Trial of Lymphoseek in Intraoperative Localization of Lymph Nodes in Breast Cancer and Melanoma

In patients with primary melanoma and breast cancer, lymph node status is often a strong predictor of outcome and influences the course of treatment a patient may follow after surgery. In an effort to reduce the morbidity and costs of detection of lymph node metastases, surgical oncologists have developed a method by which the sentinel lymph node (the first node in a draining basin) is identified intraoperatively and removed. This technique, called sentinel node biopsy, has extremely high negative predictive values for melanoma metastases and breast cancer metastases. The two largest trials for melanoma, Morton, et al (2005) and Rossi, et al (2006), reported false negative rates of 6.3% and 14.7%, respectively. Morton, et al (2006), in perhaps the most mature trial reported to date, showed a false negative rate of 3.4% . There is growing evidence that sentinel node biopsy will have a significant impact on the management of melanoma. Sentinel node biopsy also has extremely high negative predictive values for breast cancer metastases; the false-negative rates range from 0% to 9%. There is growing evidence that sentinel node biopsy will have a significant impact on the management of breast cancer. Although the survival and local recurrence studies have yet to be completed, the technique has emerged into common practice.

Lymphatic mapping with a radiopharmaceutical is a nuclear medicine examination which identifies for the surgeon the first lymph node to receive lymphatic flow from the primary tumor site. This node is removed and analyzed for the presence of malignant cells. By locating the lymph node prior to surgery, a small incision can be used to remove the node and a smaller dissection can be employed. The high negative predictive value of the technique seems to provide an accurate staging procedure and may spare patients who are lymph node negative the morbidity of a complete lymph node dissection. Consequently, staging of melanoma by lymph node mapping and biopsy may be equivalent to regional node dissection without the attendant post surgical morbidity.

An ideal lymph node imaging agent would exhibit rapid clearance from the injection site, rapid uptake and high retention within the first draining lymph node, and low uptake by the remaining lymph nodes. The ideal agent would also have low radiation absorption; high biological safety; convenient, rapid, and stable technetium-99m labeling; and biochemical purity.

Lymphoseek (technetium-99m-labeled diethylenetriamine pentaacetic acid-mannosyl-dextran, [Tc-99m]DTPA-mannosyl-dextran) is a radiotracer that accumulates in lymphatic tissue by binding to a mannose-binding protein that resides on the surface of dendritic cells and macrophages. Lymphoseek is a macromolecule consisting of multiple units of DTPA and mannose, each synthetically attached to a 10 kilodalton dextran backbone. The mannose acts as a substrate for the receptor, and the DTPA serves as a chelating agent for labeling with Tc-99m.

Inclusion criteria

• The patient has provided written informed consent with HIPAA authorization before participating in the study, as has his/her responsible caregiver, if applicable.
• The patient is a candidate for surgical intervention, with lymph node mapping being a part of the surgical plan.
• The patient is at least 18 years of age at the time of consent.
• The patient has an ECOG performance status of Grade 0 - 2 [8].
• The patient has a clinical negative node status at the time of study entry.
• If of child bearing potential, the patient has a negative pregnancy test within 72 hours prior to administration of Lymphoseek, has been surgically sterilized, or has been postmenopausal for at least 1 year.
• The patient is currently not participating in another investigational drug study.

Melanoma Patients

• The patient has a diagnosis of primary melanoma.

Breast Cancer Patients

• The patient has a diagnosis of primary breast cancer.
• Patients with pure ductal carcinoma in situ (DCIS) or non-invasive carcinoma if lymph node biopsy is part of the surgical plan.

Exclusion criteria

• The patient is pregnant or lactating;
• The patient has clinical or radiological evidence of metastatic cancer including palpably abnormal or enlarged lymph nodes (i.e., all patients should be any T,N0,M0);
• The patient has a known hypersensitivity to Lymphazurin or Patent Bleu V.

Melanoma Patients

• The patient has a tumor with a Breslow depth less than 0.75mm.;
• Patients that have had preoperative chemotherapy, immunotherapy or radiation therapy;
• Patients diagnosed with a prior invasive melanoma that would occur on the same body region or potentially draining to the same nodal basin or patients with truncal or extremity primary melanoma who has had a prior breast cancer potentially draining to the same axillary nodal basin;
• Patients who have undergone node basin surgery of any type or radiation to the nodal basin(s) potentially draining the primary melanoma;
• Patients who have undergone a wide excision for their primary melanoma (>1 cm in dimension) or complex reconstruction (rotation, free flap or skin graft of any type).

Breast Cancer Patients

• The patient has bilateral primary breast cancers or multiple tumors within their breast;
• Patients that have had prior surgical procedures such as breast implants, reduction mammoplasty or axillary surgery;
• Patients scheduled for bilateral mastectomy for any reason;
• Patients that have had preoperative radiation therapy to the affected breast or axilla