# Anatomical Variation of the Thoracodorsal Nerve in Extensive Axillary Disease: A Case Report

## TL;DR

This case report describes a rare anatomical variation of the thoracodorsal nerve during axillary surgery for breast cancer.

## Contribution

The paper presents a rare anatomical variant of the thoracodorsal nerve and its clinical implications for axillary surgery.

## Key findings

- The thoracodorsal nerve was found posterior to the vascular pedicle, not in its expected position.
- The nerve was separated from the vascular pedicle by a large nodal mass before entering the latissimus dorsi muscle.
- The case highlights the importance of recognizing TDN variants to avoid injury during axillary surgery.

## Abstract

The thoracodorsal nerve (TDN) is an important anatomical landmark to identify and preserve during axillary surgery. We report a rare case of aberrant TDN anatomy in a 55-year-old female undergoing axillary lymph node dissection (ALND) for locally advanced left breast cancer. Intraoperatively, the TDN was not in its expected position in the axilla and, once identified, was observed passing posterior to the thoracodorsal vascular pedicle. The nerve was separated posteriorly from the vascular pedicle by a large nodal mass and remained posterior until entering latissimus dorsi (LD). This report discusses the current understanding of TDN variants and implications for misidentifying or injuring the TDN during axillary surgery. Understanding these variants is especially important in the climate of de-escalation of surgical management of the axilla in breast cancer.