What information about the genetics of the cells might be included in the pathology report?


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Cytogenetics uses tissue culture and specialized techniques to provide genetic information about cells, particularly genetic alterations. Some genetic alterations are markers or indicators of a specific cancer. For example, the Philadelphia chromosome is associated with chronic myelogenous leukemia (CML). Some alterations can provide information about prognosis, which helps the doctor make treatment recommendations (3). Some tests that might be performed on a tissue sample include:

• Fluorescence in situ hybridization (FISH): Determines the positions of particular genes. It can be used to identify chromosomal abnormalities and to map genes.

• Polymerase chain reaction (PCR): A method of making many copies of particular DNA sequences of relevance to the diagnosis.

• Real-time PCR or quantitative PCR: A method of measuring how many copies of a particular DNA sequence are present.

• Reverse-transcriptase polymerase chain reaction (RT-PCR): A method of making many copies of a specific RNA sequence.

• Southern blot hybridization: Detects specific DNA fragments.

• Western blot hybridization: Identifies and analyzes proteins or peptides.

Can individuals get a second opinion about their pathology results?

Although most cancers can be easily diagnosed, sometimes patients or their doctors may want to get a second opinion about the pathology results (1). Patients interested in getting a second opinion should talk with their doctor. They will need to obtain the slides and/or paraffin block from the pathologist who examined the sample or from the hospital where the biopsy or surgery was done.

Many institutions provide second opinions on pathology specimens. NCI-designated cancer centers or academic institutions are reasonable places to consider. Patients should contact the facility in advance to determine if this service is available, the cost, and shipping instructions.

What research is being done to improve the diagnosis of cancer?

NCI, a component of the National Institutes of Health, is sponsoring clinical trials that are designed to improve the accuracy and specificity of cancer diagnoses. Before any new method can be recommended for general use, doctors conduct clinical trials to find out whether it is safe and effective.

People interested in taking part in a clinical trial should talk with their doctor. Information about clinical trials is available from NCI’s Cancer Information Service (CIS) at 1–800–4–CANCER and on NCI’s clinical trials page.

Selected References

1. Morra M, Potts E. Choices. 4th ed. New York: HarperResource, 2003.

2. Borowitz M, Westra W, Cooley LD, et al. Pathology and laboratory medicine. In: Abeloff MD, Armitage JO, Niederhuber JE, Kastan MB, McKenna WG, editors. Clinical Oncology. 3rd ed. London: Churchill Livingstone, 2004.

3. Connolly JL, Schnitt SJ, Wang HH, et al. Principles of cancer pathology. In: Bast RC Jr., Kufe DW, Pollock RE, et al., editors. Cancer Medicine. 6th ed. Hamilton, Ontario, Canada: BC Decker Inc., 2003.

Source: National Cancer Institute.