Pancreatic cancer

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

Pancreatic cancer is a malignant tumor of the pancreas. Each year about 37,680 individuals in the United States are diagnosed with this condition, and 34,290 die from the disease. In Europe more than 60,000 are diagnosed each year. Depending on the extent of the tumor at the time of diagnosis, the prognosis is generally regarded as poor, with <5% of those diagnosed still alive five years after diagnosis, and complete remission still extremely rare.[1] 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.[1]

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 pain in the upper abdomen that typically radiates to the back and is relieved by leaning forward (seen in carcinoma of the body or tail of the pancreas), loss of appetite, significant weight loss and painless jaundice related to bile duct obstruction (carcinoma of the head of the pancreas). All of these symptoms can have multiple other causes. Therefore, pancreatic cancer is often not diagnosed until it is advanced.

Jaundice occurs when the tumor grows and obstructs the common bile duct, which runs partially through the head of the pancreas. Tumors of the head of the pancreas (approximately 60% of cases) are more likely to cause jaundice by this mechanism.

Trousseau sign, in which blood clots form spontaneously in the portal blood vessels, the deep veins of the extremities, or the superficial veins anywhere on the body, is sometimes associated with pancreatic cancer.

Clinical depression has been reported in association with pancreatic cancer, sometimes presenting before the cancer is diagnosed. However, the mechanism for this association is not known.[2]

[edit] Predisposing factors

Risk factors for pancreatic cancer include:[3]

[edit] Diagnosis

History — Most patients with pancreatic cancer experience pain, weight loss, or jaundice.[10]

Pain is present in 80 to 85 percent of patients with locally advanced or advanced metastic disease. The pain is usually felt in the upper abdomen as a dull ache that radiates straight through to the back. It may be intermittent and made worse by eating. Weight loss can be profound; it may be associated with anorexia, early satiety, diarrhea, or steatorrhea. Jaundice is often accompanied by pruritus and dark urine. Painful jaundice is present in approximately one-half of patients with locally unresectable disease, while painless jaundice is present in approximately one-half of patients with a potentially resectable and curable lesion. The initial presentation varies according to tumor location. Tumors in the pancreatic body or tail usually present with pain and weight loss, while those in the head of the gland typically present with steatorrhea, weight loss, and jaundice. The recent onset of atypical diabetes mellitus, a history of recent but unexplained thrombophlebitis, or a previous attack of pancreatitis are sometimes noted.

Courvoisier sign 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 conjugated bilirubin, γ-glutamyl transpeptidase and alkaline phosphatase levels). CA19-9 (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.

[edit] Treatment

[edit] Surgery

Treatment of pancreatic cancer depends on the stage of the cancer.[11] The Whipple procedure is the most common surgical treatment for cancers involving the head of the pancreas. It can only be performed if the patient is likely to survive major surgery, and if the tumor is localised without invading local structures or metastasizing. It can therefore only be performed in the minority of cases. Recent advances have made possible resection (surgical removal) of tumors that were previously unresectable due to blood vessel involvement.[citation needed] Tumors of the tail of the pancreas can be resected using a procedure known as a distal pancreatectomy [2], and recently localized tumors of the pancreas have been resected using minimally invasive (laproscopic) approaches.

After surgery, adjuvant chemotherapy with gemcitabine may be offered to eliminate whatever tumor tissue may remain in the body. This has been shown to increase 5-year survival rates. Addition of radiation therapy is a hotly debated topic, with groups in the US often favoring the use of adjuvant radiation therapy, while groups in Europe do not.[12]

Surgery may be performed for palliation, if the tumor is invading or compressing the duodenum or colon. In that case, bypass surgery may overcome the obstruction and improve quality of life, but it is not intended as a cure.

[edit] Chemotherapy

In patients not suitable for resection with curative intent, palliative chemotherapy may be used to improve quality of life and gain a modest survival benefit. Gemcitabine was approved by the US FDA in 1998 after a clinical trial reported improvements in quality of life in patients with advanced pancreatic cancer. This marked the first FDA approval of a chemotherapy drug for a non-survival clinical trial endpoint. Gemcitabine is administered intravenously on a weekly basis. Addition of oxaliplatin (Gem/Ox) conferred benefit in small trials, but is not yet standard therapy.[13] Fluorouracil (5FU) may also be included.

On the basis 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 regimen for pancreatic cancer. This trial compared the action of gemcitabine/erlotinib vs gemcitabine/placebo and demonstrated improved survival rates, improved tumor response and improved progression-free survival rates. The survival improvement with the combination is on the order of less than four weeks, leading some cancer experts to question the incremental value of adding erlotinib to gemcitabine treatment. New trials are now investigating the effect of the above combination in the adjuvant and neoadjuvant setting.[14] A trial of anti-angiogenesis agent bevacizumab (Avastin) as an addition to chemotherapy has shown no improvement in survival of patients with advanced pancreatic cancer. It may cause higher rates of high blood pressure, bleeding in the stomach and intestine, and intestinal perforations.


[edit] Prognosis

Patients diagnosed with pancreatic cancer typically have a poor prognosis partly because the cancer usually causes no symptoms early on, leading to locally advanced or metastatic disease at time of diagnosis. Median survival from diagnosis is around 3 to 6 months; 5-year survival is much less than 5%.[15] With 37,170 cases diagnosed in the United States in 2007, and 33,700 deaths, pancreatic cancer has one of the highest fatality rates of all cancers and is the fourth highest cancer killer in the United States among both men and women. Although it accounts for only 2.5% of new cases, pancreatic cancer is responsible for 6% of cancer deaths each year.[16]

Pancreatic cancer may occasionally 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.[17] Thus diabetes is both a risk factor for the development of pancreatic cancer and diabetes can be an early sign of the disease in the elderly.

