{"id":13819,"date":"2026-03-11T22:55:43","date_gmt":"2026-03-12T01:55:43","guid":{"rendered":"https:\/\/rtmedical.com.br\/tmp-en-1773280540848\/"},"modified":"2026-04-04T18:06:13","modified_gmt":"2026-04-04T21:06:13","slug":"hypopharyngeal-carcinoma-delineation","status":"publish","type":"post","link":"https:\/\/rtmedical.com.br\/en\/hypopharyngeal-carcinoma-delineation\/","title":{"rendered":"Hypopharyngeal Carcinoma: Target Delineation"},"content":{"rendered":"<h2>Hypopharyngeal Anatomy and Patterns of Spread<\/h2>\n<p>The hypopharynx sits between the oropharynx superiorly and the cervical esophagus inferiorly. Its boundaries extend from the top of the hyoid bone \u2014 approximately at the C4 level \u2014 to the bottom of the cricoid cartilage, around C6, with the larynx lying anteromedially. Tumors here frequently disrupt both speech and swallowing, making functional preservation a central concern in treatment planning.<\/p>\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" class=\"alignright lazyload\" data-src=\"https:\/\/rtmedical.com.br\/wp-content\/uploads\/2026\/04\/hypopharyngeal-endoscopy-pyriform-sinus-mass.jpeg\" alt=\"Fiberoptic endoscopy showing mass effacing the pyriform sinus and left aryepiglottic fold in hypopharyngeal carcinoma\" src=\"data:image\/svg+xml;base64,PHN2ZyB3aWR0aD0iMSIgaGVpZ2h0PSIxIiB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciPjwvc3ZnPg==\" style=\"--smush-placeholder-width: 377px; --smush-placeholder-aspect-ratio: 377\/224;\"><figcaption>Fonte: Target Volume Delineation and Field Setup, 2nd Edition \u2014 Endoscopy of pyriform sinus mass with aryepiglottic fold involvement<\/figcaption><\/figure>\n<p>Three subsites define the hypopharynx: the paired pyriform sinuses, the posterior pharyngeal wall, and the post-cricoid region. Submucosal spread is perhaps the most challenging feature of this location \u2014 minimal barriers between anatomic sites allow tumors to involve multiple regions, the larynx, and adjacent soft tissue simultaneously. In clinical practice, the actual extent of disease often exceeds what the endoscopic exam reveals.<\/p>\n<p>Pyriform sinuses account for 65\u201385% of hypopharyngeal cancers. Each pyriform sinus is a potential space lateral and posterior to the larynx, with the medial wall formed by the aryepiglottic fold. The widest and most endoscopically accessible portion sits superiorly, while the space narrows inferiorly to the apex at the cricoarytenoid joint, forming an inverted cone. Pyriform sinus tumors may spread anteromedially to the arytenoids, aryepiglottic folds, and intrinsic laryngeal muscles \u2014 causing vocal cord fixation \u2014 as well as laterally into the paraglottic space and thyroid cartilage.<\/p>\n<p>The posterior pharyngeal wall accounts for approximately 10% of cases. It is a continuation of the lateral and posterior pharyngeal wall between the oropharynx and cervical esophagus, composed of mucosa enclosing the constrictor muscles. The post-cricoid region contributes less than 5% and may exhibit skip metastases to the cervical esophagus.<\/p>\n<h3>Patterns of Spread by Hypopharyngeal Subsite<\/h3>\n<table>\n<thead>\n<tr>\n<th>Subsite<\/th>\n<th>Direction of Spread<\/th>\n<th>Lymph Nodes at Risk<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td><strong>Pyriform sinus<\/strong><\/td>\n<td>Anteromedial: arytenoids, aryepiglottic folds, intrinsic laryngeal muscles (vocal cord fixation), paraglottic space<br \/>Posterior: constrictor muscles, prevertebral tissue<br \/>Lateral: paraglottic space, thyroid cartilage, lateral neck<br \/>Superior: oropharynx, pre-epiglottic space, thyrohyoid membrane (referred otalgia from internal branch of superior laryngeal nerve)<br \/>Inferior: post-cricoid area<\/td>\n<td>RP, II, III (most common); IV and VI (inferior tumors involving the apex)<\/td>\n<\/tr>\n<tr>\n<td><strong>Posterior pharyngeal wall<\/strong><\/td>\n<td>Superior: extension to oropharynx<br \/>Inferior: cervical esophagus<br \/>Posterior: prevertebral