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Biomedical subjects

A C Halpern

Publications and source records attributed to A C Halpern.

At least 37 records · Page 2Linked to original sources
PubMed1999

Genetic predisposition to skin cancer.

Here we review recent insights in the genetics of skin cancer susceptibility as gleaned from studies of three hereditary syndromes: basal cell nevus syndrome, familial melanoma/dysplastic nevus syndrome, and xeroderma pigmentosum. We provide a brief synopsis of the recent findings related to these syndromes in an attempt to illustrate several emerging themes in the genetics of skin cancer. These themes include 1) the recent identification of multiple cancer susceptibility genes that occur in a myriad of cellular regulatory pathways; 2) the relative specificity of certain regulatory pathways to the development of specific types of cancer; and 3) the important role of DNA damage caused by ultraviolet radiation and defective DNA repair mechanisms in the development of skin cancer. We also review the implications of this knowledge to clinical practice relative to risk assessment, primary prevention, and therapy.

Basal Cell Nevus Syndrome↗
PubMed1999

Evaluation of factors associated with skin self-examination.

Early detection and excision of thin lesions may be important in reducing mortality from melanoma. Periodic skin self-examination may be beneficial in identifying thin lesions. The purpose of this study was to evaluate factors associated with skin self-examination. The study population was comprised of 549 Caucasian residents of Connecticut 18 years of age or older who were selected as controls as part of a population-based case-control study on skin self-examination and melanoma conducted during 1987-1989. Personal interviews were conducted to obtain information on skin self-examination, demographics, history of cancer, phenotypic characteristics, sun exposure habits, and screening and health behaviors. Nevus counts were performed by trained nurse interviewers. Logistic regression was used to model the relationship between the variables of interest and skin self-examination. Female gender was identified a priori as a predictor of skin self-examination, and thus all analyses were stratified by gender. Age, education, and marital status were also identified a priori as important predictor variables and were selected for inclusion in the final models. Skin awareness was a strong factor associated with skin self-examination for both females and males. For females, previous benign biopsy or the presence of an abnormal mole was identified as important for future skin self-examination using our criteria. A family history of cancer, physician examination, and change in diet to reduce cancer risk increased the likelihood of skin self-examination in males but not females. In women, light hair color may increase the likelihood of performing skin self-examination. Older age and college or postgraduate education was associated with a decreased likelihood of performing skin self-examination in both males and females. Identifying factors associated with skin self-examination will enable health care providers to target individuals who may not be performing skin self-examination but who are at increased risk for developing melanoma.

Adolescent↗
PubMed1998

Validation of a melanoma prognostic model.

BACKGROUND: A "clinically accessible," 4-variable (patient age, patient sex, tumor location, and tumour thickness) prognostic model has been published previously. This model evaluated variables that were commonly available to the clinician. Because models are heuristic, validity of a prognostic model should be evaluated in a population different from the original population. OBJECTIVE: To evaluate the external validity of this 4-variable melanoma prognostic model. DESIGN: To estimate the external validity of this model, we used a population-based cohort of individuals with melanoma. We also evaluated a 1-variable model (tumor thickness). Estimates of the external validity of these logistic regression models were made using the c statistic and the Brier score. SETTINGS AND PATIENTS: A total of 1261 patients with melanoma evaluated in a multispecialty, university-based practice and 650 patients with melanoma from throughout Connecticut. MAIN OUTCOME MEASURE: Death from melanoma within 5 years of diagnosis. RESULTS: The c statistics for the 4-variable model were 0.86 (95% confidence interval [CI], 0.83-0.89) for the university-based practice data set and 0.81 (95% CI, 0.75-0.86) for the Connecticut data set. For thickness alone, the c statistics were 0.83 (95% CI, 0.80-0.86) and 0.79 (95% CI, 0.74-0.85), respectively. Brier scores for the 4-variable model were 0.09 (95% CI, 0.08-0.10) and 0.08 (95% CI, 0.06-0.09) and for the 1-variable model were 0.09 (95% CI, 0.08-0.10) and 0.08 (95% CI, 0.07-0.10), respectively. No significant differences exist between the data sets for the 4- and 1-variable models. CONCLUSIONS: The 4- and 1-variable models are generalizable. The simpler 1-variable model--tumor thickness--can be used with a relatively small loss in accuracy.

