[Epiluminescence microscopy in diagnosis of pigmented skin tumors].
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Diagnosis, Differential↗
Biomedical subjects
H Pehamberger
Publications and source records attributed to H Pehamberger.
N-ras oncogene expression changes the growth characteristics of human melanoma in two independent SCID-hu mouse models.
Fifteen percent of all human melanomas carry mutations in ras genes, the majority of which are located in codon 61 of the N-ras gene. However, the biological significance of these mutations is as yet unknown. In this study, we investigated the influence of N-ras oncogene products mutated in codon 61 on the growth characteristics of human melanoma in vivo by establishing 2 SCID-hu mouse xenotransplantation models. Tumors grown in SCID mice injected with human melanoma carrying activated N-ras genes were significantly larger (p < 0.004) than tumors grown in animals injected with the appropriate control transfectants. Additionally, tumors with N-ras point mutations clearly showed a more pleomorphic phenotype than the control groups. Our results, obtained in 2 independent SCID-hu xenotransplantation models, suggest that mutated N-ras oncogene expression may be an important factor influencing growth characteristics of human melanoma without altering metastatic potential. These novel in vivo model systems provide a tool for further study of the biology of mutated ras in melanoma and should also prove useful for testing new and improved treatment strategies for human melanoma carrying mutated ras genes.
Animals↗
Azelaic acid decreases the fibrinolytic potential of cultured human melanoma cells in vitro.
Azelaic acid (AZA) has been used successfully in the treatment of lentigo maligna melanoma. Since it is generally accepted that the fibrinolytic potential of tumour cells is related to their malignant phenotype, it was the aim of this study to investigate the effect of AZA on the fibrinolytic potential of three different human melanoma cell lines (Bowes, GUBSB and MJZJ). Melanoma cells were incubated with AZA in doses ranging from 10(-2) M to 4 x 10(-2) M for 5, 8 and 24 h. The expression of tissue-type plasminogen activator (t-PA), urokinase-type PA (u-PA) and PA inhibitor-1 (PAI-1) in such treated cells was investigated by specific ELISAs on the protein level and by Northern blotting on the mRNA level. AZA caused a time and dose dependent decrease in the fibrinolytic potential of all three cell lines investigated by decreasing t-PA antigen in Bowes, by decreasing u-PA antigen in GUBSB and by increasing PAI-1 antigen in MJZJ cells, respectively. There was no significant difference between the viability of cells in control cultures and those treated with AZA. The effect of AZA on specific mRNA for t-PA in Bowes cells, u-PA in GUBSB and PAI-1 in MJZJ was consistent with its effect on the secretion of these fibrinolytic proteins by the respective cells. The results show that AZA decreases the fibrinolytic potential of the three human melanoma cell lines in vitro. This decrease may be operative in the mechanism by which AZA has been shown to affect malignant melanoma in vivo.
Antineoplastic Agents↗
Measurement of extracellular fluid carboplatin kinetics in melanoma metastases with microdialysis.
Clinical anti-tumour efficacy of anti-cancer drugs is a function of dose intensity, i.e. the concentration--time profile in tumour tissue. Hence, information on drug concentration profiles in tumours is of critical importance but appropriate methods for measurement are lacking. The aim of the present study was to obtain, by microdialysis sampling, concentration--time profiles in a solid tumour (melanoma) of a model anti-cancer drug, carboplatin, and thereby to assess the scope of microdialysis for tumour pharmacokinetic studies in man. Six patients with cutaneous melanoma metastases at the extremities or body trunk, scheduled to receive carboplatin (400 mg m-2 i.v.) were studied. Carboplatin concentrations were monitored in serum, intratumoral and subcutaneous tissue. Calibration of the microdialysis probes was carried out in vitro and in vivo with use of the retrodialysis method. Complete carboplatin concentration vs time profiles in tumour and subcutaneous tissue were obtained. Major pharmacokinetic parameters (maximum concentration, time to maximum concentration, area under the curve, elimination half-life) were calculated for tissues and tumour/serum concentration ratios for carboplatin were derived. Mean free concentrations of carboplatin in cutaneous melanoma metastases reached only about 50-60% of total serum levels; maximal intratumoral concentrations were 7.6 (+/-2.0; s.e.m.) microgram/ml, mean concentrations in subcutaneous tissue were similar to those in tumour. The present study demonstrates that microdialysis is a novel tool for measuring drug concentrations in solid tumours in humans in vivo and appears to be a valuable addition for pharmacokinetic/pharmacodynamic studies in oncology.
