Pancreatic cancer is a deadly disease with a case fatality of 95%, and it is one of the few cancers whose incidence is actually increasing annually, i.e. 0.5% per year. The reason the case fatality is high is because symptoms do not appear until very late when the cancer has already spread beyond the pancreas and sometimes to distal sites. This increase appears similar in low, middle and high income countries, and it is everyone’s responsibility to find a test that can diagnose this deadly disease earlier, so pancreatic cancer can be surgically removed at earlier and more curable stages. The CA19.9, a type of antigen released by pancreatic cancer cells is presently used to diagnose pancreatic cancer but is highly inaccurate. A comparison of CA19.9 diagnosed and autopsy confirmed patients was made. Of the 10,000 included in this study, 300 had pancreatic cancer and of these 300, 130 had pancreatic cancer and the test also found them to have the disease. But another 20 who did not have pancreatic cancer were also found by this CA19.9 to have pancreatic cancer.

a) Construct a 2 x 2 table. (Upload a picture/document with table)

b) What is the prevalence of pancreatic cancer in this population?

c) What is the sensitivity of CA19.9? What does this mean?

d) What is the specificity of CA19.9? What does this mean?

e)What is the positive predictive value? Explain what this number means.

f) What is the negative predictive value? How would you interpret it?

g) Should this test be recommended for widespread use?

 

Answer rating: 100% (QA)

a Pancreatic Cancer Positive Negative Total CA199 test Positive 130 TP 20 FP 150 Negative 170 FN 968... View the full answer