10.14639/0392-100X-N1107
Objective. Despite the increasing incidence rate of vestibular schwannomas (VS), controversies in their management are still present. Methods. A 35-item multiple-choice survey investigating the current practice patterns of VS care was sent to the members of the Italian Society of Otolaryngology, Head and Neck Surgery (SIO) and of the Italian Society of Neurosurgery (SINCH). Results. Among 66 respondents, 37 (56.0%) claimed to be actively involved in VS management. Most interviewees (35.1%) declared &gt; 20 years of experience and 59.5% claimed to work in an academic practice. The number of cases evaluated in each centre per year varied widely, with 54.0% evaluating &gt; 25 cases/year and only 13.6% &gt; 100 cases/year. Multidisciplinary care for VS evaluation was confirmed by 50.0% of respondents, and multidisciplinary surgical care by 62.2%. Observation and surgery were the most common management options proposed. Further details regarding VS care are presented. Conclusions. The present study provides the first overview on the current practice patterns of VS care in Italy. Although integrated in most centres, a multidisciplinary model of care needs to be encouraged. Wide heterogeneity in experience and practices is mostly influenced by the surgeon’s different specialties and by the lack of shared guidelines.
application/xml
1827-675X
1107
en
Diego Cazzador
https://creativecommons.org/licenses/by-nc-nd/4.0
ACTA Otorhinolaryngologica Italica
skull base surgery
Defining current practice patterns of vestibular schwannoma management in Italy: results of a nationwide survey
Text.Serial.Journal
https://www.actaitalica.it/
41
Vestibology
2021-05-05
2020-09-30
2021-05-17
2021-05-17
185-191
1
Elisabetta Zanoletti
2021/05/05
10.14639/0392-100X-N1107
185
Otolaryngology Section, Department of Neuroscience - DNS, Padua University, Padua, Italy; *D. Cazzador and E. Zanoletti contributed equally to this work
1827-675X
skull base surgery
en
191
Defining current practice patterns of vestibular schwannoma management in Italy: results of a nationwide survey
https://www.actaitalica.it/article/download/1107/550
41
ACTA OTORHINOLARYNGOLOGICA ITALICA 2021;41:185-191; doi: 10.14639/0392-100X-N1107




Vestibology


Defining current practice patterns of vestibular
schwannoma management in Italy:
results of a nationwide survey
L’attuale gestione dello schwannoma vestibolare in Italia: risultati di una survey nazionale
Nicola Quaranta1, Marco Pontrelli1, Sabino Ciprelli1, Francesco Signorelli2, Luca Denaro3, Domenico d’Avella3,
Giovanni Danesi4, Diego Cazzador5,6*, Elisabetta Zanoletti5*
1
  Unit of Otolaryngology, Department of BMS, Neuroscience and Sensory Organs, University of Bari, Italy; 2 Unit of Neurosurgery,
Department of BMS, Neuroscience and Sensory Organs, University of Bari, Italy; 3 Academic Neurosurgery, Department of
Neuroscience - DNS, Padova University, Padova, Italy; 4 ENT and Skull-Base Surgery Department, Department of Neurosciences,
Ospedale Papa Giovanni XXIII, Bergamo, Italy; 5 Otolaryngology Section, Department of Neuroscience - DNS, Padova University,
Padova, Italy; 6 Section of Human Anatomy, Department of Neuroscience - DNS, Padova University, Padova, Italy
*
  D. Cazzador and E. Zanoletti contributed equally to this work.


