PANCREATIC CANCER


I. Epidemiology and risk factors for pancreatic cancer

  1. Tobacco abuse
  2. Alcohol abuse
  3. Chronic pancreatitis
  4. Longstanding diabetes mellitus
  5. Family history (in general; also there is a rare autosomal dominant form with 50% lifetime risk of pancreatic Ca in carriers)
  6. Peutz-Jeghers syndrome, hereditary nonpolyposis colon Ca (Lynch syndrome), ataxic telangiectasias
  7. History of partial gastrectomy or cholecystectomy
  8. Blood group O is a negative risk factor (RR 0.6-0.7)s
  9. Male:female 1.3:1
  10. Mean age at diagnosis is 72y; 87% of cases are diagnosed at 55y or older

II. Diagnosis and prognosis of pancreatic cancer

  1. Symptoms are generally related to the anatomic site of the Ca (75% of tumors are in the pancreatic head with symptoms of obstructive jaundice, anorexia, and weight loss)
  2. Tissue diagnosis (e.g. by endoscopic-guided fine-needle aspiration) is not always feasible and in some cases of suspected pancreatic Ca a decision whether or not to perform a pancreatic resection may need to be made without the benefit of a tissue diagnosis.
  3. In a prospective study in 150 pts undergoing surgery for suspected pancreatic Ca, multivariate analysis showed that the following had 100% specificity for an eventual diagnosis of pancreatic Ca (regardless of imaging results): weight loss of > 20 pounds, serum bilirubin > 3 mg/dL, and CA 19-9 level > 37U/mL (Am. J. Surg. 191:191, 2006--JW)
  4. Mean survival if metastatic at time of diagnosis is 4-6mos

III. Staging of pancreatic cancer (preoperatively):

  1. Endoscopic ultrasound is superior to standard CT for detection and local staging, but CT may be superior for detecting hepatic and distant metastases as well as vascular involvement, though with multidetector CT this gap may not be significant.  Also, both modalities may miss some lesions.
  2. Staging schema:

IV. Treatment of pancreatic cancer

  1. Surgery
    1. May be an option if no distant metastases or involvement of the superior mesenteric vein, portal vein, superia mesenteric artery, inferior vena cava, aorta, or celiac axis
    2. Only about 20% of patients are surgical candidates
    3. "Whipple" procedure is the most common surgical treatment (distal gastrectomy with removal of pancreatic head, duodenum, first 15cm of jejunum, common bile duct, and gallbladder)
    4. 5-year survival after Whipple is 20% without adjuvant chemotherapy (see below), 30% with
  2. Anti-androgens for tx of pancreatic cancer: 49 pts with pancreastic Ca randomized to flutamide vs. placebo; 1y survival rates were 50% with flutamide and 5% with placebo (BMJ 316:1935, 1998--JW)
  3. Adjuvant chemotherapy after surgical resection of pancreatic cancer:
    1. In a study of 289 pts s/p complete macroscopic resection of pancreatic adenocarcinoma randomized to post-op chemo, chemo-radiotherapy, both, or neither, after median 47mos, composite analysis of both chemoradiotherapy groups vs. the pts who didn't receive chemoradiotherapy showed sig. shorter median survival (16mos vs. 18mos) in the former; composite analysis of chemotherapy vs. non-chemotherapy groups showed sig. greater median survival (20mos vs. 15.5mos) in the former (European Study Group for Pancreatic Cancer study, NEJM 350:1200, 2004--JW)
  4. Patients with non-operable disease are often treated with chemotherapy and/or radiation therapy
  5. Severe retroperitoneal pain not adequately managed with opiate analgesics can be treated with alcohol ablation of the celiac plexus
  6. Anorexia/weight loss can improve with megestrol acetate (Megace) and pancreatic enzymes to improve fat absorption.
  7. Progress is often followed with CA 19-9 (low specificity so not useful as a diagnostic or screening tool; never elevated in patients who lack Lewis blood group antigens)
(Sources include Core Content Review of Family Medicine, 2012)