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around the ap and secured to the prevertebral fascia to create a two-layer closure
of the pharynx [51]. Because of its greater size and bulk, the ALT also serves as a
good option when total glossectomy is performed with laryngopharyngectomy as it
can ll the oor of mouth defect and close the pharyngeal defect with a single paddle.
The ALT free ap is favored by many surgeons for pharyngeal reconstruction
due to the additional exibility afforded by the ap to perform multilayered reconstruction using fascia and muscle, which is not possible with other aps. Yu etal.
described a series of patients constructed using a multilayered closure with the ALT
for both partial and circumferential defects using fascia to reinforce suture lines
with a stula rate of 9%, including 10% among patients in the salvage setting [51].
Similarly, Chen etal. found that closure utilizing multilayer closure with fascial
underlay signicantly decreased rates of PCF (3% vs. 20%) when compared to
single- layer closure.
Because most studies comparing the impact of reconstructive techniques were
small, underpowered retrospective series, larger multicenter studies were designed
to further elucidate the efcacy of various reconstructive modalities in preventing
PCF. Patel et al. described a multicenter retrospective study of 359 patients and
found that the rate of PCF was highest in the primary closure cohort (34%) [69].
There were lower rates of stula with pectoralis muscle onlay ap (15%) than with
free ap (25%), though this difference was not statistically signicant. Of note, the
majority of free aps performed in this cohort were RFFF, which may have contributed to the higher rate of PCF. In 2019, the Microvascular Committee of the
American Academy of Otolaryngology-Head & Neck Surgery published a separate
large, multicenter retrospective review of 486 patients who underwent salvage laryngectomy or laryngopharyngectomy [69]. As with the Patel study, this study demonstrated signicant reduction in the rate of PCF with vascularized tissue compared
to primary closure, although it did not nd any signicant difference in the rate of
stula among reconstructions with or without augmentation with muscle. Ultimately,
these large retrospective studies were unable to distinctly identify a superior reconstructive approach, though both clearly demonstrated the importance of vascularized tissue augmentation compared to primary closure alone in the post-radiation
setting.
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Enteric Conduit Options
forPharyngoesophageal Replacement
Gastric Conduit
Enteric conduits are generally utilized in the setting of pharyngectomies requiring
concurrent esophagectomy beyond the cervical esophagus. In these deformities,
either the length of required soft tissue replacement is too long for regional ap or
MVFTT reconstruction (e.g., deformity of the pharynx to the stomach in total
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R. Y. Wang et al.
esophagectomy) or the reconstructive suture line is intrathoracic, precluding a safe
soft tissue anastomosis as any breakdown could lead to mediastinitis. While there
are several enteric donor tissues for pharygnoesophageal reconstruction, the tubularized gastric conduit is considered the preferred method for esophageal replacement given its ease of construction and requirement of only a single pharyngeal
anastomosis (Fig.8.7), [84, 85]. The stomach is a well-vascularized organ, which is
supplied by the left gastric artery that arises from the celiac axis, the right gastric
artery that arises from the proper hepatic artery, the left gastroepiploic artery arising
from the splenic artery, the right gastroepiploic artery arising from the gastroduodenal artery, and short gastric vessels arising from the distal splenic artery [86]. For a
tubularized gastric conduit, the vascular supply is exclusively the right gastroepiploic artery [87]. Consequently, this vessel must be identied and preserved at all
costs during conduit construction and intraoperative factors associated with hypoperfusion should be mitigated.
Preoperatively, because anastomotic complications are a signicant source of
morbidity after pharyngoesophectomy, it is prudent to optimize medical comorbidities associated with such complications, including cigarette use, malnutrition, obesity, chronic obstructive pulmonary disease, corticosteroid use, renal insufciency,
hypertension, and heart failure preoperatively [88–91].
