While blinatumomab-TKI combinations avoid systemic chemotherapy toxicity, they are associated with higher rates of central nervous system (CNS) relapses. This necessitates an increased number of intrathecal chemotherapy doses to prevent CNS disease, a critical nuance for managing this 'simpler' approach.
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The treatment backbone for Ph+ ALL is shifting away from intensive chemotherapy like hyper-CVAD. Chemotherapy-free regimens combining blinatumomab with a TKI (preferably ponatinib) are becoming the new standard, showing outcomes that are at least as good as, and likely better than, traditional chemotherapy.
Real-world data suggests that using one antibody-drug conjugate (ADC) immediately after another is often ineffective. A potential strategy to overcome this resistance is to administer a different class of chemotherapy before starting the second ADC.
An expert argues the path to curing metastatic cancer may mirror pediatric ALL's history: combining all highly active drugs upfront. Instead of sequencing treatments after failure, the focus should be on powerful initial regimens that eradicate cancer, even if it means higher initial toxicity.
The B7H3-targeted antibody-drug conjugate (ADC) ifanatumab deruxtecan shows a high intracranial response rate in SCLC, numerically even better than its systemic response rate. This suggests excellent CNS penetration, offering a promising strategy for managing brain metastases, a common and difficult challenge in SCLC.
With new CNS-active drugs dramatically improving survival after a brain metastasis diagnosis, some experts are now advocating for routine screening brain MRIs in high-risk patients. The goal is to detect asymptomatic lesions early, potentially preventing catastrophic neurologic events like seizures.
Despite the high likelihood (75%) of a T315I mutation at relapse on first or second-generation TKIs, testing is not critical for the immediate treatment decision. The most potent TKI, ponatinib, would be the next line of therapy regardless of the mutation status, making the test more of a confirmation than a decision driver.
For patients with otherwise well-controlled disease who develop isolated oligoprogression in the brain, evidence suggests a better survival outcome from adding local therapy (like SRS) and continuing the current effective systemic therapy, rather than switching the systemic regimen entirely.
When treating testicular DLBCL, administering systemic methotrexate for CNS prophylaxis before testicular radiation is crucial. Reversing the order can cause a severe skin reaction known as radiation recall, a critical and potentially dangerous complication.
A key nuance in managing ponatinib for Ph+ ALL is a response-adapted dosing strategy. Patients are typically started at a 30mg dose, which is then reduced to 15mg once a good minimal residual disease (MRD) response is achieved. This approach aims to maintain efficacy while mitigating long-term toxicity.
The development of new KIT inhibitors like bezuclastinib is largely fueled by the need for alternatives to high-dose avapritinib in advanced SM. Concerns about cognitive effects and rare intracranial hemorrhage with avapritinib create an opportunity for agents with less blood-brain barrier penetration.
