endoscopic surgery for cancer larynx

8/3/2019 Endoscopic Surgery for Cancer Larynx

1/13

Mahmoud Ahmed Mahmoud | 846

ENDOSCOPIC SURGERY FOR LARYNGEAL CANCER


2/13

1Table of Contents

Endoscopic Surgery for Laryngeal Cancer

Endoscopic Surgery for Laryngeal CancerTABLE OF CONTENTS

Introduction: ................................................................................................................................... 2

Staging: ............................................................................................................................................ 3

Primary Tumor: ........................................................................................................................... 3

Nodes: ......................................................................................................................................... 5

Metastasis: .................................................................................................................................. 5

Stage Groupings: ......................................................................................................................... 5

Indication: ....................................................................................................................................... 6

Carcinoma in Situ, Microinvasive Carcinoma and Small T1a Carcinomas: ................................. 6

Large T1a and T1b Glottic Carcinomas:....................................................................................... 6

T2 Carcinomas: ............................................................................................................................ 6

T3 Carcinomas: ............................................................................................................................ 6

Infrahyoid Epiglottis: ................................................................................................................... 7

Suprahyoid Epiglottis and False Cord Area: ................................................................................ 7

Supraglottic Carcinomas: ............................................................................................................ 8

Surgical Procedure: ......................................................................................................................... 8

Endoscopic Laser Cordectomy: ................................................................................................... 8

Endoscopic Laser Supraglottic Laryngectomy: .......................................................................... 10

Surgery for Carcinoma of the Epiglottic Border: ....................................................................... 11

Surgery for Vestibular fold Carcinoma: ..................................................................................... 11

Advantages and Disadvantages: ................................................................................................... 11

Advantages: ............................................................................................................................... 11

Disadvantages: .......................................................................................................................... 11

References: ................................................................................................................................... 12


3/13

2Introduction


INTRODUCTION

The surgical, oncologic, and functional principles are the same for minimally invasive surgery as

for more conventional resections. The primary objective is the complete resection of the

tumour while preserving as much function as possible. The principle is to minimize surgical

morbidity while adhering to long-standing oncologic standards.

During transoral laser microsurgery, decisions are made in accordance with the local spread of

the tumour. The tumour extension is often clearly apparent under the microscope, and the

lesion is resected until healthy tissue is found and appropriate safety margins can be

maintained. The goal of complete resection is achieved by variations in the surgical approach

and dissection instrument. In general, a transoral approach is the primary choice, and the CO2

laser under microscopic control is used as a dissecting instrument.

All tumour surgery should adhere to the principle of complete resection with clear surgical

margins that are histologically documented. This involves the cooperation of both the surgeon

and the pathologist. Using a small focal diameter of the laser beam results in minimal

carbonization and is particularly suitable for this application. The histologic assessment of the

resection margins is facilitated by this technique, despite relatively close margins.

The unconventional surgical technique of dissecting through larger tumours during the

resection and removing the tumour in parts allows the surgeon to inspect the surface of the

tissue under microscopic control. There are no indications that the incidence of late regional or

distant metastases increases due to laser incisions through a tumour; this may be explained by

the sealing effect of the lymph vessels, which has been observed in previous investigations.


4/13

3Staging


STAGING

Staging for laryngeal cancer is based on the TNM classification of the American Joint Committee

on Cancer:

Primary Tumor:TX Minimum requirements to assess primary tumor cannot be met

T0 No evidence of primary tumor

Tis Carcinoma in situ

Supraglottis:

T1 Tumor limited to one subsite of supraglottis with normal vocal cord mobility

T2

Tumor involves mucosa of more than one adjacent subsite of supraglottis or

glottis, or region outside the supraglottis (e.g. mucosa of base of the tongue,

vallecula, medial wall of pyriform sinus) without fixation

T3

Tumor limited to larynx with vocal cord fixation and/or invades any of the

following: postcricoid area, preepiglottic tissue, paraglottic space, and/or minor

thyroid cartilage erosion (e.g. inner cortex)

T4a

Tumor invades through the thyroid cartilage and/or invades tissue beyond the

larynx (e.g. trachea, soft tissues of neck including deep extrinsic muscles of the

tongue, strap muscles, thyroid, or esophagus)

