This was a retrospective cohort study using the PharMetrics database. The analysis was conducted using the most recent 5 years of data from the database, January 1, 2015, to October 30, 2020. Included patients were followed for outcome evaluation from the index date (first prescription of treatment, immunotherapy [IO], or targeted therapy [TT] following diagnosis of non-metastatic malignant melanoma and evidence of first lymph node resection), until the first occurrence or end of continuous eligibility or end of the study period.

Inclusion Criteria

• Patients with at least one diagnosis of malignant melanoma of skin anytime from the start of data collection until the start of study period.
• Patients with a procedure of first lymph node dissection or nodal basin ultrasound surveillance, per the National Comprehensive Cancer Network (NCCN) guidelines version 2.2020. The first lymph node dissection / nodal basin ultrasound surveillance signified that the patient was eligible to receive systemic treatment as adjuvant therapy.
• The first lymph node dissection or nodal basin ultrasound surveillance (index adjuvant date) must have had a diagnosis of malignant melanoma of skin within 6 months, to ensure that the dissection was related to melanoma.
• Patients with at least pharmacy or medical claim for the study drugs within 1 year on and after index date. The index date was the date of first prescription of study drug, IO (i.e., nivolumab, ipilimumab + nivolumab, pembrolizumab) or dabrafenib + trametinib.
• At least 18 years of age at the time of adjuvant treatment initiation.
• Patients with at least 6 months of continuous enrollment prior to the index date.
• Patients with at least 6 months of continuous enrollment after the index date.
• If necessary, there were additional criteria of absence of secondary malignancy (including metastatic site).

Exclusion Criteria

• Patients with a diagnosis of non-melanoma primary malignancy during the 6 months pre-index period.
• Patients with chemotherapy or interferon alpha before index date.
• Patients with pregnancy any time during the study period.

This was a retrospective, noninterventional cohort study