SUMMARY
Objective. Despite the increasing incidence rate of vestibular schwannomas (VS), contro-
versies in their management are still present.
Methods. A 35-item multiple-choice survey investigating the current practice patterns of
VS care was sent to the members of the Italian Society of Otolaryngology, Head and Neck
Surgery (SIO) and of the Italian Society of Neurosurgery (SINCH).
Results. Among 66 respondents, 37 (56.0%) claimed to be actively involved in VS manage-              Received: September 5, 2020
ment. Most interviewees (35.1%) declared > 20 years of experience and 59.5% claimed to               Accepted: October 13, 2020
work in an academic practice. The number of cases evaluated in each centre per year varied
widely, with 54.0% evaluating > 25 cases/year and only 13.6% > 100 cases/year. Multidis-             Correspondence
ciplinary care for VS evaluation was confirmed by 50.0% of respondents, and multidiscipli-           Diego Cazzador
nary surgical care by 62.2%. Observation and surgery were the most common management                 Otolaryngology Section, Department of Neuro-
                                                                                                     science - DNS, Padova University, via Giustiniani
options proposed. Further details regarding VS care are presented.
                                                                                                     2, 35128 Padova, Italy
Conclusions. The present study provides the first overview on the current practice patterns
                                                                                                     Tel. +39 049 8218778. Fax +39 049 8211994
of VS care in Italy. Although integrated in most centres, a multidisciplinary model of care          E-mail: diego.cazzador@unipd.it
needs to be encouraged. Wide heterogeneity in experience and practices is mostly influ-
enced by the surgeon’s different specialties and by the lack of shared guidelines.                   Funding
KEY WORDS: vestibular schwannoma, acoustic neuroma, microsurgery, stereotactic                       None.
radiotherapy, skull base surgery
                                                                                                     Conflict of interest
RIASSUNTO                                                                                            The Authors declare no conflict of interest.
Obiettivi. Nonostante il costante incremento di incidenza dello schwannoma vestibolare
(VS), non vi è ancora uniformità nella gestione di tale patologia.                                     How to cite this article: Quaranta N, Pontrelli
Metodi. Un questionario di 35 domande sulle strategie di trattamento del VS è stato sotto-             M, Ciprelli S, et al. Defining current practice
posto ai membri della SIO e della SINCH.                                                               patterns of vestibular schwannoma management
Risultati. Tra i 66 intervistati che hanno risposto al questionario, il 56,0% ha confermato di         in Italy: results of a nationwide survey. Acta
prendere parte attivamente nel trattamento dello VS. La maggioranza dei partecipanti (35,1%)           Otorhinolaryngol Ital 2021;41:185-191. https://
dichiarava > 20 anni di esperienza nel settore, e il 59,5% di lavorare in un contesto accademico.      doi.org/10.14639/0392-100X-N1107
Il 54,0% degli intervistati ha affermato di valutare > 25 casi/anno, mentre solo il 13,6% > 100
casi/anno. Il 50,0% ha dichiarato di valutare lo VS nell’ambito di un gruppo multidisciplinare,      © Società Italiana di Otorinolaringoiatria
mentre il 62,2% di operare in un contesto multidisciplinare. L’approccio conservativo e la chirur-   e Chirurgia Cervico-Facciale
gia si confermavano le strategie terapeutiche più frequentemente proposte.
Conclusioni. Lo studio presenta una prima panoramica sulle strategie di trattamento dello                           OPEN ACCESS
VS in Italia. Nonostante un modello multidisciplinare di gestione dello VS sia già diffuso in        This is an open access article distributed in accordance with
molti centri, è necessario incrementarne ulteriormente lo sviluppo. Le diverse specializza-          the CC-BY-NC-ND (Creative Commons Attribution-Non-
                                                                                                     Commercial-NoDerivatives 4.0 International) license. The
zioni del chirurgo e la mancanza di linee guida condivise contribuiscono a determinare la
                                                                                                     article can be used by giving appropriate credit and mentio-
vasta eterogeneità osservata nella gestione del VS nel nostro Paese.                                 ning the license, but only for non-commercial purposes and
PAROLE CHIAVE: schwannoma vestibolare, neurinoma dell’acustico, microchirurgia,                      only in the original version. For further information: https://
                                                                                                     creativecommons.org/licenses/by-nc-nd/4.0/deed.en
radioterapia stereotassica, chirurgia del basicranio



