Abscopal Effect on Bone Metastases from Solid Tumors: A Systematic Review and Retrospective Analysis of Challenge within a Challenge

Abstract

Background: Abscopal effect (AE) describes the ability of radiotherapy (RT) to induce immune-mediated responses in nonirradiated distant metastasis. Bone represents the third most frequent site of metastasis and an immunologically favorable environment for the proliferation of cancer cells. We revised the literature, searching documented cases of AE involving bone metastases (BMs) and evaluated the incidence of AE involving BMs in patients requiring palliative RT on BMs or non-BMs treated at our department. Methods: Articles published in the PubMed/MEDLINE database were selected using the following search criteria: ((abscopal effect)) AND ((metastases)). Patients with BMs, who underwent performed bone scintigraphy before and at least 2–3 months after RT, were selected and screened between January 2015 and July 2022. AE was defined as an objective response according to the scan bone index for at least one nonirradiated metastasis at a distance > 10 cm from the irradiated lesion. The primary endpoint was the rate of AE on BMs. Results: Ten cases experiencing AE of BMs were identified from the literature and eight among our patients. Conclusions: The analysis performed here suggests the use of hypofractionated radiotherapy as the only triggering factor for AE of BMs through the activation of the immune response.

Radio-Guided Lung Surgery: A Feasible Approach for a Cancer Precision Medicine

“…Moreover, enlarged lymph nodes are present in 40% of benign cases, while normal nodes can be involved in 25% of cases. Moreover, it is common that some nodal stations can be skipped, so the standard surgical operation practice involves conducting a complete lymphadenectomy that is not burdened with morbidity [ 14 , 15 , 16 , 17 , 18 , 19 ]. In addition, 40% of early lung cancer cases have micrometastasis at surgery time [ 20 ].…”