Lymphatic mapping and sentinel node biopsy in the management of high-risk melanoma.

We review sentinel lymph node biopsy in patients with high-risk melanoma. This method of selective lymphadenectomy provides valuable staging information about the regional lymphatics without the need of prophylactic complete lymph node dissection. Only patients with micrometastases are candidates for complete lymph node dissection. This avoids, in nearly 85% of patients, the morbidity of the more extensive procedure. In addition, sentinel lymph node-positive patients may qualify for adjuvant therapy protocols. Whether this surgical approach ultimately results in a survival advantage awaits the results of a National Cancer Institute-sponsored national multicenter trial.

Radioguided surgery for the ultrastaging of the patient with melanoma.

PURPOSE: Lymphatic mapping techniques have changed the standard of surgical care for the malignant melanoma population and are being investigated to improve the staging and decrease the morbidity of patients with all types of cancer. This study aimed to describe a combination of techniques and the use of multiple disciplines for accurately staging and treating patients with melanoma. MATERIALS AND METHODS: Over a 4-year period, 595 patients were studied using a protocol consisting of preoperative lymphoscintigraphy using filtered technetium sulfur colloid to define all regional basins at risk for metastatic disease, and intraoperative lymphatic mapping with a vital blue dye and radiocolloid to identify the node in the basin most at risk for metastases (the sentinel lymph node). Detailed pathological exam (serial sectioning, immunohistochemical staining, reverse transcriptase polymerase chain reaction [RT-PCR] analysis) of the sentinel lymph node was used to stage the melanoma patient. RESULTS: A combination of blue dye and radiocolloid intraoperative mapping resulted in a 98% success rate for the identification of the sentinel lymph node. Routine pathological examination identified 73.8% of the metastases. The remainder were detected with serial sectioning (7.8%) and immunohistochemical staining (18.4%). RT-PCR analysis based on a tyrosinase probe has upstaged 47% of the histologic sentinel lymph node-negative population. CONCLUSION: Lymphatic mapping technology provides accurate staging of the melanoma patient, at lower costs for the health care system and a lower morbidity for the patient.

The influence of indomethacin on vasodilator responses to bradykinin and nitroglycerin in the cat.

The effects of indomethacin, a cyclooxygenase inhibitor, on vasodilator responses to bradykinin and nitroglycerin were investigated in the peripheral vascular bed of the anesthetized cat. Intra-arterial injections of bradykinin and nitroglycerin elicited dose-related decreases in mesenteric and hindquarters vascular resistance. Mesenteric vasodilator responses to nitroglycerin in absolute units were unchanged 30 min after administration of indomethacin whereas responses to bradykinin expressed as an absolute mm Hg decrease in perfusion pressure were increased. Indomethacin was also without effect on vasodilator responses to lower doses of nitroglycerin whereas responses to higher doses of nitroglycerin and bradykinin in absolute units were enhanced in the hindquarters vascular bed. Indomethacin increased vascular resistance in the mesenteric and hindquarters vascular beds and decreased systemic vasodepressor responses to the prostaglandin precursor, arachidonic acid. When the increase in (initial value) vascular resistance was taken into account by expressing vasodilator responses on a percent decrease basis, indomethacin only enhanced the vasodilator response to the highest does of bradykinin studies. Result of the present study suggest that products in the cyclooxygenase pathway may serve to maintain the peripheral vascular bed of the cat in a dilated state but that these metabolites do not mediate vasodilator responses to bradykinin. The present data further suggest that products in the cyclooxygenase pathway may play a minor role in modulating the dilator effects of bradykinin in the mesenteric and hindquarters vascular beds of the cat.