Добавил:
Sekretar
kiopkiopkiop18@yandex.ru
t.me/Prokururor I Вовсе не секретарь, но почту проверяю
Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз:
Предмет:
Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_4372_Библиотеки_им_академика_М_И_Перельмана
.pdf
34 Transoral Resection forOropharyngeal Neoplasms
https://t.me/med1917
Fig. 34.23 Distending oropharyngoscope
cause considerable pain post-operatively. The F-K retractor
has the added advantage of cheek retractors, improving the
exposure, and a suction port allowing easier smoke suction.
Another option for smoke suction is to place a transnasal
Jaques catheter with the tip sitting just behind the soft palate.
When accessing the tongue base, it may be necessary to use
a distending oropharyngoscope (Fig.34.23), ideally with an
inbuilt smoke extraction channel.
The philosophy and technique behind removing oropharyngeal tumours with the laser was dened and developed by
Steiner and Ambrosch. Initially controversial, but necessary
due to space constraints, they described a trans-tumoral
resection approach. Despite initial criticism, subsequent data
conrmed that this approach does not confer an oncological
disadvantage; rather, a technical advantage is gained as there
is greater appreciation of the 3D orientation of the tumour
which facilitates complete tumour resection with minimal
resection of adjacent normal tissue. Specically, the
technique involves dividing the tumour in at least two
planned pieces in order to accurately visualise the depth,
thus allowing for complete resection whilst sparing adjacent
healthy tissue. Larger tumours can be removed in multiple
segments using the same principles (Fig.34.24). The ethos
behind this is to remove only the involved tissue with the
narrowest normal tissue margin, thus leaving more healthy
tissue in an attempt to reduce side effects, length of hospital
stay, and post-operative pain.
The initial cut is made through the centre of the tumour
(Fig.34.25 and 34.26). The surgeon becomes quickly familiar with the differences in cutting characteristics of tumour
and healthy tissue. Tumour causes a lot of charring and it is
not unusual to need to increase the laser power. Having transected the tumour, the deep healthy tissue will suddenly
spring open, and this can be clearly seen under the microscope. It is important to extend the incision a couple of mil-
341
Fig. 34.24 Diagram to show tumour (blue) highlighting the importance of transecting the tumour to get the correct depth (dashed line) as,
otherwise, there is danger of incomplete excision (solid line)
Fig. 34.25 Intra-operative photo of right tonsil tumour showing initial
incision (arrow)
limetres more to ensure an adequate, albeit minimal,
resection margin. The use of insulated grasping monopolar
forceps can be useful not only to dissect out tissue planes but
also to locate and diathermy vessels. These can then be dealt
with using either suction monopolar, insulated forceps or
ligaclips.
Once the depth of the tumour has been assessed, it is
important to make adequate superior, lateral, and medial
mucosal cuts (Fig.34.27 and 34.28).
When removing the superior section of the tumour, it is
important to maintain the correct orientation of the tumour
and following removal, to pin it to a piece of cork. The
mucosa will tend to shrink by up to 30% during histopathological processing, so it can be helpful to pin the very edge of
the specimen and stretch it out in an attempt to reduce this.
342
https://t.me/med1917
M. Fernández et al.
Fig. 34.26 Intra-operative photograph showing incision completely
through the tumour (normal muscle can be seen underneath)
Fig. 34.27 Intra-operative photograph showing where the superior
mucosal cut would start (dashed line)
The tumour will often be classied as having involved or
close margins at the deepest point of transection, due to the
normal tissue shrinkage during pathological processing. It is
important, therefore, to communicate clearly with both
pathologist and oncologist about the procedure and why this
appears to be so (Fig.34.29). Coloured needles are used to
identify the lateral and medial aspect of the tumour and it can
be useful to draw out the specimen with precise labels, thus
allowing accurate interpretation by the pathologist. In light
of this lack of standardisation, clear and regular objective
communication with the pathologist and oncologists is
essential to avoid misinterpretation and subsequent overtreatment (Fig.34.30).
Fig. 34.28 Intra-operative photograph showing where the medial
mucosal would be placed (dashed line)
Fig. 34.29 Diagram showing how a specimen would be pinned out (on
cork) highlighting how the muscle (red) can shrink back from the deep
edge of the tumour (blue) giving a false impression of an involved margin (yellow circle)
Fig. 34.30 Specimen pinned out on cork with superior (blue needle)
and lateral (green needle) edges marked out. A superior mucosal margin
can be seen pinned out above the specimen
34 Transoral Resection forOropharyngeal Neoplasms
https://t.me/med1917
343
Marginal biopsies are taken and this again is reassuring
for all parties that excision is complete. For tonsil tumours,
we would routinely take superior lateral mucosal, superior
mucosal, superior medial mucosal, and superior deep marginal biopsies and then repeat this for the inferior section.
