The benefits of Lymphoseek were shown in two main studies in which 311 patients with breast or skin cancer had their lymph nodes first mapped with Lymphoseek and then with another method involving the use of a dye known as ‘vital blue dye’. The blue dye is used during surgery to stain the lymph nodes so they can be seen and then checked for cancerous tissue. .

In these two studies, doctors were able to detect a higher number of sentinel lymph nodes with Lymphoseek than with the blue dye: almost all of the lymph nodes identified using the blue dye (98% in one study and 100% in the other) were identified using Lymphoseek, while only around 70% and 60%, respectively, of the lymph nodes detected using Lymphoseek were detected with the blue dye.

In a third study in patients with cancer of the head and neck including mouth cancer, Lymphoseek was used to detect sentinel lymph nodes before patients had their lymph nodes removed surgically. Almost all the patients (38 out of 39) with cancerous lymph nodes were identified by Lymphoseek.