T4bTumor invades prevertebral space, encases carotid artery, or invades

mediastinal structures


5/13

4Staging


Glottis:

T1Tumor limited to the vocal cord (s) (may involve anterior or posterior

commissure) with normal mobility

T1a Tumor limited to one vocal cord

T1b Tumor involves both vocal cords

T2Tumor extends to supraglottis and/or subglottis, and/or with impaired vocal

cord mobility

T3Tumor limited to the larynx with vocal cord fixation and/or invades paraglottic

space, and/or minor thyroid cartilage erosion (e.g. inner cortex)

T4a

Tumor invades through the thyroid cartilage, and/or invades tissues beyond the

larynx (e.g. trachea, soft tissues of the neck including deep extrinsic muscles ofthe tongue, strap muscles, thyroid, or esophagus)



Subglottis:

T1 Tumor limited to the subglottis

T2 Tumor extends to vocal cord (s) with normal or impaired mobility

T3 Tumor limited the larynx with vocal cord fixation

T4a

Tumor invades cricoid or thyroid cartilage and/or invades tissues beyond larynx

(e.g. trachea, soft tissues of the neck including deep extrinsic muscles of the

tongue, strap muscles, thyroid, or esophagus)




6/13

5Staging


Nodes:

N0 No cervical lymph nodes positive

N1 Single ipsilateral lymph node 3cm

N2a Single ipsilateral node > 3cm and 6cm

N2b Multiple ipsilateral lymph nodes, each 6cm

N2c Bilateral or contralateral lymph nodes, each 6cm

N3 Single or multiple lymph nodes > 6cm

Metastasis:

M0 No distant metastases

M1 Distant metastases present

Stage Groupings:

Stage

0 Tis N0 M0

I T1 N0 M0

II T2 N0 M0

III T3 N0 M0

T1-3 N1 M0

IVA T4a N0-2 M0

T1-4a N2 M0

IVB T4b Any N M0

Any T N3 M0

IVC Any T Any N M1


7/13

6Indication


INDICATION

Carcinoma in Situ, Microinvasive Carcinoma and Small T1a Carcinomas:

In cases of a biopsy-proven small carcinomas or carcinoma in situ, the entire lesion is excised

with an appropriate resection margin. When tumour invades is found in the resection margin,two treatment strategies are possible: laser surgery or radiotherapy. Its recommended to

repeat laser or conventional surgery because, in most cases where tissue is re-resected from

the tumour margin, this tissue is tumour-free on histopathologic investigation, and

radiotherapy would have been unnecessary. Most experiences indicate that, in general, vocal

function is almost normal following such limited-excision biopsies.

Large T1a and T1b Glottic Carcinomas:

When a clearly superficial lesion infiltrates to a depth of only approximately 2 mm and does not

cover the entire cord (i.e., microcarcinoma), the carcinoma is excised en bloc. When the depth

of infiltration is in doubt, a single incision through the center of the tumour may help to

estimate the depth. The subsequent laser surgical treatment is the same as for small, well

circumscribed lesions. In cases of marginal involvement of the anterior commissure without

subglottic extension, the anterior commissure is resected along with the bilateral cord lesion.

The dissection is carried out along the thyroid cartilage under high magnification of the

operating microscope. Laser surgical resections of carcinomas of the anterior commissure

require a surgeon experienced in this technique because the risk of developing recurrent

disease is more likely in the anterior commissure than in any other localization of the glottis.

T2 Carcinomas:

For all T2 carcinomas of the glottis, primary laser surgery is advocated regardless of the pattern

of tumour spread. A surgeon with wide experience in laser surgery is essential. Superficially

spreading carcinomas are ideally suited for laser surgery. Even if they cover vast areas of the

endolarynx, they can be resected completely with a partial mucosectomy of the larynx if the

carcinoma can be exposed adequately. The excision can be performed in several pieces, and the

basal surfaces should be stained with blue ink for better orientation of the pathologist. Exact

topographic descriptions on the pathology request form are important and should be copied

onto patient charts. Additionally, the exact origin of the individual specimen must be noted in a

schematic drawing of the larynx.