The superior, medial, and lateral margin can be taken in continuity and then pinned out above the specimen adding clarity for the pathologist. In the tongue base, representative
lateral, medial, and deep marginal biopsies are typically
harvested.
In our practice, we typically perform oropharyngeal
resection in conjunction with a neck dissection. Ligation of
the external carotid artery (ECA) above the level of the superior thyroid artery in order to reduce the immediate
post- operative risk of bleeding is routine in our practice, in
an attempt to reduce major post-operative haemorrhage from
the primary resection site. We have recently shown from our
own data (unpublished) that ECA ligation results in a postoperative bleed rate of 5.3% compared to 10.2% in the nonligated patients. Since ligation of the ECA became standard
practice in our unit, we have had no major primary site
haemorrhages.
TLM is more challenging in the tongue base, compared to
the tonsil, so it is important to achieve as much exposure as
possible. Unless the tumour is very small, it is likely that
only a supercial region of part of the tumour is initially visible through the endoscope. Accordingly, it can be easy to
get disorientated as no anatomical landmarks are visible.
This highlights how important it is to perform a thorough
assessment on the day, prior to resection, so that you have a
mental picture of where the tumour is and the resection that
is needed. It is also harder to differentiate tumour from
healthy adjacent lymphoid tissue, thus complicating matters
further: Some centres advocate the use of intra-operative frozen sections as a matter of routine, for this very reason.
Performing perpendicular cuts through the tumour to segment it and to gain an appreciation of the depth of invasion
can aid resection, as without this, the resected tissue can
become cumbersome and depth of invasion difcult to gauge.
After the initial vertical transection of the tumour, the scope
may need to be advanced or a different scope utilised in order
to achieve continued exposure to facilitate adequate resection
of the tumour. One must be mindful of the direction of the
tumour relative to the natural contours of the base of tongue
and vallecula and adjust the angle of resection to avoid
unnecessary dissection deep into the intrinsic tongue musculature or scalloping into the deep surface of the tumour.
In larger tongue base resections, one must be mindful of
the lingual artery as bleeding intra-operatively can be brisk
and difcult to control. To pre-empt any problems, it is sensible to have a second suction on stand-by mode as the small
monopolar suction is often inadequate to maintain a bloodless eld whilst haemostasis is achieved. If encountered,
then our preference is to apply three ligaclips to the vessel as
well as ligating the lingual artery, as part of the ECA ligation,
in the neck. The hypoglossal nerve runs deeper and more
lateral to the lingual artery, so it should be protected if the
lingual artery is preserved.
34.3.3 Complications andOutcomes
In our unit, median length of hospital stay is 4days and 97%
of patients are swallowing normally on discharge. If, as is
usually the case, a neck dissection is performed concurrently,
then a suction drain remains in situ until the output is less
than 20mL in the preceding 6h.
The main complications that patients are counselled about
pre-operatively include bleeding and post-operative (usually
transient) deterioration in swallowing. The aim of TLM, as
part of deintensication treatment strategies, is to reduce
both long- and short-term treatment-related adverse effects
whilst maintaining comparable or even improved survival
outcomes compared with alternative standard of care treatments. We have established (unpublished data) that 97% of
our patients are discharged home swallowing adequately to
the extent that supplemental feeding is not required, even in
the short term. In the long term, our management strategy of
TLM and selective neck dissection followed by postoperative radiotherapy in the majority of cases (73%) results
in a gastrostomy dependency rate at 1 year of 2.3%.
Moreover, the 5-year overall survival (OS), disease-free survival (DFS), and disease-specic survival (DSS) are, respectively, 74.9%, 73.7%, and 86.2% and 5-year locoregional
control (LRC) was achieved in 87.1% of cases.
References
1. Høxbroe Michaelsen S, Grønhøj C, Høxbroe Michaelsen J, Friborg
J, von Buchwald C.Quality of life in survivors of oropharyngeal
cancer: a systematic review and meta-analysis of 1366 patients. Eur
J Cancer. 2017;78:91–102.
2. Ryzek DF, Mantsopoulos K, Künzel J, Grundtner P, Zenk J, Iro H,
Psychogios G.Early stage oropharyngeal carcinomas: comparing
quality of life for different treatment modalities. Biomed Res Int.
2014;2014:421964.
