Postirradiation otitis media with effusion in nasopharyngeal carcinoma patients treated by intensity-modulated radiotherapy

Investigating the epidemiological relevance of secretory otitis media and neighboring organ diseases through an Internet search

Background

This study examined the epidemiological correlations between secretory otitis media (SOM) and diseases of neighboring organs. We measured changes in disease incidences during the 2020 COVID-19 pandemic using Internet big data spanning from 2011 to 2021.

Methods

This study used the Baidu Index (BI) to determine the search volume for the terms "secretory otitis media (SOM)", "tonsillitis", "pharyngolaryngitis", "adenoid hypertrophy (AH)", "nasopharyngeal carcinoma (NPC)", "nasal septum deviation (NSD)", "rhinosinusitis", "allergic rhinitis (AR)", and "gastroesophageal reflux disease (GERD)" in Mandarin from January 2011 to December 2021. The correlations between these terms were analyzed using Spearman's correlation coefficients. The results were compared search data from 2019 and 2021 to assess the effects of isolation on SOM in 2020.

Results

The seasonal variations trends of SOM and other diseases coincided well (P < 0.05), except for AR. During the 11-year timeframe, the monthly searches for rhinosinusitis, NSD, tonsillitis, pharyngolaryngitis, and NPC were statistically correlated with SOM (R = 0.825, 0.594, 0.650, 0.636, 0.664, respectively; P < 0.05). No correlation was found between SOM and AR, SOM and AH, or SOM and GERD (R =  - 0.028, R = 0.259, R = 0.014, respectively, P > 0.05). The total search volumes for SOM, rhinosinusitis, NPC, and AH decreased in 2020 compared to 2019.

Discussion

SOM exhibited a discernible epidemiological connection with rhinosinusitis, nasal septal deviation (NSD), tonsillitis, pharyngolaryngitis, and nasopharyngeal carcinoma (NPC). A decrease in public gatherings was observed to effectively reduce the incidences of SOM. This underscores the pivotal role of social measures in influencing the prevalence of SOM and emphasizes the intricate interplay between SOM and various associated health factors, with implications for public health strategies.

Endoscopic Endonasal Transpterygoid Approach and the Need for Myringotomy

OBJECTIVE

The expanded endonasal transpterygoid approach (EETA) is used to access the middle and posterior fossa through the pterygoid process. Traditionally, the eustachian tube (ET) was resected during EETA, which often required subsequent myringotomy for inner ear drainage. Anterolateral transposition of the ET was proposed to decrease potential morbidity associated with resection. However, a comparison of resection versus transposition regarding the need for subsequent myringotomy has not been reported.

METHODS

This is a retrospective cohort study of patients who underwent an EETA. Patient demographics, tumor characteristics, management of ET with resection versus transposition, and need for subsequent myringotomy were collected. Analysis was performed with JMP software in standard fashion and univariate and multivariate logistic regression analysis performed with a p < 0.05 was considered significant.

RESULTS

Ninety-one patients underwent EETA for various malignant and benign tumors. Twenty-seven patients required myringotomy, with tumors of the pterygopalatine fossa accounting for the most common location (n = 8). Malignant pathology had the highest myringotomy rate compared to benign tumors (48.9% vs. 10.9%, p < 0.001), as did receiving postoperative radiation (p < 0.001), ET resection (p < 0.001), and increasing CPK class. Multivariate analysis of these variables suggests that only ET resection significantly correlated with the need for myringotomy (LR 7.97, p = 0.005).

CONCLUSIONS

ET resection during EETA can lead to ET dysfunction and require myringotomy post-operatively, and patients should be counseled of this risk. Radiation treatment, malignant pathology, and CPK class, all reflecting situations where more extensive surgery was needed, were associated with the need for myringotomy on univariate analysis but did not reach significance with multivariate analysis.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:1203-1207, 2024.

Endoscopic endonasal recanalization of the obliterated eustachian tube via ureteral stent

KEY POINTS

Eustachian tube recanalization is a feasible procedure but additional studies are needed to determine its safety. Eustachian tube closure can result from different etiologies and can cause severe symptoms. Ureteral stents have appropriate shape and pliability for placement and long-term healing. Multidisciplinary team approach allows for simultaneous endonasal and otologic approaches.

Reconstruction of the Obliterated Eustachian Tube: A Pilot Case Series

OBJECTIVE

To investigate the safety and early efficacy of a procedure for reconstruction of the obliterated Eustachian tube (ET).

