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Biomedical subjects

A W Kopf

Publications and source records attributed to A W Kopf.

At least 37 records · Page 2Linked to original sources
PubMed2000

Precision of automatic measurements of pigmented skin lesion parameters with a MelaFind(TM) multispectral digital dermoscope.

The purpose of this study was to assess the precision of automatic computerized measurement of parameters that may be useful in the differentiation of malignant melanoma from benign pigmented skin lesions, and also to determine the feasibility of quantitative monitoring of skin lesions over time. Ten independent sequences of images were acquired with a MelaFind multispectral digital dermoscope for each of 12 benign or malignant pigmented skin lesions. The sequences of images were processed automatically to provide 10 independent measurements of the various parameters for each lesion. Parameters included lesion area, greatest 'diameter', perimeter, reflectance and asymmetry. The precision of each parameter determination was computed from the mean and standard deviation of the 10 measurements of that parameter. The relative errors in determining the lesion area, 'diameter' and perimeter were found to be 6%, 3% and 4%, respectively. Other lesion parameters that are used in differentiating melanomas from benign skin lesions were also analysed as a function of wavelength. In the blue band (about 430 nm) the relative error was about 7% for the mean lesion reflectance and about 7% for the asymmetry parameter. These results demonstrate the feasibility of using MelaFind for objective quantitative monitoring of changes in pigmented skin lesions over time. As suggested by some studies, such information is useful in the early detection of malignant melanoma. The results show that parameters obtained automatically from MelaFind images are sufficiently precise to allow pertinent parameters to be used to classify pigmented skin lesions.

Databases, Factual↗
PubMed2000

Large congenital melanocytic nevi and the risk for development of malignant melanoma and neurocutaneous melanocytosis.

OBJECTIVE: To determine the risk for developing malignant melanoma and neurocutaneous melanocytosis (NCM) in patients with large congenital melanocytic nevi. DESIGN: Follow-up data suitable for calculations were available on 160 patients in the New York University Registry of Large Congenital Melanocytic Nevi who had been free of known melanomas or NCM when entered into the Registry. The cumulative 5-year life-table risks for developing melanoma and NCM were calculated. The relative risk for developing melanoma, using a control general population reference group, was determined. RESULTS: The 160 patients (median age at entry: 14 months) were followed prospectively for an average of 5.5 years. Three extracutaneous melanomas developed: 2 were in the central nervous system (CNS) and 1 was retroperitoneal. The 5-year cumulative life-table risk for developing melanoma was 2.3% (95% confidence interval [CI]:.8-6.6) and the relative risk was 101 (95% CI: 21-296). No melanoma occurred within a large congenital melanocytic nevus. Four patients developed manifest NCM, 2 with CNS melanomas. The 5-year cumulative life-table risk for developing NCM was 2.5% (95% CI:.8-7.2). Ten patients were excluded from the calculations because of preexisting disease on entry into the Registry: 5 with manifest NCM and 5 with melanomas (3 in large congenital melanocytic nevi, 1 in nonnevus skin, and 1 unknown primary). CONCLUSIONS: Patients with large congenital melanocytic nevi are at increased risk for developing melanomas. There is also a significant increased risk for developing NCM. The high incidence of CNS involvement may influence decisions concerning treatment of the large congenital melanocytic nevi.

Adolescent↗
PubMed1998

Risk of melanoma in medium-sized congenital melanocytic nevi: a follow-up study.

BACKGROUND: The risk of the occurrence of malignant melanoma (MM) in medium-sized (1.5 to 19.9 cm in diameter) congenital melanocytic nevi (CMN) is the subject of controversy. Universally accepted recommendations regarding the management of such lesions have not been made. OBJECTIVE: Our purpose was to assess the risk of MM arising in medium-sized CMN. METHODS: The study included 230 medium-sized CMN in 227 patients, first seen in a private dermatology practice from 1955 to 1996, who were followed up for MM arising within their CMNs. Criteria for entry into the study included (1) a clinically diagnosed medium-sized CMN, (2) minimum follow-up period of 1 year, and (3) a photograph of the lesion in the patient's medical record. RESULTS: No MM occurred in a medium-sized CMN during an average follow-up of 6.7 years (median, 5.8 years) to an average age of 25.5 years (median, 19.1 years). CONCLUSION: The results of this short-term follow-up study do not support the view that there is a clinically significantly increased risk for MM arising in banal-appearing medium-sized CMN or that prophylactic excision of all such lesions is mandatory. Lifelong medical observation seems a reasonable alternative for many medium-sized CMN.

Adolescent↗
PubMed1998

Laboratory tests and imaging studies in patients with cutaneous malignant melanoma.

