The Confluence of Stereotactic Ablative Radiotherapy and Tumor Immunology

Stereotactic radiation approaches are gaining more popularity for the treatment of intracranial as well as extracranial tumors in organs such as the liver and lung. Technology, rather than biology, is driving the rapid adoption of stereotactic body radiation therapy (SBRT), also known as stereotactic ablative radiotherapy (SABR), in the clinic due to advances in precise positioning and targeting. Dramatic improvements in tumor control have been demonstrated; however, our knowledge of normal tissue biology response mechanisms to large fraction sizes is lacking. Herein, we will discuss how SABR can induce cellular expression of MHC I, adhesion molecules, costimulatory molecules, heat shock proteins, inflammatory mediators, immunomodulatory cytokines, and death receptors to enhance antitumor immune responses

The confluence of stereotactic ablative radiotherapy and tumor

Stereotactic radiation approaches are gaining more popularity for the treatment of intracranial as well as extracranial tumors in organs such as the liver and lung. Technology, rather than biology, is driving the rapid adoption of stereotactic body radiation therapy (SBRT), also known as stereotactic ablative radiotherapy (SABR), in the clinic due to advances in precise positioning and targeting. Dramatic improvements in tumor control have been demonstrated; however, our knowledge of normal tissue biology response mechanisms to large fraction sizes is lacking. Herein, we will discuss how SABR can induce cellular expression of MHC I, adhesion molecules, costimulatory molecules, heat shock proteins, inflammatory mediators, immunomodulatory cytokines, and death receptors to enhance antitumor immune responses

The confluence of stereotactic ablative radiotherapy and tumor immunology.

Stereotactic radiation approaches are gaining more popularity for the treatment of intracranial as well as extracranial tumors in organs such as the liver and lung. Technology, rather than biology, is driving the rapid adoption of stereotactic body radiation therapy (SBRT), also known as stereotactic ablative radiotherapy (SABR), in the clinic due to advances in precise positioning and targeting. Dramatic improvements in tumor control have been demonstrated; however, our knowledge of normal tissue biology response mechanisms to large fraction sizes is lacking. Herein, we will discuss how SABR can induce cellular expression of MHC I, adhesion molecules, costimulatory molecules, heat shock proteins, inflammatory mediators, immunomodulatory cytokines, and death receptors to enhance antitumor immune responses

Patient-reported quality of life after stereotactic body radiation therapy versus moderate hypofractionation for clinically localized prostate cancer

Evaluate changes in bowel, urinary and sexual patient-reported quality of life following treatment with moderately hypofractionated radiotherapy (<5Gray/fraction) or stereotactic body radiation therapy (SBRT;5–10Gray/fraction) for prostate cancer. In a pooled multi-institutional analysis of men treated with moderate hypofractionation or SBRT, we compared minimally detectable difference in bowel, urinary and sexual quality of life at 1 and 2years using chi-squared analysis and logistic regression. 378 men received moderate hypofractionation compared to 534 men who received SBRT. After 1year, patients receiving moderate hypofractionation were more likely to experience worsening in bowel symptoms (39.5%) compared to SBRT (32.5%; p=.06), with a larger difference at 2years (37.4% versus 25.3%, p=.002). Similarly, patients receiving moderate fractionation had worsening urinary symptom score compared to patients who underwent SBRT at 1 and 2years (34.7% versus 23.1%, p<.001; and 32.8% versus 14.0%, p<.001). There was no difference in sexual symptom score at 1 or 2years. After adjusting for age and cancer characteristics, patients receiving SBRT were less likely to experience worsening urinary symptom scores at 2years (odds ratio: 0.24[95%CI: 0.07–0.79]). Patients who received SBRT or moderate hypofractionation have similar patient-reported change in bowel and sexual symptoms, although there was worse change in urinary symptoms for patients receiving moderate hypofractionation