(4) Actinic reticuloid: is it pre‐malignant?

Actinic reticuloid (AR) is a severe idiopathic, chronic, predominantly eczematous photodermatosis of elderly patients, characterized by marked photosensitivity to both UVB (280‐315 nm) and UVA (315–400 nm) spectral wavebands. Cutaneous histopathological changes include a deep, dense lymphohistiocytic infiltrate sometimes containing mononuclear cells with hyperchromatic and convoluted nuclei, giant cells, Pautrier‐like micro‐abscesses and a resemblance to cutaneous T cell lymphoma. It has been suggested that progression to lymphoma can occasionally occur 1 , although this remains controversial. Aneuploidy, the occurrence of abnormal chromosomes, is present in 70–90% of solid malignant tumours and has been observed in pre‐malignant conditions such as chronic atrophic gastritis, congenital pigmented hairy naevi and Bowen's disease. 2 It has not, however, so far been identified in any entirely benign condition and its presence is thus considered implicit of malignancy or malignant potential. Flow cytometry (FCM) using DNA‐specific stains permits the analysis of cellular DNA content and thus identification of anomalous chromosomes (aneuploidy). We have performed FCM on biopsies from six male AR patients aged 59–79 years. Formalin‐fixed skin was processed with a FACS analyser. Dermal inflammatory cells and keratinocytes were assessed separately. No evidence of aneuploidy was noted in any patient. This suggests that AR is not a pre‐malignant condition.