Pancreatic cancer

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Pancreatic cancer
Classification & external resources
ICD-10 C25.
ICD-9 157
OMIM 260350
DiseasesDB 9510
MedlinePlus 000236
eMedicine med/1712 
MeSH D010190

Pancreatic cancer is a malignant tumour within the pancreatic gland. Each year about 32,000 individuals in the United States are diagnosed with this condition, and more than 60,000 in Europe. Depending on the extent of the tumor at the time of diagnosis, the prognosis is generally regarded as poor, with few victims still alive 5 years after diagnosis, and complete remission still extremely rare.

About 95 percent of pancreatic tumors are adenocarcinomas (M8140/3). The remaining 5 percent include other tumors of the exocrine pancreas (e.g. serous cystadenomas), acinar cell cancers, and pancreatic neuroendocrine tumors (such as insulinomas, M8150/1, M8150/3). These tumors have a completely different diagnostic and therapeutic profile, and generally a more favorable prognosis.

Contents

[edit] Signs and symptoms

[edit] Presentation

Early diagnosis of pancreatic cancer is difficult because the symptoms are so non-specific and varied. Common symptoms include abdominal pain, loss of appetite, significant weight loss and painless jaundice. All of these symptoms can be blamed on other causes. Therefore, diagnosis of pancreatic cancer is often late-stage in its development.

Jaundice occurs when the tumour grows and pressure obstructs the common bile duct, which runs partially through the head of the pancreas. Tumours of the head of the pancreas (approximately 60% of cases) will more easily give rise to such symptoms.

Depression has also been associated with pancreatic cancer, sometimes presenting before the cancer is diagnosed. However, the mechanism for this is not known.[1]

[edit] Predisposing factors

Risk factors for pancreatic cancer include:[2]

  • Age
  • Gingivitis or periodontal disease (Dana Farber Cancer Institute of Harvard Medical School study: elevated levels of C-reactive protein, a biomarker for chronic inflammation, and elevated oral bacteria and carcinogenic nitrosamides- which interact with gastric acid-,are found, especially in smokers, in pancreatic cancer cases)
  • Male gender
  • African ethnicity
  • Smoking
  • Diets high in meat
  • Obesity
  • Diabetes
  • Chronic pancreatitis has been linked, but is not known to be causal.
  • Occupational exposure to certain pesticides, dyes, and chemicals related to gasoline
  • Family history
  • Helicobacter pylori infection

[edit] Diagnosis

Courvoisier's law defines the presence of jaundice and a painlessly distended gallbladder as strongly indicative of pancreatic cancer, and may be used to distinguish pancreatic cancer from gallstones.

Pancreatic cancer is usually discovered during the course of the evaluation of aforementioned symptoms. Liver function tests may show a combination of results indicative of bile duct obstruction (raised bilirubin, γ-glutamyl transpeptidase and alkaline phosphatase levels). Ca 19.9 (carbohydrate antigen 19.9) is a tumor marker that is frequently elevated in pancreatic cancer.

Imaging studies, such as ultrasound or abdominal CT may be used to identify tumors. Endoscopic ultrasound (EUS) is another procedure that can help visualize the tumor and obtain tissue to establish the diagnosis.

Ohio State University Medical Center's medical oncology researchers have found that in pancreatic cancer malignancies, the tumor contains markedly higher levels of short molecule strands of certain micro-RNAs (mi-RNA) than does the patient's benign pancreatic tissue or that found in other healthy pancreases. This paves the way for two possibilities: 1) a more early but likely expensive genetic and biochemical molecular screening test profile- which would be an innovation in this cancer; and 2) also possible new, creative and more effective therapies based on the various micro-RNA levels. This opens an exciting new front in confronting a very deadly cancer.

[edit] Treatment

Treatment of pancreatic cancer depends on the stage of the cancer.[3] Recent advances have made resection (surgical removal) of tumors that were previously unresectable due to blood vessel involvement possible. The Whipple procedure is the most common surgical treatment for cancers involving the head of the pancreas. Fluorouracil, gemcitabine, and erlotinib are the chemotherapeutic drug agents of choice.

Stage Description App. % of cases Treatment options Median survival
Local/resectable Disease is confined to the pancreas and is clearly separated from surrounding blood vessels 15 Surgery; postoperative chemotherapy and/or radiation may also be offered 17 months
Locally advanced / unresectable Disease encases or compresses surrounding blood vessels, or has directly extended into adjacent structures 40 Chemotherapy (most commonly gemcitabine-based) and/or radiation. In very rare instances, cancers that respond well to initial treatment may subsequently be surgically resected. 8-9 months
Metastatic Evidence of extrapancreatic spread to distant organs (liver, lungs, etc.) 45 Chemotherapy (most commonly gemcitabine-based); investigational trials 4-6 months

On the back of the results of a Canadian led Phase III Randomised Controlled trial involving 569 patients with advanced pancreatic cancer, the US FDA has licensed the use of erlotinib (Tarceva) in combination with gemcitabine as a palliative agent for this tumour. This trial compared the action of gemcitabine/erlotinib vs gemcitabine/placebo and demonstrated improved survival rates, improved tumour response and improved progression free survival rates. New trials are now investigating the effect of the above combination in the adjuvant and neoadjuvant setting.[4]

