Читать книгу The Esophagus - Группа авторов - Страница 163

In the United States, squamous cell carcinoma of the head and neck (tongue, pharynx, larynx) is five times more common than squamous cell carcinoma of the esophagus. More than 20% of patients with squamous cell carcinomas of the head and neck have synchronous or metachronous carcinomas of the oral cavity, pharynx, larynx, esophagus, or lungs [53]. About 90% of malignant tumors in the oropharynx and hypopharynx are non‐keratinizing squamous cell carcinomas. Almost all of these tumors are detected in moderate or heavy abusers of alcohol, tobacco, or both.

The signs, symptoms, prognosis, and treatment of pharyngeal cancer depend on the location of the tumor. Most patients have symptoms of short duration (less than four months), including sore throat, hoarseness, dysphagia, and odynophagia. The overall five‐year survival rate for these patients is 20–40% [52–54].

The radiographic findings of squamous cell carcinoma are those of any mucosal tumor in the gastrointestinal tract [55–58]. The normal contour of the involved structure is disrupted by a protrusion into the lumen or by an ulceration extending outside the expected luminal contour. Intraluminal tumor is manifested as an area of increased radio‐opacity replacing the normally air‐filled lumen or as a radiolucent filling defect in the barium pool [55] (Figure 6.26). The irregular mucosal surface of the tumor is manifested as a granular, nodular, ulcerated, or lobulated surface or as barium‐etched lines in an unexpected configuration or location [57] (Figure 6.26). The mobility or distensibility of the involved structure may be compromised (Figure 6.27).

The palatine tonsil is the most common site of involvement of squamous cell carcinoma of the pharynx. Tonsillar tumors can spread to the posterior pharyngeal wall, soft palate, and base of the tongue. Lymph node metastases are seen in about one‐half of these patients [52, 54]. Squamous cell carcinomas of the tongue base are usually advanced tumors that already have spread deep into the intrinsic or extrinsic muscles of the tongue [59] (Figure 6.26). These tumors can also invade the palatine tonsils, valleculae, or pharyngoepiglottic folds. Lymph node metastases are present in about 70% of cases at the time of presentation [52].

The supraglottic laryngeal structures (epiglottis, aryepiglottic folds, mucosa overlying the muscular process of the arytenoid cartilages, false vocal cords, and laryngeal ventricle) arise from pharyngobuccal anlage, forming a portion of the anterior wall of the hypopharynx [1]. Supraglottic cancers (Figures 6.27 and 6.28) are often classified as a subsite of “laryngeal” rather than pharyngeal tumors. These lesions frequently cause coughing and choking [60]. Hoarseness occurs in patients with supraglottic and laryngeal carcinomas as well as carcinomas of the medial piriform sinus infiltrating the arytenoid cartilage or cricoarytenoid joint [61]. The supraglottic region has an extensive lymphatic bed; supraglottic cancers therefore tend to spread throughout the supraglottic region and into the pre‐epiglottic space. Cervical lymphadenopathy is detected in one‐third to one‐half of these patients [52, 54].

Figure 6.17 Lateral pharyngeal pouches. (A) Line drawing of the pharynx in lateral view shows the area of weakness (arrow) that a lateral pharyngeal pouch protrudes through, bounded by the hyoid bone (b) superiorly, the posterior border of the thyrohyoid muscle (m) anteriorly, the superior cornu of the thyroid cartilage (c), and the insertion of the stylopharyngeal muscle (s) posteriorly. The ala of the thyroid cartilage (T) is identified.

Source: Reproduced from Rubesin et al. [2], with permission.

(B) Frontal view of the pharynx just as the bolus reaches the valleculae shows no evidence of lateral pharyngeal pouches. (C) Frontal view of the pharynx as the bolus passes through the pharyngoesophageal segment shows 1.5 cm and 1 cm barium‐filled sacs (arrows) on the left and right pharyngeal walls, respectively. The tilting epiglottis is identified (arrowhead).

Squamous cell carcinomas of the piriform sinuses are usually bulky masses that already have spread to lymph nodes in 70–80% of patients at the time of presentation [52] (Figure 6.29). Tumors of the medial piriform sinus wall may invade the ipsilateral aryepiglottic fold, arytenoid and cricoid cartilage, and paraglottic space, often resulting in hoarseness [61]. Tumors of the lateral piriform sinus wall may invade the thyroid cartilage, thyrohyoid membrane, and neck, including the carotid sheath [52].

Figure 6.18 Lateral pharyngeal diverticulum. A 0.8 cm barium‐filled sac (arrow) persists outside the left lateral wall of the pharynx after the bolus has passed.

Figure 6.19 Branchial pouch sinus. (A) Frontal view of the pharynx shows an 8 cm long track (arrows) that courses inferiorly from the floor of the mouth. (B) Steep right posterior oblique view of the pharynx demonstrates the track (arrows) arising from the retromolar trigone/anterior portion of the tonsillar fossa. Dentures are in place.

Source: Reproduced from Rubesin and Glick [23], with permission.

Squamous cell carcinomas of the posterior pharyngeal wall (Figure 6.30) are large, bulky tumors that cause few symptoms, often presenting as painless neck masses resulting from metastases to cervical lymph nodes [62]. More than half of these patients have lymph node metastases at the time of diagnosis. These exophytic tumors may spread superiorly or inferiorly into the nasopharynx or cervical esophagus and posteriorly into the retropharyngeal space. These tumors are the pharyngeal cancers most frequently associated with a synchronous or metachronous squamous cell carcinoma of the oral cavity, pharynx, or esophagus [62].

Postcricoid carcinomas (Figure 6.31) are an uncommon form of pharyngeal squamous cell carcinoma, except in Scandinavia. These tumors may also spread superiorly or inferiorly into the hypopharynx or cervical esophagus.

Figure 6.20 Candida pharyngitis. Innumerable nodules and plaque‐like elevations have disrupted the normally smooth surface of the pharynx.