Training simulator for sentinel node biopsy (SLNB)

A low cost training phantom model for radio-guided localization techniques in occult breast lesions

Radio-guided localization (RGL) for identifying occult breast lesions has been widely accepted as an alternative technique to other localization methods, including those using wire guidance. An appropriate phantom model would be an invaluable tool for practitioners interested in learning the technique of RGL prior to clinical application. The aim of this study was to devise an inexpensive and reproducible training phantom model for RGL. We developed a simple RGL phantom model imitating an occult breast lesion from inexpensive supplies including a pimento olive, a green pea and a turkey breast. The phantom was constructed for a total cost of less than $20 and prepared in approximately 10 min. After the first model's construction, we constructed approximately 25 additional models and demonstrated that the model design was easily reproducible. The RGL phantom is a time- and cost-effective model that accurately simulates the RGL technique for non-palpable breast lesions. Future studies are warranted to further validate this model as an effective teaching tool.

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).

Using the intraoperative hand held probe without lymphoscintigraphy or using only dye correlates with higher sensory morbidity following sentinel lymph node biopsy in breast cancer: a review of the literature

BACKGROUND

There are no studies that have directly investigated the incremental reduction in sensory morbidity that lymphoscintigraphy images (LS) and triangulated body marking or other skin marking techniques provide during sentinel lymph node biopsy (SLNB) compared to using only the probe without LS and skin marking or using only dye. However, an indirect assessment of this potential for additional sensory morbidity reduction is possible by extracting morbidity data from studies comparing the morbidity of SLNB to that of axillary lymph node dissection.

METHODS

A literature search yielded 13 articles that had data on sensory morbidity at specific time points on pain, numbness or paresthesia from SLNB that used radiotracer and probe or used only dye as a primary method of finding the sentinel node (SN). Of these, 10 utilized LS, while 3 did not utilize LS. By matching the data in studies not employing LS to the studies that did, comparisons regarding the percentage of patients experiencing pain, numbness/paresthesia after SLNB could be reasonably attempted at a cutoff of 9 months.

RESULTS

In the 7 studies reporting on pain after 9 months (> 9 months) that used LS (1347 patients), 13.8% of patients reported these symptoms, while in the one study that did not use LS (143 patients), 28.7% of patients reported these symptoms at > 9 months (P < 0.0001). In the 6 studies reporting on numbness and/or paresthesia at > 9 months that used LS (601 patients), 12.5% of patients reported these symptoms, while in the 3 studies that did not use LS (229 patients), 23.1% of patients reported these symptoms at > 9 months (P = 0.0002). Similar trends were also noted for all these symptoms at < or = 9 months.

CONCLUSION

Because of variations in techniques and time of assessing morbidity, direct comparisons between studies are difficult. Nevertheless at a minimum, a clear trend is present: having the LS images and skin markings to assist during SLNB appears to yield more favorable morbidity outcomes for the patients compared to performing SLNB with only the probe or performing SLNB with dye alone. These results are extremely pertinent, as the main reason for performing SLNB itself in the first place is to achieve reduced morbidity.