Serum Protein S-100 Predicts Clinical Outcome in Patients with Melanoma Treated with Adjuvant Interferon – Comparison with Tyrosinase RT-PCR

Phase I, open-label study of pasireotide in patients with BRAF-wild type and NRAS-wild type, unresectable and/or metastatic melanoma

Introduction

Somatostatin analogues exert antitumour activity via direct and indirect mechanisms. The present study was designed to assess the safety and efficacy of pasireotide in patients with BRAF-wild type (WT) and NRAS-WT metastatic melanoma.

Patients and methods

Patients with unresectable and/or metastatic melanoma or Merkel cell carcinoma were eligible. Pasireotide was administered at different doses for ≤8 weeks in dose-escalation phase, followed by long-acting pasireotide 80 mg or lower dose in case of toxicity in follow-up phase up to six additional months. Primary endpoint was safety in the first 8 weeks of dose-escalation phase.

Results

The study was terminated early due to slow recruitment. Of the 10 patients with metastatic melanoma enrolled, only four reached the high dose level: two patients reached 3600 µg in dose-escalation and follow-up phases and two patients reached 3600 µg in dose-escalation and long-acting pasireotide 80 mg in follow-up phases and were stable for >5 months. Most common adverse events (AEs) during dose-escalation phase in ≥2 patients (20%) were: diarrhoea (50%), nausea (50%), fatigue (20%), hyperglycaemia (20%), hypophosphatemia (20%), chills (20%) and tumour pain (20%). Grade 3 or 4 study drug-related AEs were diarrhoea and nausea, reported in one patient. Partial response was documented in one patient and stable disease in another.

Conclusions

Pasireotide was well tolerated, and safety results were similar to those previously reported in other indications. Further studies are needed to evaluate its antitumour activity alone and in combination with other drugs in melanoma.

Prognostic significance of serum S100B protein in high-risk surgically resected melanoma patients participating in Intergroup Trial ECOG 1694

PURPOSE

We evaluated adjuvant trial E1694 to more precisely define the prognostic significance of serum S100B in patients with high-risk resected melanoma.

PATIENTS AND METHODS

Sera from 670 E1694 patients banked at baseline and three additional time points were tested for S100B protein using chemiluminescence.

RESULTS

S100B testing results showed that the higher the S100B level is, the higher the risk of relapse and death, regardless of the cutoff value. Univariate analysis showed that baseline S100B > or = 0.15 microg/L is significantly correlated with overall survival (OS; P = .01). Multivariate analysis was performed adjusting for significant prognostic factors (ulceration and lymph node status) and treatment. Baseline S100B was a significant prognostic factor for survival (hazard ratio = 1.39; 95% CI, 1.01 to 1.92; P = .043). S100B values measured at later time points over 1 year were also demonstrated to be significant prognostic factors for relapse-free survival (RFS) and OS. Lower S100B values at baseline and during follow-up were associated with longer survival. A changing S100B from low at baseline to high on follow-up seemed to be associated with the worst RFS and OS.

CONCLUSION

For patients with high-risk surgically resected melanoma, a high baseline or increasing serum S100B is an independent prognostic marker of risk for mortality that may allow us to refine the application of adjuvant therapy in the future.

Circulating tumor cells: detection, molecular profiling and future prospects

Disseminated malignancy is responsible for the vast majority of cancer-related deaths. During this process, circulating tumor cells (CTC) are generated, spread from the primary tumor, colonize distant organs and lead to overt metastatic disease. CTC are essential for establishing metastasis; however, they are not sufficient as this process is highly inefficient and most will fail to grow in target sites. Several CTC die during migration while others remain dormant for several years and very few grow into macrometastases. CTC have been well documented in the bloodstream of cancer patients; however, the clinical relevance of this detection is still the subject of controversies and their biology is poorly understood. Indeed, available markers fail to distinguish between subgroups of CTC, and several current methods lack sensitivity, specificity or reproducibility in CTC characterization and detection. The advent of more precise technologies is renewing the interest in CTC biology. We will review herein recent findings on CTC biology, on the role of host-tumor interactions in CTC shedding and implantation, available methods of CTC detection and future perspectives for the molecular characterization of the CTC subset(s) responsible for the development of metastasis. Ultimately, understanding CTC biology and host-tumor 'complementarities' will help define metastasis-related biomarkers providing formidable and tailored novel therapeutic targets.

