Neuron-specific enolase as a prognostic factor in metastatic malignant melanoma

Managing hemolysis in serum neuron-specific enolase measurements - an automated algorithm for routine practice

Neuron-specific enolase (NSE) derived from neurons and peripheral neuroendocrine cells is a biomarker for neuroendocrine tumors and for prognostication in comatose cardiac arrest survivors. However, as platelets and erythrocytes contain NSE, hemolysis causes falsely elevated NSE. We used native serum and hemolysate derived from the same patients to make serial dilutions, and subsequently measured NSE (mNSE) and hemolytic index (HI) in each dilution. An algorithm suitable for the laboratory information system was developed based on the mNSE, HI and the estimated gradient of hemolytic interference from 30 patients. We estimated the associated uncertainty of the corrected NSE (cNSE) results based on the observed range of the gradient and derived an equation for cNSE for samples with limited hemolysis (i.e. 5 < HI ≤ 30): cNSE = mNSE - HI × (0.34 ± 0.23) µg/L. By semi-quantitatively grading the contribution from limited hemolysis, a texted result noting the hemolysis-associated degree of uncertainty can accompany the cNSE result. The major challenge of hemolysis when using serum NSE as a biomarker can be managed using an automated algorithm for correction of NSE results based on degree of hemolysis. However, laboratorians and clinicians should be aware of the limitations associated with in vivo hemolysis.

Usefulness of neuron-specific enolase as a serum marker of metastatic melanoma

Treatment strategies for advanced melanoma are dramatically changing, due to immune-checkpoint inhibitors and BRAF/MEK inhibitors. Nevertheless, reliable serum markers for evaluation of treatment responses and the outcome are still limited. Some previous reports suggested that serum neuron-specific enolase (sNSE) may be a useful marker for melanoma; however, its usefulness is controversial. Moreover, NSE has not been examined in vitro by using melanoma cell lines. We retrospectively evaluated sNSE and serum lactate dehydrogenase (sLDH) levels at the initial diagnosis and during therapy in 33 melanoma patients of various stages. We analyzed the NSE concentrations in cell lysates and supernatants from melanoma cell lines by enzyme-linked immunosorbent assay. The median sNSE was significantly higher in stage IV patients compared with stages I/II and III (16.3, 12.7 and 12.1 ng/mL, respectively). sNSE was elevated in 20% (2/10) of stage III and 61.1% (11/18) of stage IV patients but not in stages I/II. sNSE and sLDH tended to correspond to the total tumor volume (P = 0.48 and 0.58; 95% confidence intervals, 0.005-0172 and 0.776-0.836, respectively). The coincidence rate of sNSE and sLDH in stage IV at the initial diagnosis was 11 of 18 (61.1%). Of the remaining patients, elevated sNSE but not sLDH was observed in five patients (27.8%) and elevated sLDH but not sNSE was observed in two (11.1%). Four of the five patients showing elevated sNSE and normal sLDH were of the mucosal type. NSE was detected in both supernatant and cell lysate of all four melanoma cell lines (0.30-237.32 ng/mL and 137-483.04 ng/mg, respectively). Two cell lines with a high supernatant NSE level contained many dead cells in the supernatant. The combination of sNSE and sLDH could contribute to the early detection of distant metastasis and disease condition evaluations for advanced melanoma patients.

Neuron-Specific Enolase

The clinical value of neuron-specific enolase as a marker in small cell lung cancer, neuroblastoma, melanoma and seminoma has been reviewed The role of serum and cerebrospinal NSE in benign and malignant disease of the central nervous sytem is discussed.