3. Orlandi E, Licitra L. Personalized medicine and the contradictions and limits of rst-generation deescalation trials in patients
with human papillomavirus-positive oropharyngeal cancer. JAMA
Otolaryngol Head Neck Surg. 2018;144:99–100.
4. Strong MS, Jako GJ, Polanyi T, Wallace RA. Laser surgery in the
aerodigestive tract. Am J Surg. 1973;126:529–33.
5. Hinni ML, Nagel T, Howard B.Oropharyngeal cancer treatment:
the role of transoral surgery. Curr Opin Otolaryngol Head Neck
Surg. 2015;23:132–8.
6. Patel SH, Hinni ML, Hayden RE, Wong WW, Dueck AC, Zarka
MA, et al. Transoral laser microsurgery followed by radiation
therapy for oropharyngeal tumors: the Mayo Clinic Arizona experience. Head Neck. 2014;36:220–5.
344
https://t.me/med1917
M. Fernández et al.
7. O’Malley BW Jr, Weinstein GS, Snyder W, Hockstein
NG. Transoral robotic surgery (TORS) for base of tongue neoplasms. Laryngoscope. 2006;116:1465–72.
8. Tomifuji M, Araki K, Yamashita T, Shiotani A.Transoral videolaryngoscopic surgery for oropharyngeal, hypopharyngeal, and supraglottic cancer. Eur Arch Otorhinolaryngol. 2014;271:589–97.
9. Fernández-Fernández MM, Montes-Jovellar L, Parente Arias PL,
Ortega Del Alamo P. TransOral endoscopic UltraSonic Surgery
(TOUSS): a preliminary report of a novel robotless alternative to
TORS.Eur Arch Otorhinolaryngol. 2015;272:3785–91.
10. Lim CM, Mehta V, Chai R, Pinheiro CN, Rath T, Snyderman C,
Duvvuri U. Transoral anatomy of the tonsillar fossa and lateral
pharyngeal wall: anatomic dissection with radiographic and clinical correlation. Laryngoscope. 2013;123:3021–5.
11. Howard J, Masterson L, Dwivedi RC, Riffat F, Benson R, Jefferies
S, etal. Minimally invasive surgery versus radiotherapy/chemoradiotherapy for small-volume primary oropharyngeal carcinoma.
Cochrane Database Syst Rev. 2016;12:CD010963.
Robotic Surgery
https://t.me/med1917
SomiahSiddiq, F.ChristopherHolsinger, andVinidhPaleri
35
35.1 Introduction
Transoral robotic surgery (TORS) has revolutionised endoscopic approaches to head and neck surgery, replacing previous signicant morbid transcervical and transfacial surgical
access approaches. By harnessing the natural opening of the
mouth, TORS facilitates natural orice transluminal endoscopic surgery (NOTES). TORS offers several technological
advances to standard transoral approaches, including
improved magnied three-dimensional visualisation allowing angled sight lines, tremor-free wristed instrumentation
with 7° of freedom, a rapid learning curve in comparison to
transoral laser techniques and the ability to perform an en
bloc compartmental resection and thereby more condent
margin assessment.
This chapter will provide an overview of the rationale and
evidence base supporting TORS for primary cancers of the
oropharynx and the emerging role of TORS in the investigation of the carcinoma of unknown primary (CUP). A detailed
step-by-step operative technique is described for lateral oropharyngectomy, tongue base mucosectomy (TBM) and
tongue base hemiglossectomy.
S. Siddiq (*)
Division of Head and Neck Surgery, Department of
Otolaryngology, University Hospitals Birmingham NHS
Foundation Trust, Birmingham, UK
e-mail: somiah.siddiq@nhs.net
F. C. Holsinger
Division of Head and Neck Surgery, Department of
Otolaryngology, Stanford University, Palo Alto, CA, USA
e-mail: holsinger@stanford.edu
V. Paleri
Division of Head and Neck Surgery, The Royal Marsden NHS
Foundation Trust & The Institute of Cancer Research, London, UK
e-mail: vinidh.paleri@rmh.nhs.uk
35.2 Indications
The da Vinci Surgical System was approved by the Food and
Drug Administration (FDA) in 2009 [1] for the management
of T1 and T2 malignancies of the oropharynx and larynx and
benign diseases. However, the reader should bear in mind
that there is emerging evidence supporting the roles of TORS
in advanced oropharyngeal cancer (T3 and T4) [2] and in the
setting of residual and recurrent disease [3] where open
approach salvage surgery is both technically challenging and
associated with high morbidity rates.