Antineoplastic Agents↗
Limitations of high frequency ultrasound in determining the invasiveness of cutaneous malignant melanoma.
Preoperative assessment of melanoma invasion by sonometry has been reported to exhibit a high correlation with postoperative histometry based on the determination of a regression coefficient. We believe that this approach is not adequate and that it can be misleading. We therefore applied an appropriate statistical approach to our data to re-examine this issue. Preoperative measurements by sonometry were compared with postoperative histometry in 71 consecutive patients with the clinical diagnosis of malignant melanoma. Patients with the histological diagnosis of melanoma in situ (n = 13) were excluded from this comparison, as sonometry cannot distinguish structures restricted to the epidermis and Breslow thickness is not routinely determined in Clark level I melanomas. The agreement between sonometry and histometry was analysed by plotting the mean of the two methods against their difference. By linear regression analysis the correlation coefficient (r) in the invasive melanomas (n = 58) was found to be 0.92. The median thickness of the invasive tumours by sonometry was 1.36 mm, and by histometry 0.89 mm. In 95% of the cases sonometry differed by 37% above to 48% below the values obtained by histometry. Thus, we conclude that the accuracy of sonometry in predicting preoperative tumour thickness- and tumour invasiveness-is far lower than previously reported.
Adult↗
Increased nuclear volume in metastasizing "thick" melanomas.
Tumor invasion is the most reliable prognostic factor for primary stage I melanoma. "Thick" melanomas, with a Breslow thickness of more than 4 mm, tend to have a poor prognosis. Exceptions occur: some patients have no further recurrence of tumor. In an attempt to determine prognostic markers for "thick" clinical stage I melanomas, we investigated the volume-weighted mean nuclear volume of primary melanomas with tumor invasions > or = 4.0 mm in 32 patients. Seventeen of these patients developed melanoma metastases within a follow-up period of 60 mo; 15 patients who did not developed metastases and were comparable with regard to clinical and histological criteria were selected as a comparison group. Volume-weighted mean nuclear volume (Vv) is determined by a technique that permits an unbiased, efficient, shape- and orientation-independent, 3-dimensional estimation of nuclear size in tissues. This technique has been employed successfully in the prognostic assessment of stage I and II melanomas and was recently proven to be a sensitive marker for thin, high-risk melanomas. In our patients, Vv was determined by computer-assisted image analysis on Feulgen-stained sections by stereologic estimation of the Vv. The mean Vv (+/-SD) of primary melanomas with subsequent metastatic course was 794.99 +/- 209.18 micron3 (range: 409.48-1161.9 micron3), whereas primary melanoma lesions without subsequent metastases exhibited a mean Vv 640.54 +/- 205.07 micron3 (range: 206.7-927.48 micron3). This difference was found to be statistically significant (p = 0.0439). "Thick" melanomas with subsequent metastases thus exhibited a significantly higher Vv than did melanomas that did not metastasize.
Adult↗
Characterization of peripheral-compartment kinetics of antibiotics by in vivo microdialysis in humans.
The calculation of pharmacokinetic/pharmacodynamic surrogates from concentrations in serum has been shown to yield important information for the evaluation of antibiotic regimens. Calculations based on concentrations in serum, however, may not necessarily be appropriate for peripheral-compartment infections. The aim of the present study was to apply the microdialysis technique for the study of the peripheral-compartment pharmacokinetics of select antibiotics in humans. Microdialysis probes were inserted into the skeletal muscle and adipose tissue of healthy volunteers and into inflamed and noninflamed dermis of patients with cellulitis. Thereafter, volunteers received either cefodizime (2,000 mg as an intravenous bolus; n = 6), cefpirome (2,000 mg as an intravenous bolus; n = 6), fleroxacin (400 mg orally n = 6), or dirithromycin (250 mg orally; n = 4); the patients received phenoxymethylpenicillin (4.5 x 10(6) U orally; n = 3). Complete concentration-versus-time profiles for serum and tissues could be obtained for all compounds. Major pharmacokinetic parameters (elimination half-life, peak concentration in serum, time to peak concentration, area under the concentration-time curve [AUC], and AUC/MIC ratio) were calculated for tissues. For cefodizime and cefpirome, the AUCtissue/AUCserum ratios were 0.12 to 0.35 and 1.20 to 1.79, respectively. The AUCtissue/AUCserum ratios were 0.34 to 0.38 for fleroxacin and 0.42 to 0.49 for dirithromycin. There was no visible difference in the time course of phenoxymethylpenicillin in inflamed and noninflamed dermis. We demonstrated, by means of microdialysis, that the concept of pharmacokinetic/pharmacodynamic surrogate markers for evaluation of antibiotic regimens originally developed for serum pharmacokinetics can be extended to peripheral-tissue pharmacokinetics. This novel information may be useful for the rational development of dosage schedules and may improve predictions regarding therapeutic outcome.
