Abstract
INTRODUCTION: Peutz-Jeghers syndrome (PJS) is a rare autosomal dominant disorder characterized by mucocutaneous pigmentation and gastrointestinal hamartomatous polyps. Women with PJS have a significantly increased risk of breast cancer, with surveillance recommended from an early age. CASE PRESENTATION: A 36-year-old premenopausal woman with PJS was found to have a suspicious lesion in the right breast during routine ultrasound. Subsequent MRI demonstrated an enhancing lesion extending close to the nipple, and biopsy revealed ductal carcinoma in situ. Mammography showed widespread microcalcifications. She underwent right total mastectomy with sentinel lymph node biopsy, followed by immediate reconstruction with tissue expander and later implant exchange with fat grafting. No adjuvant radiotherapy or systemic therapy was administered. She has remained disease-free for 2.5 years postoperatively. CONCLUSION: This case demonstrates that structured breast surveillance in PJS can facilitate early detection of breast cancer. It underscores the clinical value of regular surveillance in hereditary cancer syndromes and supports the inclusion of breast screening as part of the comprehensive management of PJS.