EOD Primary Tumor
Notes
**Note 1:** **In-situ and HAMN** * Code 000 (behavior code 2) includes cancer cells confined within the glandular basement membrane (intraepithelial) or described as in situ or high-grade appendiceal mucinous neoplasms (HAMN) **Note 2:** **LAMN** * Code 050 (behavior code 2) for low-grade appendiceal mucinous neoplasms (LAMN) that are confined by the muscularis propria. * See codes 350-750 for LAMN tumors that extend beyond the muscularis propria **Note 3:** **Code 070 (behavior code 3)** * Intramucosal, NOS * Lamina propria * Mucosa, NOS * Confined to, but not through the muscularis mucosa **Note 4:** **Intraluminal extension** * Ignore intraluminal extension to adjacent segment(s) of colon/rectum or to the ileum from the cecum; code depth of invasion or extracolonic spread as indicated. **Note 5:** **Mucinous Tumors** * Mucinous tumors are identified by morphology codes 8480, 8481, and 8490. **Note 6:** **Invasion of subserosa or mesoappendix** * Code 300 when the only statement is "Tumor invades through the muscularis propria into subserosa or mesoappendix but does not extend to serosal surface" and there isn't enough information to clarify subserosa versus mesoappendix. **Note 7:** **Macroscopic adhesions** * Use code 700 for macroscopic adhesions if no pathological confirmation, and for microscopically confirmed tumor in adhesions. * However, if no tumor is present in adhesion(s) upon microscopic examination, the classification is based upon extent of tumor invasion into or through the wall (see codes 100-600). **Note 8:** **Contiguous extension** * Codes 700 and 750 are used for contiguous extension from the site of origin * Except for intraperitoneal metastases limited to the right lower quadrant (RLQ) of the abdomen for **mucinous tumors (see code 600)**, **discontinuous involvement is coded in EOD Mets**.| Code | Description | SS2018 T |
|---|---|---|
| 000 | In situ, intraepithelial, noninvasive (Adeno) carcinoma, noninvasive, in a polyp or adenoma High-grade appendiceal mucinous neoplasm confined by the muscularis propria (HAMN) | IS |
| 050 | Low-grade appendiceal mucinous neoplasm confined by the muscularis propria (LAMN) (in situ) Acellular mucin or mucinous epithelium may invade into muscularis propria | IS |
| 070 | Lamina propria Mucosa (intramucosal, NOS) Muscularis mucosae | L |
| 100 | Submucosa Confined to appendix, NOS Confined to polyp, NOS Localized, NOS | L |
| 200 | Muscularis propria | L |
| 300 | Extension through wall, NOS Invasion through muscularis propria Non-peritonealized pericolic tissues invaded Perimuscular tissue invaded Subserosa * Includes acellular mucin or mucinous epithelium that extends into the subserosa (LAMN tumors) Transmural, NOS Wall, NOS | L |
| 400 | Adjacent tissue(s), NOS Connective tissue Fat, NOS Mesenteric fat Mesentery Mesoappendix * Includes acellular mucin or mucinous epithelium that extends into the mesoappendix (LAMN tumors) * See code 500 if serosa of the mesoappendix is involved Pericolic fat | RE |
| 500 | Invasion of/through serosa (mesothelium) (visceral peritoneum) * Includes acellular mucin or mucinous epithelium involving the serosa of the appendix or serosa of the mesoappendix (LAMN tumors) | RE |
| 700 | Abdominal wall Adherent to other organs or structures Greater omentum Retroperitoneum (excluding fat) Small intestine Tumor found in adhesion(s) if microscopic examination performed | RE |
| 750 | Adrenal (suprarenal) gland Bladder Diaphragm Fallopian tube Fistula to skin Gallbladder Kidney Liver Other segment(s) of colon/rectum via serosa Ovary Ureter Uterus Further contiguous extension | D |
| 800 | No evidence of primary tumor | U |
| 999 | Unknown; extension not stated Primary tumor cannot be assessed Not documented in medical record Death Certificate Only | U |