Generally 10% neutral buffered formalin.
- See also: General notes on fixation
- Measure the length of the appendix.
- Note its shape and thickness
- Cut off about 1.5 cm from the tip and split it in half long the lumen. Divide the remainder into about 3-5 mm thick transverse slices.
- Look mainly for:
- Luminal pus or obstruction, including stones. Carcinoids may hide behind obstructions in the tip.
- Wall defects
- Exterior coatings. Note if it contains "stones" or fruit kernels.
- At least one half of the tip
- A transverse slice closest to the base, that is, the surgical cut.
- At least one transverse slice from an intermediate part.
Particular findings indicating sampling include:
- Wall discoloration
- External green-gray-yellow coating
- Suspected wall defects
- See also: General notes on gross processing
Always look for inflammation and malignancy.
- Neutrophilic infiltrates of the wall of the appendix in the correct clinical context confers a diagnosis of appendicitis. In such case, evaluate depth of the inflammation.
- Also look for any perforation of the wall.
- Look for cancerous cells (also for specimens with clinical appendicitis).
Appendiceal carcinoid. The arrow points out a cluster of neuroendocrine cells. There are also inflammatory cells consistent with acute appendicitis.
Low-grade appendiceal mucinous neoplasm: Minimal cytological atypia of the epithelial cells.
- Description of objective findings.
- Presence or absence of malignancy.
Example, using image at top:
Mucosa with ulceration. No atypia in residual mucosa. Inflammatory cells in the stroma and all muscle layers, as well as on the serosal surface and adherent adipose tissue. No evidence of malignancy. (Optionally: No perforation)
- See also: General notes on reporting
- Monica Dahlgren, Janne Malina, Anna Måsbäck, Otto Ljungberg (1997-02-13). Lilla utskärningen.
- Elkbuli, Adel; Sanchez, Carol; McKenney, Mark; Boneva, Dessy (2019). "Incidental neuro-endocrine tumor of the appendix: Case report and literature review ". Annals of Medicine and Surgery 43: 44–47. doi:10.1016/j.amsu.2019.05.015. ISSN 20490801.
- Hajjar, Roy; Dubé, Pierre; Mitchell, Andrew; Sidéris, Lucas (2019). "Combined Mucinous and Neuroendocrine Tumours of the Appendix Managed with Surgical Cytoreduction and Oxaliplatin-based Hyperthermic Intraperitoneal Chemotherapy ". Cureus. doi:10.7759/cureus.3894. ISSN 2168-8184.