Patients with early, thin melanoma, such as melanoma in situ, T1a melanoma, or T1b melanoma ≤ 0.5mm, have a very low risk of the cancer spreading to the lymph nodes or other parts of the body. Further, patients with early, thin melanoma have a 97 per cent five-year survival rate, which also indicates a low risk of the cancer spreading to other parts of the body. As such, the performance of sentinel lymph node biopsy is unnecessary.
Additionally, baseline blood tests and radiographic studies (e.g. chest radiographs, CT scans, and PET scans) are not the most accurate tests for the detection of cancer that is spreading because they have high false-positive rates. These tests have only shown benefit when performed as indicated for suspicious signs and symptoms based on the patient’s history and physical exam.