Triple-target radiosurgery for intractable cancer pain of mixed origin: Two-centre experience in Central America

Cancer pain is one of the most severe components of the symptom burden among cancer patients, especially those with advanced or metastatic disease. Palliative interventions are necessary to alleviate cancer pain and reduce opioid-related side effects, thereby minimizing patient suffering. Radiosurgery has been effectively used to target the medial thalamus and the hypophysis for the treatment of chronic pain syndromes. These two areas are critical for pain modulation and control, and their precise targeting with radiosurgery and its non-invasive nature can provide relief for patients suffering from cancer-related intractable pain. Our previous work with single target irradiation of the hypophysis revealed promising pain relief in terminal cancer patients, albeit more suited for hormone-mediated tumours or bone-derived pain rather than complex mixed pain syndromes. Given that, we previously introduced the concept of triple-target irradiation (hypophysis + both thalami) in a small report of terminally ill cancer patients. Here, we report a larger case series of terminally ill patients (n = 8) with complex cancer pain treated with a triple-target approach, with radiation doses generally considered low or non-ablative (90 Gy), in contrast to the usual single-target, ablative approach comprising higher doses. We noted a substantial decrease in VAS scores and the medications needed to manage pain across all patients, experiencing minimal to no side effects. Our findings indicate that a minimally invasive triple-target method, utilising low radiation doses, effectively alleviates pain, lowers medication dependency, and enhances the quality of life with few side effects. Furthermore, additional research is essential to optimise pain relief and ensure long-term effectiveness.