Role of palliative radiotherapy in brain metastases

Treatment and Prevention of Brain Metastases in Small Cell Lung Cancer

Central nervous system (CNS) metastasis will develop in 50% of small cell lung cancer (SCLC) patients throughout disease course. Development of CNS metastasis poses a particular treatment dilemma due to the accompanied cognitive changes, poor permeability of the blood-brain barrier to systemic therapy and relatively advanced state of disease. Survival of patients with untreated SCLC brain metastases is generally <3 months with whole brain radiotherapy used as first-line management in most SCLC patients. To prevent development of CNS metastasis prophylactic cranial irradiation (PCI) is recommended in limited stage disease, after response to chemotherapy and radiation, while PCI may be considered in extensive stage disease after favorable response to upfront treatment. Neurocognitive toxicity with whole brain radiotherapy and PCI is a concern and remains difficult to predict. The mechanism of toxicity is likely multifactorial, but a potential mechanism of injury to the hippocampus has led to hippocampal sparing radiation techniques. Treatment of established non-small cell lung cancer CNS metastases has increasingly focused on using stereotactic radiotherapy (SRS) and it is tempting to extrapolate these results to SCLC. In this review, we explore the evidence surrounding the prediction, prevention, detection, and treatment of CNS metastases in SCLC. We further review whether existing evidence supports extrapolating less toxic treatments to SCLC patients with CNS metastases and discuss trials that may shed more light on this question.

Stroke-Like Migraine Attacks After Radiation Therapy (SMART) Syndrome: A Comprehensive Review

PURPOSE OF REVIEW

SMART syndrome is a delayed complication of cranial irradiation that can be misconstrued as tumor recurrence or some other intracranial neurological disease. Recognition of this clinical syndrome is imperative as it can obviate the need for invasive diagnostic testing and can provide reassurance to both the patient and their loved ones.

RECENT FINDINGS

SMART syndrome is generally considered a reversible clinical syndrome; however, neurological deficits may become permanent. Pathophysiology of SMART syndrome may involve cerebrovascular autoregulation impairment, neuronal dysfunction leading to trigeminovascular system impairment and/or cortical spreading depression, and seizures. In addition to MRI brain with gadolinium, other imaging modalities, such as CT perfusion, MR perfusion, MR spectroscopy, and FDG PET/CT, aid in arriving to the diagnosis sooner. Patients should also undergo electroencephalogram in order to promptly identify and treat seizures. There are currently no clear guidelines on how to effectively treat SMART syndrome, but treatment may involve anti-seizure medication, anti-hypertensives, anti-platelet, and steroid therapy. This review provides a comprehensive understanding of the clinical characteristics of SMART syndrome from presentation to diagnostic evaluation. We also discuss radiographic features and treatment strategies for this rare disease. With increased radiotherapy utilization, prompt clinical recognition of SMART syndrome and further development of a comprehensive diagnostic approach to SMART syndrome utilizing newer radiographic modalities as well as treatment algorithms to effectively treat this clinical condition will be imperative.

Survival outcomes after whole brain radiotherapy for brain metastases in older adults with newly diagnosed metastatic small cell carcinoma: A national cancer database (NCDB) analysis

BACKGROUND

Small cell lung cancer (SCLC) is an aggressive malignancy with a tendency to affect older adults and also metastasize to the brain. Older adults tolerate whole brain radiotherapy (WBRT) poorly with marginal survival benefit. We utilized the national cancer database (NCDB) to evaluate the survival outcomes following WBRT in older adults with SCLC and brain metastases.

METHODS

We identified 1615 patients ≥75 years old diagnosed with SCLC and brain metastases. Patients were categorized by type of therapy: chemotherapy + WBRT (n = 576), chemotherapy alone (n = 238), WBRT alone (n = 360) and no chemotherapy or WBRT (n = 441). Clinical and demographic characteristics were reported for each treatment cohort with a subsequent multivariable regression analysis for survival.

RESULTS

Median patient age was 79 years. WBRT median dose was 30 Gy. At time of analysis, 1530 of the cohort had died, yielding a median OS of 2.9 months and 6 month survival of 31% for patients that received chemotherapy. For patients treated without chemotherapy, median OS with WBRT was 1.9 months compared to 1.2 months without (p < .0001). For patients receiving chemotherapy with, and without WBRT, median OS was 5.6 months and 6.4 months, respectively (p = .43). Multivariable cox regression revealed age > 80, extracranial disease, male sex, and rural location as predictors of increased risk of death.

CONCLUSION

In older adult patients with SCLC brain metastasis, WBRT was associated with a modest increase in survival in patients not fit for chemotherapy, and there was no association with increased survival over chemotherapy alone.

Radiation-Induced Neuropsychiatric Manifestations in a Patient with Brain Metastasis: A Diagnostic and Therapeutic Challenges for Consultation-Liaison Psychiatrist

The aim of this case report is to highlight diagnostic and therapeutic challenges for consultation-liaison psychiatrist in the case of radiation-induced neuropsychiatric syndrome. We report the case of a 61-year-old man presented with neurological and psychiatric manifestations following the radiation therapy for non-small cell lung carcinoma with brain metastasis. We have briefly reviewed and discussed the risk factors, clinical features, diagnostic, therapeutic, and preventive aspect of radiation-induced neuropsychiatric manifestations.

Mechanisms of radiotherapy-associated cognitive disability in patients with brain tumours

Standard treatment of primary and metastatic brain tumours includes high-dose megavoltage-range radiation to the cranial vault. About half of patients survive >6 months, and many attain long-term control or cure. However, 50-90% of survivors exhibit disabling cognitive dysfunction. The radiation-associated cognitive syndrome is poorly understood and has no effective prevention or long-term treatment. Attention has primarily focused on mechanisms of disability that appear at 6 months to 1 year after radiotherapy. However, recent studies show that CNS alterations and dysfunction develop much earlier following radiation exposure. This finding has prompted the hypothesis that subtle early forms of radiation-induced CNS damage could drive chronic pathophysiological processes that lead to permanent cognitive decline. This Review presents evidence of acute radiation-triggered CNS inflammation, injury to neuronal lineages, accessory cells and their progenitors, and loss of supporting structure integrity. Moreover, injury-related processes initiated soon after irradiation could synergistically alter the signalling microenvironment in progenitor cell niches in the brain and the hippocampus, which is a structure critical to memory and cognition. Progenitor cell niche degradation could cause progressive neuronal loss and cognitive disability. The concluding discussion addresses future directions and potential early treatments that might reverse degenerative processes before they can cause permanent cognitive disability.