Is the Berg axillary lymph node categorization useful in the 3D environment?

Area of Science:

• Anatomy
• Radiology
• Oncology

Background:

• The Berg muscle-based categorization of axillary lymph node levels (LNL) is crucial for breast cancer staging.
• Its reliability across different arm positions and in 3D radiation planning is not well-established.

Purpose of the Study:

• To evaluate the reproducibility of Berg LNL categorization with varying arm positions.
• To assess the utility of this categorization in 3D radiation treatment planning.

Main Methods:

• CT scans of 16 patients were analyzed in two arm positions: historical (90° abduction) and standard (arms overhead).
• Comparison of LNL volumes, contents, and locations relative to anatomical landmarks and surgical structures.

Main Results:

• LNL volumes remained consistent, but LNL positions shifted significantly relative to the third thoracic vertebra (T3) with arm elevation.
• Pectoral muscles and axillary vessels also showed significant positional changes (medial and anterior displacement).
• Discrepancies in lymph node (LN) and clip coverage were noted in over 60% of cases for Level II.

Conclusions:

• Arm position significantly alters the perceived location of Berg LNLs and surrounding structures.
• This variability compromises the reliability of objective comparisons of data collected in different arm positions.
• Awareness of these positional changes is essential for surgeons, radiologists, and radiation oncologists in breast cancer management.