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M C Mihm

Publications and source records attributed to M C Mihm.

At least 145 records · Page 8Linked to original sources
PubMed1989

Nonfamilial cutaneous melanoma incidence in women associated with sun exposure before 20 years of age.

Despite strong evidence that sun exposure causes malignant melanoma, the details of this relation remain unclear. A nested case-control analysis was conducted within the Nurses' Health Study cohort to examine the relation between timing of severe sun exposure and incidence of melanoma. The subjects were 130 white women aged 38 to 65 years with confirmed cutaneous melanoma (other than acral lentigenous) who reported no history of melanoma in first-degree relatives. The control subjects were 300 women matched by race, date of birth, and cycle of questionnaire who also reported no history of melanoma in first-degree relatives. We used conditional logistic regression to evaluate the relation of sun damage after 30 years of age and sun damage from 15 to 20 years of age to the incidence of melanoma. Blistering sunburns between 15 to 20 years of age were associated with risk of melanoma (relative risk = 2.2 for five or more burns vs none, 95% confidence interval 1.2 to 3.8). This association persisted when a history of burns after 30 years of age was controlled in the analysis. No material association was found between blistering sunburns after 30 years of age and melanoma. Similarly, a more equatorial latitude of residence between 15 and 20 years of age was positively associated with melanoma; latitude after 30 years of age was less strongly and not significantly related to melanoma risk. Sun exposure prior to 20 years of age is more closely associated with melanoma risk than sun exposure after 30 years of age.

Adolescent↗
PubMed1989

Dysplastic melanocytic nevi: a reproducible histologic definition emphasizing cellular morphology.

Histologic criteria commonly used to diagnose dysplastic melanocytic nevi (DMN) have not been correlated adequately with biology nor subjected to rigorous reproducibility studies. To address these failings, we developed histologic definitions emphasizing cellular morphology based on the appearance of typical melanocytes in sun-protected buttock skin, fully-evolved atypia in the vertical component of metastasizing primary cutaneous melanomas, and slight and moderate degrees of atypia defined within these limits in selected varieties of DMN. Reproducibility of our histologic definitions were tested by using two pathologists working independently to assess single routine tissue sections of 19 melanocytic lesions on two occasions at least 6 mo apart. Lesions included five previously diagnosed primary invasive cutaneous melanomas, seven lesions selected for gross morphologic features characteristic of DMN, and four solar lentigines and three common acquired nevomelanocytic nevi preselected for typical appearance and stable growth history. For the primary pathologist using the grading scheme, agreement rates between first and second readings were 84% for final diagnosis and 79% for the highest degree of cellular atypia; for the secondary pathologist, agreement rates for first and second readings for both parameters were 84%. Agreement rates comparing second readings of final diagnosis and highest degree of cellular atypia by the two pathologists were 89% and 79%, respectively. Most of the architectural and host response features commonly associated with DMN were less reproducible. In conclusion, we demonstrated very good reproducibility of histologic definitions used to differentiate the intraepidermal component of DMN from that of melanoma and benign melanocytic and nevomelanocytic hyperplasias, based on a biologic correlation emphasizing cellular morphology. Reproducible histologic definitions are a requisite first step in defining a clinical-pathologic correlation for DMN.

Adolescent↗
PubMed1988

Self-reports of mole counts and cutaneous malignant melanoma in women: methodological issues and risk of disease.

The relation of the presence of moles (nevi) on all four limbs to risk of cutaneous malignant melanoma was explored among 98 incident cases aged 32-59 years at diagnosis and 190 age-matched controls drawn from the Nurses' Health Study, a prospective cohort of female nurses in the United States. Cases diagnosed during follow-up from 1976 to 1982 were included in this study. Participants reported counts of all moles and raised moles alone on postal questionnaires. Distributions of moles were similar for right and left sides on upper and lower limbs for cases and controls. Counts declined with increasing age for all women, from a median of 15 for the youngest tertile of controls (aged 36-46 years) to three for the oldest (aged 54-62 years). Cases had more moles than did controls (medians of 23 and 9, respectively, for total moles on all four limbs): The presence of any mole on a limb gave relative risks for melanoma ranging from 2.2 (95% confidence interval (CI) = 1.2-4.0) for one or more moles on an arm to 2.9 (95% CI = 1.6-5.3) for one or more moles on the lower limb. For raised moles, relative risks were 1.7 (95% CI = 1.0-2.7) for arm, 2.1 (95% CI = 1.3-3.5) for lower limb, and 3.5 (95% CI = 2.0-6.3) for leg (below knee). The highest site-specific risk (i.e., for any moles on the same limb as the melanoma vs. no moles on that limb) was for moles on the lower limb (relative risk = 5.0 (95% CI = 1.8-13.5)). There were positive and significant trends in overall and site-specific risk with increasing numbers of moles on all limbs when absolute mole counts were considered, e.g., for total moles on all four limbs combined, chi for trend = 4.0, one-sided p less than 0.001, with relative risk for more than 100 moles versus none of 6.0. Inclusion of sun exposure and other constitutional factors in logistic regression analyses did not alter these observed relations between the presence of moles and risk of melanoma.