Adipose Tissue↗
Epiluminescence microscopy. A useful tool for the diagnosis of pigmented skin lesions for formally trained dermatologists.
BACKGROUND AND DESIGN: Epiluminescence microscopy (ELM) is a noninvasive technique that, by employing the optical phenomenon of oil immersion, makes subsurface structures of the skin accessible for in vivo examination and thus provides additional criteria for the clinical diagnosis of pigmented skin lesions. At present, almost all studies about the value and clinical importance of ELM are based on data derived from ELM experts (ie, dermatologists specifically trained in this technique). In the present study, we attempt to determine whether the clinical diagnosis of pigmented skin lesions is significantly improved using ELM and whether ELM-trained individuals and dermatologists not trained in this technique profit equally from this technique. Randomly selected histologically proven pigmented skin lesion specimens, photographed with (ELM) and without oil immersion (surface microscopy) were presented by slide projection to six ELM experts and 13 ELM nonexperts (ie, dermatologists not formally trained in ELM) for diagnosis. To evaluate the diagnostic performance of ELM experts and nonexperts with and without the oil immersion technique (ie, ELM vs surface microscopy), the following parameters were obtained: intraobserver and interobserver agreement by kappa statistics and sensitivity and specificity of diagnostic performance. RESULTS: Our results show that by using the ELM technique the ELM experts reach a substantially better intraobserver agreement than nonexperts (median kappa, 0.56 vs 0.36). The interobserver agreement was markedly increased in the ELM experts group (average gain, 7%) but decreased in the ELM nonexperts group (average loss, 6%). The sensitivity of diagnosis was significantly increased in the ELM experts group (average gain, 10%), but decreased in the nonexperts group (average loss, 10%). Finally, the specificity of diagnosis was excellent in the ELM experts group, both with and without oil immersion (0.91) and was somewhat improved by ELM in the nonexperts group (0.77 vs 0.85). CONCLUSIONS: We conclude that the ELM technique increases sensitivity in formally trained dermatologists, but may decrease the diagnostic ability in dermatologists not formally trained in the ELM technique. Consequently, formal broad-based training in ELM should be offered to the dermatologic community.
Clinical Competence↗
Effects of cisplatin on urinary thromboxane B2 excretion.
PURPOSE: Thromboxane A2 (TxA2) is implicated in the pathogenesis of various forms of drug-induced renal damage. Based on previous functional studies, we postulated that cis-dichlorodiammineplatinum (cisplatin) induces intrarenal TxA2 synthesis. To test this hypothesis, we measured urinary excretion of thromboxane B2 (TxB2), the stable inactive metabolite of TxA2, during and after cisplatin administration. PATIENTS AND METHODS: The study included 16 patients with malignant disease who were scheduled to receive cisplatin (100 mg/m2) and 11 healthy subjects who received the same amount of fluid loading and the same concomitant medication as the patients but no cisplatin. Total urine output was collected in seven intervals from 24 hours before until 72 hours after the start of prehydration. Urinary immunoreactive TxB2 was measured. RESULTS: There was a marked increase (4.5 +/- 1.6-fold; mean +/- SEM) in urinary TxB2 excretion in patients during and immediately after cisplatin infusion. This increase was significant compared with baseline and the control group. CONCLUSION: High-dose cisplatin causes an acute increase in urinary excretion of TxB2. This likely represents enhanced intrarenal synthesis of TxA2, in response to an acute damaging effect of cisplatin on the kidneys. These findings warrant further studies to evaluate the renoprotective effect of anti-TxA2 intervention in patients receiving high-dose cisplatin.
Acetylglucosaminidase↗
Phosphorothioate oligonucleotides reduce melanoma growth in a SCID-hu mouse model by a nonantisense mechanism.
