Pediatric Mets

This input is used in derivation

M Category

Notes

**Note 1:** **Benign/borderline tumors** * Code 00 for benign (behavior /0) and borderline (behavior /1) tumors. **Note 2:** **Distant metastasis** * Use code 70 when the only information is “distant metastasis, NOS,” and there is no documentation regarding the specific metastases. * If there are specific metastasis documented that are not listed in codes 15, 25, or 35, or 45, assign code 45 for “other specified distant metastasis.” **Note 3:** **Tumors in the CSF** * The presence of circulating cells in the spinal fluid is coded to 15 WHEN there is no other extension (see codes 25-45) **Note 4:** **Types of extension coded in this data item** * The following adjacent structures/sites, by direct or contiguous extension, are coded to 35. * Adjacent connective/soft tissue * Adjacent muscle * Bone * Major blood vessel(s) * Meninges (e.g., dura) * Multiple/multifocal tumors * Nerves (cranial, NOS) * Ventricular system **Note 5:** **Leptomeningeal metastases** * Leptomeningeal metastases, also known as carcinomatous meningitis and meningeal carcinomatosis, refers to the spread of malignant cells through the CSF space. * These cells can originate from primary CNS tumors (e.g., in the form of drop metastases), as well as from distant tumors that have metastasized via hematogenous spread (code 35). * There are several ways that this spread can occur * **Code 15** when there are circulating cells in cerebral spinal fluid **WITHOUT leptomeningeal metastasis** or other contiguous involvement (see codes 25, 35, 45) * **Code 25** when there is Leptomeningeal metastasis **WITHIN the Brain/CNS** (intracranial spread) and **WITHOUT spinal cord other or contiguous involvement** (see codes 35 & 45) * **Code 35** when there is leptomeningeal metastasis **WITHIN the spinal cord** (extracranial spread) and **WITHOUT other further contiguous involvement** (see code 45) * This includes leptomeningeal metastasis or other extension in the Brain/CNS AND the spinal cord

Default

99

NAACCR Item

NAACCR #1138
Code Description
00 No visible disease on imaging (MRI brain and spine) beyond primary site of disease AND no tumor cells into the cerebrospinal fluid (CSF)
15 Tumor cells in the CSF * Circulating cells in cerebral spinal fluid (CSF)
25 Intracranial spread beyond a single lesion Metastasis within CNS and CSF pathways: Brain and CNS only (intracranial) *Note: See code 35 for involvement of the spinal cord* * Carcinomatous meningitis * Drop metastasis * Leptomeningeal metastases * Meningeal carcinomatosis All sites * Bone (skull) (see code 45 for other bone involvement) * Major blood vessel(s) * Meninges (e.g., dura) * Multiple/multifocal tumors * Nerves (cranial, NOS) * Tumor invades or encroaches upon ventricular system Brain tumors (C700, C710-C719) * Anterior cranial fossa * Brain stem * Cerebellum * Cerebrum (cerebral hemisphere) * Contralateral hemisphere * Hypothalamus * Middle cranial fossa * Pallium * Posterior cranial fossa * Suprasellar brain * Tapetum * Thalamus CNS tumors (C701, C709, C720-C729) * Adjacent connective tissue * Adjacent muscle * Brain for cranial nerve tumor(s) * Sphenoid and frontal sinuses(skull) Pineal Gland (C753) * Adjacent connective/soft tissue * Cavernous sinus * Infratentorial and central brain
35 Visible metastasis in spine OR Visible metastasis in cervicomedullary (junction) Metastasis within CNS and CSF pathways: Spinal cord (extracranial) *Note: Includes spinal cord AND Brain/CNS involvement. See code 25 for Brain/CNS involvement only* * Carcinomatous meningitis * Drop metastasis * Leptomeningeal metastases * Meningeal carcinomatosis
45 Extra-neural metastasis All Sites * Blood * Bone (other than skull) (see code 25 for skull) * Bone marrow * Carcinomatosis * Distant lymph nodes, NOS * Further contiguous extension * Other specified metastasis Brain tumors (C700, C710-C719) * Nasal cavity * Nasopharynx * Other direct extension outside CNS * Posterior pharynx CNS tumors (C701, C709, C720-729) * Eye
70 Distant metastasis, NOS
99 Unknown; distant metastasis not stated Not documented in medical record Death Certificate Only
(1) Aitken JF, Youlden D, O’Neill L, Gupta S, Frazier AL, eds. Childhood cancer staging for population registries according to the Toronto Childhood Cancer Stage Guidelines – Version 2. Cancer Council Queensland and Cancer Australia: Brisbane, Australia; 2021.