STUDY DESIGN

Retrospective case series.

METHODS

Patients with total obliteration of the cartilaginous ET, with intractable mucoid effusion causing repeated occlusion of tympanostomy tubes were included. Patients underwent endoscopic transnasal/transoral reconstruction of the obliterated ET using transtympanic illuminated guidewire guidance. A temporary stent (angiocatheter filled with bonewax) was placed to maintain patency while healing. In four cases an additional steroid-eluting propel stent was placed in the ET orifice. Main outcome measures were otomicroscopy results, absence of middle ear effusion, and nasopharyngoscopy showing patency of the ET orifice.

RESULTS

Nine ETs (seven patients), ages 17-68 years (mean 37.9) underwent ET reconstruction. Follow-up ranged from 4 to 56 months (mean 30.9 months). 89% of operated ears had no effusion at last follow-up. Two patients (three Eustachian tubes) underwent successful reoperation. There were no complications directly related to the procedure. Etiologies of obliteration included scarring after sinus surgery, obstruction after maxillo-mandibular advancement surgery (two patients), bullous pemphigus, gunshot trauma, and previous patulous obliteration (two patients).

CONCLUSIONS

Complete occlusion of the cartilaginous ET can be associated with intractable mucoid effusion; endoscopic examination should be considered in such cases. In this pilot study, ET reconstruction was found to be a safe and possibly effective procedure in patients with total obliteration of the ET from various etiologies. Larger studies with long term follow up are indicated.

LEVEL OF EVIDENCE

4 Laryngoscope, 2022.

Effect of Hydrogen Inhalation Therapy on Hearing Loss of Patients With Nasopharyngeal Carcinoma After Radiotherapy

Objective

To evaluate the clinical efficacy and safety of hydrogen inhalation in improving hearing loss in patients with long-term survival of nasopharyngeal carcinoma after radiotherapy.

Methods

The eustachian tube dysfunction score, pure tone air conduction threshold, bone conduction threshold, the score of tympanogram and otoscope were prospectively observed in patients with deafness after radiotherapy only or combined radiotherapy and chemotherapy for nasopharyngeal carcinoma. Paired t test and one-way analysis of variance were used to analyze the data before and after treatment.

Results

A total of 17 patients were observed. The median time from radiotherapy to now was 228 months, and the median time from the diagnose of deafness to now was 92 months. After 4 weeks of hydrogen inhalation, the score of eustachian tube dysfunction, air conduction and bone conduction hearing thresholds were significantly reduced, P values were 0.0293, 0.0027, 0.0404, respectively. The mean air-bone gap, the score of otoendoscopy and tympanogram were also decreased, but the differences were not significant (P = 0.2079, P = 0.0536, P = 0.1056). Patients with radiotherapy alone and concurrent chemo-radiotherapy had significantly lower air conduction hearing threshold after hydrogen absorption (P = 0.0142, P = 0.0495). The results of air and bone hearing thresholds before, 4 and 12 weeks after hydrogen inhalation showed a descending trend. The air and bone hearing thresholds before hydrogen inhalation were 74.69 ± 27.03 dB and 45.70 ± 21.58 dB, respectively. At the 12th week, the mean values of air and bone hearing thresholds were the lowest, which were 66.88 ± 20.88 dB and 40.94 ± 18.93 dB, respectively, but there was no significant difference in air and bone hearing thresholds among all groups (P = 0.6755, P = 0.7712). After hydrogen inhalation treatment, no adverse reactions such as nosebleed, chest pain, dyspnea, nausea, vomiting, dizziness, earache and allergic reaction were observed.

Conclusion

This is the first prospective study on the effect of hydrogen inhalation on hearing improvement in patients with deafness after radiotherapy/chemotherapy for nasopharyngeal carcinoma, suggesting that continuous hydrogen inhalation may be an alternative rehabilitation therapy for these patients.

Assessment of radiation-induced otitis media in patients with parotid gland malignancy

BACKGROUND

Otitis media with effusion (OME) is a known side effect of radiation therapy in patients with head and neck cancer.

AIMS/OBJECTIVES

To investigate the incidence rate and clinical course of radiation-induced OME, we have reported on the long-term characteristics of OME in patients with parotid gland malignancy.

