Local Therapy for Isolated Central Nervous System Progression Among Patients Receiving Antibody-Drug Conjugate...

Area of Science:

• Oncology
• Radiation Oncology
• Medical Oncology

Background:

• Antibody drug conjugates (ADCs) are vital in treating various cancers, including breast, lung, and urothelial malignancies.
• Guidelines advocate for local therapy combined with continued systemic treatment for isolated brain relapse.
• Clinical outcomes of this guideline-concordant approach in patients receiving ADCs are not well-documented.

Purpose of the Study:

• To evaluate the clinical outcomes of local therapy for isolated brain progression in patients undergoing ADC treatment.
• To assess overall survival, progression-free survival, and the need for subsequent therapies after local treatment for brain metastases.

Main Methods:

• A retrospective analysis of patients receiving ADCs who developed isolated brain progression and underwent radiation therapy (RT).
• Patients were categorized as oligoprogressive if they had ≤3 brain metastases at recurrence.
• Endpoints included overall survival, progression-free survival (PFS), and cumulative incidence of next therapy.

Main Results:

• Seventeen patients received concurrent ADC and RT (13 SRS, 4 WBRT) for isolated brain progression.
• Median overall survival was 19 months, and median PFS was 8.1 months, with a low cumulative incidence of local failure (1.6% at 24 months).
• The cumulative incidence of requiring next-line therapy was 71% at 12 months, significantly lower in oligoprogressive cases.

Conclusions:

• This study is the first to report outcomes of guideline-recommended local therapy for isolated brain relapse in patients on ADCs.
• Local therapy can effectively manage isolated brain progression, potentially delaying the need for subsequent systemic therapies.
• The findings support the continued use of local therapy, especially for patients with oligoprogressive disease, in conjunction with ADC treatment.