The status of axillary lymh node is the most important prognostic factor for staging of invasive breast cancer (1). Axillary lymph node dissection is the most important staging method in patients with clinically positive lymph node metastases or with histologically proven sentinel lymph node metastases. It is very important that axillary dissection should be performed adequately and without complications. To avoid complications during axillary dissection, anatomical structures should be exposed completely and anatomical variations must be recognized. Axillary arch or axillopectoral muscle is the most important anatomical variation (2). The rate of exposing the axillary arch during axillary dissection is % 0,25. However, anatomy textbooks report this rate as %7 (3). By this case, our aim was to present breast cancer cases with axillary arch, and to attract attention to the importance of performing axillary dissection adequately in those patients.
Keywords: axillary dissection, anatomic variation, axillary arch