The utility of the VCS clip for creation of vascular access for hemodialysis: long-term results and intraoperative benefits

The purpose of this study was to compare the effectiveness of the VCS vascular clip approximating system for the creation of hemodialysis access fistulas. 173 new vascular accesses were created, 92 prosthetic grafts and 81 autologous fistulas over a 40-month period. 50 sutured and 42 clipped fistulas comprised the prosthetic graft series, and 33 sutured and 48 clipped cases the autologous series. Risk factors associated with access patency were correlated and the primary patencies compared in the suture versus clipped group. A significant improvement in primary patency was noted for the clipped prosthetic group at all time points studied, with a positive trend also noted for clipped autologous fistulae.

CONCLUSIONS

The vascular clipping system (the VCS system) provides both long-term and immediate advantages for vascular access construction. Clips have been used successfully to treat seven consecutive patients with upper extremity arterial steal syndrome without the technical difficulties associated with traditional methods of repair.

Unfiltered sulfur colloid and sentinel node biopsy for breast cancer: technical and kinetic considerations

BACKGROUND

There are few clinical data on technical limitations and radiocolloid kinetics related to sentinel lymph node (SLN) biopsy for breast cancer.

METHODS

In 70 clinical node-negative patients, unfiltered 99mTc sulfur-colloid was injected peritumorally and cutaneous hot spots were mapped with a gamma probe. SLN biopsy was performed followed by axillary lymph node dissection. Missed radioactive nodes (nodes not under hot spots) were removed from axillary lymph node dissection specimens and submitted separately.

RESULTS

At least one hot spot was mapped in 69 patients (98%) and SLNs were retrieved in 62 (89%). No radiolabeled nodes were found in five (7%) and only nodes not under hot spots were retrieved in three patients (4%). Residual nodes not under hot spots were retrieved in 17 patients (24%) in whom at least one SLN specimen had been found. Diffuse radioactivity around the radiocolloid injection site impeded identification of all radiolabeled nodes during SLN biopsy, and was responsible for one of two false negatives (20 node-positive patients; false-negative rate 10%). Hot spot radioactivity, number of radiolabeled nodes, and nodal radioactivity did not change with time interval from radiocolloid injection to surgery (0.75-6.25 hours).

CONCLUSIONS

Although SLN localization rate is high, intraparenchymal injection may predispose to failure of radiocolloid migration, failure to identify SLNs because of high radiation background, and false-negative outcomes. Alternative routes of radiocolloid administration should be explored.

Sentinel lymph node localization in early breast cancer

METHODS

Thirty-two patients with clinical node-negative breast cancer underwent sentinel node localization study as part of a National Cancer Institute-sponsored multicenter trial. Anatomical and histopathologic characteristics of sentinel lymph node (SLN) and a kinetic analysis of nodal uptake were studied. Patients were injected with 1 mCi/4 ml unfiltered 99mTc-sulfur colloid in four divided doses around the palpable lesion or immediately adjacent to the excision cavity if prior biopsy was performed. SLN biopsy was performed 1.5-6 hr (mean = 3 hr) postinjection. Intraoperative localization was performed using a gamma probe. All patients underwent complete axillary dissection.

RESULTS

SLN was identified in 30 of 32 (94%) patients. There were no false-negative SLN biopsies.

CONCLUSION

This study supports the clinical validity of SLN biopsy in breast cancer and confirms that, unlike the blue dye technique, the learning curve with unfiltered 99mTc-sulfur colloid and the gamma detection probe is short, and SLN localization is achievable in over 90% of cases by surgeons with modest experience. The use of unfiltered 99mTc-sulfur colloid (larger particle size) with larger injected volume permits effective localization of SLNs.