Stomach cancer

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Stomach cancer
Classification and external resources
Adenocarcinoma of the stomach.jpg
A suspicious stomach ulcer that was ultimately diagnosed as cancer on biopsy and resected. The surgical specimen was subsequently kept for educational purposes.
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Stomach cancer
Classification and external resources
Adenocarcinoma of the stomach.jpg
A suspicious stomach ulcer that was ultimately diagnosed as cancer on biopsy and resected. The surgical specimen was subsequently kept for educational purposes.

Stomach cancer, or gastric cancer, refers to cancer arising from any part of the stomach. Stomach cancer causes over 700,000 deaths worldwide per year.[1] Prognosis is poor with a less than 10% 5-year survival rate, largely because most people with the condition present with advanced disease.[2]

Signs and symptoms[edit]

Endoscopic image of linitis plastica, a type of stomach cancer where the entire stomach is invaded, leading to a leather bottle-like appearance with blood coming out of it.
Endoscopic images of the stomach cancer in early stage. Its histology was poorly differentiated adenocarcinoma with signet ring cells.Left above=Normal, right above=FICE, left low=acetate stained, right low= AIM stained

Stomach cancer is often either asymptomatic (producing no noticeable symptoms) or it may cause only nonspecific symptoms (symptoms which are not specific to just stomach cancer, but also to other related or unrelated disorders) in its early stages. By the time symptoms occur, the cancer has often reached an advanced stage (see below) and may have also metastasized (spread to other, perhaps distant, parts of the body), which is one of the main reasons for its relatively poor prognosis.[3] Stomach cancer can cause the following signs and symptoms:

Stage 1 (Early)[edit]

Stage 2 (Middle)[edit]

Stage 3 (Late)[edit]

Note that these can be symptoms of other problems such as a stomach virus, gastric ulcer or tropical sprue.


Helicobacter pylori infection is the main risk factor in 65–80% of gastric cancers, but in only 2% of such infections.[5][6] The mechanism by which H. pylori induces stomach cancer potentially involves chronic inflammation, or the action of H. pylori virulence factors such as CagA.[7]

Smoking increases the risk of developing gastric cancer significantly, from 40% increased risk for current smokers to 82% increase for heavy smokers. Gastric cancers due to smoking mostly occur in the upper part of the stomach near the esophagus.[8][9][10] Some studies show increased risk with alcohol consumption as well.[6][11]

Dietary factors are not proven causes,[12] but some foods including smoked foods,[13] salt and salt-rich foods, red meat, processed meat, pickled vegetables,[6] and bracken[14] are associated with a higher risk of stomach cancer. Nitrates and nitrites in cured meats can be converted by certain bacteria, including H. pylori, into compounds that have been found to cause stomach cancer in animals. On the other hand, fresh fruit and vegetable intake, citrus fruit intake, and antioxidant intake are associated with a lower risk of stomach cancer.[6][8] A Mediterranean diet is also associated with lower rates of stomach cancer,[15] as is regular aspirin use.[6]

There is a correlation between iodine deficiency and gastric cancer.[16][17][18]

Sequence of 123-iodine human scintiscans after an intravenous injection, (from left) after 30 minutes, 20 hours, and 48 hours. A high and rapid concentration of radio-iodine is evident in gastric mucosa of the stomach, in salivary glands, oral mucosa and in the periencephalic and cerebrospinal fluid (left). In the thyroid gland, I-concentration is more progressive, also in the reservoir (from 1% after 30 minutes, to 5.8 % after 48 hours, of the total injected dose.[19]

Gastric cancer shows a male predominance in its incidence as up to three males are affected for every female. Estrogen may protect women against the development of this cancer form.[20]

Approximately 10% of cases show a genetic component.[21] The International Cancer Genome Consortium is leading efforts to identify genomic changes involved in stomach cancer.[22][23] A very small percentage of diffuse-type gastric cancers (see Histopathology below) arise from an inherited abnormal CDH1 gene. Hereditary diffuse gastric cancer (HDGC) has recently been identified and research is ongoing. Genetic testing and treatment options are already available for families at risk.[24]

Other factors associated with increased risk are AIDS,[6] diabetes,[25] pernicious anemia,[11] chronic atrophic gastritis,[26] Menetrier's disease (hyperplastic, hypersecretory gastropathy),[27] and intestinal metaplasia.[28]


To find the cause of symptoms, the doctor asks about the patient's medical history, does a physical exam, and may order laboratory studies. The patient may also have one or all of the following exams:

