Eligible patients who provided written informed consent were randomly assigned to undergo completion lymph-node dissection or nodal observation. These patients were 18 to 75 years of age and had clinically localized cutaneous melanoma, an Eastern Cooperative Oncology Group performance status of 0 or 1 (on a 5-point scale, with 0 indicating an absence of disability and higher numbers indicating greater disability), a non–melanoma-related life expectancy of 10 years or more, and a tumor-positive sentinel node. The trial was opened before the universal application of registration. The trial opened in December 2004 and was registered at Clinicaltrials.gov on February 27, 2006. At the time of registration, 119 patients had been enrolled in the trial.
Randomization was performed in a 1:1 ratio with the use of a permuted-block design, which was stratified according to Breslow thickness, ulceration, method of metastasis detection (standard pathological assessment or RT-PCR assay), and enrollment at an MSLT-I center. Patients who were assigned to the observation group were monitored by means of clinical examination every 4 months during the first 2 years, every 6 months during years 3 through 5, and then annually. Nodal ultrasonographic assessment of the sentinel-node basin occurred at each visit for the first 5 years; findings were considered to be abnormal on the basis of a length:depth ratio of less than 2, a hypoechoic center, an absence of hilar vessels, or focal nodularity with increased vascularity. Follow-up of the dissection group involved the same schedule, but without protocol-mandated nodal ultrasonography.
Randomization was performed in a 1:1 ratio with the use of a permuted-block design, which was stratified according to Breslow thickness, ulceration, method of metastasis detection (standard pathological assessment or RT-PCR assay), and enrollment at an MSLT-I center. Patients who were assigned to the observation group were monitored by means of clinical examination every 4 months during the first 2 years, every 6 months during years 3 through 5, and then annually. Nodal ultrasonographic assessment of the sentinel-node basin occurred at each visit for the first 5 years; findings were considered to be abnormal on the basis of a length:depth ratio of less than 2, a hypoechoic center, an absence of hilar vessels, or focal nodularity with increased vascularity. Follow-up of the dissection group involved the same schedule, but without protocol-mandated nodal ultrasonography.