fascia, retropharyngeal space<\/td>\n<td>RP, II\u2013IV<\/td>\n<\/tr>\n<tr>\n<td><strong>Post-cricoid region<\/strong><\/td>\n<td>Anterior: laryngeal invasion (vocal cord fixation)<br \/>Superior: pyriform sinuses<br \/>Inferior: cricoid cartilage, cervical esophagus<\/td>\n<td>II\u2013IV, paratracheal<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><em>Fonte: Target Volume Delineation and Field Setup, 2nd Edition (Table 5.1)<\/em><\/p>\n<p>Lymph node involvement runs high due to the extensive submucosal lymphatic plexus. Bilateral cervical and lateral retropharyngeal nodes are commonly affected. Among clinically node-negative patients, 30\u201335% harbor pathologic nodal disease. Level Ib involvement is rare, ranging between 5% and 20% in node-positive necks. For post-cricoid tumors and pyriform sinus tumors involving the apex, posterior level V, level VI, and superior mediastinal nodes should all be considered \u2014 a detail that can be pivotal for adequate elective volume coverage.<\/p>\n<h2>Diagnostic Workup and AJCC 8 Staging<\/h2>\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" class=\"alignleft lazyload\" data-src=\"https:\/\/rtmedical.com.br\/wp-content\/uploads\/2026\/04\/hypopharyngeal-pet-ct-posterior-pharyngeal-wall.jpeg\" alt=\"PET\/CT axial and coronal views of posterior pharyngeal wall carcinoma showing FDG-avid mass in the hypopharynx\" src=\"data:image\/svg+xml;base64,PHN2ZyB3aWR0aD0iMSIgaGVpZ2h0PSIxIiB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciPjwvc3ZnPg==\" style=\"--smush-placeholder-width: 369px; --smush-placeholder-aspect-ratio: 369\/270;\"><figcaption>Fonte: Target Volume Delineation and Field Setup, 2nd Edition \u2014 PET\/CT of posterior pharyngeal wall carcinoma<\/figcaption><\/figure>\n<p>The vast majority of hypopharyngeal cancers are squamous cell carcinomas. Variants such as verrucous, basaloid squamous, spindle cell, and minor salivary gland carcinomas comprise a minority but should be considered in the differential diagnosis.<\/p>\n<p>Clinical history should focus on tobacco and alcohol use, otalgia (which may indicate CN X involvement), respiratory function, voice quality, and baseline swallowing. These details become critical when considering organ preservation for locally advanced tumors. Physical exam requires palpation of the tongue base to evaluate pre-epiglottic involvement, assessment of laryngeal mobility to detect laryngeal invasion, and testing the thyroid click \u2014 absent in posterior lesions displacing the larynx anteriorly.<\/p>\n<p>Fiberoptic nasopharyngolaryngoscopy is essential for identifying adjacent mucosal subsite involvement and vocal cord fixation. Phonation and Valsalva maneuvers during the exam help visualize the full extent of the hypopharynx, which can be difficult to assess. For the full treatment planning context across all head and neck sites, see our <a href=\"https:\/\/rtmedical.com.br\/en\/target-volume-delineation-field-setup-2\/\">complete guide on target volume delineation<\/a>.<\/p>\n<h3>AJCC 8 Staging \u2014 Hypopharyngeal Carcinoma<\/h3>\n<table>\n<thead>\n<tr>\n<th>Stage<\/th>\n<th>Criteria<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td><strong>T1<\/strong><\/td>\n<td>Tumor limited to one subsite of hypopharynx, \u22642 cm<\/td>\n<\/tr>\n<tr>\n<td><strong>T2<\/strong><\/td>\n<td>Tumor invades more than one subsite or adjacent site, 2\u20134 cm, without hemilarynx fixation<\/td>\n<\/tr>\n<tr>\n<td><strong>T3<\/strong><\/td>\n<td>Tumor >4 cm, or hemilarynx fixation, or extension to esophageal mucosa<\/td>\n<\/tr>\n<tr>\n<td><strong>T4a<\/strong><\/td>\n<td>Invades thyroid\/cricoid cartilage, hyoid bone, thyroid gland, esophageal muscle, or central compartment soft tissue (prelaryngeal strap muscles and subcutaneous fat)<\/td>\n<\/tr>\n<tr>\n<td><strong>T4b<\/strong><\/td>\n<td>Invades prevertebral fascia, encases carotid artery, or involves mediastinal structures<\/td>\n<\/tr>\n<tr>\n<td><strong>N0<\/strong><\/td>\n<td>No regional lymph node