Editing Nasal polyp (section)

==Diagnosis==
[[File:Middle meatus polyp.jpg|alt=Nasal polyp in the middle meatus|thumb|Nasal polyp appearing in the middle meatus.]]
Nasal polyps can be seen on physical examination inside of the nose and are often detected during the evaluation of symptoms. On examination, a polyp will appear as a visible mass in the nostril.<ref name="Murr2016">{{Cite book |last=Murr |first=Andrew |title=Approach to the Patient with Nose, Sinus, and Ear Disorders |date=2016 |publisher=Elsevier/Saunders |isbn=978-1455750177 |pages=2585–2592}}</ref> Some polyps may be seen with anterior rhinoscopy (looking in the nose with a nasal speculum and a light), but frequently, they are farther back in the nose and must be seen by nasal [[endoscopy]].<ref name="Cour2016" /> Nasal endoscopy involves passing a small, rigid camera with a light source into the nose. An image is projected onto a screen in the office so the doctor can examine the nasal passages and sinuses in greater detail. The procedure is not generally painful, but the person can be given a spray decongestant and local anesthetic to minimize discomfort.<ref>{{Cite web |title=Nasal Endoscopy |url=http://care.american-rhinologic.org/nasal_endoscopy |url-status=dead |archive-url=https://web.archive.org/web/20171214060927/http://care.american-rhinologic.org/nasal_endoscopy |archive-date=2017-12-14 |access-date=2017-12-13 |website=care.american-rhinologic.org}}</ref>

Attempts have been made to develop scoring systems to determine the severity of nasal polyps. Proposed staging systems take into account the extent of polyps seen on endoscopic exam and the number of sinuses affected on CT imaging. This staging system is only partially validated, but in the future, may be useful for communicating the severity of disease, assessing treatment response, and planning treatment.<ref name="Mid2014" />

===Types===
There are two primary types of nasal polyps: ethmoidal and antrochoanal. Ethmoidal polyps arise from the [[ethmoid sinuses]] and extend through the [[middle meatus]] into the nasal cavity. Antrochoanal polyps usually arise in the [[maxillary sinus]] and extend into the nasopharynx and represent only 4–6% of all nasal polyps.<ref name="Peds2016">{{Cite book |last=Haddad |first=Joseph |title=Nelson Textbook of Pediatrics |publisher=Elsevier Health Sciences |year=2016 |isbn=978-1455775668 |pages=2010–2011}}</ref>

However, antrochoanal polyps are more common in children comprising one-third of all polyps in this population. Ethmoidal polyps are usually smaller and multiple while antrochoanal polyps are usually single and larger.<ref name="Peds2016" />

===CT scan===
CT scan can show the full extent of the polyp, which may not be fully appreciated with physical examination alone. Imaging is also required for planning surgical treatment.<ref name="Peds2016" /> On a [[CT scan]], a nasal polyp generally has an attenuation of 10–18 [[Hounsfield units]], which is similar to that of [[mucus]]. Nasal polyps may have [[calcification]].<ref>{{Cite web |last=Richard M. Berger |title=Diagnosis: Antral choanal polyp |url=http://www.neurorad.org/nrr/nrr/h28/dx.htm |url-status=live |archive-url=https://web.archive.org/web/20170216045830/http://www.neurorad.org/nrr/nrr/h28/dx.htm |archive-date=2017-02-16 |access-date=2017-02-15 |website=[[University of Kansas School of Medicine]]}}</ref>

===Histology===
[[File:Nasal polyp 25x H+E (1).tif|thumb|Histology of nasal polyp, magnification 25x ([[H&E stain]])]]

On histologic examination, nasal polyps consist of hyperplastic edematous (excess fluid) [[connective tissue]] with some [[seromucous gland]]s and cells representing inflammation (mostly [[neutrophil]]s and [[eosinophil]]s). Polyps have virtually no neurons. Therefore, the tissue that makes up the polyp does not have any tissue sensation and the polyp itself will not be painful.<ref name="Mid2014" /> In early stages, the surface of the nasal polyp is covered by normal respiratory epithelium, but later it undergoes [[metaplasia|metaplastic]] change to squamous type epithelium with the constant irritation and inflammation. The submucosa shows large intercellular spaces filled with serous fluid.<ref>{{Cite book |last=Michaels |first=Leslie |url=https://books.google.com/books?id=Zm3jBwAAQBAJ&pg=PA168 |title=Ear, Nose and Throat Histopathology |date=2012-12-06 |publisher=Springer Science & Business Media |isbn=9781447133322 |page=168 |language=en}}</ref>

===Differential diagnosis===
Other disorders can mimic the appearance of nasal polyps and should be considered if a mass is seen on exam.<ref>{{Cite web |title=Nasal polyps - Symptoms, diagnosis and treatment {{!}} BMJ Best Practice US |url=https://bestpractice.bmj.com/topics/en-us/1130 |access-date=2024-11-19 |website=bestpractice.bmj.com |language=en-us}}</ref> Examples include [[encephalocele]], [[glioma]], [[inverted papilloma]], and cancer.<ref name="Fer2017" /> Early biopsy is recommended for unilateral nasal polyps to rule out more serious conditions such as cancer, [[inverted papilloma]], or [[fungal sinusitis]].<ref name=Murr2016/>
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File:Histopathology of sinonasal inflammatory polyp with mixed inflammation, annotated.jpg|Benign mixed inflammation of an inflammatory nasal polyp.
File:Histopathology of extranodal NK-T cell lymphoma, nasal type.png|[[Extranodal NK/T cell lymphoma, nasal type]] for comparison.<ref>{{Cite journal |last=Takahara M, Kumai T, Kishibe K, Nagato T, Harabuchi Y |year=2021 |title=Extranodal NK/T-Cell Lymphoma, Nasal Type: Genetic, Biologic, and Clinical Aspects with a Central Focus on Epstein-Barr Virus Relation. |journal=Microorganisms |volume=9 |issue=7 |page=1381 |doi=10.3390/microorganisms9071381 |pmc=8304202 |pmid=34202088 |doi-access=free}}<br />- "This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/)."</ref> These lymphoma cells are typically monotonous, with folded nuclei, indistinct nucleoli and moderate amount of cytoplasm.<ref>{{Cite web |last=Mario L. Marques-Piubelli, M.D., Carlos A. Torres-Cabala, M.D., Roberto N. Miranda, M.D. |title=Extranodal NK / T cell lymphoma, nasal type |url=https://www.pathologyoutlines.com/topic/lymphomanonBnasal.html |website=Pathology Outlines}} Last author update: 5 January 2021. Last staff update: 14 October 2021</ref>
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