A 40+ year-old male presents for a severely itchy rash located on his face and right arm. This first started in 2018 and a biopsy was done at that time with a diagnosis of subacute spongiotic dermatitis. PAS was negative for fungi.
Over the years, he has been on several courses of oral and topical steroids with the rash clearing after a few weeks. Every winter this rash recurs, and in the past year it has been in different locations, including the face. Allergy tests, bloodwork, CT, and ultrasound have come back normal.
Physical exam shows large eczematous patches on the trunk and leonine facies on the face. Two punch biopsies were taken: left superior lateral midback and right central forehead. T-cell labs were taken in addition to CBC with Auto Diff, Hepatic function 2000 panel, and LDH isoenzymes.
Which differential diagnoses should be considered?
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Dermatitis, CTCL, and Hansen’s disease
1. Site A (Left Superior Lateral Midback):
The epidermis demonstrates mild spongiosis and focal hyperkeratosis. There is noted a superficial band-like infiltrate with some epidermotropism. The lymphocytes present are small to intermediate in size with hyperconvoluted nuclei. There is also reticular fibroplasia noted in the superficial papillary dermis. PAS and Fite stains were negative for fungal and lepromatous organisms respectively in these sections. Immunohistochemical stains reveal a predominant T cell (CD3) infiltrate with a few scattered B cells (CD20). The CD4:CD8 ratio of the T cell infiltrate is increased at 7:1. CD5 staining is retained whereas a CD30 stain is negative in these sections.
2. Site B (Right Central Forehead):
The histologic findings and immunohistochemical staining patterns essentially mirrored those described above, however, additional features of small atypical infiltrative lymphocytes into a degenerating hair follicle associated with mucin deposition (“follicular mucinosis”) was also noted. The classic features of mycosis fungoides in concert with features of follicular mucinosis is also termed: “alopecia mucinosa.”
Cutaneous T cell lymphoma (CTCL) is a term that encompasses a broad group of helper T cell lymphomas, and are among the most common adult lymphomas. They present in the skin, but later can involve blood and other organ systems. Mycosis fungoides, the most common form of CTCL, most often occurs in late adulthood. It is categorized as patch, plaque, or tumor stages clinically. Early stage CTCL diagnosis can be elusive, often requiring several biopsies performed over the course of years in order for histologic confirmation.
The patient presented with a 2 year history of an eczema diagnosis and had been treated as such, which is often the case for early stage disease. Much less common is an acceleration to tumor stage disease as seen in this patient who presented with the classic leonine facies of tumor stage disease. Our patient had also experienced a 20+ lb weight loss over the last 2 years, which he had attributed to minor dietary changes he had made.
Patient was prescribed Pramosone 2.5% lotion BID for itch relief and was referred to a CTCL clinic at local university for further serologies, work up and systemic therapy.
By: Dr. John Soderberg, MD and Dr. John Pujals, MD