A Study of Lymphoseek® as a Lymphoid Tissue Targeting Agent in Pediatric Patients With Melanoma, Rhabdomyosarcoma, or Other Solid Tumors Who Are Undergoing Lymph Node Mapping

Inclusion Criteria:

* The subject's parent(s)/legal guardian(s) understand(s) and voluntarily signed an informed consent document prior to any study-related assessments/procedures being conducted. Where locally applicable, the subject also understands and voluntarily provides his/her assent prior to any study-related assessments/procedures being conducted
* Subject has been diagnosed with melanoma, rhabdomyosarcoma, or other tumor where tumor resection or biopsy is planned and lymph node mapping is appropriate
* The subject is clinically node negative (cN0) at the time of screening
* Age \< 18 years
* Male subjects of childbearing potential must be willing to use a condom during sexual intercourse and shall not father a child during the course of the study or will practice complete abstinence while on study
* Female subjects of childbearing potential must agree to the use of two physician-approved contraceptive methods simultaneously or practice complete abstinence while on study

Exclusion Criteria:

* The subject has had preoperative radiation therapy
* Has had previous surgery or radiation to node basins that would be involved in the intraoperative lymph node mapping (ILM) procedure
* Has a known allergy to dextran or VBD (if intended to be used)
* Has a history of alcohol abuse or alcohol dependency in the 3 years before study entry, or is an alcoholic or drug addict, as determined by the investigator
* Before the administration of Lymphoseek, has received any radiopharmaceutical within 7 radioactive half-lives of that radiopharmaceutical