Lymphomatoid papulosis with folliculotropism, eccrinotropism and neurotropism.

The histopathological characteristics of lymphomatoid papulosis (LyP) vary. Currently, 6 subtypes have been reported, including a new subtype with perifollicular infiltration and different degrees of folliculotropism of CD30+ atypical lymphocytes, known as follicular LyP. However, LyP pathologically manifesting with folliculotropism, eccrinotropism and neurotropism has been rarely reported. We present a case of LyP showing CD30+ atypical lymphocytes around the hair follicle, eccrine gland and nerve fiber, with varying degrees of infiltrates. The pathological characteristics of folliculotropism and eccrinotropism are often associated with mycosis fungoides (MF). This case suggests that differential diagnosis is necessary when atypical lymphocytes infiltrate the follicle and eccrine gland. As folliculotropism and eccrinotropism can occur in both MF and LyP, it may represent a conceptual intersection between the 2 disease processes.