EOD-Extension--Small Intestine: How do we interpret a pathology description of "extending through serosa and forming masses in the periserosal tissue" for a jejunum primary?
For cases diagnosed 1998-2003:
Code the EOD-Extension field to 55 [Invasion of/through serosa and adjacent connective tissue]. The description states the tumor extended through the serosa into periserosal tissue. The periserosal tissue in this case refers to adjacent connective tissue lying exterior to the intestinal wall and not the (sub)serosal tissue that lies exterior to the muscularis but inferior to the serosa. Analyze each case individually since pathologists are not consistent when using the above terminology.
MP/H Rules/Histology--Endometrium: What is the correct histology code for an endometrial cancer described as "Adenocarcinoma with areas of squamous differentiation?"
Assign 8570/3 to adenocarcinoma with squamous differentiation of the endometrium. The most recent WHO classification does not list "adenocarcinoma" for tumors of the uterine corpus. WHO does state that "endometroid carcinoma of the usual type is a glandular neoplasm..." Further, WHO states "Endometroid carcinoma typically displays a glandular or villoglandular architecture..." Based on the WHO classification, the use of the term "adenocarcinoma" in this context can be interpreted as endometroid carcinoma.
Primary Site: How do you code the primary site when the tumor is identified in a bladder that was reconstructed using a stomach augmentation procedure and the pathology report states, "Bladder/prostate: adenocarcinoma arising within gastric mucosa, with the following features: highly infiltrative through the bladder wall"?
Code the Primary Site field to bladder [C67.9]. Code the location of the tumor as the primary site.
MP/H Rules/Multiple primaries--Breast: How many primaries are reported and what is the histology for each in a case of infiltrating duct and lobular carcinoma of the breast (8522) with Paget disease of the same breast?
Abstract as two primaries according to rule M12. We interpret this as one tumor with infiltrating duct and lobular carcinoma (8522) and a second tumor with Paget disease (8540).
MP/H Rules/Histology--Melanoma: How should histology be coded for a melanoma arising in a compound nevus, NOS or a nevus, NOS?
For cases diagnosed 2007 or later, assign code 8720 [Melanoma, NOS] to melanoma arising in a nevus that does not have a specific code or to melanoma arising in a nevus, NOS.
Currently, ICD-O-3 does not have a specific classification for a melanoma arising in a compound nevus.
MP/H Rules/Histology--Colon: When the microscopic description indicates a colon tumor is "tubulovillous," but the final diagnosis only states "adenocarcinoma," is the histology coded to 8263/3 [adenocarcinoma in a tubulovillous adenoma]?
For cases diagnosed 2007 or later:
Yes. This is an example of a site-specific exception to the general rule to code only from the final diagnosis. The Colon Histology Rules specifically state that "other parts of the pathology report" may be used to identify a tumor arising from a polyp, adenomatous polyp, villous adenoma, or tubulovillous adenoma.
MP/H Rules/Multiple primaries -- Ovary: How many primaries are to be accessioned and what rule applies when a patient has a serous carcinoma of the right ovary treated with neoadjuvant chemotherapy followed by a debulking surgery that revealed a serous tubal intraepithelial carcinoma of the left fallopian tube?
For cases diagnosed 2007 or later, accession two primaries, serous carcinoma of the right ovary and serous tubal intraepithelial carcinoma of the left fallopian tube based on the information provided.
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) and go to the Other Sites MP rules because neither the ovary nor fallopian tube have site specific rules developed.
Start at the MULTIPLE TUMORS module, Rule M3. The rules are intended to be reviewed in consecutive order within a module. The patient has multiple tumors with ICD-O-3 topography codes that are different at the third character (Cxx) and therefore this case should be accessioned as a multiple primary.
It could be helpful to know the extent of involvement noted prior to neoadjuvant therapy and debulking surgery. For example, if the patient had widely metastatic disease throughout the entire pelvis prior to the initiation of treatment, the answer may have been different.
Histology (Pre-2007): What code is used to represent the histology for a "malignant invasive gastrointestinal stromal tumor (GIST)"?
For tumors diagnosed 2001-2006: Malignant GIST is coded 8936/3.
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.
Multiple Primaries/Histology--Mycosis Fungoides/Cutaneous T cell Lymphoma: Physicians often use the terms cutaneous T cell lymphoma (CTCL) and mycosis fungoides interchangeably and yet the SEER Single versus Subsequent Primaries of Lymphatic and Hematopoietic Diseases table indicates that these 2 diagnoses represent separate primaries. Do these cases represent one primary? If so, what histologic type should they be coded to?
For cases diagnosed prior to 1/1/2010:The patient does not have two different malignancies. Code the Histology field to 9700/3 [mycosis fungoides], the specific type of cutaneous T cell lymphoma. Mycosis fungoides is one of several types of cutaneous T cell lymphoma. Physicians often refer to mycosis fungoides by the "umbrella term" cutaneous T cell lymphoma.
The table indicates that the broad category of "T/NK-cell NHL" (which includes CTCL) and mycosis fungoides are presumably separate primaries because several entities are included in that broad category. In the specific case cited above, one entity (CTCL) within the broad category (T/NK-cell NHL) and mycosis fungoides are not separate primaries.
For cases diagnosed 2010 forward, refer to the Hematopoietic and Lymphoid Neoplasm Case Reportability and Coding Manual and the Hematopoietic Database (Hematopoietic DB) provided by SEER on its website to research your question. If those resources do not adequately address your issue, submit a new question to SINQ.