A Case of Breast Cancer Associated with SAPHO Syndorome and Ulcerative Colitis Mimicking Bone Metastasis

Abstract

SAPHO syndrome is a disease associated with synovitis, acne vulgaris, palmar pustulosis, hyperostosis, and osteitis. These bone lesions require differentiation from bone metastasis in imaging studies. The disease has been suggested to have some correlation with inflammatory diseases. We report a case of SAPHO syndrome in which we had difficulties in differentiating it from bone metastasis of breast cancer. The patient was a 57-year-old woman who had a history of ulcerative colitis. In May 2014, she had been operated on for right breast cancer, when the resected specimen was diagnosed as papillary ductal carcinoma with the infiltrating diameter of 6 mm, pT1N0M0 and pStage I. She had been observed under postoperative hormone therapy. Starting in December 2016, she developed low back pain, and PET-CT and MRI scans disclosed lesions at the L1-5 and S1. Multiple bone metastases were suspected. On the same time, eczema affected her hands and foot and palmar pustulosis was diagnosed. Since the possibility of postoperative early recurrence of breast cancer was low and arthritis associated with palmar pustulosis was identified, SAPHO syndrome was suspected. Accordingly, we continued the same treatment and carefully followed her clinical course. MRI conducted one year later showed an improvement tendency of the bone lesions and she has been free from recurrence and aggravation, as of August 2018.