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n. 5/2000
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Abstract |
Giovanni Motta
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Malignant
laryngeal neoplasias generally consist of carcinomas. Essential
requirements in order to guarantee the necessary validity to the surgical
operations discussed in this paper are their correct indication and the
employment of adequate techniques which will enable a rigorous excision of
the pathological processes and at the same time limit damages to the
laryngeal structures. The main
advantages which laser surgery generally offers in the treatment of laryngeal
pathological processes are: - the possibility
of carrying out with absolute precision the excision of benign or malignant
laryngeal neoplasias, thus allowing better functional results; - the quickness
of operations and the consequent reduction in surgical traumas, as well as
the favourable repercussions on the postoperative course; - a shorter stay
in hospital and therefore less suffering for the patient and significant
sociomedical savings. In the
oncological sector in particular, CO2 laser surgery also allows operations by
endoscopy which, if properly performed, besides offering the above mentioned
advantages, guarantee a high percentage of recoveries; these results do not
differ (obviously taking into account the seat and size of the tumour) from
those achieved with traditional, and markedly more traumatizing, techniques. Introduction Very often the
word 'laser' (which stands for Light Amplification by Stimulated Emission of
Radiation) is associated in people's imagination with science-fiction
weapons; in fact, within the field of endoscopic surgical techniques, it is
an advanced technology, which makes it possible to achieve substantial
success. In laryngeal
surgery, in particular, CO2 laser is employed to cut, dissect and vaporise
tissues affected by different kinds of pathological processes, by using, as a
surgical access, natural ducts thanks to the employment of direct
microlaryngoscopy. Even though it
is often necessary to operate on very restricted areas, the related surgical
techniques are extremely precise, thanks to the direct control of the
surgical field granted by the microscope: it is therefore possible to avoid
much more aggressive, demanding and traumatizing operations. (picture 1). As we all know,
the larynx plays a very important role: - in breathing,
by enabling air to pass into the trachea and lungs; - in
deglutition, by preventing food from entering the respiratory tract; - in phonation,
by giving rise to the basic vocal sound, which is then elaborated in the
resonance cavity and by the articulating organs, thus enabling verbal
communication. This organ can
be affected by different kinds of pathological processes: inflammatory,
tumorous, malformational, post-traumatic, etc.; these prejudice its functions
to a lager or smaller extent and usually call for surgical treatments which
are often very complex and lead to seriously disabling consequences: among
these we mention total laryngectomy, which is generally performed in the
event of large tumours: this involves the removal of the larynx and, among
the other consequences, the loss of speech by means of natural mechanisms. In laryngeal
microsurgery, CO2 laser was first employed in 1972, with the use of equipment
designed by Polany, an authoritative physicists from the Fermi school. After the first
experiences conducted in Boston by Strong e Jako (1970), CO2 laser became
widespread in a number of countries. Its success in the field of laryngeal
surgery is certainly also due to the contribution of the Neapolitan School,
which clarified its indications and suggested new techniques to improve its
employment: the case histories covered by our experience are over 3000 and
relate to patients who have undergone surgery over the last 20 years. Our
experience in the field is among the ones covering the highest number of
cases in the world, especially as regards the treatment of laryngeal
tumours. The employment
of CO2 laser in laryngeal microsurgery has specific indications, chiefly in
the treatment of the following pathologies: - benign
neoformations implanted in the mucous membrane (such as nodules, polypi,
Reinke's edemas, granulomas, etc.) or located in the laryngeal wall (such as
cysts, fibromas, amyloidosis, etc.), - potentially
degenerative epithelial lesions: dyskeratosis, verrucae, dysplasias,
adult-age papillomas; - children's
papillomatosis; -
laryngotracheal stenosis; - bilateral
abduction paralysis of vocal cords; - laryngeal
amyloidosis; - glottic and
supraglottic carcinomas (T1-T2-T3). The surgical
techniques and the related instruments employed by us are substantially those
proposed in 1968 by Kleinsasser for laryngeal microsurgery; in time, these
have obviously been reviewed and adjusted (especially as surgical techniques
are concerned) owing to the employment of laser and to certain specific objectives
set for individual cases. The basic
surgical timings involved in all the operations carried out with the
technique illustrated hereby are the following (Picture1): - the patient is
placed on the operating table lying on his/her back, with his/her head
stretched out and the nape of the neck on a headrest; - general
anaesthesia follows the traditional procedures; it should however be
mentioned that the endotracheal tubes which are generally employed, if struck
by a laser beam, can melt or catch fire; they therefore have to be protected
by an adhesive tape in self-reflective aluminium or else be replaced with
other tubes in laser-resistant material; - adequate
measures are taken to protect the patient from the laser beam: they mainly
consist in placing a damp cloth over the face and eyes of the patient and in
introducing a small tampon of damp gauze in the tracheal lumen, to avoid
lesions of the mucous membrane or damage to the small rubber bulb placed at
one end of the tube employed for anaesthesia; - proper
cautionary measures are also taken to protect the staff present in the
operating theatre from the laser beams. In our paper we
shall be taking into account the opportunities offered by laryngeal
microsurgery employing CO2 laser in the treatment of laryngeal carcinomas. Indeed, among
the pathological cases affecting the larynx, carcinomas represent the largest
sector as regards indications and opportunities to employ this type of
surgery, taking into account their high incidence and the noticeable
advantages this technique offers as compared to all the other traditional
methodologies currently employed. It should however be stressed that, also in
the case of these pathological processes, the prerequisites for the success
of the operations hereby described are a correct selection of the cases in
which this treatment is indicated and the employment of correct techniques.