In September 2006, it was announced that a new vaccine had been developed to fight pancreatic cancer, with testing on human patients showing promising results.[5][6]

[edit] Prognosis

Patients diagnosed with pancreatic cancer typically have a poor prognosis partly because the cancer usually causes no symptoms early on, leading to metastatic disease at time of diagnosis. Median survival from diagnosis is around 3 to 6 months; 5-year survival is much less than 5%[7] With 32,180 new diagnoses in the United States every year, and 31,800 deaths, mortality approaches 99%, giving pancreatic cancer the #1 fatality rate of all cancers and the #4 cancer killer in the United States amongst both men and women.[8]

Pancreatic cancer occasionally may result in diabetes. Insulin production is hampered and it has been suggested that the cancer can also prompt the onset of diabetes and vice versa.[9]

[edit] Prevention

Prevention of pancreatic cancer consists of avoiding risk factors when possible[10] Cigarette smoking is considered to be the most significant and avoidable risk factor for pancreatic cancer. Maintaining a healthy weight and exercising may be helpful. Additionally, increasing consumption of fruits, vegetables, and whole grains while decreasing red meat intake is recommended by the American Cancer Society.

The relationship of overall fruit and vegetable consumption with pancreatic cancer has been questioned by several research groups.[11][12] In 2006 a large prospective cohort study of over 80,000 subjects failed to prove a definite association.[13] The evidence in support of this lies mostly in small case-control studies.

In September 2006, a long-term study concluded that taking Vitamin D can substantially cut the risk of pancreatic cancer (as well as other cancers) by up to 50%.[14][15][16] More studies of this have been called for.

[edit] Awareness

  • November is Pancreatic Cancer Awareness Month
  • Purple is the traditional color chosen to represent pancreatic cancer
  • An estimated 52.7 million dollars was spent on pancreatic cancer research in 2004 of the National Cancer Institute’s (NCI) cancer research budget. This is just 1% of the NCI’s 4.824 billion dollar cancer research budget for 2004.[17]
  • Despite the especially lethal nature of pancreatic cancer, the research spending per pancreatic cancer patient is only $1145, the lowest of any leading cancer.[18]
  • For a list of celebrities who have succumbed to this disease, see Category:Pancreatic cancer deaths
  • The Pancreatic Cancer Action Network (PanCAN) was created as an advocacy group for pancreatic cancer.
  • The national charity Pancreatic Cancer UK works to raise awareness in the UK

[edit] External links

[edit] References

  1. ^ Carney CP, Jones L, Woolson RF, Noyes R Jr, Doebbeling BN. Relationship between depression and pancreatic cancer in the general population. Psychosom Med 2003;65:884-8. PMID 14508036.
  2. ^ http://www.cancer.org/docroot/CRI/content/CRI_2_4_2X_What_are_the_risk_factors_for_pancreatic_cancer_34.asp?sitearea=
  3. ^ http://www.cancersupportivecare.com/pancreas.html#stage
  4. ^ FDA approval briefing
  5. ^ http://abclocal.go.com/kgo/story?section=edell&id=4605575
  6. ^ http://abclocal.go.com/kgo/story?section=edell&id=4605594
  7. ^ http://www.who.int/tobacco/research/cancer/en/
  8. ^ http://pancan.org/About/pancreaticCancerStats.html
  9. ^ http://www.molecular-cancer.com/content/2/1/4
  10. ^ http://www.cancer.org/docroot/CRI/content/CRI_2_4_2X_Can_pancreatic_cancer_be_prevented_34.asp?rnav=cri
  11. ^ Coughlin, SS; Calle EE, Patel AV, Thun MJ. (2000 Dec). "Predictors of pancreatic cancer mortality among a large cohort of United States adults.". Cancer Causes Control. 11 (10): 915-23.. PMID 11142526. Retrieved on 2007-02-27. 
  12. ^ Zheng, W; et al (1993 Sep). "A cohort study of smoking, alcohol consumption, and dietary factors for pancreatic cancer (United States).". Cancer Causes Control. 4 (5): 477-82.. PMID 8218880. Retrieved on 2007-02-27. 
  13. ^ Larsson, Susanna; Niclas Håkansson, Ingmar Näslund, Leif Bergkvist and Alicja Wolk (February 2006). "Fruit and vegetable consumption in relation to pancreatic cancer risk: a prospective study.". Cancer Epidemiology Biomarkers & Prevention 15: 301-305. PMID 16492919. Retrieved on 2007-02-27. 
  14. ^ http://news.bbc.co.uk/1/hi/health/5334534.stm
  15. ^ http://www.webmd.com/content/article/127/116673.htm
  16. ^ http://www.forbes.com/forbeslife/health/feeds/hscout/2006/09/14/hscout534925.html
  17. ^ http://pancan.org/About/pancreaticCancerStats.html
  18. ^ http://pancan.org/About/pancreaticCancerStats.html