In our efforts to investigate the biologic role of Ha-ras oncogenes in human melanoma by Ha-ras phosphorothioate antisense oligonucleotides, we observed that antisense, sense, and scrambled control oligonucleotides at a concentration of 10 microM all similarly and strongly inhibited growth of our human melanoma target cell line SK-2 in vitro but without specific decrease of the target protein. Cell numbers with respect to the untreated control were reduced by 84% +/- 4.2% (ISD), 82.9% +/- 3.6%, and 84% +/- 3%, respectively. In vivo studies in a SCID-hu mouse model confirmed these findings. Both antisense and sense control oligonucleotides administered through osmotic pumps significantly (p < 0.006) reduced the mean tumor weight (1.5 g +/- 0.4 g and 1.8 g +/- 0.8 g, respectively) in comparison with saline-treated (5.7 g +/- 0.7 g) or untreated control animals (5.8 g +/- 1.0 g). The vascularity of oligonucleotide-treated tumors was greatly reduced. Clinical signs of oligonucleotide-related toxicity were not observed, and there was no evidence of histopathologic alterations in a variety of mouse tissues. We could demonstrate that the antimelanoma effects can be abrogated in vitro by adding basic fibroblast growth factor (bFGF). In the context of the importance of bFGF in melanocyte biology and angiogenesis, we argue in favor of an interaction between polyanionic phosphorothioate oligonucleotides and bFGF in our melanoma system. These findings stress the notion that phosphorothioate oligonucleotides may be promising antineoplastic lead compounds capable of employing antitumor effects by mechanisms other than specific inhibition of gene expression.
Animals↗
T-cell receptor repertoire of lymphocytes infiltrating cutaneous melanoma is predominated by V alpha specificities present in T-cells of normal human skin.
Lymphocytes infiltrating solid tumors can be propagated in vitro with interleukin 2 and are then capable, as CD8+ cytotoxic T-cells, of specific lysis of autologous tumor targets in a class I-restricted manner. Since the specificity of these cells is determined by their T-cell receptor (TCR) configuration, the aim of this study was to delineate the TCR V alpha repertoire of tumor-infiltrating lymphocytes within 24 melanoma specimens and to compare these data with the TCR expression pattern of unaffected peritumoral and normal human skin. While lymphocytes within all skin specimens tested expressed a substantial, albeit limited, heterogeneity of V alpha specificities with an average number of 9.0 different V alpha gene segments, the V alpha repertoire within cutaneous melanoma lesions was significantly more restricted (mean of V alpha expression, 3.86; P < 0.001) with a predominance of only 3 V alpha families (V alpha 13, V alpha 15, and V alpha 16), all of which were also found to be expressed within normal skin. Collectively, the fact that the TCR V alpha repertoire in melanoma is skewed toward the predominance of only a few V alpha regions may be indicative of a limited number of melanoma-associated antigenic determinants being involved in the anti-tumor immune response.
Adult↗
Immunohistological analysis of anti-melanoma host responses.
Various clinical and experimental observations point to the existence of an immunological host defense in cutaneous malignant melanoma. To identify the major effector mechanisms mediating the specific anti-tumor immune response, we examined 23 benign and neoplastic melanocytic lesions (3 nevi, 14 primary melanomas, and 3 cutaneous and 3 systemic metastases) by quantitative immunohistology, and correlated these results with the histopathological and clinical subtypes of malignant melanoma. Our analyses indicate that CD3+ T-cell receptor alpha/beta-expressing lymphocytes are the prevailing leukocyte subset in primary as well as secondary malignant melanoma. We further observed that in early lesions (< 0.75 mm) of superficial spreading melanoma the vast majority of tumor-infiltrating lymphocytes (TIL) belong to the CD4+ subset and frequently express CD45RA antigens. In more advanced tumors, the contribution of CD8+ TIL gradually increases, indicating that the quality of the anti-tumor immune response changes during the course of the disease. Finally, we found that a varying percentage of cutaneous TIL express the cutaneous leukocyte antigen which is defined by the monoclonal antibody HECA 452 and preferentially expressed by skin-seeking memory T cells. In contrast, extracutaneous melanoma metastases (liver, brain, ovary) were completely devoid of HECA 452-reactive lymphocytes. These findings suggest that lymphocytes infiltrating cutaneous melanomas belong to a memory/effector T-cell subset functionally associated with the skin.
Antibodies, Monoclonal↗
Application of an artificial neural network in epiluminescence microscopy pattern analysis of pigmented skin lesions: a pilot study.