Neuron-Specific Enolase as a Biomarker: Biochemical and Clinical Aspects

Neuron-specific enolase (NSE) is known to be a cell specific isoenzyme of the glycolytic enzyme enolase. In vertebrate organisms three isozymes of enolase, expressed by different genes, are present: enolase α is ubiquitous; enolase β is muscle-specific and enolase γ is neuron-specific. The expression of NSE, which occurs as γγ- and αγ-dimer, is a late event in neural differentiation, thus making it a useful index of neural maturation.NSE is a highly specific marker for neurons and peripheral neuroendocrine cells. As a result of the findings of NSE in specific tissues under normal conditions, increased body fluids levels of NSE may occur with malignant proliferation and thus can be of value in diagnosis, staging and treatment of related neuroendocrine tumours (NETs).NSE is currently the most reliable tumour marker in diagnosis, prognosis and follow-up of small cell lung cancer (SCLC), even though increased levels of NSE have been reported also in non-small cell lung cancer (NSCLC). The level of NSE correlates with tumour burden, number of metastatic sites and response to treatment.NSE can be also useful at diagnosis of NETs and gastroenteropancreatic (GEP)-NETs.Raised serum levels of NSE have been found in all stages of neuroblastoma, although the incidence of increased concentration is greater in widespread and metastatic disease. Moreover, NSE determination in cord blood offers an early postnatal possibility of confirming the diagnosis of neuroblastoma in newborns.NSE has been demonstrated to provide quantitative measures of brain damage and/or to improve the diagnosis and the outcome evaluation in ischaemic stroke, intracerebral hemorrhage, seizures, comatose patients after cardiopulmonary resuscitation for cardiac arrest and traumatic brain injury.Increased NSE serum levels have also been found associated with melanoma, seminoma, renal cell carcinoma, Merkel cell tumour, carcinoid tumours, dysgerminomas and immature teratomas, malignant phaechromocytoma, Guillain-Barré syndrome and Creutzfeldt-Jakob disease.

Primary malignant melanoma of the stomach: report of a case

We report a case of primary malignant melanoma (MM) of the stomach. The patient, a 73-year-old man, was referred to our hospital for investigation of an elevated lesion in the stomach, detected by gastroscopy. On admission, physical examinations and laboratory data were unremarkable. Gastroscopy revealed a pigmented, elevated tumor, approximately 2 cm in diameter, in the posterior wall of the stomach. A biopsy was taken, which resulted in a diagnosis of MM, based on the presence of melanin in tumor cells. F-18 fluorodeoxyglucose positron emission tomography showed no accumulation of tracer except for the tumor in the stomach, indicating that it was a primary MM of the stomach. The patient underwent distal gastrectomy, but died of recurrence 1 year later. Very few cases of primary MM of the stomach have been reported. Thus, we report this case, followed by a review of the literature.

RT-PCR tyrosinase expression in the peripheral blood of melanoma patients

Controversial data are reported in the literature concerning the role of peripheral blood tyrosinase messenger RNA reverse transcription PCR analysis in melanoma patient management. Some papers assess the clinical relationship between tyrosinase expression and disease outcome, while others address the high degree of variability in the positive rate percentage and demonstrate the transient shedding of melanoma cells in the bloodstream. An overview of the current knowledge about the applications and limitations of tyrosinase analysis compared with other biologic markers is presented herein. Tyrosinase expression should not be considered as a tumor burden-related marker in the peripheral blood, but rather as a measure of the potential increased risk of metastatic spreading. In this view, reverse transcription PCR gains a clinical significance when sequential determinations are performed during follow-up, whereas the evaluation of a single sample, either positive or negative, does not bring any additional clinical information.

Comparison of prognostic significance of serum 5-S-Cysteinyldopa, LDH and S-100B protein in Stage III-IV malignant melanoma

5-S-cysteinyldopa is a precursor of pheomelanin. S-100B protein is a low molecular weight, acidic, calcium binding, cytoplasmatic protein. LDH was defined as the most important serum parameter in disseminated melanoma. The aim of the present study was to compare the prognostic values of serum 5-S-Cysteinyldopa, S-100B and LDH concentrations in Stage III-IV melanoma patients. Serum samples were taken from 179 Stage III-IV melanoma patients at diagnosis. Serum 5-S-CD concentrations were determined by HPLC, S-100B protein by immunoluminometric assay while LDH by UV kinetic method. The mean/median concentrations of LDH, S-100B protein and 5-S-CD in Stage III patients ranged around the normal level. In Stage IV, the markers ranked as S100B = 5-S-CD > LDH for sensitivity, S-100B > LDH > 5-S-CD for specificity and LDH = S100B = 5-S-CD for positive predictive value, respectively. Furthermore, mean marker concentrations of patients with progressive disease differed significantly from nonprogresssive cases (when staging categories have been disregarded). Survival analysis indicated, that the initially elevated LDH and S-100B level in Stage IV disease predicts comparably short survival. Results of our study suggest that these serum marker values correlate well with Stages and disease progression. In Stage IV melanoma, the markers had appropriate sensitivity, high specificity as well as important positive predictive value. Among the studied serum markers S-100B protein and LDH proved to be similarly reliable in respect to the clinical outcome.

