Vesicular Mycosis Fungoides.

Area of Science:

• Dermatology
• Oncology
• Pathology

Background:

• Mycosis fungoides (MF) is the most common type of cutaneous T-cell lymphoma.
• Less common MF variants can mimic reactive skin conditions, posing diagnostic challenges.
• Chronic antigen stimulation is hypothesized to drive T-cell migration to the skin in MF.

Observation:

• Four patients with a longstanding eruption were identified.
• Vesiculation was a prominent histological feature in all cases, leading to initial misdiagnosis.
• Two cases showed aggressive clinical progression with extracutaneous dissemination.

Findings:

• Histological clues included basilar cerebriform lymphocyte colonization and mucinous vesicles.
• Phenotypic and molecular profiles confirmed MF diagnosis.
• A T-helper type 2-dominant cytokine profile (IL-5, IL-10) was observed in atypical lymphocytes.

Implications:

• Vesicular MF represents a distinct histological and potentially clinical variant of MF.
• The presence of vesicles may correlate with a more aggressive clinical course and advanced disease.
• Understanding the T-helper type 2 cytokine milieu is crucial for managing advanced MF.