RA

Appendix

Removal of appendix usually occurs due to acute appendicitis or incidental because of surgery.

  1. Record dimensions (length and diameter including range).

    1. Make note of color (tan/pink, gray/green).

    2. Describe external surface:

      1. Edematous: accumulation of a clear colorless fluid inside the tissue.

      2. Fibrinous Exudate: inflammatory fluid that the body releases in response to an injury or inflammation (thick and sticky).

      3. Hyperemia: increased blood flow in an area, resulting in redness/warmth and swelling.

      4. Purulence: containing/discharging puss.

      5. Perforations: a whole or piercing passing through the wall.

      6. Hemorrhagic: accompanied by or producing excessive bleeding.

    3. If mesoappendix is present, record dimensions, color, and appearance (edema, fibrinous exudate, purulence.)

      1. The mesoappendix is a fold of peritoneum that suspends the veriform (narrow tube-like sac) appendix from the ileum and cecum.

  2. Make a longitudinal section of the tip (long enough to fit into a cassette).

    1. You may ink the serosal side for orientation.

  3. Remainder of the appendix is sectioned at 3 mm intervals.

  4. Record the thickness of the wall. When describing the “wall,” it is referring to the muscularis propria and anything around it. It refers to the entire thickness of the organ (mucosa to serosa).

    1. Mucosa: inner most lining (Epithelium, Lamina propria, Muscularis mucosae).

    2. Submucosa: Connective tissue with blood vessels, lymphatics, and sometimes lymphoid aggregates (common to appendix).

    3. Muscularis propria (externa): Thick muscular wall that propels contents (inner circular vs. outer longitudinal layer).

    4. Serosa: outermost covering (visceral peritoneum), part of the mesoappendix.

  5. Record the diameter of the lumen.

    1. Dilated: Expanded or widened beyond normal.

    2. Fibrosed: Replaced or thickened by fibrous scar tissue.

    3. Constricted: Narrowed or tightened.

  6. Record the condition of the mucosa.

    1. Glistening: Smooth, shiny, and moist in appearance (indicates normal and healthy).

    2. Ulcerated: Eroded or missing mucosal surface, usually due to inflammation.

    3. Hyperemic: Reddened due to increased blood flow (inflammation or irritation).

  7. Contents of the lumen:

    1. Fecalith.

    2. Foreign Body (Seeds, gallstone calculus)

    3. Purulence or blood (acute appendicitis)

    4. Paraisites

    5. Mucin (may be associated with a mucocele or mucinous neoplasm).

    6. Fibrous obliteration: replacement of normal appendiceal lumen with fibrous (scar) tissue.

  8. Submit one longitudinal section of the tip and two transverse sections (one near the resection margin, and one near the tip), including any abnormalities seen (perforations, ulcerations, serositis).

    1. Mucin accumulation in the lumen or any area suspicious for tumor, submit the entire appendix and submit the resection margin in a separate cassette.

Gross Differential Diagnosis

  1. Appendicitis: usually apparent as purulent exudate on the serosal surface of the appendix, often with gross perforation. More subtle cases may appear edematous or may not be grossly apparent.

  2. Neuroendocrine Tumors (Carcinoid, tubular, or goblet cell carcinoid, crypt cell carcinoma): Usually found in the tip of the appendix. Carcinoids are incidental in one out of six specimens. Normal architecture may be effaced (eliminated or made indistinct often by wearing away a surface). Large tumors may be firm (yellow or white), well circumscribed but not encapsulated, and usually look bulbous swelling of the tip.

  3. Endometriosis: Not uncommon finding in the appendix. Often the muscular propria (submucosa) will appear hypertrophied and areas of focal hemorrhage may be present.

  4. Mucocele: Diffuse globular enlargement of the appendix which is filled with mucus. Mucinous cystadenomas and mucinous cystadenocarcinomas have the same appearance. Dilated appendix filled with accumulation of mucus within the lumen; caused by various underlying conditions [Obstruction, Mucinous neoplasm, Inflammation], Appendix is grossly enlarged, cystic, and filled with gelatinous mucin.

  5. Adenocarcinoma: Rare, same gross appearance as a colonic adenocarcinoma. Some tumors may perforate and present as acute appendicitis. May be difficult to distinguish from inflammation grossly.

  6. Cecal diverticulum (thought to be congenital in origin): May be present clinically as appendicitis. Intraoperative, surgeon can find a pericecal abscess with normal appendix and a right colectomy is performed.

Sample Dictation: Received fresh, labeled with patients name and unit number and “Appendix” is a 5 × 0.9 cm appendix with attach mesoappendix (5 × 1 × 0.8 cm). There is a 0.3 cm perforation of the appendiceal wall, 1.5 cm from the tip. The serosal surface is dull and covered with purulent material. The mesoappendix is edematous, tan/brown, and has areas of focal hemorrhage, the mucosal surface os red/brown and ulcerated. There is 0.5 × 0.5 × 0.5 cm brown friable fecalith in the lumen of the proximal appendix.