Tumour assessment in advanced melanoma: value of FDG-PET/CT in patients with elevated serum S-100B

PURPOSE

To evaluate the usefulness of PET/CT in melanoma patients with an elevated serum S-100B tumour marker level.

METHODS

Out of 165 consecutive high-risk melanoma patients referred for PET/CT imaging, 47 had elevated (>0.2 microg/l) S-100B serum levels and a contemporaneous 18F-FDG PET/CT scan. PET/CT scans were evaluated for the presence of metastases. To produce a composite reference standard, we used cytological, histological, MRI and PET/CT follow-up findings as well as clinical and S-100B follow-up.

RESULTS

Among the 47 patients with increased S-100B levels, PET/CT correctly identified metastases in 38 (30 distant metastases and eight lymph node metastases). In one patient with cervical lymph node metastases, PET/CT was negative. Eight patients had no metastases and PET/CT correctly excluded metastases in all of them. Overall sensitivity for metastases was 97% (38/39), specificity 100% (8/8) and accuracy 98% (46/47). S-100B was significantly higher in patients with distant metastases (mean 1.93 microg/l, range 0.3-14.3 microg/l) than in patients with lymph node metastases (mean 0.49 microg/l, range 0.3-1.6 microg/l, p=0.003) or patients without metastases (mean 0.625 microg/l, range 0.3-2.6 microg/l, p=0.007). However, 6 of 14 patients with a tumour marker level of 0.3 microg/l had no metastases.

CONCLUSION

In melanoma patients with elevated S-100B tumour marker levels, FDG-PET/CT accurately identifies lymph node or distant metastases and reliably excludes metastases. Because of the significant number of false positive S-100B tumour marker determinations (17%), we recommend repetition of tumour marker measurements if elevated S-100B levels occur before extensive imaging is used.

The prognostic value of circulating tumor cells in patients with melanoma: a systematic review and meta-analysis

BACKGROUND

The detection of circulating tumor cells (CTC) in patients with melanoma represents an appealing prognostic tool, but no consensus exists on this topic. We aimed to comprehensively and quantitatively summarize the evidence for the use of CTC to predict patients' clinical outcome.

METHODS

Fifty-three studies enrolling 5,433 patients were reviewed. Correlation of CTC status with tumor-node-metastasis disease stage and patients' overall (OS) and progression-free (PFS) survival was assessed by means of association statistics and meta-analysis, respectively.

RESULTS

CTC status correlated with both tumor-node-metastasis stage (stage I, 32%; stage II, 41.7%; stage III, 41.1%; stage IV, 47.4%; P(trend) < 0.0001) and survival (OS: hazard ratio, 2.42; 95% confidence interval, 1.7-3.45, P < 0.0001; PFS: hazard ratio, 2.45; 95% confidence interval, 1.78-3.38; P < 0.0001). However, statistical heterogeneity was significant for both OS and PFS, likely underscoring the wide variability in study design. Furthermore, CTC positivity rates in early stages were higher and in the metastatic setting were lower than expected, which indicates an unsatisfactory accuracy of currently available CTC detection assays.

CONCLUSIONS

Our findings suggest that CTC might have a clinically valuable prognostic power in patients with melanoma. However, the heterogeneity of the studies thus far published warrants caution not to overestimate the favorable results of pooled data.

Circulating tumor cells: the 'leukemic phase' of solid cancers

It is well known that malignant cells circulate in the bloodstream of patients with solid tumors. However, the biological significance of circulating tumor cells (CTCs) and the clinical relevance of their detection are still debated. Besides technical issues regarding CTC-detection methods, discontinuous shedding of CTCs from established cancer deposits, genomic instability and metastatic inefficiency might underlie the conflicting results currently available. Nevertheless, technological advances and recent clinical findings are prompting researchers to dissect CTC biology further. Here, we review these recent findings, and discuss the prospects for the identification and molecular characterization of the CTC subset that is responsible for metastasis development. This would provide a formidable tool for prognosis evaluation, anticancer-drug development and, ultimately, cancer-therapy personalization.