SEER Inquiry System - Report
Produced: 11/28/2024 10:50 PM
Question 20180066
Inquiry Details
References:
#1: Solid Tumor Rules. malignant and non-malignant CNS
#2: 2018 SEER Manual, 95. Laterality
Question:
Solid Tumor Rules (2018)/Laterality--Brain and CNS: How is laterality coded for bilateral non-malignant central nervous system (CNS) or malignant CNS tumors now that laterality is no longer used to identify these tumors as multiple primaries? See Discussion.
Discussion:
The Equivalent Terms and Definitions sections in the Solid Tumor Rules for these schemas identify which sites must have laterality coded, but there is no instruction for coding laterality when bilateral tumors are a single primary. The SEER Manual currently only indicates code 4 (bilateral) is seldom used (e.g., bilateral ovarian tumors, Wilms tumors, etc.) but does not indicate laterality code 4 should be used for CNS tumors. Is this note going to be updated or should a non-bilateral code be applied?
Example: MRI demonstrates multiple left-sided dural-based meningiomas including a 4.4 cm left posterior fossa meningioma, a 0.8 cm left frontal-parietal meningioma and a right posterior frontal meningioma. The large left posterior fossa meningioma was resected and proved atypical meningioma. Should the laterality be 4 (bilateral) as the patient had both left and right-sided meningiomas confirmed to be a single primary? Or should the laterality be coded as 2 (left) since only the large left-sided meningioma was proven to be a borderline tumor (atypical meningioma, 9539/1) and the others were benign?
Answer:
Determine whether the CNS tumors are single or multiple primaries. Multiple cerebral meningiomas are a single primary according to the non-malignant CNS Solid Tumor Rules. Assign laterality using the 2018 SEER Manual for select invasive, benign, and borderline primary intracranial and CNS tumors using codes 1-9 for all sites listed in the Sites for Which Laterality Codes Must Be Recorded table. In the example, assign code 4, bilateral involvement at time of diagnosis, lateral origin unknown for a single primary.
The solid tumor rules are not a one-stop-shop for all coding. Refer to the appropriate coding manual for laterality. We removed laterality for determining multiple primaries in meningiomas as they were being over-reported according to CBTRUS.