Laboratory tests and imaging studies are often ordered for asymptomatic patients with malignant melanomas (MMs) in an effort to detect subclinical metastatic disease. However, their sensitivity and specificity for detecting cryptic metastases are not well established. A review of the literature on laboratory tests and imaging studies for MM metastases was undertaken to address the usefulness of such investigations in asymptomatic patients with MM in AJCC (American Joint Committee on Cancer system of classification) stages I, II, and III. A review of the pertinent literature since 1966 was conducted through MEDLINE, Medica, and Cancerlit. Laboratory tests and imaging studies revealed occult MM metastases in only a small number of the thousands of reported patients with putative AJCC stage I, II, and III MM. However, for those diagnosed with limited metastases, surgical removal with or without immunotherapy, chemotherapy, or radiotherapy can lead to long-term remissions in some patients. For patients with asymptomatic AJCC stage I or II disease, chest roentgenograms (CXR) and blood lactic dehydrogenase (LDH) levels may be obtained at low cost and prove to be of benefit if metastases are identified. For patients with AJCC stage III disease, computed tomographic (CT) scans of the thorax, abdomen, and pelvis (especially when the primary cutaneous site of the melanoma is below the waist) may be considered for detecting metastatic MM. Other tests, such as magnetic resonance imaging (MRI) scans of the brain, may be ordered based on symptoms or physical findings. In the future, technologically improved techniques and newer methods may prove cost-effective for detecting treatable asymptomatic MM metastases. Furthermore, improvement in treatments will also influence the indications for the search for occult MM metastases. At this time there is a need for an international consensus conference on laboratory tests and imaging studies for occult melanoma metastases.

Clinical Chemistry Tests↗
PubMed1998

Comparison of conventional photographs and telephonically transmitted compressed digitized images of melanomas and dysplastic nevi.

BACKGROUND: One of the most difficult problems in the in vivo diagnosis of cutaneous tumors is the differentiation clinically between early malignant melanoma (MM) and atypical (dysplastic) melanocytic nevi (AMNs) because these lesions share clinical features. High-quality digital imaging systems and store-and-forward technology have the potential for use in a teledermatology system with which experts would be able to immediately transmit their diagnostic opinions concerning these challenging lesions. OBJECTIVE: The main purpose of this study was to determine if the clinical and dermoscopic diagnoses and the dermoscopic features of AMN and early MM are unaltered after telephonic transmission of their digitized images. METHODS: Conventional and dermoscopic photographic transparencies of 22 AMNs and 9 early MMs, viewed on rearview projectors and then scanned, compressed, transmitted (Internet) and viewed on color monitors, were evaluated. RESULTS: The concordance in the diagnosis of AMN and of early MM by all four observers, both clinically and dermoscopically, when comparing rearview-projected conventional transparency slides to transmitted, compressed, digitized images, was high. For most specific dermoscopic features, the concordance was good, although less so for the presence or absence of some dermoscopic creatures, namely 'dots', 'blue/gray' color and 'red' color. CONCLUSION: The results reported support the conclusion that Internet transmission of digitized images of MMs and AMNs retains sufficient information for diagnostic purposes. This study is a step in the creation of an international teledermoscopy network for pigmented cutaneous lesions.

Computer Communication Networks↗
PubMed1997

Predicting ten-year survival of patients with primary cutaneous melanoma: corroboration of a prognostic model.

BACKGROUND: Recently, the Pigmented Lesion Group at the University of Pennsylvania described a 4-variable model for predicting 10-year survival for patients with primary cutaneous melanoma. The variables are tumor thickness, anatomic site of the lesion, age, and gender. The objective of the current study was to test the validity of this model, employing the large data base of the New York University Melanoma Cooperative Group. METHODS: The predicted probabilities of 10-year survival for 780 patients with primary cutaneous melanoma were determined by multivariate logistic regression, using the 4 variables. RESULTS: The overall 10-year survival rate of the current study group was 78.4%. Of the four variables, tumor thickness, anatomic site of the lesion, and age were found to be independent predictors of survival. Although survival was better for women, gender was not a statistically significant factor in predicting 10-year survival when entered into the multivariate logistic regression model. In the current study, the probability of 10-year survival of patients with melanomas < 0.76 mm ranged from 93-99%, depending on the age and primary site. Age and site had more impact on the prognosis of intermediate and thick melanomas than on thin melanomas. Thus, for melanomas 0.76-1.69 mm, 1.70-3.60 mm, and thicker than 3.60 mm, the probabilities of survival ranged from 70-94%, 39-82%, and 23-68%, respectively. CONCLUSIONS: The wider ranges in survival rates for thicker melanomas, depending on the other variables, emphasize the importance of including variables in addition to tumor thickness in a prognostic model. Using a large data base from a medical center, the current study supports the prognostic multivariate model of the Pigmented Lesions Group of the University of Pennsylvania; however, the authors of the current study did not find gender to be statistically significant in this multivariate model.

Adolescent↗
PubMed1997

A study of large congenital melanocytic nevi and associated malignant melanomas: review of cases in the New York University Registry and the world literature.