The majority of TORS defects are left to heal by secondary intention, providing the additional benets of a mucosalised, sensate healed wound.
35.2.1 Oropharynx
To obviate the signicant morbidity of traditional transcervical and transmandibular surgical approaches, with the associated risk of swallowing and speech dysfunction, organ
preservation strategies with (chemo)radiotherapy were
adopted [4]. But several studies eliciting patient priorities
have identied that survivors of oropharyngeal carcinoma
(OPC) after non-surgical treatment, rate dysphagia as the
most signicant functional impairment. In the pooled analysis of three Radiation Therapy Oncology Group (RTOG) trials [8], late grade 3–4 laryngopharyngeal toxicity was
reported in 35% of 101 survivors of OPC 5 years posttreatment. A combination of the rising incidence of human
papillomavirus (HPV)-related oropharynx cancer, presentation in a younger cohort of patients, concerns with late toxicities with (chemo) radiotherapy, and patient-reported
experiences [5–7] triggered the need to revisit the role of
primary surgery in this setting. Furthermore, HPV-related
oropharynx cancer often presents with small primary tumour
volume and is thus more amenable to minimal access surgical approaches.
© Springer Nature Switzerland AG 2024
R. Simo et al. (eds.), Atlas of Head and Neck Surgery, Springer Surgery Atlas Series,
https://doi.org/10.1007/978-3-031-36593-5_35
345
346
https://t.me/med1917
S. Siddiq et al.
Of the various subsites, the greatest experience and longest duration of follow-up has been in the setting of TORS
for OPC.
The rst case report of robotic surgery for oropharyngeal
cancer was published in 2005 [9]. Since then, a rich retrospective, prospective and phase II trial evidence base has
emerged supporting the role of TORS in this subsite. A multicentre study of 410 patients [10] treated by TORS at 11
centres worldwide, demonstrated 2-year loco- regional control of 92%, disease-specic survival of 95% and overall survival of 91%. The vast majority of patients (90%) were early
stage (84% T1–T2) oropharynx tumours.
A further meta-analysis [11] comparing TORS and
intensity- modulated radiotherapy (IMRT) in early oropharyngeal cancer reviewed 20 case series comparing 772
patients receiving primary surgery versus 1287 patients
receiving non-surgical treatments. Both modalities conferred
similar 2-year overall survival estimates: 84–98% for IMRT
versus 82–94% TORS.Differences were however evident in
the adverse event prole of each modality. In patients receiving IMRT, these included oesophageal stenosis (4.8%),
osteoradionecrosis (2.6%) and gastrostomy tubes (43%),
whilst those receiving TORS experienced haemorrhage
(2.4%), stula (2.5%) and gastrostomy tubes at the time of
surgery (1.4%) or during adjuvant treatment (30%).
Tracheostomy tubes were needed in 12% of patients at the
time of surgery, with the majority decannulated prior to discharge [11].
More recently, TORS with de-escalation of adjuvant
radiotherapy dose for intermediate risk p16+ oropharyngeal
cancer was studied within a phase II trial envelope (ECOGACRIN 3311); this demonstrated good oncological outcomes comparable to surgery and standard dose radiotherapy
(2-year progression-free survival 95.0% TORS and 50 Gy
versus 95.9% for TORS and 60Gy) [12].
Swallowing function in patients who undergo TORS for
primary cancer has been shown to recover by 6weeks [13].
Furthermore, a matched prospective cohort study [14] comparing functional swallowing outcomes in TORS versus primary chemoradiotherapy in advanced, predominantly
oropharynx cancers, demonstrated signicantly better MD
Anderson Dysphagia Inventory (MDADI) scores in the
TORS cohort at 6 and 12months, respectively, suggesting
improved long-term recovery in comparison to chemoradiotherapy (CRT). Furthermore, functional benets of TORS in
comparison to non-surgical approaches include: less overall
rates of feeding tube placement against published IMRT
datasets and reduced aspiration and avoidance of late toxicity effects of radiation-based organ preservation regimes
(late-radiation associated dysphagia [RAD] in 5- and 10-year
survivors) [15]. A recent phase II randomised controlled trial
[16] compared subjective (MDADI scores) functional outcomes of up-front CRT versus TORS and neck dissection
with adjuvant CRT as appropriate in the setting of T1 or T2,
N0-2 OPC.The study failed to detect a clinically meaningful
change using a ten-point difference in MDADI scores,
although yielding a statistical difference, which has no clinical anchor (MDADI total scores at 1year favouring radiotherapy 86·9, SD 11·4 versus 80·1, SD 13.0 p = 0.042).