In 2013, Chinese and Israeli scientists reported a successful pilot study of a breathalyzer-style breath test intended to diagnose stomach cancer by analyzing exhaled chemicals without the need for an intrusive endoscopy. A larger-scale clinical trial is now underway.[30]

Abnormal tissue seen in a gastroscope examination will be biopsied by the surgeon or gastroenterologist. This tissue is then sent to a pathologist for histological examination under a microscope to check for the presence of cancerous cells. A biopsy, with subsequent histological analysis, is the only sure way to confirm the presence of cancer cells.[11]

Various gastroscopic modalities have been developed to increase yield of detected mucosa with a dye that accentuates the cell structure and can identify areas of dysplasia. Endocytoscopy involves ultra-high magnification to visualize cellular structure to better determine areas of dysplasia. Other gastroscopic modalities such as optical coherence tomography are also being tested investigationally for similar applications.[31]

A number of cutaneous conditions are associated with gastric cancer. A condition of darkened hyperplasia of the skin, frequently of the axilla and groin, known as acanthosis nigricans, is associated with intra-abdominal cancers such as gastric cancer. Other cutaneous manifestations of gastric cancer include tripe palms (a similar darkening hyperplasia of the skin of the palms) and the Leser-Trelat sign, which is the rapid development of skin lesions known as seborrheic keratoses.[32]

Various blood tests may be done, including: Complete Blood Count (CBC) to check for anemia. Also, a stool test may be performed to check for blood in the stool.


Poor to moderately differentiated adenocarcinoma of the stomach. H&E stain.
Gastric signet ring cell carcinoma. H&E stain.
Adenocarcinoma of the stomach and intestinal metaplasia. H&E stain.


If cancer cells are found in the tissue sample, the next step is to stage, or find out the extent of the disease. Various tests determine whether the cancer has spread and, if so, what parts of the body are affected. Because stomach cancer can spread to the liver, the pancreas, and other organs near the stomach as well as to the lungs, the doctor may order a CT scan, a PET scan, an endoscopic ultrasound exam, or other tests to check these areas. Blood tests for tumor markers, such as carcinoembryonic antigen (CEA) and carbohydrate antigen (CA) may be ordered, as their levels correlate to extent of metastasis, especially to the liver, and the cure rate.

Staging may not be complete until after surgery. The surgeon removes nearby lymph nodes and possibly samples of tissue from other areas in the abdomen for examination by a pathologist.

The clinical stages of stomach cancer are:[35][36]

The TNM staging system is also used.[37]

In a study of open-access endoscopy in Scotland, patients were diagnosed 7% in Stage I 17% in Stage II, and 28% in Stage III.[38] A Minnesota population was diagnosed 10% in Stage I, 13% in Stage II, and 18% in Stage III.[39] However in a high-risk population in the Valdivia Province of southern Chile, only 5% of patients were diagnosed in the first two stages and 10% in stage III.[40]


Cancer of the stomach is difficult to cure unless it is found at an early stage (before it has begun to spread). Unfortunately, because early stomach cancer causes few symptoms, the disease is usually advanced when the diagnosis is made.[41] Treatment for stomach cancer may include surgery,[42] chemotherapy, and/or radiation therapy.[43] New treatment approaches such as biological therapy and improved ways of using current methods are being studied in clinical trials.[44]


Surgery remains the only curative therapy for stomach cancer.[2] Of the different surgical techniques, endoscopic mucosal resection (EMR) is a treatment for early gastric cancer (tumor only involves the mucosa) that has been pioneered in Japan, but is also available in the United States at some centers.[2] In this procedure, the tumor, together with the inner lining of stomach (mucosa), is removed from the wall of the stomach using an electrical wire loop through the endoscope. The advantage is that it is a much smaller operation than removing the stomach.[2] Endoscopic submucosal dissection (ESD) is a similar technique pioneered in Japan, used to resect a large area of mucosa in one piece.[2] If the pathologic examination of the resected specimen shows incomplete resection or deep invasion by tumor, the patient would need a formal stomach resection.[2]

Those with metastatic disease at the time of presentation may receive palliative surgery and while it remains controversial, due to the possibility of complications from the surgery itself and the fact that it may delay chemotherapy the data so far is mostly positive, with improved survival rates being seen in those treated with this approach.[2][45]


