Histology (Pre-2007)--Lung: Should the histology "Polymorphic Adenocarcinoma" be coded to 8022/33 [Polymorphic Carcinoma] or 8140/33 [Adenocarcinoma, NOS]?
For tumors diagnosed prior to 2007:
The histology code for pleomorphic adenocarcinoma of the lung is 8140 [Adenocarcinoma, NOS]. According to our pathologist consultant, "Given lung as primary site I prefer 8140. This loses the pleomorphic modifier, but going to 8022 loses the adeno- designation which is more important. Pathologists occasionally use pleomorphic carcinoma for lung tumors which otherwise dont show any adeno or squamous differentiation, for which 8022 would be appropriate, but in this case we do have the adeno designation."
For tumors diagnosed 2007 or later, refer to the MP/H rules. If there are still questions about how this type of tumor should be coded, submit a new question to SINQ and include the difficulties you are encountering in applying the MP/H rules.
Histology (Pre-2007)--Breast: What code is used to represent the histology for a single lesion with "metaplastic carcinoma" and the majority of tumor has sarcomatoid appearance? Squamous cell carcinoma and high grade intraductal carcinoma are also present. Is the term "sarcomatoid" equivalent to sarcoma?
For tumors diagnosed prior to 2007:
For cases diagnosed on or after 1/1/2001: Code the Histology field to 8575/3 [metaplastic carcinoma]. Sarcomatoid is not coded as sarcoma.
The terms metaplastic carcinoma, squamous cell carcinoma and intraductal carcinoma are used, but only the metaplastic and squamous cell carcinomas are invasive. Metaplastic, loosely defined, means tissue that is not normal.
For tumors diagnosed 2007 or later, refer to the MP/H rules. If there are still questions about how this type of tumor should be coded, submit a new question to SINQ and include the difficulties you are encountering in applying the MP/H rules.
Primary Site--Unknown & ill-defined site: Should the primary site be coded to C809 [Unknown primary site] or C761 [Thorax, NOS] if the patient died following a limited work-up that included on a cytology on pericardial fluid that was positive for poor differentiated adenocarcinoma?
Based on the information provided, code the primary site to C809 [Unknown primary site]. There is not enough information provided to suggest that the primary site is the thorax or any other location.
Histology--Heme & Lymphoid Neoplasms: Should the 1995 diagnosis be changed to plasmacytoma? A 1995 case on the central registry database indicates that MRI and bone surveys revealed a pubic ramus lesion that was biopsied. There are no other bone lesions. A bone marrow biopsy was negative. The pathologist's diagnosis at that time was "Plasma Cell Myeloma". In 2013 there was a positive bone marrow biopsy and a diagnosis of Plasma Cell Myeloma. In 2013, a history of "sequential plasmacytomas since 1995" was mentioned. Since the 1995 diagnosis was only a solitary bone lesion with no marrow involvement, it certainly seems to fit a diagnosis of plasmacytoma better than myeloma.
Do not change the 1995 diagnosis in this case. It is best to code the histology according to information from the time of the diagnosis. Using information obtained many years later is less reliable.
Primary Site--Breast: What subsite is to be coded for a case of invasive Paget disease of the nipple with an infiltrating ductal carcinoma of the lower inner quadrant?
Code C50.9 [Breast, NOS]. Code the last digit of the primary site to '9' for single primaries when multiple tumors arise in different subsites of the same anatomic site and the point of origin cannot be determined. Nipple [C50.0] and LIQ [C50.3] fit this rule. This is a single primary per MP/H Breast Rule M9.
EOD Fields--Lymphoma: Was MALT Lymphoma [9715/3 (ICD-O-2) and 9699/3 (ICD-O-3)] inadvertently excluded from SEER EOD manual, top of page 180?
For cases diagnosed 1998-2003:
Yes. Use the scheme on page 180 for MALT lymphoma. The ICD-O-2 morphology code 9715 was omitted in error. It should have been added when the EOD was printed in 1998.
Histology (Pre-2007)--Ovary: Should the histology "endometroid adenocarcinoma arising in a serous fibroadenoma" be coded to 8380 [Endometroid adenocarcinoma, NOS] or 9014 [Malignant serous fibroadenoma]?
For tumors diagnosed prior to 2007:
The best code is 8381/3 [Endometroid adenofibroma, malignant]. According to our pathologist consultant: "Serous 'fibroadenoma' is not exactly standard terminology. I would guess the pathologist is looking at an adenofibroma with more fibro and less adeno and thus has changed the terminology around. The combination of the benign serous and malignant edometrioid is also a bit unusual. Each of the proposed codes is defendable, but I prefer endometrioid adenofibroma, 8381/3, because it puts the tumor in the adenofibroma category (less common) yet still identifies the malignant element (endometrioid), even though it does lose the serous. But anyone wanting to look at malignant adenofibromas would find the case, and we would carry it under the appropriate malignant component."
For tumors diagnosed 2007 or later, refer to the MP/H rules. If there are still questions about how this type of tumor should be coded, submit a new question to SINQ and include the difficulties you are encountering in applying the MP/H rules.
Systemic/Surgery Sequence--Breast: How is this field coded for a breast cancer patient treated with a lumpectomy followed by chemotherapy and then a mastectomy?
Assign code 2 [Systemic therapy before surgery]. The code in Systemic Treatment/Surgery Sequence is related to the surgery coded in Surgery of Primary Site. For SEER, the mastectomy will be coded in the surgery field. The chemotherapy occurred before the mastectomy.
2018 Solid Tumor Rules/Multiple Primaries--Breast: How many primaries should be reported when a left breast simple mastectomy identifies focal Paget disease of the nipple and 12 axillary nodes positive for metastatic lobular carcinoma (no primary lobular breast tumor identified)?
Abstract two primaries, one lobular carcinoma (8520/3) and another one Paget disease of the breast (8540/3) using the 2018 Breast Solid Tumor Rules, Rule M9: Abstract multiple primaries when the diagnosis is Paget disease with underlying tumor which is NOT duct. Example: Paget disease of the nipple with underlying lobular carcinoma are multiple primaries. Additionally, Table 2, Histology Combination Codes, Note 2 states: Lobular carcinoma and Paget are separate primaries (see Lobular carcinoma and any histology in Table 3 with exception of duct carcinoma/carcinoma NST/DCIS (and subtypes/variants) 8500 and Paget disease, in situ and invasive).
While not identified in the pathology of the mastectomy, the lobular carcinoma is likely underlying as it was identified in the axillary lymph nodes. The 2021 SEER Manual states: If the only pathologic specimen is from a metastatic site, code the appropriate histology code and the malignant behavior code (/3). The primary site and its metastatic site(s) have the same histology.