                                                                                                                                                             185
N. Quaranta et al.




Introduction                                                    The 35-item, multiple-choice survey was divided into three
                                                                sections: i) general section, investigating years of training,
Vestibular schwannoma (VS) is a benign tumour arising
                                                                years of experience and volume/year of patients managed
from Schwann cells of the VIII cranial nerve and account
                                                                and treated; ii) section on overall practice patterns; and
for 5% to 9% of all brain neoplasms 1. The first evidence in
                                                                iii) section on management options. The full questionnaire
the literature dates to 1777 2. About 90% of these tumours
                                                                is reported in Appendix (https://www.actaitalica.it/article/
are unilateral and sporadic. They can also occur bilaterally,
                                                                view/1107/550).
generally when associated with genetic conditions such as
neurofibromatosis type 2 3. By exerting a compression on
                                                                Statistical analysis
the VIII cranial nerve, VS leads to progressive unilateral
                                                                Categorical variables were presented as frequencies with
sensorineural hearing loss (SNHL) and tinnitus in more
                                                                percentages; data were analysed per item, so the denomi-
than 90% of patients, while vestibular symptoms are pre-
                                                                nator varied per question due to missing data; comparisons
sent in ≤ 20%. Sudden SNHL may also be the first clinical
                                                                between variables were assessed using Chi-square or Fis-
presentation in up to 22% of cases 4.
                                                                cher’s exact tests, as appropriate. All tests were two-tailed
Over the past 40 years, the incidence rate of VS has stead-
                                                                and statistical significance was determined by a p value
ily increased from approximately 3 cases/million/year to
34 cases/million/year 5. This steep rise was probably due to    < 0.05. Data were analysed using the SPSS 20 software
VS early diagnosis with high-resolution contrast-enhanced       (SPSS, IBM Company, Armonk, USA) and GraphPad
MRI in patients with unilateral or asymmetric audiological      Prism version 7.00 for Windows, (GraphPad Software, La
symptoms, together with incidental findings from imaging        Jolla California USA, www.graphpad.com).
performed for unrelated complaints 6.
Although several cornerstones of diagnosis and therapy are      Results
recognised and shared between different centres, there are
                                                                Demographics, experience and setting
still controversies mostly related to the characteristics of
                                                                Sixty-six subjects responded to the survey, nine women
tumours and patients, as well as institutional preferences.
                                                                (13.8%) and 58 men (86.2%), mostly within the 50-59
A major role is probably played by the level of global ex-
                                                                year group of age (27.3%). Among them, 37 participants
pertise and the presence of a team. Daveau et al. 7 reported
                                                                (56.0%), 2 females (5.4%) and 35 males (94.6%), con-
that, depending on the specialist to whom the patient is
                                                                firmed their active involvement in the management of VS,
first addressed to, the treatment varies significantly, rang-
                                                                so that their responses were taken into consideration for
ing from observation to surgery and radiation therapy. The
                                                                further analysis. Among the study group involving 25 oto-
management of VS is thus strongly influenced by some
                                                                laryngologists (67.6%) and 12 (32.4%) neurosurgeons, 30
non-objective parameters, which play a relevant role in the
                                                                (81.1%) confirmed their specific training in neurotology/
choice of first treatment.
                                                                lateral skull base surgery, as shown in Figure 1A. Age dis-
The aim of the present study was to investigate the cur-
                                                                tribution and years of experience of the participants are re-
rent practice patterns of VS in Italy through an anonymous
questionnaire addressed to otolaryngologists and neurosur-      ported in Figures 1B and 1C.
geons.                                                          Most respondents, 22 (59.5%), claimed to work at a univer-
                                                                sity hospital, 12 (32.4%) at hospital without academic affil-
                                                                iation and three (8.1%) in private practice. With regards to
Materials and methods                                           the volume of cases evaluated by respondents, 17 (46.0%)
Study design and survey characteristics                         managed ≤ 25 cases/year, while 20 (54.0%) > 25 cases/
A web-based, anonymous survey was administered to the           year (5, 13.5% between 25 and 50; 10, 27.0% between 51
members of the Italian Society of Otolaryngology, Head          and 100; 5, 13.5% > 100 cases/year). There was a signifi-
and Neck Surgery (SIO) and the Italian Society of Neuro-        cant association between the number of tumours evaluated
surgery (SINCH) using the Google Drive platform. The sur-       per year and type of practice setting. Higher volumes of
vey was conceived in Italian, modifying that administered       cases (> 25 cases/year) were managed at academic settings
by the North American Skull Base Society (NASBS) 8, with        in 72.7% of cases while lower volumes (≤ 25 cases/year)
permission. The survey was distributed between Decem-           were mostly treated at hospitals without academic affilia-
ber 2018 and December 2019; after voluntarily agreeing          tion or in private practice in 73.3% of cases (p = 0.021). No
to participate, surgeons indicated their active involvement     associations were found between type of practice setting
into otoneurological/lateral skull base procedures and their    and years of experience (p = 0.279) or multidisciplinary
surgical specialisation.                                        approach (p = 0.317).



