CT guidance assisted by electromagnetic navigation system for percutaneous fixation by internal cemented screws (FICS).

PURPOSE: To evaluate electromagnetic navigation system (ENS) for percutaneous fixation by internal cemented screw (FICS) under CT guidance. BACKGROUND: FICS is a recently developed modality that consists in inserting screws, under imaging guidance, into bone through a minimal skin incision. FICS recently showed good efficacy for the palliation or prevention of pathologic fractures of the pelvic ring and femoral neck. MATERIALS AND METHODS: In this single-center retrospective study, we reviewed all consecutive cancer patients treated with percutaneous FICS under ENS-assisted CT guidance for the prevention or palliation of pelvic or femoral neck fractures. The primary endpoint was technical success. Secondary endpoints were screw placement accuracy (defined by proximal deviation p, distal deviation d, and angle deviation θ), radiation dose exposure, number of CT acquisitions, duration of procedures, and complications. RESULTS: Mean duration of FICS procedures was 111 ± 51 min. Mean post-procedure hospitalization length was 2.1 days. Technical success was achieved in 48 cases (96%) with a total of 76 screws inserted. Mean distance p, mean distance d, and mean angle θ were respectively 8.0 ± 4.5 mm, 7.5 ± 4.4 mm, and 5.4 ± 2°. Angle θ accuracy was higher for screws with a craniocaudal angulation of less than 20° (4.4° vs 6.4°, p = 0.02). The mean number of CT acquisitions during procedures was 6.4 ± 3.0. The mean dose length product was 1524 ± 953 mGy cm and the mean dose area product was 12 ± 8 Gy cm2. Five complications occurred in 4 patients. CONCLUSION: CT guidance assisted by ENS is an effective approach for percutaneous FICS. KEY POINTS: • ENS-assisted CT enables screw insertion in the pelvic ring and femoral neck, with a wide range of trajectories, even when a significant craniocaudal angulation is required. • ENS-assisted CT can be used as an alternative to CBCT guidance for percutaneous fixation by internal cemented screw. • ENS-assisted CT provides high technical success rate with excellent placement accuracy.

Does Bead Size Affect Patient Outcome in Irinotecan-Loaded Beads Chemoembolization Plus Systemic Chemotherapy Regimens for Liver-Dominant Colorectal Cancer? Results of an Observational Study.

PURPOSE: We investigated the clinical effects of bead size in irinotecan-loaded beads chemoembolization (DEBIRI) used for treating liver-dominant colorectal cancer. MATERIALS AND METHODS: Between March 2009 and January 2018, all consecutive patients with colorectal cancer liver metastases referred for DEBIRI at our tertiary center were included in an observational study. Patients were treated exclusively with either 100-mg irinotecan-loaded DC beads of 70-150 µm (small bead group or SB) or 100-300 µm (large bead group or LB) in diameter, in addition to systemic therapy. Liver tumor response rate at 3 months, liver and overall progression-free survival (PFS) and overall survival were estimated. RESULTS: In total, 84 patients with liver-dominant progressive disease underwent 232 DEBIRI sessions. Fifty-four patients were treated in the SB group and 30 patients in the LB group. Liver progression-free rates at 3 months were 86.7% for the LB group and 79.6% for the SB group (NS). Median liver-PFS and overall PFS were, respectively, 7.15 months and 7.15 months for the LB group and 7.65 and 7.55 months for the SB group (NS). Median overall survival was 13.04 months for the LB group and 15.59 months for the SB group (p = 0.04). Specific treatment grade 3 + 4 toxicity occurrence was 5 (17%) in the LB group and 20 (37%) in the SB group. CONCLUSION: No significant difference in patient outcome was observed between DEBIRI bead sizes of 70-150 µm and 100-300 µm. A trend toward higher treatment-specific toxicity was observed with the smaller beads.