Primary Site--Unknown & ill-defined site: Should the primary site be coded to C809 [Unknown primary site] or C761 [Thorax, NOS] if the patient died following a limited work-up that included on a cytology on pericardial fluid that was positive for poor differentiated adenocarcinoma?
Primary Site--Unknown & ill-defined site: Is the primary site code C809 [Unknown primary site] preferred over the use of a site code for an organ system (e.g., biliary tract, NOS) or a specific primary site (e.g., colon, NOS) when these are "favored" but other potential sites "cannot be excluded"? See Discussion.
Primary Site--Soft Tissue: How is the primary site coded for a PNET found in the groin when the Tumor Board states the primary is unknown but the SEER site/histology validation table does not allow a site of C809 or C76x to be coded in combination with the histology of 9473/3?
Primary Site--Sarcoma: What is the correct topography code for a partial lung lobectomy with pathology diagnosis of "pulmonary sarcoma with smooth muscle differentiation"? See Discussion.
Primary Site--Peritoneum: During a second look staging lap following a diagnosis of serous carcinoma of the left ovary, did the physician correctly indicate a new peritoneum, NOS primary for disease described as an endometrioid adenocarcinoma in a "paracaval cyst" that appears to have arisen in endometriosis?
Primary Site--Pancreas: Should tumors with the histology "islet cell carcinoma" be coded C25.4 [Islet of Langerhans] even though the tumor location is stated to be in head of pancreas?
Primary Site--Ovary/Peritoneum: When ovaries are not found on a resection or if the ovaries removed are negative for malignancy, but the clinician refers to the adenocarcinoma in the pelvis as being an "ovarian" primary, should the primary site be coded as ovary, pelvic peritoneum or unknown? See discussion.
Primary Site--Ovary/Peritoneum: Should this field be coded to ovary or peritoneum when the bulk of the tumor is in the peritoneum and there is only surface involvement of the ovary?
Primary Site--Ovary/Peritoneum: How should the Primary Site field be coded when no resection is done and it is uncertain whether the primary site is in the ovary or the peritoneum? See discussion.