Inflammation following invasive procedures for Warthin's tumour: A retrospective case series

A Safety and Feasibility Trial of Ultrasound-Guided Radiofrequency Ablation of Parotid Warthin's Tumor

OBJECTIVE

To determine if ultrasound-guided (USG) radiofrequency ablation (RFA) of Parotid Warthin's tumor under local anesthesia is a safe and effective procedure.

STUDY DESIGN

Safety and feasibility study.

SETTING

Tertiary academic medical center.

METHODS

This is an IDEAL phase 2a trial in a tertiary referral center. Twenty patients with Parotid Warthin's tumor were recruited. RFA was done between September and December 2021 for all 20 patients using a CoATherm AK-F200 machine with a disposable, 18G × 7 mm radiofrequency electrode. Results and follow-up statistics were compared with a historic sample of patients with parotid Warthin's tumor who underwent parotidectomy between 2019 and 2021 in the same center.

RESULTS

Nineteen patients were included in the analysis as 1 patient dropped out after 4 weeks of follow-up. The mean age for the RFA group was 67 years old with most of them being male smokers. At a median of 45 weeks (44-47 weeks) postprocedure there was a 7.48 mL (68.4%) volume reduction compared to baseline. Three patients had transient facial nerve (FN) paresis, 1 recovered within hours, and the other 2 by 12 weeks follow-up. Three patients had great auricular nerve numbness; 1 patient had infected hematoma treated in an out-patient manner. Compared to a historic cohort of parotidectomy patients for Warthin's tumor, there was no significant difference in FN paresis and other minor complications between the 2 treatment modalities.

CONCLUSION

The current analysis suggests that USG RFA of Warthin's Tumor is a safe alternative to parotidectomy with shorter operative time and length of stay.

Long-Term Outcomes of Radiofrequency Ablation for Treatment of Cystic Warthin Tumors versus Solid Warthin Tumors

Background: To describe the long-term outcomes of radiofrequency ablation (RFA) of parotid Warthin tumors that have different consistencies and locations. Methods: We reviewed ten patients with Warthin tumors undergoing RFA treatment from 2016 to 2019. The mean follow-up was 24.3 ± 13.1 months (range 7–42 months). Results: RFA was performed on 11 tumors in ten patients. Cystic tumors (n = 4) had better volume reduction ratios (VRR) than solid tumors (n = 7) at month one and month six, following RFA (77.9% vs. 47.3%, 95.1% vs. 80.6%, respectively, p = 0.003). Tumors in both superficial lobes and deep lobes (n = 7) were larger than tumors in superficial lobes alone (n = 4), though there was no difference in VRR after treatment. All residual tumors were found in superficial lobes. There was no increase in residual tumor size. Every patient showed marked cosmetic improvements, with visible tumors becoming non-palpable masses. Conclusions: RFA is a safe and effective treatment for Warthin tumors, with better volume reduction in cystic tumors. Results remained satisfying over the long-term for all residual tumors found in superficial lobes, making it easier for re-intervention if necessary.

The growth rate and the positive prediction of needle biopsy of clinically diagnosed Warthin's tumor

PURPOSE

This study reports the clinical course, including the growth rate, of Warthin's tumor (WT) and evaluates the positive prediction of needle biopsy for WT.

METHODS

The medical records of 182 patients clinically diagnosed with WT were retrospectively reviewed. Tumor growth rates were measured in patients who underwent serial radiologic exams with minimum 6-month time intervals, and the positive prediction value (PPV) of needle biopsy was evaluated in comparison with surgical pathology in patients who underwent surgical excision of the tumors.

RESULTS

Serial radiologic exams were available for growth rate measurement in 31 tumors (size 0.7-9.1 cm) from 25 patients. Among these, 24 tumors increased in size, and 7 were stable. The median follow-up duration was 23.5 months [interquartile range (IQR) 14.8-51.9], and the tumor growth rate ranged from - 0.36 to 2.26 cm per year (median 0.26, IQR 0.07-0.44). Needle biopsy results were available for comparison with postoperative pathology specimens in 147 patients. The PPV was 97.7% for fine-needle aspiration biopsy and 100% for core-needle biopsy. There were no reports of inflammation, facial nerve paralysis, or admission event during the follow-up.

CONCLUSIONS

WT glows slowly and can be predicted by needle biopsy. Therefore, parotid masses diagnosed as Warthin's tumor can be treated or left untreated based on the patient's needs and clinical decision-making.