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M Berwick

Publications and source records attributed to M Berwick.

At least 55 records · Page 3Linked to original sources
PubMed1996

Nasopharyngeal cancer in a low-risk population: defining risk factors by histological type.

Nasopharyngeal cancer (NPC) is a major public health problem in parts of Southeast Asia and North Africa, but is rare among whites and blacks. Although infection with the EBV and genetic susceptibility appear to play large roles in high-incidence populations, migrant studies suggest that environmental factors may also be important. Aside from the high risks associated with ingestion of salted fish, surprisingly few other risk factors have been established from studies in endemic areas. We studied a low-incidence population to determine whether tobacco use, alcohol consumption, and certain medical conditions and treatments are related to NPC and to examine variations in risk by histology. We reasoned that new relationships might be best identified in the absence of strong causal pathways, such as intake of preserved foods and genetic susceptibility. A population-based case-control study was conducted from 1987 to 1993 at five cancer registries in the United States: western Washington, metropolitan Detroit, Connecticut, Iowa, and Utah. Controls were identified by random digit dialing and frequency matched to the gender and age distribution of cases at each registry. Telephone interviews were completed by 231 cases and 246 controls. We observed a strong dose-response relationship between cigarette smoking and risk of differentiated squamous cell carcinoma (test for trend, P < .001). The highest risk [odds ratio (OR), 6.5; 95% confidence interval (CI), 2.0-21.3] occurred among current smokers with a history of more than 60 pack-years. In contrast, there was no evidence that undifferentiated or nonkeratinizing carcinomas were associated with cigarette smoking. Similarly, a significant increase in risk was observed for the heaviest alcohol consumers (21 or more drinks/week) only for differentiated squamous cell carcinomas (OR, 2.9; 95% CI, 1.2-6.9). The associations with cigarettes and alcohol appeared to be stronger among persons 50 years or older. There was a suggestion that diagnosis with infectious mononucleosis (a marker of late infection with EBV) is linked with decreased NPC risk (OR, 0.4; 95% CI, 0.1-1.1). This report indicates that over two-thirds of differentiated squamous cell NPC cases arising in older persons in the United States can be accounted for by cigarettes and alcohol, but leaves unexplained cases arising in the young and carcinomas of undifferentiated or nonkeratinizing histology. Future studies of NPC need to take into account histology and age in evaluating these and other environmental and genetic risk factors.

Adult↗
PubMed1996

Associations between human leukocyte antigen type and nasopharyngeal carcinoma in Caucasians in the United States.

A genetic component to nasopharyngeal carcinoma (NPC) has been suggested by associations of the malignancy with human leukocyte antigens (HLAs) in Southern Chinese populations, among which NPC is a major cancer. Data from other races are inconclusive. We have investigated associations between NPC and HLA antigens at the HLA-A, B, C, and DQ loci and alleles at the DRB1 locus in a population-based, multicenter investigation in the United States. Data from 82 cases and 140 controls are presented, making this the largest study population analyzing data from Caucasians to date. HLA frequencies from study cases were also compared with external control groups from the 11th International Histocompatibility Workshop and the National Marrow Donor Program. Logistic regression methods were used to investigate the effects of the joint occurrence of multiple HLA types and to assay for differences in HLA-associated risk in different age groups. A meta-analysis was undertaken to compare and summarize our results with previously published findings. The meta-analysis found a protective association with A2 antigen in non-Chinese [odds ratio (OR), 0.63; P < 0.001], a protective association with A11 across all races (OR, 0.54; P < 0.001), and an increased risk associated with B5 in Caucasians (OR, 2.81; P < 0.001). The present study also found independent associations, in a logistic regression model, between NPC and DRB1*1501 (OR, 0.33), DRB1*0405 (OR, 7.57), and Cw3 (OR, 0.42), although these data must be interpreted cautiously due to multiple-testing considerations. Associations were found to be more pronounced in younger patients for A2, A11, A28, B8, and B51.

Adult↗
PubMed1995

Reliability of reported sunburn history in a case-control study of cutaneous malignant melanoma.