Adult↗
PubMed1988

Histologic reporting of malignant melanoma.

The schema for histologic reporting of malignant melanoma outlined above is incomplete. A number of variables, including quantification of tumor cell pigmentation, description of solar degeneration in surrounding stroma, and extent of S-100 protein immunoreactivity by tumor cells, have not been addressed. In addition, it is likely that within the next several years, additional parameters, including those identified by the use of in situ genomic probes (Chapter 3), will become known to confer prognostic information when assessed histologically in biopsy material. Nonetheless, this approach represents a start, an attempt to achieve uniformity in histologic reporting of melanoma. It represents a three-tiered approach. First is the establishment of a malignant melanocytic lesion (malignant melanoma) and the assessment of the anatomic level and extent of invasion of the dermis, which correlates directly with metastatic potential (the vertical growth phase measured in millimeters). Subclassification of the radial growth phase is optional and, by convention, is also reported in this "above the line" portion of the diagnostic assessment. Second, a number of subsidiary diagnostic statements, usually in the form of notes or comments, are recommended. These include assessment of overlying epidermal ulceration, a description of the morphology and mitotic activity of the vertical growth phase nodule, an assessment of the presence or absence of vascular invasion and microscopic satellite formation, a description of the host mononuclear cell response and/or regression, and mention of associated pathology. Finally, an additional narrative statement may be included to describe such things as extent of S-100 immunoreactivity or to modify in a more descriptive manner the database provided above. Although this last category is neither crucial nor mandatory, it serves to add to a collective database from which future determinations concerning the prognostic significance of new histologic parameters may be formulated. Table 6.3 provides a sample report based on the above considerations. This method of histologic reporting is recommended because it includes important diagnostic information as well as parameters for prognosis. Although certain details of less impelling current significance are included, these are of potential future importance as a greater number of patients with malignant melanoma are followed prospectively for prolonged periods of time. These factors may also prove to be significant in the accumulation of a database for research.

Epidermis↗
PubMed1987

Risk factors for cutaneous melanoma. A practical method of recognizing predisposed individuals.

Cutaneous melanoma is rapidly becoming a potentially curable cancer if it is detected and properly treated in an early phase of development. Unlike other cancers, which are usually hidden from detection until they are relatively large or metastatic disease has occurred, cutaneous melanoma is readily detectable simply by examining the skin. Information is now available that will be useful in selecting individuals at greatest risk. The most important melanoma risk factors (in decreasing order of importance) for a given individual are as follows: a persistently changed or changing mole, adulthood, irregular varieties of pigmented lesions (including dysplastic moles and lentigo maligna), a congenital mole, Caucasian race, a previous cutaneous melanoma, a family history of cutaneous melanoma, immunosuppression, sun sensitivity, and excessive sun exposure. Selective screening and appropriate treatment of individuals who have these risk factors may reduce the morbidity and mortality of cutaneous melanoma.

Adult↗
PubMed1987

Recanalization of occluded biliary endoprostheses with pulsed laser radiation.

The use of pulsed laser radiation to recanalize occluded biliary endoprostheses was examined. In vitro measurements demonstrated that a repetitively pulsed organic dye laser transmitted through a small diameter quartz fiber can recanalize an occluded stent in less than 10 sec without causing visible damage to the stent. The laser parameters required for recanalization do not result in significant damage to the common bile duct of a pig even when the laser energy is delivered directly into the tissue, indicating that biliary endoprostheses can be cleared with a large margin of safety. Although the duration of this effect is unknown, pulsed laser radiation is a simple, safe, and effective means of recanalizing occluded biliary endoprostheses and may be an alternative to stent replacement.

Animals↗
PubMed1987

Malignant melanoma with desmoplasia and neurotropism.

Desmoplastic (DMM) and neurotropic (NMM) malignant melanoma are two variants of the vertical growth phase of malignant melanoma. Both lesions commonly present clinically as firm nodules that are often mistaken for fibromas. Histologically, they are associated with a pleomorphic spindle cell population of cells that widely infiltrate the dermis. An accompanying fibrosis is present. DMM usually lies beneath a lentiginous proliferation of a typical melanocytes, whereas NMM may arise without obvious epidermal involvement. Because the lesions infiltrate widely, adequate therapy results only when complete extirpation is performed. Otherwise, there may be recurrence. Recurrent lesions act more aggressively.

