Su Yin

Abstract Introduction: Chemotherapy remains the standard of care for metastatic soft tissue sarcoma (STS), but clinical benefit is modest. Immune checkpoint inhibitors (ICIs), such as anti-programmed cell death 1 (PD-1) and anti-cytotoxic T-lymphocyte antigen 4 (CTLA-4), have transformed cancer treatment, yet their efficacy in STS is variable and largely confined to undifferentiated pleomorphic sarcoma (UPS) and dedifferentiated liposarcoma (LPS).

Melanoma is an aggressive malignancy that arises from melanocytes, specialised pigment-producing cells derived from the neural crest. While melanocytes are primarily found in the skin, they are also present in the eyes, ears and mucosal membranes, and melanoma can develop in any of these locations [1]. Cutaneous melanoma accounts for over 90% of all melanoma diagnoses, while mucosal and uveal melanomas are rare, and comprise less than 5% of cases.

Immune checkpoint inhibitors (ICIs) have significantly extended the survival of patients with advanced melanoma. However, approximately 40% of melanoma patients will have minimal benefit from ICIs and more than 50% will progress on therapy [1]. There is an urgent need to identify robust biomarkers predictive of ICI response to optimize outcomes for each patient.