Limitations of the study include appropriate case selection
(with the majority of patients with N2 disease resulting in
dual and triple modality therapy in the surgical arm), the use
of subjective rather than standardised objective functional
outcomes (such as videouoroscopy) and short-term follow up not accurately capturing the known late toxicity effects of
CRT.Many patients also received routine planned tracheostomy, which skewed functional outcomes results for patients
undergoing TORS.
Appropriate case selection in TORS is key to minimise
multi-modality therapy and is often dictated largely by the
stage of neck disease. The optimal goal of treatment in HPVrelated oropharynx cancer is single modality up-front surgical treatment alone or within the setting of a clinical trial to
facilitate the de-escalation of adjuvant therapies.
35.2.2 TORS fortheUnknown Primary
The most common site for carcinoma from an unknown primary (CUP) is the oropharynx, with the tonsil and tongue
base (TB) accounting for 90% of all identied CUP sites
[17]. The traditional approach of random biopsies of the
tongue base has a low probability of primary site detection,
ranging from 25 to 43%. This is partly due to the crypts
within the tongue base lymphoid tissue, large surface area of
the lingual tonsillar bearing area of the TB and the inconspicuous submucosal nature of the primary tumours in HPVpositive OPC, with the mean size often less than a centimetre
[18]. Although PET-CT can, compared to conventional
imaging, detect additional primary tumours in in 37–44%
[19, 20] of patients, it does not reliably detect sub-centimetre
[21, 22] tumours; additionally, PET-CT is associated with a
false-positive rate of up to 39% due to the physiologic uptake
in the lymphoid tissue of the Waldeyer’s ring, and histological corroboration is required to determine treatment
decisions.
Tongue base mucosectomy (TBM), rst described by
Mehta et al. [17], removes the entire lingual tonsils to the
depth of the muscular layer from the circumvallate papillae
to the vallecula and laterally to the glossopharyngeal sulcus.
This allows a full histological assessment to identify primary
tumours in this anatomical subsite.
A systematic review [23] incorporating 139 patents from
eight studies (six TORS and two TLM) in the setting of CUP
identied 59% of primary tumours in patients with no abnormal ndings on physical examination, examination under
35 Robotic Surgery
https://t.me/med1917
347
anaesthesia and imaging. Lingual tonsillectomy provided
incremental primary tumour detection in 72% of patients,
where no abnormal ndings had been detected with prior
comprehensive diagnostic assessment. In the UK experience
[24], the primary site was identied in the tongue base in
53% of a cohort of 32 patients with CUP (dened as negative
ndings on clinical examination, cross-sectional imaging,
PET-CT imaging, bilateral tonsillectomy, and biopsies of the
tongue base). Similar results are conrmed from the largest
systematic review and meta-analysis [25] to date on TBM, in
a pooled cohort of 556 patients from 21 studies. TBM identied the primary in 53% of cases, but if performed following
negative diagnostic investigations (conventional imaging,
PET-CT, examination under anaesthesia, and palatine tonsillectomy), the detection rate of the primary in the tongue base
increased to 78%.
Current guidance [26, 27] recommends TBM as part of
the surgical diagnostic pathway in the setting where FDG
PET-CT does not identify a possible primary site. An ongoing UK multicentre observational cohort (MOSES) study
[28] aims to establish if step serial sectioning compared to
conventional histopathological assessment improves the
identication of a primary in TBM specimens.
A bilateral TBM is recommended when one considers the
bilateral cervical drainage from the tongue base and is substantiated by a tumour detection rate of 1.85–12% on the
contralateral side [18, 24, 25].
Overall morbidity is low in the context of TBM, with
postoperative haemorrhage most commonly reported (5%)
[23, 25].
Preliminary data indicates that identication of the primary tumour in CUP is associated with improved overall,
cause-specic and disease-free survival [24, 29] with the
potential avoidance of wide-eld mucosal irradiation and
reduced treatment toxicity [30]. The associated morbidity of
wide-eld mucosal irradiation, although improved since the
introduction of IMRT, is still not insignicant, with oesophageal stricture rates of 5–54% [31, 32].
Furthermore, identication facilitates recruitment of a
group of patients who would otherwise have been denied the
opportunity to enter de-escalation trials such as PATHOS
[33], alleviates psychosocial patient/clinician burden in the
context of diagnostic uncertainty and denes a ‘true’ subset
of CUP patients for further research.
