This is a non-randomized experimental biomarker study evaluating ctDNA levels in patients with stage IIB/C and stage IIIB/C/D melanoma skin cancer pre and post-surgery

Study participants will complete a ctDNA test within 4 weeks of their planned surgical resection of their melanoma. Within 4 weeks post-surgery another ctDNA test will be completed. During these time points stool samples and diet questionnaires will be collected for biospecimen banking.

The investigators hypothesize that ctDNA levels drawn before and after surgical resection of a primary tumor and either sentinel lymph nodes or clinically involved metastatic lymph nodes will correlate with the presence of sentinel node microscopic metastatic disease and clinically evident nodal metastatic disease. The investigators also predict that approximately 20% of sentinel lymph node negative Stage IIB/IIC patients will have evidence of ctDNA positivity post-surgery.

Primary Objective:

• To assess the feasibility of generating patient specific ctDNA assay from Signatera© test for primary melanoma samples submitted with clinical stage IIB/IIC and stage III melanoma patients.

Secondary Objective(s):

• To investigate serum levels of melanoma ctDNA pre and postoperatively in clinical Stage IIB/C and Stage III melanoma patients.
• To evaluate the relationship of serum ctDNA levels pre-operatively with sentinel lymph node biopsy status in clinical Stage IIB/C patients.
• Evaluate for clearance or persistence of ctDNA levels post complete resection in patients with clinically evident lymph node metastasis (Stage IIIB/C/D).
• Assess feasibility of collection of pre- and post-operative stool samples

INCLUSION CRITERIA:

• Patient must be ≥ 18 years of age.

• Patient must be a surgical candidate with Stage IIB, IIC melanoma or fully resectable Stage III B/C/D cutaneous melanoma.

• Patients with resectable in transit/nodal metastatic disease who have had prior adjuvant or systemic/intralesional therapy can be included provided that the planned resected lesions either progressed or developed while on or after completion of prior treatment. Patients with resectable in transit/nodal metastatic disease who are treated with neoadjuvant therapy prior to resection are also eligible provided that the initial blood and tumor biopsy sample are taken prior to initiation of neoadjuvant therapy.

• Tissue available meeting one of the following criteria:

  1. For patients with Clinical stage II primary tumors that have been biopsied prior to evaluation by the surgeon, or those with stage III tumors that have been partially/fully excised prior to definitive surgery, adequate tissue will be confirmed prior to enrollment to follow Natera's tissue sample collection instructions when selecting the appropriate specimen.

     OR

  2. For patients with bulky lymph nodes involved with clinically evident, biopsy proven metastatic disease, in transit metastasis, or with extensive residual primary tumor present prior to excision, and in the treating surgeon's assessment there will be extensive tumor for evaluation, the patient can be enrolled with tissue adequacy evaluation post resection

• Patient is willing to provide blood samples for Signatera testing as outlined in the study calendar.

• Patient is able to provide informed consent and willing to sign an approved consent form that conforms to federal and institutional guidelines.

EXCLUSION CRITERIA:

• Patient is unable to provide informed consent or is unwilling to sign an approved consent form.
• Patient has other clinically significant disorders that would preclude safe study participation

Patient who have Stage IIB/C or Stage IIB/C/D melanoma skin cancer