Treatment Approaches for Melanomas That Relapse After Adjuvant or Neoadjuvant Therapy

Relapse-free survival with adjuvant dabrafenib/trametinib therapy after relapse on a prior adjuvant CPI in BRAF V600-mutated stage III/IV melanoma

BACKGROUND

In BRAF-mutated high-risk melanoma, targeted therapy (BRAF/MEK inhibitors) and checkpoint inhibitor (CPI) immunotherapy have durable benefits as first-line (1L) adjuvant therapy. Based on differing action mechanisms of BRAF/MEK inhibitors and CPI immunotherapies, there is interest in evaluating the activity of 2L adjuvant targeted therapy in decreasing the risk of subsequent recurrence after repeat resection following relapse on/after 1L adjuvant CPI.

PATIENTS AND METHODS

This was a retrospective review of BRAF V600-mutated resected stage III/IV melanoma patients in the United States, Australia, and The Netherlands who received 1L adjuvant CPI immunotherapy, relapsed locoregionally/distantly, were again resected to no evidence of disease, and received dabrafenib/trametinib (dab/tram) as 2L adjuvant therapy. The primary endpoint was relapse-free survival (RFS) from initiation of 2L adjuvant dab/tram (RFS-2), analyzed via Kaplan-Meier methods.

RESULTS

Thirty-eight patients were included (median age 50 years, 63% male, 87% stage III, median follow-up 19 months from 2L dab/tram initiation). Median dab/tram duration was 10.1 months (range: 1 day-22.7 months), with half discontinuing due to progression or adverse events. Median (95% CI) RFS-2 was 18.9 (14.9-28.1) months, with 91%, 81%, and 58% remaining relapse-free at 6, 12, and 18 months, respectively. Most patients remained distant metastasis-free at 6, 12, and 18 months (97%, 85%, and 71%, respectively). Two patients were deceased at the last follow-up, with 97% alive at 18 months.

CONCLUSIONS

Over 80% of patients remained relapse- and metastasis-free at 12 months after 2L dab/tram initiation, with only 2 deaths observed. Dab/tram appears to have activity in the 2L adjuvant setting, although more follow-up is required.

Nature and management of melanoma recurrences following adjuvant anti-PD-1 based therapy

INTRODUCTION

Approximately 50 % of resected stage II-IV melanoma patients develop recurrent disease by 5 years despite adjuvant anti-PD-1 therapy. Data to define best management of recurrences is lacking.

METHODS

This was a multicentre, international, retrospective cohort study. Patients with resected stage II-IV melanoma who commenced adjuvant anti-PD-1-based therapy before January 2022 and later recurred were identified. Data on demographics, disease characteristics, recurrence patterns, management and outcomes were collected.

RESULTS

711 patients from 17 sites were included. Median age was 60 [range 16-92], 64 % were male, 2 % stage II, 91 % were stage III, 7 % stage IV. Median time to recurrence was 6.2 months (0-68.5) and median follow up time from recurrence was 19.8 months (range 0.2-73.1). 63 % recurred on anti-PD-1 therapy, 36 % off therapy [3 % < 6 months, 33 % > 6 months]. Initial recurrences were locoregional (LR) alone in 44 %, distant alone (DR) in 43 %, and 11 % in both sites. LR recurrences were managed with local therapy, alone (62 %) or with "second adjuvant" anti-PD-1 (14 %) or BRAF/MEK therapy (23 %); 12 m RFS2 was 25 %, 29 % and 69 % respectively (p = 0.0045). Definitive systemic therapy at first recurrence was given in 16 % LR and 86 % DR, with best outcomes for anti-CTLA4 + anti-PD-1 and trial combinations (24 m PFS 63 % and 69 %, respectively). The 24 m OS for the entire cohort was 65 %.

CONCLUSION

Most recurrences following adjuvant anti-PD-1 based therapy occur early and while still on drug. Outcomes are poor, regardless of site, timing of recurrence, and subsequent treatment.

Real-Life Outcomes of Adjuvant Targeted Therapy and Anti-PD1 Agents in Stage III/IV Resected Melanoma

This study was carried out at the Dermatologic Clinic of the University of Turin, Italy, to assess the effectiveness and safety of adjuvant therapy in patients who received either targeted therapy (TT: dabrafenib + trametinib) or immunotherapy (IT: nivolumab or pembrolizumab) for up to 12 months. A total of 163 patients participated, including 147 with stage III and 19 with stage IV with no evidence of disease. The primary outcomes were relapse-free survival (RFS), distant metastasis-free survival (DMFS), and overall survival (OS). At 48 months, both TT and IT approaches yielded comparable outcomes in terms of RFS (55.6-55.4%, p = 0.532), DMFS (58.2-59.8%, p = 0.761), and OS (62.4-69.5%, p = 0.889). Whilst temporary therapy suspension was more common among TT-treated patients compared to IT-treated individuals, therapy discontinuation due to adverse events occurred at comparable rates in both groups. Predictors of relapse included mitoses, lymphovascular invasion, ulceration, and positive sentinel lymph nodes. Overall, the proportion of BRAF-mutated patients receiving IT stood at 7.4%, lower than what was observed in clinical trials.

