Prognostic significance of the CP-GEP assay combining clinicopathologic factors and gene expression profiling in patients (pts) with AJCC v8 stage I/II cutaneous melanoma (CM)

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Background: AJCC v8 includes Breslow thickness and ulceration to subdivide stage I and II CM pts into risk groups. In light of the results from adjuvant therapy in stage II CM, it has been discussed that pts’ follow-up and eventually treatment should consider additional markers, namely CP-GEP, to further refine the risk classification provided by the AJCC v8. The aim of this single center study was to clinically validate a prognostic CP-GEP-based risk score for stage I/II CMs combining Breslow, age and the expression of 8 genes SERPINE2, GDF15, ITGB3, CXCL8, LOXL4, TGFBR1, PLAT and MLANA. Methods: All obtainable formalin-fixed paraffin-embedded primaries of stage I/II CMs with negative sentinel lymph node (SLN) from the Central Malignant Melanoma Registry of Germany diagnosed between 2000-2017 and archived in Tuebingen were included. Study hypothesis and protocol were prospectively formulated. Tumors were analyzed blinded to clinical outcome. Quantitative reverse transcription polymerase chain reaction of the 8 genes was performed and combined with age and tumor thickness to define CP-GEP low- vs. high-score groups. Relapse-free survival (RFS), distant metastasis free survival (DMFS) and overall survival (OS) were evaluated using Kaplan-Meier curves. CP-GEP score performance was tested using multivariate Cox regression adjusted for tumor thickness, ulceration and age. Results: We included 543 pts with Stage IA (n=78); IB (n=223); IIA (n= 123); IIB (n=73); IIC (n=46). 43% were females, median Breslow was 1.7mm and 25% of tumors had ulceration. The median follow-up was 78 months (IQR 47-116). 311 (57%) patients had a high-risk CP-GEP score. The 5-y RFS rate was 71% and 92% (HR 4.2; p<0.001), the 5-y DMFS rate was 86% and 96% (HR 4.35; p<0.001) and the 5-y OS was 85% and 95% (HR 3.2; p=0.001), respectively for high and low-risk CP-GEP score. In multivariate Cox regression analysis for RFS including Breslow thickness, ulceration and age, contribution of CP-GEP score remained independently significant (HR 2.75; p=0.0008) compared to age (HR 1.03; p<0.0007), Breslow (HR 1.21; p<0.0001) and ulceration (HR 1.37; p=0.1694). Conclusions: CP-GEP risk score is a non-invasive and independent prognostic model for risk of relapse in stage I/II melanoma validated in this study. It identifies SLN negative pts at high risk of relapse and should be considered for complementing AJCC classification and for inclusion in future clinical trials.[Table: see text]

Salvage therapy after failure from anti-PD-1 single agent treatment: A Study by the German ADOReg melanoma registry

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Background: In melanoma, potential benefits of therapies after PD-1 inhibitor failure, including those BRAF positive patients who have already received combined BRAF-/MEK inhibitors before anti PD-1 are poorly defined. We therefore analyzed the treatment patterns and outcome of systemic therapies for patients after anti-PD-1 failure. Methods: From the ADOReg registry, patients fulfilling the following inclusion criteria were consecutively included until a number of 200 cases was reached. 1) Ipilimumab naive patients with unresectable metastatic cutaneous or mucosal melanoma. 2) Failure from treatment with a single agent anti PD-1 antibody. 3) Known BRAF status and, in case of BRAF-V600 mutation, BRAF-/MEK-inhibitor treatment prior to anti PD-1 treatment. 4) Consecutive systemic treatment started within a maximum of 6 months after anti PD-1 failure. Objectives: Rate of objective remissions (ORR), disease control (DCR), survival (OS), tolerability and disease patterns correlated to the use of different treatments after PD-1 treatment failure in real-life conditions in Germany. Results: In total 23.5 % of the patients received ipilimumab single agent, 38.5 % received the combination of ipilimumab and nivolumab (Ipi/Nivo), and the remaining various regimens. (Table) Ipi/Nivo resulted in an ORR significantly higher than for Ipi alone (p=0.02). In 18 patients receiving BRAF-/MEK inhibitor re-challenge, ORR was comparable to Ipi/Nivo. Conventional Chemotherapy was still in frequent use (dacarbazine n =33; other n=17), but response rates were low (ORR 6%). Some remission were also achieved by use of talimogene laherparepvec (n=2 out of 4). Conclusions: Treatment patterns of patients after anti-PD-1 failure differ remarkably. Although lower than reported in treatment naive patients, the combination of Ipilimumab and Nivolumab appeared favorable as compared to all other regimens, except for BRAF-/MEK inhibitor re-challenge which produced similar remission rates. Still, chemotherapies including dacarbazine are in clinical practice, though giving only poor outcome. [Table: see text]

Evaluation of the Melanoma Tumor Burden Score (MTBS) in a real-world setting

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Background: Clinical cancer registration is increasingly important for healthcare delivery and outcome research in oncology. As compared to clinical trial data, information from clinical routine is often limited regarding the granularity and quality of measures for individual tumor load and distribution. Methods: In an effort to implement a robust and useful measure of tumor burden for patients with metastatic melanoma in a German national skin cancer registry (ADOReg) we evaluated the melanoma tumor burden score (MTBS), originally developed for analyzing chemotherapy data in melanoma patients. The MTBS contains a simple categorization of size, number an distribution of metastatic lesions in individual patients. It is aimed at being used on routine radiologic report allowing for a certain level of uncertainty and imprecise quantification of metastatic lesions. Basically, the lesions are categorized per affected organ with respect to number (solitary, few, multiple) and size (≤1cm, >1- 5cm, >5cm). For evaluation of prognostic significance the summary score was calculated and included in univariate and multivariate survival analysis. We performed extensive sensitivity analyses for a variety of different model settings. Results: In the primary analysis set we re-evaluated 898 radiologic reports in a total of 235 various chemotherapies in n=128 stage IV melanoma patients. The confirmatory data sets consisted of n=384 stage IV melanoma patients with various treatments including chemotherapy, BRAF inhibitor treatment, and immune checkpoint blockade. MTBS categorization could be applied on routine radiologic reports in the majority of cases (95.7 %). In a multivariate model MTBS remained significantly correlated with outcome when adjusted for age, sex, LDH, and number of metastatic sites. Moreover, change in MTBS correlated to a formal response evaluation according to RECIST. Conclusions: The MTBS appears to be a promising tool for meaninful quantification of metastatic tumor load in metastatic melanoma for real life data collection like in clinical cancer registries. [Table: see text]