RADIOFREQUENCY AND CRYOABLATION FOR MALIGNANT LUNG NODULES IN A COMMUNITY SETTING

Abstract

SESSION TITLE: Procedures Posters SESSION TYPE: Original Investigation Posters PRESENTED ON: October 18-21, 2020 PURPOSE: Localized ablative therapies such as radiofrequency ablation (RFA) and cryoablation (CA) are now accepted treatment modalities for malignant lung lesions, especially for those who are not candidates for surgery or radiotherapy. In this study, we present our experience in two community centers in utilizing ablative lung therapies. METHODS: A retrospective chart and image review was performed of patients treated with lung ablative therapies between November 2014 and September 2019. Outcomes were collected through February 2020. RFA utilized Boston Scientific LeVeen electrodes of sizes 3(13), 3.5(7) and 4 (1). CA was done using one (6) or two (11) Boston Scientific Galil probes. Our primary outcome was local recurrence free survival (RFS), defined as recurrence in the ablation zone or in the same segment. RESULTS: 25 (11 male) patients age 66 (SD 8) underwent ablation for 38 malignant nodules. 20 patients had 25 primary lung malignancies (16 adenocarcinoma, 9 squamous) and 5 patients had 13 metastatic nodules. The metastases were from colon (2), lung, leiomyosarcoma and nasopharyngeal carcinoma. 21 lesions (13 primary) were treated with RFA and 17 lesions (12 primary) were treated with CA. 10 procedures (26%) resulted in pneumothorax and 6 (15%) required chest tube placement. 31 patients (82%) were discharged same day or within 24 hours. Median follow-up was 25 months (range 6-63). The mean lesion size was 17mm (95% CI ± 2.9). Index lesion size was similar in RFA (16.3 ± 3.7) and CA (17.9 ± 4.5mm) groups. In the CA group there were 12% (2/17) local recurrences, whereas the RFA group had 29% (6/21) recurrences (p=0.26). Index lesion size for local recurrences was 16.3 ± 4.8mm in the RFA group and 21 ± 7.8mm in the CA group. There were 0 local recurrences with CA of primary tumors <2cm in diameter. There was no significant difference in local mean RFS time between RFA (33 ± 3.1 months) and CA groups (31.9 ± 2.7 months). Two-year local RFS rate was 79.5% in the RFA group vs 85.6% in the CA group (p=0.63). There were no deaths in the CA group, however the RFA group had 3 mortalities (p=0.1089). CONCLUSIONS: This study shows that ablative therapies can be utilized safely and effectively in a community center for stage I NSCLC and metastatic disease. Our outcomes are comparable to the Alliance trial in terms of local RFS and adverse events. This comprehensive evaluation of our experience with ablative procedures was not powered to detect differences in treatment groups between CA and RFA. However, CA tends to show a better outcome than RFA in our experience. Differences can be due to small sample size, low event rates, cofounders and selection bias. CLINICAL IMPLICATIONS: Our case series highlights the success and feasibility of local ablation for low-grade NSCLC and metastatic disease in a community setting. Further randomized control trials are required to prove superiority of one method over the other. DISCLOSURES: No relevant relationships by Gerard Berry, source=Web Response No relevant relationships by Francis Brahmakulam, source=Web Response No relevant relationships by Michael DiRico, source=Web Response No relevant relationships by shambo guha roy, source=Web Response