Lymph nodes behind the axillary neurovascular bundle: case report and cadaveric study of frequency and distribution.

Axillary clearance was undertaken in a 58-year-old male with massive lymph node enlargement caused by melanoma from an unknown primary site. We discovered a group of metastatic lymph nodes behind the axillary neurovascular bundle. This group of nodes (retro-axillary lymph nodes) could represent an extension of the subscapular group, or the seventh group of axillary lymphoid nodes. They were successfully removed using an ad hoc surgical technique, and the subsequent findings are presented herein. To check the frequency of these lymph nodes in this area, we conducted a study on 15 cadavers (30 armpits). The technique of cadaveric sampling is described. Retro-axillary tissue was histologically processed to determine the number of lymph nodes present. It was found that lymph nodes were present in the defined area in 18 of the 30 (60 %) armpits explored. We recommend assessment of the retro-axillary space during surgery entailing massive axillary lymph node involvement.