MP/H Rules/Histology--Thyroid: Is a "papillary carcinoma of the thyroid" coded to 8260/3 [Papillary adenocarcinoma] per the ICD-O-3 because it lists "papillary carcinoma of the thyroid" as a synonym for that code or should it be coded to 8050 [Papillary carcinoma, NOS]?
MP/H Rules/Histology--Thyroid: Regarding rule H15, is the mixed code 8340 [Papillary carcinoma, follicular variant] used when there are subtypes of these histologies described, such as a tumor diagnosed with follicular and papillary microcarcinoma or should 8341 [Papillary microcarcinoma] be used?
MP/H Rules/Histology--Urinary System: What is the histology code for a 2007 and later diagnosis of papillary carcinoma of the urinary system organs? See Discussion.
MP/H Rules/Histology/Ambiguous terminology: Can synonyms of listed terms, such as "variety" for the list termed "type," be used to code a more specific histology? See Discussion.
MP/H Rules/Histology/Behavior--Ovary: How are these fields coded for a 20 cm borderline mucinous tumor with a 0.3 cm minor focus of intraepithelial carcinoma of the ovary that the pathologist stages as T1a?
MP/H Rules/Histology: How is histology coded for a diagnosis of "poorly differentiated endometrioid adenocarcinoma intermixed with osteoid sarcomatous component, consistent with malignant mixed mullerian tumor with heterologous (osteosarcoma) elements"? Is malignant mixed mullerian tumor synonymous with carcinosarcoma? See Discussion.
MP/H Rules/Histology: In the absence of a tissue diagnosis, should the histology field be coded based on the findings of a suspicious cytology or a CT scan that clinically confirmed the diagnosis? See Discussion.