Outcomes Following Percutaneous Microwave and Cryoablation of Lung Metastases from Adenoid Cystic Carcinoma of the Head and Neck: A Bi-Institutional Retrospective Cohort Study

The aim of this study was to report outcomes following percutaneous microwave and cryoablation of lung metastases from adenoid cystic carcinoma (ACC) of the head and neck. This bi-institutional retrospective cohort study included 10 patients (6 females, median age 59 years [range 28–81]) who underwent 32 percutaneous ablation sessions (21 cryoablation, 11 microwave) of 60 lung metastases (median 3.5 tumors per patient [range 1–16]) from 2007 to 2019. Median tumor diameter was 16 mm [range 7–40], significantly larger for cryoablation (22 mm, p = 0.002). A median of two tumors were treated per session [range 1–7]. Technical success, local control, complications, and overall survival were assessed. Primary technical success was achieved for 55/60 tumors (91.7%). Median follow-up was 40.6 months (clinical) and 32.5 months (imaging, per tumor). Local control at 1, 2, and 3 years was 94.7%, 80.8%, and 76.4%, respectively, and did not differ between ablation modalities. Five of fifteen recurrent tumors underwent repeat ablation, and secondary technical success was achieved in four (80%). Assisted local tumor control at 1, 2, and 3 years was 96.2%, 89.8%, and 84.9%, respectively. Complications occurred following 24/32 sessions (75.0%) and 57.2% Common Terminology Criteria for Adverse Events (CTCAE) lower than grade 3. Of 13 pneumothoraces, 7 required chest tube placements. Hemoptysis occurred after 7/21 cryoablation sessions, and bronchopleural fistula developed more frequently with microwave (p = 0.037). Median length of hospital stay was 1 day [range 0–10], and median overall survival was 81.5 months (IQR 40.4–93.1). Percutaneous computed tomography-guided microwave and cryoablation can treat lung metastases from ACC of the head and neck. Complications are common but manageable, with full recovery expected.