You two break me up...you both can be so funny...and goodness knows, we need humor when it comes to talking the subject of BC...so busy I haven't much time for reviewing the forum...gee whiz, I miss you two, Zach and Holly the most. Keep up the good work. Hugs, Melodie
Melodie, Indy Pouch, U.W.Medical Center, Seattle, Dr. Paul H. Lange & Jonathan L. Wright
12 years 4 months ago - 12 years 4 months ago#20574by wsilberstein
Sensitivity and specificity:
If a test is sensitive It will find most of the positives. Using bladder cancer as an example, a sensitive test will not miss many bladder cancers - but if the test is not specific (low specificity) it will have a lot of false positives, meaning a lot of patients will require further evaluation because the screening test suggsted they might have bladder cancer even though it turns out they don't.
Testing for blood in the urine is a fairly sensitive test since the vast majority of patients with bladder cancer have blood in the urine, however the specificity is very low since there are many other reasons a person could test positve for blood in the urine. The standard cytology has shown a low sensitivity for low grade cancers, but doesn't have many false positives so it has high specificity.
Unfortunately the most senstive test usually have the lowest specificity, while the most accurate tests (regarding spcificity) might miss too many patients. The goal is to find a screening test that will not miss many bladder cancers, but which will not have a high number a false positives.
Did I make it clear? If I try to say any more I'll trip over my tongue:P
TaG3 + CIS 12/2000. TURB + Mitomycin C (No BCG)
Urethral stricture, urethroplasty 10/2009
CIS 11/2010 treated with BCG. CIS 5/2012 treated with BCG/interferon
T1G3 1/2013. Radical Cystectomy 3/5/2013, No invasive cancer. CIS in right ureter.
Incontinent. AUS implant 2/2014. AUS explant 5/2014