SEER Inquiry System - Search

March 2022, left shoulder soft tissue mass excision shows a spindle cell tumor with outside consultation diagnosis of malignant neoplasm with neuroectodermal differentiation and TPR-NTRK1 gene rearrangement. Diagnosis comments indicate the findings most closely resemble the spectrum of kinase-rearranged mesenchymal neoplasms, such as lipofibromatosis-like neural tumor. However, the expression of SOX10 and mature melanocytic markers is unusual, and does not exclude melanocytic differentiation.

Should this be classified as a peripheral neuroectodermal tumor (9364) or as an "NTRK-rearranged spindle cell neoplasm (emerging)" (8990) if there is a NTRK gene rearrangement?

In this case, the surgeon ruptured the ovarian tumor to drain it prior to removal causing the surgical spill. Regional lymph nodes are negative and there is no metastasis. The capsule was then noted as ruptured on pathology.

Does it matter if the surgeon was the one who ruptured the capsule? Would the stage change if the surgeon intentionally ruptured the capsule to drain the tumor intraoperatively causing some surgical spill? The scenarios of an intentional and not intentional rupture are not specified in SEER Summary Stage 2018.

Example: 12/2023 Breast lumpectomy final diagnosis is Invasive ductal carcinoma, lymphoepithelioma-like carcinoma type. This is a single tumor with no in situ carcinoma present.

Lymphoepithelioma-like carcinoma is not listed as a subtype/variant or synonym for breast carcinoma in the Solid Tumor Rules histology tables.

Example: Patient had a 2023 nasopharyngeal mass biopsy showing “Nasopharyngeal non-keratinizing squamous cell carcinoma, undifferentiated type.” 

The Head and Neck Solid Tumor Rules (STRs) do not include an H Rule that instructs us how to code histology when there are two subtypes/variants present for a head and neck primary, nor does the STR define undifferentiated carcinoma as a subtype/variant for 8072.

The WHO Classification of Head and Neck Tumors states non-keratinizing nasopharyngeal carcinoma (non-keratinizing squamous cell carcinoma (SCC) is the most common subtype for nasopharyngeal ca, but that non-keratinizing can be subdivided into undifferentiated and differentiated subtypes.

Should histology be 8020 (undifferentiated carcinoma) or 8072 (non-keratinizing SCC)?

The 2024 Solid Tumor Rules, Table 5: Tumors of the Oropharynx, Base of Tongue, Tonsils, Adenoids contain notes that say beginning 1/1/2022, keratinizing or non-keratinizing SCCs, HPV positive or HPV negative, are coded 8085 or 8086, respectively, for sites listed in the Head and Neck Solid Tumor Rules, Table 5 only.

Table 5 introductory section also states for cases diagnosed 1/1/2023 forward: “When the diagnosis is a subtype/variant of squamous cell carcinoma and HPV status is also noted, code the subtype/variant.” This latter instruction is also included in Other Sites Table 23 (Penis and Scrotum Histologies) as a “Penis Coding Note.”

Do these instructions ONLY apply to sites on those tables (and only to Penis or to Scrotum also in Table 23)? How should we code HPV-related keratinizing/non-keratinizing or other subtype/variant SCCs, for sites NOT on those tables, given the fact that only the more common histologies are listed in the Solid Tumor tables? For example, we recently reviewed a case with HPV-positive basaloid squamous cell carcinoma of the anus (C21.0).

The SEER Manual seems to give somewhat conflicting instructions for clinical trial therapies under the Neoadjuvant Therapy data item. One section states that limited systemic therapy may occur in clinical trials to impact the biology of a cancer, but is not a full course of neoadjuvant therapy with the intent to impact extent of surgical resection or other outcomes (organ preservation, function or quality of life); do not code as neoadjuvant therapy for the purposes of this data item. Then another section states for purposes of this data item, the criteria for neoadjuvant therapy include that treatment must follow recommended guidelines for the type and duration of treatment for that particular cancer site and/or histology, and that neoadjuvant therapy may be given as part of a clinical trial.

For example, a patient was diagnosed with invasive ductal carcinoma of the breast, 6 cm in size; treatment planning conference recommended neoadjuvant chemotherapy. The patient elected to participate in a clinical trial and was assigned to a group given the antibody drug conjugate datopotamab deruxtecan (Dato-DXd) plus durvalumab for 12 weeks. There was no physician documentation of intent or expected outcomes, nor yC staging or statement of clinical response. Post-therapy imaging showed no residual mass, and post-therapy mastectomy path report showed only residual ductal carcinoma in situ, stating "Treatment Effect (after neoadjuvant): Residual Cancer Burden - pCR, In the breast - complete response."  The medical oncologist stated post-therapy stage was ypTis ypN0 cM0.

The trial drugs this patient were given do not appear to be approved or standard neoadjuvant/pre-operative drugs in SEER*Rx or NCCN guidelines for this type of cancer; however, the duration of treatment was fairly substantial, and although we don't have clear documentation from physicians as recommended in the SEER manual (which is usually not stated, in our experience), it seems like they may be considering it as neoadjuvant therapy. How should the Neoadjuvant Therapy data item be coded for cases like this? What is the best way to differentiate between clinical trial therapies that are "limited systemic exposure" (code 3) versus true neoadjuvant therapy (code 1)?

The only Other Sites H Rule related to extramammary Paget disease is included in the Multiple Tumors Abstracted as a Single Primary module. Rule H28 instructs one to code the histology of the underlying tumor when there is extramammary Paget disease and an underlying tumor of the anus, perianal region, or vulva. Therefore, a vulvar extramammary Paget disease with underlying adenocarcinoma is coded as adenocarcinoma (8140/3), and not extramammary Paget disease (8542/3).

However, there is no M Rule confirming extramammary Paget disease and the underlying adenocarcinoma are a single primary (i.e., multiple tumors abstracted as a single primary) making it difficult for one to use the Multiple Tumors Abstracted as a Single Primary H rules module.

We recognize this is a longstanding histology coding rule, but how are registrars supposed to arrive at Rule H28 when the M Rules must be applied first and do not instruct one to accession a single primary? Moreover, if this is to be a single primary (per rule M2), why is there no H Rule in the Single Tumor module?