Cysteine and indole derivatives as markers for malignant melanoma

Malignant melanoma is a skin tumour, which carries a very unfavourable prognosis. The early detection of a melanoma and even more its metastasis is of decisive importance for the survival prognosis of the patients. So there is always a desire for simple, economical and meaningful serological markers. From the cysteine- and indole-related derivatives, 5-S-cysteinyldopa (5-SCD) and 6-hydroxy-5-methoxy-indole-2-carboxylic acid (6H5MI2C) are the most important substances for this purpose. For 5-SCD, the sample pretreatment was carried out either by a manual extraction onto alumina, by an automated method onto boronic acid affinity gels or by an automated solid-phase extraction. For 6H5MI2C, liquid-liquid extractions or direct injection techniques were applied. The chromatographic analyses in the early years were mostly performed with GC-MS. Today HPLC is the nearly exclusively used separation technique. For HPLC, standard RP18 separating columns and usual compositions of eluents were applied. As detectors both the ECD and the FD showed a sufficient sensitivity and selectivity. 5-SCD and 6H5MI2C are very sensitive to light and oxidation. These properties must be taken into account in the complete analysis procedure, including the sample collection, otherwise false low values will result especially for plasma samples. For a critical discussion of the analytical methods and still more for the interpretation of the obtained results, the detailed analytical procedures must be considered. 5-SCD in plasma is one of the best markers of malignant melanoma. It shows an excellent specificity and also an adequate sensitivity in the metastatic melanoma stages. For the detection of primary melanomas and for urine instead of plasma samples, the sensitivity of 5-SCD is generally lower. Altogether, the sensitivity of this parameter is not yet sufficient. 6H5MI2C and other indole derivatives have been investigated far less than 5-SCD. 6H5MI2C correlates less clearly with the different stages of the melanoma and is therefore a less suitable marker. To improve the sensitivity of the findings, in future the investigations should be performed as multi-marker analysis with the simultaneous measurements of more than one marker substance in a given patient sample. Not only one measurement should be carried out per patient, it would be more meaningful to observe the patients with laboratory diagnostics in the follow-up.

Quantification of melanoma-associated molecules in plasma/serum of melanoma patients

Tumor markers for metastatic melanoma have, so far, been infrequently used. Although there is good evidence from several studies that protein S-100B serum measurement could serve as a valid marker for micro- and/or macrometastasis, the S-100B-LIAmat test has not been established as part of national and international recommendations for the care of melanoma patients. Future studies should focus on early detection of metastatic disease with S-100B compared to routine clinical, laboratory and technical evaluations. Furthermore, preliminary, interesting results on the predictive value of S-100B for the monitoring of metastatic patients during treatment should be verified in multicenter trials. The same considerations are true for melanoma-inhibitory activity (MIA), a new and interesting tool for the detection of metastatic melanoma. However, available data on the clinical use of on the MIA-ELISA are too limited to speculate on an even higher sensitivity and specificity than reported for S-100B. Melanin metabolites are candidates for valid melanoma markers, too. Quantification of 5-S-cysteinyldopa from blood or urine of melanoma patients has not been transferred from the laboratory to daily routine due to several technical problems in the assessment of this particular molecule. Cytokines, adhesion molecules and metalloproteinases are shed from melanoma cells into the serum, but these cells are not the only source of elevated serum levels. Several inflammatory conditions are responsible for high serum concentrations of these molecules. In general, they are not sensitive and specific enough to serve as "melanoma markers."

