SummaryBasal cell carcinoma is the most common malignant skin tumour, but rarely appears in more than one location. For these multiple basal cell carcinoma (MBCC), lymphoedema seems to be a predisposing factor. We report the case of a patient with secondary lymphoedema, presenting with a 3-year-history of ulcerations and papules on her lymphoedematous leg. Histology confirmed the clinical diagnosis of MBCC in all lesions.Pathophysiologically, a strong risk factor for the development of MBCC in lymphoedema seems to be the local failure of immunosurveillance. In obstructive lymphoedema, an impairment of lymphocyte and Langerhans cell trafficking was observed, resulting in ineffective phagocytosis of foreign antigens. Consequently, lymphoedema is an immunologically vulnerable area, facilitating the development of MBCC. Nevertheless, other risk factors such as actinic skin damage and somatic mutations might also play a role in the development of MBCC in lymphoedema. Despite its rare occurrence, MBCC has to be taken into consideration in all suspicious skin lesions. Whenever in doubt, skin biopsy should be performed.