Measured Thickness
Description
Measured Thickness, or height, the thickness of a uveal melanoma or conjunctival melanoma, is a prognostic indicator for these tumors.
This data items measures tumor thickness, height, or depth (vertical dimension), rather than size (lateral dimension) or basal diameter (horizontal dimension). (For basal diameter, see NAACCR Data Item #3887-Measured Basal Diameter).
The depth of invasion or tumor thickness measurement for melanomas of the choroid, ciliary body, iris, and conjunctiva is collected in *tenths* of millimeters as stated in the pathology report for the resected specimen. (This is similar to, but not the same as, Breslow depth of invasion, which is measured in tenths of millimeters starting from the stratum granulosum, which is not present in conjunctiva, where the measurement starts at the surface of the conjunctival epithelium.)
Code a measurement specifically labeled as “thickness” “height” or “depth” in the pathology report. In the absence of this label, a measurement described as taken from the cut surface of the specimen can be coded. And in the absence of either of these labels, the third dimension in a statement of tumor size (length x width x depth) can be used by the registrar to code this field.
For conjunctival melanomas, only histopathological measurements are accepted.
Rationale
Measured Thickness is listed as a Registry Data Collection Variable in AJCC. It was previously collected as Uveal Melanoma, CS SSF #3.
Additional Info
**Source Documents:** High-frequency ultrasonography (ultrasound biomicroscopy) report, pathology report, wide-angle fundus camera measurement, clinician report or other documentation in medical record
**Other names include** maximum tumor thickness, depth of invasion, perpendicular tumor diameter (PTD), tumor height
Notes
**Note 1:** **Physician Statement**
* Physician statement of measured thickness, or height, can be used to code this data item when no other information is available. Reference to histopathological measurement is required.
**Note 2:** **Code height not Tumor Size**
* Record actual measurement in millimeters (mm) from clinical documentation, or from a pathology report if surgery performed.
Default
XX.8
Metadata
SSDI
| Code |
Description |
| 0.0 |
No mass/tumor found |
| 0.1-99.9 |
0.1 - 99.9 millimeters (mm)
(Exact measurement to nearest tenth of mm) |
| XX.0 |
100 millimeters (mm) or larger |
| XX.1 |
Described as "less than 3 mm" |
| XX.2 |
Described as "at least" 3 mm |
| XX.3 |
Described as "at least" 6 mm |
| XX.4 |
Described as "at least" 9 mm |
| XX.5 |
Described as "at least" 12 mm |
| XX.6 |
Described as "greater than" 15 mm |
| XX.8 |
Not applicable: Information not collected for this case
(If this information is required by your standard setter, use of code XX.8 may result in an edit error.) |
| XX.9 |
Not documented in medical record
Cannot be determined
Measured Thickness not assessed or unknown if assessed |
