Tumor Size Pathological

Breast

Notes

**Note:** Exception to rounding rules for **BREAST** primaries: Round tumor sizes greater than 1.0 mm and up to 2.4 mm to 2 mm (002). The purpose of this exception is so that the size recorded in the Tumor Size field will derive the correct AJCC TNM Primary Tumor (T) category for breast primaries. Do **not** apply this instruction to any other site. For this schema, Tumor Size is used with EOD Primary Tumor to derive EOD T. See the [SEER Program Coding Manual](https://seer.cancer.gov/tools/codingmanuals/index.html) for coding instructions.

NAACCR Item

NAACCR #754
Code Tumor Size Description
000 No mass/tumor found
001 1 mm or described as less than 1 mm
002-988 Exact size in millimeters (2 mm to 988 mm)
989 989 millimeters or larger
990 Microscopic focus or foci only and no size of focus is given
998 Alternate descriptions of tumor size for specific sites: Familial/multiple polyposis: - Rectosigmoid and rectum (C19.9, C20.9) - Colon (C18.0, C18.2-C18.9) If no size is documented: Circumferential: - Esophagus (C15.0-C15.5, C15.8-C15.9) Diffuse; widespread: 3/4s or more; linitis plastica: - Stomach and Esophagus GE Junction (C16.0-C16.6, C16.8-C16.9) Diffuse, entire lung or NOS: - Lung and main stem bronchus (C34.0-C34.3, C34.8-C34.9) Diffuse: - Breast (C50.0-C50.6, C50.8-C50.9)
999 Unknown Size not stated Not documented in medical record Size of tumor cannot be assessed Not applicable