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Figure 1. Characteristics of survey participants. (A) Specialisation. (B) Age distribution defined in years. (C) Years of experience in VS care.


Management strategies                                                                prefer observation as first option, 4 (10.8%) recommend-
Eighteen respondents (50.0%) claimed to discuss patients                             ed microsurgical up-front treatment and three (8.1%) ra-
diagnosed with VS in multidisciplinary meetings. Twenty-                             diotherapy. Considering tumour observation, the 5-year
three (62.2%) claimed to surgically treat VS in teams where                          growth probability for intracanalicular VS and for small,
otolaryngologists and neurosurgeons are involved, and 14                             extrameatal VS (≤ 1.5) cm was considered < 25% by 27
(37.8%) performed surgical interventions on their own.                               (75.0%) and 16 (45.7%) participants, respectively. Most
                                                                                     respondents (28, 75.6%) believed that the best chance of
a. Intracanalicular VS and tumours ≤ 1.5 cm                                          retaining serviceable hearing at 10-year follow-up, is given
in the cerebello-pontine angle                                                       by conservative approach.
In case of small VS, 30 respondents (81.1%) declared to                              In case of surgery, 30 participants (83.4%) declared to



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N. Quaranta et al.




consider hearing preservation surgery (HPS) as a feasible                        surgical corridors independently. When stratified according
strategy, while six (16.6%) do not perform this surgical                         to specialisation of respondents, the TL approach was pre-
option, regardless of hearing status. Given favourable tu-                       ferred by otolaryngologists than neurosurgeons (18, 72.0%
mour characteristics and contralateral normal hearing, pure                      vs 1, 8.3%, p < 0.001). On the contrary, the RS corridor
tone average (PTA) ≤ 30dB and word recognition score                             was more frequently used by neurosurgeons (8, 66.7% vs
(WRS) ≥ 70% are considered neccessary to attempt HPS                             3, 12.0%, p < 0.001).
by 19 respondents (51.4%), while 5 (13.5%) believed that                         For large VS (> 3 cm), most respondents would perform
HPS should be tried with any detectable hearing. Among                           a single stage surgical resection (97.3%), either via TL
different factors affecting HPS outcomes, tumour size and                        (51.4%) or RS (43.2%) corridors. There was a significant
preoperative hearing were considered to be the strongest                         difference between otolaryngologists and neurosurgeons
predictors of on hearing outcomes by 28 (75.6%) and 19                           concerning the surgical approach for large VS resections.
(51.3%) respondents, respectively (Fig. 2). Tumour origin                        The former claimed to prefer the TL approach in 68.0%
(from the superior or inferior vestibular nerve), presence                       of cases, while the latter a RS approach in 75.0% of cases
of cerebrospinal fluid (CSF) fundal cup, patient’s age and                       (p = 0.012).
internal auditory canal enlargement were considered of av-                       Twenty-eight surgeons (75.6%) would try to achieve a to-
erage importance. Overall, the preferred approach for HPS                        tal resection of large VS, unless the tumour is tenaciously
was the retrosigmoid (RS) in the 61.2% of cases, for both                        adherent to the facial nerve. Six (16.2%) would perform
otolaryngologists and neurosurgeons (60.0% and 58.1%                             a subtotal resection to reach adequate tumour volume for
respectively). More than three-fourths of respondents                            subsequent stereotactic radiosurgery/stereotactic radiation
(77.8%) claimed to perform both the RS and middle crani-                         therapy (SRS/SRT), and only three (8.1%) would perform
al fossa approaches, depending on tumour characteristics.                        a total resection, even if it could place facial nerve function
The chance of preserving residual hearing after HPS was                          at risk. Only six (16.2%) respondents claimed to perform
estimated to be < 40% by 25 respondents (67.5%).                                 sub-total VS resections in large VS very frequently (more
                                                                                 than 50% of cases). Interestingly, when stratified accord-
b. Tumours > 1.5 cm in the cerebello-pontine angle                               ing to the surgical specialisation, neurosurgeons declared
In the case of tumours > 1.5 cm in the cerebello-pontine an-                     to perform subtotal resections more frequently than otolar-
gle or when HPS is not the target, 19 participants (51.4%)                       yngologists would (p < 0.001).
preferred the translabyrinthine (TL) approach, 11 (29.7%)                        When asked about intraoperative parameters that could
the RS approach and seven (18.9%) claimed to use both                            threaten facial nerve function, otolaryngologists consid-




Figure 2. Ranking of predictive factors for hearing preservation weighted by survey participants according to the perceived impact on successful hearing pres-
ervation surgery (1 = strongest predictor, 6 = weakest predictor). The average rating per item is reported between brackets.



188
                                                                                                  Current management of VS in Italy




