Baseline metastatic growth rate is an independent prognostic marker in patients with advanced BRAF V600 mutated melanoma receiving targeted therapy.

BACKGROUND: Targeted therapy (TT) of BRAF V600 mutated unresectable melanoma with inhibitors of the MAPK pathway achieves response rates of up to 76%, but most patients develop secondary resistance. Albeit TT is strikingly efficacious during the first days of treatment, even in advanced cases, long-term survival is highly unlikely, especially in patients with unfavorable baseline characteristics like elevated lactate dehydrogenase (LDH). In patients treated with anti-PD-1 immune checkpoint inhibitors, elevated baseline metastatic growth rate (MGR) was the most important prognostic factor. Here, we aimed at investigating the prognostic impact of MGR in patients with unresectable melanoma receiving TT. METHODS: Clinical records of 242 patients with at least one measurable target lesion (TL) receiving TT at seven skin cancer centers were reviewed. Baseline MGR was determined measuring the largest TL at baseline and at one earlier timepoint. RESULTS: Overall survival (OS) and progression-free survival (PFS) were significantly impaired in patients with an MGR > 3.9 mm/month (median OS: 11.4 vs. 35.5 months, P < 0.0001; median PFS: 4.8 vs. 9.2 months, P < 0.0001). Multivariable analysis of OS and PFS revealed that the prognostic impact of elevated MGR was independent of LDH, presence of brain and liver metastases, tumor burden, and line of treatment. The prognostic significance of elevated MGR was highest in patients with normal LDH. CONCLUSIONS: Baseline MGR is an important independent prognostic marker for OS and PFS in melanoma patients treated with TT. Its implementation in clinical routine is easy and could facilitate the prognostic stratification.

Pretreatment metastatic growth rate determines clinical outcome of advanced melanoma patients treated with anti-PD-1 antibodies: a multicenter cohort study.

BACKGROUND: Checkpoint inhibitors revolutionized the treatment of metastatic melanoma patients. Although tumor burden and lactate dehydrogenase (LDH) are associated with overall survival (OS), the impact of tumor growth kinetics remains elusive and in part contradictory. The aims of this study were to develop a novel simple and rapid method that estimates pretreatment metastatic growth rate (MGR) and to investigate its prognostic impact in melanoma patients treated with antiprogrammed death receptor-1 (PD-1) antibodies. METHODS: MGR was assessed in three independent cohorts of a total of 337 unselected consecutive metastasized stage IIIB-IV melanoma patients (discovery cohort: n=53, confirmation cohort: n=126, independent multicenter validation cohort: n=158). MGR was computed during the pretreatment period before initiation of therapy with anti-PD-1 antibodies nivolumab or pembrolizumab by measuring the increase of the longest diameter of the largest target lesion. Tumor doubling time served as quality control. Kaplan-Meier analysis and univariable as well as multivariable Cox regression were used to examine the prognostic impact of MGR. RESULTS: Pretreatment MGR >3.9 mm/month was associated with impaired OS in the discovery cohort (HR 6.19, 95% CI 2.92 to 13.10, p<0.0001), in the confirmation cohort (HR 3.62, 95% CI 2.19 to 5.98, p<0.0001) and in the independent validation cohort (HR 2.57, 95% CI 1.56 to 4.25, p=0.00023). Prior lines of systemic treatment did not influence the significance of MGR. Importantly, the prognostic impact of MGR was independent of total tumor burden, diameter of the largest metastasis, number of prior lines of systemic treatment, LDH, as well as liver and brain metastasis (discovery and confirmation cohorts: both p<0.0001). Superiority of MGR compared with these variables was confirmed in the independent multicenter validation cohort (HR 2.92, 95% CI 1.62 to 5.26, p=0.00036). CONCLUSIONS: High pretreatment MGR is an independent strong prognostic biomarker associated with unfavorable survival of melanoma patients receiving anti-PD-1 antibodies. Further investigations are warranted to assess the predictive impact of MGR in distinct systemic therapeutic regimens.

Serum S100B and LDH at Baseline and During Therapy Predict the Outcome of Metastatic Melanoma Patients Treated with BRAF Inhibitors.