Reliability of reported sunburn history was assessed. Fifty cases and 50 controls were randomly selected from a population-based case-control study of skin examination practices and lethal melanoma in Connecticut. Eighty-two percent of these participants were interviewed from January 15, 1987, to May 15, 1989, and reinterviewed in 1990. The kappa coefficients ranged between 0.37 and 0.57; the intraclass correlation coefficients were similar and ranged between 0.34 and 0.69. There were no significant differences found by case-control status or sex for any variables, and the degree of disagreement was similar for cases and controls and could be considered free of recall bias.

Adult↗
PubMed1995

Increased thickness of pregnancy-associated melanoma.

The effects of pregnancy on the pathophysiology of melanoma remain unclear. Although a gender-specific advantage for women vs. men is seen for characteristics such as stage at presentation, site of primary tumour, and survival time, an adverse effect of pregnancy on melanoma development and progression has been reported. In a retrospective study, we investigated the tumour characteristics of women who developed pregnancy-associated melanoma, and compared them with melanomas arising in non-pregnant women of child-bearing age. The patient records of the Massachusetts General Hospital Pigmented Lesion Clinic were reviewed, and 465 women of reproductive age (16-45 years) who developed melanoma were identified. Of these, in 45 women (age 21-42 years) there was a close temporal relationship between diagnosis of the tumour and pregnancy. Clinical and histological characteristics of the primary tumours were recorded. Differences in tumour thickness, site and histological type were analysed. The mean thickness of pregnancy-associated melanomas was significantly greater than that of non-pregnancy-associated tumours (2.28 vs. 1.22 mm, respectively; P < 0.007). No differences in histological type (P = 0.64) or site (P = 0.74) of the primary tumours were found between the two patient groups. Not surprisingly, multivariate analysis revealed that tumour thickness was a statistically significant variable in determining prognosis (P = 0.001). An unexpected finding, on multivariate analysis, was a possible pregnancy-associated prognostic advantage (P = 0.08). Melanomas arising during pregnancy are thicker, but are not necessarily associated with a less favourable prognosis than tumours arising in non-pregnant women of child-bearing age.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1995

Tumor vascularity is not a prognostic factor for malignant melanoma of the skin.

Tumor vascularity has been proposed as a prognostic indicator for a number of solid tumors. Although a correlation between microvessel number and metastatic behavior has also been suggested for cutaneous melanoma, the small number of cases studied to date allows one to draw only preliminary conclusions. In this study, we have assessed tumor vascularity in cutaneous melanoma by comparing 60 cases of metastasizing and non-metastasizing tumors matched for tumor thickness, age, sex, and anatomic site. Ulex europaeus agglutinin I appeared to be the most suitable vascular marker for this study. Our results indicate that there was no statistically significant difference between the two groups with regard to tumor vascularity. Even after identifying 15 cases of thin ( < 1.0 mm thick) melanoma, there was no significant difference in the number of microvessels between metastasizing and non-metastasizing tumors. Comparison of patterns of vascular microarchitecture also failed to discriminate between the two groups. Thus, our results indicate that tumor vascularity may not be an independent prognostic factor for cutaneous melanoma.

Adolescent↗
PubMed1994

A protective association between the HLA-A2 antigen and nasopharyngeal carcinoma in US Caucasians.

Analyzing data from Caucasians participating in a multicentered population-based case-control study of nasopharyngeal carcinoma and HLA type in the US, we found persons with the A2 antigen to have a significantly lower risk than those with other antigens at the A locus [odds ratio (OR), 0.46; 95% confidence interval (CI), 0.21-0.96]. The protective association was stronger among presumptive homozygotes for A2. Similar results were obtained when cases were compared with US Caucasians typed either as part of the Collaborative Transplant Study, or by the 9th International Histocompatibility Workshop. These results are supported by a statistical summary of odds ratios for A2 from a number of previous studies in non-Chinese (summary OR, 0.69; 95% CI, 0.54-0.88). The odds ratio for patients with squamous-cell carcinomas was 0.56; among 7 patients with undifferentiated tumors the OR was 0.14. Results from in vitro studies of immune response to Epstein-Barr virus have found that the HLA-A2 antigen efficiently presents the EBV gene product LMP-2, which has been detected in NPC tumor cells. This offers a rationale for the observed protective association between the HLA-A2 antigen and nasopharyngeal carcinoma.

