The role of 3D-CT mammary lymphography with the arm lymph flow enhancement on sentinel node biopsy and selective axillary dissection.

Abstract

e11504 Background: In early breast cancer, the presence of metastasis in axillary lymph nodes (AN) is an important factor in prognosis and further treatment. However, AN dissection causes many complications such as contracture of shoulder joint, lymph edema, and paralysis of upper extremities. Sentinel node (SN) biopsy provides us a valuable information about no need to dissect AN for node-negative patients. However, on node-positive patients, the conventional AN dissection has been performed. 3D-CT lymphography (LG) can show the precise individual lymphatic flow not only from the breast tumor to SN but also from SN to venous angle, which means breast lymphatic channel. We applied 3D-CT LG to distinguish them from the arm channel to avoid any arm complications. Methods: 3D-CT LG was performed before surgery to mark SN on the skin. Above the tumor and near the areola and the arm pit, 2 ml of Iopamidol 300 was injected subcutaneously. Images of CT scan were taken at 1, 3 and 10 min after injection. They were reconstructed to produce a 3D image of lymph ducts and lymph nodes by the volume rendering software. The axillary node groups were classified to 5 groups as described before. The arm lymph channel was classified to 4 regions. SN biopsy and AN sampling were performed by dye-staining method using endoscopy. Results: We have performed 3D-CT LG on 200 patients and evaluated the arm lymph flow on 50 patients. The average age was 55.1 years old. The average tumor size was 2.4 cm. The average sampled number of SN was 2.3. The arm lymph channels were observed at 10 minutes after injection. They were divided into 4 directions: around and above the axillary vein (64%), the axilla (12%), the supraclavicule (8%), and the lateral chest (16%). The connection between the breast and the arm channel was observed in each five groups of axillary nodes shown by 3D-CT LG. We could detect their position on the axillary lymphatic mapping by 3D-CT LG during surgery. The selective axillary dissection can be performed by avoiding the arm lymph channel. Conclusions: The arm lymph channel can be observed by 3D-CT LG with the arm enhancement, which will help the selective axillary dissection to prevent the arm lymph edema.