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Indeterminate cell histiocytosis successfully treated with ultraviolet B phototherapy
M Ishibashi1, T Ouchi, A Tanikawa
1Department of Dermatology, Keio University School of Medicine, Tokyo, Japan. ishibashi@saichu.jp
Insights
Indeterminate cell histiocytosis (ICH) is a rare skin disorder. Broadband ultraviolet B (UVB) phototherapy showed significant effectiveness in treating skin lesions associated with ICH.
Area of Science:
- Dermatology
- Oncology
- Histiocytosis
Background:
- Indeterminate cell histiocytosis (ICH) is a rare neoplastic disorder.
- Characterized by skin infiltration of neoplastic cells positive for S-100 and CD1a.
- ICH cells typically lack Birbeck's granules.
Observation:
- A 75-year-old male presented with a 4-year history of multiple skin papules.
- Skin biopsy confirmed dense infiltration of histiocytic cells (CD1a+/S100+).
- No systemic abnormalities were detected via CT, gallium scintigraphy, or abdominal sonography.
Findings:
- Broadband ultraviolet B (UVB) therapy was administered for the skin lesions.
- UVB treatment resulted in partial to almost complete remission of ICH skin lesions.
- This case highlights a potential therapeutic option for ICH.
Implications:
- Broadband ultraviolet B (UVB) phototherapy may be a viable treatment for Indeterminate cell histiocytosis.
- Further research into phototherapy for rare histiocytic disorders is warranted.
- This finding could offer a less invasive treatment approach for ICH patients.
Abstract:
Indeterminate cell histiocytosis (ICH) is a rare disorder, characterized by infiltration of the skin by neoplastic cells that are characteristically positive for S-100 and CD1a, but lack Birbeck's granules. A 75-year-old man presented with a 4-year history of multiple papules on the trunk, limbs, face and neck. Skin biopsy revealed dense infiltration of histiocytic cells that were CD1a+/S100+, but lacked Birbeck's granules. No other abnormality was seen during a general examination including a computed tomography scan of the body, gallium scintigraphy, and an abdominal sonography. Broadband ultraviolet B (UVB) treatment was used for the skin lesions, and partial but almost complete remission was obtained. The case suggests that UVB phototherapy is an option for treatment of ICH.
