cigarette smoking (25–30% of cases); high fat/meat diet, low fruit/veg intake. ◦ Hereditary: 10–16% of cases linked to genetic syndromes (e.g., BRCA2, CDKN2A). ◦ Other: Obesity (BMI ≥30), physical inactivity, diabetes; Non-O blood type.
Screening & High-Risk Populations¶
• Average Risk: No screening recommended. • High Risk: Screening indicated for BRCA1/2, PALB2, CDKN2A, STK11, or significant family history. ◦ Family History: 4.6-fold risk with one first-degree relative; 32-fold with ≥3 affected relatives. • Table 88-1: Lists germline mutations and associated syndromes (e.g., PRSS1/SPIN11b for hereditary pancreatitis, STK11 for Peutz-Jeghers).
ETIOLOGY & PATHOPHYSIOLOGY¶
• Precursor Lesions: ◦ PanIN (grades 1–3) → progression to invasive cancer. ◦ IPMN: Main duct type more likely malignant; side branch type often benign. ◦ Mucinous cystic neoplasms: More common in women, lower malignancy risk. • Molecular Characteristics: ◦ KRAS mutations: 90–95% of ductal adenocarcinomas. ◦ TP53: ~75%. ◦ SMAD4: ~50%. ◦ BRCA2: 3.5–10% (Table 88-1). • Pathology: ◦ Desmoplastic reaction: Dense fibrotic stroma (Figure 88-1) leads to vessel/nerve compression and poor prognosis.
CLINICAL FEATURES¶
• Symptoms: ◦ Painless jaundice (bilirubin >2 mg/dL; common in head of pancreas tumors). ◦ Epigastric pain radiating to back. ◦ Weight loss, steatorrhea, new-onset diabetes. ◦ Pruritus from bile salts. • Physical Examination Findings: ◦ Courvoisier's sign: Palpable gallbladder with biliary obstruction. ◦ Trousseau's syndrome: Migratory superficial thrombophlebitis (indicates hypercoagulable state). ◦ Virchow's node: Left supraclavicular lymphadenopathy. ◦ Sister Mary Joseph's node: Periumbilical metastasis.
Clinical Significance of Signs¶
• Trousseau's syndrome → strong indicator of occult malignancy.
DIFFERENTIAL DIAGNOSIS¶
• Biliary Obstruction: Distinguish from choledocholithiasis (Charcot's triad: pain, fever, jaundice). ◦ Courvoisier's sign → suggests malignancy over stone. • Weight Loss & Epigastric Pain: ◦ Chronic pancreatitis vs. cancer: Cancer often presents with steatorrhea and back radiation of pain. ◦ Other differentials: Gastric malignancy, lymphoma, peptic ulcer disease.
DIAGNOSTIC APPROACH¶
- Imaging: ◦ Dual-phase CT: Evaluate vascular involvement (e.g., SMA, portal vein) and resectability. ◦ PET-CT: Identify occult metastases (Figure 88-3). ◦ Laparoscopy: Identify metastatic disease preoperatively.
- Histologic Confirmation: ◦ Tru-Cut biopsy preferred for tissue sampling.
- Molecular & Biomarker Testing: ◦ KRAS, microsatellite status, and BRCA/PALB2 status to guide therapy. ◦ CA19-9: Serum marker; note that it is non-detectable in Lewis antigen non-secretors.
Staging (AJCC)¶
• T Category: ◦ TX: Not assessable. ◦ Tis: Carcinoma in situ (PanIN-3, IPMN with high-grade dysplasia). ◦ T1: ≤2 cm. ◦ T4: Involves celiac axis, SMA, or common hepatic artery. • N Category: ◦ NX: Not assessable; N0: No regional nodes; N1: 1–3 nodes. • M Category: ◦ M0: No distant metastasis; M1: Distant metastasis. • Prognostic Stage Groups (Table 88-4): ◦ Stage 0: Tis, N0, M0. ◦ Stage IA: T1, N0, M0. ◦ Stage IB: T2, N0, M0. ◦ Stage IIA: T3, N0, M0. ◦ Stage IIB: T1/T2/T3 with N1; or T4 with any N and M0. ◦ Stage III: T1/T2/T3 with N2; or T4 with any N and M0. ◦ Stage IV: Any T, Any N, M1.
MANAGEMENT & TREATMENT¶
- Resectable Disease (Table 88-3): • Criteria: No solid tumor contact with celiac axis, hepatic artery, or SMA; contact with superior mesenteric–portal veins <180°; patent superior mesenteric–portal veins; no extrapancreatic disease. • Action: Surgery (pancreaticoduodenectomy or distal pancreatectomy) → followed by adjuvant therapy. • Adjuvant Options: mFOLFIRINOX or gemcitabine ± capecitabine or nab-paclitaxel.
- Locally Advanced Disease: • Action: Neoadjuvant chemotherapy to assess tumor biology and attempt downstaging for margin-negative resection. • Comparison: mFOLFIRINOX (median survival 54 months) vs. gemcitabine alone (35 months).
