A First Sign Not to be Missed: Cutaneous Metastasis from Breast Cancer

Cutaneous metastasis has a frequency of 1 to 10% among all metastatic cancer forms and breast cancer accounts for 30% of all cases. We report the case of a 73-year-old woman who presented with 4 skin lesions distributed across the upper trunk and abdomen; these had developed over a period of 12 months. Over the previous 6 months she had also developed anorexia, asthenia and weight loss. Upon investigation, a nodular mass was found in the left breast. Skin and breast mass biopsy were performed. Histology confirmed the diagnosis: infiltrating lobular breast cancer with cutaneous metastasis. The patient underwent hormonal treatment, mastectomy and radiotherapy. In rare cases, cutaneous metastasis appears as the first clinical manifestation of breast cancer. It is therefore crucial for patients and health professionals alike to be aware of new skin lesions. Cutaneous metastasis is a diagnostic sign of cancer that, it must be emphasised, is not restricted exclusively to later forms of the disease. LEARNING POINTS: Although breast cancer has the highest cutaneous metastasis rate among internal malignancies, cutaneous metastases actually occur in only a small minority of breast cancer patients. In rare cases, skin metastasis may appear as the first clinical manifestation of breast cancer. The clinical presentation of cutaneous metastasis from breast cancer can be varied, and therefore warrants greater awareness in clinical practice. Cutaneous metastasis from breast cancer typically carries a less unfavourable prognosis than cutaneous metastasis from other internal malignancies.