Following transthoracic mobilization of the esophagus and mediastinal lymphadenectomy, the operation proceeds with transabdominal construction of the conduit, which can be performed via a traditional “open” approach or minimally
invasive techniques. During the gastric mobilization, a strict “no touch” technique
should be used to minimize trauma to the microvascular blood supply of the eventual gastric conduit. Conduit preparation is begun by taking down the gastrohepatic
Fig. 8.7 Gastric pull up reconstruction of total laryngopharyngectomy and esophagectomy defect
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ligament and continuing to the base of the right crus. The left gastric artery and vein
are skeletonized and divided. At the greater curvature, after identifying the course
of the right gastroepiploic artery, the greater omentum is separated from the transverse mesocolon, and the short gastric vessels are taken down all of the way to the
angle of His. Any remaining retrogastric attachments are also taken down. Because
the stomach is tethered by the hilum of the liver rather than the lateral attachments
of the duodenum, a former Kocher maneuver has little value. However, it is important to take down all retrogastric and antropyloric attachments, and, for those
patients who have undergone cholecystectomy, adhesions to the gallbladder fossa,
as these can impair mobility of the gastric conduit. The esophagus is circumferentially mobilized into the mediastinum until the transabdominal dissection plane
communicates with the transthoracic dissection plane. During the thoracic phase of
the operation, the distal esophagus is looped with a Penrose drain to assure that
esophagus has been fully mobilized. If desired, a gastric emptying procedure and
feeding jejunostomy tube may be placed.
Though anastomotic complications are similar, because of its greater reach,
(likely) improved conduit emptying, and superior functional outcomes, a gastric
tube is preferred over the whole stomach as a gastric conduit [92]. Because of the
location of microvascular anastomotic branches between the left gastric and right
gastroepiploic vessels, the preferred width of the conduit is approximately 4cm
[87]. While preserving one to two branches of the right gastric artery along the
lesser curve, conduit construction begins with a linear stapler approximately 5cm
cephalad to the pylorus and continues along a line parallel to the greater curvature.
A key technical maneuver is to provide simultaneous cephalad (at the apex of the
fundus) and caudal retraction (on the body of the stomach), in order to create a long,
straight conduit, without spiraling.
Anastomotic complications are a signicant source of morbidity and mortality
after pharyngoesophagectomy. A meta-analysis of mainly retrospective reviews and
case series of laryngopharyngectomies followed by gastric pull up from 1990 to
2014 found the risk of anastomotic leak to range from 0 to 23% [85]. Most were
successfully treated with nonoperative management including NPO status, nutritional support, antibiotics, and drainage. For larger leaks, soft tissue coverage over
a salivary bypass tube may be required [93]. Gastric conduit necrosis, which is a
feared complication, has been reported in up to 5% of patients, is a signicant risk
for perioperative mortality, and may require resection and diversion if there is signicant conduit loss [94]. As a consequence of ischemia, tension, and healed leaks,
anastomotic strictures occur in approximately 5–10% of patients; dilatation is the
primary method of treatment [95].
Given the signicant source of morbidity and mortality associated with anastomotic complications, investigators have explored methods to mitigate this risk.
Several have investigated gastric ischemic preconditioning by embolization of, or
laparoscopic ligation of, the left gastric artery typically at least a week before esophagectomy. However, strong evidence supporting this technique is lacking, and it has
not gained widespread acceptance [96]. However, there are certain populations (yet
to be claried) where preconditioning may have specic value, such as current or
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recent smokers. To improve blood ow to the tip of the gastric tube, others have
explored the use of a supercharged anastomoses to the transverse cervical artery and
to the external jugular vein, anterior jugular vein, or internal jugular vein [97].
Further studies are needed to determine when microvascular anastomoses have
added value.
An alternative to the standard isoperistaltic gastric tube is a reversed gastric tube
based on the left gastroepiploic pedicle. It has the advantages of greater length compared with an isoperistaltic gastric tube and, like an isoperistatic tube, only requires
a single anastomosis. Its long staple line and tenuous blood supply are distinct disadvantages. To enhance blood ow, investigators have explored use of a supercharged graft with promising results [98]. However, this technique has not gained
widespread acceptance, and an isoperistatic tube remains the rst conduit of choice.
