Total laryngectomy

Although it is an excellent oncologic procedure and secures good swallowing without aspiration, it has disadvantages such as having a permanent tracheostomy; that verbal communication is dependent on oesophageal speech, and/or tracheoesophageal fistula speech or an electrolarynx; hyposmia; and the psychological and financial/ employment implications. Even in the best centers, about 20% of patients do not acquire useful verbal communication.


What will be the tumour resection lines?
As the initial incisions into the pharynx are done from externally without having the tumour in view, the surgeon must carefully assess the valleculae, base of tongue and the pyriform fossae for tumour involvement, to avoid cutting into tumour when entering the pharynx. Involvement of the base of tongue may also prompt the surgeon to opt for a retrograde laryngectomy (commencing the laryngectomy at the tracheostomal end of the specimen). In the absence of CT or MRI imaging, one can palpate and assess tumour involvement of the pre-epiglottic space and base of tongue under general anaesthesia by placing one index finger in the valleculae, and the other on the skin of the neck just above the hyoid bone. The fingers should normally virtually meet, unless there is tumour in the preepiglottic space or vallecula or base of tongue.

Is thyroidectomy required?
Both hypothyroidism and hypoparathyroidism are common sequelae of total laryngectomy, particularly following postoperative radiation therapy, and may be difficult to manage in a developing world setting. Twenty-five percent of laryngectomy patients become hypothyroid following hemithyroidectomy; and 75% if postoperative radiation is added. However, both thyroid lobes may be preserved unless Level 6 nodes need to be resected with subglottic and pyriform fossa carcinoma, or when there is intraoperative or radiological evidence of direct tumour extension to involve the thyroid gland.

Will a pectoralis major flap be required?
A capacious pharynx is essential for good swallowing and fistula speech. Should tumour involve the hypopharynx, especially when it extends distally towards the cricopharyngeus, then the expertise must be available to possibly augment the pharyngeal repair with a pectoralis major flap. Pectoralis major muscle flaps are also frequently used to overlay the pharyngeal repair with salvage laryngectomy to encourage spontaneous closure of pharyngo-cutaneous fistulae when they occur.

Is elective neck dissection required?
With advanced laryngeal squamous cell carcinoma requiring laryngectomy, elective lateral neck dissection (Levels 2-4), either ipsilateral (glottic carcinoma) or bilateral (supraglottic, medial wall of pyriform fossa, bilateral glottic carcinoma) is recommended, with con-version to modified neck dissection should cervical metastases be found intraoperatively. Level 6 is included in subglottic and pyriform fossa carcinoma to clear the paratracheal nodes.

Is the patient suitable for tracheooesophageal speech?
This decision is based on assessment of cognitive function, motivation, financial ability to pay for replacement speech prostheses, and proximity to speech services.

Are there synchronous primaries or distant metastases?
Total laryngectomy has significant morbidity and should only be done if panendoscopy and CXR/CT chest exclude metastases or 2 nd primaries.

Intubation:
The operation is done under general anaesthesia. The ENT surgeon must be present to assist with a possibly difficult intubation. If a difficult intubation is anticipated, then either do an awake tracheostomy, or infiltrate skin and trachea with local anaesthesia/vasoconstrictor, in preparation for a possible emergency tracheostomy.
Preoperative tracheotomy: Tracheotomy may have been required for airway obstruction. It is not an independent indication for postoperative radiation therapy unless tumour was entered at the time of tracheotomy. If a tracheostomy has already been done, then ask the anaesthetist to reintubate through the larynx with an orotracheal tube once the patient has been anaesthetised as this facilitates dissection in the lower neck and speeds up the surgery.
Perioperative antibiotics: Commence perioperative antibiotics before putting knife to skin, and continue for 24 hrs.

Surgical anatomy
Figures 1 & 2 illustrate all the muscles that will be divided during laryngectomy.

