Clinically Positive Axillary Lymphadenopathy May Lead to False Diagnosis of Overstaged Breast Cancer in Patients with Sjögren's Syndrome: A Case Report.

Sjögren's syndrome (SS) is an autoimmune disease that chronic inflammation and lymph node proliferation. Patients with SS carry a greater risk of developing lymphoproliferative malignancy. In addition to other organ cancers, breast cancer may also occur in these patients. Considering these, breast cancer in patients with SS can be misdiagnosed as being in an advanced stage particularly in the presence of axillary lymphadenopathy. Here, we report a rare case of a 45-year-old woman with SS who presented with a breast mass. Radiology showed a 4 cm solid lesion and conglomerates of axillary lymphadonepathy. A breast biopsy revealed ductal carcinoma in situ. A modified radical mastectomy was performed; however, no axillary metastases were detected. Clinicians should remain vigilant to the possibility that a false clinical impression of axillary metastasis may occur in such patients with breast cancer. Therefore, axillary node status should be verified first.