R. Y. Wang et al.
Colonic Interposition
Despite the stomach being the most popular choice for esophageal replacement, the
colon has reliably been used as a conduit since the early 1900s [99]. The stomach
may not be a suitable conduit either because it does not have the appropriate length,
there is prior gastric surgery such as weight loss operations, or underlying gastric
pathology. The colon interposition is an appropriate alternative conduit that can reliably reach the pharynx. It has advantages of its length, resistance to bile and acid
reux, and its robust vascular supply [100]. The colon is also a good option in cases
of surgical salvage of a failed gastric conduit. Careful preoperative evaluation of the
entire colon is needed to determine if the colon is a suitable replacement option.
A CT scan with arterial enhancement is helpful for assessing the colonic vasculature or colonic pathology. Patients with underlying cardiovascular disease may
have calcication or stenosis of the superior and inferior mesenteric arteries and the
colic vessels and may inuence whether a left or right interposition or alternative
conduit is used [101]. To exclude underlying pathology, all patients 45years of age
and older, younger patients with known colon pathology, and those with a family
history of colon cancer should have a colonoscopy within the proceeding 5years.
The blood supply for an ascending colon graft originates off the superior mesenteric artery (SMA) and the ileocolic artery, whereas the blood supply for a descending colon graft originates from the inferior mesenteric artery (IMA) and the
ascending branch of the left colic. In addition, the Marginal Artery of Drummond
forms a variable and important anastomotic connection between the SMA and IMA
[101]. The right colon has a more variable vascular anatomy. As a result, the
descending colon graft is generally preferred for most patients. It is also important
to note that anatomic variations of the middle colic artery include complete absence
in up to 25% of patients with presence of an accessory middle colic artery in
10% [102].
During graft harvest, the colon should be fully mobilized off its peritoneal and
retroperitoneal attachments to allow splaying of its mesentery and assessment of the
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vascular arcades. Transillumination is done to identify the blood supply. Prior to
vascular division, the vessels are temporarily clamped, and a handheld Doppler is
used to assure adequate ow to the tip of the planned conduit and to the colocolostomy. It is important to preserve the distal vascular arcades during the mesenteric
dissection. Both left and right interpositions are typically prepared in an isoperistaltic fashion, which has been shown to improve functional outcomes and minimize
the risk of spasms [103, 104]. There is typically ample length to perform a handsewn anastomosis to as high as the base of the tongue. If the anastomosis is under
tension, additional length can be achieved by further dividing the mesentery while
preserving the blood supply to the graft, although most colonic conduits can reach
the pharynx without additional lengthening maneuvers [105]. In the rare instance
that the arterial ow or the venous drainage of the tip of the conduit is impaired, a
supercharged microvascular arterial and/or venous anastomosis can be performed
(Fig.8.8), [106, 107].
It is preferable to construct the distal anastomosis of the colon interposition to
the stomach, even if the amount of stomach remaining is limited. When a total gastrectomy has been performed, anecdotally, colon interpositions function better
when the anastomosis is constructed on the duodenum rather than a roux limb of
jejunum. A key technical point of all esophageal replacement grafts is for the graft
to lie as straight as possible in order to facilitate conduit emptying and thus improve
functional outcomes. Conduit emptying is mainly passive relying on gravity.
Redundancy of the conduit can lead to dysphagia and aspiration [103]. After gently
pulling down the redundancy in the graft from the abdomen, it is recommended to
tack the interposition graft to the hiatus to minimize tension with permanent
braided suture.
Though colon interposition has been a reliable conduit for esophageal replacement after pharyngoesophagectomy, it has a longer operative time and requires
Fig. 8.8 Supercharged
colon interposition graft
reconstruction of a total
esophagectomy defect
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more (three rather than one) anastomoses as compared with the gastric pull up
[108]. Postoperative mortality has been reported to be as high as 5–17% but is typically less than 5% in high volume centers [109–111]. Published anastomotic leak
rates vary widely from 0 to 50%, but larger studies from high volume centers suggest a rate of approximately 10%. Graft necrosis represents the most serious surgical complication, occurring in less than 2.4% of patients in experienced centers but
is the most common cause of reoperation and a signicant cause of mortality
[112, 113].