[edit] Prevention

According to the American Cancer Society, there are no established guidelines for preventing pancreatic cancer, although cigarette smoking is responsible for 20-30% of pancreatic cancers.[18]

The ACS recommends keeping a healthy weight, and increasing consumption of fruits, vegetables, and whole grains while decreasing red meat intake, although there is no consistent evidence that this will prevent or reduce pancratic cancer specifically.[19][20] In 2006 a large prospective cohort study of over 80,000 subjects failed to prove a definite association.[21] 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%.[22][23][24] More studies of this have been called for.

Several studies, including one published June 1, 2007, indicate that B vitamins such as B12, B6, and folate, can reduce the risk of pancreatic cancer when consumed in food, but not when ingested in vitamin tablet form.[25][26] It would be, however, premature at this point in time to consume vitamins specifically with the hope of preventing pancreatic cancer.

[edit] Awareness

  • November is Pancreatic Cancer Awareness Month
  • Purple is the traditional color chosen to represent pancreatic cancer awareness.
  • The National Cancer Institute’s cancer research budget was $4.824 billion in 2004, an estimated $52.7 million of which was devoted to pancreatic cancer.[27]
  • Research spending per pancreatic cancer patient is $1145, the lowest of any leading cancer.[28]
  • For a list of celebrities who have succumbed to this disease, see Category:Pancreatic cancer deaths. For a list of survivors see Category:Pancreatic cancer survivors.
  • The Pancreatic Cancer Action Network (PanCAN) was created as an advocacy group for pancreatic cancer.

[edit] References

  1. ^ a b c Ghaneh P, Costello E, Neoptolemos JP (2007). "Biology and management of pancreatic cancer". Gut 56 (8): 1134-52. doi:10.1136/gut.2006.103333. PMID 17625148. 
  2. ^ 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.
  3. ^ ACS :: What Are the Risk Factors for Cancer of the Pancreas?. Retrieved on 2007-12-13.
  4. ^ What You Need To Know About Cancer of the Pancreas - National Cancer Institute. Retrieved on 2007-12-22.
  5. ^ Iodice S, Gandini S, Maisonneuve P, Lowenfels AB (2008). "Tobacco and the risk of pancreatic cancer: a review and meta-analysis". Langenbecks Arch Surg. doi:10.1007/s00423-007-0266-2. PMID 18193270. 
  6. ^ Red Meat May Be Linked to Pancreatic Cancer. Journal of the National Cancer Institute. WebMD (2005-10-05). Retrieved on 2008-03-05.
  7. ^ Obesity Linked to Pancreatic Cancer. American Cancer Society. Cancer Epidemiology, Biomarkers & Prevention (Vol. 14, No. 2: 459-466) (2005-03-06). Retrieved on 2008-03-05.
  8. ^ Efthimiou E, Crnogorac-Jurcevic T, Lemoine NR, Brentnall TA (Feb 2001). "Inherited predisposition to pancreatic cancer". Gut 48 (2): 143-7. doi:10.1136/gut.48.2.143. PMID 11156628. 
  9. ^ Michaud DS, Joshipura K, Giovannucci E, Fuchs CS (2007). "A prospective study of periodontal disease and pancreatic cancer in US male health professionals". J. Natl. Cancer Inst. 99 (2): 171-5. doi:10.1093/jnci/djk021. PMID 17228001. 
  10. ^ Bakkevold KE, Arnesjø B, Kambestad B (1992). "Carcinoma of the pancreas and papilla of Vater: presenting symptoms, signs, and diagnosis related to stage and tumour site. A prospective multicentre trial in 472 patients. Norwegian Pancreatic Cancer Trial". Scand. J. Gastroenterol. 27 (4): 317-25. doi:10.3109/00365529209000081. PMID 1589710. 
  11. ^ [1]
  12. ^ Neoptolemos JP, Stocken DD, Friess H, et al (2004). "A randomized trial of chemoradiotherapy and chemotherapy after resection of pancreatic cancer". N. Engl. J. Med. 350 (12): 1200-10. doi:10.1056/NEJMoa032295. PMID 15028824. 
  13. ^ Demols A, Peeters M, Polus M, et al (2006). "Gemcitabine and oxaliplatin (GEMOX) in gemcitabine refractory advanced pancreatic adenocarcinoma: a phase II study". Br. J. Cancer 94 (4): 481-5. doi:10.1038/sj.bjc.6602966. PMID 16434988. 
  14. ^ FDA approval briefing
  15. ^ WHO | Cancer
  16. ^ Cancer Statistics, 2007 - Jemal et al. 57 (1): 43 - CA: A Cancer Journal for Clinicians
  17. ^ Molecular Cancer | Full text | The relationship between diabetes and pancreatic cancer
  18. ^ ACS :: Can Cancer of the Pancreas be Prevented?. Retrieved on 2007-12-13.
  19. ^ 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. 
  20. ^ 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. 
  21. ^ 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. 
  22. ^ BBC NEWS | Health | Vitamin D 'slashes cancer risk'
  23. ^ Vitamin D May Cut Pancreatic Cancer
  24. ^ http://www.forbes.com/forbeslife/health/feeds/hscout/2006/09/14/hscout534925.html
  25. ^ Plasma Folate, Vitamin B6, Vitamin B12, and Homocysteine and Pancreatic Cancer Risk in Four Large Cohorts -- Schernhammer et al. 67 (11): 5553 -- Cancer Research. Retrieved on 2007-06-04.
  26. ^ United Press International - Consumer Health Daily - Briefing. Retrieved on 2007-06-04.
  27. ^ PanCAN - Working Together for a Cure™
  28. ^ PanCAN - Working Together for a Cure™

[edit] External links