Download A Practical Guide to Frozen Section Technique

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S.R. Peters
be distracted and many more places for tiny things to hide. We must drive our slide
much more slowly through these tissues. Tissues showing florid proliferative or
inflammatory changes and examining lymph nodes for metastatic tumor are examples
of tissues that need to be examined slowly to capture all that is going on and avoid
missing something hiding in the bushes. It is quite easy to overlook a small area
of goblet cell carcinoid in the one section of inflamed appendix. A focus of vasculitis
or hidden Langhans cells can easily be overlooked in any inflammatory background.
And on busy streets, it is especially important to look for tiny things.
7.2.3 You Can Only Make a Diagnosis if You Think of It
You can be the most well-read, encyclopedic mind in our field but if you are handed a
slide that takes a little thought you will not make a diagnosis unless you think of it. In
our common and most familiar entities, even a small focus of the typical morphology
will immediately flash the correct diagnosis in our mind. As we all know there are
innumerable entities with overlapping morphology. Those we see more rarely and out
of the familiar context, can stay hidden behind the more familiar diagnosis that jumps
out first. If I were to ask you what movie you would like to rent tonight. Off the top of
your head will think of a number of suggestions. But when walking through the video
store, hundreds, of titles will come to mind that you would not have considered.
From the first day I ask our residents to learn the complete classification of diseases
by organ system. I ask them to “Label the files in your head.” As they see cases,
they will add to these files with experience. Having this organized foundation
automatically imparts a level of comfort with the subject. For example even as a
neophyte, if you know the classification of salivary gland tumors and are confronted
with an example you have not seen before, you can go through the files in your
head, exclude the ones you are sure do not fit and read about the ones that are possibilities.
Knowing just the names and a few facts about the entities in the classification
gives you a familiarity with the subject that leaves you with the comfort that you
have considered most of the possibilities. Now consider reading the same slide and
knowing that you only know the names of half of the thirty or more possibilities.
You will never feel secure knowing there are many entities you are not considering,
some of which can have overlapping morphology.
Try throwing up an imaginary chest film with a few vague findings and ask a
group of medical students for their differential diagnosis. Typically, someone will
murmur tumor or pneumonia and not much more. Now open the table of contents
of a general pathology text and read the chapter titles, such as diseases of immunity,
congenital diseases, vascular diseases, and occupational diseases. Suddenly numerous
possibilities will come to mind. They have all learned about diseases such as
Wegoner’s granulomatosis, rheumatoid nodule, asbestosis, silicosis, pulmonary
emboli and numerous others, but unless stimulated, you do not always think of it.
If you think about the pneumonias by class, we will think of bacteria, mycobacterium,
fungi and parasitic pneumonias. If you think about the tumors by classification,