A Successfully Treated Case of Intrahepatic Cholangiocarcinoma with Exacerbation of Dermatomyositis

Dermatomyositis (DM) is often found in conjunction with malignant tumors such as lung, cervical, and breast cancer. However, the association with intrahepatic cholangiocarcinoma (ICC) is extremely rare. Moreover, to our knowledge, there have been no previous reports of DM discovered because of exacerbation of DM. Our case was a 44-year-old female with dry cough, myalgia, and arthralgia. We performed hepatic resection for intrahepatic ICC. She was diagnosed with DM, and combination treatment with prednisolone and tacrolimus was started. During outpatient visits, her symptoms worsened, and she was hospitalized due to deterioration of her primary disease. On detailed examination, a malignant lesion in the liver was discovered. After operation, the symptoms of DM remain stable by taking prednisolone and tacrolimus. The patient was suspected to have paraneoplastic syndrome, which was discovered due to the exacerbation of the DM that was caused by the intrahepatic ICC.