MATERIAL AND METHODS

This cohort study assessed 200 patients who underwent post-parotidectomy radiation therapy from January 2010 to December 2019 in a tertiary referral center. Postoperative radiation therapy was performed at 6 weeks post-surgery. Serial magnetic resonance images were collected to detect otitis media. Two blinded otologists individually assessed data from radiation therapy initiation to 36 months of post-radiation therapy.

RESULTS

A total of 121 patients were enrolled (male, 61 [50.4%]; mean age, 46.98 ± 15.69 years), of which 14 developed otitis media (11.6%) within 6 months after radiation therapy. Spontaneous remission occurred without intervention within 1 year, excluding one patient who sustained otitis media for 2 years.

CONCLUSIONS AND SIGNIFICANCE

Radiation-induced OME occurred in 11.6% of patients and it remitted within 1 year without intervention. Therefore, cooperation between otolaryngologists and radiation oncologists is required and invasive intervention should be considered with careful risk-benefit evaluation.

Simultaneous Reduction of Volume and Dose in Clinical Target Volume for Nasopharyngeal Cancer Patients

PURPOSE

To compare the treatment outcome and severe late adverse effects (AEs) between conventional volume and dose (CVD) and simultaneously reduced volume and dose (SRVD) of clinical target volume treatments in patients with nasopharyngeal carcinoma.

METHODS AND MATERIALS

This retrospective cohort study enrolled patients with nonmetastatic stage II to IV nasopharyngeal cancer from a single institute. Survival endpoints and severe (≥grade 3) late AEs and comorbidity were compared between groups. The correlation of severe late AEs, comorbidity, and overall survival (OS) were evaluated using Kaplan-Meier and Cox regression methods.

RESULTS

From January 2012 to June 2017, this study enrolled 178 patients, 64 in the CVD group and 114 in the SRVD group. The 2 groups did not differ significantly in patient characteristics except for mean follow-up time (37.6 vs 48.8 months; P = .01). The SRVD group did not significantly differ from the CVD group in local control survival (82.0% vs 78.4%; P = .85), regional control survival (89.9% vs 86.0%; P = .62), or disease-free survival (76.4% vs 66.9%; P = .67). The SRVD group had significantly better OS (93.9% vs 67.0%; P < .001) and salvage survival (79.3% vs 20.7%; P < .01) and a significantly lower ratio of severe lung infection (1 of 113 vs 5 of 59; P = .02). The SRVD group had a significantly lower risk of mortality (hazard ratio [HR], 0.3; P = .03). The factors associated with a significantly higher risk of mortality were N3 (regional lymph node stage status of N3) (HR, 3.0; P = .02); comorbidities of diabetes, coronary artery disease, or chronic kidney disease (grades 2-3) (HR, 3.8; P = .009), and severe lung infection (HR, 6.3; P = .007).

CONCLUSIONS

Simultaneously reduced volume and dose of clinical target volumes did not impair locoregional control or disease-free survival. The benefits of SRVD treatment may include significant reduction in severe late AEs, particularly lung infection, dysphagia, and xerostomia. However, additional studies with longer patient follow-up are required to confirm these benefits.

Intracranial aneurysms formation after radiotherapy for head and neck cancer: a 10-year nationwide follow-up study

Background

Intracranial aneurysms after radiotherapy (RT) have previously been reported. However, the majority of studies were case reports. Therefore, we performed a nationwide study to explore the risk of radiation-induced intracranial aneurysms.

Methods

This study included patients diagnosed with head and neck cancer (ICD9: 140–149, 161). Intracranial aneurysms formation was identified using the following ICD9 codes: nonruptured cerebral aneurysm (ICD9:4373), aneurysm clipping (ICD9:3951). Patients who did not receive curative treatment and those with intracranial aneurysms before the diagnosis of head and neck cancer were excluded.

Results

In total, 70,691 patients were included in the final analysis; they were categorized into the following three groups: nasopharyngeal carcinoma (NPC) with RT, non-NPC with RT, and non-NPC without RT. Patients in the NPC with RT group had the highest risk of developing intracranial aneurysms (hazard ratio (HR) 2.57; P <  0.001). In addition, hypertension was also a risk factor of developing intracranial aneurysms (HR 2.14; P <  0.01). The mean time interval from cancer diagnosis to intracranial aneurysm formation in the NPC with RT group was 4.3 ± 3.1 years.