Oncogenic LINC00698 suppresses apoptosis of melanoma stem cells to promote tumorigenesis via LINC00698-miR-3132-TCF7/hnRNPM axis

Melanoma progression depends on melanoma stem cells (MSCs), which are distinguished by the distinct dysregulated genes. As the key factors in the dysregulation of genes, long non-coding RNAs (lncRNAs) take great effects on MSCs. However, the underlying mechanism of lncRNAs in MSCs has not been extensively characterized. To address the roles of lncRNAs in MSCs, LINC00698 was characterized in this study. The results revealed that LINC00698 was upregulated in MSCs, showing its important role in MSCs. The further data indicated that the LINC00698 silencing triggered cell cycle arrest in the G0/G1 phase and apoptosis of MSCs. LINC00698 could directly interact with miR-3132 to upregulate the expression of TCF7, which was required for sustaining the stemness and the tumorigenic potency of MSCs. At the same time, LINC00698 could bind to the hnRNPM protein to enhance the protein stability, thus suppressing apoptosis and promoting the stemness of MSCs. Furthermore, the in vivo data demonstrated that LINC00698 was essential for tumorigenesis of MSCs via the LINC00698-miR-3132-TCF7/hnRNPM axis. Therefore, our findings contributed novel insights into the underlying mechanism of melanoma progression.

Real-world outcomes of patients with resected stage III melanoma treated with adjuvant therapies

BACKGROUND

Both immunotherapy (IO) and targeted therapy (TT) are used as adjuvant (adj) treatment for stage III melanoma, however, data describing real-world outcomes are limited. In addition, a significant proportion of patients relapse, for whom best management is unclear. The aim of our study was to assess the efficacy, and safety of adj anti-PD1 IO and TT in a real-world cohort of patients with resected stage III melanoma, and further delineate patterns of recurrence and treatment strategies.

METHODS

We retrospectively analyzed 130 patients who received adj therapy (100 anti-PD1 IO and 30 TT).

RESULTS

At a median follow-up of 30 months, median relapse-free survival (RFS) was 24.6 (95% CI, 17-not reached [NR]) versus 64 (95% CI, 29.5-NR) months for the TT and IO groups, respectively (p = 0.26). Median overall survival (OS) was NR for either subgroup. At data cutoff, 77% and 82% of patients in TT and IO arms were alive. A higher number of grade ≥3 treatment-related adverse events (AEs) were noted in the IO group (11% vs. 3%), however, a higher proportion of patients permanently discontinued adj therapy in the TT group (43% vs. 11%) due to toxicity. Strategies at relapse and outcomes were variable based on location and timing of recurrence. A significant number of patients who relapsed after adj IO received a second round of IO. Among them, patients who were off adj IO at relapse had superior second median RFS (mRFS2), compared to those who relapsed while on adj IO; mRFS2 was NR versus 5.1 months (95% CI, 2.5-NR), respectively, p = 0.02.

CONCLUSION

In summary, both TT and IO yielded prolonged RFS in a real-world setting, however, longer follow-up is needed to determine any potential OS benefit. Adj therapy, particularly TT, may not be as well tolerated as suggested in clinical trials, with lower completion rates (59% vs. 74%) in a real-life setting. Overall, patients who relapse during adj therapy have poor outcomes, while patients who relapse after discontinuation of adj IO therapy appear to benefit from IO re-treatment.

Anti-Melanoma Effects of Miconazole: Investigating the Mitochondria Involvement

Miconazole is an antimycotic drug showing anti-cancer effects in several cancers. However, little is known on its effects in melanoma. A375 and SK-MEL-28 human melanoma cell lines were exposed to miconazole and clotrimazole (up to 100 mM). Proliferation, viability with MTT assay and vascular mimicry were assayed at 24 h treatment. Molecular effects were measured at 6 h, namely, ATP-, ROS-release and mitochondria-related cytofluorescence. A metabolomic profile was also investigated at 6 h treatment. Carnitine was one of the most affected metabolites; therefore, the expression of 29 genes involved in carnitine metabolism was investigated in the public platform GEPIA2 on 461 melanoma patients and 558 controls. After 24 h treatments, miconazole and clotrimazole strongly and significantly inhibited proliferation in the presence of 10% serum on either melanoma cell lines; they also strongly reduced viability and vascular mimicry. After 6 h treatment, ATP reduction and ROS increase were observed, as well as a significant reduction in mitochondria-related fluorescence. Further, in A375, miconazole strongly and significantly altered expression of several metabolites including carnitines, phosphatidyl-cholines, all amino acids and several other small molecules, mostly metabolized in mitochondria. The expression of 12 genes involved in carnitine metabolism was found significantly modified in melanoma patients, 6 showing a significant impact on patients' survival. Finally, miconazole antiproliferation activity on A375 was found completely abrogated in the presence of carnitine, supporting a specific role of carnitine in melanoma protection toward miconazole effect, and was significantly reversed in the presence of caspases inhibitors such as ZVAD-FMK and Ac-DEVD-CHO, and a clear pro-apoptotic effect was observed in miconazole-treated cells, by FACS analysis of Annexin V-FITC stained cells. Miconazole strongly affects proliferation and other biological features in two human melanoma cell lines, as well as mitochondria-related functions such as ATP- and ROS-release, and the expression of several metabolites is largely dependent on mitochondria function. Miconazole, likely acting via carnitine and mitochondria-dependent apoptosis, is therefore suggested as a candidate for further investigations in melanoma treatments.

