Background: The Lichenoid tissue reaction (LTR) is present in a variet
y of dermatoses. Numerous histologic variants of mycosis fungoides (MF
) have also been described. Objective: Our purpose was to analyze a su
bset of patients with mycosis fungoides (MF) who had a prominent LTR a
t the time of presentation. Methods: Clinical and pathologic features
were evaluated in 12 patients with MF and an LTR. Results: The primary
complaint was intense pruritus (in 10 of 12 patients). An accelerated
course was noted in one half of the patients including four with Seza
ry syndrome. Four patients died: two with Sezary syndrome and two with
extensive patch/plaque MF. Lymphocyte atypia, prominent basal cell la
yer epidermotropism, and the presence of plasma cells and eosinophils
may help to distinguish lichenoid MF from Lichen planus. Conclusion: A
subset of patients with MF present with Lichenoid changes. The pathol
ogic features may have a striking resemblance to lichen planus. Our fi
ndings suggest that lichenoid changes in MF tend to be associated with
intense pruritus and may connote a poor prognosis.