Allergic reactions to isosulfan blue during sentinel node biopsy - a common event

Background. Sentinel lymph node (SLN) dissection in the management of high-risk melanoma and other cancers, such as breast cancer, has recently increased in use. The procedure identifies an SLN by intradermal or intraparenchymal injection of an isosulfan blue dye, a radiocolloid, or both around die primary malignancy. Methods. At the time of selective SLN mapping, 3 to 5 mL of isosulfan blue was injected either intradermally or intraparenchymally around the primary malignancy. From October 1997 to May 2000, 267 patients undo-went intraoperative lymphatic mapping with the use of both isosulfan 1 % blue dye and radiocolloid injection. Five cases with adverse reactions to isosulfan blue were reviewed. Results. We report 2 cases of anaphylaxis and 3 cases of "blue hives" after injection with isosulfan blue of 267 patients who had intraoperative lymphatic mapping by the procedure described above. The 2 patients with anaphylaxis experienced cardiovascular collapse, erythema, perioral edema, urticaria, and uvular edema. The blue hives in 3 patients resolved and transformed to blue patches during the course of the procedures. Conclusions. The incidence of allergic reactions in our series was 2.0 %. As physicians expand the role of SLAT mapping, they should consider the use of histamine blockers as prophylaxis and have emergency treatment readily available to treat the life-threatening complication of anaphylactic reaction.