SEER Inquiry System - Search

Updated May 2026

Code as an oropharyngeal primary site and histology as solitary plasmacytoma (9734/3) based on the pathologist's diagnosis of extramedullary plasmacytoma with minimal bone marrow involvement (and a diagnosis consistent with "plasma cell neoplasm" which is not multiple myeloma). Our expert hematopathologist was consulted on this case.

Assign C221 (intrahepatic bile duct) as the primary site for cholangiocarcinoma (8160/3).  Our expert GI pathologist confirms that even when intrahepatic bile ducts are not specifically mentioned, intrahepatic cholangiocarcinoma originates in the intrahepatic bile ducts.

The CPC Validity Status of the site morphology combinations of C569/8441/3 and C569/8441/2 was revised from Valid to Unlikely with the latest release of the Version v24A Edits Metafile. As a result, this site and morphology combination will now require an over-ride flag to be set.

Code as 8461/3 (high-grade serous carcinoma) or 8460/3 (low-grade serous carcinoma) if at all possible. Use 8441/3 (serous carcinoma, NOS) only if it cannot be distinguished as low grade or high grade. The codes for high-grade serous carcinoma and low-grade serous carcinoma are relatively new. High-grade serous carcinoma and low-grade serous carcinoma are very different tumors and pathologists should state whether it is high grade or low grade. Please make every attempt to use the newer codes. If unable to determine high gade versus low grade, assign 8441/3 and override the edit.

The files on the CPC website are currently being updated, and CPC*Search will be updated to reflect the changes sometime this Fall.

For cases diagnosed 2007 or later, code the primary site to ovary [C56.9] and the histology to papillary carcinoma, follicular variant [8340/3].

The steps used to arrive at this decision are:

Refer to the 2012 SEER Manual for help to determine the primary site. This neoplasm is arising in a teratoma of the ovary. Per the 2012 SEER Manual, in this case the site is coded to ovary [56.9] because that is where the tumor originated. Although the teratoma contains thyroid tissue, it arose in the ovary. Teratomas are unusual in that they contain all three germ cell layers from which an embryo forms. It is not unusual to have malignancies that are usually primary to the thyroid, liver, brain, lung, etc., originate in a teratoma.

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 site specific rules have not been developed for this primary.

Start with the SINGLE TUMOR: INVASIVE ONLY module, rule H8. The rules are intended to be reviewed in consecutive order within a module. Code the histology as papillary carcinoma, follicular variant [8340/3].

Code the primary site C031 [Mandibular gingiva]. Code the histology 8033 [sarcomatoid carcinoma]. This tumor originated in the mandibular gingiva and invaded the bone (mandible) -- It did not originate in the bone. This type of tumor does not originate in bone.

For cases diagnosed 2010 and forward, access the Hematopoietic Database at http://seer.cancer.gov/seertools/hemelymph.

Code the primary site to C779 [lymph nodes] per Rule PH22 and the histology to 9591/3 [B-cell lymphoma, NOS].

Code the primary site to C779 [lymph nodes, NOS] when lymphoma is present in an organ and lymph nodes that are not regional for that organ and the origin cannot be determined even after consulting the physician. The patient has involvement of a lumbar spine mass and cervical lymph nodes. Cervical lymph nodes are not regional to the lumbar area of the spine.

Do not use ambiguous terminology to code histology for hematopoietic neoplasms. "Favor" is ambiguous terminology. Therefore, the histology must be coded to B-cell lymphoma and not to diagnosis which is "favored" (Burkitt lymphoma). Remember that ambiguous terminology is only used to determine case reportability, not to code histology for hematopoietic neoplasms.

SEER*Educate provides training on how to use the Heme Manual and DB. If you are unsure how to arrive at the answer in this SINQ question, refer to SEER*Educate to practice coding hematopoietic and lymphoid neoplasms. Review the step-by-step instructions provided for each case scenario to learn how to use the application and manual to arrive at the answer provided. https://educate.fhcrc.org/LandingPage.aspx.

For cases diagnosed 2010 and forward, access the Hematopoietic Database at http://seer.cancer.gov/seertools/hemelymph.

Code the histology to 9735/3 [plasmablastic lymphoma] and the primary site to C809 [unknown] per Rule PH27.

Code the histology specified when the only histology for the case is preceded by ambiguous terminology. For this case, code the histology to plasmablastic lymphoma because it is the only histology mentioned in the diagnosis.

Per the Heme DB Abstractor Notes section for plasmablastic lymphoma, most patients present with Stage III-IV disease. The positive pleural fluid is likely due to advanced disease. In the absence of any other information for this case, Rule PH27 applies, "Code primary site to unknown primary site C809 when there is no evidence of lymphoma in lymph nodes AND the physician documents in the medical record that he/she suspects that the lymphoma originates in an organ(s) OR multiple organ involvement without any nodal involvement."

SEER*Educate provides training on how to use the Heme Manual and DB. If you are unsure how to arrive at the answer in this SINQ question, refer to SEER*Educate to practice coding hematopoietic and lymphoid neoplasms. Review the step-by-step instructions provided for each case scenario to learn how to use the application and manual to arrive at the answer provided. https://educate.fhcrc.org/LandingPage.aspx.

For tumors diagnosed prior to 2007:

Code histology as 8441 [serous adenocarcinoma].

The primary site for this case is fallopian tube, not the suggested site code of ovary.

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.

Determine whether the lesion is on the mucosa or skin based on the pathology report, history and physical, and operative notes when available. The gross description of the pathology report should include information to help in determining whether the site of origin is epithelium (skin) or mucosa (lip).

Do not report the case when the site of origin cannot be determined between a reportable site and non-reportable site for this histology. This includes situations where the site of origin or the site with the greatest involvement is undetermined. In this case, you cannot confirm reportability.