Cell Transformation, Neoplastic↗
PubMed1987

Kimura's disease and angiolymphoid hyperplasia with eosinophilia: two distinct histopathological entities.

The relationship between the disorder known in Japanese and Chinese literature as Kimura's disease and that known in Western literature as angiolymphoid hyperplasia with eosinophilia (ALHE) has been the subject of debate. Many reports have used the terms synonymously. We have reviewed the histological and clinical features of 4 cases, all occurring in Caucasians, 2 of which are typical of Kimura's disease and 2 of ALHE. Analysis of the cases indicates that the histological features of the 2 disorders are sufficiently different to warrant their recognition as 2 distinct entities. The histological and clinical features of Kimura's disease are most consistent with an allergic or autoimmune process in which blood vessels, lymphocytes and eosinophils participate. Those of ALHE suggest a primary, probably neoplastic disorder of vascular endothelium with a variable and secondary inflammatory response. Although there is some clinical overlap between patients with the 2 disorders, the histological features are distinctive, and the 2 terms should not be used synonymously.

Adult↗
PubMed1986

Prognosis for polypoidal melanoma is determined by primary tumor thickness.

Survival of 23 patients with polypoidal malignant melanomas was compared with an identical number of patients with nonpolypoidal melanomas of similar thickness, stage, and location. Five-year survivals for the two groups were not significantly different. The dominant prognostic factor leading to the adverse prognosis associated with polypoidal melanomas was the primary tumor thickness (all greater than 1.70 mm) and not the polypoidal morphologic configuration per se.

Adolescent↗
PubMed1986

The spectrum of minimal deviation melanoma: a clinicopathologic study of 21 cases.

A retrospective study of 21 patients with the histopathologic diagnosis of minimal deviation melanoma (MDM; n = 18) and borderline melanoma (BM; n = 3) was undertaken to determine the prognosis for these patients compared with that for patients with other types of malignant melanoma. The findings indicate that the prognosis for these uncommon nevomelanocytic tumors is somewhat better than that for other malignant melanomas. Follow-up periods in this series ranged from 18 to 96 months (mean, 57 months). Primary lesions ranged in thickness from 1.6 to 10.4 mm. The histopathologic subtypes included the Spitz variant (nine patients), the spindle cell variant (six patients), the combined spindle and epithelioid cell type (three patients), and the small epithelioid cell type (three patients). Only two of the patients died of widespread metastatic disease. Comparison of the histologic and clinical prognostic indicators of mortality in patients who have malignant melanoma with the clinical and pathologic features seen in this series of 21 patients would appear to indicate a diminished tendency toward metastatic or recurrent disease in patients with MDM and BM.

Adolescent↗
PubMed1986

Erythema nodosum leprosum: nature and extent of the cutaneous microvascular alterations.

Skin biopsy specimens from four patients with erythema nodosum leprosum, when examined as Epon-embedded, 1-micron sections, exhibited a necrotizing vasculitis involving capillaries, venules, and small-to-medium arteries and veins. In the superficial dermis, affected venules and capillaries showed endothelial cell enlargement and focal necrosis associated with perivascular infiltrates of lymphocytes. In the deep dermis and subcutaneous tissue, affected venules, arterioles, and arteries exhibited endothelial cell necrosis and matted fibrin in the vessel walls associated with perivascular infiltrates of neutrophils. Throughout the dermis, mononuclear phagocytes with vacuoles containing numerous fragmented organisms were observed. By electron microscopy, electron-dense material resembling immune complexes was observed in the walls of these vessels. These observations support the concept that erythema nodosum leprosum is an immune complex-mediated necrotizing vasculitis involving capillaries, arterioles, arteries, venules, and veins.

Adult↗
PubMed1986

Erythema multiforme in a patient with T cell chronic lymphocytic leukemia.

A patient with T4+ (helper-inducer) T cell chronic lymphocytic leukemia developed an erythema multiforme-like eruption, the diagnosis of which was supported by routine light microscopic findings. Immunopathologic studies using monoclonal antibodies demonstrate that despite an overwhelming majority of leukemic T4+ cells in the peripheral blood and dermal infiltrate, the predominant cells in the epidermal infiltrate are T8+ (cytotoxic-suppressor) cells. These findings are different from those seen in epidermotropic T cell leukemic infiltrates and are similar to those previously reported in erythema multiforme. Thus it is likely that the leukemic T4+ cells are participating in this cutaneous hypersensitivity reaction along with residual, normal T8+ cells.

Aged↗