- Metastatic Disease: • Systemic Therapy: PARP inhibitors for patients with BRCA1, BRCA2, or PALB2 mutations. • Supportive Care: ◦ Anticoagulation (DOACs or LMWH) for Trousseau's syndrome. ◦ PERT for malabsorption symptoms. ◦ Opioids/nerve blocks for pain management.
Supportive Care¶
• Nutrition: PERT for exocrine insufficiency; nutritional support for weight loss.
COMPLICATIONS & PROGNOSIS¶
• Prognosis by Stage: ◦ Localized: 44% 5-year survival. ◦ Regional: 16%. ◦ Metastatic: 3.2%. • Complications: ◦ Hypercoagulable states (Trousseau's syndrome). ◦ Malabsorption and weight loss from exocrine insufficiency. ◦ Peritoneal carcinomatosis (Sister Mary Joseph's node).
SPECIAL POPULATIONS¶
• Genetic Screening: ◦ BRCA1/2, PALB2, CDKN2A, STK11 carriers require specific surveillance. • Molecular Profiling: ◦ KRAS wildtype tumors may respond to novel therapies. ◦ Microsatellite instability (MSI) guides immunotherapy eligibility.
KEY PEARLS & HIGH-YIELD POINTS¶
• Trousseau's Syndrome: A critical clinical sign of occult malignancy and hypercoagulability. • CA19-9 Limitation: Not useful in Lewis antigen non-secretors; do not rely solely on it for monitoring in these patients. • Resectability Rule: Surgery is only indicated if the tumor does not involve major vessels (SMA, celiac axis) or has limited involvement of portal veins (<180°). • Neoadjuvant Strategy: Standard for borderline resectable/locally advanced to assess response and downstage.
Reference Tables¶
TABLE 88-1 Germline Mutations, Familial Cancer Syndromes, and Fold Risk of Pancreatic Cancer¶
Harrison's 22e, p.671
| GERMLINE MUTATION | FAMILIAL CANCER SYNDROME |
ESTIMATED INCREASED RISK (FOLD) OF PANCREATIC CANCER |
|---|---|---|
| BRCA2a | Familial breast/ovarian cancer and others |
3.5–10 |
| Familial breast cancer and others |
||
| p16/CDKN2A | Familial atypical multiple mole melanoma (FAMMM) |
15–22 |
| Peutz-Jeghers syndrome | ||
| PRSS1 or SPIN11b | Hereditary (familial) pancreatitis |
53 |
| Ataxia-telangiectasia | ||
| MLH1, MSH2, MSH6, PMS2 |
Heredity nonpolyposis colorectal syndrome or Lynch syndromed |
9–36 |
TABLE 88-2 Definition of Primary Tumor (T) T CATEGORY TX T0 Tis¶
Harrison's 22e, p.675
| T CATEGORY | T CRITERIA | ||
|---|---|---|---|
| TX | Primary tumor cannot be assessed | ||
| Tis | Carcinoma in situ This includes high-grade pancreatic intraepithelial neoplasia (PanIn-3), intraductal papillary mucinous neoplasm with high-grade dysplasia, intraductal tubulopapillary neoplasm with high-grade dysplasia, and mucinous cystic neoplasm with high-grade dysplasia |
||
| T2 | Tumor >2 cm and ≤4 cm in greatest dimension | ||
| T4 | Tumor involves celiac axis, superior mesenteric artery, and/or common hepatic artery, regardless of size | ||
| N CATEGORY | N CRITERIA | ||
| NX | Regional lymph nodes cannot be assessed | ||
| N1 | Metastasis in one to three regional lymph nodes | ||
| M CATEGORY | M CRITERIA | ||
| M0 | No distant metastasis | ||
| AJCC Prognostic Stage Groups | |||
| WHEN T IS… | AND N IS… | AND M IS… | THEN THE STAGE GROUP IS…. |
| Tis | N0 | M0 | 0 |
| N0 | M0 | ||
| T1 | N1 | M0 | IIB |
| N2 | M0 | ||
| T2 | N0 | M0 | IB |
| N1 | M0 | ||
| T2 | N2 | M0 | III |
| N0 | M0 | ||
| T3 | N1 | M0 | IIB |
| N2 | M0 | ||
| T4 | Any N | M0 | III |
| Any N | M1 |
TABLE 88-3 Extent of Disease and Therapeutic Approach¶
Harrison's 22e, p.675
| DESIGNATION (MEDIAN SURVIVAL) | THERAPEUTIC APPROACHES |
|---|---|
| 1. Resectable (localized): (18–23 mo) • No solid tumor contact with celiac axis, hepatic artery, or superior mesenteric artery (SMA), contact with superior mesenteric–portal veins of <180° • Patent superior mesenteric–portal veins • No extrapancreatic disease |
Surgery followed by adjuvant therapy • mFOLFIRINOX or gemcitabine +/– capecitabine or nab-paclitaxel Neoadjuvant chemotherapy followed by surgery |