Management of Melanoma: A European Perspective

Interferon alpha for the adjuvant treatment of cutaneous melanoma

BACKGROUND

Interferon alpha is the only agent approved for the postoperative adjuvant treatment of high-risk cutaneous melanoma. However, the survival advantage associated with this treatment is unclear, especially in terms of overall survival. Thus, adjuvant interferon is not universally considered a gold standard treatment by all oncologists.

OBJECTIVES

To assess the disease-free survival and overall survival effects of interferon alpha as adjuvant treatment for people with high-risk cutaneous melanoma.

SEARCH METHODS

We searched the following databases up to August 2012: the Cochrane Skin Group Specialised Register, CENTRAL in The Cochrane Library (2012, issue 8), MEDLINE (from 2005), EMBASE (from 2010), AMED (from 1985), and LILACS (from 1982). We also searched trials databases in 2011, and proceedings of the ASCO annual meeting from 2000 to 2011. We checked the reference lists of selected articles for further references to relevant trials.

SELECTION CRITERIA

We included only randomised controlled trials (RCTs) comparing interferon alpha to observation (or any other treatment) for the postoperative (adjuvant) treatment of patients with high-risk skin melanoma, that is, people with regional lymph node metastasis (American Joint Committee on Cancer (AJCC) TNM (tumour, lymph node, metastasis) stage III) undergoing radical lymph node dissection, or people without nodal disease but with primary tumour thickness greater than 1 mm (AJCC TNM stage II).

DATA COLLECTION AND ANALYSIS

Two authors extracted data, and a third author independently verified the extracted data. The main outcome measure was the hazard ratio (HR), which is the ratio of the risk of the event occurring in the treatment arm (adjuvant interferon) compared to the control arm (no adjuvant interferon). The survival data were either entered directly into Review Manager (RevMan) or extrapolated from Kaplan-Meier plots and then entered into RevMan. Based on the presence of between-study heterogeneity, we applied a fixed-effect or random-effects model for calculating the pooled estimates of treatment efficacy.

MAIN RESULTS

Eighteen RCTs enrolling a total of 10,499 participants were eligible for the review. The results from 17 of 18 of these RCTs, published between 1995 and 2011, were suitable for meta-analysis and allowed us to quantify the therapeutic efficacy of interferon in terms of disease-free survival (17 trials) and overall survival (15 trials). Adjuvant interferon was associated with significantly improved disease-free survival (HR (hazard ratio) = 0.83; 95% CI (confidence interval) 0.78 to 0.87, P value < 0.00001) and overall survival (HR = 0.91; 95% CI 0.85 to 0.97; P value = 0.003). We detected no significant between-study heterogeneity (disease-free survival: I² statistic = 16%, Q-test P value = 0.27; overall survival: I² statistic = 6%; Q-test P value = 0.38).Considering that the 5-year overall survival rate for TNM stage II-III cutaneous melanoma is 60%, the number needed to treat (NNT) is 35 participants (95% CI = 21 to 108 participants) in order to prevent 1 death. The results of subgroup analysis failed to answer the question of whether some treatment features (i.e. dosage, duration) might have an impact on interferon efficacy or whether some participant subgroups (i.e. with or without lymph node positivity) might benefit differently from interferon adjuvant treatment.Grade 3 and 4 toxicity was observed in a minority of participants: In some trials, no-one had fever or fatigue of Grade 3 severity, but in other trials, up to 8% had fever and up to 23% had fatigue of Grade 3 severity. Less than 1% of participants had fever and fatigue of Grade 4 severity. Although it impaired quality of life, toxicity disappeared after treatment discontinuation.

AUTHORS' CONCLUSIONS

The results of this meta-analysis support the therapeutic efficacy of adjuvant interferon alpha for the treatment of people with high-risk (AJCC TNM stage II-III) cutaneous melanoma in terms of both disease-free survival and, though to a lower extent, overall survival. Interferon is also valid as a reference treatment in RCTs investigating new therapeutic agents for the adjuvant treatment of this participant population. Further investigation is required to select people who are most likely to benefit from this treatment.

Novel immunotherapeutic agents and small molecule antagonists of signalling kinases for the treatment of metastatic melanoma

Melanoma incidence is increasing annually and over 40,000 die of this disease each year worldwide. In this review, we discuss the rationale and recent trial results of several novel immunotherapeutic approaches and small molecule inhibitors of signalling kinases. Ipilimumab is a humanized anti-CTLA4 antibody that has been proven to increase the median overall survival of large cohorts of patients with unresectable melanoma in two phase III trials. OncoVEX(GM-CSF) is an oncolytic herpes simplex virus-1 recombined with granulocyte-macrophage colony-stimulating factor that has demonstrated durable objective responses in a phase II trial. Tumour-infiltrating lymphocytes given after lymphocyte depletion and followed by high-dose interleukin (IL)-2 yield durable complete responses in a significant percentage of melanoma patients. Lastly, denileukin diftitox, a fusion of IL-2 and diphtheria toxin, was recently observed to deplete regulatory T cells and cause durable partial responses, particularly in chemo/immune-naïve patients. These agents are enabling the rational design of novel combination trials to simultaneously increase antigen presentation, deplete regulatory T cells and block immune check-points in order to activate melanoma antigen-specific immunity. Although melanoma metastases have been found to contain thousands of mutations, the V600E BRAF mutation is clearly a driver of the neoplastic phenotype and is present in 40-60% of melanomas. Two separate small molecule antagonists of B-Raf have been found to yield very high partial response rates in metastatic melanoma, and the B-Raf inhibitor, vemurafenib (PLX4032), was recently observed to increase median overall survival in an interim analysis. However, B-Raf inhibitor resistance through up-regulation or activating mutations of alternative oncogenic signalling receptors and enzymes is proving to be a major challenge. Inhibitors of c-Kit and mitogen-activated protein kinase (MEK) have also been found to have activity against melanomas and MEK inhibitors are now being examined as a strategy to overcome B-Raf inhibitor resistance. In summary, these studies reveal that, for the first time, several immunotherapeutic and targeted agents are yielding dramatic clinical responses and improvements in overall survival in patients with unresectable stage III and IV melanoma.

