Selective lymphoscintigraphy: a necessary adjunct to dye-directed sentinel node biopsy for breast cancer?

Lymphoscintigraphy and triangulated body marking for morbidity reduction during sentinel node biopsy in breast cancer

Current trends in patient care include the desire for minimizing invasiveness of procedures and interventions. This aim is reflected in the increasing utilization of sentinel lymph node biopsy, which results in a lower level of morbidity in breast cancer staging, in comparison to extensive conventional axillary dissection. Optimized lymphoscintigraphy with triangulated body marking is a clinical option that can further reduce morbidity, more than when a hand held gamma probe alone is utilized. Unfortunately it is often either overlooked or not fully understood, and thus not utilized. This results in the unnecessary loss of an opportunity to further reduce morbidity.

Optimized lymphoscintigraphy and triangulated body marking provides a detailed 3 dimensional map of the number and location of the sentinel nodes, available before the first incision is made. The number, location, relevance based on time/sequence of appearance of the nodes, all can influence 1) where the incision is made, 2) how extensive the dissection is, and 3) how many nodes are removed. In addition, complex patterns can arise from injections. These include prominent lymphatic channels, pseudo-sentinel nodes, echelon and reverse echelon nodes and even contamination, which are much more difficult to access with the probe only. With the detailed information provided by optimized lymphoscintigraphy and triangulated body marking, the surgeon can approach the axilla in a more enlightened fashion, in contrast to when the less informed probe only method is used. This allows for better planning, resulting in the best cosmetic effect and less trauma to the tissues, further reducing morbidity while maintaining adequate sampling of the sentinel node(s).

Effect of lymphoscintigraphy drainage patterns on sentinel lymph node biopsy in patients with breast cancer

BACKGROUND

Sentinel lymph node (SLN) biopsy examination is an accepted method of staging breast cancer patients. SLN biopsy examination in patients with drainage to the internal mammary chain (IMC) nodes is controversial.

METHODS

A prospective study of SLN biopsy examination followed by axillary dissection was analyzed to determine how surgeons manage patients with IMC drainage and the rates of axillary SLN identification and positivity in these cases.

RESULTS

Lymphoscintigraphy was performed in 2196 (53.2%) of the 4131 patients in this study. IMC drainage was noted in 80 patients (3.6%). An axillary SLN was identified in 29 of the 40 patients with IMC drainage alone (72.5%). The rate of finding a positive axillary lymph node did not differ based on the lymphoscintigraphic pattern (P = .470).

CONCLUSIONS

Most surgeons do not perform IMC SLN biopsy procedures. Even when lymphoscintigraphy shows isolated drainage to IMC nodes, axillary SLNs usually are identified. Lymphoscintigraphy therefore has limited usefulness.

Lymphatic mapping and sentinel lymphadenectomy for breast cancer

Lymphatic mapping and sentinel lymphadenectomy has become an important tool for axillary lymph node staging in women with early-stage breast cancer. This review examines data regarding the staging accuracy, indications and technical aspects of the procedure, and clinical trials investigating the technique. Multiple studies now confirm that sentinel lymphadenectomy accurately stages the axilla and is associated with less morbidity than axillary dissection. Blue dye, radiocolloid, or both can be used to identify the sentinel node, and several injection techniques may be used successfully. Many patient factors previously thought to affect accuracy of the procedure have now been shown to be of limited significance. The indications for the procedure are expanding, and the histopathologic evaluation of the sentinel node and the role of lymphoscintigraphy have been clarified. Clinical trials are now underway that will determine the prognostic significance of micrometastases and the therapeutic benefit of axillary dissection in women with and without sentinel node metastases. Incorporation of sentinel lymphadenectomy into routine clinical practice will maintain accurate axillary staging with lower morbidity and improved quality of life for women with early-stage breast cancer.

Impact of internal mammary sentinel node imaging in breast cancer

A 28-year-old woman underwent mammary lymphoscintigraphy for evaluation of the sentinel node status of a small infiltrating ductal carcinoma in the central, lower, and outer quadrant of the left breast confirmed by biopsy. The patient was scheduled for lumpectomy and sentinel node biopsy. Lymphoscintigraphy showed increased uptake at two sites of the peritumorally injected tracer (60 MBq; 1.6 mCi rhenium sulfur nanocolloid) in internal mammary nodes, two of which were located most proximal to the tumor and related to the tumor by two distinct lymphatic ducts. An axillary lymph node was also detected. At surgery, the gamma probe confirmed the location of all the hot spots, and four nodes were harvested: one axillary, two first internal mammary nodes in the third intercostal space, and one internal mammary node in the second intercostal space. Histologic analysis revealed that the axillary sentinel node was free of disease, but the two first intramuscular sentinel nodes were metastatic. The second-echelon internal mammary node above the sentinel nodes (second intercostal space) was free of disease. This case shows the benefit of imaging all the drainage pathways of a breast tumor and retrieving nonaxillary lymph nodes, which may be the only positive nodes. As a result of the findings, the patient's prognosis may be altered and the subsequent therapeutic approach may be modified. Although exclusive involvement of the internal mammary chain is well established and relatively rare (occurring in approximately 5% of cases), it is important to remember that the axillary status of a breast tumor is not the only major prognostic factor.