ered tumour extension and grade of adhesion at the nerve/       VS management, 67.6% were otolaryngologists and 32.4%
tumour interface the most reliable (18, 75.0% vs 6, 25%,        neurosurgeons evaluating in 54.0% of cases > 25 VS pa-
p = 0.044), while neurosurgeons more frequently relied          tients/year. In 2006, Goodden et al. 10 investigated on the
on electrophysiological measures (6, 66.7% vs 3, 33.3%,         adherence to guidelines for diagnosis and treatment of VS
p < 0.001). Residual tumours were preferably observed and       in the United Kingdom and Ireland, reporting that 73.0%
submitted to SRS/SRT or observed and surgically treated         of neurosurgeons evaluate patients with otolaryngolo-
only after documented growth by 26 (72.2%) and seven            gists. Similarly, Saeed et al. 11 obtained comparable results
(19.5%) respondents, respectively. Early SRS/SRT (within        among otolaryngologists. In the present study, with regards
6 months from surgery) for residual VS was advocated by         to the initial assessment of VS patients, respondents were
three (8.3%).                                                   equally distributed between those who evaluate patients
                                                                alone (50.0%) and those who collaborate in a multidisci-
Symptom control and complications                               plinary team (50.0%). Interestingly, considering the multi-
Some questions regarded the surgical effects on symptom         disciplinary collaboration during surgery, 62.2% of otolar-
control. Most surgeons believe that VS surgical removal         yngologists and neurosurgeons claimed to work together.
has no or unpredictable effects on tinnitus (12, 32.4%, and     Although with higher rates of a multidisciplinary approach
20, 54.1%, respectively), while only four (10.8%) believe       to the VS patient, the survey conducted among NASBS
that surgical treatment would improve preoperative tinni-       members 8 reflected a similar increase of percentages
tus. In case of pre-operative dizziness, 28 (75.7%) respond-    in multidisciplinary collaboration during the diagnostic
ents suggested that surgery would lead to reduction/resolu-     (63.0%) and surgical phases (86.0%) of VS management.
tion of symptoms.
Dealing with surgical complications, the RS approach was        Observation
perceived to carry the highest risk of postoperative CSF        The spread of MRI has radically changed the diagnosis
leak (19 respondents, 51.4%) by both otolaryngologists          and treatment of VS, which today is based at first on ob-
and neurosurgeons (11, 44.0% vs 8, 66.4%). Interestingly,       servation 12. Both in Italy and USA 8 the most widespread
26 (70.3%) respondents did not avoid the RS approach de-        strategy for the treatment of small and medium sized VS is
spite the risk of post-operative headache.                      initial observation until tumour growth becomes evident.
                                                                This policy seems to be the best choice for both otolaryn-
Radiation treatment                                             gologists and neurosurgeons. In fact, the chance of growth
Thirty-one (83.7%) respondents recommend SRS/SRT in             is considered low after 5 years of observation, as shown by
less than 10 cases/year and most participants believe that      both the Italian and NASBS surveys 8. In this regard, Paldor
radiation treatment is not indicated as a primary option for    et al. 13 conducted a comprehensive review of the literature
tumours measuring > 2 cm (21.6%), > 2.5 cm (35.2%), and         considering 37 studies on > 4000 patients and reported that
> 3 cm (29.7%). Malignant transformation of VS after SRS/       only 50% of tumours demonstrated a radiologically docu-
SRT is generally considered to be extremely rare by most        mented growth after 5 years.
respondents (29, 78.4%). The questionnaire was, however,
not administered to radiation therapists.                       Surgery
                                                                The best surgical approach to treat VS, when hearing pres-
                                                                ervation is not the goal, is still a matter of debate among
Discussion                                                      lateral skull base surgeons, and is reflected in the present
Otolaryngologists and neurosurgeons directly involved in        study. A systematic literature review by Hadjipanayis et
the treatment of VS are faced with a wide range of differ-      al. 14 stated that there is insufficient evidence to support the
ent management possibilities, ranging from observation to       superiority of either RS or the TL approach for complete
active treatments like surgical tumour removal or radiosur-     VS resection and facial nerve preservation, when service-
gical irradiation 9. In the absence of international accepted   able hearing is not present.
guidelines in this field, and lacking adequate evidence to      In case of small to medium sized tumours, in the NASBS
guide VS management, the possible variability of practice       study 8 the TL approach was preferred, while in Italy a sig-
mainly reflects institutional and/or surgeon’s experience       nificant divergence between otolaryngologists and neuro-
biases. In the present study, the current treatment strate-     surgeons came to notice. In fact, while the former preferred
gies for VS in Italy are reported after a nationwide survey     the TL approach (72.0%), most neurosurgeons claimed to
administration among the SIO and SINCH members. Thir-           use the RS approach (66.7%). For large VSs (> 3 cm), most
ty-seven respondents confirmed their active involvement in      North American surgeons claimed to prefer the RS ap-