Functional outcomes after colon interposition are excellent and may be better
than a gastric conduit due to a lower risk of reux and dysphagia [114]. The majority of patients (75–100%) after colon interposition are able to resume oral intake,
and more than half resume a normal diet. In one prospective study looking at the
long-term functional outcomes in a selected group of long-term survivors who
underwent colonic interposition, 89% of patient reported no dysphagia, 84%
reported no regurgitation or reux, and 91% were able to consume three or more
meals daily [115]. Quality of life metrics 21months and 10years after interposition
were at normal values. Of note, 11% had required surgical revision for symptoms
related to redundancy, highlighting the importance of minimizing this technical
complication during the index operation.
R. Y. Wang et al.
Supercharged Jejunal Interposition
Another alternative to a tubularized gastric conduit is a pedicled jejunal graft and a
microvascular (“supercharged”) anastomosis. The jejunum has been used for
decades as a conduit, and supercharging allows for a generous length of jejunum to
be utilized for high neck anastomoses [116]. As compared with a colon interposition
graft, advantages of a supercharged jejunal conduit are its more reliable vascular
supply. It also offers a similar size to the native esophagus, is generally free of
intrinsic disease, is less prone to redundancy, and maintains peristalsis, which may
improve functional outcomes [117]. However, it tends to be more at risk for marginal ulceration and requires a trained microvascular surgeon to construct the supercharged microvascular anastomosis, which increases the operative time [118].
Harvest of a supercharged jejunal conduit starts with identifying a segment of
jejunum 20cm to 30cm from the ligament of Treitz. The vascular supply should be
carefully assessed. The rst jejunal branch off the SMA is preserved while the second branch is divided and clamped and used for the eventual microanastomosis. The
third branch can be ligated to allow for appropriate length, and the fourth branch
should be preserved to its SMA supply [119]. Like other conduit options, transillumination and Doppler ultrasonography is important to assure an intact vascular
arcade. Once fully mobilized, the conduit should be exteriorized and brought to the
desired location at the neck to determine if there is adequate length for a tensionfree anastomosis. If there is not adequate length, one option is to divide some of the
mesentery between the jejunal branches while preserving the arcades. An indicator
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ap is fashioned by dividing a short segment of the most superior portion of the
jejunum (but remains connected to the mesentery). Typically, a left partial rst rib
resection and hemimanubriectomy with resection of the head of the clavicle is performed at the neck to allow space for the conduit and its mesentery. Arterial and
venous microvascular anastomoses from the second jejunal branch to the chest
(internal mammary artery) or neck (most commonly the transverse cervical artery)
are performed. The end-to-end pharyngo-jejunal anastomosis is typically handsewn. The distal end of the jejunum is then anastomosed to the posterior stomach,
or it can be connected in a Roux-en-Y formation [120].
Several small studies have looked at outcomes following supercharged jejunal
interposition and found low rates of mortality, anastomotic leak, and graft loss. The
largest series (60 patients) noted a 30-day mortality of 5% [118]. The anastomotic
leak rate was 32%. However, half of those leaks were of minimal clinical signicance, identied by contrast study alone and were managed with simple drainage.
Conduit loss was reported in 8.3% of cases contributing to the majority of the 31%
of reoperations. In this series, functional outcomes were favorable with 83% able to
return to an oral diet. Interestingly, postoperative manometry of some of these
patients with successful reconstruction revealed intact jejunal peristalsis, which is
thought to aid in passage of food boluses. However, in those undergoing total larnygopharyngectomy and tracheoesophageal puncture, peristalsis may interfere with
speech production. Long-term functional outcome were good with 80% of patients
having no dysphagia and 78% able to maintain a total oral diet for nutrition [121].
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Route ofConduit
Enteric conduits can be passed from the abdomen to the neck via one of four routes.
The most common and preferred route is the posterior mediastinal position or the
orthotopic esophageal location. This provides the shortest path and forms the most
natural lie for a gastric, colon or jejunal conduit [122]. However, in cases where the
posterior mediastinum is hostile (i.e., after esophageal exclusion), an alternative
route is needed.