T3 Carcinomas:

Currently, the majority of resectable carcinomas are treated with conventional surgery.

However, laser surgical resection is possible even for large tumours if they can be exposed

adequately and if the surgeon has the required training in laser surgery. For these advanced


8/13

7Indication


tumours of the glottis, incisions are placed through the bulk of the tumour to divide it into

smaller portions, laterally onto the thyroid cartilage and inferiorly onto the superior surface of

the cricoid cartilage. Incisions follow the extensions of the tumour and are placed deeply into

the musculature until a tissue layer is encountered that reacts normally to the laser light under

the microscope. If the musculature is invaded up to the perichondrium, the tumour can beresected by dissecting along the inner table of the thyroid cartilage. Suspected infiltration of

the thyroid cartilage or definite penetration through parts of the cartilage is included in the

resection. A specimen resected from the neighboring prelaryngeal soft tissues can be used to

verify the completeness of the resection. The resection of extended carcinomas should be

performed by a surgeon experienced in laser surgery to avoid an incomplete resection that

would adversely affect the patient's prognosis. Conventional surgery is preferred where an

experienced surgeon is unavailable.

Infrahyoid Epiglottis:

The depth of tumour infiltration in the area around the petiole is difficult to assess

preoperatively. There may be considerable difficulty in distinguishing between a T1 tumour and

a T3 lesion (infiltration of the pre-epiglottic space). To determine the extent of the carcinoma to

the preepiglottic space, we usually split the suprahyoid epiglottis sagitally. The bivalved

laryngoscope is subsequently advanced, thus revealing the surface of the dissection plane

through the epiglottic cartilage as well as the pre-epiglottic fat and the laryngeal surface of the

infrahyoid epiglottis with the tumour. The tumour is then dissected in a sagittal plane. The

dissection proceeds in an inferior direction. Depending on the extent of the tumour, horizontal

cuts are placed through the bulk of the lesion. If the thyroid cartilage or one of the arytenoid

cartilages is infiltrated by tumour, it is included in the resection. During the resection of parts of

the thyroid cartilage, care is taken to avoid damage to the extralaryngeal vessels. If the tumour

has broken through the thyrohyoid membrane, it is followed as far into the neck as possible.

The resection can reach all the way into the subcutaneous tissue of the neck. Persistent

functional impairments are not anticipated with this surgery.

Resection of advanced carcinomas requires attention to postoperative function. Resection of

one arytenoid cartilage is not associated with long-lasting functional impairment; however, if

both arytenoids are resected, deglutition without aspiration is usually not possible. Additional

difficulties may occur if further resections in the area of the base of the tongue are required. Asalready noted, the resection of extended carcinomas is reserved for surgeons with extensive

experience with laser surgery.

Suprahyoid Epiglottis and False Cord Area:

Technically, tumours in this location can be easily excised. Wide resection margins can be

achieved without functional implications as in the case of glottic lesions.


9/13

8Surgical Procedure


Supraglottic Carcinomas:

Small, well-circumscribed tumours of the supraglottis can be resected in one piece, similar to

small lesions on the vocal cord.

SURGICAL PROCEDURE

Endoscopic Laser Cordectomy:

The procedure begins with the orotracheal intubation with a laser-safe endotracheal tube. The

patients eyes are then taped and padded and a head drape and upper tooth guard is applied.

When the patient is fully relaxed and sufficiently anaesthetized, a largest possible laryngoscope

is introduced to get a good view of larynx.

Before introducing the laryngoscope, the patients head is fully extended, and the laryngoscope

is introduced between the endotracheal tube behind and lower jaw in front. Undervisualization, laryngoscope is gently pushed forwards following the endotracheal tube between

the epiglottis and the tube until the point reaches the petiole of epiglottis. If laryngoscope is

passed too deeply into the larynx, both the vestibular fold and vocal folds are displaced

laterally, whereas if the scope is not passed deeply enough the vestibular folds obscure the

vocal cords. Once the laryngoscope is correct position, the chest holder is put in place to fix the

scope in position. After exact adjustment of the scope, both vocal cords can be seen as far as

the apex of vocal process. Once the laryngoscope is in the desired position, the light carrier is

removed and an operating microscope is used.