TORS-facilitated TBM is considered a diagnostic tool in
the setting of CUP. Current consensus guidelines to dene
appropriate algorithms and optimal extent of TORS TBM
[17] vary [26, 27]. The benet of simultaneous palatine tonsillectomy combined with TBM should be weighed against
the potential increased risk of postoperative morbidity and
late pharyngeal stenosis, the latter which may be exacerbated
with subsequent adjuvant CRT. Other considerations include
increased costs, delay in overall planned treatment and the
short-term impact on swallow. Ideally, all patients preparing
for TBM should undergo a comprehensive swallow assessment to ensure a patient-tailored approach to quantify potential risk to swallow function and ensure optimal patient
counselling and consent.
The role of TORS TBM as a potential therapeutic tool is
a topic of ongoing review and research. The margin that is
most likely to be positive in TBM is often the deep margin,
with 71% of positive margins found in the BOT and 29% in
the palatine tonsils [17]. Some authors [34] have advocated
taking a ‘sliver’ of the muscular layer on the ipsilateral
tongue base at the time of bilateral TBM, but this has to be
weighed against potential increased morbidity and bleeding
risk [17].
Compartmental re-resection approaches, which have been
shown to be highly effective in palatine tonsillectomy in
CUP in the close/positive margin scenario [35], may need to
be adopted to the tongue base. However, some might question the oncologic value of macroscopic surgical excision of
microscopic T1 tumour.
35.3 Preoperative Checklist,
Considerations andAnaesthesia
35.3.1 Patient Selection
Prior to the multidisciplinary team meeting, the surgeon
performing the TORS should ensure appropriate suitability
for TORS candidacy through a triple assessment of (1)
physical examination (including exible nasal endoscopy
in the clinic setting), (2) CT and MRI imaging review and
(3) formal examination under anaesthesia and panendoscopy. The latter will determine, rst, the feasibility of
access with the specic mouth retractor that will be used
during the robotic procedure and, second, tumour suitability for resection through direct visualisation and palpation
to assess depth, surface extension and underlying xation.
This step is always repeated at the beginning of the TORS
procedure to ensure a mental 3D-image of the en bloc
resection is visualised, especially as distortion often results
in base of tongue tumours due to compression by the tongue
blade once the patient’s mouth is open and the mouth
retractor is suspended.
In an attempt to determine the goals for potential contraindications, Weinstein and O’Malley, the original pioneers of
TORS, have eloquently summarised three considerations
[33]: (1) to minimise vascular complications, (2) to ensure
successful and reproducible functional outcomes and (3) to
maximise achievement of negative margins (and thereby crucially avoidance of adjuvant therapy). Broadly speaking,
contraindications for TORS can be divided into patient and
tumour factors (Table35.1) [36, 37].
348
https://t.me/med1917
Table 35.1 Patient and tumour factor considerations in TORS
Contraindications Tonsil Base of tongue
Tumour factors Vascular
Functional
Oncological
Patient factors • Medical conditions (coagulopathy, immunosuppression)
• Medialised/retropharyngeal carotid artery
• T4b disease involvement of carotid artery by primary
tumour or by a metastatic node
• Greater than 50% of posterior pharyngeal wall • Greater than 50% of tongue base
• T4b disease
• Fixation of tonsillar cancer
• Unresectable neck disease
• Cancer related trismus
• Distant metastases
• Anatomical constraints: non-cancer related trismus, narrow
mandibular transverse dimension, prominent incisor teeth,
macroglossia
• Cervical spine inexibility
• Tumour epicentre midline of tongue
base/vallecula-risk to bilateral lingual
arteries
musculature
• T4b disease
• Extension lateral to hyoid bone
involving lingual artery and
hypoglossal nerve
• Unresectable neck disease
• Distant metastases
S. Siddiq et al.
A functional swallow assessment by speech and language
pathologist/therapist is imperative both preoperatively and
postoperatively, including utilisation of standardised validated QoL questionnaires.
35.3.2 Management oftheNeck
In the setting of squamous cell cancers of the tonsil or tongue
base, the neck will need to be addressed with either a staging
(N0) or therapeutic (N+) neck dissection. Whether a selective neck dissection is conducted at the time of the TORS
resection (concurrent) or staged is dependent on several
factors.
A staged neck dissection, 7–10days prior to the TORS
resection, may be considered where there is a concern of
pharyngocutaneous stula formation in the setting of either
larger T2 tumours or the inclusion of level I as part of the
standard II–IV neck dissection [38–40]. This also potentially
provides additional advantages: it reduces the overall operative time and laryngopharyngeal swelling [39] and maximises usage of the robotic time in centres with time-limited
access to the da Vinci system. However, a staged neck dissection has to be balanced against the disadvantages of an
additional general anaesthetic, hospital stay and the potential
delay of adjuvant therapy [39].
