Pathologic M
This input is used in derivation
Notes
**Note 1:** Distant lymph nodes are assigned as M1b. **Distant lymph nodes** Inferior mesenteric lymph nodes Superior mesenteric lymph nodes **Note 2:** Mucinous tumors (morphology codes 8480, 8481, and 8490) with peritoneal involvement confined to the right lower quadrant (RLQ) are classified as T4a and are assigned in T (primary tumor).NAACCR Item
NAACCR #900| Pathologic M | Pathologic M Display | Description | Registrar Notes |
|---|---|---|---|
| c0 | cM0 | No distant metastasis | Unknown; distant metastasis not stated Distant metastasis cannot be assessed Not documented in patient record |
| c1 | cM1 | Distant metastasis | CLINICAL assessment only: Note: M1 has subcategories of M1a and M1b. Assign M1 only when there is no information available to assign one of the subcategories Stated as M1 [NOS] |
| c1A | cM1a | Intraperitoneal metastasis beyond the right lower quadrant, including pseudomyxoma peritonei | CLINICAL assessment only: For mucinous tumors only: Intraperitoneal metastasis BEYOND the right lower quadrant, including pseudomyxoma peritonei Stated as M1a |
| c1B | cM1b | Non-peritoneal metastasis | CLINICAL assessment only: Distant lymph nodes, NOS For mucinous tumors only: Distant lymph node(s) plus intraperitoneal metastasis BEYOND the right lower quadrant, including pseudomyxoma peritonei For non-mucinous tumors only: Any intraperitoneal spread Intraperitoneal spread plus distant lymph node(s) Non-peritoneal metastasis Carcinomatosis Distant metastasis WITH or WITHOUT distant lymph node(s) Distant metastasis, NOS Stated as M1b |
| p1 | pM1 | Distant metastasis | HISTOLOGICALLY confirmed: Note: M1 has subcategories of M1a and M1b. Assign M1 only when there is no information available to assign one of the subcategories |
| p1A | pM1a | Intraperitoneal metastasis beyond the right lower quadrant, including pseudomyxoma peritonei | HISTOLOGICALLY confirmed: For mucinous tumors only: Intraperitoneal metastasis BEYOND the right lower quadrant, including pseudomyxoma peritonei |
| p1B | pM1b | Non-peritoneal metastasis | HISTOLOGICALLY confirmed: Distant lymph nodes, NOS For mucinous tumors only: Distant lymph node(s) plus intraperitoneal metastasis BEYOND the right lower quadrant, including pseudomyxoma peritonei For non-mucinous tumors only: Any intraperitoneal spread Intraperitoneal spread plus distant lymph node(s) Non-peritoneal metastasis Carcinomatosis Distant metastasis WITH or WITHOUT distant lymph node(s) Distant metastasis, NOS |
| 88 | 88 | Not applicable | Primary site/histology not TNM defined Death certificate only (DCO) case |
| <BLANK> | BLANK | See Registrar Notes | Pathologic classification criteria not met No pathologic workup for T and N categories and no pathologic evidence of metastasis Only Pathologic Stage Group documented (no T, N, or M information available) |