Conclusions

Compared with the non-NPC with RT and the non-NPC without RT groups, patients with NPC who received RT had a higher risk of developing intracranial aneurysms.

Effect of vascular endothelial growth factor and its receptors in adult otitis media with effusion

PURPOSE

Some studies have demonstrated that vascular endothelial growth factor (VEGF) plays a critical role in the pathogenesis of otitis media with effusion (OME) in animal models. However, the levels of VEGF and its receptors in adult OME have not been clarified. Our study was designed to detect the levels of VEGF and its receptors in adult OME and explore their relationship with effusion types, duration and prognosis of OME.

METHODS

61 patients with secretory otitis media were enrolled including 21 males and 40 females, with an average age of 54.7 ± 17.5 years. The middle-ear effusions were collected by tympanocentesis or myringotomy. The protein concentrations were determined by enzyme-linked immunosorbent assay and messenger RNA by real-time quantitative PCR.

RESULTS

VEGF level was higher in AOME group, but not correlated with the recurrence of OME. VEGFR1 and VEGFR2 levels were lower in recurrent group compared with non-recurrent group. VEGFR2 level was higher in serous effusions than mucoid effusions. VEGF messenger RNA was positively correlated both with HIF-1α and MUC5B.

CONCLUSIONS

VEGF and its receptors function to induce the production of middle-ear effusions (MEEs) at acute stage of OME rather than chronic or recurrent stage, which is mainly mediated by HIF-1α pathway. The formation of mucoid effusions is associated with MUC5B and VEGFR2, but not with duration and recurrence of OME.

Dosimetric parameters associated with conductive or sensorineural hearing loss 5 years after intensity-modulated radiation therapy in nasopharyngeal carcinoma

BACKGROUND

Most previous studies are separate dosimetric analyses of conductive or sensorineural hearing loss, and they are not conducive to a comprehensive assessment of auditory radiation damage.

AIMS/OBJECTIVES

Our study aimed to evaluate the long-term incidence of sensorineural hearing loss (SNHL) or conductive hearing loss (CHL) in patients with nasopharyngeal carcinoma (NPC) after intensity-modulated radiation therapy (IMRT), and to investigate the relationship between SNHL or CHL and patient factors, treatment-related factors, and radiation dose parameters.

MATERIAL AND METHODS

Seventy patients (117 ears) with NPC, who were also treated with IMRT in our hospital from 2006 to 2014, were retrospectively analyzed. Radiation doses to the Eustachian tube (ET), middle ear (ME), cochlear (Co), and internal auditory canal (IAC) were assessed. Pure tone audiometry and impedance audiometry were performed before and during the follow-up period. The relationships between low-frequencies (0.5-2 kHz) or high-frequency (4 kHz) SNHL/CHL and radiotherapy dose parameters were analyzed.

RESULTS

Of the 117 ears studied, 7.69% had low-frequency SNHL, 35.9% had high-frequency SNHL, 23.93% had low-frequency CHL, and 18.80% had high-frequency CHL. The incidence of high-frequency CHL was higher in the T4 group than in the T (1-3) group (p < .05). When IAC D_max > 42.13 Gy or IAC D_mean > 32.71 Gy, the risk of high-frequency SNHL increased in NPC patients. When ME D_max > 44.27 Gy, ME D_mean > 29.28 Gy, or ET D_max > 57.23 Gy, the risk of high-frequency CHL in NPC patients increased.

CONCLUSIONS AND SIGNIFICANCE

SNHL and CHL remain common ear complications after IMRT for NPC. IAC D_max, IAC D_mean, ME D_max, ME D_mean, and ET D_max all need to be carefully considered during the IMRT treatment protocol.

Cochlea sparing with a stratified scheme of dose limitation employed in intensity-modulated radiotherapy for nasopharyngeal carcinoma: A dosimetry study