The patients head and face are protected with moist towels and the operating microscope,

which is fitted with a microspot carbon dioxide laser and 400 mm lens is brought into position.

To protect the endotracheal tube cuff, a moist cottonoid sponge is placed in the subglottis.

Dissection is begun posteriorly and laterally. Medial retraction of the edge of the lesion shows

the plane of dissection as the surgeon dissects anteriorly and inferior edge is resected at the

end. A curved trajectory that parallels the contour of the normal vocal fold is used, and the

depth of the excision is tailored to the lesion.

The 30 or 70 angle telescope introduced through laryngoscope can be used with the

advantage of examining the laryngeal surface of epiglottis, lateral wall of larynx, and subglotticspace.


10/13

9Surgical Procedure


Different Types of Cordectomy:

Type I: Subepithelial Cordectomy:

This involves the resection of vocal fold epithelium, passing through the superficial layer of the

lamina propria. It is performed for premalignant lesions and lesions that show malignant

transformation. Usually entire vocal cord epithelium is resected and in rare cases, clinically

normal epithelium may be preserved. Since subepithelial cordectomy ensures histopathological

examination of entire vocal cord, the main role of this surgical procedure is diagnostic. This

procedure can also be therapeutic if histological results confirm hyperplasia, dysplasia, or

carcinoma in situ without signs of microinvasion.

Type II: Subligamental Cordectomy:

This is indicated for cases of microinvasive carcinoma or severe carcinoma in situ with possible

microinvasion. In this procedure vocal cord epithelium, Reinke space, vocal ligament are

resected by cutting between the vocal ligament and vocalis muscle. The resection may extendfrom the vocal process to the anterior commissure and vocalis muscle is preserved as much as

possible.

Type III: Transmuscular Cordectomy:

This procedure is indicated for small superficial lesions of the mobile vocal folds that reaches

the vocalis muscle and without deeply infiltrating it. This involves the resection of epithelium,

lamina propria and the part of vocalis muscle. The resection may extend from the vocal process

to the anterior commissure. In some cases, partial resection of the ventricular fold may be

required for adequate visualization of the vocal fold

Type IV: Total or Complete Cordectomy:

This procedure is indicated for T1a lesions infiltrating the vocalis muscle. The resection extends

from the vocal process to the anterior commissure and attachment of vocal ligament to the

thyroid cartilage should be cut. The depth of the surgical margins reaches the internal

perichondrium of the thyroid cartilage and sometimes perichondrium is included with

resection.

Type V: Extended Cordectomy

Type Va: Extended Cordectomy encompassing the contralateral vocal fold:

This surgical approach was meant to include the anterior commissure and, depending on the

extent of tumor, either a segment or the entire contralateral vocal fold. This procedure is now

replaced by type VI cordectomy.


11/13

10Surgical Procedure


Type Vb: Extended Cordectomy encompassing the arytenoids:

This procedure is indicated for vocal fold carcinoma involving vocal process or arytenoid

cartilage posteriorly. For this type of resection, arytenoid cartilage should be mobile, and the

cartilage is partially or fully resected.

Type Vc: Extended Cordectomy encompassing the ventricular fold:

This procedure is indicated for ventricular cancers or trans glottis cancers that spread from

vocal fold to the ventricle. This involves the resection of ventricular fold and Morganis

ventricle.

Type Vd: Extended cordectomy encompassing the subglottis:

This procedure can be used for selected cases of T2 carcinoma with limited subglottic extension

without cartilage invasion.

Type VI cordectomy:

This procedure is indicated for cancer originating in the anterior commissure involving one or

both the vocal cords, without infiltrating the thyroid cartilage. The surgery comprises anterior

commissurectomy with bilateral anterior cordectomy. If the tumor is in contact with cartilage,

resection can encompass anterior part of thyroid cartilage. Resection of the anterior

commissure may include the subglottis mucosa and cricothyroid membrane, because cancers of

anterior commissure tend to spread toward the lymphatic vessels of the subglottis.