Malignant tumours affecting the larynx are divided into glottic-hypoglottic
or supraglottic forms, depending on whether the neoplasia has originated in
the true vocal cords area and underneath, or else in the area placed above
the vocal cords (Picture 2). In order to
standardize the treatment and classification criteria employed with the
neoplasias in question, reference is generally made to TNM classification,
proposed by UICC: this enables a categorization of neoplastic lesions based
on the initial size of the lesion (T1, T2, T3, T4), on the possible presence
of metastasis in the lymphonodi of the neck (N1, N2, N3) and finally on the
presence or absence of distant secondary localizations (M0 -M1). As regards the
indications of the surgical techniques based on the employment of CO2 laser,
we have maintained, ever since 1982, that by taking proper steps, it is
possible to operate with success, with its employment through the natural
ducts and the control of the microscope, not only in the case of laryngeal
tumours affecting limited segments of the true vocal cords, but also in cases
in which the neoplasia has expanded to relatively large areas of the
glottic-hypoglottic area and of the supraglottic area, provided the motility
of the affected organs is not seriously damaged and provided there are no
secondary localizations in the regional lymphonodi nor distant metastasis. More
specifically, we believe that all laryngeal tumours T1-T2 N0 M0 can be
successfully treated by means of such techniques. Furthermore,
contrary to the opinion of other authors, we believe that the indications for
this surgery also include glottic neoplasias of both vocal cords affecting
“the anterior commissure” (T1b, bilateral T2). We finally wish
to mention the high percentage of recoveries also observed in - accurately
selected - cases with larger tumours, with a damaged laryngeal motility, that
is those classified as T3N0M0. From a technical
point of view, all the operations carried out by endoscopy with CO2 laser
must always comply with the rigorous radicalism prescribed by oncological
surgery; in other words, endoscopic operations should involve the removal of
the tumour with an adequate margin of surrounding undamaged tissue, in line
with the dictates of traditional laryngeal surgery. Our observations
relating to 605 patients followed up for a period of at least 5 years, enable
us to make a number of remarks and considerations which are certainly of
interest, taking into account the number of cases treated and the long period
of time in which our experience has developed. The surgical
techniques, proposed by us ever since 1982, can be summarised as follows: Glottic
tumours (Picture 3, 4a-b-c-d-e) - Cordotomy and
simple cordectomy (T1a) - Widened
cordectomy (T2 monol.) - Bilateral
cordectomy (T1b) - Widened
bilateral cordectomy (bil. T2, T3). Supraglottic
Tumours (Fig.5, 6a-b-c-d) -
Epiglottidectomy. Removal of the false vocal cord, of a lager or smaller part
of the epiglottis and of the aryepiglottic fold on one side (T1). - Widened
cordectomy (T2). - Horizontal
supraglottic laryngectomy (T3). Our results,
which are synthetically reported in table 1 and 2 for glottic tumours and in
table 3 for supraglottic tumours, have been evaluated by calculating, over a
5-year follow-up period, global actuarial survival and correct actuarial
survival. The global actuarial survival figure takes into account all the
deaths taking place irrespective of the causes which had led to the them; the
correct actuarial survival figure is also based on statistical data, taking
into account the possibility that a certain number of deaths might have
occurred for reasons which are unrelated to the tumorous process. In summary, we
can state the following: 1) in unilateral
tumours T1-T2, our results are virtually equivalent to those reported by the existing
literature on patients operated by means of traditional techniques; however
this is quite obvious, since the surgical methodologies employed by us comply
with the radicalism applied in carrying out traditional surgical operations
(that is from the outside); compared to these methodologies, however, the
endoscopic technique provides significant advantages, as we will explain
further on; 2) as regards
patients with carcinoma T1b and bilateral T2, a number of authors (Bonetti,
Davis, Riddington) believe that the involvement of the anterior commissure
represents a contraindication in the treatment of the neoplastic process by
direct microlaryngoscopy; this has led various surgeons to adopt for these
neoplastic forms more radical surgical techniques, with the aim of
guaranteeing the complete removal of the neoplasias together with the