The use of chemotherapy to treat stomach cancer has no firmly established standard of care. Unfortunately, stomach cancer has not been particularly sensitive to these drugs, and chemotherapy, if used, has usually served to palliatively reduce the size of the tumor, relieve symptoms of the disease and increase survival time. Some drugs used in stomach cancer treatment have included: 5-FU (fluorouracil) or its analog capecitabine, BCNU (carmustine), methyl-CCNU (semustine) and doxorubicin (Adriamycin), as well as mitomycin C, and more recently cisplatin and taxotere, often using drugs in various combinations. The relative benefits of these different drugs, alone and in combination, are unclear.[46] Clinical researchers have explored the benefits of giving chemotherapy before surgery to shrink the tumor, or as adjuvant therapy after surgery to destroy remaining cancer cells.[2] Recently, a targeted treatment called trastuzumab has become available for the treatment of those with a HER2 mutation in their tumor cells.[2]


Radiation therapy (also called radiotherapy) may also be used to treat stomach cancer, often as an adjuvant to chemotherapy and/or surgery.[2]


The prognosis of stomach cancer is generally poor, due to the fact the tumour has often metastasised by the time of discovery and the fact that most people with the condition are elderly (median age is between 70 and 75 years) at presentation.[47] The 5-year survival rate for stomach cancer is reported to be less than 10%.[2]


Age-standardized death from stomach cancer per 100,000 inhabitants in 2004.[48]
  no data

Stomach cancer is the fourth most common cancer worldwide with 930,000 cases diagnosed in 2002.[49] It is more common in men and in developing countries.[49][50] In 2012 number of deaths were 700,000 having decreased slightly from 774,000 in 1990 making it the third leading cause of cancer death after lung cancer and liver cancer.[51][52]

Out of 10 million people in the Czech Republic, 3 new cases of stomach cancer in people under 30 years of age in 1999 were diagnosed.[53] Other studies show that less than 5% of stomach cancers occur in people under 40 years of age with 81.1% of that 5% in the age-group of 30 to 39 and 18.9% in the age-group of 20 to 29.[54]

In 2011, stomach cancer accounted for 0.64% of deaths (13,230 cases) in the United States,[55] but this figure was higher in other countries. In the same year in China, for example, stomach cancer accounted for 3.99% of all deaths (354,829 cases).[56] The mortality rate was highest in the Maldives, stomach cancer accounting for 8.92% of all deaths.[57]

Other animals[edit]

The stomach is a muscular organ of the gastrointestinal tract that holds food and begins the digestive process by secreting gastric juice. The most common cancers of the stomach are adenocarcinomas but other histological types have been reported. Signs vary but may include vomiting (especially if blood is present), weight loss, anemia, and lack of appetite. Bowel movements may be dark and tarry in nature. In order to determine whether cancer is present in the stomach, special X-rays and/or abdominal ultrasound may be performed. Gastroscopy, a test using an instrument called endoscope to examine the stomach, is a useful diagnostic tool that can also take samples of the suspected mass for histopathological analysis to confirm or rule out cancer. The most definitive method of cancer diagnosis is through open surgical biopsy.[58] Most stomach tumors are malignant with evidence of spread to lymph nodes or liver, making treatment difficult. Except for lymphoma, surgery is the most frequent treatment option for stomach cancers but it is associated with significant risks.