Female↗
PubMed1998

Cutaneous melanoma risk and phenotypic changes in large congenital nevi: a follow-up study of 46 patients.

BACKGROUND: Large congenital melanocytic nevi may undergo malignant transformation. Few prospective studies have evaluated the incidence of melanoma in large congenital nevi or have described how their phenotypic characteristics change over time. OBJECTIVE: We attempted to ascertain the incidence of cutaneous melanoma in a cohort of patients with large congenital nevi and to evaluate the frequency and nature of several morphologic changes over time. METHODS: Forty-six patients with large congenital nevi were prospectively followed up in our Pigmented Lesion Group. Large congenital nevi were defined as those occurring at birth and comprising 5% body surface area or greater in infants, children, and preadolescents and more than 20 cm in adolescents and adults. Information was obtained on location, satellitosis, changes in color and nodularity, and incidence of melanoma. The most atypical histologic findings from those who underwent biopsy were also noted. Standardized morbidity ratios (SMR) and 5-year cumulative risk were calculated and presented with corresponding 95% confidence intervals (CI). RESULTS: Twenty-four male and 22 female patients (age range, 7 days to 36.7 years; mean, 8.4 years) with large congenital nevi were followed up prospectively for a total of 335 person-years (range, 0.17 to 17.5 person-years; mean, 7.3 person-years). Two patients (4.3%) experienced 3 cutaneous melanomas that originated in their primary congenital nevi. We found one case of neurocutaneous melanosis. No satellite, extremity, or extracutaneous melanomas were detected. The majority of nevi in our cohort were located on the posterior trunk, were accompanied by multiple satellite congenital nevi, and became lighter over time. In the 27 patients who underwent biopsies, the most atypical histologic findings included melanoma, atypical melanocytic dysplasia, neurocristic dysplasia, atypical neural crest hamartomas, atypical spindle cell tumors, and congenital nevi with dysplasia. The SMR comparing observed-to-expected melanoma incidence was 148 (95% CI 18, 535; P = .0002) indicating a substantially increased risk of melanoma in patients with large congenital nevi. The cumulative 5-year risk of cutaneous melanoma was 5.7% (95% CI 0%, 13.5%). CONCLUSION: Our findings are consistent with the previously observed increased risk for the occurrence of cutaneous melanoma in patients with large congenital nevi. Although the number of patients with melanoma in this study is small, our observations and those of previous studies suggest that location and age correlates with melanoma risk. The majority of large congenital nevi are located on the trunk and may undergo several clinical changes as these patients age. Additional prospective studies are needed to gain more insight into the natural history and optimal management of large congenital nevi.

Adolescent↗
PubMed1998

Hormonal influences on women with psoriasis.

Various endogenous factors such as stress and infection are known to influence psoriasis. Previous data suggest that pregnancy has a significant influence on the course of psoriasis. This study explores the effect of pregnancy as well as other hormonal events on psoriasis in women.

Adolescent↗
PubMed1997

Melanoma of unknown primary site: presentation, treatment, and prognosis--a single institution study. University of Pennsylvania Pigmented Lesion Study Group.

BACKGROUND: A retrospective analysis of 40 patients diagnosed with melanoma of unknown primary site (MUP) was undertaken to analyze the etiology and clinical behavior of this presentation. METHODS: The patient records were located by a computer search of the Pigmented Lesion Clinic data base at the University of Pennsylvania. With the Cox proportional hazards model, the survival of the MUP patients with lymph node presentation was compared with that of patients with lymph node disease and a known concurrent primary melanoma. RESULTS: Sixty-five percent of the patients presented with lymph node metastasis only, 28% presented with visceral lesions, and 8% presented with subcutaneous nodules. The prevalence of dysplastic nevi was 22.5%. The overall 4-year survival rate for the 40 MUP patients was 55% +/- 9%. The 4-year survival (57% +/- 12%) of patients with lymph node presentation was compared with that of patients presenting with lymph node disease and a known concurrent primary melanoma (19 +/- 6%). Survival was significantly different between the groups (P = 0.008). This survival difference remained significant (P = 0.02) even after adjustments for number of positive lymph nodes, year of diagnosis, and age at diagnosis. CONCLUSIONS: This analysis revealed that MUP patients with lymph node metastasis survived significantly longer than patients diagnosed with lymph node metastasis concurrent with a known cutaneous primary melanoma. The prevalence of dysplastic nevi in the MUP patient series was intermediate between that reported among primary melanoma patients and that reported among population controls, suggesting the likelihood of a primary cutaneous origin for the metastatic melanoma.