BACKGROUND: Despite impressive response rates, most patients with advanced melanoma ultimately progress following therapy with B-Raf proto-oncogene (BRAF) inhibitors (BRAFi). Therefore, frequent radiologic assessments are necessary, and reliable serum biomarkers would be beneficial for disease monitoring. OBJECTIVE: This study investigated the ability of lactate dehydrogenase (LDH) and S100 calcium-binding protein B (S100B) to detect response and disease progression during treatment with BRAFi. PATIENTS AND METHODS: Baseline levels of LDH and S100B and repeated measurements during therapy were recorded retrospectively in 191 patients with metastatic melanoma. LDH and S100B levels were compared between distinct time points (baseline, first follow-up visit [FV], best objective response [BR], and progressive disease [PD]). The prognostic ability of the serum biomarkers in relation to disease-specific survival (DSS) was assessed with univariable and multivariable Cox regression analysis. RESULTS: Elevated baseline LDH and S100B correlated with impaired DSS. In contrast with LDH (P = 0.12), S100B levels at FV correlated with response (P = 0.0030). Both markers significantly decreased during the first weeks of BRAFi treatment (LDH, P = 0.00034; S100B, P < 0.0001) and increased between BR and PD (LDH, P = 0.016; S100B, P < 0.0001). Patients with elevated S100B (P = 0.00062) but not with elevated LDH (P = 0.067) at the time point of radiologically confirmed PD showed significantly impaired DSS after PD. Interestingly, DSS after PD differed significantly according to S100B levels determined as early as 8 weeks (median) before PD (P = 0.0024). CONCLUSIONS: LDH and S100B are suitable serum biomarkers during therapy with BRAFi. S100B shows stronger correlation with response and exhibits more accuracy in predicting PD. Close biomarker monitoring with S100B is recommended during treatment with BRAFi to detect PD early.

Prognostic role of gamma-glutamyl transferase in metastatic melanoma patients treated with immune checkpoint inhibitors.

BACKGROUND: Hepatic immune-related adverse events (irAE) including elevated liver function tests (transaminases) occur in 1.4-22.3% of melanoma patients receiving immune checkpoint inhibitors (ICPI) and constitute a potentially serious toxicity that is challenging to treat. In contrast to the liver transaminases alanine aminotransferase (ALT) and aspartate aminotransferase (AST), only little is known about the frequency and impact of gamma-glutamyl transferase (GGT) elevations. METHODS: GGT determined prior to and during therapy of metastatic melanoma patients treated with ICPI were retrospectively assessed in two independent cohorts (PD-1: n = 218, Ipi + Nivo: n = 148). Overall survival (OS) and best objective response were analyzed according to baseline and immune-related GGT (irGGT) elevations during treatment. RESULTS: In multivariate analysis, OS was reduced in patients with elevated baseline GGT (PD-1 group: hazard ratio [HR] 1.76, p = .0073; Ipi + Nivo group: HR 1.77, p = .032). Immune-related GGT elevation was recorded in 17% (PD-1 group) and 38.5% (Ipi + Nivo group). Of these patients, the majority (81 and 68%, respectively) had normal ALT and AST and showed no clinical signs of hepatotoxicity. Patients who experienced irGGT elevation had superior response (PD-1 group: odds ratio [OR] 3.57, p = .00072; Ipi + Nivo group: OR 1.74, p = .12) and OS (PD-1 group: HR 0.37, p = .0016; Ipi + Nivo group: HR 0.33, p = .00050). CONCLUSIONS: The frequency of hepatic irAE is currently underestimated. The addition of the sensitive enzyme GGT to the laboratory panel before and during therapy with ICPI allows to detect two to three times more patients developing hepatic or hepatobiliary toxicity than known so far. Immune-related GGT elevations correlate with response and favorable survival. Precis for use in the Table of Contents The frequency of hepatotoxicity under immune checkpoint blockade is currently underestimated. We suggest the addition of gamma-glutamyl transferase to the laboratory panel in checkpoint inhibitor patients for the detection of hepatobiliary toxicity.