MP/H Rules/Histology--Thyroid: Is a "papillary carcinoma of the thyroid" coded to 8260/3 [Papillary adenocarcinoma] per the ICD-O-3 because it lists "papillary carcinoma of the thyroid" as a synonym for that code or should it be coded to 8050 [Papillary carcinoma, NOS]?
For cases diagnosed 2007 or later, assign code 8260 [papilary carcinoma of the thyroid].
MP/H rules/Histology--Breast: How many primaries and what histologies are coded for a left breast when a bi-lumpectomy path reveals one tumor with a microscopic focus of mucinous adenocarcinoma and extensive DCIS and a second .9 cm mucinous adenocarcinoma with extensive DCIS, and the subsequent mastectomy reveals foci of residual DCIS and Paget's disease of the nipple?
For cases diagnosed 2007 or later:
There are two primaries. Primary 1: The two tumors described on the pathology report from the lumpectomy are a single primary using rule M13. Primary 2: Disregard the foci of residual DCIS. Paget disease of the nipple is a separate primary using rule M12.
Primary 1: invasive mucinous adenocarcinoma and extensive ductal carcinoma in situ: Code the histology as 8480/3 [mucinous adenocarcinoma] using rule H27.
Primary 2: Paget disease of nipple: Code the histology as 8540/3 [Paget disease] using rule H14.
MP/H Rules/Histology--Prostate: If a patient is stated to have prostate "cancer" but a pathology report is not available nor is a specific histology stated in the medical record, can this histology be coded to 8140 [adenocarcinoma] instead of 8000/3 [cancer] because the vast majority of prostate cancers are adenocarcinomas?
For cases diagnosed 2007 and later, the correct histology code is 8000/3 [cancer]. The steps used to arrive at this decision are:
Open the Multiple Primary and Histology Coding Rules Manual. Choose one of the three formats (i.e., flowchart, matrix or text). Go to the Other Sites Histology rules because no specific rules have been developed for prostate primaries.
To determine the histology, start at the SINGLE TUMOR: INVASIVE ONLY module, rule H8. The rules are intended to be reviewed in consecutive order within a module. Code the histology documented by the physician when there is no pathology/cytology specimen or the pathology/cytology report is not available. Code the histology as 8000/3 [cancer] because that is the only available information. In the absence of a pathology report or any other histologic confirmation, code the histology based on the information available.
Multiplicity Counter/CS Tumor Size: The Multiplicity Counter rule 6c states "Use code 99 when the tumor is described as diffuse". Is code 99 used in all circumstances when tumor size is coded to 998? See Discussion.
The CS manual lists esophagus, stomach, familila/familial polyposis (colon), lung, and breast as the only circumstances when code 998 is valid. If this is correct, then if TS is coded to 998, then Multiplicity Counter must be 99.
If the number of tumors is known, code the number in Multiplicity Counter. If the number of tumors is not known, assign code 99. If "diffuse" is the only information available to describe the tumor, assign code 99.
Multiplicity Counter--Thyroid: How is multiplicity counter to be coded for a thyroid cancer presenting as multiple foci? See Discussion.
Thyroidectomy showed papillary thyroid carcinoma. Path diagnosis: tumor focality: multifocal. Path described 3 foci of tumor on each side. The main tumor mass in right thyroid was 1.5 cm. Smaller foci of tumor ranged in size from .1 cm to 1.0 cm. Per guidelines, "we still don't count foci as tumors for the purpose of these rules, even if there is more than one." The 1 cm tumor was probably macroscopic in size. Do we count it in the multiplicity counter? Do we count only the 1.5 cm main tumor mass?
If the number of tumors is known, code the number in Multiplicity Counter. If foci are measured, include them in the multiplicity counter. If the only information available is "multiple foci" assign code 99.
For the case above, code 06 in the multiplicity counter (3 tumors on each side).
MP/H Rules/Histology--Brain: How many primaries are reported and what is the histology for a single brain tumor described as a low grade astrocytoma at the time of the initial partial resection and a low grade glioneuronal neoplasm at the time of the subsequent total resection? See Discussion.
On 4/20/07 a partial resection of a brain tumor is interpreted as low grade astrocytoma. Patient has a gross total resection on 8/13/07 with this diagnosis: low grade glioneuronal neoplasm (see comment). Comment: This case has been reviewed at ---. Dr. agrees with our interpretation (low grade glioneuronal neoplasm, possibly a dysembryoplastic neuroepithelial tumor).
For cases diagnosed 2007 or later, this is a single primary. A single tumor is always a single primary.
Assign histology code 9400/3 [Astrocytoma, low grade]. This diagnosis was not revised or amended based on the later surgery. It is possible that the malignant component was entirely removed during the first surgery.
Multiplicity Counter: Are in situ tumors diagnosed more than 60 days after invasive tumors of the same site and histology included in the Multiplicity Counter?
If an in situ tumor following an invasive tumor is a single primary according to the multiple primary rules for that particular site, include the in situ and the invasive tumors in the multiplicity counter.
Primary Site: For malignant gastrointestinal tumors (GISTs), how should the primary site be coded and which Collaborative Stage and TNM staging schemes should be used for disease found in the stomach, small intestine or other locations?
This answer was provided in the context of CSv1 coding guidelines. The response may not be used after your registry database has been converted to CSv2.Code the primary site to the location where the GIST originated. If the primary site cannot be determined, assign code C809 [Unknown primary site].
GIST of gastrointestinal hollow viscera cannot be staged in TNM.
In Collaborative Staging, use the stomach scheme for GIST of the stomach. Use the small intestine scheme for GIST of the small intestine. For GIST of other primary sites, use the CS scheme for the specific site.
Grade, Differentiation: How is grade coded for cases using the FNCLCC (Federation Nationale des Centres de Lutte Contre Ie Cancer) system? See Discussion.
Is FNCLCC a recognized system in the United States? Tongue was the primary site for the case we saw that used FNCLCC.
Do not code the data item Grade based on the FNCLCC grade. You may record the FNCLCC grade in a text field.