Breast cancer in an intramammary sentinel node

Area of Science:

• Oncology
• Surgical Pathology

Background:

• Breast-conserving surgery is a common treatment for early-stage breast cancer.
• Sentinel lymph node biopsy (SLNB) is standard for staging axillary lymph nodes.
• Intramammary lymph nodes (IMLNs) are rarely considered in breast cancer staging.

Observation:

• A 3.2 cm infiltrating ductal carcinoma was surgically removed.
• Mammography and sonography revealed an unusual intramammary node.
• This node was located between the primary tumor and the axilla.

Findings:

• Isosulfan blue dye, used for sentinel node identification, also stained the intramammary node.
• Histopathological examination confirmed metastatic breast carcinoma foci within the stained intramammary node.
• The intramammary node contained carcinoma, suggesting it may act as a metastatic site.

Implications:

• The findings challenge the traditional exclusion of intramammary nodes in breast cancer staging.
• Excision of intramammary nodes may be warranted in select breast cancer patients undergoing breast conservation.
• Further research is needed to clarify the role of IMLNs in breast cancer metastasis and treatment strategies.