metastasis<\/td>\n<\/tr>\n<tr>\n<td><strong>N1<\/strong><\/td>\n<td>Single ipsilateral node \u22643 cm, ENE(\u2212)<\/td>\n<\/tr>\n<tr>\n<td><strong>N2a<\/strong><\/td>\n<td>Single ipsilateral node 3\u20136 cm, ENE(\u2212)<\/td>\n<\/tr>\n<tr>\n<td><strong>N2b<\/strong><\/td>\n<td>Multiple ipsilateral nodes, none >6 cm, ENE(\u2212)<\/td>\n<\/tr>\n<tr>\n<td><strong>N2c<\/strong><\/td>\n<td>Bilateral or contralateral nodes, none >6 cm, ENE(\u2212)<\/td>\n<\/tr>\n<tr>\n<td><strong>N3a<\/strong><\/td>\n<td>Node >6 cm, ENE(\u2212)<\/td>\n<\/tr>\n<tr>\n<td><strong>N3b<\/strong><\/td>\n<td>Any node(s) with clinically overt ENE(+)<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><em>Fonte: Target Volume Delineation and Field Setup, 2nd Edition (Table 5.2)<\/em><\/p>\n<p>Contrast-enhanced CT or MRI should evaluate pre-epiglottic and paraglottic space involvement, laryngeal extension, gross cartilage invasion, soft tissue extension, esophageal invasion, and extracapsular spread. PET\/CT adds significant value for defining subtle inferior apical tumor boundaries \u2014 particularly in pyriform sinus tumors \u2014 and for identifying hypermetabolic nodes that may escape conventional CT evaluation.<\/p>\n<h2>Simulation and Daily Localization<\/h2>\n<p>Position the patient supine with head rest and neck hyperextended. A shoulder pull board helps lower the shoulders out of the beam path. Custom thermoplastic mask immobilization is mandatory for positional reproducibility. In postoperative cases, wire all surgical scars so they can be identified during planning.<\/p>\n<p>Acquire thin-cut 3 mm CT slices from the skull vertex down to T5 with intravenous contrast unless medically contraindicated. Place the isocenter at the arytenoids, the anatomic center of the treatment volume. Daily cone beam CT aligned to the larynx provides ideal localization. Daily kV imaging aligned to bone with weekly CBCT is also acceptable, balancing precision with practicality.<\/p>\n<h2>Target Volume Delineation and Treatment Planning<\/h2>\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" class=\"alignright lazyload\" data-src=\"https:\/\/rtmedical.com.br\/wp-content\/uploads\/2026\/04\/hypopharyngeal-carcinoma-t2n0-pyriform-sinus-planning.jpeg\" alt=\"IMRT dose-painting plan for T2N0 left pyriform sinus SCC showing PTV_6996, PTV_5940, and PTV_5610 on axial PET\/CT, MRI, and planning CT slices\" src=\"data:image\/svg+xml;base64,PHN2ZyB3aWR0aD0iMSIgaGVpZ2h0PSIxIiB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciPjwvc3ZnPg==\" style=\"--smush-placeholder-width: 689px; --smush-placeholder-aspect-ratio: 689\/577;\"><figcaption>Fonte: Target Volume Delineation and Field Setup, 2nd Edition \u2014 IMRT planning for T2N0 pyriform sinus with PET\/CT, MRI, and planning CT<\/figcaption><\/figure>\n<p>IMRT planning is recommended for hypopharyngeal carcinoma. A dose-painting approach delivers 54 Gy at 1.8 Gy per fraction to low-risk subclinical regions and 60 Gy at 2 Gy per fraction to high-risk subclinical regions over 30 fractions, followed by a 10 Gy cone-down to gross disease for a total of 70 Gy over 35 fractions. A single simultaneous integrated boost (SIB) plan delivering 70 Gy in 33\u201335 fractions works equally well. Alternative fractionations such as 70 Gy\/63 Gy\/56 Gy in 35 fractions may also be used.<\/p>\n<p>Extended IMRT plans are preferred over a matched low anterior neck field. The reason is practical: high-risk regions or gross disease frequently sit exactly within the match-line&#8217;s low-dose zone, creating underdosage in critical areas. Early-stage disease (T1N0 or T2N0 per AJCC 8) is uncommon in hypopharyngeal cancer. Definitive radiation is typically preferred for local control, larynx preservation, and maintained speech and swallowing. Because of the high incidence of occult nodal disease and the central location of the hypopharynx, bilateral nodal chains must be included in the target.