Dermatomyositis as paraneoplastic syndrome of peritoneal and ovarian relapse after long-term complete remission in patient with metastatic bilateral breast cancer

Dermatomyositis is a rare disease characterised by inflammatory muscle affection and characteristic cutaneous changes. When occuring in a patient with cancer, dermatomyositis may indicate recurrence or progression and poor outcome. Herein, the treatment of metastatic breast cancer, metastatic pattern, characteristics of long-term survivors, and link between dermatomyositis and breast cancer are discussed and the literature reviewed. We report a 57-year old female patient with metastatic bilateral breast cancer whose ovarian and peritoneal relapse after long-term remission was disclosed by occurence of paraneoplastic dermatomyositis. The patient previously had a 15-year long disease free-period after primary treatment for breast cancer before onset of pulmonary dissemination. Following antracycline-based chemotherapy, the complete remission lasting another 15 years was accomplished. Dermatomyositis had been resolved upon induction of second-line taxane-based chemotherapy. After completion of six cycles of gemcitabine and paclitaxel chemotherapy, check-up revealed further progression. The patient subsequently underwent six cycles of third-line CAP chemotherapy (cyclofosfamide, doxorubicine, cisplatin) but disease progressed and oral capecitabine chemotherapy was initiated. The patient received four cycles of capecitabine followed by further vast progression and finally expired following massive pulmonary embolism. Our case stresses the need of thorough staging and check-up when dermatomyositis arises in patients with breast cancer, regardless of previous stable long-term complete remission. Furthermore, we believe that treatment with curative intent in young patients with metastatic breast cancer, who have good performance statuses and no comorbidities is required, because it is more likely to produce long-term complete remission. However, following disease relapse a poor outcome can be expected.