Cellular Classification of Breast Cancer

The following is a list of breast cancer histologic classifications.[1] Infiltrating or invasive ductal cancer is the most common breast cancer histologic type and comprises 70% to 80% of all cases.

• Carcinoma, NOS (not otherwise specified).

• Ductal.
  • Intraductal (in situ).
  • Invasive with predominant intraductal component.
  • Invasive, NOS.
  • Comedo.
  • Inflammatory.
  • Medullary with lymphocytic infiltrate.
  • Mucinous (colloid).
  • Papillary.
  • Scirrhous.
  • Tubular.
  • Other.

• Lobular.
  • In situ.
  • Invasive with predominant in situ component.
  • Invasive.[2]

• Nipple.
  • Paget disease, NOS.
  • Paget disease with intraductal carcinoma.
  • Paget disease with invasive ductal carcinoma.

• Other.
  • Undifferentiated carcinoma.

The following are tumor subtypes that occur in the breast but are not considered to be typical breast cancers:

• Phyllodes tumor.[3,4]
• Angiosarcoma.
• Primary lymphoma.

References

1. Breast. In: Edge SB, Byrd DR, Compton CC, et al., eds.: AJCC Cancer Staging Manual. 7th ed. New York, NY: Springer, 2010, pp 347-76. 
   
   
2. Yeatman TJ, Cantor AB, Smith TJ, et al.: Tumor biology of infiltrating lobular carcinoma. Implications for management. Ann Surg 222 (4): 549-59; discussion 559-61, 1995.  [PUBMED Abstract]
   
   
3. Chaney AW, Pollack A, McNeese MD, et al.: Primary treatment of cystosarcoma phyllodes of the breast. Cancer 89 (7): 1502-11, 2000.  [PUBMED Abstract]
   
   
4. Carter BA, Page DL: Phyllodes tumor of the breast: local recurrence versus metastatic capacity. Hum Pathol 35 (9): 1051-2, 2004.  [PUBMED Abstract]