<\/p>\n<p>Advanced-stage disease (\u2265T3 or node-positive) requires choosing between definitive chemoradiation, laryngectomy plus adjuvant therapy, or induction chemotherapy followed by local treatment (surgery + adjuvant, radiation, or chemoradiation). Larynx-preservation strategies are not ideal for advanced T4, poor baseline function, or patients unlikely to recover function, though they may be considered in selected cases. For complementary principles in <a href=\"https:\/\/rtmedical.com.br\/en\/larynx-cancer-delineation\/\">larynx cancer target delineation<\/a>, see our dedicated article.<\/p>\n<h3>Gross Disease Volumes (70 Gy)<\/h3>\n<table>\n<thead>\n<tr>\n<th>Volume<\/th>\n<th>Definition<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td><strong>GTV_70<\/strong><\/td>\n<td>Primary: all gross disease delineated on CT, MRI, or PET. Nodes: \u22651 cm or suspicious FDG-avid nodes<\/td>\n<\/tr>\n<tr>\n<td><strong>CTV_70<\/strong><\/td>\n<td>At MSKCC, additional CTV margin is not routinely used. If uncertain about disease extent: primary = GTV_70 + 5 mm; nodes = GTV_70 + 3 mm (in general, GTV_70 = CTV_70)<\/td>\n<\/tr>\n<tr>\n<td><strong>PTV_70<\/strong><\/td>\n<td>CTV_70 + 3\u20135 mm (based on daily imaging confidence and estimated setup error)<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><em>Fonte: Target Volume Delineation and Field Setup, 2nd Edition (Table 5.3). Dose suggested for 70 Gy in 2 Gy fractions. When using 70\/60\/54 for gross, high-risk, and low-risk subclinical regions, a SIB for 60 Gy\/2 Gy and 54 Gy\/1.8 Gy with a single 10 Gy cone-down to PTV70 can be used.<\/em><\/p>\n<h3>High-Risk Subclinical Volumes (60 Gy)<\/h3>\n<table>\n<thead>\n<tr>\n<th>Volume<\/th>\n<th>Definition<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td><strong>CTV_60<\/strong><\/td>\n<td><strong>Primary:<\/strong> GTV_70 + 1 cm margin + entire subsite + larynx (hyoid to cricoid). Additional coverage by subsite:<br \/>\u2022 <em>Pyriform sinus:<\/em> arytenoids, paraglottic space, thyroid cartilage (lateral lesions), constrictors\/prevertebral muscle (posterior involvement), pre-epiglottic space or oropharynx (superior extension), post-cricoid area (inferior extension)<br \/>\u2022 <em>Posterior pharyngeal wall:<\/em> prevertebral fascia, retropharyngeal space; adjacent oropharynx if superior extension; proximal cervical esophagus if inferior extension<br \/>\u2022 <em>Post-cricoid:<\/em> pyriform sinuses (superior), cricoid cartilage, cervical esophagus (inferior)<\/p>\n<p><strong>Nodes:<\/strong><br \/>\u2022 Ipsilateral\/N+ neck: lateral retropharyngeal (start at skull base, carotid canal entrance), II\u2013IV with retrostyloid space for superior level II<br \/>\u2022 Inferior tumors, apex involvement, advanced T: cover level VI<br \/>\u2022 Midline post-cricoid\/posterior wall N+: bilateral RP, II\u2013IV, VI bilateral; inferior tumors: paratracheal superior mediastinum<br \/>\u2022 Retropharyngeal coverage in node-positive neck<br \/>\u2022 Consider Ib if level II involved; level V if posterior II\u2013IV nodes<\/p>\n<p><strong>Postoperative:<\/strong> entire surgical bed + bilateral dissected neck with clips and wired scars. Positive margin\/ENE areas: delineate with surgeon and treat to 66 Gy<\/td>\n<\/tr>\n<tr>\n<td><strong>PTV_60<\/strong><\/td>\n<td>CTV_60 + 3\u20135 mm, depending on daily localization confidence<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><em>Fonte: Target Volume Delineation and Field Setup, 2nd Edition (Table 5.4)<\/em><\/p>\n<h3>Low-Risk Subclinical Volumes (54 Gy)<\/h3>\n<table>\n<thead>\n<tr>\n<th>Volume<\/th>\n<th>Definition<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td><strong>CTV_54<\/strong><\/td>\n<td>Contralateral or N0 neck: lateral retropharyngeal nodes (can start at C1), II\u2013IV (level II starts where the posterior belly of the digastric crosses the internal jugular vein). Important exception: midline tumors require bilateral retropharyngeal coverage. Midline N+ tumors: the contralateral neck is also considered high risk<\/td>\n<\/tr>\n<tr>\n<td><strong>PTV_54<\/strong><\/td>\n<td>CTV_54 + 3\u20135 