Serum KL-6 for diagnosis of ovarian carcinoma associated with dermatomyositis: two case reports and characteristic clinicopathological factors

Abstract

Patients with dermatomyositis have a predisposition to the development of malignant tumors. The incidence of ovarian carcinoma, especially, is higher in patients with dermatomyositis than in the general population. Recently, it was reported that serum levels of KL-6 (Krebs von den Lungen-6) may be elevated in patients with dermatomyositis associated with ovarian carcinoma. Herein, we describe two cases of ovarian carcinoma associated with dermatomyositis. The first patient was a 46-year-old woman with stage Ib serous papillary adenocarcinoma of the ovary. At the time of diagnosis, she had a 13-year history of dermatomyositis, and an elevated serum KL-6 level. Reduction of the serum KL-6 level was noted after resection of the tumor. Immunohistochemistry revealed positive staining of the tumor for KL-6. The other case was a 58-year-old woman with stage IV ovarian carcinoma who also had a history of dermatomyositis. She was initially started on chemotherapy, which resulted in shrinkage of the tumor and reduction of the serum KL-6 level. Surgery was then performed for resection of the tumor, and the chemotherapy was continued. However, the patient died of cancer 1 year and 4 months after the start of the treatment. For patients with dermatomyositis and with elevation of the serum KL-6 level in the absence of severe interstitial pneumonia, associated ovarian malignancy should be ruled out.