SEER Inquiry System - Search

Following the existing Solid Tumor Rules Histology Rules, it would seem this is a single primary with histology 8045 (Combined small cell carcinoma) because there is no indication there are multiple prostate tumors and Table 2 states combined adenocarcinoma and small cell carcinoma is Combined small cell carcinoma (8045).

Conversely, while not an exact match to this case, SINQ 20190083 implies small cell carcinoma and adenocarcinoma of the prostate are separate primaries. In that SINQ case, the patient was simultaneously diagnosed with metastatic small cell carcinoma of the prostate on a liver biopsy and prostate adenocarcinoma on a prostate biopsy. There is no indication that patient had separate tumors in the prostate, however the SINQ instructs to code as separate primaries.

Would the previous SINQ logic apply to synchronous diagnoses in the prostate as well? Or does code 8045 apply to this situation?

There are four invasive tumors in the right lung:

Large cell undifferentiated carcinoma in the right lower lobe (8012/3, C343);

Adenocarcinoma, acinar-predominant in the right lower lobe (8551/3, C343) that was 0.7 cm in size and limited to the lung;

Mucinous adenocarcinoma in the right upper lobe (8253/3, C341) that was 0.9 cm and limited to the lung;

Adenocarcinoma, NOS also in the right upper lobe (8140/3, C341) that was 1 cm and limited to the lung.

The Lung M Rules confirm the large cell undifferentiated carcinoma is a separate primary from the three adenocarcinoma tumors (Rule M8). The acinar adenocarcinoma and mucinous adenocarcinoma tumors are separate primaries (Rule M6). The adenocarcinoma, NOS tumor is the same primary as both the acinar and mucinous are adenocarcinomas (Rule M7).

How is Primary Site coded for both the acinar and mucinous adenocarcinomas if they represent multiple tumors reported as a single primary (when compared to the adenocarcinoma, NOS tumor)?

Should the adenocarcinoma, NOS tumor also be included when coding EOD Primary Tumor for both the right lower lobe acinar adenocarcinoma and right upper lobe mucinous adenocarcinoma primaries? Further follow-up with the physician is not possible.

The ICD-O-3.2 Coding Table includes Mullerian mixed tumor as the preferred term for histology code 8950 (previously malignant mixed Mullerian tumor/MMMT). This table also includes carcinosarcoma, NOS as the preferred term for histology code 8980. Neither the ICD-O-3.2 Coding Table nor the Implementation Guidelines address the long-standing issue of coding histology for diagnoses of carcinosarcoma/malignant mixed Mullerian tumor.

These endometrial primaries are frequently diagnosed as both carcinosarcoma and MMMT. The questions regarding histology coding for carcinosarcoma and carcinosarcoma/MMMT of the endometrium date back to before the Multiple Primaries/Histology Rules, with at least three SINQ entries instructing registrars not to use code 8950/3 (MMMT) for diagnoses of MMMT. SINQ has instructed registrars that MMMT is a synonym for carcinosarcoma and these tumors should be coded to 8980 (carcinosarcoma), not to 8950 (MMMT). The most recent SINQ is partly inconsistent with the others, indicating 8950 can be used if the tumor is only described as MMMT. The other SINQ entries state carcinosarcoma should be used as it is the preferred term for MMMT. (See SINQ 20061008, 20100009, 20180071.)

The most recent SINQ (20180071) specifically indicates: According to the WHO Classification of Tumors of Female Reproductive Organs, 4th edition, MMMT (8950/3) is now a synonym for carcinosarcoma (8980/3) even though it has a separate ICD-O code. The ICD-O code for MMMT is no longer in the WHO book. However, MMMT is in the ICD-O-3.2 Coding Table and is not stated to be obsolete or a synonym. Which is correct, the clarification in the SINQ or the 2021 ICD-O-3.2 Coding Table?

For a 2021 diagnosis of carcinosarcoma/malignant mixed Mullerian tumor, how should registrars code the histology? Follow the previous SINQ entries and Rule H17 to code the histology to 8980 when the diagnosis includes both carcinosarcoma and MMMT? Do these previous SINQ entries still apply to cases diagnosed 2021 and later?

This question was prompted from preparing SEER*Educate coding exercises. We will use the answer as a reference in the rationales.

Example: Posterior fossa tumor resection final diagnosis was medulloblastoma, WHO Grade IV. The diagnosis comment notes the current tumor resection reveals large irregular reticulin-free nodules with streams of neoplastic cells in a fibrillary background in association with narrow reticulin-rich internodular strands of poorly differentiated neoplastic cells. Taken together, these findings are indicative of medulloblastoma with extensive nodularity. The diagnosis comment provided only one histology.

Per the 2018 Solid Tumor Manual, Malignant CNS, Priority Order for Using Documentation to Identify Histology instructions, an addendum or comment has priority over the final diagnosis. Although indicative is not listed on any ambiguous terminology list, is this an ambiguous diagnosis that must be ignored? Or does the diagnosis comment in this case provide a single, specific diagnosis of medulloblastoma with extensive nodularity?

Per SEER 20140003, an omentectomy is not recorded under Surgery of Other Site when performed with a hysterectomy for an endometrial primary. Is this still correct? CoC appears to have different guidelines stating in a forum that an omentectomy is coded in data item Surgical Procedure to Other Site. I would like to confirm SEER guidelines. Is this one of those unique situations that SEER and STORE differ? Our state follows SEER guidelines and would like to communicate the appropriate rules to our facilities.

If the term discontinuous foci means separate tumors, then rule M14 would apply making these multiple reportable tumors.

For example, chemotherapy and immunotherapy administered first, followed by surgery, then immunotherapy and hormone therapy after surgery. Or is code 4 used for two administrations of chemotherapy before surgery and two more courses after surgery?

The Terms and Definitions Introduction discusses how these are older terms, but pathologists may still use them. In our region, pathologists do, in fact, still use these terms. Can these terms be added to Table 1? For registrars who do not reference the Introduction every time they code histology but go directly to Table 1, coding consistency would likely improve if such terms were added in the Table.

This question was prompted from preparing SEER*Educate coding exercises. We will use the answer as a reference in the rationales.