Urticaria pigmentosa localized on radiation field

ARTICLE

Auteur(s) : Christelle COMTE, Didier BESSIS, Olivier DEREURE, Bernard GUILLOT

Department of Dermatology, Hôpital Saint-Eloi, 80 Avenue A. Fliche, CHU Montpellier, F 34295 Montpellier Cedex 5, France

Article accepted on 05/05/2003

Urticaria pigmentosa (UP) is the most common form of cutaneous mastocytosis. The pathomechanism of this disease is poorly understood. We herein report on a case of UP arising on a radiation field for breast carcinoma.

Case report

A 39-year-old woman was referred to our institution for non-pruritic lesions of 4 years duration mainly localized on the right breast. These elements consisted in red-brownish macules of three to five millimeters in diameter, located on the right breast, the right arm and the dorsal aspect of the chest, more particularly around the scar of a surgical flap performed two years ago for breast reconstruction but without involvement of the flap itself (Fig. 1). Darier’s sign was negative. Her medical history was remarkable for a right breast adenocarcinoma with lymph node involvement (T2N1M0) treated in November 1996 with chemotherapy (doxorubicine, cyclophosphamide and 5FU), followed by surgery, hormonal therapy with LH-RH analogue and tamoxifen and prophylactic radiotherapy (45 grays) on the right breast, the inner mammary nodes and the right supra-clavicular area. In December 1997, the patient received a mammary prothesis of the Mac Ghan type but the prothesis became painful and was removed in March 1999, replaced by a breast reconstruction with a latissimus dorsi musculo-cutaneous flap. She reported that cutaneous lesions first appeared on the breast four weeks after the implementation of the radiotherapy, in June 1997, and then slowly spread around the surgical scar on the back but without any involvement of the flap itself. Clinical examination of the radiation field was otherwise normal, with no clinical lesion of chronic radiodermatitis. Two skin biopsies were performed and consistently showed in the upper dermis an infiltrate mainly composed of mononuclear cells stained with toluidine blue, leading to a diagnosis of mastocytosis of the urticaria pigmentosa subset. Slight epidermal aptrophy and dermal fibrosis were relevant to previous radiation. General examination failed to find any systemic symptoms such as flush, abdominal pain or diarrhea, dizziness or headache. Standard biological analyses were normal and blood and urine histamine levels were within normal range as well. The patient received no specific treatment but was warned about avoidance of histamine-releasing food and drugs.

Discussion

We present an unusual case of late-occurring urticaria pigmentosa quite peculiar by its localization since lesions were mainly distributed on an area of previous radiation. Only one similar observation is available, reporting on the occurrence of UP lesions strictly restricted to the irradiation field in a 61-year-old woman treated with surgery and radiotherapy (24 grays) for a breast carcinoma [1]. In this case, the lesions appeared four months after the implementation of radiotherapy which, as in our patient, supports an etiological role of radiation in the occurrence of urticaria pigmentosa lesions.
Localized UP is rarely reported in literature [2, 3]. External factors, like a Koebner’s phenomenon are likely to be involved in its pathomechanisms even if the pathways leading to the occurrence of mast cells infiltrate are not understood to date. In our case as in McDonald’s, radiation might represent a triggering factor resulting in Koebner’s reaction since it can indeed be pointed out that the lesions spared the skin of the flap, that was not previously irradiated; surgical scars (but not the flap itself), another possible triggering circumstance of Koebner’s reaction, were also involved in our patient. Additionally, Mc Donald and Feiwel reported on a non-published observation of UP occurring at the site of “a vigorous hypersensitivity reaction to Elastoplast” [1] which further substantiates the hypothesis of a Koebner’s reaction-induced UP whereas a case of UP appearing on a burned area was later published [4]. The role of ionizing radiation was hypothesized as well in a last patient who developped systemic mastocytosis after long term treatment with radioactive phosphorus for polycythemia vera [5].
The relationship between radiation therapy and mast cells infiltrate is still unclear but is perhaps reminiscent of the likely involvement of mast cells in the pathogenesis of fibrotic disorders like skin fibrosis, which is a well-known cutaneous side effect of radiation therapy [6]. However, in our case as in Mc Donald’s, mast cells were not randomly scattered but mainly gathered around dermal vessels, featuring typical lesions of UP. A role of the underlying neoplasia cannot be completely ruled out either since cutaneous mastocytoses are sometimes associated with internal malignancies, most often myeloid malignant hemopathies [7] perhaps through mast cells activation and/or enhanced adhesion induced by cytokines or adhesion molecules produced by the tumour cells. However, such a relationship is unlikely in our case as cutaneous lesions first appeared when the treatment was nearly completed and the patient was in complete remission. Furthermore, the association of mastocytosis with solid tumours seems insignificant unlike hemopathies.n

References

1. Mac Donald A, Feiwel M. Cutaneous mastocytosis: an unusual radiation dermatitis. Proc Roy Soc Med 1971; 64: 29-30.

2. Rosenberg FR, Berke M. Localisated urticaria pigmentosa. Arch Dermatol 1974; 109: 108.

3. Prens EP, Stolz E, Tank B, Vuzevski VD, Van Joost T. A rare clinical manifestation of localized cutaneous mastocytosis, J Am Acad Dermatol 1986; 15: 291-3.

4. Rampen F, Westerhof W. The isomorphic (Koebner) phenomenon in cutaneous mastocytosis. Acta Dermatol Venereol 1981; 61: 567-9.

5. Eagan JW, Baughman KL, Miller S, Conley CL, Eggleston JC. Systemic mastocytosis in a patient with polycythemia vera treated with radioactive phosphorus. Blood 1977; 49: 563-71.

6. Puxeddu I, Levi-Schaffer F. Mast cells and tissue remodelling. Rev Fr Allergol Immunol Clin 2002; 42: 16-8.

7. Travis WD, Bergstralh EJ. Solid and haematological malignancies in 60 patients with systemic mast cell disease. Arch Pathol Lab Med 1989; 113: 365-8.