Final 5-Year Follow-Up Results Evaluating Neoadjuvant Talimogene Laherparepvec Plus Surgery in Advanced Melanoma: A Randomized Clinical Trial

This randomized clinical trial presents the final 5-year follow-up results of neoadjuvant talimogene laherparepvec (T-VEC) plus surgery in patients with advanced melanoma.

Efficacy and Safety of Rechallenge with BRAF/MEK Inhibitors in Advanced Melanoma Patients: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis aims to evaluate the efficacy and safety of rechallenging advanced melanoma patients with BRAFi/MEKi. Seven studies, accounting for 400 patients, were included. Most patients received immunotherapy before the rechallenge, and 79% underwent rechallenge with the combination of BRAFi/MEKi. We found a median progression-free survival of 5 months and overall survival of 9.8 months. The one-year survival rate was 42.63%. Regarding response, ORR was 34% and DCR 65%. There were no new or unexpected safety concerns. Rechallenge with BRAFi/MEKi can improve outcomes in advanced melanoma patients with refractory disease. These findings have significant implications for clinical practice, particularly in the setting of progressive disease in later lines and limited treatment options.

p53 Family in Resistance to Targeted Therapy of Melanoma

Metastatic melanoma is one of the most aggressive tumors, with frequent mutations affecting components of the MAPK pathway, mainly protein kinase BRAF. Despite promising initial response to BRAF inhibitors, melanoma progresses due to development of resistance. In addition to frequent reactivation of MAPK or activation of PI3K/AKT signaling pathways, recently, the p53 pathway has been shown to contribute to acquired resistance to targeted MAPK inhibitor therapy. Canonical tumor suppressor p53 is inactivated in melanoma by diverse mechanisms. The TP53 gene and two other family members, TP63 and TP73, encode numerous protein isoforms that exhibit diverse functions during tumorigenesis. The p53 family isoforms can be produced by usage of alternative promoters and/or splicing on the C- and N-terminus. Various p53 family isoforms are expressed in melanoma cell lines and tumor samples, and several of them have already shown to have specific functions in melanoma, affecting proliferation, survival, metastatic potential, invasion, migration, and response to therapy. Of special interest are p53 family isoforms with increased expression and direct involvement in acquired resistance to MAPK inhibitors in melanoma cells, implying that modulating their expression or targeting their functional pathways could be a potential therapeutic strategy to overcome resistance to MAPK inhibitors in melanoma.

Adjuvant PD-1 and PD-L1 Inhibitors and Relapse-Free Survival in Cancer Patients: The MOUSEION-04 Study

BACKGROUND

Adjuvant treatment has always been a cornerstone in the therapeutic approach of many cancers, considering its role in reducing the risk of relapse and, in some cases, increasing overall survival. Adjuvant immune checkpoint inhibitors have been tested in different malignancies.

METHODS

We performed a meta-analysis aimed to explore the impact of adjuvant PD-1 and PD-L1 inhibitors on relapse-free survival (RFS) in cancer patients enrolled in randomized controlled clinical trials. We retrieved all phase III trials published from 15 June 2008 to 15 May 2022, evaluating PD-1/PD-L1 inhibitors monotherapy as an adjuvant treatment by searching on EMBASE, Cochrane Library, and PubMed/ Medline, and international oncological meetings' abstracts. The outcome of interest was RFS. We also performed subgroup analyses focused on age and gender.

RESULTS

Overall, 8 studies, involving more than 6000 patients, were included in the analysis. The pooled results highlighted that the use of adjuvant PD-1/PD-L1 inhibitors may reduce the risk of relapse compared to control treatments (hazard ratio, 0.72; 95% confidence intervals, 0.67-0.78). In addition, the subgroup analyses observed that this benefit was consistent in different patient populations, including male, female, younger, and older patients.

CONCLUSIONS

Adjuvant anti-PD-1/PD-L1 treatment is associated with an increased RFS in the overall population and in subgroups divided according to age and gender.