The pharynx and teeth should be checked for damage before extubating from anesthesia.

Endoscopic Laser Supraglottic Laryngectomy:

The technique of transoral laser resection of supraglottic cancer contradicts the classic rules of

oncological surgery because in many cases tumors are sectioned and removed piecemeal. It is

possible to do so because the hemostatic effect of the CO2 laser and the operating microscope

allow the surgeon to detect the boundary between tumor and healthy tissue. Optimal exposure

and visualization of the supraglottic region is critical for safe tumor resection. Ordinary tubular

laryngoscopes are not suitable for procedures in this area. Bivalved laryngoscopes with

spreadable blades are necessary. The blades may be separated by angulation or parallel

distraction, thus providing flexibility in exposing various sites. Numerous adjustments of the

position of the laryngoscope during surgery are usually necessary to achieve good visualizationof the tumor and of the surrounding healthy tissue. Smaller tumors along the free margin of the

epiglottis and of the aryepiglottic fold can be excised in one piece as an excisional biopsy.

Larger tumors require piecemeal resection, with consequent sectioning of the neoplasm.

Specimens are labeled as to location and sent for frozen section, with particular attention to

the resection margins. Several techniques have been described to improve access and visibility.

The epiglottis may be initially divided sagitally or horizontally and then retracted into a plane


12/13

11Advantages and Disadvantages


tangential to the laser beam. When infra-hyoid tumor extension is present, the pre-epiglottic

space must be completely removed. The resection may be extended to include the false vocal

cords and the paraglottic space. If cancer approaches the arytenoid cartilage, the arytenoid

itself can be transected or resected completely. Consequently, the mucosal and endolaryngeal

area that can be extirpated is comparable to that of the classic transcervical HSL, withoutresection of thyroid cartilage.

Surgery for Carcinoma of the Epiglottic Border:

Small T1 epiglottic carcinoma can be excised by CO2 laser much like a vocal cord lesion. This

technique provides an en bloe removal with a safety margin of several millimeters. The patient

has no functional deficits (swallowing, respiration) and can be released from hospital the gay

after surgery.

Surgery for Vestibular fold Carcinoma:

A safe resection is performed using the same technique for epiglottic carcinoma. The incision

may continue in the pre-epiglottic space down to the hyoid and the upper rim of the thyroid

cartilage.

ADVANTAGES AND DISADVANTAGES

Advantages:

o May be extended to include tumors involving hypopharynx/oropharynx.o Typically does not require tracheotomy.o Reduced incidence of aspiration pneumonia.o Preservation of superior laryngeal neurovascular bundle, preserving sensation to larynx.o Lower incidence of pharyngocutaneous fistulas.o Faster rehabilitation of swallowing.o Shorter hospital stays.

Disadvantages:

o Large tumors that result in limited exposure via laryngoscope may be better addressedvia an open approach.

o More extensive endoscopic resections result in a higher risk of postoperative aspiration.


13/13

12References


REFERENCES

Malignant Tumors of the Larynx and Hypopharynx. Cummings- Otolaryngology- Headand Neck Surgery. 4th ed., Mosby, 2005.

Malignant Laryngeal Lesions. Lawani- Current Diagnosis and Treatment inOtolaryngology- Head and Neck Surgery. McGraw-Hill and Lange, 2004.

Surgery for Supraglottic Cancer. Myers- Operative Otolaryngology Head and NeckSurgery Vol. 1. 1st ed., Saunders, 1997.

Surgery for Glottic Carcinoma. Myers- Operative Otolaryngology Head and Neck SurgeryVol. 1. 1st ed., Saunders, 1997.

The Larynx. Lore and Medina- An Atlas of Head and Neck Surgery. 4th ed., Elsevier,2005.

Lefebre J, Chevalier D, Luboinski B, Kirkpatrick A, Collette L, Sahmoud T. LarynxPreservation in Pyriform Sinus Cancer: Preliminary Results of a European Organization

for Research and Treatment of Cancer Phase III Trial. Journal of the National Cancer

Institute. Jul 1996. 88(13): 890-899.

endoscopic surgery for cancer larynx

Documents