[Modern molecular biology diagnosis of malignant cutaneous lymphomas].

The diagnosis of cutaneous malignant lymphoma is based on clinical, histo-morphological and immunochemical findings and, now a days, on molecular biology analyses of the genotype in the lymphocytic infiltrate. By using the polymerase chain reaction (PCR) with specific primers for the Ig heavy chain gene and the T-cell receptor gamma chain gene, the detection of monoclonal cell populations in the skin infiltrate is possible. Since this method produces results within 3 days, since paraffin-embedded skin and lymph node biopsies and heparinized peripheral blood can be used and since no radioactivity is necessary, this technique has important advantages over traditional techniques such as Southern blot analyses. In addition, specific PCR analyses may allow a patient-specific monitoring during therapy and also may detect early relapses of the lymphoproliferative malignant disease.