EOD Mets

Notes

**Note 1:** **Pleural and pericardial effusions** * Most pleural and pericardial effusions with lung cancer are due to tumor * In a few patients, however, multiple cytopathological examinations of pleural and/or pericardial fluid are negative for tumor, and the fluid is non-bloody and is not an exudate. Where these elements and clinical judgment dictate that the effusion is not related to the tumor, the effusion should be excluded as a staging element. * Code 00 in the absence of any other metastasis. **Note 2:** **Extrathoracic metastasis** * Organs * Abdominal organs * Adjacent rib (noncontiguous involvement only) (see *EOD Primary Tumor* for contiguous involvement) * Skin of chest * Separate lesion in chest wall or diaphragm * Distant lymph node(s) - Cervical - Distant lymph node(s), NOS * Carcinomatosis * Distant metastasis WITH or WITHOUT distant lymph node(s)
Code Description EOD 2018 M SS2018 M
00 No distant metastasis Unknown if distant metastasis Tumor Size with Mets for M NONE
10 Pericardial effusion or pleural effusion (malignant) * Ipsilateral, contralateral, bilateral, NOS) Pleural tumor foci or nodules on ipsilateral lung (separate from direct extension) or contralateral lung Pericardial nodules Contralateral lung/main stem bronchus Separate tumor nodule(s) in contralateral lung M1a D
20 Single distant lymph node involved - Cervical - Distant lymph node, NOS WITH or WITHOUT metastasis listed in code 10 M1b D
30 Single extrathoracic metastasis in a single organ * WITH or WITHOUT metastasis listed in code 10 M1b D
40 Multiple extrathoracic metastases in a single organ system *Example: The skeleton is considered one organ. Several metastases in a single bone OR several metastases in several bones are classified as M1c1.* * WITH or WITHOUT metastasis listed in code 10 M1c1 D
45 Multiple extrathoracic metastases in multiple organs system *Example: Liver and distant lymph nodes* WITH or WITHOUT metastasis listed in code 10 M1c2 D
50 Multiple extrathoracic metastases, unknown if single or multiple organ systems M1c D
70 Distant metastasis, NOS M1 D
99 Death Certificate Only M0 U
(1) Fritz AG, Ries LAG (eds). **SEER Extent of Disease 1988: Codes and Coding Instructions (3rd Edition, 1998)**, National Cancer Institute, NIH Pub. No. 98-2313, Bethesda, MD, 1998 (2) Young JL Jr, Roffers SD, Ries LAG, Fritz AG, Hurlbut AA (eds.). **SEER Summary Staging Manual-2000: Codes and Coding Instructions**, National Cancer Institute, NIH Pub. No. 01-4969, Bethesda, MD, 2001. (3) Collaborative Stage Work Group of the American Joint Committee on Cancer. **Collaborative Stage Data Collection System User Documentation and Coding Instructions, version 02.05**. American Joint Committee on Cancer (Chicago, IL) (4) Gress, D.M., Edge, S.B., Gershenwald, J.E., et al. **Principles of Cancer Staging**. In: Amin, M.B., Edge, S.B., Greene, F.L., et al. (Eds.) AJCC Cancer Staging Manual. 8th Ed. New York: Springer; 2017 (5) **Lung**, from the AJCC Cancer Staging System Version 9 (2025). Used with permission of the American College of Surgeons, Chicago, Illinois.