BACKGROUND: Patients with large congenital melanocytic nevi (LCMN) are at greater risk for the development of malignant melanoma (MM) than are persons in the general population. OBJECTIVE: Our purpose was to identify the clinical features of LCMN in those patients in whom MMs actually developed. METHODS: The records of 117 patients in the New York University Registry of LCMN and the reports of 172 cases of LCMN in the world literature were studied. RESULTS: Of the 289 cases of LCMN studied, 34 patients (12%) had primary cutaneous MMs within their nevi; in two additional patients, MMs developed at cutaneous sites other than within their nevi. All patients in whom MM developed within LCMN had nevi in axial locations; however, 91% of the LCMN were axial. No MM was found that had arisen in any of the 26 LCMN confined to the extremities. In addition, no MM was found that had arisen in thousands of satellite nevi. CONCLUSION: When MM develops within an LCMN, it generally does so in those LCMN in an axial location. The absence of cases of MM arising in LCMN confined to the extremities suggests that such nevi represent lower risk lesions, but the number of extremity nevi analyzed was too small to allow definitive conclusions. A striking finding was the absence of MMs arising in satellite nevi.

Humans↗
PubMed1997

Laboratory tests and imaging studies in patients with cutaneous malignant melanomas: a survey of experienced physicians.

BACKGROUND: The presence or absence of metastases is important in determining prognosis and treatment options for patients with malignant melanoma (MM). Laboratory tests and imaging studies are ordered for patients with MMs but without symptoms in an effort to detect occult metastases. However, which laboratory tests and imaging studies to order and how often to reorder them is not well established. OBJECTIVE: Our purpose was to determine which tests and studies are ordered by physicians with major responsibilities for the care of patients with MM. METHODS: Physicians were surveyed by questionnaire about the laboratory tests and imaging studies they ordered for MM stages 0, I, II, and III. RESULTS: Of the 35 physicians queried, 30 (86%) responded to the survey. The majority of physicians order tests as follows: no tests for MM in situ; roentgenography of the chest with or without initial lactic acid dehydrogenase/liver function tests for stages I, II, and III and during follow-up for stages IB, II, and III (more frequently as the Breslow thickness increases); and baseline computed tomographic or magnetic resonance imaging scans of the chest, abdomen/pelvis, and brain for stage III. CONCLUSION: Although the pattern of ordering examinations was similar for the majority of respondents, there was significant variability among experienced physicians in ordering laboratory tests and imaging studies in the search for occult metastases in patients with asymptomatic MM. The laboratory tests and imaging studies ordered and their frequency depend on the stage of the MM and sometimes on other risk factors.

Clinical Laboratory Techniques↗
PubMed1996

The incidence of malignant melanoma in the United States: issues as we approach the 21st century.

The risk of malignant melanoma developing in an American in the United States has now reached 1 in 87 (up more than 1800% since the 1930s). This rising incidence of malignant melanoma is, in fact, real because (1) it is not due to increased surveillance; (2) it is not due to better cancer-counting methods in general; (3) it is not due to changes in histologic diagnostic criteria; (4) it is being noted worldwide; and (5) most importantly, despite rising survival percentages, the mortality rate from malignant melanoma also continues to rise. On the basis of these trends, incidence rates for malignant melanoma will continue to rise for at least the next 10 to 20 years, although the demographics of those affected may change. Effective programs to improve public and professional education must be developed to enhance early clinical detection and behavioral changes. An establishment of a National Melanoma Registry is needed to more effectively assess the magnitude and impact of future incidence and the success of prevention program efforts into the next century.

Adult↗
PubMed1996

Neurocutaneous melanosis: clinical features of large congenital melanocytic nevi in patients with manifest central nervous system melanosis.

BACKGROUND: Patients with a large congenital melanocytic nevus (LCMN) may have associated leptomeningeal melanocytosis with or without central nervous system (CNS) melanomas. These patients are considered to have neurocutaneous melanosis, a disorder that, when symptomatic or otherwise manifest neurologically, carries a poor prognosis even in the absence of malignancy. OBJECTIVE: Our purpose was to identify typical clinical features in patients who have manifest CNS melanosis in association with LCMN. METHODS: The records of 117 patients with LCMN in the New York University Registry of LCMN and the reports of 172 cases of LCMN in the world literature were included for features that might signal a high risk for the development of manifest CNS involvement. RESULTS: Of the 289 patients with LCMN, 33 had manifest CNS melanosis. In all 33 in whom symptomatic neurocutaneous melanosis was diagnosed, the LCMNs were present in a posterior axial location on the head, neck, back, and/or buttocks. "Satellite" nevi were known to be present in 31 of the 33 patients. CONCLUSION: Patients with LCMN in a posterior axial location, especially when associated with "satellite" melanocytic nevi, are at greater risk for the development of manifest neurocutaneous melanosis than patients with LCMN limited to the extremities or those who are lacking satellite nevi.

Adolescent↗