How to read the pathology report

1An example, line by line

This is the text of a real second-opinion report, published by the patient it belongs to¹. The numbers match the notes underneath.

1. Slide consultation, second opinion. The slides from the first biopsy were sent to another pathologist to read. For a rare tumor this is worth asking for: in one series most cases had first been given a different diagnosis².
2. The dates. Service is the day the tissue was taken. Received and reported are when the second laboratory got the slides and when it answered. Here the report came eight days after the tissue was taken.
3. Adnexal carcinoma. A cancer of the skin's appendages: the sweat glands, oil glands and hair follicles. It says what kind of tissue the tumor comes from.
4. Consistent with. Pathologists' wording for a diagnosis that the findings fit. It is less absolute than a flat statement, and is common when a tumor is rare or hard to classify.
5. C44.609. A code for the location, used for billing and registries: skin of the left upper limb, including the shoulder. It describes the site, not the tumor type.
6. The stains. Immunostains show which proteins the cells make. Most myoepithelial tumors stain for epithelial markers, such as keratins, together with S-100 protein³. This pathologist reads CK5/6 with SOX-10 as pointing to myoepithelial cells.
7. Pending, and the addendum. Two more stains were ordered to rule out secretory carcinoma, a different gland cancer. Pending means the result is not in yet. Ask for the addendum when it arrives: it is part of the report.
8. The margin. The surgeon's cut edge is marked with ink. Tumor close to the ink means cancer cells near the edge, so more tissue has to come out. Complete removal with clear margins was associated with better survival⁴.

2What else a report may give

Not every report has these. Each one bears on outlook, so ask if it is missing.

Size

Tumors larger than 5 cm did worse in the pooled literature⁴.

Mitotic rate

More than 10 dividing cells per 10 high-power fields was linked to worse survival⁴.

Necrosis

In one salivary series, no patient whose tumor lacked necrosis developed distant metastases⁵.

Perineural and vascular invasion

Tumor growing along nerves or into vessels. Recorded in 11 and 4 of 25 salivary tumors².

Grade

How abnormal the cells look. Grading of this tumor is described as controversial⁵.

Molecular tests

FISH or sequencing for EWSR1, PLAG1 and other fusions, and a stain for INI1³⁶.

3What to ask for

• A copy of every report, including addenda that arrive later.
• A second opinion on the slides from a center that sees these tumors.
• Whether fusion testing has been done, and if not, whether it can be.
• Where the slides and tissue blocks are stored, in case another center needs them.

The first-steps guide puts these in order. The glossary explains the terms.

4References