Evaluation Of Mobile Gamma Camera Imaging For Sentinel Node Biopsy In Melanoma

Inclusion Criteria:

* Patients with a diagnosis of melanoma for whom a sentinel node biopsy is planned as part of standard surgical management of the melanoma. Patients may have more than one primary lesion.
* Patients with other malignancies may be included in this study, but the primary focus of this study is on melanoma, and data analysis of the melanoma patients will be independent of patients for whom sentinel node biopsy is done for other malignancies. It may also include patients for whom the diagnosis of melanoma is not certain but sentinel node biopsy is planned as part of the standard management (e.g.: severely atypical melanocytic neoplasms of uncertain malignant potential).
* All patients must have the ability and willingness to give informed consent.
* Age 18 years or older at the time of study entry. (Younger patients are excluded for simplicity since this avoids the requirement for separate consent documents, this is just a pilot study, and patients under age 18 are uncommon enough that they would not be likely to be enrolled in this small pilot study)

Exclusion Criteria:

* Participants in whom there is a medical contraindication or potential problem in complying with the requirements of the protocol in the opinion of the investigator
* Patients receiving there technetium injection more than 12 hours prior to their scheduled surgery