Small Pigmented Lesion in an Unlabelled Fixative with Missing Clinical Details
At 5 pm, a small hospital laboratory receives a 4 mm pigmented skin lesion excised from the forearm of a 58-year-old man at 3:30 pm. The specimen is in a 20 mL screw-cap container with about 5 mL of clear liquid from an unlabelled bottle; the ward attendant says it is formalin, but the bottle label is faded and the laboratory's formalin stock is kept in another room. The container label has the patient's name and 'skin lesion', but the requisition form has no clinical history and no site. The only histotechnician leaves at 5:30 pm, and the tissue processor is scheduled to start an overnight run at 6 pm. The specimen is small and floats when the container is swirled. The laboratory has 10% neutral buffered formalin, cassettes, biopsy pads and a grossing bench. The clinician who performed the excision has left for the day and is not answering the phone.
1. What should you do when the specimen arrives, and should you reject it? Explain your reasoning.
Read the worked answer
Do not reject the specimen outright. It is a small diagnostic biopsy, and rejection or delay could lose the chance to assess a pigmented lesion. However, do not process it in an unidentified liquid. First check that the patient's name on the container matches the requisition; document the missing site and history. Attempt to contact the ward or clinician and record the calls. If no one can confirm the fixative, remove the tissue from the unknown liquid and place it in fresh 10% neutral buffered formalin. A 4 mm biopsy needs adequate fixation, usually 6-8 hours and preferably overnight, before processing. Fixation now will limit autolysis even if the original liquid was saline or water.
Accept the specimen with a written comment: 'Received in unidentified clear liquid; transferred to 10% neutral buffered formalin at 17:10; clinical site and history missing; clinician not contactable.' Do not discard the original liquid without noting it, and do not invent a site. A small specimen should be wrapped in a biopsy pad or lens paper and placed in a labelled cassette so it is not lost during processing.
2. How should you handle the missing clinical history and the site discrepancy, and what are the risks?
Read the worked answer
The specimen container says only 'skin lesion', while the requisition has no site; the excision note says forearm, but that information is not on the request form. Contact the ward clerk, the operating theatre and the clinician's mobile; if unavailable, send a written query and document the time. Proceed with fixation because delay is harmful, but do not guess the site on the request form. Add a comment that the site is unconfirmed and that the specimen may be from the forearm according to verbal information, clearly marked as unverified.
The risks are significant: site and margin information affect the pathology report, particularly for a pigmented lesion where complete excision and margin assessment matter. A wrong site or wrong patient label can lead to an incorrect diagnosis or further surgery. Use at least two patient identifiers and check whether another specimen with the same surname was received that day. The pathologist should see the discrepancy on the report, and a quality incident should be raised so that request forms and specimen labelling are improved.
3. How should the specimen be processed to avoid loss and preserve diagnostic quality?
Read the worked answer
Fix in 10% neutral buffered formalin with an adequate volume-to-tissue ratio, usually at least 10:1. A 4 mm biopsy should fix for about 6-8 hours; if the processor is due to start at 6 pm, it is safer to delay processing to the next run than to process an under-fixed specimen. Under-fixation causes poor morphology and can make immunohistochemistry unreliable. Record the fixation time.
At grossing, measure the specimen, describe the pigment and margins, and if indicated ink the margins before sectioning. Do not crush the tissue. Place it in a cassette between biopsy pads or in lens paper so it cannot escape; label the cassette with the patient's identifiers. Process overnight, embed, section and stain with H&E; immunohistochemistry can be requested later if needed. Check the block and slide labels against the request. The quality principle is that a short delay with proper fixation is better than rushing a small, poorly fixed specimen through the processor and losing diagnostic material.