Interventional oncology update

Abstract

Interventional Oncology (IO) is a subspecialty field of Interventional Radiology bridging between diagnostic radiology and the clinical oncology team, addressing the diagnosis and treatment of cancer. There have been many exciting advancements in the field of IO in recent years; far too many to cover in a single paper. To give each topic sufficient attention, we have limited the scope of this review article to four topics which we feel have the potential to drastically change how cancer is treated managed in the immediate future.

Keywords: Artificial intelligence; Breast ablation; Immune checkpoint inhibitors; Interventional oncology; Prostate ablation.

Fig. 1

Thermal ablation systems have both local and systemic effects on tumors. A. Heat-based modalities (e.g. radiofrequency ablation and microwave ablation) damage tumor cells in a number of ways and lead to the release of tumor antigens. B. The antigens released by dead tumor cells are taken up by antigen-presenting cells, such as dendritic cells. These present the antigens to T-cells, and can activate them through costimulatory checkpoint proteins (green). However, coinhibitory checkpoint proteins (red) on T-cells or tumor cells can cause T-cell apoptosis. C. Immune checkpoint inhibitors are antibodies which bind and inactivate coinhibitory proteins on T-cells and tumor cells, allowing activated T-cells to attack distant tumor cells.

Fig. 2

Abscopal effect in 77 year-old-man with metastatic renal cell carcinoma. A. 18FDG PET/CT MIP shows FDG-avid biopsy-proven right upper a right upper lobe pulmonary metastasis (black arrowhead) and right retroperitoneal recurrence (white arrowhead). B, C, D, and E. CT images show the pulmonary metastasis (black arrow) at the time of right retroperitoneal ablation (white arrows), and 1.5 years later which underwent gradual regression (dashed black arrow) in the absence of systemic treatment.

Fig. 3

MR-guided focal laser ablation of prostate cancer in a 59-year-old man with biopsy-proven Gleason 3 + 4 disease. On pre-procedure MRI, cancer in the right midgland transitional zone (red arrows) appears hyperintense on axial high b value DWI (A), hypointense on ADC (B), and hypointense with “erased charcoal” sign on the T2-weighted sequence (C). Note the BPH changes in the left midgland transitional zone (blue arrows). Intraprocedural T1-weighted axial images with Dotarem demonstrate non-enhancing ablation defects in the right midgland (green arrows) after treatment of the cancer (D) and subsequently a second ablation defect in the left midgland (yellow arrows) after treatment of BPH (E). Surveillance MRI 1.5 years later demonstrates marked shrinkage of the transitional zone (white arrows) with no residual or recurrent signal abnormality on high b value DWI (F), ADC (G), or T2-weighted images. At this time, the patient’s serum PSA had decreased from 6.1 preprocedurally to 1.3, and he reported a dramatic reduction in symptoms related to BPH with no change in erectile function.