In vivo epiluminescence microscopy (ELM) is a non-invasive technique which improves the clinical diagnosis of naevi and malignant melanoma by providing diagnostic criteria that cannot be appreciated by the naked eye. The present study investigated whether ELM criteria pattern analysis can be employed in an objective, observer-trained, computer-aided diagnostic system, and whether artificial neural networks (ANN) can be applied to the diagnosis of pigmented skin lesions (PSL). The ELM criteria patterns of 200 PSL oil immersion images (60 common naevi, 60 dysplastic naevi, and 80 malignant melanomas) were analysed using a standardized questionnaire. One hundred randomly assigned PSL were used as a training set for an ANN, the remaining 100 PSL serving as the test set. The ANN was trained by backward propagation according to the histological diagnosis, and its performance was compared with that of human investigators. Out of the test set the human investigators correctly diagnosed 88% of PSL and the ANN 86%. In a dichotomized model comparing common, compound, and dysplastic naevi vs. malignant melanoma, i.e. benign vs. malignant PSL, the sensitivity and specificity of human diagnosis was 95 and 90%, respectively, whereas the sensitivity and specificity of the ANN diagnosis was 95 and 88%. Our data indicate that artificial neural networks can be trained to diagnose PSL at a human expert level, based on patterns provided by ELM criteria. We suggest that this technique offers a new approach to the diagnosis of PSL.
Diagnosis, Computer-Assisted↗
Epiluminescence microscopy: a new approach to the early detection of melanoma.
ELM is a new approach to the diagnosis of pigmented skin lesions that holds considerable promise. It reveals a new dimension of in vivo morphology that can be used when the diagnostic criteria employed in routine visual diagnosis fail. It does not add to the diagnostic armamentarium available for unequivocal lesions, but has significant value for those equivocal, small, pigmented skin lesions that pose major diagnostic problems even for experienced clinicians. Prerequisites for a sensible approach to ELM include recognition of new morphologic ELM criteria and employment of these criteria in an analytic process called pattern analysis. As in clinical dermatology, ELM depends heavily on a learning process and, of course, on experience. ELM increases diagnostic accuracy for pigmented skin lesions in that it helps to distinguish between melanocytic and non-melanocytic pigmented lesions, and between benign and malignant growth patterns. Thus, ELM has the potential to overcome the diagnostic limitations encountered in clinical dermatology when small, early pigmented lesions are encountered that do not yet express the full complement of diagnostic features needed to arrive at a correct diagnosis. The fact that it is a noninvasive, in vivo method makes it even more attractive as a diagnostic tool in clinical practice. ELM already has proven to be of great practical value in several centers by increasing the probability that early melanoma will not be overlooked and by helping to prevent unnecessary major surgery in patients in whom a non-melanocytic or benign pigmentary lesion is suspected clinically to be a melanoma. It eventually may prove valuable for patients with dysplastic nevi by helping determine which lesions need to be removed. Of course, ELM also has limitations. It does not provide 100% diagnostic accuracy and is of little help in small lesions that are pigmented maximally and uniformly because these do not reveal the criteria necessary for ELM pattern analysis. At this stage, therefore, ELM does not replace histopathologic examination. Undoubtedly, ELM can be improved, and continued studies will reveal just how reliable the individual criteria discussed here eventually will prove to be in clinical practice. This requires continuing to accumulate and analyze data, and instituting teaching programs to familiarize dermatologists with ELM criteria and their use in pattern analysis. It is certain, however, that, just as clinicians have learned to employ the "ABCD" rules in visually recognizing and diagnosing melanoma, they will learn this new and more subtle approach to the previously unknown morphologic features that characterize benign and malignant pigmentary lesions on ELM.(ABSTRACT TRUNCATED AT 400 WORDS)
Diagnosis, Differential↗
Estimation of the volume-weighted mean nuclear volume discriminates Spitz's nevi from nodular malignant melanomas.
