DETECTION OF CLONAL T-CELL RECEPTOR-GAMMA CHAIN GENE REARRANGEMENTS BY POLYMERASE-CHAIN-REACTION AND DENATURING GRADIENT GEL-ELECTROPHORESIS (PCR DGGE) IN ARCHIVAL SPECIMENS FROM PATIENTS WITH EARLY CUTANEOUS T-CELL LYMPHOMA - CORRELATION OF HISTOLOGIC-FINDINGS WITH PCR/DGGE/

Background: Early stages of cutaneous T-cell lymphoma (CTCL) may be di fficult to distinguish from benign inflammatory dermatoses by routine histologic examination. Objective: Our purpose was to determine whethe r clonal rearrangements of the T-cell receptor (TCR) gamma gene by pol ymerase chain reaction and denaturing gradient gel electrophoresis (PC R/DGGE) could be detected in the early stages of CTCL and to correlate these findings with conventional histopathology. Methods: A total of 39 specimens from 12 patients with CTCL were obtained. The slides were evaluated independently by three dermatopathologists, and categorized into three groups: nondiagnostic, suggestive of CTCL, and diagnostic of CTCL. Of the 39 specimens, 33 were tested by PCR/DGGE by means of G C-clamped primers for clonal rearrangement of the TCR gamma gene. Resu lts: The histologic evaluation of the 12 cases showed a significant va riation among the three dermatopathologists. The correlation of PCR/DG GE with routine histology was as follows: Clonal TCR gamma gene rearra ngements were demonstrated in 73% of the specimens nondiagnostic for C TCL, 71% of those suggestive of CTCL, and 74% of those diagnostic of C TCL. Conclusion: Clonal TCR gamma gene rearrangements may be detected in patients with early CTCL, even when the histologic findings are not unequivocally diagnostic. In patients with multiple biopsy specimens, identical clones were demonstrated in all rearranged samples, indicat ing the same neoplastic clone was present in the earliest stages of di sease.