Molecular Diagnostics

Molecular Oncology

Section Chief: Joseph D. Locker, MD, PhD

The Molecular Oncology Laboratory provides comprehensive nucleic acid-based tests for the diagnosis and management of neoplasia. Specimens are most often submitted for gene studies of leukemia and lymphoma and molecular markers of residual neoplastic disease.

Select this link for information regarding specific tests performed by the Molecular Oncology Laboratory, including a full list of tests, consultation contacts, and details for specimen preparation and delivery.

See below for more general information about the techniques used by the Molecular Oncology Laboratory.

Southern blot and quantitative dot blot hybridization systems and PCR-based amplification systems provide a level of sensitivity unequaled by routine histopathological analysis, flow cytometry, or karyotypic analysis. For example, detection of neoplastic cells constituting as few as 1 % of the cells in a specimen is frequently attainable by Southern blot analysis. Further, one neoplastic cell in a background of 10,000 normal cells routinely can be detected in PCR-based studies.

The value of these sensitive techniques in clinical practice is illustrated in the following settings:

*Studies of B-cell immunoglobulin and T-cell receptor gene rearrangements often provide evidence of clonality in an atypical B lymphoid infiltrate when other methods fail.
*A chromosomal translocation detected at the initial presentation of a leukemia patient may be used as a marker for that individual's disease. PCR-based testing for the translocation marker provides the most sensitive means for monitoring the patient during and after treatment.
*Follicular lymphoma is usually associated with a t(14;18) translocation. PCR analysis of this translocation is the most sensitive test available for detecting bone marrow involvement and for guiding therapeutic decisions, which are often based upon the presence or absence of disseminated disease.
*Neuroblastoma is the most common tumor of early childhood. Aggressive combined modality therapy is warranted by the discovery of increased numbers of copies of the N-myc gene. Quantitative blot analysis can be used to discriminate between chromosome 2 aneuploidy and N-myc gene amplification, an indicator of poor prognosis.

Professional consultation concerning appropriate testing for individual patients is available by contacting Joseph Locker, MD, PhD, at (412) 648-8253 or Jeffery Kant, MD, PhD, at (412) 648-8519.
(For more information about the tests performed by the Molecular Oncology Laboratory, please click here.)

The test(s) is (are) performed under an agreement with Roche Molecular Systems, Inc.