The substernal route is the most common option when the posterior mediastinum is not available. The conduit sits between the sternum and the anterior pericardium. Typically, the graft can be tunneled in the substernal space without performing
a full sternotomy. Care must be taken for patients who have had a prior median
sternotomy, especially those that have undergone coronary artery bypass grafting
due to the risk of iatrogenic injury during sternal re-entry [123]. Typically, performance of a left hemimanubriectomy and resection of the left sternoclavicular joint
to avoid impingement on the conduit should be performed.
A large Japanese retrospective analysis of gastric conduits undergoing retrosternal versus posterior mediastinal review found a lower leak rate 11.7% versus 13.8%
in the posterior mediastinal group but a higher rate of surgical site infection (14.9%
vs. 8.4%). In addition, the risk of pneumonias were higher in the posterior
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mediastinal route (13.7% vs. 12.2%) [124, 125]. No difference in morbidity was
seen. Other studies have also demonstrated an increased leak rate when using the
substernal route.
The intra-pleural route, which involves passage of the conduit through the left
pleural space anterior or posterior to the pulmonary hilum, is a rarely used alternative to a substernal pull up that requires a longer length of conduit as compared with
the posterior mediastinum or substernal route [124]. A subcutaneous route is also
seldom used, but when other spaces are not available, a subcutaneous tunnel above
the sternum with the conduit exiting the abdomen via a subxyphoid ventral hernia
can be created and connected to the subcutaneous neck where the pharyngeal anastomosis is performed. The conduit again will require a longer length and comes with
a poorer cosmetic outcome.
R. Y. Wang et al.
Postoperative Considerations
Voice Rehabilitation
Loss of the ability to phonate is a debilitating consequence of total laryngectomy.
Since early attempts to develop an articial larynx for phonation in the late nineteenth century, numerous advances have been made in vocal rehabilitation after
laryngectomy in both available prostheses and devices, and in techniques that can
be utilized to optimize communication [126]. Today, the primary modalities utilized
by patients for phonation are the electrolarynx, tracheoesophageal (TE) speech, and
esophageal speech. Understanding of these options is important for the reconstructive surgeon as the techniques used in pharyngeal reconstruction can impact patients’
ability to communicate postoperatively.
Electrolarynx
Replacing older mechanical devices, the electrolarynx is a battery-powered device
that vibrates the tissues of the oral cavity and pharynx to produce speech either
through direct contact in the neck or a plastic tube that is placed in the oral cavity.
Because it is easy to use and can be utilized by virtually all patients who have undergone laryngectomy, the electrolarynx is often the rst option offered to patients after
surgery. Further, it does not preclude use of esophageal or tracheoesophageal (TE)
speech and serves as a useful backup. Although some patients may be unable to use
the device directly on the neck if there is excessively thick tissue, most are typically
able to use it intraorally. Despite its versatility, the electrolarynx does have some
drawbacks. While newer models do allow pitch modulation to allow for more
natural- sounding speech, the electrolarynx has a mechanical sound quality and
allows limited intonation due to its xed fundamental frequency which may limit
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intelligibility. As with other forms of alaryngeal speech, a fair amount of time and
practice is required to achieve maximum intelligibility. Most models also require
the user to hold the device during phonation, although some newer devices have
hands-free functionality. While the electrolarynx is typically readily available to
patients in the United States, access may be more difcult in other settings.
Nonetheless, the electrolarynx is an excellent option for most patients and with
proper training can serve as an effective means of verbal communication after
laryngectomy.
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Esophageal Speech
Because it relies on the vibration of the patient’s pharyngoesophageal tissues to
generate sound and does not require any additional prostheses or equipment, esophageal speech is the oldest form of alaryngeal speech. With esophageal speech, air is
ingested and forcefully passed back through the pharyngoesophageal segment, generating vibrations which serve as the foundation of the voice. Unlike with the electrolarynx, the voice quality with esophageal speech more closely approximates that
of normal laryngeal speech [127]. Furthermore, it does not require the user to use
any prostheses or devices, allowing for hands-free speech. While esophageal speech
only relies on the patient’s normal remaining anatomy for generation of voice, it
requires a signicant amount of training and expertise to generate reliable speech.
