To evaluate the efficacy of HER2-targeted antibody-drug conjugates (ADCs) in patients with rare tumors exhibiting ERBB2 gene amplification, highlighting its significance in treatment decisions.
Key Findings:
All patients achieved meaningful objective responses despite heterogeneous histology and low-to-equivocal IHC scores, with specific treatment regimens noted.
Responses included a 301-day partial remission and a complete response in one case using sequential ADC therapy.
High-level gene amplification was predictive of ADC efficacy, independent of IHC status.
Interpretation:
The findings suggest that integrating NGS into diagnostic workflows can identify patients with rare tumors who may benefit from HER2-targeted therapies, challenging traditional reliance on IHC scores and emphasizing the need for clinical practice adaptation.
Limitations:
Small sample size limits generalizability.
Retrospective nature may introduce bias in treatment selection and outcome assessment.
Lack of long-term follow-up data.
Conclusion:
HER2-targeted therapies may provide clinical benefit in rare tumors with ERBB2 amplification, highlighting the need for refined testing strategies to identify potential responders and the role of NGS in this process.
