Adam Robin Mohamed Macki Mohamed Fakih Jaafar Elmenini Sharath Kumar Anand Ian Lee
Henry Ford Health System
While the abscopal effect has been previously described, the phenomenon has been poorly defined with spinal metastases. This article is unique in that we present the first systematic review of the abs..
While the abscopal effect has been previously described, the phenomenon has been poorly defined with spinal metastases. This article is unique in that we present the first systematic review of the abscopal effect after radiation therapy to metastatic spinal cancer, especially since the spinal column represents one of the most common metastatic locations. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines in the Enhancing the QUAlity and Transparency Of health Research (EQUATOR) resources, a systematic review identified relevant studies via a computer-aided search of MEDLINE and Embase. Ten publications that met the inclusion and exclusion criteria from the PRISMA flow diagram described a total of thirteen patients. Important findings in this review of spinal metastases include (1) abscopal effect is more commonly observed when systemic therapy includes immunomodulators; (2) abscopal effect has a higher likelihood of success when immunomodulators are administered in conjunction with or after radiation therapy to the spine; (3) higher doses of radiation in a smaller number of fractions likely increase the abscopal success; and (4) ionizing radiation to the bone marrow of the spinal column may increase circulating lymphocytes that attack cancerous lesions elsewhere in the body. These trends, however, still require further investigation with experimental and clinical studies.