  1. ^ "Cancer (Fact sheet N°297)". World Health Organization. February 2014. Retrieved 2009-05-11. 
  2. ^ a b c d e f g h i j k Orditura, M; Galizia, G; Sforza, V; Gambardella, V; Fabozzi, A; Laterza, MM; Andreozzi, F; Ventriglia, J; Savastano, B; Mabilia, A; Lieto, E; Ciardiello, F; De Vita, F (February 2014). "Treatment of gastric cancer." (PDF). World Journal of Gastroenterology 20 (7): 1635–1649. doi:10.3748/wjg.v20.i7.1635. PMC 3930964. PMID 24587643. 
  3. ^ "Statistics and outlook for stomach cancer". Cancer Research UK. Retrieved 19 February 2014. 
  4. ^ "Guidance on Commissioning Cancer Services Improving Outcomes in Upper Gastro-intestinal Cancers". NHS. Jan 2001. 
  5. ^ "Proceedings of the fourth Global Vaccine Research Forum". Initiative for Vaccine Research team of the Department of Immunization, Vaccines and Biologicals. WHO. April 2004. Retrieved 2009-05-11. "Epidemiology of Helicobacter pylori and gastric cancer…" 
  6. ^ a b c d e f González CA, Sala N, Rokkas T (2013). "Gastric cancer: epidemiologic aspects". Helicobacter 18 (Supplement 1): 34–38. doi:10.1111/hel.12082. PMID 24011243. 
  7. ^ Hatakeyama, M. & Higashi, H (2005). "Helicobacter pylori CagA: a new paradigm for bacterial carcinogenesis". Cancer Science 96 (12): 835–843. doi:10.1111/j.1349-7006.2005.00130.x. PMID 16367902. 
  8. ^ a b "What Are The Risk Factors For Stomach Cancer(Website)". American Cancer Society. Retrieved 2010-03-31. 
  9. ^ Nomura A, Grove JS, Stemmermann GN, Severson RK (1990). "Cigarette smoking and stomach cancer.". Cancer Research 50 (21): 7084. PMID 2208177. 
  10. ^ Trédaniel J, Boffetta P, Buiatti E, Saracci R, Hirsch A (August 1997). "Tobacco smoking and gastric cancer: Review and meta-analysis". International Journal of Cancer 72 (4): 565–73. doi:10.1002/(SICI)1097-0215(19970807)72:4<565::AID-IJC3>3.0.CO;2-O. PMID 9259392. 
  11. ^ a b c d Thrumurthy SG, Chaudry MA, Hochhauser D, Ferrier K, Mughal M (2013). "The diagnosis and management of gastric cancer". British Medical Journal 347: f6367. doi:10.1136/bmj.f6367. PMID 24291271. 
  12. ^ Tumors of the GI Tract at Merck Manual of Diagnosis and Therapy Professional Edition
  13. ^ Jakszyn P, González CA (2006). "Nitrosamine and related food intake and gastric and oesophageal cancer risk: A systematic review of the epidemiological evidence". World J Gastroenterol 12 (27): 4296–4303. PMID 16865769. 
  14. ^ Alonso-Amelot ME, Avendaño M (March 2002). "Human carcinogenesis and bracken fern: a review of the evidence". Current Medicinal Chemistry 9 (6): 675–86. doi:10.2174/0929867023370743. PMID 11945131. 
  15. ^ Buckland G, Agudo A, Lujan L, Jakszyn P, Bueno-De-Mesquita HB, Palli D, Boeing H, Carneiro F, Krogh V (2009). "Adherence to a Mediterranean diet and risk of gastric adenocarcinoma within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort study". American Journal of Clinical Nutrition 91 (2): 381–90. doi:10.3945/ajcn.2009.28209. PMID 20007304. 
  16. ^ Josefssson, M.; Ekblad, E. (2009). "22. Sodium Iodide Symporter (NIS) in Gastric Mucosa: Gastric Iodide Secretion". In Preedy, Victor R.; Burrow, Gerard N.; Watson, Ronald. Comprehensive Handbook of Iodine: Nutritional, Biochemical, Pathological and Therapeutic Aspects. Elsevier. pp. 215–220. ISBN 978-0-12-374135-6. 
  17. ^ Venturi, Sebastiano (2011). "Evolutionary Significance of Iodine". Current Chemical Biology- (3): 155–162 (8). doi:10.2174/187231311796765012. ISSN 1872-3136. 
  18. ^ Venturi II, S.; Donati, F.M.; Venturi, A.; Venturi, M.; (2000). Role of iodine in evolution and carcinogenesis of thyroid, breast and stomach.= Adv Clin Path. 4 (4). pp. 11–17. PMC 2452979. PMID 10936894. 
  19. ^ Venturi, S.; Donati, F.M.; Venturi, A.; Venturi, M. (2000). "Environmental Iodine Deficiency: A Challenge to the Evolution of Terrestrial Life?". Thyroid 10 (8): 727–9. doi:10.1089/10507250050137851. PMID 11014322. 