Antigen Presentation↗
PubMed1994

Malignant melanoma incidence in Connecticut (United States): time trends and age-period-cohort modeling by anatomic site.

This study examined time trends and age-period-cohort patterns in the incidence of cutaneous malignant melanoma (CMM) by gender and anatomic site in Connecticut (United States) between 1950 and 1989, using data from the population-based Connecticut Tumor Registry. A total of 8,249 invasive CMM incident cases were included. Cases were grouped into melanomas of the head and neck, upper limb, lower limb, and trunk. Between 1950 and 1989, rates increased substantially for all sites. The largest relative increases occurred in melanoma of the upper limb for both males and females; the largest absolute increase occurred for melanoma of the trunk in males; and the smallest increase occurred in head and neck melanoma in females. Recent trends for time periods 1970-89 among birth cohorts 1930-69 indicated that the rate of increase of CMM is slowing substantially among males, but not among females. Nevertheless, continued overall increases in CMM incidence are likely in Connecticut in the 1990s in both genders, with a decrease in the male-female ratio. The age-period-cohort patterns were significantly different between the genders and among anatomic sites, suggesting different trends in carcinogenic exposures (mainly ultraviolet radiation from the sun) or etiologic distinctions between males and females and among the sites.

Adult↗
PubMed1994

No improvement in survival from melanoma diagnosed from 1973 to 1984.

BACKGROUND: While the incidence and mortality of melanoma has increased dramatically during the last few decades, survival rates, based on the case-fatality ratio, have apparently improved. Efforts at early detection have probably been effective in the discovery of lesions at a curable stage. However, the effects of lead-time bias need to be accounted for in order to understand the contribution of early detection to the increased incidence. This can best be done by appropriately controlling for depth of the tumour or a surrogate of depth, at diagnosis. METHODS: A survival analysis was conducted for 3197 Connecticut residents newly diagnosed with invasive melanoma between 1973 and 1984. Five prognostic variables were evaluated: sex, age at diagnosis, anatomical site, histological type, and year of diagnosis. RESULTS: As expected, women and the young had better survival than men and the elderly. Melanomas located on the trunk had poorer prognosis than those on other sites. The survival experience by histological type was significantly different; lentigo maligna melanoma and superficial spreading melanoma had the best survival and nodular melanomas the poorest, while 'other' and unclassifiable melanomas had intermediate survival. When survival by period of diagnosis was controlled by other variables, which included surrogates for disease stage, there was no improvement in survival over time. CONCLUSION: These data do not imply that early diagnosis and treatment are ineffective; rather, that within stages of disease, survival improvements did not occur during the period 1973-1984.

Adolescent↗
PubMed1993

Histopathologic recognition and grading of dysplastic melanocytic nevi: an interobserver agreement study.

Before the controversies surrounding dysplastic melanocytic nevi are resolved, dermatopathologists must be able to reliably distinguish dysplastic nevi from common acquired nevi and malignant melanoma. To establish whether grading of melanocytic dysplasia has any biologic relevance, dermatopathologists must be able to consistently recognize two or more grades of atypia. We studied the concordance among five dermatopathologists for recognition and grading of 60 nevomelanocytic lesions. Ten cases from each of the following categories of melanocytic proliferation were retrieved from the Massachusetts General Hospital files: 1) common melanocytic nevi, 2) melanocytic nevi with features of dysplastic nevi, 3) dysplastic nevi with slight cytologic atypia, 4) dysplastic nevi with moderate cytologic atypia, 5) dysplastic nevi with severe cytologic atypia, and 6) primary malignant melanoma. The slides were reviewed independently; no discussion of diagnostic criteria preceded the review. Overall concordance for diagnosing dysplastic nevi was 77%, with a kappa statistic of 0.55-0.84. Furthermore, in grading dysplastic nevi, experienced dermatopathologists had a concordance ranging from 35% to 58% (kappa value 0.38-0.47). Those with less experience in grading dysplastic nevi had a concordance of 16-65% (kappa value 0.05-0.24). The five observers in this study reliably distinguished dysplastic nevi from common acquired nevi and malignant melanoma. Further refinement of the criteria for grading of nevo-melanocytic dysplasia and experience in grading are critical for accuracy in subcategorization of dysplastic nevi. Consistent, reproducible subcategorization of dysplastic nevi is a requisite before the issue of biologic or prognostic relevance of grading (dysplastic nevi) can be addressed. This study supports the validity of existing criteria for the diagnosis of dysplastic nevi because the problems in diagnosis were at the limits of the spectrum, namely, discrimination of slightly atypical dysplastic nevi from common nevi and severely atypical dysplastic nevi from radial growth phase melanoma.