Surgical steps
Positioning: Extend the neck

Incisions for apron flap (Figures 3a, b)
The horizontal limb of the flap is placed approximately 2cms above the sternal notch. An ellipse of skin around a preexisting tracheostomy is included with the resection. With a simple laryngectomy the vertical incisions are placed along the ante-rior borders of sternocleidomastoid muscles. For a laryngectomy with neck dissection(s), either a wider flap overlying the sternocleidomastoid muscles is made (Figure 3a), or a narrow flap with inferolateral extensions is made (Figure 3b). The latter has the disadvantage of a trifurcation which is more prone to wound breakdown and exposure of the major cervical vessels. • Cut through the superficial layer of investing fascia and platysma muscles. The platysma is often absent in midline. Take care not to injure the external and anterior jugular veins • Elevate the apron flap in a subplatysmal plane, remaining superficial to the external and anterior jugular veins • Dissect the flap superiorly up to approximately 2cms above the body of the hyoid bone . It is a broad, thin muscle, so take special care not to injure the thyroid gland and its rich vasculature which is immediately deep to muscle • Carefully elevate and reflect the superior cut end of the sternothyroid muscle from the thyroid gland using electrocautery dissection ( • Divide the inferior pharyngeal constrictor muscle and thyroid perichondrium with electrocautery at, or just anterior to the posterior border of the thyroid ala ( Figure 13) • Strip the lateral wall of the pyriform fossa off the medial aspect of the thyroid ala in a subperichondrial plane with a swab/sponge held over a fingertip, or with a Freer's elevator, only on the side of the larynx opposite to the cancer (Figure 14). On the side of the cancer, this step is omitted to ensure adequate resection margins. The surgeon then crosses to the opposite side of the patient and repeats the above operative steps.

Suprahyoid dissection
The following description applies to laryngeal cancer not involving the pre-epiglottic space, vallecula or base of tongue. When tumour does involve vallecula, pre-epiglottic space and/or base of tongue, then the pharynx is entered via the opposite pyriform fossa or a retrograde laryngectomy is done, commencing the dissection inferiorly at the tracheostomy (see later) • Identify the body of the hyoid bone • Remember that the hypoglossal nerves and lingual arteries lie just deep to the greater cornua/horns of the hyoid bone • Divide the suprahyoid muscles with electrocautery along the superior border of the body of the hyoid bone • The hyoglossus and middle constrictor muscles are next released from the greater cornu with diathermy ( Figure  16) • Divide the soft tissue on the medial aspect of the tips of the greater cornua of the hyoid with scissors to free the greater cornua of the hyoid bilaterally ( Figure 17). Hug the inner aspect of the greater cornua to avoid the hypoglossal nerves. If a neck dissection has been done, the hypoglossal nerves will already be visible • Dissect transversely with diathermy along the superior margin of the body of the hyoid bone, and along the superior margin of the pre-epiglottic space • Identify the hyoepiglottic ligament in the midline

Tracheostomy
• A tracheostomy is done at this stage to mobilise the larynx and to facilitate the laryngeal resection • Ask the anaesthetist to preoxygenate the patient • Incise the trachea transversely between the 3 rd /4 th /5 th tracheal rings or below a preoperative tracheostomy • With a small trachea, incise the lateral tracheal walls in a superolateral direction to bevel and enlarge the tracheostoma • Place a few 3-0 vicryl half-mattress sutures between the anterior wall of the transected trachea and the skin to approximate mucosa to skin • Puncture and deflate the cuff of the endotracheal tube, and cut the tube in the pharynx, and remove the distal end of the tube through the pharyngotomy • Insert a flexible endotracheal tube e.g. armoured tube into the tracheostoma. Avoid inserting the tube too deeply as the carina is quite close to the tracheostoma. Fix the tube to the chest wall or drapes with a temporary suture so that it does not become displaced, attach the sterile anaesthesia tubing and resume ventilation