  20. ^ Chandanos, Evangelos (December 2007). Estrogen in the development of esophageal and gastric adenocarcinoma (PDF) (Doctoral thesis). Karolinska Institutet. ISBN 978-91-7357-370-2. 
  21. ^ Lee H-J, Yang H-K, Ahn Y-O (2002). "Gastric cancer in Korea". Gastric Cancer 5 (3): 177–82. doi:10.1007/s101200200031. PMID 12378346. 
  22. ^ "Gastric Cancer - Adenocarcinoma". International Cancer Genome Consortium. Retrieved 24 February 2014. 
  23. ^ "Gastric Cancer - Intestinal- and diffuse-type". International Cancer Genome Consortium. Retrieved 24 February 2014. 
  24. ^ Brooks-Wilson AR, Kaurah P, Suriano G, Leach S, Senz J, Grehan N, Butterfield YS, Jeyes J, Schinas J (2004). "Germline E-cadherin mutations in hereditary diffuse gastric cancer: assessment of 42 new families and review of genetic screening criteria". Journal of Medical Genetics 41 (7): 508–17. doi:10.1136/jmg.2004.018275. PMC 1735838. PMID 15235021. 
  25. ^ Tseng C-H, Tseng F-H (2014). "Diabetes and gastric cancer: The potential links". World J Gastroenterol 20 (7): 1701–1711. doi:10.3748/wjg.v20.i7.1701. PMC 3930970. PMID 24587649. 
  26. ^ Crosby DA, Donohoe CL, Fitzgerald L, Muldoon C, Hayes B, O’Toole D, Reynolds JV (2004). "Gastric Neuroendocrine Tumours". Digestive Surgery 29 (4): 331–348. doi:10.1159/000342988. PMID 23075625. 
  27. ^ Kim J, Cheong JH, Chen J, Hyung WJ, Choi SH, Noh SH (2004). "Menetrier's Disease in Korea: Report of Two Cases and Review of Cases in a Gastric Cancer Prevalent Region". Yonsei Medical Journal 45 (3): 555–560. PMID 15227748. 
  28. ^ Tsukamoto T, Mizoshita T, Tatematsu M (2006). "Gastric-and-intestinal mixed-type intestinal metaplasia: aberrant expression of transcription factors and stem cell intestinalization". Gastric cancer 9 (3): 156–166. doi:10.1007/s10120-006-0375-6. PMID 16952033. 
  29. ^ Virmani, V; Khandelwal, A; Sethi, V; Fraser-Hill, M; Fasih, N; Kielar, A (2012). "Neoplastic stomach lesions and their mimickers: Spectrum of imaging manifestations". Cancer imaging : the official publication of the International Cancer Imaging Society 12: 269–78. doi:10.1102/1470-7330.2012.0031. PMID 22935192. 
  30. ^ "Breath Test Could Detect And Diagnose Stomach Cancer". Medical News Today. 6 March 2013. Retrieved 8 March 2013. 
  31. ^ Inoue H, Kudo S-, Shiokawa A (2005). "Technology Insight: laser-scanning confocal microscopy and endocytoscopy for cellular observation of the gastrointestinal tract". Nature Clinical Practice Gastroenterology & Hepatology 2 (1): 31–7. doi:10.1038/ncpgasthep0072. PMID 16265098. 
  32. ^ Pentenero M, Carrozzo M, Pagano M, Gandolfo S (2004). "Oral acanthosis nigricans, tripe palms and sign of leser-trelat in a patient with gastric adenocarcinoma". International Journal of Dermatology 43 (7): 530–2. doi:10.1111/j.1365-4632.2004.02159.x. PMID 15230897. 
  33. ^ Kumar; et al. (2010). Pathologic Basis of Disease (8th ed.). Saunders Elsevier. p. 784. ISBN 978-1-4160-3121-5. 
  34. ^ Kumar 2010, p. 786
  35. ^ "Detailed Guide: Stomach Cancer Treatment Choices by Type and Stage of Stomach Cancer". American Cancer Society. 2009-11-03. 
  36. ^ Guy Slowik (October 2009). "What Are The Stages Of Stomach Cancer?". 
  37. ^ "Detailed Guide: Stomach Cancer: How Is Stomach Cancer Staged?". American Cancer Society. 
  38. ^ Paterson HM, McCole D, Auld CD (2006). "Impact of open-access endoscopy on detection of early oesophageal and gastric cancer 1994–2003: population-based study". Endoscopy 38 (5): 503–7. doi:10.1055/s-2006-925124. PMID 16767587. 
  39. ^ Crane SJ, Locke GR, Harmsen WS, Zinsmeister AR, Romero Y, Talley NJ (2008). "Survival Trends in Patients With Gastric and Esophageal Adenocarcinomas: A Population-Based Study". Mayo Clinic Proceedings 83 (10): 1087–1094. doi:10.4065/83.10.1087. PMC 2597541. PMID 18828967. 