Dysplastic Nevus Syndrome↗
PubMed1993

The effect of pre-education on patient compliance with full-body examination in a public skin cancer screening.

BACKGROUND: Public skin cancer screening has become increasingly common in recent years. However, currently there is no standardized procedure for these screenings. Full body skin examination as opposed to examination of sun-exposed areas offers several advantages, including the opportunity to diagnose early melanoma in areas normally covered by clothing. Disadvantages of full body skin examination include patient resistance because of inconvenience and concerns about privacy and modesty. The additional time involved in full body skin examination may also be an impediment. OBJECTIVE: In a randomized double-armed study, we studied whether patients were more likely to develop a positive attitude towards full body skin examination if they were advised beforehand, in writing, of the logic underlying the need for a complete examination. METHODS: Patients presenting to a public skin cancer screening were divided into two groups. Group A (N = 111) received a written explanation of the need for full body skin examination and Group B (N = 175) received no information. Patients were then surveyed, after the screening, about their attitudes towards full body skin examination. RESULTS: Those who received pre-education were less likely (P < .05) to be concerned about a genital examination. Those who were concerned about a genital exam were compared with those who were not concerned about a genital exam, the former patients were: 1) younger (P < .05); 2) more concerned about privacy (P < .001); and 3) preferred a physician of the same sex (P < .001). CONCLUSION: Providing patients with information about the need for full body skin examination decreases concern about undergoing a skin genital exam and may minimize resistance to full body skin examination in public skin cancer screenings.

Adult↗
PubMed1993

Common acquired melanocytic nevi, dysplastic melanocytic nevi and malignant melanomas: an image analysis cytometric study.

We used computerized image analysis cytometry to analyze 10 melanocytic lesions from each of the following categories: common acquired nevi, melanocytic nevi with architectural features of dysplasia, dysplastic melanocytic nevi (DMN) with slight atypia, DMN with moderate atypia, DMN with severe atypia, and superficial spreading melanomas. The nuclei of at least 50 consecutive nevomelanocytes in the most atypical zones were digitized at x 1000 under oil immersion, without knowledge of diagnosis by one observer. Grading of atypia was based on current practices as described in the literature. The results showed significant differences (p < 0.05) in nuclear area and standard deviation of nuclear area between melanoma and DMN with severe atypia, and between DMN with severe atypia and all other categories of nevi. There were no differences among any lesions with respect to nuclear shape. No differences in nuclear area were found among DMN with moderate, or slight atypia, nevi with features of dysplasia, and typical nevi. These results show for the first time objective distinction of low-grade (slight-moderate atypia), and high-grade or severe atypia in pre-malignant nevomelanocytic lesions of the skin.

Humans↗
PubMed1992

Sun exposure and sunscreen use following a community skin cancer screening.

BACKGROUND: In May 1988, a community skin cancer screening was held, and of the 251 individuals who attended, 214 (85%) completed a follow-up questionnaire. The objective of this study was to examine the associations among attitudes, knowledge, and behavior in those who had attended the screening. RESULTS: Analysis showed that females were twice as likely to have false positive screening diagnoses as males (odds ratio 2.2; P = 0.06). Attitudes toward tanning were not correlated with knowledge about the harmful effects of excess sun exposure (rp = -0.02; P = 0.67) or with behaviors such as reported sun exposure (for positive attitude versus "poor" attitude, linear trend P less than 0.11) and sunscreen use (linear trend P = 0.70). Behavior, defined as reported sunscreen use, was highly correlated with knowledge, both of the harmful effects of the sun and of the definition of SPF (linear trend P less than 0.001). Sunscreen use was also associated with the younger age group (those less than 59, P less than 0.05), female sex (P less than 0.001), higher education (P less than 0.05), and perceived risk for melanoma (P less than 0.05). CONCLUSIONS: We conclude that more targeted education in the domain of knowledge would benefit males and those over the age of 59.