cartilaginous skeleton of the commissure (frontolateral laryngectomy,
horizontal glottectomy, anterior frontal laryngectomy). We do not share
this opinion: the results put forth show that, by means of a proper
micro-endoscopic surgical technique, with the aid of CO2 laser, it is not
only possible to perfectly dominate the region of the anterior commissure,
but also to carry out a radical excision of such neoplasias, achieving
survival percentages equivalent to those reported by the literature available
on the subject for patients operated by means of more aggressive surgical
procedures, which obviously involve a longer postoperative course and a
greater risk of complications. Endoscopic
surgery carried out with CO2 laser in laryngeal carcinomas offers, as
compared to traditional surgery, the following advantages: - execution of
the operation through the natural ducts; - rapidity of
the operation and hence a more limited trauma and a low incidence of
complications; - possibility of
generally avoiding tracheotomy (which was performed only in 1,1 % of our
cases); - preservation
of the integrity of the cartilaginous skeleton (in the event of recurrences,
this reduces the risk of spreading of the tumour); - improved
functional results, since the employment of the surgical microscope makes it
possible to limit exeresis to the areas infiltrated by the tumour and to
those which are immediately adjacent, whereas the areas which are not
affected by the neoplasia are certainly saved; - quick
postoperative course and hence very short stays in hospital, with consequent
positive psychological results for the patient, as well as reduced
sociomedical costs. We would like to
mention, at this stage, that, in a recent study conducted in the United
States, Myers found that for T1 cordal tumours the expenses related to the
surgical treatment by laryngoscopy with the aid of CO2 laser amounted to
about 50% of the expenses involved by a hemilaryngectomy operation or by a
cycle of radiotherapy: it was extrapolated that the employment of CO2 laser
in laryngeal microsurgery would involve in the United States a saving of 2.4
million dollars for every 100 patients suffering from pathological processes
susceptible of such a treatment. The above
therefore proves that the surgical techniques adopted by us, besides offering
from a survival point of view guarantees which are equivalent to or even
greater than those offered by traditional methodologies, also offer
significant surgical and functional advantages, with obviously positive
repercussions from a socio-economical point of view. In fact, the
success achieved with the techniques illustrated hereby and improved and more
precise information to patients, have led over the last few years an ever
increasing percentage of people affected by phonation disorders to consult a
specialist in good time, thus favouring early diagnosis of any neoplastic
processes and the resort to conservative surgery. In this regard,
we have noticed in our Institute an evident reduction in the number of total
laryngectomy operations which, even though they make it possible to save the
lives of many patients, on the other hand involve severe disabling
consequences, owing to the loss of the voice and to the creation of permanent
tracheostomy. This datum represents a further demonstration of the validity
of the surgical trends illustrated above. Conclusions In laryngeal
carcinomas, the endoscopic methodologies based on the employment of CO2 laser
not only lead to a percentage of recoveries which is equal or even higher
than those achieved by means of traditional techniques, but, as compared to
these, offer significant advantages, among which the following should be
stressed: - the high precision with which the
related surgical exeresis can be carried out; - the
possibility of treating the pathological processes by endoscopy, that is
through natural ducts, without resorting to cutaneous incisions, with
operations which are generally less traumatizing and involving more limited
risks; - a quicker
postoperative course compared to traditional surgical techniques and
therefore a lower incidence of complications and less suffering for the
patients; - reduced costs
for society. The data illustrated
in this paper, which relates to a working experience achieved over a period
of 20 years, demonstrate in any case that the success of the surgical
methodologies illustrated hereby depends on the precision of the related
indications and on the employment of proper surgical techniques. Giovanni Motta Erik Esposito Dip. Clinica Otorinolaringoiatria Univ. Federico II Napoli |
Giovanni Motta
Fig. 5: Excision schemes of
supraglottic tumors
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