Hearing loss is 1 of the major complications after radiotherapy in nasopharyngeal carcinoma (NPC) patients, how to minimize dose to cochlea in order to reduce the incidence of sensorineural hearing loss is a critical task. This study is to investigate a stratified scheme of cochlea sparing based on T stage in intensity-modulated radiotherapy. We designed a comparison between 2 plans of cochlea sparing plan (C-Plan) and regular noncochlea sparing plan (R-Plan) from 19 NPC patients with 2, 3, 8, and 6 cases of T1, T2, T3, and T4 stage, respectively. The outcomes showed that target coverage parameters and dose-volume histogram features were of no significant difference, with a significant difference in dose distribution between C-Plan and R-Plan in cochlea and eustachian, e.g., ipsilateral cochlea D_mean 4619.75 ± 1134.09 cGy in C-Plan and 5061.03 ± 1121.09 cGy in R-Plan (p = 0.000), contralateral cochlea D_mean 4386.73 ± 945.14 cGy in C-Plan and 4991.38 ± 961.21 cGy in R-Plan (p = 0.000). Meanwhile, there was no significant difference in dose distribution in spinal cord, brainstem, and other OARs. Our dosimetry study showed cochlea sparing in intensity-modulated radiotherapy for NPC reduced cochlea dose to different extent, so we suggested a stratified scheme of cochlea sparing based on T stage could be a useful and practical tool for both physicists and radiation doctors.

Otitis media with effusion after radiotherapy of the head and neck: a systematic review

BACKGROUND

Otitis media (OM) and associated hearing problems may be side effects to radiotherapy of the head and neck region and affect patient quality of life. The condition is associated with the tumor location.

OBJECTIVE

To perform a systematic review concerning the present knowledge of the risk of OM after radiotherapy of the head and neck.

METHODS

A comprehensive search of PubMed and Embase was carried out between 1 October 2015 and 6 February 2017. The search strategy followed the PRISMA guideline for systematic reviews.

RESULTS

Of 597 articles 11 fulfilled the inclusion criteria. Seven were retrospective and four prospective. There were no randomized controlled trials. Eight studies concerned nasopharyngeal cancer. One study concerned cancer of the parotid gland and two studies concerned other locations of head and neck cancer. Meta-analysis could not be done due to heterogeneity between the studies. The incidence of OM varied considerably (range 8-29%).

CONCLUSIONS

The incidence of OM is high after radiotherapy of cancer of the upper head and neck area and the Eustachian tube (ET) irradiation dosage seems associated with development of OM, but the literature is poor. Research is needed to designate patients at risk of developing OM after radiotherapy. Preferably through analysis of dosage relationships between the ET and middle ear, and development of OM. Reporting of OM should be per ear and follow standardized protocols of middle ear assessment before and after radiotherapy. Furthermore, there is a need to find new ways to prevent and treat radiation-induced OME, preferably through randomized controlled trials.

Relationship between Eustachian tube dysfunction and otitis media with effusion in radiotherapy patients

Objective:

This study evaluated the relationship between radiation and Eustachian tube dysfunction, and examined the radiation dose required to induce otitis media with effusion.

Methods:

The function of 36 Eustachian tubes in 18 patients with head and neck cancer were examined sonotubometrically before, during, and 1, 2 and 3 months after, intensity-modulated radiotherapy. Patients with an increase of 5 dB or less in sound pressure level (dB) during swallowing were categorised as being in the dysfunction group. Additionally, radiation dose distributions were assessed in all Eustachian tubes using three dose–volume histogram parameters.

Results:

Twenty-two of 25 normally functioning Eustachian tubes before radiotherapy (88.0 per cent) shifted to the dysfunction group after therapy. All ears that developed otitis media with effusion belonged to the dysfunction group. The radiation dose threshold evaluation revealed that ears with otitis media with effusion received significantly higher doses to the Eustachian tubes.

Conclusion:

The results indicate a relationship between radiation dose and Eustachian tube dysfunction and otitis media with effusion.

The effectiveness of myringotomy and ventilation tube insertion versus observation in post-radiation otitis media with effusion

To compare the effectiveness of myringotomy and ventilation tube insertion versus observation in post-radiation otitis media with effusion (OME) in nasopharyngeal carcinoma (NPC). NPC patients who finished radiotherapy and had persistent OME were randomized to myringotomy and ventilation tube insertion and observation groups. The resolution rate of OME and hearing outcomes were evaluated. Forty three patients (23 in control group and 20 in intervention group) were analyzed. One patient in the control group obtained a resolution of OME. The remaining patients in the control group had persistent middle ear fluid. Fourteen patients in the intervention group had retained ventilation tubes without otorrhea. Ventilation tubes had spontaneously extruded in the remaining six patients and all of these patients had recurrent OME. Mean air-pure tone average in the control group was 52.04 dB (SD 11.61), significantly different from the intervention group [38.15 dB (SD 19.10); p = 0.01]. Mean air-bone gap in the control and intervention groups were 27.30 dB (SD 9.11) and 9.30 dB (SD 9.59) respectively (p < 0.001). Mean air-pure tone average and mean air-bone gap improvement was significantly improved in the intervention group (p < 0.001). Two patients in the intervention group (10%) developed complications, one patient suffering suppurative otitis media whilst another had otorrhea, which resolved after 1-week course of antibiotic treatment. Post-radiation OME is common in patients with NPC and tends to persist long-term. Conservative management is safe, however, is plagued by frustrating effects of hearing impairment and aural fullness. Myringotomy with ventilation tube insertion leads to hearing improvement with few complications.

