About a year ago appeared incredible information about 15-years-old Jack Andraka, an American high school student, who devised a test which detects pancreatic cancer in the early stage. The test is based on nanotechnologies, namely it uses carbon nanotubes. According to the author it is by 90% more accurate, significantly quicker and is about to cost 3 cents.
On the basis of the analysis of internet database containing info about proteins present in pancreatic cancer, Jack especially valued mesothelin on the basis of which the test works. (1) The protein is also characteristic for adenocarcinoma of lungs, ovarium and biliary tracts. Present CA 19-9 marker, which is used in pancreatic cancers diagnostics, is increased by about 80% in the later stages of the disease, and similarly as mesothelin it is not characteristic for pancreas (stomach, liver, large bowel, gall bladder, lungs),nor typical only for neoplastic process. It may be increased in pancreatitis, pneumonia, cystic fibrosis and hepatocirrhosis.
The most often pancreatic cancer is adenocarcinoma (about 90-95%). It is insidious cancer which is mostly asymptomatic in the early stages of the disease. The symptoms appear when it is very advanced. As in the case of other neoplastic diseases they are typical: weight loss, vomiting, Trousseau syndrome, nausea. There are also symptoms specific for pancreas such as jaundice, pain or/and palpable tumor in the upper abdomen, diabetes. There are groups of increased risk of pancreatic cancer occurence to which belong people with BRCA2 and PALB2 genes mutations, with Peutz–Jeghers and Lynch syndrome and also smokers or people with diabetes, obese, abusing alcohol. In these groups of patients cheap and easily accessible test would be especially helpful.
Survival prognoses are non-optimistic. Generally, it is assumed that 25% of the patients have a chance to survive a year, 6% lives 5 years. In the case of focal changes the survival rate is about 15% and in the case of advanced tumour with metastases the patients survive for 6-10 months. (2,3) Better prognoses are for neuroendocrine pancreatic tumours which were not previously diagnosed. That is why the patients may live with missed adenocarcinoma diagnosis even long time after the treatment. They may have different symptoms which are more connected with their hormonal functions (hypoglycemia in insulinoma, diabetes in glukagonoma). The symptoms appear earlier what despite the tumour’s malignancy increases chances for survival.
Andrak’s test consists in the use of paper soaked in a liquid containing carbon nanotubes. The nanotubes bind mesothelin and the result of the test may be read after 5 minutes (1). The teenager described his procedure in 32 pages long document. The draft was sent to over 200 professors of John Hopkins University and only one of the professors, Anirban Maitra, had agreed to continue research in his laboratory. In the future, the author would like to use similar test in order to detect ovary and lung cancers, Alzheimer’s disease, HIV and AIDS. The teenager won the Intel competition for young scientists because of the interesting discovery. He has an international patent on his test although the project is at the early laboratory stage. There was no research on humans.
One may remain skeptical and not influenced by the euphoria caused by the new invention which was published in the same year when the teenager was given a prize. American scientists examined 151 people (15 healthy, 52 with benign non-pancreatic cancer, 33 with benign pancreatic cancer, 9 with cholangioma and 42 with pancreatic adenocarcinoma). They measured mesothelin level with the use of Mesomark test (sensitivity less than 10 ng/ml) and megakaryocyte potentiating factor (MPF) using Human MPF ELISA. (4) According to this publication the increased mesothelin concentration is not pathogonomic for the neoplastic process. In about 50% of healthy people mesothelin level is 80 ng/ml or higher. In a lot of patients in different stages of the pancreatic cancer increased mesothelin level is not observed. Its concentration does not correspond to the stage of the tumour’s advancement. (4) We may remain unexcited with the outstanding news which is broadcasted by all of the media. We should still look for effective cancer diagnostic methods. As it turns out it is difficult to make groundbreaking discovery without basic knowledge in the researched field.
Written by: Magdalena Chorążka
Source:
1. For A World Without Cancer: Jack Andraka at TEDxOrangeCoast
2. American Cancer Society: Cancer Facts & Figures 2010: see page 4 for incidence estimates, and page 19 for survival percentages”.
3. Benson AB, Myerson RJ, and Sasson AR. Pancreatic, Neuroendocrine GI, and Adrenal Cancers. Cancer Management 13th edition.http://www.cancernetwork.com/cancer-management/pancreatic/article/10165/1802606 “What You Need To Know About Cancer of the Pancreas — National
4. Sharon E, Zhang J, Hollevoet K, Steinberg SM, Pastan I, Onda M, Gaedcke J, Ghadimi BM, Ried T, Hassan R (April 2012). “Serum mesothelin and megakaryocyte potentiating factor in pancreatic and biliary cancers”. Clin. Chem. Lab. Med. 50 (4): 721–5.
Would you like to know more? Watch on MEDtube.net: Pancreatic cancer – endoultrasonography (EUS) with biopsy
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Pancreatic cancer – breakthrough in diagnostics?
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