Lymph Node Imaging: Section 2.e.
2.15 Lymph Node Imaging or Imaging the Axilla
2.16 Post-Operative Mammography
2.15 Lymph Node Imaging (of the axilla)
For patients who have a suspicious BI-RADS 4c or 5 lesion on mammography, it is recommended that ultrasound scanning of the ipsilateral axilla should be performed to evaluate any suspicious or abnormal axillary lymph nodes.
Percutaneous fine needle aspiration (FNA) of a lymph node deemed to be suspicious is an appropriate intervention.
If the FNA cytology shows that malignant cells are present in the axillary lymph node, the patient should be evaluated to determine if an axillary lymph node dissection is necessary. The surgeon will perform the lymph node dissection at the same time as the surgery for the primary breast cancer.
2.16 Post-Operative Mammography
Radiographers performing post-op mammograms, look for any residual micro-calcifications after surgical resection. So, a post-op mammogram is necessary if excision margins in surgery are either very close or positive. In addition, if the documentation of the specimen radiograph is not clear about micro-calcifications then a post-op mammogram may also be necessary. (Gluck et al. 1993)
However, if the residual calcifications are suspicious of malignancy on histology, then a re-excision may be necessary.
Post-operative mammography is performed between three to five weeks following excision of a breast cancer and is meant to complement specimen mammography and histologic margin assessment.
Recommendations for DCIS and Micro-Calcifications
In 1998, the American College of Radiology, the American College of Surgeons, the College of American Pathologists and the Society of Surgical Oncology published their guidelines for management of Ductal Carcinoma in Situ (DCIS), especially in the setting of calcifications (Winchester & Strom, 1998).
Residual suspicious breast calcification may be identified in up to 24 % of patients, most of which represent residual DCIS. It is recommended that these suspicious breast calcifications should be removed. The consensus view is that it is better to identify residual breast calcifications prior to any radiation therapy as identification of residual disease may be interpreted as a new disease and may, therefore, prompt a mastectomy.
Gluck, B.S., Dershaw, D.C., Liberman, L., Deutch, B.M.(1993). Microcalcifications on postoperative mammograms as an indicator of adequacy of tumor excision. Radiology. 188(2), 469. (Retrieved October 29th 2014): https://www.ncbi.nlm.nih.gov/pubmed/8327699
Winchester, D.P., Strom, E.A. (1998). Standards for diagnosis and management of ductal carcinoma in situ (DCIS) of the breast. American College of Radiology. American College of Surgeons. College of American Pathologists. Society of Surgical Oncology. CA Cancer J Clin 48(2),108. (Retrieved October, 29th 2014): https://www.ncbi.nlm.nih.gov/pubmed?term=9522825
ICRP Publication 103. The 2007 Recommendations of the International Commission on Radiological Protection. ICRP Publication 103. Ann. ICRP 37 (2-4), 2007http://www.icrp.org/publication.asp?id=ICRP%20Publication%20103
NCCN Guidelines for Patients with Stage 0 Breast Cancer. (Retrieved October 29th 2014): http://www.nccn.org/patients/guidelines/stage_0_breast/index.html