Pulsed Radiofrequency Ablation for the Treatment of Glossopharyngeal Neuralgia Secondary to Oropharyngeal Carcinoma

Abstract

Background: The management of glossopharyngeal neuralgia due to oropharyngeal carcinoma is particularly difficult because of rich innervations of the area, erosive nature of neoplasm and dynamic pain evoked by the functional movements like swallowing and chewing. Few case reports have shown the efficacy of pulsed radiofrequency (PRF) treatment in primary and secondary glossopharyngeal neuralgia in non-cancer patients. However, the efficacy of PRF ablation of the glossopharyngeal nerve in oral cancer patients is not known. Objectives: This study was conducted to evaluate the efficacy and safety of PRF ablation of the glossopharyngeal nerve for the management of oropharyngeal cancer pain involving the base of the tongue, tonsillar fossa, and oropharynx. Study Design: Prospective interventional clinical trial. Setting: Tertiary care hospital and medical education and research institute. Methods: A total of 25 adult patients suffering from oropharyngeal carcinoma, complaining of severe pain in the area mainly supplied by glossopharyngeal nerve, were included. The patients underwent fluoroscopy-guided PRF ablation of the glossopharyngeal nerve of the affected site 3 times at 42°C temperature for 120 seconds with 22-gauge, 10 cm long, 5 mm active tip radiofrequency needle. They were followed up for one year for pain relief, nausea-vomiting and sleep disturbances. The treatment was considered effective if there was 50% reduction in pain score at 2 weeks. Results: There was significant reduction in the overall pain score including site specific pain, odynophagia and ear pain after radiofrequency ablation (P < 0.0001) in all the patients. This was associated with decreased opioid consumption (P < 0.001), lesser nausea/vomiting, and improved sleep. The treatment was effective in 23 out of 25 patients (92%) for more than 3 months. No major complication was observed in any patient. The average duration of effective pain relief was 5 to 9 months. Limitations: Patients having bilateral glossopharyngeal neuralgia or an advanced stage of oral cancer with large lymph nodes at the angle of mandible were not included. This study was a singlecenter observational clinical trial and further multi-center, randomized, controlled trails are needed to obtain higher level of evidence. Conclusion: Our results showed that PRF ablation can be used effectively and safely for the treatment of glossopharyngeal neuralgia secondary to oropharyngeal carcinoma. Key words: Glossopharyngeal neuralgia, ear pain, odynophagia, oral cancer pain, pulsed radiofrequency ablation, side effects

<p>The Long-Term Outcome of CT-Guided Pulsed Radiofrequency in the Treatment of Idiopathic Glossopharyngeal Neuralgia: A Retrospective Multi-Center Case Series</p>

“…We evaluated the therapeutic effects of PRF in patients with idiopathic GPN and the results revealed that PRF could obtain a promising effect with an effective rate of 93.3% at 1 month postoperatively with long-term recurrence-free survival rates of 54.8% at 120 months postoperatively. The short-term efficacy we observed is consistent with that of Bharti et al, 26 who reported a study about GPN secondary to oropharyngeal carcinoma that was treated by PRF. In their study, the treatment was effective in 23 out of 25 patients (92%), for more than 3 months without major complications.…”

“…In their study, the treatment was effective in 23 out of 25 patients (92%), for more than 3 months without major complications. However, Bharti et al 26 reported that the average duration of effective pain relief was only 5 to 9 months. As a result, we speculate that PRF can attain longer duration of pain relief for the treatment of idiopathic GPN than secondary GPN.…”

“…In 2005, Abejón et al 25 performed PRF on 1 idiopathic GPN and 1 secondary GPN, in which the results revealed that the treatment was effective for both patients for over 6 months. Bharti et al 26 also showed the efficacy and safety of PRF on the treatment of GPN secondary to oropharyngeal cancer in a clinical trial with 25 sample sizes, and demonstrated that PRF was a beneficial treatment option for secondary GPN patients without serious complications. However, there is a scarcity of studies evaluating the longterm clinical outcomes of PRF in the management of idiopathic GPN patients.…”

<p>Application and Therapeutic Effect of Puncturing of the Costal Transverse Process for Pulsed Radiofrequency Treated T1-T3 Herpes Zoster Neuralgia</p>

“…Therefore, blocking the spinal ganglion can block the transmission of peripheral pain signals to the upper center, thereby inhibiting the release of excitatory transmitters and regulating changes in central plasticity. 16,17 In clinic, pulsed radiofrequency (PRF) of dorsal root ganglion (DRG) has been widely used in many diseases, such as knee osteoarthritis, 18,19 pubic neuralgia, 20 postherpetic neuralgia, 21 occipital neuralgia, 21 glossopharyngeal neuralgia, 22 etc, due to its advantages of less destructiveness, quick recovery, and obvious effect. 23 In recent years, the research on the mechanism of PRF has been carried out gradually.…”

Detailed Parameters and Accurate Description are Needed for Pulsed Radiofrequency

“…After intensively reading the recent article "Pulsed Radiofrequency Ablation for the Treatment of Glossopharyngeal Neuralgia Secondary to Oropharyngeal Carcinoma" written by Bharti et al (1), we were so excited to see the conclusion they made about the efficacy of pulsed radiofrequency (PRF), but we are really confused about the parameters of PRF treatment that they used during the procedure.…”