Adult↗
PubMed1997

Prognostic models in melanoma.

Predicting which patients with primary melanoma are at risk of developing metastastic disease is important for making rational therapeutic decisions. Tumor thickness alone is the most commonly used predictor of survival, but other clinical and pathologic variables also play an important role. We have developed two multivariate logistic regression models to predict survival in patients who have primary melanoma. The first of these models assigns patients to two groups based on radial or vertical growth phase. The probability of survival for those patients with vertical growth phase tumors was further determined based on a model using six variables (mitotic rate, tumor infiltrating lymphocytes, tumor thickness, anatomic site of the primary tumor, sex, and histologic regression) that have the greatest strength as independent predictors of survival. This model is 89% accurate for predicting survival in patients with vertical growth phase tumors. A second model has been developed that uses readily available clinical parameters to predict survival. Four variables (tumor thickness, anatomic site, age, and sex) entered into the model as powerful independent predictors. Clinical algorithms for assessing patient risk are provided.

Age Factors↗
PubMed1996

A prognostic model for predicting 10-year survival in patients with primary melanoma. The Pigmented Lesion Group.

OBJECTIVE: To develop a prognostic model, based on clinical and pathologic data that are routinely available to the clinician, that would estimate the chance for survival of a patient with primary cutaneous melanoma after definitive surgical therapy. DESIGN: Cohort analytical study. SETTING: University medical center. PATIENTS: 488 patients with primary cutaneous melanoma who had no apparent metastatic disease. Patients were followed prospectively for at least 10 years. An independent validation sample of 142 patients was used to assess the stability of the model. MEASUREMENTS: Six clinical and pathologic variables that predict survival and are readily available to the clinician were used to develop a prediction model. The variables were tested for their association with death by using a univariate logistic regression model. Point estimates were generated for the probability of surviving melanoma at 10 years. Variables that were statistically significantly associated with survival were retained for testing in a logistic regression model. RESULTS: 488 patients were followed prospectively for a median of 13.5 years (minimum, 10.0 years; maximum, 20.5 years). The overall 10-year survival of the study group was 78%. Four variables were found to be independent predictors of survival. Presented as adjusted odds ratios, from strongest to weakest relative predictive strength, these variables were tumor thickness (odds ratio, 50.8), site of primary melanoma (odds ratio, 4.4), age of the patient (odds ratio, 3.0), and sex of the patient (odds ratio, 2.0). The four-variable model was significantly more accurate than tumor thickness alone, particularly for predicting death. Overall, use of the model reduced the error rate of the prediction of death by 50%. CONCLUSIONS: A prognostic model that uses four readily accessible variables more accurately predicts outcome in patients with primary melanoma than does tumor thickness alone. This four-variable model can identify patients at high risk for the recurrence of disease, an identification that becomes increasingly important as adjuvant therapies are developed for treatment of melanoma.

Adult↗
PubMed1996

Eczematous halo reaction in atypical nevi.

Meyerson's nevus has been described as a melanocytic nevus with an associated eczematous halo reaction. We describe four patients with eczematous halos developing around atypical nevi, a finding not previously reported. Biopsy specimens revealed eosinophilic spongiosis in addition to the previously reported spongiotic dermatitis.

Adult↗
PubMed1996

Melanoma-associated expression of transforming growth factor-beta isoforms.

