A Phase II Clinical Trial on Neo-adjuvant Pembrolizumab in Patients With pT3b-T4a/b cN0M0 Melanoma.

The NeoSenti study is a clinical trial exploring whether giving one dose of the immunotherapy drug pembrolizumab before surgery can help improve outcomes for people with high-risk melanoma. Pembrolizumab is a treatment that strengthens the immune system so it can better recognize and attack cancer cells. It is already used after surgery for certain melanoma stages, but this study aims to find out whether giving it earlier-before the sentinel lymph node biopsy-can reduce the chance that melanoma has already spread microscopically. Adults with high-risk primary melanoma who do not show any signs of cancer spread on physical examination or scans may be eligible to participate. Before joining, patients undergo blood tests, a PET/CT scan, an ultrasound of the lymph node area, and a review of their melanoma features. Some patients will also have a Merlin™ genetic test to determine whether their tumor carries a high risk of spreading. Participants who qualify receive a single infusion of pembrolizumab six weeks before their planned surgery. This "pre-surgery" (neoadjuvant) treatment is intended to give the immune system time to attack melanoma cells that may be in the lymph nodes but are too small to detect. About six weeks later, patients undergo surgery, including a sentinel lymph node biopsy-used to check whether melanoma has started to spread-and, if needed, a wide local excision to remove additional tissue around the original melanoma. The results of the surgery determine the next steps. Patients whose cancer is classified as stage IIB, IIC, or III after surgery will continue with standard immunotherapy every six weeks for one year. Patients with stage IB or IIA melanoma will not need additional treatment and will move directly into follow-up care. Regardless of stage, all participants are monitored very closely for five years. This follow-up includes regular physical examinations, blood tests, full-body imaging every four months (PET/CT or whole-body MRI), and optional questionnaires about quality of life and cognitive function. Some patients may also have blood tests that measure tiny amounts of tumor DNA (ctDNA), which might help predict the risk of recurrence.