Adult↗
PubMed1992

Histologic evaluation of pigmented lesions in Connecticut and its influence on the reporting of melanoma.

BACKGROUND: Underreporting of melanoma to state tumor registries has been identified as a problem in gathering accurate statistics on melanoma incidence. OBJECTIVE: Our purpose was to examine two factors that could influence the reporting of melanoma to the Connecticut Tumor Registry: histologic diagnosis of melanoma in the private offices of dermatologists and histologic diagnosis of melanoma in out-of-state laboratories. METHODS: From December 1990 to April 1991, questionnaires were sent to all known practicing dermatologists in the state of Connecticut (N = 149). Of the 127 dermatologists who were eligible, 124 (97.6%) completed the survey. RESULTS: The estimated number of melanomas diagnosed in private offices during 1990 was 9 to 18; this was based on the number of dermatologists who officially read their own slides (n = 19), the estimated number of melanomas diagnosed by these 19 dermatologists (n = 91), and the percentage of melanomas and uncertain pigmented lesion cases sent for consultation (80% to 90%). According to the estimates of Connecticut dermatologists, out-of-state laboratories diagnosed 84 of 523 melanomas (16%) in Connecticut residents. CONCLUSION: The diagnosis of melanoma in private offices did not appear to be a significant factor in underreporting whereas the diagnosis of melanoma in out-of-state laboratories did appear to be more significant. However, the possibility exists that some of these latter melanomas would eventually be reported at the time of reexcision.

Biopsy↗
PubMed1991

Sun protection in newborns. A comparison of educational methods.

We investigated the effect of education on the sun exposure of newborns. Mothers of healthy newborns (n = 275) were enrolled in the spring of 1989 and interviewed by telephone in the fall of 1989. The mothers were divided into a control group, a low-level intervention group, and a high-level intervention group. Both the low-level and high-level interventions succeeded in reducing the amount of time the newborns were allowed to spend in direct sunlight. Both types of intervention also resulted in reduced sun exposure time for the mothers. Although the number of mothers who used sunscreen was approximately the same in all three groups, when sunscreen use was controlled for, the intervention groups spent significantly less unprotected time in the sun than the control group. The mothers and newborns in both intervention groups simply spent less time outdoors.

Adolescent↗
PubMed1991

The histologic spectrum of pigmented spindle cell nevus: a review of 120 cases with emphasis on atypical variants.

The histopathologic features of 120 cases of pigmented spindled nevus (PSCN) from the years 1973 through 1988 were reviewed from a consultative practice heavily weighted with difficult nevomelanocytic lesions. The patients' mean age was 25.2 years, and females outnumbered males (68 versus 52). Extremity lesions made up 69.6% of the total, with the thigh the most common site. The lesions were categorized into one of four variants of PSCN, based on the presence or absence of various architectural and cytologic parameters and involvement of the reticular dermis. Thirteen cases (10.8%) were designated typical PSCN, and were characterized by fascicles of uniform pigmented spindle cells without cellular atypia and limited to the epidermis or papillary dermis. Ninety-five cases (79.2%) were classified as atypical PSCN (PSCN with architectural and/or cytologic atypia). Some of the latter also demonstrated substantial numbers of epithelioid cells, thus exhibiting some overlap with Spitz nevus. Eight cases showed striking features of dysplastic nevus. Ten cases had fascicles of pigmented spindle cells involving the reticular dermis ("plexiform" PSCN). Two cases were designated as combined PSCN because of the presence of banal nevus cells in addition to the spindle cell component. Clinical follow-up of a small group of patients has not suggested, to date, any aggressive behavior. Knowledge of PSCN and its atypical variants is important for discrimination from malignant melanoma.

Adolescent↗