Our patient was a 58-year-old Caucasian woman who had been diagnosed in September 1999 with estrogen receptor-positive (ER+), progesterone receptor-positive (PR+), human epidermal growth factor receptor 2/neu (Her2/neu)-negative ductal breast cancer assessed as American Joint Committee on Cancer stage IIA (pT1 pN1 M0 G1). She was initially treated with partial mastectomy and evacuation of axilla. No signs of disseminated disease were detected. Radiotherapy (50 Gy) was given to the left breast and lymph nodes. The patient received adjuvant tamoxifen therapy (20 mg/day) for five years, until January 2005. In 2003, she was diagnosed with hypothyroidism and treated with thyroxin substitution daily. In 2004, she was diagnosed with high blood pressure and was treated with metoprolol (47.5 mg/day). In March 2007, routine mammography showed a new local tumor in the left breast, and radical mastectomy was performed. The ductal residual tumor was assessed as pT1 pNX G2 and was ER+, PR+ and Her2/neu-negative. A palpable tumor was found at the left side of her neck, and a fine-needle biopsy showed metastasis of her breast cancer. A whole-body computed tomographic scan showed multiple liver metastases and multiple metastases in the left lung and the spleen. First-line chemotherapy was started with weekly paclitaxel 80 mg/m2 on days 1, 8 and 15 of a 28-day cycle and concomitant bevacizumab 10 mg/kg every two weeks. Her blood pressure was elevated after the first infusion, and the previous metoprolol dose was doubled to 90 mg/day. Her serum creatinine and bilirubin levels were normal (creatinine 77 μmol/L, normal range 50 to 90 μmol/L; bilirubin 18 μmol/L, normal range 5 to 25 μmol/L) before beginning therapy. Her serum alkaline phosphatase level was increased (214 U/L, normal range 35 to 105 U/L). After two combined infusions of paclitaxel-bevacizumab, an itchy papulosquamous rash was apparent on sun-exposed areas of the skin of her arms, legs and face. The rash was treated with cetirizine (10 mg/day) and topical corticosteroids. Her blood pressure was further elevated, and metoprolol was replaced by candesartan cilexetil-hydrochlorothiazide combination therapy. Her paclitaxel-bevacizumab treatment continued, but the rash on her arms and legs worsened. The patient was referred to a dermatologist, and skin biopsies were performed. The skin biopsy specimen showed non-specific inter-phase dermatitis, which may be associated with LE. A direct immunofluorescence study did not show deposition of immunoglobulins at the basement membrane zone, but C3 on Civatte bodies was positive. Simultaneously, her serum anti-SSA/Ro (> 240 U/mL, normal range 0 to 6.99 U/mL), anti-SSB/Ro (94.4 U/mL, normal range 0 to 6.99 U/mL) and anti-extractable nuclear antigen (anti-ENA) antibodies were positive. Paclitaxel-bevacizumab combination therapy was discontinued and replaced by cyclophosphamide, epirubicin, fluorouracil (CEF), after which her skin rash disappeared within two weeks. Her serum anti-SSA/Ro antibodies were 8.1 U/mL and her anti-SSB/Ro antibodies were 5.0 U/mL when checked three months after discontinuation of the therapy. Her serum anti-ENA antibodies were not checked. Her serum alkaline phosphatase level had decreased during therapy (from 274 U/L at maximum to 121 U/L, normal range 35 to 105 U/L), and her other liver enzyme values were not markedly changed.