BACKGROUND: Spitz's nevi are benign melanocytic skin tumors that are usually differentiated from nodular malignant melanomas by histopathologic criteria. Often, however, the architectural pattern and cytologic features of Spitz's nevi and nodular melanomas are similar. Hence, Spitz's nevi may be confused with nodular malignant melanomas at the histopathologic level. EXPERIMENTAL DESIGN: The determination of volume-weighted mean nuclear volume (Vv) uses a technique that permits an unbiased and efficient estimation of nuclear volumes in tissues. In this study, Vv was determined in 13 Spitz's nevi and 14 nodular malignant melanomas to investigate whether this stereologic approach may be of use in the differentiation of these two tumors. Vv was determined by computer-assisted image analysis (IBAS 20, Kontron, Germany) on Feulgen-stained sections using stereologic estimation of the Vv. RESULTS: The Vv (+/- SD) of Spitz's nevi was 491.6 micron3 (SD +/- 175.1), whereas nodular malignant melanomas exhibit a significantly higher (p < 0.001) Vv of 775.2 micron3 (SD +/- 205.4). This difference was even more pronounced when the deeper portions of the lesions (Spitz's nevi: 443.1 micron3, SD +/- 142.4; nodular malignant melanomas: 864.1, SD +/- 169.6) were investigated. In addition, we found that in relation to the depth of the lesions the mean Vv decreased in Spitz's nevi, whereas it increased in nodular melanomas. CONCLUSIONS: We found that (i) nodular malignant melanomas reveal a larger Vv than Spitz's nevi in general, and (ii) in contrast to malignant melanomas, the Vv of nevomelanocytes in Spitz's nevi decreases in the deeper portions of the dermis. Thus, Vv may be regarded as a helpful tool for the differential diagnosis of Spitz's nevi and nodular malignant melanomas.
Cell Nucleus↗
Tetrasomy 8 in acute monoblastic leukemia (AML-M5a) with myelosarcomatosis of the skin.
We report a new case with isolated tetrasomy 8, an 82-year-old female patient in whom multiple disseminated nodular skin infiltrations up to 5 cm in diameter preceded acute monoblastic leukemia (AML-M5a). Despite an initial response to chemotherapy and radiotherapy, the patient died 1 year after diagnosis of relapsed leukemia. To assess the size of the tetrasomic clone, fluorescence in situ hybridization (FISH) analysis with a centromere-specific chromosome 8 probe was performed. Seventy percent of interphase cells showed four signals and 22% showed three signals. Because this trisomic clone was not detected by conventional cytogenetics, tetrasomic cells may have a proliferation advantage in vitro. Whether tetrasomy 8 arises from a simultaneous mitotic nondisjunction of both chromosomes 8 during one cell division or evolves secondarily from trisomy 8 through a second mitotic error is not known. Alternatively, trisomy 8 may originate from tetrasomy 8 by loss of one chromosome 8.
Aged↗
Nonbullous pemphigoid: prodrome of bullous pemphigoid or a distinct pemphigoid variant?
We describe two patients with pruritic, mainly urticarial or eczematous lesions associated with peripheral blood eosinophilia. No vesicles or blisters developed in either patient throughout the course of the disease (29 and 38 months, respectively). To characterize the clinicopathologic features of these patients we performed histopathologic studies, direct and indirect immunofluorescence, immunoelectron microscopy (patient 2), and immunoprecipitation of both patients' serum. Histopathologic examination revealed a moderate eosinophilic infiltrate partly arranged along the basement membrane zone and focally invading the epidermis. Linear deposits of immunoglobulin and C3 along the dermoepidermal junction were localized within the lamina lucida and over the hemidesmosomal plaques. Immunoprecipitation revealed the presence of circulating autoantibodies against the 230 kd bullous pemphigoid antigen. These findings suggest that our patients had a distinct, nonbullous variant of the pemphigoid spectrum.
Aged↗
Statistical evaluation of epiluminescence microscopy criteria for melanocytic pigmented skin lesions.
BACKGROUND: Epiluminescence microscopy (ELM) is a noninvasive technique by which the clinical diagnosis of pigmented skin lesions (PSL) can be improved. Many ELM criteria have been described, but their significance in the differential diagnosis of PSL has not yet been established. OBJECTIVE: The purpose of this study was to determine the value of ELM criteria in the differential diagnosis of PSL. METHODS: Two hundred one melanocytic PSL (61 common nevi, 60 dysplastic nevi, and 80 melanomas) were investigated with ELM for the presence of certain ELM criteria; their significance was determined by calculating the odds ratios. RESULTS: Individual ELM criteria have different weights of significance in the differential diagnosis of melanocytic PSL. Selected patterns of ELM criteria adjusted to the distinct types of PSL considerably improve the diagnostic accuracy of melanocytic PSL. CONCLUSION: The prevalence of certain distinct ELM criteria in a given melanocytic PSL has statistical value in differential diagnosis.
Confidence Intervals↗