The hypopharynx and supraglottic larynx are unique parts of the upper aerodigestive tract. These sites are critical to the functions of airway, speech, and swallowing. Therefore malignancy at these sites requires careful assessment and consideration of treatment options.
Controversy reigns as to the optimal treatment option for early cancers of the hypopharynx and larynx. Although more than 90% of these malignancies are squamous cell carcinomas, there is a variation in the behavior and treatment response of cancers at these sites within this histological diagnosis. Cancers at these sites may be exophytic and demonstrate good response to either radiation or partial laryngeal and pharyngeal resection. However, some early cancers may be deeply infiltrating and, in patients with a significant history of cigarette smoking and alcohol consumption, single modality treatment may not be sufficient to provide enduring locoregional control and cure. Furthermore, hypopharyngeal cancers may have submucosal spread of disease, which can extend one to three centimeters from the primary site, and this needs to be factored into consideration when designing resection and or radiation margins. Patients’ professional and social demands further compound the factors that need to be considered when making treatment decisions.
The response to radiation of early cancers and the lack of experience with, and the poor swallowing outcomes associated with, previous external partial laryngeal surgery, often directed clinicians to offer treatment with nonsurgical protocols. Although these cancers are radiosensitive, because of the high rate of nodal metastases, radiation requires a wide field of radiation, including both necks. Surgical options with minimal morbidity to speech, swallowing, and the airway provide an opportunity to avoid the early and late toxicities associated with radiation and chemoradiation protocols. This is particularly important as an option for the younger patient, who prioritizes early return to employment, social and family responsibilities, and avoidance of the late toxicities of chemoradiation protocols.
The advent of transoral LASER and transoral robotic surgery (TORS) has provided an option of minimally invasive organ preservation surgery. There is evidence in the literature of equivalent or better swallowing and speech outcomes for suitably identified and accessible cancers, when performed by trained surgeons in high volume surgical centers.
Assess relationships to
Major vessels and their branches
Adjoining lymph nodes
Adjacent structures (e.g., thyroid and cricoid cartilages and hyoid bone)
Examination under anesthesia
Assess access to resection with clear margins
Assess tumor mobility from deeper structures and involved lymph nodes
Surgical steps for hypopharyngeal tumors
Anesthesia—orotracheal intubation for lateral lesions, nasotracheal for anterior lesions
Circumferential mucosal incision around the tumor
Develop deep margins of excision down to thyroid and arytenoid cartilages
Surgical steps for supraglottic tumors
Compartmental resection of supraglottic larynx
Anesthesia—Nasotracheal intubation for most lesions and usually extubated 24 hours later
Mucosal incision dividing aryepiglottic fold
Develop lateral plane down to inner lamina of thyroid cartilage
Extend this plane anteriorly toward petiole of epiglottis above anterior commissure
Mucosal incision of contralateral aryepiglottic fold and similar incision and dissection to join the first dissection in plane of inner lamina of thyroid cartilage
Lateral mucosal incisions across vallecula and tongue base
Develop deep plane through tongue muscle and connective tissue of preepiglottic space
Beware of vascular branches of lingual and superior thyroid arteries
Anterior mucosal incision through tongue base mucosa
Develop plane through tongue base muscle insertion into hyoid bone
Observe “silver glistening” when electrosurgical energy strikes hyoid bone
Develop deep plane of dissection posterior to periosteum of hyoid bone and contiguous with perichondrium of thyroid cartilage
Connect plane of dissection with original inferior incisions through aryepiglottic folds, leaving true vocal cords behind
Key specific issues
Use clip applicators, bipolar diathermy supplement with topical agents (Surgiflo/Floseal/Purastat) and systemic tranexamic acid
Da Vinci robot (made of patient side cart, surgeons console, vision cart +/− training cart)
Secondary video tower, in adequate position for surgical assistant at patient bedside
Feyh-Kastenbauer (FK) or Feyh-Kastenbauer-Weinstein-O’Malley modification (FKWO)
Medrobotics Flex Retractor System
Camera 0-degree and 30-degree (30-degree to access tongue base and larynx)
Microlaryngoscopy instruments that must include vascular clip applicators and clips
Robotics instruments including Endowrist monopolar cautery spatula, with an Endowrist, Maryland, or Endowrist fenestrated bipolar robotic forceps
Bayonet bipolar cautery
Headlight for surgical assistant at patient bedside
Photographic transparent cheek retractor
Thermoplastic nasal splint (used for dental guard/protection)
Tonsillectomy pillar retractor
Two Yankauer (pediatric) suckers
Anatomy of the supraglottic larynx and hypopharynx
The larynx and hypopharynx are intimately associated and share anatomical boundaries. The pharynx can be considered as a three-walled structure which opens anteriorly to an air containing space. The pharynx is divided into the nasopharynx, the oropharynx. and the hypopharynx. The nasopharynx has a posterior wall upon which lies the adenoid tissue, and its two lateral walls contain the nasopharyngeal openings of the eustachian tubes. The nasopharynx opens anteriorly to the air containing posterior choanae of the nose. The oropharynx extends from the level of the soft palate to the level of the vallecula. It has a posterior pharyngeal wall that contains lymphoid tissue, and these are sometimes prominent laterally as the lateral pharyngeal bands. The lateral walls of the oropharynx contain the palatine tonsils and opens anteriorly to the airspace of the oral cavity.
