Abscopal effect in maxillary sinus cancer: Insights from two case reports and a literature review.

ABSTRACT

BACKGROUND: The abscopal effect is a rare phenomenon in which localized radiation therapy triggers tumor reduction in nontargeted areas. Although this phenomenon has been observed in various cancer types, it remains infrequent and not fully understood. CASE Two patients with maxillary sinus cancer with distant metastases were treated with radiotherapy after immune checkpoint inhibitor (ICI) therapy. The patients demonstrated abscopal effects following ICI therapy and radiotherapy, showing shrinkage in metastatic areas not directly targeted by radiation. CONCLUSION: This report was reviewed to examine the synergistic effects of ICI and radiotherapy and to identify optimal strategies to enhance the abscopal effect in clinical practice. It has also touched on various ongoing debates and clinical trials aimed at understanding and exploiting this effect to improve cancer treatment. The exact mechanisms and optimal treatment protocols remain areas for future research.