Discordant pathologic response to neoadjuvant human epidermal growth factor receptor 2-directed therapy in primary breast tumour and axillary lymph node metastases.
Yanina Nikolaus
✦ AI-curated · Sources linked
Case in brief
A patient with HER2-positive breast cancer received neoadjuvant chemotherapy and HER2-directed therapy, showing significant histological response in the primary breast tumor. However, multiple axillary lymph nodes exhibited persistent viable metastatic carcinoma without any treatment effect. This case illustrates the discrepancy in treatment response between primary and metastatic sites.
What made this case unusual
The case highlights a marked histological response in the primary tumor contrasted by viable metastatic carcinoma in axillary lymph nodes, demonstrating biological heterogeneity.
Diagnostic / clinical pearl
Clinicians should be aware that a favorable response in the primary tumor does not guarantee similar outcomes in metastatic lymph nodes, necessitating independent evaluation.
Why it matters
Understanding discordant responses is crucial for accurate staging and treatment planning in patients with breast cancer, impacting prognosis and management strategies.