  40. ^ Heise K, Bertran E, Andia ME, Ferreccio C (2009). "Incidence and survival of stomach cancer in a high-risk population of Chile". World Journal of Gastroenterology 15 (15): 1854–1862. doi:10.3748/wjg.15.1854. PMC 2670413. PMID 19370783. 
  41. ^ Roopma Wadhwa, Takashi Taketa, Kazuki Sudo, Mariela A. Blum, Jaffer A. Ajani (2013). "Modern Oncological Approaches to Gastric Adenocarcinoma". Gastroenterology Clinics of North America 42 (2): 359–369. doi:10.1016/j.gtc.2013.01.011. PMID 23639645. 
  42. ^ Ke Chen, Xiao-Wu Xu, Ren-Chao Zhang, Yu Pan, Di Wu, Yi-Ping Mou (2013). "Systematic review and meta-analysis of laparoscopy-assisted and open total gastrectomy for gastric cancer". World J Gastroenterol 19 (32): 5365–5376. doi:10.3748/wjg.v19.i32.5365. PMID 23983442. 
  43. ^ Jennifer L. Pretz, Jennifer Y. Wo, Harvey J. Mamon, Lisa A. Kachnic, Theodore S. Hong (2011). Chemoradiation Therapy: Localized Esophageal, Gastric, and Pancreatic Cancer 22 (3). pp. 511–524. doi:10.1016/j.soc.2013.02.005. PMID 23622077. 
  44. ^ Judith Meza-Junco, Heather-Jane Au, Michael B Sawyer (2011). "Critical appraisal of trastuzumab in treatment of advanced stomach cancer". Cancer Management and Research 2011 (3): 57–64. doi:10.2147/CMAR.S12698. PMID 21556317. 
  45. ^ Sun, J; Song, Y; Wang, Z; Chen, X; Gao, P; Xu, Y; Zhou, B; Xu, H (December 2013). "Clinical significance of palliative gastrectomy on the survival of patients with incurable advanced gastric cancer: a systematic review and meta-analysis." (PDF). BMC cancer 13: 577. doi:10.1186/1471-2407-13-577. PMID 24304886. 
  46. ^ Scartozzi M, Galizia E, Verdecchia L, Berardi R, Antognoli S, Chiorrini S, Cascinu S (2007). "Chemotherapy for advanced gastric cancer: across the years for a standard of care". Expert Opinion on Pharmacotherapy 8 (6): 797–808. doi:10.1517/14656566.8.6.797. PMID 17425475. 
  47. ^ Cabebe, EC; Mehta, VK; Fisher, G, Jr (21 January 2014). "Gastric Cancer". In Talavera, F; Movsas, M; McKenna, R; Harris, JE. Medscape Reference. WebMD. Retrieved 4 April 2014. 
  48. ^ "WHO Disease and injury country estimates". World Health Organization. 2009. Retrieved Nov 11, 2009. 
  49. ^ a b Parkin DM, Bray F, Ferlay J, Pisani P (2005). "Global Cancer Statistics, 2002". CA: A Cancer Journal for Clinicians 55 (2): 74–108. doi:10.3322/canjclin.55.2.74. PMID 15761078. 
  50. ^ "Are the number of cancer cases increasing or decreasing in the world?". WHO Online Q&A. WHO. 1 April 2008. Retrieved 2009-05-11. 
  51. ^ Lozano, R (15 December 2012). "Global and regional mortality from 235 causes of death for 20 age groups in 1990 and 2010: a systematic analysis for the Global Burden of Disease Study 2010". Lancet 380 (9859): 2095–128. doi:10.1016/S0140-6736(12)61728-0. PMID 23245604. 
  52. ^ "PRESS RELEASE N° 224 Global battle against cancer won’t be won with treatment alone Effective prevention measures urgently needed to prevent cancer crisis". World Health Organization. 3 February 2014. Retrieved 14 March 2014. 
  53. ^ Simsa J, Leffler J, Hoch J, Linke Z, Pádr R (2004). "Gastric cancer in young patients—is there any hope for them?". Acta Chirurgica Belgica 104 (6): 673–6. PMID 15663273. 
  54. ^ "Gastric Cancer in Young Adults". Revista Brasileira de Cancerologia 46 (3). Jul 2000. 
  55. ^ "Health profile: United States". Le Duc Media. Retrieved 13 March 2014. 
  56. ^ "Health profile: China". Le Duc Media. Retrieved 13 March 2014. 
  57. ^ "Health profile: Maldives". Le Duc Media. Retrieved 13 March 2014. 
  58. ^ Withrow SJ, MacEwen EG, ed. (2001). Small Animal Clinical Oncology (3rd ed.). W.B. Saunders Company. 

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