Chromatin and nucleoli
Unit 5 of 8
Read the inside of the nucleus, and see what a texture number can carry and what it cannot.
Chromatin is what the inside of the nucleus looks like: even and pale, or coarse, clumped and dark. Papanicolaou is the stain that carries it, which is why this unit runs on Pap patches and the drills on Pap only.
The model's texture input is the standard deviation of the grey values inside the three largest nuclei. A high number means the interior varies a lot. It does not say what is varying, and it cannot resolve a single small structure inside the nucleus.
So the criteria below are read with your eyes, and the number beside them is a summary of the whole interior. Do not let the number stand in for the look.
The criteria, quoted
The high power criteria of a malignant aspirate
A cytologist would look for
high cellularity, prominent dispersal of single cells
crowded tissue fragments with overlapping nuclei
nuclear enlargement, anisonucleosis, pleomorphism of the nuclear margin, size and chromatin, hyperchromasia and prominent nucleoli
a greatly reduced number or total lack of myoepithelial cells associated with the epithelial tissue fragments, and scant or absent bare bipolar nuclei
C2 Benign
A benign breast FNAB diagnosis is made in cases that have unequivocally benign cytological features, which may or may not be diagnostic of a specific benign lesion.
- Risk of malignancy
- 1.4 to 2.3 percent
- Management
If the triple test is benign, no further biopsy is required; if clinical or imaging findings are suspicious, repeat FNAB or proceed to CNB.
The worked example
Loading the case library.
What the machine sees
The eight inputs
- worst radius
- mean of the three largest nuclei's mean radius. Touches nuclear enlargement.
- worst perimeter
- mean of the three largest nuclei's perimeter. Touches nuclear enlargement.
- worst area
- mean of the three largest nuclei's area. Touches nuclear enlargement.
- worst texture
- standard deviation of grey values inside the three largest nuclei. Touches chromatin, in part.
- worst smoothness
- local variation in radius length, three largest nuclei. Touches pleomorphism of the nuclear margin.
- worst concavity
- severity of concave portions of the outline, three largest nuclei. Touches pleomorphism of the nuclear margin.
- worst concave points
- number of concave portions of the outline, three largest nuclei. Touches pleomorphism of the nuclear margin.
- mean concave points
- number of concave portions of the outline, every nucleus. Touches pleomorphism of the nuclear margin.
Not measured here:
- cohesion and architecture (sheets, three-dimensional fragments, dispersal)
- myoepithelial cells and bare bipolar nuclei
- nucleoli
- cellularity of the whole smear
- the background (stroma, mucin, cyst fluid, pus, fat)
- necrosis
- mitoses
A reader who sees only the first column can be right about the size of the nuclei and wrong about the smear. That is why your call comes first and the model answers second.
About 20 trials, 5 to 8 minutes. You can stop at any point.