Cytogenetics in oncology: From hematologic malignancies to solid tumors

Although presently known as an environmentally-related disease and appears mostly sporadic, cancer is regarded as a genetic disease based on the presence of genetic mutation as a consistent factor. The “Philadelphia Chromosome” found consistently among chronic myeloid leukemia (CML) patients was the first significant finding of a chromosomal abnormality specifically related to a particular disease. Starting from this point, cytogenetics as the study of chromosomes has become a valuable tool in the assessment of cancer – as an aid in diagnosis, thus guiding therapy, and as a prognostic marker. Chromosomal abnormalities are found mostly in hematological malignancies and the findings are more pathognomonic. The situation is different in solid tumors, which when visible to the naked eye already have complex chromosomal changes and thus pose technical difficulties to the cytogeneticist. However, the scientists believe that the shift in chromosomal studies from conventional cytogenetics to molecular cytogenetics will provide further information regarding solid tumors. (Med J Indones 2009; 18: 69-75)