[Subacute cutaneous lupus erythematosus and cancer: two cases and literature review].

BACKGROUND: Subacute cutaneous lupus erythematosus is an uncommon dermatosis characterised by a non-scarring, annular photo-distributed dermatosis associated with anti-Ro/SSA antibodies. It is remarkable as a paraneoplastic syndrome (12 cases in the literature). We report two cases of subacute cutaneous lupus erythematosus occurring in patients treated for metastatic breast adenocarcinoma.

CASE REPORTS: Case 1: a 72-year-old woman with breast carcinoma relapsing after surgery, chemotherapy, hormone therapy, and without treatment for 6 months, was admitted for an acute erythematous slightly squamous and photo-distributed eruption. On clinical examination, she was found to be presenting polyadenopathy and pleural effusion. Case 2: a 46-year-old woman with a history of breast carcinoma was admitted for an erythematopapular, annular and photo-distributed eruption occurring after a second breast cancer relapse and five months after initiation of docetaxel. A new line of chemotherapy initially resulted in regression of the lesions, and progression of the breast cancer was associated with cutaneous relapse.

DISCUSSION: The diagnosis of subacute cutaneous lupus erythematosus was supported in our two patients by the presence of an annular photo-distributed eruption associated with positive testing for anti-Ro/SSA antibodies. Occurrence of the eruption in both cases with relapse of the neoplasia and its improvement after oncological treatment reinforced the diagnosis of paraneoplastic syndrome in one case, and the use of chemotherapy known to trigger lupus could have suggested a diagnosis of drug-induced subacute cutaneous lupus erythematosus. Thus, the association between lupus and cancer is relevant.