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Hello everyone.

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Dr. Sidney Levy here, continuing our discussion

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of laryngeal squamous cell malignancy.

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I would like to go over some of the imaging

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features of glottic malignancy, which help

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distinguish it from supraglottic malignancy.

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We have an example of a large transglottic malignancy

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involving all three subsites of the larynx and

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I would like to use it to help demonstrate some points

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which distinguish it from a true glottic malignancy.

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So a true glottic malignancy tends to

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be centered around the true vocal cords

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anteriorly, more commonly than posteriorly.

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Now in this case, we are at the level of the true

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vocal cords, but everything has been effaced.

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So there is no longer any normal vocal cord tissue.

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And indeed, whilst we can find some normal cricoid

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cartilage below, we can't see normal arytenoid cartilages

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which would normally sit here.

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So this tumor is involving the supraglottis

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as well as the glottis and the subglottis.

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And at the level of the glottis,

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there are no longer recognizable structures

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that we can use as normal landmarks.

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And indeed, the thyroid cartilage

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is also involved with tumor.

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But otherwise, glottic tumors have similar

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appearances to supraglottic and subglottic tumors, i.e.,

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they are T1 hypointense to intermediate

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of intermediate T2 signal and tend to

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show variable degrees of enhancement.

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The principles that apply to assessment of cartilage

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in the supraglottic region also apply to assessment

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of cartilage in the glottic and subglottic regions.

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Thanks.

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So I refer to the vignette that has been

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previously taped on supraglottic tumors

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where that has been discussed in more detail.

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But at the level of the glottis, we are looking mainly

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at the thyroid cartilage and the arytenoid cartilages.

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Sometimes also the cricoid cartilage if the

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tumor extends inferiorly into the subglottis.

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It's important to have CT imaging available, as

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with any laryngeal malignancy because sometimes the

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assessment of integrity of laryngeal cartilage is

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greatly aided by the presence of a CT examination.

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An important note to make with glottic

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tumors as opposed to supraglottic

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tumors is that nodal spread is uncommon.

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And the reason for this is that the lymphatic

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supply of the true vocal cords and the glottis

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is sparse in comparison with the rich lymphatic

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supply of the supraglottic structures.

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So that's an important distinction to make.

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In this particular case, there is nodal extension,

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and it is indeed possible and probably likely

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that this tumor originated

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as a supraglottic tumor, which spread into the glottis

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and subglottis, although we can't be sure of that.

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If there is involvement of lymph nodes,

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it's important to remember that glottic tumors

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have a propensity to involve level six, so the

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central compartment anteriorly, which includes

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delphian lymph nodes if there is a large tumor.

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So keep that in mind.

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Not only levels two, three, and

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four, but level six anteriorly

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is particularly associated with glottic tumors.

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One last point that I would like to make about

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glottic malignancy and indeed any laryngeal

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malignancy in particular, as it's very relevant in

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this case, is if there is compromise of the airway

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in particular at the level of the vocal cords,

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this needs to be emphasized in the report and should

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be rung through to the referrer because this is

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actually a source of acute emergency which may

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need to be dealt with immediately as opposed to the

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definitive management of the laryngeal malignancy.

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So in this case, it is fair to say that there is

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moderate to marked stenosis of the laryngeal airway

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at the level of both the supraglottis and the glottis.

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So this is a point that needs to be emphasized

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in the report and rung through to the referrer.