Paget's disease of the nipple with underlying occult invasive carcinoma detected by magnetic resonance imaging and second-look ultrasound: Case report.

INTRODUCTION: Paget's disease of the nipple (PDN) is a rare and often misdiagnosed condition characterized by the infiltration of adenocarcinoma cells into the nipple epidermis. It poses substantial diagnostic and therapeutic challenges due to its similarity to benign dermatological conditions and its association with in situ or invasive carcinoma.

CASE PRESENTATION: This report details the case of a 47-year-old woman with persistent nipple itching, rash, and occasional bloody discharge. No abnormalities were seen on the mammogram and ultrasound scans; punch biopsy was performed to confirm PDN. A small lesion missed by other imaging methods was detected via breast magnetic resonance imaging (MRI). A second-look ultrasound with needle localization enabled precise surgery. The pathology report after breast-conserving surgery (BCS) revealed invasive ductal carcinoma with no metastasis in the sentinel lymph node biopsy.

DISCUSSION: PDN often mimics benign skin conditions, leading to delayed diagnosis. Furthermore, timely identification is crucial as PDN is frequently associated with underlying breast malignancies. Additional imaging, such as breast MRI, is essential for comprehensive evaluation, as it can reveal hidden lesions previously undetected by conventional mammography and ultrasound. A second-look ultrasound guided needle placement for tumor localization, enhancing surgical precision, aesthetics, and reducing patient harm. Surgical management, including mastectomy, BCS with radiotherapy, and oncoplastic surgery, offers suitable options without affecting recurrence or survival in selected patients.

CONCLUSION: This case emphasizes the importance of employing additional imaging tools, such as breast MRI and second-look ultrasound for the early detection and surgical management of PDN.