Mapping of postoperative lymphatic restructuring in breast reduction patients with indocyanine green lymphangiography

Breast cancer is the most commonly diagnosed type of cancer and is the leading cause of cancer-related deaths in women. Breast cancer typically metastasizes through lymphatic pathways. Breast reduction surgery is a procedure that aimed at reshaping the breast through resection of glandular tissues and excess skin, making it one of the most frequently performed surgeries in the field of plastic surgery. Considering that breast cancer is the most prevalent cancer in women and breast reduction surgery is a commonly performed procedure, changes in lymphatic pathways and metastatic routes may occur after breast reduction surgery. This situation could potentially alter the course of treatment in the event of possible breast cancer in individuals who have undergone breast reduction surgery. A total of 12 breast reduction patients with a family history of breast cancer, who underwent surgery at Akdeniz University Plastic Reconstructive and Aesthetic Surgery clinic between 01.01.2022 and 01.01.2024, were included in the study. Inferior pedicle technique was used in six patients, and superomedial pedicle technique was used in six patients. Preoperative, intraoperative, and postoperative ICG lymphangiography images were evaluated to map the lymphatic system. During surgery, care was taken to preserve the lymphatics included in the lateral and medial skin flaps by raising the flaps at an appropriate thickness. Lymphatics which included in the flaps were visualized using intraoperative ICG lymphangiography. Postoperative lymphatic mapping was conducted between 10th and 18th postoperative weeks. After detecting lymphatic vessels and flow patterns in ICG lymphangiography, the observed lymphatic vessels were traced on the patient's skin and analyzed. In postoperative ICG lymphangiography, lymphatics were mostly located in the upper outer quadrant, which were not present in preoperative images. It was thought that these postoperative lymphatics were formed through the mechanism of lymphangiogenesis, but a definitive conclusion regarding why these newly formed lymphatic structures were located in the upper outer quadrant could not be reached. In the postoperative ICG lymphangiography images of 4 patients operated with inferior pedicle technique and 3 patients operated with superomedial pedicle technique, lymphatic pathways oriented towards sternum were observed, which were not present in preoperative images. These newly observed lymphatic pathways oriented towards sternum which we believe to have formed through the lymphangiogenesis mechanism, may have created a previously non-existent connection between the superficial and deep lymphatic network and may have been restructured to drain into the internal mammary lymph nodes. This study is the first to evaluate postoperative lymphatic restructuring in breast reduction patients with ICG lymphangiography. We believe that the data obtained in our study will significantly contribute to the diagnosis, treatment, and follow-up processes of breast cancer patients with a history of breast reduction surgery. Key words: Breast reduction, lymphangiogenic, ICG lymphangiography, lymphatic system