                                                                                                                              189
N. Quaranta et al.




proach (52.6%) 8, which is confirmed in Italy only among          middle cranial fossa approach (43.9%), Italians are more
neurosurgeons (75.0%), as otolaryngologists preferred the         prone to use the RS corridor for HPS (61.2%). More than
TL approach (68.0%).                                              half of respondents, (54.1%) considered hearing class A ac-
Facial nerve injury is one of the most frequent complica-         cording to the American Academy of Otolaryngology-Head
tions of VS surgery, particularly when the tumour reaches         and Neck Surgery (AAO-HNS) classification the main selec-
considerable size 15. Similar to what was reported in the         tion criterium for HPS, while most North American surgeons
NASBS study 8, our survey highlighted that most surgeons          (63.2%) considered more permissive preoperative hearing
(75.6%) try to achieve total resection of the tumour mass         intervals as AAO-HNS hearing classes A and B (PTA ≤ 50
unless it is tenaciously adherent to the facial nerve. Of note,   dB and SDS ≥ 50%) to perform HPS 8. There was agreement
most neurosurgeons claimed to perform subtotal resections         in considering both tumour size and pre-operative hearing
and to rely on electrophysiological measures to demonsrate        levels to be the most important factors influencing HPS out-
facial nerve integrity significantly more frequently than         comes, as resulting from the Italian and American surveys 8.
otolaryngologists, who were more prone to total resections        The recent literature demonstrated that besides the above-
and to rely on intraoperative assessment of tumour exten-         mentioned predictors of hearing outcomes after surgical VS
sion and adhesion at the nerve/tumour interface.                  removal, the presence of a fundal cap at the fundus of the
Considering the management of residual tumour after sub-          internal auditory canal must also be considered relevant 20.
total resections, most of the respondents (70.2%) would           Furthermore, Zanoletti et al. 21 investigated the predictors
adopt an observation policy followed by SRS/SRT only af-          of postoperative hearing in HPS performed through a mi-
ter documented growth. This is in accordance with Taha et         croscopic RS approach combined with a retrolabyrinthine
al. 16 reporting that, in case of important adherence with the    meatotomy. In the attempt to better define the HPS inclusion
facial nerve, a near-total tumour resection with eventual         criteria for achieving best hearing outcomes, cutoff levels for
subsequent radiation therapy would be the best strategy to        tumour size and preoperative hearing were calculated.
ensure the integrity of the nerve.
Considering symptom control, most respondents held that           Complications
surgery has an unpredictable effect on tinnitus. Notewor-         CFS leak is one of the most frequent complications of VS