Melanocytic neoplasia is characterized by the aberrant overproduction of multiple cytokines in vitro. However, it is largely unknown how cytokine expression relates to melanoma progression in vivo. Transforming growth factor beta (TGF-beta) is a multifunctional cytokine commonly produced by cultured melanoma cells. The in situ expression of all three TGF-beta isoforms (TGF-beta1, -2, and -3) was determined immunohistochemically in melanocytes and in 51 melanocytic lesions using isoform-specific antibodies. Significant linear trends of expression were observed from melanocytes through nevi and primary and metastatic melanomas for all three isoforms. TGF-beta1 was expressed by some melanocytes and almost uniformly by nevi and melanomas. TGF-beta2 and -3 were not expressed in normal melanocytes but were expressed in nevi and early and advanced primary (radial and vertical growth phase) and metastatic melanomas in a tumor-progression-related manner. TGF-beta2 was heterogeneously expressed in advanced primary and metastatic melanomas, whereas TGF-beta3 was uniformly and highly expressed in these lesions. Thus, expression of TGF-beta isoforms in melanocytes and melanocytic lesions is heterogeneous and related to tumor progression, and expression of TGF-beta2 and TGF-beta3 commences at critical junctures during progression of nevi to primary melanomas.

Biomarkers, Tumor↗
PubMed1994

Effects of topical tretinoin on dysplastic nevi.

PURPOSE: As potential precursors of melanoma and markers of increased melanoma risk, dysplastic nevi are suitable targets of strategies for melanoma chemoprevention. We report the results of a pilot study of topical retinoic acid in patients with dysplastic nevi. PATIENTS AND METHODS: Five male patients with dysplastic nevi applied tretinoin to half of the back for 6 months. Baseline photographs of dysplastic nevi were compared with posttreatment photographs and assessed for morphologic change. At study completion, each subject had four nevi excised from the treated side and four from the untreated side of the back. Biopsies were histologically evaluated for the presence of dysplasia. RESULTS: All patients developed signs of irritation as a result of treatment. One patient was not compliant with treatment due to skin irritation. The four compliant patients showed significant decreases in the clinical atypia of treated lesions, with concomitant fading and even disappearance of many treated nevi. Histologically, only four of 16 treated nevi met histologic criteria for dysplasia, in comparison to 13 of 16 untreated nevi. CONCLUSION: These results suggest that there is concomitant clinical and histologic improvement in a significant percentage of dysplastic nevi treated with topical tretinoin. However, the utility of topical tretinoin for chemoprevention of melanoma is limited by difficulty of application and associated inflammation. While new strategies in chemoprevention of melanoma are explored, sun protection and assiduous avoidance of sunburn must remain the mainstay of melanoma prevention.

Administration, Topical↗
PubMed1993

Natural history of dysplastic nevi.

BACKGROUND: Dysplastic nevi are markers of melanoma risk and potential precursors of melanoma. Few studies have addressed the natural history of dysplastic nevi. OBJECTIVE: Our purpose was to describe the changes observed in nevi over time in a cohort of our patients with dysplastic nevi. METHODS: We used a historical cohort design to study 153 patients with dysplastic nevi observed for a minimum of 5 years. Physical examination at completion of the study was compared with baseline overview and close-up photographs. Lesions excised during the study interval were assessed for history of change. RESULTS: Fifty one percent of all evaluated nevi (297 of 593) showed clinical signs of change during an average follow-up of 89 months. New nevi were common in adulthood and continued to form in more than 20% of patients older than 50 years of age. Nevi were observed to become more clinically atypical, less clinically atypical, and disappear in all age groups. In this small cohort rates of nevus change were not correlated with personal or family history of melanoma, sex, or total number of nevi. Total nevus counts and rates of nevus change were correlated with age. CONCLUSION: Dysplastic nevi remain clinically dynamic in adulthood. Our data suggest that the decrease in counts of dysplastic nevi associated with increasing age is only partly explained by the disappearance of nevi over time and probably reflects a tendency to larger numbers of nevi among more recent birth cohorts.

Adolescent↗
PubMed1993

Growth regulation of cultured human nevus cells.

Cells isolated from congenital melanocytic nevi and cultured in vitro have growth characteristics that resemble their premalignant stage in situ. A serum-free, chemically defined medium has been developed that allows continuous growth of established nevus cultures for up to several months. Like primary melanoma cells, nevus cells in high-calcium-containing W489 medium require insulin for growth. In contrast to melanoma cells, nevus cells in serum-free medium require the presence of alpha-melanocyte-stimulating hormone, which enhanced intracellular levels of cyclic adenosine monophosphate. In contrast to the requirements of normal human melanocytes from newborn foreskin, congenital nevus cells grow with less dependency on basic fibroblast growth factor (bFGF). Nevus cultures contain bFGF-like activity, and they express bFGF mRNA. Nevic cells of compound nevi also express bFGF mRNA in situ but only in the junctional areas. These results indicate that bFGF plays an important growth regulatory role for nevus cells in vitro and in vivo.