Laryngeal resection
• Inspect the subglottis through the tracheostoma to ensure that the tracheal tumour resection margin is adequate • Move to the head of the operating table • Retract the epiglottis and larynx anteriorly through the pharyngotomy, and inspect the larynx and the tumour • Commence laryngeal resection contralateral to the tumour using curved scissors with points located anteriorly/ upwards to avoid inadvertently resecting too much pharyngeal mucosa • Cut along the lateral border of the epiglottis on the less involved side, to expose the hypopharynx • Repeat this on the side of tumour with at least a 1cm mucosal margin around the tumour • On the less involved side, cut through the lateral wall of the pyriform fossa and hug the arytenoids and cricoid to preserve pyriform sinus mucosa (Figure 20). The superior laryngeal neurovascular pedicle is transected if not previously addressed • Repeat on the tumour side  • Extend the incision to the pyriform fossa contralateral to the cancer • Once the cancer can be seen through the pharyngotomy, incise the pyriform fossa mucosa on the involved side • By placing an index finger across the vallecula to palpate the upper extent of the cancer one can proceed to transect the base of tongue with an adequate margin

Pharyngo-oesophageal myotomy
• Optimising speech and swallowing requires a capacious and floppy pharynx • Always perform a pharyngoesophageal myotomy to prevent hypertonicity of the pharyngoesophageal segment • Insert an index finger into the oesophagus (Figure 28) • With a sharp scalpel, divide all the muscle fibres down to the submucosa, and distally to the level of the tracheastoma ( Figure 28). The myotomy may be done in the midline or to the side

Tracheo-oesophageal fistula
• Tracheo-oesophageal speech is the best form of alaryngeal communication • A tracheo-oesophageal fistula is created before closing the pharynx • Pass a curved artery forceps through the pharyngeal defect along the oesophagus and tent up the anterior wall of oesophagus/posterior tracheal wall 5-10mm below the superior margin of the tracheostoma. Placing the fistula too low makes changing the prosthesis difficult • Cut down onto the tip of the artery forceps with a scalpel, and pass the tip of the forceps through the fistula into the tracheal lumen • Hold the tip of a 14-gauge Foley urinary catheter with the artery forceps and pull the catheter through the fistula into the oesophagus and pass it through the pharyngeal defect (Figure 29). Then advance the catheter down the oesophagus. Avoid accidental displacement of the catheter by injecting 5ml water into the bulb and by fixing the catheter to the skin with a suture • The catheter acts as a stent to allow the fistula to mature in preparation for fitting a tracheo-oesophageal prosthesis, and is initially used for stomagastric feeding • An alternative method is to insert a speech prosthesis ab initio, and to feed the patient via a nasogastric tube, or a catheter passed through the speech prosthesis (Postlaryngectomy vocal and pulmonary rehabilitation) • Divide the sternal heads of the sternomastoid muscles to create a flattened peristomal contour and to facilitate digital stomal occlusion (Figure 30). • At least 2.5cm transverse diameter of residual pharyngeal mucosa is required for primary pharyngeal closure. The teaching that the minimum pharynx required is that which may be closed over a nasogastric tube is incorrect, as the neopharynx is then too narrow for adequate swallowing and voicing • A horizontal/transverse closure is preferred as it maximises the capacity of the pharynx (Figures 31). Only if there is undue tension on the suture line, then do T-shaped closure, keeping the vertical limb as short as possible   (Figure 36)

Pharyngeal reconstruction
Following resection of large pyriform fossa tumours (Figure 37) or tumours that extend close the cricopharyngeus, or involve the postcricoid area, only a narrow strip of mucosa may remain to reconstruct the neopharynx. If the residual pharyngeal mucosa is <2.5cms in width, then additional tissue is required to avoid pharyngeal stenosis, dysphagia and poor speech (Figure 38). Reconstructive options include pectoralis major, latissimus dorsi and supraclavicular flaps, or microvascular free tissue transfer flaps (radial forearm, anterolateral thigh). All these flaps can be used to augment the pharyngeal repair, or when the pharynx has been completely resected, may be tubed to entirely replace the pharynx (Figures 39 -42).
Following pharyngeal reconstruction with a flap, a contrast swallow X-ray is done on about day 7 to exclude an anastomotic leak before commencing oral feeding.