If no relevant clinical contraindications exist, a neck dissection should be performed, ideally concurrently, preceding
the TORS resection. During the neck dissection, appropriate
branches of the external carotid are ligated to reduce the risk
and severity of postoperative haemorrhage following transoral surgery [41, 42]; facial artery for tumours of the tonsil,
lingual artery for tongue-base tumours, both for tumours that
arise in the glossopharyngeal sulcus or involve both sites.
Given the anatomical variability and for reasons of consistency, the authors advocate ligation of the facial and lingual
arteries at the minimum in all cases; efforts should be made
to identify and ligate the ascending pharyngeal if present.
35.3.3 Anaesthetic Considerations
Oral intubation with a small tube provides adequate access
for almost all tonsil and tongue base resections in the primary setting. Some surgeons, however, prefer contralateral
nasal intubation in order to provide more working space
within the oral cavity. In cases where a tracheostomy is
planned as part of the postoperative management, oral intubation followed by an up-front tracheostomy can be arranged.
Conventional endotracheal tubes will sufce for TORS, with
the smallest size that will allow for the ventilatory requirements, as this will maximise operating space. Owing to the
potential risk of airway re with the use of monopolar cautery, inspired FiO2 concentrations should be kept low with
the team procient in timely undocking of the robot to
address the patient airway in an emergency. Eye protection
in TORS procedures should utilise Opti-Gard eye protection
(adhesive-backed foam goggles with hard clear plastic
lenses) to protect the patient’s eyes from potential pressure
from the robotic arms or surgical instruments. The dentition
is protected with preformed vacuum dental guard/splints.
The advantage of the latter is they can be formed to a fewmillimetre thickness, maximizing exposure while simultaneously protecting the ventral tongue from trauma, as it is
compressed between the tongue blade and lower dentition.
To avoid lip injury from the instrument arms of the robot, a
transparent lip retractor can be used.
Prior to commencement of the TORS resection, clear
communication between the anaesthetic team and surgeons
is imperative to ensure the patient is fully immobilised with
appropriate pharmacological paralysis. Sudden jaw closure
against the robotic arms may occur and lead to devastating
P
Palatoglossal arch
yngeal
ular
35 Robotic Surgery
https://t.me/med1917
349
consequences. Once the robot is docked, the patient will not
be able to be moved or repositioned, and ease and speed of
access to the patient is restricted. Therefore, any monitoring
or protective devices should be placed beforehand and
secured meticulously, with extension lines where required.
Prophylactic antibiotics are given prior to the start of the
operation.
35.4 Surgical Technique withTips
TORS facilitates exposure and dissection of the transoral
surgical corridors to the parapharyngeal space (PFS), masticatory space and infratemporal fossa (Figs.35.1 and 35.2).
Fig. 35.1 Anatomy of the
oropharynx and base of
tongue demonstrating key
neurovascular and muscular
structures
alatopharyngeus muscle
Lingual nerve
Superior
pharyngeal
constrictor muscle
Palatoglossus muscle
The medial pterygoid muscle, considered the anatomic
watershed, divides the masticatory space and infra-temporal
fossa (superior lateral corridor) from the middle and lower
PFS (inferior medial corridor).
Following orotracheal intubation, appropriate eye protection and vacuum-formed splints are placed, particularly on
the lower dentition, to minimise trauma. A retraction suture
is placed in the midline of the anterior tip of the tongue to
allow appropriate exposure of operative eld and left attached
to a haemostat outside the patient’s mouth to ensure it is
removed at the end of the procedure. For tonsillar tumours,
the Boyle-Davis gag with appropriate suspension provides
adequate exposure. The patient cart of the da Vinci is then
docked on the left-hand side of the patient. The 0° or 30°
Lingual artery
Facial artery
External carotid artery
Ascending phar
artery
Ascending
palatine artery
Tonsillar branch
XII
IX
Palatopharyngeal arch
Fig. 35.2 Optimal exposure
obtained by manual
protrusion of tongue and
suture of ET tube to the
opposing retromolar trigone
with epiglottis clearly in view.
