Sentinel lymph node biopsy for thick melanoma

The aim of this study was to evaluate the usefulness of sentinel lymph node biopsy (SLNB), a diagnostic procedure, in thick melanoma (thickness ≥ 4mm).

Melanoma is a type of cancer that starts in color-producing cells of the skin. It can grow deep into the inner layers of skin and spread into lymph nodes (tiny, bean-shaped organs that help fight infections). Depending upon how deep a melanoma reaches into the skin layer (also called thickness), treatment is determined.

SLNB is a procedure to find out if the melanoma has reached the lymph nodes.This helps determine the stage of the cancer and also to classify prognosis (estimated outcomes of disease). SLNB is usually recommended when the melanoma is of medium thickness (1-4 mm) and has not yet reached the lymph nodes, based on observation.

Use of SLNB in thick ( ≥ 4mm) melanoma that has not yet reached the lymph nodes remains controversial. Supporters of SLNB believe it can provide improved prognostic information while critics refer to increased risk of spreading of melanoma (metastasis).

The authors aimed to evaluate the benefit of SLNB in thick melanoma that has not spread to the lymph nodes.

Overall, 571 patients with average melanoma thickness of 6.2 mm and no distant metastases were enrolled in this study. Of these,  SLNB was performed in 412 patients, 46 patients had cancer in the lymph nodes at the start of the study and the rest did not undergo SLNB.

The authors concluded that patients with thick melanoma and negative SLNB exhibited improved overall survival, disease-specific survival and recurrence-free survival compared to patients with positive SLNB.  Therefore, patients with thick, clinically lymph-node negative melanoma should consider SLNB in order to determine the most appropriate treatment strategy. 

You may consider talking to your doctor about SLNB if the melanoma is thick ( > 4 mm) and clinically lymph node-negative.