Serum S-100b protein as a prognostic marker in malignant cutaneous melanoma

PURPOSE

To evaluate whether S-100B protein in serum is an independent prognostic marker in malignant melanoma.

MATERIALS AND METHODS

S-100B protein in serum was analyzed in 1,007 consecutive patients with histologically verified cutaneous malignant melanoma. At the time of blood sampling, 876 patients were in clinical stage I, 35 were in stage II, and 96 were in stage III. The serum concentrations of S-100B protein were measured by a luminescence immunoassay (LIA).

RESULTS

The mean serum concentration of S-100B protein was significantly related to clinical stage, with the lowest level in stage I and the highest in stage III. In a multivariate analysis, S-100B protein levels in serum showed the strongest prognostic impact of the factors analyzed with respect to disease-specific survival in clinical stages II to III, followed by clinical stage. Serum S-100B protein was not a significant independent prognostic factor in clinical stage I, where tumor thickness showed the strongest relation to melanoma-specific survival, followed by ulceration and satellites.

CONCLUSION

This investigation contains the largest material of patients so far analyzed with the new LIA assay of S-100B protein in serum and confirms that S-100B protein in serum is correlated with clinical stage and is an independent prognostic marker in clinical stages II and III.

Significance of serum protein S100 levels in screening for melanoma metastasis: does protein S100 enable early detection of melanoma recurrence?

A number of recent reports suggest serum protein S100 as a prognostic parameter in patients with metastatic melanoma. In the present study, serum protein S100 was investigated as a tumour marker for screening for melanoma metastasis in patients attending regular follow-up examinations. During the period from September 1997 to December 1998, serum protein S100 levels were measured by an immunoluminometric assay in 411 consecutive high risk melanoma patients (666 samples) and in 120 control subjects. Melanoma patients with resected primary tumours with a tumour thickness of 1.5 mm or more with resected metastasis were included in the study. Overall, 41 of the 411 patients developed metastasis during the period of observation. According to the distribution of protein S100 levels, the following different cut-off values were examined: 0.08 microg/l (95 percentile of the control group) and 0.13 microg/l (95 percentile of the group of melanoma patients without metastasis). The test efficiency for protein S100 as a diagnostic test for the detection of metastasis was highest for the cut-off value of 0.13 microg/l. In eight of the 41 patients (19.5%), elevation of protein S100 was the first sign of recurrence. Of the 41 patients with metastatic disease, 13 had elevated protein S100, giving a sensitivity of 0.32. The specificity for the detection of metastasis was 0.96. In eight of the 14 patients (57%) who developed distant metastasis, elevated S100 values were the first sign of tumour progression. In conclusion, determination of serum protein S100 levels enables earlier detection of distant metastasis in patients at high risk for metastasis. The impact on survival time needs to be investigated in follow-up studies.

Cathepsin D expression in early cutaneous malignant melanoma

BACKGROUND

The aspartic proteinase cathepsin D is believed to be associated with proteolytic processes leading to the invasion and seeding of tumor cells. An association between cathepsin D tissue concentration and aggressiveness of tumors has been detected in different cancer types, as well as in metastatic melanoma.

METHODS

The concentration of cathepsin D was measured immunoradiometrically (ELSA-CATH-D kit, CIS Bio International) in the cytosols of 51 primary cutaneous melanomas (with Breslow index < 4 mm) to estimate the tissue concentrations of cathepsin D in early cutaneous melanoma.

RESULTS

A significantly elevated concentration of cathepsin D was measured in the tumor cytosols as compared to adjacent normal tissue (44.2 vs. 14.7 pmol/mg of total protein, P < 0.001).

CONCLUSIONS

Our results indicate that cathepsin D is expressed at high levels by melanoma cells. The extremely high expression of cathepsin D in two of our patients, with later progression of the disease over a 42-month follow-up period, suggests a possible correlation between the cathepsin D tissue concentration and the prognosis of primary cutaneous malignant melanoma.

