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?
Chemotherapy: If a physician does not document the reason chemotherapy was given concurrently with radiation therapy, should it be assumed to have been used as a radiosensitizer or radioprotectant and then, per SEER chemotherapy coding instruction 2, ignore coding the chemo agent as treatment?
Multiple Primaries (Pre-2007)/Histology (Pre-2007)--Brain and CNS: How many primaries should be abstracted and should the histology field(s) be coded to 9530/1 [Meningiomatosis, NOS] or 9530/0 [Meningioma, NOS] to represent a case that presents with MRI confirmed multiple meningiomas (e.g., left dura, right parasagittal region, and left frontal lobe)?
Multiple Primaries--Lymphoma: Is a diagnosis of mycosis fungoides followed a year later with a biopsy proven diagnosis of anaplastic large T-cell lymphoma stated to represent a transformation of the previous mycosis fungoides reportable as one or two primaries?
Laterality--Breast: Should laterality be coded to 9 [Paired site but no information concerning laterality] or to the side with the positive lymph nodes for a case in which no breast mass is found but positive axillary lymph nodes are found on only one side?
Chemotherapy--Breast: Is chemotherapy administered for inflammatory breast cancer also coded as therapy for an in situ tumor in the contralateral breast?
Histology--Lymphoma: Is histology for "large B-cell lymphoma evolving from extranodal marginal zone B-cell lymphoma" coded to 9680/3 [Malignant lymphoma, large B-cell, diffuse, NOS] or 9699/3 [Marginal zone B-cell lymphoma]?
Histology (Pre-2007): Is histology for an anorectal biopsy of "Cloacogenic carcinoma (squamous cell carcinoma with basaloid features)" coded to 8124/3 [Cloacogenic carcinoma] or 8083/3 [Basaloid squamous cell carcinoma]?