Primary site/Histology (Pre-2007)/Behavior: What is the correct site and histology/behavior for the following diagnosis: "mucinous cystadenoma of the appendix with perforation and pseudomyxoma peritonei." This was diagnosed at e-lap for a separate adenocarcinoma of the ascending colon.
For tumors diagnosed prior to 2007:
The appropriate code for mucinous cystadenoma of the appendix with perforation and pseudomyxoma peritonei is C18.1 8470/0. It is not reportable to SEER. According to our pathologist consultant, mucinous cystadenoma is a legitimate term for such appendiceal tumors. They may implant all over the peritoneum as pseudomyxoma peritonei, especially in the face of perforation, without being histologically malignant.
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.
Laterality--Head and Neck: Were the topography codes C090 and C091 intentionally left off of the Sites for Which Laterality Codes Must Be Recorded table in the 2018 SEER Manual? The codes were also removed from Table 10 in the 2018 Solid Tumor Rules for Head and Neck but appear under coding instructions 1b. and 6b. in the manual.
Thank you for bringing this to our attention. C090 and C091 were intentionally removed from the list of sites for which laterality must be coded. They should have also been removed from coding instructions 1b and 6b. We will make that correction in the next version of the manual.
Histology--Pancreas: How is a "gastrin and somatostatin producing endocrine neoplasm" coded that has lymph node metastasis?
The best code available for this situation is 8153/3 [Gastrinoma, malignant].
Many pancreatic endocrine tumors produce more than one peptide, such as gastrin and somatostatin in this case. ICD-O-3 does not provide a code for pancreatic endocrine tumors which produce more than one peptide. According to the WHO Classification of Tumours of Endocrine Organs, there is a distinct hormonal syndrome associated with gastrin producing tumors, and not with many of the somatostatin producing tumors. Therefore, our pathologist consultant advises us to code to gastrinoma in this case.
Multiple Primaries (Pre-2007)--Bladder/Prostatic Urethra: Is the prostatic urethra a new primary for a case with a history of recurrent noninvasive bladder cancer that was subsequently diagnosed with transitional cell carcinoma in situ of the prostatic urethra and had a subsequent clinical diagnosis of "refractory bladder carcinoma"?
For tumors diagnosed prior to 2007:
If the histology of the bladder primary is "transitional cell carcinoma" or "papillary transitional cell carcinoma," do not code the prostatic urethra as a new primary. This is probably a case of intraluminal (mucosal) spread of the original tumor, rather than separate primaries. The clinical diagnosis supports this view.
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/Behavior--Brain and CNS: How should Histology and Behavior be coded for a polymorphous low-grade neuroepithelial tumor of the young (PLNTY) arising in the brain?
Reportability/Breast: Is lobular carcinoma in situ (LCIS) reportable? The eighth edition, American Joint Commission on Cancer (AJCC) Cancer Staging Manual does not stage LCIS.
Yes, LCIS is reportable. Staging does not determine reportability. Follow the reportability requirements of your state and national standard setter. SEER reportability requirements are found in the SEER manual starting on page 5, https://seer.cancer.gov/manuals/2016/SPCSM_2016_maindoc.pdf
MP/H Rules--Breast: Is inflammatory breast cancer always one primary per lifetime? Or is a subsequent inflammatory breast cancer a second primary if diagnosed more than five years later?
For cases diagnosed 2007 or later, a diagnosis of inflammatory breast cancer more than five years after a previous diagnosis of inflammatory breast cancer is a separate (new) primary. See rule M5 in the Breast Multiple Primary Rules.
Reportability--Appendix: Are low-grade appendiceal mucinous neoplasms reportable?
For cases diagnosed prior to 1/1/2022
A low-grade appendiceal mucinous neoplasm (LAMN) is not reportable. The WHO classification designates LAMN with the behavior code /1 [uncertain whether benign or malignant].
Primary Site: How is this field coded for cholangiocarcinoma involving the intrapancreatic bile duct?
Code the primary site as C24.0 [Extrahepatic bile duct, includes Common bile duct] for a cholagiocarcinoma originating in the common bile duct. A portion of the common bile duct is within the head of the pancreas: The intrapancreatic segment of the common bile duct.