Diagnostic and therapeutic imaging for cancer: therapeutic considerations and future directions

As cancer treatment cost soar and the mantra for "personalized medicine" grows louder, we will increasingly be searching for solutions to these diametrically opposed forces. In this review we highlight several exciting novel imaging strategies including MRI, CT, PET SPECT, sentinel node, and ultrasound imaging that hold great promise for improving outcomes through detection of lymph node involvement. We provide clinical data that demonstrate how these evolving strategies have the potential to transform treatment paradigms.

Radio-guided ultrasound lymph node localization: feasibility of a new technique for localizing and excising nonpalpable lymph nodes ultrasound suspicious for melanoma metastases

Identification of lymph nodes suspicious for metastases is crucial in melanoma patients during the follow-up. We propose a procedure called radio-guided ultrasound lymph node localization (RULL) for melanoma patients with ultrasound (US) suspicious, not palpable, lymph nodes. The aim of this study was to evaluate the feasibility of this technique, and to assess the efficacy of this new method. RULL was applied in 12 consecutive melanoma patients with non-palpable lymph nodes found suspicious for metastases during US follow-up. Macro-aggregates of human serum albumin labelled with diluted technetium-99m were injected into the suspected lymph node under US guidance and followed by a scintigraphy. The surgical treatment was carried out with the support of hand-held gamma-probe used for sentinel node biopsy. The tracer was correctly positioned in all 12 patients. Pathological examination revealed seven patients with metastatic lymph nodes, four with no metastatic lymph node, one patient with Hodgkin disease. No surgical complications were described. In conclusion, RULL may integrate the standard ultrasound-guided fine-needle aspiration to improve the diagnostic accuracy on US suspicious nodes and might replace the more logistically complicated wire identification or less accurate cutaneous marker identification of these nodes. Sensibility and specificity of this approach should be defined through a large multicentric study.

Interferon alpha adjuvant therapy in patients with high-risk melanoma: a systematic review and meta-analysis

BACKGROUND

Based on previous meta-analyses of randomized controlled trials (RCTs), the use of interferon alpha (IFN-alpha) in the adjuvant setting improves disease-free survival (DFS) in patients with high-risk cutaneous melanoma. However, RCTs have yielded conflicting data on the effect of IFN-alpha on overall survival (OS).

METHODS

We conducted a systematic review and meta-analysis to examine the effect of IFN-alpha on DFS and OS in patients with high-risk cutaneous melanoma. The systematic review was performed by searching MEDLINE, EMBASE, Cancerlit, Cochrane, ISI Web of Science, and ASCO databases. The meta-analysis was performed using time-to-event data from which hazard ratios (HRs) and 95% confidence intervals (CIs) of DFS and OS were estimated. Subgroup and meta-regression analyses to investigate the effect of dose and treatment duration were also performed. Statistical tests were two-sided.

RESULTS

The meta-analysis included 14 RCTs, published between 1990 and 2008, and involved 8122 patients, of which 4362 patients were allocated to the IFN-alpha arm. IFN-alpha alone was compared with observation in 12 of the 14 trials, and 17 comparisons (IFN-alpha vs comparator) were generated in total. IFN-alpha treatment was associated with a statistically significant improvement in DFS in 10 of the 17 comparisons (HR for disease recurrence = 0.82, 95% CI = 0.77 to 0.87; P < .001) and improved OS in four of the 14 comparisons (HR for death = 0.89, 95% CI = 0.83 to 0.96; P = .002). No between-study heterogeneity in either DFS or OS was observed. No optimal IFN-alpha dose and/or treatment duration or a subset of patients more responsive to adjuvant therapy was identified using subgroup analysis and meta-regression.

CONCLUSION

In patients with high-risk cutaneous melanoma, IFN-alpha adjuvant treatment showed statistically significant improvement in both DFS and OS.

Sentinel lymph node biopsy in melanoma patients

Appropriate surgical management of regional lymph nodes is critical in patients with cutaneous melanoma. The use of intraoperative lymphatic mapping and sentinel lymph node biopsy (SLNB) has increased significantly in the past decade. SLNB is performed as minimally invasive procedure that provides accurate staging of melanoma patients with no clinically detectable nodal disease. In many melanoma units across the world, it became the standard for detection of occult regional node metastasis in patients with intermediate-thickness primary melanoma. Use of SLNB in patients with thin melanomas is still under evaluation. Although SLNB has been established as staging procedure in melanoma patients, its therapeutic role is still not clear. Large-scale ongoing randomized trials should elucidate whether SLNB with complete lymphadenectomy has a survival benefit in melanoma patients with early lymph node metastases compared to 'watch-and-wait' policy (observation).