Editor The current treatment strategies for patients with mycosis fungoides and Sézary syndrome had been published in the EORTC consensus recommendations for the treatment of mycosis fungoides/Sézary syndrome.1 In the early stages of cutaneous T-cell lymphoma (CTCL; mycosis fungoides, stages IA, IB and IIA), skin-directed therapies like topical corticosteroids, BCNU (carmustine), nitrogen mustard, bexarotene gel or systemic psoralen plus ultraviolet A (PUVA) phototherapy, UVB broad- or narrow-band phototherapy, localized radiotherapy or total skin electron beam therapy are recommended for first-line treatment. Here, we report a case of early-stage annular mycosis fungoides. A 38-year-old woman had been diagnosed with annular mycosis fungoides at the age of 19. Previous therapy included X-ray radiation (Dermopan) of the left flank and intermittent local corticosteroids. For 17 months, she received low-dose interferon alpha-2a, 6 million IU subcutaneously three times per week in combination with PUVA therapy, resulting in a complete response for 1 year. A flare-up was noticed around the irradiated skin area on the left flank. A 15 × 20 cm polycyclic annular erythematous plaque with fine scaling was seen (Fig. 1). The local treatment with corticosteroids had no benefit and the lesion grew larger centrifugally. A skin re-biopsy of the erythematous annular plaque was done. The biopsy showed a dense infiltrate of atypical lymphocytes, some forming groups within the epidermis (Pautrier micoabscesses) with a CD3+, CD4+ phenotype. The TCR-γ-PCR GeneScan analysis of the tissue showed a monoclonal T-cell population. The diagnosis of mycosis fungoides was confirmed. A 15 × 20 cm polycyclic annular erythematous plaque with fine scaling surrounding an area of post-irradiation hypo- and hyperpigmentation on the left flank. We discussed the therapeutic options such as localized PUVA therapy and systemic treatment with bexarotene with the patient. Radiotherapy was not recommended due to previous irradiation therapy leading to scaring. The patient preferred a wait-and-see strategy and refused the offered treatment options. At the same time, she started probiotic supplementation with Lactobacillus gasseri (8 × 108 to 8 × 109 KBE/g) and Bifidobacterium longum (8 × 108 to 8 × 109 KBE/g) daily for the prevention of intestinal infection. Probiotic supplements are generally well tolerated because the contained microorganisms are identical to those found in the human gastrointestinal tract. Interestingly, after 8 weeks of treatment with probiotic supplementation, the annular plaques changed colour to reddish-brown, and after 6 months, the lesions were almost gone (Fig. 2). The patient reported that she was not using any other ointment or therapy to treat the mycosis fungoides skin lesion. It could be speculated whether the complete regression of the annular mycosis fungoides skin lesion was induced by probiotic supplementation. However, clinical regression of annular mycosis fungoides lesions without therapy2 and a complete regression of CTCL, unspecified after skin biopsy, were described.3 Complete clearance of the mycosis fungoides lesion on the left flank after 6 months treatment with probiotic supplementation; only the irradiated skin was seen. Recent clinical trials have evaluated the clinical effectiveness of probiotics in the treatment and prevention of a wide range of acute and chronic gastrointestinal diseases,4,5 such as infectious diarrhoea, antibiotic associated diarrhoea, irritable bowel syndrome, inflammatory bowel disease and Helicobacter pylori infection. Several studies have also evaluated their efficacy in reducing the incidence of atopic clinical symptoms with promising results6 and other non-gastrointestinal diseases, such as respiratory infections, urogenital tract infections vaginitis and hypercholesterolaemia.5 There are various randomized studies and reports in the literature for the recommendation of probiotic supplementation in cancer prevention, particularly in colon,7 bladder, breast8 and liver cancer. Nevertheless, the clinical evidence for probiotic use in cancer prevention is insufficient. However, no successful treatment of cancer was reported. A recent study investigated the molecular mechanisms of pro-apoptotic effects of the probiotic Lactobacillus reuteri.9 They showed that L. reuteri promotes tumour necrosis factor–induced apoptosis in human myeloid leukaemia-derived cells by modulation of nuclear factor-kappa B (NK-kappaB) and mitogen-activated protein kinase signalling. This could be a possible explanation for the observed clinical effect because CTCL tumour cells are resistant to apoptosis by various mechanisms including constitutive activation of NF-kappaB.10 This might be the target of the probiotic bacteria in the tumour cells of our patient. However, it remains an open question if probiotics are able to induce apoptosis in CTCL tumour cells, and if sufficient dosages might reach the CTCL tumour cells in the skin. In conclusion, we present a patient with mycosis fungoides in whom probiotic supplementation may have lead to clearance of mycosis fungoides skin lesions.