Mayo Test Catalog, (Sorted By Test Name) - Mayo Medical ...

ZAP70
83727
9864
NEZPP
Immunoblot
Reference Values:
Yersinia enterocolitica, IgA by Immunoblot Negative
Yersinia enterocolitica, IgG by Immunoblot Negative
Yersinia enterocolitica, IgM by Immunoblot Negative
Test Performed by: ARUP Laboratories
500 Chipeta Way
Salt Lake City, UT 84108
ZAP-70, Chronic Lymphocytic Leukemia (CLL) Prognosis
Clinical Information: B-cell chronic lymphocytic leukemia (CLL) is the most common leukemia in
adults. Its clinical course is highly variable with survival times ranging from months to decades. The
standard procedure for estimating prognosis is clinical staging systems developed by Rai and Binet. In
these staging systems, most CLL patients have early-stage disease. Genetic prognostic markers such as
immunoglobulin heavy chain gene mutational status and FISH studies for specific chromosomal
abnormalities have now been developed to refine the risk of progressive disease. CD38 and ZAP-70 have
been identified as surrogate markers for mutation status and can be evaluated by flow cytometric
immunophenotyping. ZAP-70 (70-kDa zeta-associated protein) is an intracellular tyrosine kinase
discovered initially because of its role in T-cell signaling. It has also been found to be associated with the
B-cell receptor in CLL. The expression of ZAP-70 (>20% of B cells) has been associated with an
increased risk for an adverse outcome in B-cell CLL and is considered an important risk factor in these
patients. ZAP-70 expression, if present, is constant throughout the patient's clinical course and thus is a
valid risk marker regardless of when it is evaluated.
Useful For: A risk factor for disease progression in patients with B-cell chronic lymphocytic leukemia
Interpretation: ZAP-70 expression is considered to be a risk factor for disease progression in patients
with B cell chronic lymphocytic leukemia (CLL). The threshold for ZAP70 staining is established by
using normal B cells as the negative cutoff value and comparing with background positive T-cell staining.
-ZAP-70-negative (20% of monoclonal B cells) CLL patients have a median time to treatment of
2.9 years. See ZAP70 Expression and Overall Survival Among Patients with B-Cell CLL in Multimedia
for survival curves.
Reference Values:
An interpretive report will be provided.
Clinical References: 1. Rassenti LZ, Huynh L, Toy TL, et al: ZAP-70 compared with
immunoglobulin heavy-chain gene mutation status as a predictor of disease progression in chronic
lymphocytic leukemia. N Engl J Med 2004 August 26;351(9):893-901 2. Crespo M, Bosch F, Villamor N,
et al: ZAP-70 expression as a surrogate for immunoglobulin-variable-region mutations in chronic
lymphocytic leukemia. N Engl J Med 2003 May 1;348(18):1764-1765 3. Orchard JA, Ibbotson RE, Davis
Z, et al: ZAP-70 expression and prognosis in chronic lymphocytic leukaemia. Lancet 2004 January
10;363(9403):105-111
Ziehl-Nielsen Stain for Acid- Fast Bacteria
Useful For: For acid-fast inclusion bodies
Reference Values:
The laboratory will provide a pathology consultation and stained slide.
Zinc Protoporphyrin, Blood
Current 300009 as of January 3, 2013 2:22 pm CST 800-533-1710 or 507-266-5700 or MayoMedicalLaboratories.com Page 1912