Clinical utility of routine pre-operative axillary ultrasound and fine needle aspiration cytology in patient selection for sentinel lymph node biopsy

In patients with operable breast cancer, pre-operative evaluation of the axilla may be of use in the selection of appropriate axillary surgery. Pre-operative axillary ultrasound (US) and fine needle aspiration cytology (FNAC) assessments have become routine practice in many breast units, although the evidence base is still gathering. This study assessed the clinical utility of US+/-FNAC in patient selection for either axillary node clearance (ANC) or sentinel lymph node biopsy (SLNB) in patients undergoing surgery for operable breast cancer. Over a two-year period, 348 patients with a clinically negative axilla underwent axillary US. 67 patients with suspicious nodes on US also underwent FNAC. The sensitivity and specificity of axillary investigations to determine nodal involvement were 56% (confidence interval: 47-64%) and 90% (84-93%) for US alone, and 76% (61-87%) and 100% (65-100%) for FNAC combined with US, respectively. With a positive US, the post-test probability was 78%. A negative US carried a post-test probability of 25%. When FNAC was positive, the post-test probability was greater than unity. A negative FNAC yielded a post-test probability of 52%. All patients with positive FNAC and most patients with suspicious US were listed for axillary node clearance (ANC) after consideration at the multi-disciplinary team (MDT) meeting. With pre-operative axillary US+/-FNAC, 20% of patients were saved a potential second axillary procedure, facilitating a reduction in the overall re-operation rate to 12%. In this study, a positive pre-operative US+/-FNAC directs patients towards ANC. When the result is negative, other clinico-pathological factors need to be taken into account in the selection of the appropriate axillary procedure.

Intra-operative assessment of excision margins using breast imprint and scrape cytology

Local recurrence in breast cancer surgery is related to the completeness of excision. Histological analysis of excision margins is time consuming and impractical for use intra-operatively. Our group evaluated breast imprint and scrape cytology (ISC) for the assessment of excision margins in a feasibility study in 1993-4, with 10 year clinical follow-up. Twenty-six consecutive women undergoing 27 wide local excisions for breast cancer had excision margins prospectively assessed with intra-operative ISC blinded to histology. All ISC results were ready (range 22-30 min) before surgery was completed. ISC agreed with histology in 21/27 (=78%) and disagreed in 6/27 (=22%) of the cases. In two cases with local recurrence, histology was positive in one case, whereas ISC margins were positive in both. Intra-operative ISC is reliable and could help the surgeon to excise more tissue to prevent a second (re-excision) operation. ISC margins may predict clinical outcome, although a larger interventional follow-up study is required.

Intra-operative specimen analysis using faxitron microradiography for excision of mammographically suspicious, non-palpable breast lesions

Recent advances in digital imaging have made Faxitron microradiography an attractive alternative to intra-operative conventional specimen radiography (CSR) for the excision of wire-localized breast lesions. Faxitron specimen analysis time, usefulness of digital image manipulation and re-excision rates were evaluated in comparison to CSR in 299 consecutive wire-localized excisions for mammographically suspicious non-palpable breast lesions (172 procedures with Faxitron, 127 with CSR) in a non-randomized study. The corresponding mean operation times were 34.7 vs. 42.7 min and the respective re-excision rates were 19.8% vs. 31.5% (no significant difference on chi analysis P < 0.1). Faxitron digital image manipulation led to cavity biopsies in 50% (60/121) of the cancer excisions. In 19 of these (16%), histological excision margins were converted from incomplete to complete. The shorter Faxitron mean operating time enables an additional wire-localized operation per theatre list. Digital imaging guides the surgeon for additional cavity biopsies, resulting in re-excision rates as good as CSR.