Clinicopathologic analysis of sentinel lymph node mapping in early breast cancer

Axillary nodal status is the most significant prognosticator for predicting survival and guiding adjuvant therapy in breast cancer patients. Sentinel lymph node biopsy (SLNB) represents a minimally invasive procedure with low morbidity for staging axillary nodal status. In this article we review and report our experiences in patients with early breast cancer who underwent SLNB at the Revlon/UCLA Breast Center. Between September 1998 and May 2000, a total 83 SLNBs were performed in 81 patients with proven breast cancer and negative axillary examination who elected to have SLNB as the first step of nodal staging. Two patients had bilateral breast cancer. SLNB was localized by using both 99Tc sulfur colloid (83 cases) and isosulfan blue dye (75 cases). Data of these patients were prospectively collected and analyzed. The clinical and pathologic characteristics of women with positive and negative sentinel lymph nodes (SLNs) were compared to identify features predictive of SLN metastasis. Of the 83 cases, the SLN was successfully localized in 82 (98.8%). Sixty-three percent of patients had SLNs found in level I only, 18.3% in both level I and II, and 4.9% in level II alone. The vast majority (84.3%) of these cases had T1 breast cancer with an average size of 1.55 cm for the entire series. Twenty-three patients (28%) had positive SLNs, with an average of 1.5 positive SLNs per patient. Fifteen had metastases detected by hematoxylin and eosin staining and 8 had micrometastases detected by immunohistochemistry (IHC) using anticytokeratin antibodies. Ten of the former group agreed to and 2 of the latter group opted for full axillary lymph node dissection (ALND). An average of 17.5 lymph nodes were removed from each ALND procedure. Additional metastases or micrometastases were found in seven patients (in a total of 28 lymph nodes). Three patients with completely negative SLNs experienced additional axillary lymph node removal due to their election of free flap reconstruction. None had metastases detected in these lymph nodes. The absence of estrogen and progesterone receptors (ER/PR) by IHC (p = 0.036) and the presence of lymphatic/vascular invasion (LVI) (p = 0.002) predicted positive SLNs in patients with early breast cancer in a univariate analysis; in a multivariate analysis only LVI was predictive (p = 0.0125). Histologic type, nuclear grade, tumor differentiation, HER-2/neu and p53 status, S-phase fraction, and DNA ploidy did not predict SLN status. Immediate postoperative complications were uncommon and delayed complications completely absent. Because of the high detection rate, accurate staging, and minimal morbidity, SLNB should be offered as a choice to women with small breast cancers and clinically negative nodes. Because positive LVI and negative ER/PR status are highly predictive of pathologically positive SLNs in small breast cancers, women whose cancers meet these criteria should be advised preoperatively about their risk of having a positive SLN and may benefit from intraoperative assessment (frozen section and/or touch preparation) of their SLNs.

A selection algorithm for internal mammary sentinel lymph node biopsy in breast cancer

Internal mammary lymph-node (IMN) metastases in breast carcinomas have a major influence on survival, comparable with the influence of axillary lymph-node metastases (ALNM). Prospective, randomized trials have demonstrated that complete IMN dissection as part of extended radical mastectomy does not improve overall or disease-free survival. In the subset of patients with tumours 1cm or less in size and no ALNM, information on IMN status would provide important information. In these cases, the presence of IMN metastases would change the staging from stage I to stage IIIB, according to the current tumour, node and metastasis classification. More importantly, it would influence these patients' adjuvant treatment. Lymphatic mapping for sentinel lymph-node (SLN) biopsy has demonstrated extra-axillary drainage in up to 35% of patients. Recent reports have demonstrated the feasibility of internal mammary sentinel lymph-node (IM-SLN) biopsy. Here we review the general prognostic and clinical significance of tumor location and lymph-node metastases in breast cancer and discuss the specific factors associated with IMN identification, metastases and treatment in the pre-SLN and SLN eras. Based on our review, we propose an algorithm for a selective approach to IM-SLN in breast cancer.

Techniques of sentinel lymph node biopsy

Axillary node status is the single most important prognostic factor for patients with primary breast carcinoma. During the last decade, one of the major advances in breast cancer has been the development of techniques that make axillary staging less morbid and more conservative. The sentinel lymph node (SLN) biopsy technique has received much attention as a possible alternative to axillary lymph node dissection (ALND). The SLN is defined as the first node in the regional lymphatic basin that receives drainage of the primary tumor. We will review the different techniques of lymphatic mapping for breast carcinoma, including radioactive and/or blue dye indicators, timing and site of injection, and preoperative lymphoscintigraphy. The SLN technique involves a multidisciplinary team. It is therefore important that each surgeon validate the technique in his or her own institution to ensure the successful and accurate assessment of the axilla. The SLN technique has modified the surgical management of breast cancer patients, although questions as to its safety have yet to be answered.