Serological markers for melanoma

We present a review of current literature concerning the significance of serological markers in melanoma patients. Results for cytokines, cytokine receptors, cell adhesion molecules, S100 protein, melanoma inhibitory activity, tissue-specific reverse transcription-polymerase chain reaction, neurone-specific enolase, lipid-bound sialic acid and melanin metabolites such as 5-S-cysteinyldopa and 6-hydroxy-5-methoxyindole-2-carboxylic acid are discussed. For most of these substances, serum levels are more pronounced in the more advanced stages of disease. Therefore, these markers seem to have no place in the early detection of melanoma. On the other hand, sensitivity in the advanced stages of disease seems to be < 100%, compromising their use as a new staging procedure. Some markers show promising results as a possible prognostic factor in the early detection of disease progression or in the prediction of therapy outcome. If confirmed by further studies, this could direct future therapeutic strategies and could help to select patients who would benefit most from more aggressive (adjuvant) therapies. In addition, the study of some of these substances could add to the knowledge of tumour biology and immunology.

S-100 and NSE as serum markers in melanoma

S-100 protein and neuron-specific enolase (NSE) have recently been proposed as serum markers for melanoma. In this study NSE and S-100 serum levels were assayed by commercial IRMA methods in 53 patients with melanoma. The overall prevalence of abnormal marker levels was similar for NSE (26%) and S-100 (30%). The 24 patients in stages I and II had uniformly normal S-100 levels, but abnormal NSE levels were observed in 3 out of the 12 patients in stage II (33%) and in 1 out of 12 in stage I. NSE appears thus to be the marker of choice in the early stages, where its increase points to disease progression. In patients in stages III and IV the prevalence of abnormal values was 34% for NSE and 55% for S-100 (p = < 0.05). In the latter group diagnostic sensitivity increased to 62% if isolated elevation of each marker was considered. In patients with advanced stage disease, both NSE and S-100 should be assayed.

Clinical significance of serum S100 in metastatic malignant melanoma

The clinical significance of serum S100 was assessed in comparison to neuron-specific enolase (NSE) in 126 patients with malignant melanoma: 80 patients with clinical stage I/II, 23 patients with stage III and 23 patients with stage IV according to the criteria of the American Joint Committee on Cancer (AJCC). Using cut-off values of 0.15 microgram/l for S100 and 12.5 micrograms/l for NSE, the sensitivity was found to be 1.3% (1/80) for S100 and 8.75% (7/80) for NSE in patients with stage I/II, 8.7% (2/23) for S100 and 13% (8/23) for NSE in patients with stage III, and 73.9% (17/23) for S100 and 34.8% (8/23) for NSE in patients with stage IV disease (P < 0.05). In 6 patients with stage III/IV tumours, serial measurement of serum S100 and NSE was performed. A rise of serum S100 indicated progression of the disease; a decline indicated response to treatment. Our preliminary results support the value of serum S100 as an adjunct to the clinical staging and monitoring of metastatic malignant melanoma.

Clinical significance of serum S100 in metastatic malignant melanoma

The clinical significance of serum S100 was assessed in comparison to neuron-specific enolase (NSE) in 126 patients with malignant melanoma: 80 patients with clinical stage I/II, 23 patients with stage III and 23 patients with stage IV according to the criteria of the American Joint Committee on Cancer (AJCC). Using cut-off values of 0.15 micrograms/l for S100 and 12.5 micrograms/l for NSE, the sensitivity was found to be 1.3% (1/80) for S100 and 8.75% (7/80) for NSE in patients with stage I/II, 8.7% (2/23) for S100 and 13% (8/23) for NSE in patients with stage III, and 73.9% (17/23) for S100 and 34.8% (8/23) for NSE in patients with stage IV disease (P < 0.05). In 6 patients with stage III/IV tumours, serial measurement of serum S100 and NSE was performed. A rise of serum S100 indicated progression of the disease; a decline indicated response to treatment. Our preliminary results support the value of serum S100 as an adjunct to the clinical staging and monitoring of metastatic malignant melanoma.