If the size is given by physical examination only, use major TNM T-category headings only (T1, T2, etc .) If size is provided by mammography or pathology report, use subcategories T1a, T1b, etc.
Use TX if the primary tumor was excised at another facility and no information about tumor size is available.
Do not add together the sizes of pieces of tumor removed at biopsy and at resection. Use the largest size of tumor, even if this is from the biopsy specimen. If no size is stated, record as 999 in the field "Size of Tumor".
Multifocal tumors in the same breast that are grossly measureable should be staged according to the size of the largest tumor.
If ductal and lobular neoplasms are diagnosed concurrently in different quadrants of the same breast, the ICD-O site code should be C50.9.
Simultaneous bilateral tumors should be staged separately. Simultaneous is defined as being diagnosed within two months.
Clusters or clumps of cancer cells found in axillary fat that are not specifically identified as lymph nodes are considered to be axillary lymph nodes that have lost their architectural configuration.
If a wedge resection of the breast is performed done for diagnosis and a more complete procedure, such as a modified radical mastectomy, is done as cancer-directed surgery, code the more complete surgical procedure. The
surgical code should indicate the status of the primary organ at the completion of the procedure.
Surgery is the most common treatment for breast cancer. If no surgery was performed, indicate the reason in the "Reason for No Surgery" field.
Fixation to pectoral fascia (the covering of the muscle) does not influence stage.
Paget's disease of nipple without an underlying tumor in the breast is staged as "Tis" disease. Paget's with other disease is measured by the size of the underlying tumor.