Case Study # 2

This is a typical “routine” case that goes completely unnoticed in a surgical pathology laboratory assuming that the clinician does not pay attention (which is true in vast majority of case) to the pathologist’s examination. The case is simple, but there are some snags that can render the pathologist’s diagnosis irrelevant or provide information that can determine the clinical assessment of the case.

Generally, the clinical data available to the grossing person via a requisition form are scarce. This may not be right, but it is a common practice. Nevertheless, the clinical information gives some clues of a chronic process in an elderly person with more than likely diabetes.

In this case, the clinicians would expect answers to the following three questions from the pathologist’s report.

Is the toe gangrenous or it is an ulcer with necrotic tissue around?

Are margins of resection involved?

Is there evidence of osteomyelitis?

Let’s go through the gross description. We will concentrate on diagnostically and methodology significant parts of the report.

What does “portion of toe” mean? It is important to know whether the toe has been completely removed. How many phalanxes are presented?

The description is not helpful in answering the main question: Is this gangrene or an ulcer? The description hints that the defect is closer to an ulcer (“distal [?] Tip is absent”), but does not provide a picture of the layers through the sections.

The second important question is to determine the resection margin status for further clinical action in case the wound does not heal. The description such “The resection margin appears yellow brown and necrotic appearing” is not helpful. The other description “Two full sections through the center of the specimen is submitted for evaluation” does not clarify were they longitudinal or transverse. If the sections were longitudinal, even if they could be accommodated in the cassette, the section requires sophisticated bone cutting through inter phalanx joints. In such situations the pathologist has to determine the location of the resection margin. Transverse sections are not useful because they represent neither the ulcer nor the resection margin.  Separate margin sections and representatives of the specimen through the center or preferably through the defect should be made. “Necrotic” is more the pathologist’s diagnosis prerogative. It would be more appropriate for grossing technician to avoid diagnostic statements and instead concentrate on the color and consistency of tissues at the margin of resection.

“The bone appears softened” hints that osteomyelitis could be found if the bone tissue is processed correctly. Unfortunately, the way of decalcification could not contribute to this question’s answer. The pathologist’s report did not mention osteomyelitis.  “Fibrovascular reaction of bone marrow” occurs in every bone surrounded by necrotic tissue. The pathologist has not diagnosed osteomyelitis. The diagnosis of osteomyelitis requires mild decalcification due to fragility of cellular elements that constitute the inflammatory process.

The specimen in question was collected on 9/26/12 at 14:10. However, it is not clear when the specimen arrived at the laboratory (the time is not printed in the report that is not right for many reason). Anyway, the specimen was processed the next day on 9/27/12. The case was signed out on 9/28/12 at 12:48meaning that the decalcified bone was placed in the tissue processor during 9/27/12, most likely on the evening of that day for overnight processing. Only an acid decalcifier such as RDO can carry out decalcification in a short time. Thus, it means that instead of a mild decalcifier, such as formic acid which preserves the structural components of cellular infiltration in osteomyelitis, a stronger decalcifier (RDO –Hydrochloric acid) was used. By the way, the bone should have been separated from the soft tissue and placed in a separate cassette, otherwise the soft tissue in RDO has artifact of hydrolysis before the bone reaches the end point of decalcification.

Representative sections (this definition is absent in the gross description of the report) should be placed in three cassettes for processing:  ulcer, margin of resection, and bone section.

The pathology report includes the date and time of specimen collection, but the time at which the specimen was received in the laboratory is not present in the report. Although this information is not of importance in the case illustrated above, it can be of significance in other cases.

All these details are important for decent grossing technique practices in the surgical pathology laboratory.  If these details are not fully applied in a routine case, there is no guarantee that a diagnostically significant case will not be spoiled.












Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>