OBJECTIVES : Describe real-world patterns of treatment and locoregional/distant recurrence in patients with non-metastatic melanoma who underwent lymph node surgery (LNS, dissection or lymphadenectomy).

METHODS Adults with non-metastatic melanoma who underwent LNS were identified in Truven MarketScan (Q1/2008 – Q2/2017; n=6,400). LNS test results were not available in Truven, so the study included patients with and without additional positive lymph nodes. Treatment patterns were identified after LNS (median follow-up: 1.9 years). Locoregional and distant recurrence(s) during follow-up were identified based on patterns of melanoma therapy (initiation of new pharmacotherapy, radiotherapy, or new skin excision/LNS) and secondary malignancy diagnoses (excluding 2^nd primary melanoma and non-melanoma cancers) during follow-up.

RESULTS Of 6,400 patients, 219 (3.4%) initiated adjuvant therapy within 3 months of LNS, mostly with interferon-alfa2B (n=206/219, 94.1%; mean duration therapy: 6.4 months); overall, 257/6,400 (4.0%) received adjuvant therapy anytime during follow-up. Other treatments observed during follow-up included: pharmacotherapy for metastatic melanoma (n=32/6,400, 0.5%), radiotherapy (n=186/6,400, 2.9%), new skin excision/LNS (n=1,014/6,400, 15.8%). In addition, 651/6,400 (10.2%) were diagnosed with secondary malignancy and 196/6,400 (3.1%) had a BRAF test. Of 219 patients initiated on adjuvant therapy within 3 months of LNS, 73 (33.3%) experienced recurrence(s) during the follow-up (60 locoregional, 10 distant, 3 both). The first recurrence occurred within a year of the LNS for 51/73 (69.9%), within 2 years for 54/73 (74.0%), and within 3 years for 66/73 (90.4%).

CONCLUSIONS Over Q1/2008 – Q2/2017, few patients with high-risk non-metastatic melanoma managed in real-world practice received adjuvant therapy within 3 months of LNS. Among those patients, one third experienced a recurrence. It remains to be determined how the new generation of adjuvant therapies, such as immune checkpoint inhibitors and targeted agents, will increase the use of adjuvant therapies and reduce the risk of recurrence.