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Hello everyone, Dr. Sidney Levy here.

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3 00:00:05,980 --> 00:00:09,810 Today I'd like to formally stage this left

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piriform sinus squamous cell carcinoma, according

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to principles we've discussed in previous vignettes.

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This is a large tumor with local

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extension, and we will start by T staging it.

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I will refresh everyone's memory on its

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outlines in the axial projection, using

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our post-contrast T1-weighted imaging.

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Similar idea on the pre-contrast T2-weighted imaging.

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And I have a coronal projection to

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help demonstrate it in another view.

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So what are we looking for?

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The first thing is we need to measure it.

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So let's do that.

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It's a large tumor, 3 centimeters in

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the axial projection, four and a half

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centimeters in the superoinferior dimension.

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So therefore, this tumor is greater than four

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centimeters, it automatically qualifies as a T3 tumor.

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We need to decide now whether it is

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going to be upgraded to a T4a or a T4b.

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How do we do that?

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Firstly, what is the local extension of this tumor?

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This tumor is extending into the

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posterior hypopharyngeal wall.

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So, this is piriform sinus here,

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but the tumor has gone beyond that.

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It has crossed the midline, across the posterior hypopharyngeal

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wall, onto the right-hand side,

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the right posterior hypopharyngeal wall.

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That, in and of itself, does not upgrade it to a T4 tumor.

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All that says is that it involves more

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than one subsite of the hypopharynx.

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Next thing, what are the status of the laryngeal cartilages?

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We're at the level of the cricoid

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cartilage here and the thyroid cartilage.

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This tumor closely abuts the posterior

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margin of the thyroid cartilage here.

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It does not contact the cricoid cartilage.

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However, there is no marrow edema or,

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on post-contrast imaging, marrow enhancement.

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And in particular, no cartilage

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erosion on T1 or T2-weighted imaging.

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So, there is no laryngeal cartilage involvement.

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Next thing, does this tumor involve any of the following?

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The hyoid bone?

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No, it does not.

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It is too low for that.

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The hyoid bone is much further up.

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Does it involve the thyroid gland?

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Here is the thyroid gland.

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It is clearly above the thyroid gland.

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So, that's not involved.

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Does it involve esophageal muscle?

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No, it's higher than that,

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so we're not concerned about that.

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And does it involve any of the soft tissues in the central

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compartment, such as the strap muscles and subcutaneous fat?

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It does not.

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So, it's not a T4A tumor, based on what I've said.

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The last thing is, does it show any posterior

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extension which would make it a T4B tumor?

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So we get hold of the sagittal as well as the axial.

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We can see that the tumor does have extension along

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the posterior hypopharyngeal wall, but it does not

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involve prevertebral fascia or the carotid artery.

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And I will demonstrate that for you.

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This is the prevertebral musculature,

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prevertebral fascia covering it, carotid artery.

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Whilst it is close to these structures,

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the tumor does not macroscopically extend into them.

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So therefore, there is not enough on

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radiology to consider this a T4B tumor.

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And lastly, it does not involve the mediastinum.

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In our next vignette, we will end-stage this tumor.