Once pathologists have finished describing lesions, they must interpret what they have found and develop a morphologic diagnosis. A morphologic diagnosis is a short phrase that sums up the important aspects of the lesion and is a way to communicate these aspects to other medical professionals in a precise way.
The components of a morphologic diagnosis are:
- Severity (abbreviated as: s)
- Time (abbreviated as: t)
- Lesion (abbreviated as: l)
- Anatomic site (abbreviated as: a)
These four are the basics, but sometimes other modifiers can be used to refer to Distribution (abbreviated as: d)
For example, if you saw a swollen, dark red spleen that dripped blood when you cut it, the morphologic diagnosis would be:
Similarly, if you saw a kidney with a small wedge-shaped area in the parenchyma that was firm and white/tan and shrunken below the level of the rest of the normal surface, your morphologic diagnosis would be:
Morphologic diagnosis is very, very important (hint-hint). It is the interpretation of the abnormalities which you have just assessed and described.
Some morphologic diagnoses, however, do not have all five components because they do not really fit biologically. For example, neoplasms cannot really be "timed" or graded as to severity. So a morphologic diagnosis of a neoplasm would simply be:
It may seem tough now, but don't worry - you will get a chance to review these concepts and try your hand at coming up with morphologic diagnoses in the "Practice Questions" section.