An incision is made through
the pterygomandibular raphe
(hatched line demonstrates
outline of en bloc TORS
resection) to enter the
parapharyngeal space
[palatoglossus (PG) muscle,
palatopharyngeal (PP)
muscle, superior constrictor
(SC) muscle, buccinator (B)
muscle]
SC
PP
SC
PG
SC
B
Internal carotid artery
Pterygomandib
raphe
350
PG
Tonsil
https://t.me/med1917
endoscope, as per the operator’s choice, is introduced into
the middle arm. In the da Vinci Si system, the 5-mm
EndoWrist® spatula tip monopolar cautery is used to dissect
and is usually placed ipsilateral to the cancer or the surgeon’s
dominant hand. The 5-mm Maryland dissector is used to
provide counter traction and grasp the specimen. One of the
senior authors prefers the 8-mm bipolar Maryland because in
most cases it provides superior haemostasis without signicantly impairing access or vision. Both arms are docked at a
30–45° angle from the central arm. If the Xi system is being
used, the authors’ preference is to use the 8-mm monopolar
scissors to dissect and the 8-mm bipolar Maryland on the
second arm. The surgeon sits at the remote console controlling the robotic arms, and an assistant is stationed at the bedside to provide further counter-traction, suction and
assistance with haemostasis, including appropriate surgical
clip application when required. Traction and simultaneous
suction can be provided with paediatric metal Yankauers,
which are narrower in diameter and have the appropriate curvature to retract the oropharyngeal soft tissue.
35.4.1 Lateral Oropharyngectomy
An incision is made through the buccal mucosa at the pterygomandibular raphe and extended cranially through the soft
palate mucosa with the superior limb of the incision extended
more laterally (Fig.35.2).
At the most superior and lateral point, a deep plane is
developed between the medial pterygoid muscle and the
superior constrictors, allowing identication and entry into
the PFS.The Maryland® is used to retract the superior constrictor medially, while the monopolar dissector is used to
bluntly dissect the parapharyngeal fat laterally, away from
the specimen.
The incision is continued superiorly to the point where
both the palatoglossus and palatopharyngeus muscles interdigitate. Care must be taken to take adequate cuff of tissue
because retraction of the muscle, once cut, can expose the
superior pole of the tonsil and lead to a positive or close margin. Depending on the extent of tumour, the incision is
extended lateral to the uvula, and a through-and-through
incision is made into the nasopharynx (Fig.35.3). This plane
is made contiguous with the parapharyngeal space, and
heading posteriorly to the prevertebral fascia, the specimen
is mobilised. Progressive dissection inferiorly, in a plane lateral to the constrictors, will deliver the specimen into the
oropharyngeal lumen.
As the dissection will usually proceed from lateral to
medial, there is a potential risk of inadvertently resecting
more than the required amount of posterior pharyngeal
mucosa.
S. Siddiq et al.
SC
PPF
MP
PG
PP
Fig. 35.3 The superior tonsillar pole is mobilised with adequate cuff
of soft palate and the plane of dissection continues deep to the superior
constrictor using blunt dissection to sweep the parapharyngeal fat laterally [parapharyngeal fat (PPF), medial pterygoid (MP) muscle, palatoglossus (PG) muscle, palatopharyngeal (PP) muscle, superior
constrictor (SP) muscle]
To precisely determine the medial limit of the resection,
index cuts are made early on the posterior pharyngeal mucosa
only (Fig.35.4), ensuring an adequate oncological margin.
The identication of the parapharyngeal fat pad (lateral
pharyngeal fat pad) is key to protecting the underlying internal carotid artery (ICA). The fat pad is bluntly dissected off
the constrictors (to avoid exposure of the ICA)) and the styloglossus muscle in a sweeping action with the spatula tip
from a medial to lateral direction. During this phase of the
dissection, small arteries may be encountered that may
require control, including the tonsillar artery and branches of
the ascending palatine and pharyngeal arteries supplying the
constrictor muscle. The underlying pulsation of the ICA may
be perceived at this point deep to the parapharyngeal fat.
Visualisation of the styloglossus and stylopharyngeus is
achieved with careful posterior dissection between the fascial cover of the constrictor (buccopharyngeal fascia).
During the inferior parapharyngeal dissection, the styloglossus muscle is encountered rst, lying more supercial
and lateral, crossing obliquely from lateral to medial; once
this muscle is dened, the tongue base cuts are completed,
and this muscle transected under direct vision, approximately a centimetre away from the vertical plane of the constrictors (Fig.35.5). This step ensures an oncological margin
from the constrictor at a point where there is a natural dehiscence between the superior and middle constrictors, another
point of an inadvertent close or positive margin. It must be
noted that the larger vessels of the neck lie deep and lateral
to styloglossus muscle. Further dissection encounters the
Соседние файлы в папке Библиотека им академика М.И. Перельмана