Diagnostic significance of TCR gene clonal rearrangement analysis in early mycosis fungoides

Abstract

Mycosis fungoides (MF), the most common type of cutaneous T-cell lymphoma, has various unspecific clinical and histological characteristics. Its early diagnosis is challenging. The application of T-cell receptor (TCR) gene clonal rearrangement to the diagnosis of MF has been widely studied. In this study, we used polymerase chain reaction (PCR) to investigate the diagnostic significance of detecting TCR-γ and -β gene clonal rearrangement in the early diagnosis of mycosis fungoides. PCR for TCR-γ and TCR-β gene rearrangement was performed on 19 patients with suspected early MF, 6 with typical MF, and 6 with chronic dermatitis. Of the 19 patients with suspected early MF, 13 had TCR-γ gene clonal rearrangement, whereas none had TCR-β gene clonal rearrangement. All patients with typical MF had TCR gene clonal rearrangement, in which 4 showed TCR-γ clonal rearrangement, 1 showed TCR-β gene clonal rearrangements, and 1 showed both. No patients with chronic dermatitis had TCR gene clonal rearrangement. These results indicate that TCR gene clonal rearrangement analysis is a useful tool in diagnosing early MF. TCR-γ gene is recommended to the routine analysis, whereas TCR-β gene has potential in combination toward intractable cases.

The significance of multiplex PCR/heteroduplex analysis‐based TCR‐γ gene rearrangement combined with laser‐capture microdissection in the diagnosis of early mycosis fungoides

“…In previous studies, clonal TCR ‐γ rearrangement was observed in 73% of cases in plaque stage and in 100% of cases in tumor stage 30,31 . In our analysis, 19 clonality was showed in 71.4% of cases in plaque stage and in 100% of cases in tumor stage by using conventional phenol‐chloroform DNA extraction and multiple PCR/heteroduplex analysis. The percentages obtained in our study were within the range reported by others 10–12,30,31 .…”

“…The TCR ‐γ gene, although typically not expressed on the cell surface, remains rearranged in the T‐cell genome and is a suitable target for amplification mainly because its relatively simple structure requires fewer sets of PCR primers to detect the most common genes. In our previous study, 19 we used six different primer pairs (T VG /T JX , V 2–5 /V 8–12 /JGT 1 , V γ11 /V γ101 /J γ12 , V γ11 /V γ101 /J p12 , BIOMED‐2‐TCR‐γ and BIOMED‐2‐TCR‐β) to detect clonality in classic MF. On the basis of the results, 19 T VG /T JX , V 2–5 /V 8–12 /JGT 1 and BIOMED‐2‐TCR‐γ were selected and utilized in this study.…”

“…In our previous study, 19 we used six different primer pairs (T VG /T JX , V 2–5 /V 8–12 /JGT 1 , V γ11 /V γ101 /J γ12 , V γ11 /V γ101 /J p12 , BIOMED‐2‐TCR‐γ and BIOMED‐2‐TCR‐β) to detect clonality in classic MF. On the basis of the results, 19 T VG /T JX , V 2–5 /V 8–12 /JGT 1 and BIOMED‐2‐TCR‐γ were selected and utilized in this study.…”

“…Clonal rearrangement was detected in all 19 cases, whereas TCR ‐γ and TCR‐β gene rearrangements were detected in 84.2 and 31.6% of the cases, respectively. In particular, a statistically significantly higher clonal rate (78.9%) was detected by using the primer pair V 2–5 /V 8–12 /JGT 1 than by the other primers (47.4% by T VG /T JX , 31.6% by BIOMED‐2‐TCR‐γ and 0% by V γ11 /V γ101 /J γ12 and V γ11 /V γ101 /J p12 ) 19 . Hence, the primer pairs T VG /T JX , V 2–5 /V 8–12 /JGT 1 and BIOMED‐2‐TCR‐γ were utilized in this study.…”

Mycosis Fungoides: Epidemiology in Isfahan, Iran

“…T-cell clonality was present in about 70% (50% -100%) of the biopsies diagnosed as MF [30][31][32][33]; this was 28.5% in a study in Hong Kong [20]. In current study 61.1% of cases showed clonality.…”