The hypopharynx is the longest segment of the pharynx, extending widely above from the vallecula at the level of the hyoid and narrowing down toward the post cricoid ring leading into the esophagus at the level of the cricoid. The hypopharynx opens anteriorly to the air containing larynx.
It has a distinct posterior wall and expands laterally into the pyriform sinuses. These lateral expansions have an intimate relationship with the larynx. The medial wall of the hypopharynx is a lateral relation of the posterior larynx ( Fig. 44.1 ). It is important to recognize that the lateral wall of the hypopharynx near its apex occupies and lies medial to the posterior third of the thyroid cartilage. The division of the hypopharynx into theses subsites is important in determining the stage of the cancer and when planning resection of hypopharyngeal cancers ( Fig. 44.2 ). Cancers limited to one subsite are ideal candidates for transoral resection.
The critical subsite is the postcricoid region of the hypopharynx which is a complete ring leading into the esophagus (see Fig. 44.2 ). Cancers involving this region require a total laryngopharyngectomy and reconstruction of a neopharynx with a tubed free vascularized flap (e.g., Radial Forearm flap or Antero-Lateral Thigh flap) or a pedicled regional flap (e.g., pectoralis major myocutaneous flap) or a vascularized tube such as a free jejunal flap.
The larynx is divided into three sections: the supraglottis, the glottis, and the subglottis.
The supraglottic larynx extends from above, along the free edge of the epiglottis and aryepiglottic folds and the arytenoid cartilages to a horizontal plane that extends through the midpoint of each laryngeal ventricle. The external skeleton of the supraglottic larynx is the hyoid bone, the thyrohyoid membrane, and the thyroid cartilage ( Fig. 44.3 ). Lying between the mucosa covering the supraglottic larynx and the external contour of the larynx is a “horseshoe-shaped” space filled with fat, lymphatic capillaries, and a rich vascular capillary network, known as the preepiglottic space. This midline preepiglottic space is in continuity with the paraglottic space on each side, lying between the vocal ligament and the thyroid cartilage. The supraglottic larynx and the pharynx are both embryologically derived from the fourth branchial arch; their lymphatic drainage is similar, with the primary drainage nodes being in levels II and III.
Supraglottic squamous cell carcinomas are often exophytic. They have a high incidence of ipsilateral and bilateral, occult or symptomatic cervical lymph node involvement. The risk of local regional neck nodal metastasis is about 60% for ipsilateral nodal disease, 25% for contralateral, and 30% for occult nodal involvement.
Early cancers and benign tumors of the supraglottic larynx and hypopharynx can be addressed surgically. Unfortunately, cancers of the hypopharynx and supraglottic larynx present late because patients are often asymptomatic or have vague symptoms. Poorly localized chronic sore throat, foreign body sensation in the throat, and referred otalgia are common early complaints. These regions are also not easy to examine by general medical practitioners. Advanced cases present with dysphagia and laryngeal symptoms or with a cervical nodal metastasis.
Cancers of the hypopharynx are not common and account for approximately 7% of all cancers of the upper aerodigestive tract. These cancers have a poor prognosis. They have a high rate of metastases, with nodal involvement present in 50% to 70% of cases at presentation. Cervical lymph node metastases occur as the presenting symptom in approximately 50% of cases and only 2% present as T1 lesions.
They are often poorly differentiated and have a high incidence of regional metastasis of about 60% for early lesions and 80% for advanced lesions. Hypopharyngeal cancers can exhibit submucosal spread and this can extend from 1 to 3 cm. The frequency of distant metastases is also among the highest of all head and neck cancers.
These cancers are associated with cigarette smoking and alcohol consumption. Women have a higher incidence of postcricoid cancers related to nutritional deficiencies (Plummer-Vinson syndrome). The 5-year survival rate with small (T1–T2) lesions is about 60% but, with T3–T4 lesions or multiple node involvement, survival falls to 17% to 32%. Five-year survival for all stages is approximately 30%.
Stages of supraglottic laryngeal cancer
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