Complications of tympanostomy tubes in head and neck cancer patients

PURPOSE

To assess myringotomy plus tympanostomy tube (MTT) complication rates in head and neck cancer (HNC) patients with otitis media (OM).

MATERIALS AND METHODS

We performed a retrospective review of 182 HNC patients with OM treated between January 2000 and October 2007 for demographic data and data about MTT-related complications, tumor type and outcomes following MTT.

RESULTS

We identified OM in 35 nasopharyngeal (NP), 34 paranasal sinus (PNS), and 24 larynx cancer patient ears; of these, 29 (83%), 31 (91%), and 22 (92%), respectively, were treated with MTT. Of the 29 NP cancer patient ears treated with MTT, 13 (45%) received MTT before radiotherapy; complications included otorrhea in 11 ears (38%), otorrhea with perforation in 3 ears (10%), and cholesteatoma in 1 ear (3%). Of the 31 PNS cancer patient ears treated with MTT, 17 (55%) received MTT before radiotherapy; complications included otorrhea in 10 ears (32%) and otorrhea with perforation in 3 ears (10%). All 22 laryngeal cancer patient ears were treated with MTT before radiotherapy; 5 ears (23%) developed chronic otorrhea. Patients with pre-existing eustachian tube dysfunction had significantly higher rates of tympanostomy tube otorrhea (p=.009).

CONCLUSIONS

The complication rates of OM in the setting of NP or PNS cancer were not significantly different regardless of intervention timing in relation to radiotherapy. Laryngectomy patients had a high rate of tympanostomy sequelae after radiotherapy. MTT for OM has high complication rates in HNC patients.

Aetiology and pathology of otitis media with effusion in adult life

OBJECTIVES

To gather and analyse information concerning the aetiology and pathology of otitis media with effusion in adults.

METHOD

A review of the English language literature from 1970 to the present was conducted.

RESULTS

The available evidence suggests that otitis media with effusion in adult life is best viewed as a syndrome with a number of causes, including: infiltration of the eustachian tube by nasopharyngeal carcinoma and other local malignancies; changes in the middle ear and eustachian tube induced by radiotherapy; and systemic disease.

CONCLUSION

There is now a body of evidence specifically related to the aetiology and pathology of otitis media with effusion in adult life. However, further research is required to fill in the gaps in our knowledge and understanding of this condition.

Predictors of Mastoiditis after Intensity-Modulated Radiotherapy in Nasopharyngeal Carcinoma: A Dose-Volume Analysis

Background: To identify predictors for development of mastoiditis after intensity-modulated radiation therapy (IMRT) in nasopharyngeal carcinoma (NPC).

Methods: Data for 146 NPC patients treated with IMRT was retrospectively reviewed under institutional ethics committee approval. Clinical factors associated with mastoiditis were analyzed. Dose-volume histogram analysis was performed for the Eustachian tube, tympanic cavity, mastoid air cells, cochlea, internal auditory canal and vestibular apparatus to relate doses to radiographic changes in the mastoid. Mastoiditis was assessed using magnetic resonance imaging and was classified as Grade 0 (none), 1 (mild), 2 (moderate) or 3 (severe); Grade 3 mastoiditis was the study end-point.

Results: Eighty-eight ears (36%) had radiation-induced mastoiditis: 38/244 (15.6%) mastoid complexes had Grade 1-2 mastoiditis and 50/244 (20.5%) mastoid complexes had Grade 3 mastoiditis. Multivariate analysis revealed a mastoid mean dose > 35.93 Gy (odds ratio [OR]=4.22, P=.003), Eustachian tube mean dose > 53.43 Gy (OR=2.16, P=.034) and advanced T category (T3 and T4; OR=10.33, P=.032) were negative prognostic factors for Grade 3 mastoiditis.

