Time‐dependent change of T cell receptor clonality: From large plaque parapsoriasis to early mycosis fungoides.

This article discusses the progression of parapsoriasis, a group of diseases that includes pityriasis lichenoides (PL), small-plaque parapsoriasis (SPP), and large-plaque parapsoriasis (LPP), to mycosis fungoides (MF), a type of cutaneous T cell lymphoma (CTCL). While PL rarely progresses to MF, SPP and LPP have occasionally been observed to progress to MF. The article presents a case study of a Japanese man with LPP who eventually developed MF, and analyzes the clonality of T cell receptors (TCRs) in skin samples over time. The study suggests that TCR clonality may be a key factor in differentiating parapsoriasis from MF, but further research is needed to validate these findings. [Extracted from the article]