Reportability/Histology--Heme
& Lymphoid Neoplasms: Is a diagnosis of myeloid stem cell disorder or
myeloid stem cell neoplasm reportable when the differential diagnosis includes
only reportable neoplasms? If so, how should histology be coded? See Discussion.
Pathologists are increasingly using the terms "myeloid stem cell disorder" and "myeloid stem cell neoplasm" to describe reportable myeloid neoplasms. If the pathologist uses these terms and indicates the differential diagnosis includes only reportable neoplasms such as myelodysplastic syndrome, myeloproliferative neoplasm, and acute myeloid leukemia (AML), should this be accessioned as a reportable primary?
Example: The 01/2023 peripheral blood shows high grade myeloid stem cell disorder, and the differential diagnosis includes chronic
myelomonocytic leukemia(CMML) and AML. The patient refused further work-up and expired several days later. No additional information is available.
Report the case when the differential diagnosis includes only reportable neoplasms
in the absence of additional information. We are unable to provide
general instructions for provisional diagnoses as each situation will need to be
reviewed and assessed individually when no further work-up information is available.
Assign myeloid
leukemia, NOS (9860/3) to the case described in the example. Assign a generic histology code because a specific
histology code cannot be assigned when there are several differential diagnoses. Since the differential
diagnoses include a chronic and an acute leukemia, code as myeloid leukemia, NOS since it is not clear if this is chronic or acute.
Solid Tumor Rules/Histology/Behavior--Brain and CNS: How
are histology and behavior coded when the Integrated Diagnosis is
"Meningioma, WHO Grade 2," and the Histological Classification is
"Meningioma with elevated mitotic activity, hypercellularity, necrosis,
and sheeting architecture?" See Discussion.
We are increasingly seeing pathologists use this
terminology to describe WHO G2 meningiomas, but the histology term
"Atypical meningioma" is not being used, and a more specific "Histological
Classification" of other WHO Grade 2 meningiomas (i.e., chordoid or clear
cell meningioma) is not given. Can the combination of meningioma, WHO Grade 2
plus the histological classification listing multiple features of an atypical
meningioma be used to code morphology to 9539/1? Or is this just a meningioma,
NOS 9530/0 despite the WHO Grade 2 classification?
Code meningioma, NOS (9530/0) based on the integrated diagnosis
and histological classification. WHO Classification of Central Nervous System Tumors,
5th edition, states that brain invasion is a criterion for the
diagnosis of CNS WHO grade 2 meningioma, and there is no statement of brain
invasion, atypical meningioma, or other WHO grade 2 lesions. WHO has not
proposed behavior codes based on WHO grade alone.
Reportability/Behavior:
Our registry collects some borderline (behavior /1) cases that are not
reportable to SEER or any other standard setters. Can we assign a behavior code
of /2 to these cases?
Do not assign a behavior code of /2 to these cases unless you
have a way to flag them so that they are not reported to the standard setters
as in situ cases. Work with your state central registry to ensure that these cases are not unintentionally included in state case submission.