57-year old female patient, after hair coloration, the swelling of the face and inflammation of the skin was noticed with apparent periorbital edema (Figure 1 | Figure 2 | Figure 3). Later, the patient noticed weakeness in the extremities. At physical examination, a lump was palpated in the left breast. Complex breast examination and US-guided biopsy from the lump was perfomed. Histology: invasive lobular cancer, ER: 80, PR: 50%, HER2: negative. Muscle biopsy: suspicion of myositis.

Diagnosis: advanced breast cancer, dermatomyositis syndrome as paraneoplastic syndrome

Multidisiplinary tumor board: high-dose Prednisolon therapy is recommended until the amelioration of the paraneoplastic syndrome, thereafter the performance of mastectomy and axillary blocdissection.

Histology at surgery: invasive ductal carcinoma, grade 3, pT1 (15 mm) pN1(2/2). Lymph vessel invasion, ER 80%. PR: 50%, HER2: negative

Postoperative radiotherapy (chest wall and lymph node regions), adjuvant chemotherapy with 6 cycles of CMF and supportive therapy with antiemetics, and following chemo, adjuvant endocrine treatment with aromatase inhibitor were delivered. The dose of Prednisolon could be continuously reduced and then its was omitted. The symptoms of dermatomyositis did not recur, and the patient is cancer-free.

Edited by László Halász