Conclusions: Radiation-induced mastoiditis remains a common late toxicity in NPC after radiotherapy. The mean dose to the mastoid air cells and Eustachian tube should be limited to reduce the risk of radiation-induced mastoiditis.

Dose-volume factors associated with ear disorders following intensity modulated radiotherapy in nasopharyngeal carcinoma

This study is to identify significant dosimetric parameters for ear disorders in nasopharyngeal carcinoma (NPC) patients treated with intensity modulated therapy only. Ninety-seven patients with NPC were retrospectively reviewed. Organs at risk (OARs) in the auditory apparatus were contoured. Dose-volume histogram parameters were generated for the Eustachian tube (ET), tympanic cavity (TC), mastoid air cells, vestibular apparatus, cochlea and internal auditory canal (IAC). Ear disorders were rated 0 (none), 1 (mild) or 2 (severe) by a clinician blinded to radiation doses; Grade 2 ear disorders was the study end-point. Multivariate analysis revealed ET.D30 (dose to 30% of ET volume) >52.75 Gy and M.D0.5CC (dose to 0.5 ml of mastoid volume) >41.04 Gy (OR = 3.77, P = 0.012 and OR = 1.27, P = 0.033, respectively) were associated with Grade 2 ear disorders. Our results demonstrated that post-irradiation ear disorders remain a common late toxicity in NPC after IMRT. ET.D30 and M.D0.5CC should be considered during IMRT treatment plan optimization, review and approval.

Incidence of and Risk Factors for Mastoiditis after Intensity Modulated Radiotherapy in Nasopharyngeal Carcinoma

PURPOSE

To report the incidence of and risk factors for mastoiditis after intensity-modulated radiotherapy (IMRT) in nasopharyngeal carcinoma (NPC).

PATIENTS AND METHODS

Retrospective analysis of pretreatment and follow-up magnetic resonance imaging (MRI) data for 451 patients with NPC treated with IMRT at a single institution. The diagnosis of mastoiditis was based on MRI; otomastoid opacification was rated as Grade 0 (none), 1 (mild), 2 (moderate) or 3 (severe) by radiologists blinded to clinical outcome. This study mainly focused on severe mastoiditis; patients were divided into three groups: the G0M (Grade 0 mastoiditis before treatment) group, G1-2M (Grade 1 to 2 mastoiditis before treatment) group and G3M (Grade 3 mastoiditis before treatment) group. The software SAS9.3 program was used to analyze the data.

RESULTS

For the entire cohort, the incidence of Grade 3 mastoiditis was 20% before treatment and 31%, 19% and 17% at 3, 12 and 24 months after radiotherapy, respectively. In the G0M group, the incidence of severe mastoiditis was 0% before treatment and 23%, 15% and 13% at 3, 12 and 24 months after radiotherapy, respectively. Multivariate analysis revealed T category (OR=0.68, 95% CI = 0.469 to 0.984), time (OR=0.668, 95% CI = 0.59 to 0.757) and chemotherapy (OR=0.598, 95% CI = 0.343 to 0.934) were independent factors associated with severe mastoiditis in the G0M group after treatment.

CONCLUSIONS

Mastoiditis, as diagnosed by MRI, occurs as a progressive process that regresses and resolves over time in patients with NPC treated using IMRT.

External auditory canal cholesteatoma in patients given radiotherapy for nasopharyngeal carcinoma

BACKGROUND

Patients who undergo radiotherapy (RT) for nasopharyngeal carcinoma (NPC) may develop external auditory canal cholesteatoma (EACC).

METHODS

The records of patients with newly diagnosed NPC who had received concomitant chemotherapy and RT in a tertiary referral center from 1997 January to 2012 July were retrospectively reviewed.

RESULTS

RT-related external auditory canal cholesteatoma (RT-related EACC) was identified in 15 of 833 patients given RT for NPC. Three patients had EACC in both ears. The interval from completion of RT to the diagnosis of EACC ranged from 0.5 to 15.4 years (mean, 5.6 years). RT-related EACC commonly (75%) invaded the anterior and inferior parts of the external canal wall. Canaloplasty was used in 12 patients to surgically remove cholesteatoma. There was no recurrence of RT-related EACC during the study period.

CONCLUSION

Patients with NPC might contract RT-related EACC a few years after RT. We hypothesize that a fraction dose of 200 cGy or more induces RT-related EACC.