mm, depending on daily localization confidence<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><em>Fonte: Target Volume Delineation and Field Setup, 2nd Edition (Table 5.5)<\/em><\/p>\n<h2>Representative Clinical Cases<\/h2>\n<p>The Memorial Sloan Kettering Cancer Center experience illustrates these volume concepts in practice. In a T2N0 left pyriform sinus case, PET\/CT revealed an FDG-avid lesion extending to midline with the inferior margin approaching the post-cricoid region. T1 post-gadolinium MRI confirmed displacement of the left aryepiglottic fold without definitive supraglottic spread. The SIB plan included PTV_6996 (gross disease), PTV_5940 (high-risk subclinical), and PTV_5610 (low-risk), with bilateral retropharyngeal and retrostyloid coverage, the entire larynx from hyoid to cricoid, and levels IV and VI due to the inferior tumor extent.<\/p>\n<p>In advanced cases such as T3N2c posterior pharyngeal wall SCC, treatment used a sequential cone-down technique: 54 Gy\/1.8 Gy and simultaneously 60 Gy\/2 Gy over 30 fractions, followed by a 10 Gy\/2 Gy boost. Coverage included bilateral retropharyngeal and level II starting at the skull base, with ipsilateral level V on the side with gross nodal disease. The larynx, level VI, and superior mediastinal nodal regions were treated to 54 Gy.<\/p>\n<h2>Postoperative and Post-Induction Radiation<\/h2>\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" class=\"alignleft lazyload\" data-src=\"https:\/\/rtmedical.com.br\/wp-content\/uploads\/2026\/04\/hypopharyngeal-postoperative-ct-planning.jpeg\" alt=\"Postoperative radiation planning CT for cT3N2c hypopharyngeal SCC after pharyngolaryngectomy showing bilateral retropharyngeal and level II-IV coverage\" src=\"data:image\/svg+xml;base64,PHN2ZyB3aWR0aD0iMSIgaGVpZ2h0PSIxIiB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciPjwvc3ZnPg==\" style=\"--smush-placeholder-width: 276px; --smush-placeholder-aspect-ratio: 276\/320;\"><figcaption>Fonte: Target Volume Delineation and Field Setup, 2nd Edition \u2014 Postoperative planning after pharyngolaryngectomy (cT3N2c)<\/figcaption><\/figure>\n<p>Adverse pathologic features warranting postoperative radiation per NCCN guidelines include: positive or close margins, extranodal extension, pT3\u2013T4 primary, pN2\u2013pN3 nodal disease, perineural invasion, vascular invasion, and lymphatic invasion. Adjuvant radiation should start ideally within 6 weeks of surgery to maximize therapeutic benefit.<\/p>\n<p>The entire surgical bed and the dissected node-positive neck belong in the high-risk subclinical region (CTV_60). The dissected node-negative neck can be treated as low-risk subclinical (CTV_54). Areas at risk for positive margin or extracapsular spread should be delineated in conjunction with the surgeon, and this region may receive an escalated dose of 66 Gy.<\/p>\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" class=\"alignright lazyload\" data-src=\"https:\/\/rtmedical.com.br\/wp-content\/uploads\/2026\/04\/hypopharyngeal-target-volume-contouring.jpeg\" alt=\"Axial CT slice showing CTV contouring for postoperative hypopharyngeal carcinoma with surgical bed and bilateral neck delineation\" src=\"data:image\/svg+xml;base64,PHN2ZyB3aWR0aD0iMSIgaGVpZ2h0PSIxIiB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciPjwvc3ZnPg==\" style=\"--smush-placeholder-width: 255px; --smush-placeholder-aspect-ratio: 255\/337;\"><figcaption>Fonte: Target Volume Delineation and Field Setup, 2nd Edition \u2014 Postoperative CTV contouring with surgical bed<\/figcaption><\/figure>\n<p>After induction chemotherapy, fuse pre-chemotherapy imaging for target delineation. The high-risk subclinical volume should include the pre-chemotherapy gross disease extent, with adjacent anatomic sites at risk for microscopic spread factored into coverage. The pre-chemotherapy CTV should be modified for post-treatment anatomical differences, excluding air and bone \u2014 a step that requires care to avoid inadvertently reducing coverage.