Base Sequence↗
PubMed1993

A cohort study of melanoma in patients with dysplastic nevi.

A historical cohort of 153 patients with dysplastic nevi was studied for the development of melanoma. Each subject had a minimum follow-up of 5 years, with an average study follow-up of 94 months. Eleven new melanomas developed in 11 patients between 11 and 143 months (average 61 months) into the study period. Age-adjusted melanoma incidence in the cohort was 692/100,000 person years. Development of melanoma was strongly correlated with prior personal and/or family history of melanoma. Even among the 89 patients with no personal or family history of melanoma, the age-adjusted incidence of melanoma was an alarming 154/100,000 person years. Within this small, non-randomly ascertained cohort no association could be discerned between melanoma incidence and total number of banal or dysplastic nevi. These findings support the public health significance of the recognition of dysplastic nevi and confirm the importance of family history in evaluating melanoma risk associated with dysplastic nevi.

Adolescent↗
PubMed1993

The early and intermediate precursor lesions of tumor progression in the melanocytic system: common acquired nevi and atypical (dysplastic) nevi.

Intermediate lesions of melanocytic tumor progression are potential precursors, simulants, and risk markers of melanoma. The clinical, public health, and biologic significance of intermediate lesions warrants their continued recognition and study, although improved schemata for their clinical and histological coding are needed. Blurred boundaries are inherently problematic to the categorization of lesions occurring along a stepwise pathway of increasing clinical and histological atypia. Nevertheless, the concepts of melanocytic dysplasia and of radial growth phase (in situ and microinvasive) melanoma are important to the classification of intermediate lesions of melanocytic tumor progression. Conceptually, these lesions are clearly separable from early and late lesions and from one another, and there is evidence that criteria distinguishing them can be reproducibly applied. Analysis of these intermediate lesions suggests that they represent responses to events (perhaps mutational) induced by ultraviolet light in constitutionally hypersensitive individuals, supporting epidemiological data that implicate sunlight as an etiologic agent for most melanomas. The continuing rigorous application of the methodologies of epidemiology and basic science to the study of these lesional steps will likely lead to the recognition of biologic markers to better distinguish benign from malignant melanocytic lesions.

Adult↗
PubMed1991

Using a claims database to investigate drug-induced Stevens-Johnson syndrome.

In order to explore a priori hypotheses about drug-induced Stevens-Johnson Syndrome (SJS), a case-control study was initiated using data from COMPASS, a computerized data base consisting of Medicaid claims data. The records of 3.8 million patients in five U.S. states were searched to identify patients with an inpatient diagnosis of ICD-9-CM code 695.1 (erythema multiforme-EM). Out of the total of 367 cases that were identified, primary medical records for 249 were sought and 128 (51.4 per cent) of these were obtained. The remainder could not be obtained because: in 36 (29.8 per cent) the hospital refused to provide medical records; in 33 (27.3 per cent) there were transcription errors; in 20 (16.5 per cent) the state could not translate the identification number, primarily because the patients lost Medicaid eligibility too long before our request; in 27 (22.3 per cent) the hospital could not locate the patient's record; and in 5 (4.1 per cent) there were other reasons. Of those with a medical record, 121 (94.5 per cent) had a skin diagnosis and 109 (85.2 per cent) had a diagnosis compatible with ICD-9-CM code 695.1 specified on their discharge summary. However, in 35 (27.3 per cent) an expert reviewer felt that the discharge diagnosis was incorrect. In 50 (39 per cent) the computer diagnosis was incorrect. Only 19 (14.8 per cent) were judged by the expert reviewer to truly have Stevens-Johnson Syndrome, and an additional 37 (28.9 per cent) were judged to have erythema multiforme minor. Thus, the computerized diagnosis agreed very well with the diagnoses specified on the discharge summary. However, EM is frequently misdiagnosed, ICD-9-CM code 695.1 contains multiple other diagnoses which are not EM, and much of hospitalized EM is EM minor. Thus, studies of SJS cannot be performed except in patients whose medical records are available.

Adolescent↗