#1: MP/H Rules
Source 1: ICD-O-3
Source 2: 2007 MP/H Rules
MP/H Rules/Histology--Lung: What is the histology of a lung tumor described as solid predominant with mucin production, 8230/3 (Multiple Primaries/Histology (MP/H) Rule 5) or 8255/3 (MP/H Rule 6)? See Discussion.
Pathology report: Left lower lobe lung, Tumor Size: Greatest dimension: 3.0 cm Additional dimensions: 2.5 x 2.0 cm; Tumor Focality: Unifocal; Histologic Type: Invasive adenocarcinoma Solid predominant with mucin production; Histologic Grade: G3: Poorly differentiated. Is the correct histology for this case 8230/3 (rule H5) or 8255/3 (rule H6)?
Code histology as 8230/3, solid adenocarcinoma with mucin formation, using MP/H Rule H3 as one histologic type is identified. All of the histologic terms (solid, mucin production) are covered by 8230/3. Therefore, rule H3 applies. Use the first rule that applies, and stop.