<\/p>\n<p>The MSKCC experience with concurrent chemoradiation and IMRT for locoregionally advanced laryngeal and hypopharyngeal cancers demonstrated favorable outcomes. The EORTC 24891 trial, with 10-year follow-up, confirmed that laryngeal preservation with induction chemotherapy followed by radiation does not compromise disease control or survival, allowing over 50% of survivors to retain a functional larynx. A randomized phase III trial comparing induction followed by radiation versus concurrent chemoradiation in pyriform sinus carcinoma demonstrated improved survival with the concurrent approach. For the complete overview of all head and neck sites, see our <a href=\"https:\/\/rtmedical.com.br\/en\/target-volume-delineation-field-setup-2\/\">complete guide on target volume delineation and field setup<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Anatomy, AJCC 8 staging, simulation, and target volumes for hypopharyngeal carcinoma. Practical GTV, CTV, and PTV tables from MSKCC.<\/p>\n","protected":false},"author":1,"featured_media":16396,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"ngg_post_thumbnail":0,"fifu_image_url":"","fifu_image_alt":"","footnotes":""},"categories":[266,265,99],"tags":[],"class_list":{"0":"post-13819","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-delineamento-cabeca-pescoco","8":"category-delineamento-volumes","9":"category-radiotherapy"},"aioseo_notices":[],"rt_seo":{"title":"Hypopharynx Target Volume Delineation Guide","description":"Target volume delineation in hypopharyngeal cancer. CTV coverage of piriform sinus, postcricoid region, nodal levels and OAR constraints.","canonical":"","og_image":"","robots":"default","schema_type":"MedicalWebPage","include_in_llms":false,"llms_label":"","llms_summary":"","faq_items":[{"q":"What are the subsites of the hypopharynx for delineation?","a":"The hypopharynx comprises the piriform sinuses, postcricoid region, and posterior pharyngeal wall. Each subsite has distinct patterns of submucosal spread and nodal drainage that directly influence CTV definition and elective nodal coverage."},{"q":"Which nodal levels are included in hypopharyngeal cancer RT?","a":"Bilateral levels II-IV are routinely included, with level VI considered for postcricoid or esophageal inlet involvement. Retropharyngeal nodes are included when the posterior pharyngeal wall is involved. Level V may be added for extensive nodal disease."},{"q":"Why is hypopharyngeal cancer challenging for delineation?","a":"Hypopharyngeal tumors often present at advanced stage with extensive submucosal spread that is difficult to visualize on CT alone. The proximity to the esophageal inlet, larynx, and cervical spine requires careful margin design to balance coverage and toxicity."}],"video":[],"gtin":"","mpn":"","brand":"","aggregate_rating":[]},"_links":{"self":[{"href":"https:\/\/rtmedical.com.br\/en\/wp-json\/wp\/v2\/posts\/13819\/"}],"collection":[{"href":"https:\/\/rtmedical.com.br\/en\/wp-json\/wp\/v2\/posts\/"}],"about":[{"href":"https:\/\/rtmedical.com.br\/en\/wp-json\/wp\/v2\/types\/post\/"}],"author":[{"embeddable":true,"href":"https:\/\/rtmedical.com.br\/en\/wp-json\/wp\/v2\/users\/1\/"}],"replies":[{"embeddable":true,"href":"https:\/\/rtmedical.com.br\/en\/wp-json\/wp\/v2\/comments\/?post=13819"}],"version-history":[{"count":2,"href":"https:\/\/rtmedical.com.br\/en\/wp-json\/wp\/v2\/posts\/13819\/revisions\/"}],"predecessor-version":[{"id":16431,"href":"https:\/\/rtmedical.com.br\/en\/wp-json\/wp\/v2\/posts\/13819\/revisions\/16431\/"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/rtmedical.com.br\/en\/wp-json\/wp\/v2\/media\/16396\/"}],"wp:attachment":[{"href":"https:\/\/rtmedical.com.br\/en\/wp-json\/wp\/v2\/media\/?parent=13819"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/rtmedical.com.br\/en\/wp-json\/wp\/v2\/categories\/?post=13819"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/rtmedical.com.br\/en\/wp-json\/wp\/v2\/tags\/?post=13819"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}