DNA ploidy in diagnosis
In DNA ploidy analyses, the DNA content per nucleus is calculated for all the nuclei from a tumor specimen to yield a histogram of the distribution of DNA content in the measured sample. This is an objective measure of large-scale genomic instability which discriminates between specimen with a normal DNA content and nuclei with an abnormal and often unstable DNA content.
DNA ploidy has been shown in multiple studies to be a diagnostic and prognostic marker for patients with several different cancer types, and in particular for patients with gynaecological cancers. By performing DNA ploidy analyses on tumor material, one can therefore obtain valuable information that can contribute in the process of determining the best treatment scheme for each patient.
At Oslo University Hospital, the Institute for Cancer genetics and Informatics has established DNA ploidy analysis as a method for diagnostic and prognostic assessment in clinical activity within gynaecological cancer and to some extent cancer of the prostate. On average, 750 cancer samples per year have been analyzed for DNA ploidy since we introduced our automated system in 2003. This method assists clinicians in making the appropriate judgment for which treatment plan to choose. For example, a young woman with early stage ovarian cancer may have her tumor sampled for DNA ploidy. If the tumor is classified as diploid and less aggressive, she can choose to bear a child before having her ovaries surgically removed. A patient with an aggressive prognosis as defined by an aneuploid classification would require immediate intervention.Our DNA ploidy laboratory processes tumor samples within a maximum of five working days.
We also have on-going studies on large retrospective series of several different cancers, such as rectal and colon cancer, where the results are very promising. We thus expect an increase in the annual number of DNA ploidy analyses that will be performed by the institute in the coming years.
For more information about the DNA ploidy project, click here.