Even with practice, speech intelligibility tends to be inferior to that with TE speech
and is limited in duration due to the need to expel air from the gastrointestinal tract
rather the lungs. Esophageal speech is a good option in motivated patients who are
unwilling or unable to undergo tracheoesophageal puncture (TEP) and have access
to speech pathologists who are knowledgeable with the technique.
Tracheoesophageal Puncture (TEP)
In the appropriate patient, TE speech is the gold standard in alaryngeal speech as it
produces a voice more similar to native laryngeal speech than either the electrolarynx or esophageal speech. TE speech allows for greater clarity, maximum intensity,
and phonatory duration than esophageal speech and a much more natural quality
than electrolarynx. These advantages allow TE speakers to enjoy improved voicerelated quality of life than those using either electrolarynx or esophageal
speech [128].
To facilitate TE speech, a tracheoesophageal puncture is performed, generating a
controlled stula between the trachea and the neopharynx or esophagus through
which a prosthesis with a one-way valve is placed. This valve allows for direction
of air into the pharyngoesophageal segment with occlusion of the tracheostoma
while preventing aspiration of food or secretions. TEP can be performed primarily
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at the time of laryngectomy or at a later time. There is concern regarding the risk of
postoperative complications with primary TEP as a prior analysis of the National
Surgical Quality Improvement Program (NSQIP) database demonstrated increased
overall wound complication rate, though the rates of surgical site infection and
return to the operating room did not differ [129]. Patients requiring complex reconstruction with MVFTT or bowel transposition may not be candidates for primary
TEP, though some of these patients may be eligible after sufcient time has passed
for wound healing. It is the author’s preference to wait at least 3months after reconstruction before placing TEP.A retrospective series by Gitomer etal. found that in
patients undergoing MVFTT for pharyngeal reconstruction, those undergoing secondary TEP had higher utilization rates that those who underwent primary TEP
[130]. The method of reconstruction of the pharynx may also affect speech outcomes, as patients with muscle augmentation—primarily from the pectoralis aps—
have been shown to have worse speech and swallowing outcomes [52].
While TE speech is an excellent modality for voice rehabilitation after laryngotomy, a high level of cognitive function and dexterity is required to use and maintain the prosthesis. Furthermore, most patients will require exchange of their
prosthesis at least a few times a year if not more frequently, adding greater complexity and expense to their care [131]. While surgical complications from the TEP are
uncommon, issues that interfere with patients’ ability to produce TE speech are
more common [131]. These can include spasms or stenosis of the pharynx, stenosis
of the stoma, prosthesis malfunction, and enlargement of the TEP site. The latter
complication may be particularly problematic as leakage through the TEP can result
in increased risk of pneumonia [132]. Enlarging TEP sites can usually be managed
with conservative measures such as placement of larger prostheses, though a small
proportion of patients will require closure of the stula [132]. These defects often
arise in radiated patients and can be challenging to manage due to the need for
robust tissue to repair the defect without excessive bulk, which would obstruct the
pharynx or tracheostoma; techniques using folded or double-paddled forearm free
aps have been described to manage these complex defects [70, 133].
R. Y. Wang et al.
Swallowing Outcomes
Patients with advanced laryngeal and pharyngeal cancers often suffer from signicant dysphagia, which results from either their malignancy or adverse effects from
treatment. For example, subsequent analysis of RTOG 91-11—which excluded
patients with very advanced T4 disease—demonstrated that 27% of patients were
gastrostomy dependent prior to treatment due to severe laryngeal dysfunction [134].
Patients undergoing concurrent chemoradiation suffer high rates of severe toxicity;
77% of patients in the concurrent chemoradiation arm of RTOG 91-11 suffered
from grade 3 or 4 adverse effects during treatment with 35% experience severe
pharyngeal or esophageal toxicity [4]. Retrospective analysis of functional outcomes following concurrent chemoradiation in RTOG 91-11, 97-03, and 99-14
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