thy, Wang et al. 17 showed that microsurgical VS resection        surgery, after VII cranial nerve palsy 22. While in North
led to Tinnitus Handicap Index reduction in up to 77% of          America 8 TL surgery was considered the approach with a
cases. Most surgeons in Italy and in North America consid-        higher risk of postoperative CSF leak (57.9% of respond-
ered that VS surgical removal led to a reduction or even to       ents), in Italy both otolaryngologists and neurosurgeons
the resolution of preoperative dizziness. Similarly, micro-       considered the RS approach riskier than the TL (51.4%).
surgical tumour removal and trigeminal nerve decompres-           A systematic review of complications conducted in 2012
sion is considered the preferred treatment in cases with VS       found the same conclusions, demonstrating that the RS ap-
and associated trigeminal neuralgia 18.                           proach was significantly associated with higher risk of CSF
                                                                  leak than RS and middle cranial fossa approach 22.
Hearing preservation surgery                                      Post-operative headache is commonly observed after the
Both in Italy and in North America 8 in case of small tu-         RS approach 22,23, although 70.3% of Italian and 71.6% of
mours most of the respondents agreed that the high-               North American surgeons 8 did not consider this event an
est chance to preserve hearing is observation. Reznitsky          absolute contraindication for the approach.
and Cayé-Thomasen 19 showed in a systematic review of
the literature that the chance of preserving good hearing         Radiation
(PTA < 30 dB and WRS > 70%) after 5 years of observa-             Radiation treatment of VS is rarely proposed in Italy by
tion is 50%. In case of HPS, according to the “Congress of        either otolaryngologists or neurosurgeons; 83.7% of the in-
Neurological Surgeons” 20, the overall probability of main-       terviewees recommend SRS/SRT in less than 10 cases/year.
taining serviceable hearing following microsurgical resec-        Regarding the cut-off size of tumours to address for SRS/
tion of small to medium-sized sporadic VS is moderately           SRT, there was a substantial orientation among respond-
low (> 25%-50%), while in case of a good pre-operative            ents in both Italy and in North America to consider tumours
hearing level (PTA < 30 dB and WRS > 70%) the overall             between 2 and 3 cm as candidates for radiation treatment,
probability is moderately high (> 50%-75%) after surgery          excluding those with larger (for which the first option re-
and progressively decreases over time.                            mains surgical) and smaller dimensions (for which the best
HPS is performed by 83.4% of the Italian survey respond-          strategy is observation). A study conducted by Golfinos et
ents. While the North American surgeons 8 preferred the           al. 24 showed that SRS for tumours ≤ 2.8 cm was associated



