Complete Response to First-Line Trastuzumab Deruxtecan in Human Epidermal Growth Factor Receptor 2 (HER2)-Positive Extra-axial Central Nervous System Metastases.
- 1Medical Oncology, Unidade Local de Saúde (ULS) São João, Porto, PRT.
- 2Surgery, Unidade Local de Saúde (ULS) São João, Porto, PRT.
Abstract
Trastuzumab deruxtecan (T-DXd) is an antibody-drug conjugate approved for the treatment of unresectable or metastatic human epidermal growth factor receptor 2 (HER2)-positive breast cancer in patients who have received a prior anti-HER2-based regimen. HER2-positive breast cancer has a high propensity for central nervous system (CNS) spread, which confers significant morbidity and a poor prognosis. We report the case of a 47-year-old woman with metastatic HER2-positive breast cancer who developed debilitating symptomatic CNS metastases, predominantly extra-axial leptomeningeal lesions. Locoregional treatment options were not feasible, and the patient received off-label first-line systemic therapy with T-DXd. Rapid and marked neurological improvement was observed within weeks. Follow-up MRI at three months demonstrated complete radiologic resolution of all CNS lesions. As of April 2026, after 29 cycles of T-DXd, the patient remains clinically asymptomatic with no evidence of CNS disease on MRI, corresponding to a progression-free survival exceeding 20 months. This case highlights the potential role of T-DXd in symptomatic CNS metastases, particularly leptomeningeal disease, and underscores the need for prospective research into its intracranial efficacy in this distinct and challenging subset of patients.
Related
- Dramatic response to trastuzumab-deruxtecan in metastatic HER2-overexpressing vulvar extramammary Paget's disease: A case report
- From Lethargy to Recovery: Central Diabetes Insipidus from Pituitary Metastasis in Recurrent HER2-Positive Breast Cancer Treated with Fam-Trastuzumab Deruxtecan-Nxki
- Case Report: Trastuzumab-deruxtecan as 11th line therapy in a metastasized ovarian clear cell carcinoma patient expressing HER2 1+
- Progression-free survival of 23 months with second-line trastuzumab deruxtecan in HER2-positive gastroesophageal junction adenocarcinoma: a case report
- Adjuvant Trastuzumab Deruxtecan Versus Trastuzumab Emtansine by Residual Cancer Burden in HER2-Positive Early Breast Cancer: A Decision Analysis
BibTeX
@article{oura2026complete,
title = {{Complete Response to First-Line Trastuzumab Deruxtecan in Human Epidermal Growth Factor Receptor 2 (HER2)-Positive Extra-axial Central Nervous System Metastases.}},
author = {Maria João Oura and Rita Pinho and Fernando Osório and Miguel Barbosa and Ana Valente},
journal = {Cureus},
year = {2026},
month = sep,
doi = {10.7759/cureus.116819},
url = {https://europepmc.org/article/MED/42927259},
note = {CC BY},
}
RIS
TY - JOUR
TI - Complete Response to First-Line Trastuzumab Deruxtecan in Human Epidermal Growth Factor Receptor 2 (HER2)-Positive Extra-axial Central Nervous System Metastases.
AU - Maria João Oura
AU - Rita Pinho
AU - Fernando Osório
AU - Miguel Barbosa
AU - Ana Valente
PY - 2026
DA - 2026/09/24
JO - Cureus
DO - 10.7759/cureus.116819
UR - https://europepmc.org/article/MED/42927259
AB - Trastuzumab deruxtecan (T-DXd) is an antibody-drug conjugate approved for the treatment of unresectable or metastatic human epidermal growth factor receptor 2 (HER2)-positive breast cancer in patients who have received a prior anti-HER2-based regimen. HER2-positive breast cancer has a high propensity for central nervous system (CNS) spread, which confers significant morbidity and a poor prognosis. We report the case of a 47-year-old woman with metastatic HER2-positive breast cancer who developed debilitating symptomatic CNS metastases, predominantly extra-axial leptomeningeal lesions. Locoregional treatment options were not feasible, and the patient received off-label first-line systemic therapy with T-DXd. Rapid and marked neurological improvement was observed within weeks. Follow-up MRI at three months demonstrated complete radiologic resolution of all CNS lesions. As of April 2026, after 29 cycles of T-DXd, the patient remains clinically asymptomatic with no evidence of CNS disease on MRI, corresponding to a progression-free survival exceeding 20 months. This case highlights the potential role of T-DXd in symptomatic CNS metastases, particularly leptomeningeal disease, and underscores the need for prospective research into its intracranial efficacy in this distinct and challenging subset of patients.
SN - 2168-8184
ER -