190
                                                                                                                       Current management of VS in Italy




with low morbidity and good response to treatment. One                       10
                                                                                  Goodden JR, Tranter R, Hardwidge C. Setting the standard - UK
                                                                                  neurosurgical acoustic neuroma practice. Ann R Coll Surg Engl
of the drawbacks of radiation therapy, i.e the possibility of
                                                                                  2006;88:486-489. https://doi.org/10.1308/003588406X114893
malignant degeneration after treatment 25, is considered in                  11
                                                                                  Saeed SR, Suryanarayanan R, Dezso A, et al. Vestibular schwannoma
both the NASBS and the present studies as an infrequent                           management: current practice amongst UK otolaryngologists - time
event.                                                                            for a national prospective audit. Ann R Coll Surg Engl 2006;88:490-
                                                                                  495. https://doi.org/10.1308/003588406X114901
                                                                             12
                                                                                  Yao L, Alahmari M, Temel Y, et al. Therapy of sporadic and NF2-
Conclusions                                                                       related vestibular schwannoma. Cancers (Basel) 2020;12:835. https://
                                                                                  doi.org/10.3390/cancers12040835
The present study documents current practice patterns of VS                  13
                                                                                  Paldor I, Chen AS, Kaye AH. Growth rate of vestibular schwan-
care in Italy and provides the first overview on VS manage-                       noma. J Clin Neurosci 2016;32:1-8. https://doi.org/10.1016/j.
ment of the nationwide community of otoneurosurgical, neu-                        jocn.2016.05.003
rosurgical and skull base surgeons. Although adopted by most                 14
                                                                                  Hadjipanayis CG, Carlson ML, Link MJ, et al. Congress of Neurolog-
centres for surgical VS treatment, a multidisciplinary model                      ical Surgeons Systematic Review and Evidence-Based Guidelines on
                                                                                  surgical resection for the treatment of patients with vestibular schwan-
of care including otolaryngologists and neurosurgeons needs                       nomas. Neurosurgery 2018;82:E40-E43. https://doi.org/10.1093/neu-
to be encouraged, especially regarding the initial VS assess-                     ros/nyx512
ment and decision-making. Tumour observation and radio-                      15
                                                                                  Grinblat G, Dandinarasaiah M, Braverman I, et al. Large and giant
logical growth monitoring is advocated by most interviewees                       vestibular schwannomas: overall outcomes and the factors influenc-
                                                                                  ing facial nerve function. Neurosurg Rev 2020 Aug 29 (Epub ahead of
in case of small VS. However, there is wide heterogeneity                         print). https://doi.org/10.1007/s10143-020-01380-6
in experience and practices for VS care, mostly influenced                   16
                                                                                  Taha I, Hyvärinen A, Ranta A, et al. Facial nerve function and hearing
by the surgeon’s different specialties. These results reflect a                   after microsurgical removal of sporadic vestibular schwannomas in
general lack of scientific evidence, and national guidelines                      a population-based cohort. Acta Neurochir (Wien) 2020;162:43-54.
                                                                                  https://doi.org/10.1007/s00701-019-04055-4
will foster future research in this field.                                   17
                                                                                  Wang JJ, Feng YM, Wang H, et al. Changes in tinnitus after vestibular
                                                                                  schwannoma surgery. Sci Rep 2019;9:1743. https://doi.org/10.1038/
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