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Timothy H McCalmont

Publications and source records attributed to Timothy H McCalmont.

13 recordsLinked to original sources
PubMed2005

Primary cicatricial alopecia: histopathologic findings do not distinguish clinical variants.

BACKGROUND: Primary cicatricial alopecias encompass a group of disorders characterized by permanent destruction of the hair follicle. The varied clinical features and differences in terminology have led to difficulties in defining consistent clinicopathologic correlation. OBJECTIVE: We sought clinicopathologic correlation of 6 clinically distinct primary cicatricial alopecias: lichen planopilaris, frontal fibrosing alopecia, pseudopelade (Brocq), central centrifugal alopecia, folliculitis decalvans, and tufted folliculitis. METHODS: We conducted prospective and blinded histopathologic evaluation of clinically typical primary cicatricial alopecias. Biopsy specimens were taken from early affected scalp lesions and paired with samples from clinically unaffected areas in the same patient. RESULTS: The lymphocytic and neutrophilic groups were readily distinguished histologically. However, within the two groups clinically distinct primary cicatricial alopecias could not be distinguished with current histopathologic techniques. CONCLUSION: A descriptive, standardized histopathologic reporting of follicular architecture, type, location, and extent of the inflammatory infiltrate, and presence or absence of sebaceous glands, may be of greatest value in guiding the treatment of patients with primary cicatricial alopecias.

Adult↗
PubMed2005

Genomic analysis of blue nevi and related dermal melanocytic proliferations.

Blue nevi are benign dermal melanocytic proliferations that can sometimes share overlapping microscopic features with melanoma. We used comparative genomic hybridization to analyze three groups of dermal melanocytic proliferations. Group 1 consisted of 10 cellular blue nevi and 1 deep penetrating nevus, none of which showed chromosomal aberrations. Group 2 consisted of 11 lesions that were histopathologically ambiguous. Three of these lesions demonstrated chromosomal aberrations (three or fewer per lesion). Group 3 consisted of seven histopathologically malignant lesions, each showing three or more chromosomal aberrations. Moderate to severe cytologic atypia and a mitotic rate of three or more mitoses per 10 high power fields were present in six of eight (75%) lesions that had at least three chromosomal aberrations but were absent in 15 of 20 (75%) lesions without chromosomal aberrations. Necrosis was present in four of the 29 (13%) lesions, with every lesion with necrosis demonstrating three or more genomic abnormalities. In conclusion, histopathologically unequivocally benign or malignant dermal melanocytic proliferations show nonoverlapping patterns of chromosomal aberrations. Ambiguous lesions can be separated into lesions with and without chromosomal aberrations. Future studies with clinical follow-up are necessary to determine which aberrations are most informative for classification of these lesions.

Adolescent↗
PubMed2004

Perineural spread of malignant melanoma of the head and neck: clinical and imaging features.

BACKGROUND AND PURPOSE: Extension of malignant melanoma along cranial nerves is a little-known complication of malignant melanoma of the head and neck. We describe the clinical and MR imaging findings of perineural spread of malignant melanoma to cranial nerves, emphasizing that this entity occurs more commonly with desmoplastic histology and may have a long latent period following primary diagnosis. METHODS: At two institutions, we identified and retrospectively reviewed eight cases of malignant melanoma of the head and neck that had MR imaging evidence of perineural spread of disease. All patients underwent confirmatory tissue sampling. RESULTS: Seven patients had melanomas of the facial skin or lip, and one patient had a primary sinonasal lesion. By histopathology, these melanomas included five desmoplastic, two mucosal, and one poorly differentiated melanotic spindle-cell tumor. All patients developed symptomatic cranial neuropathy an average of 4.9 years from the time of initial diagnosis. MR imaging demonstrated postgadolinium enhancement of at least one branch of the trigeminal nerve in all cases and of at least one other cranial nerve in five cases. Other findings included abnormal contrast enhancement and soft tissue thickening in the cavernous sinus, Meckel's cave, and/or the cisternal segment of the trigeminal nerve. CONCLUSION: Although perineural spread of disease occurs most commonly with squamous cell carcinoma and adenoid cystic carcinoma, malignant melanoma must also be included in this differential diagnosis, particularly if the patient's pathology is known to be desmoplastic. Similarly, any patient with malignant melanoma of the head and neck who undergoes MR imaging should receive an imaging assessment focused on the likely routes of perineural spread.

Adult↗
PubMed2003

Systemic and cell type-specific gene expression patterns in scleroderma skin.

We used DNA microarrays representing >12,000 human genes to characterize gene expression patterns in skin biopsies from individuals with a diagnosis of systemic sclerosis with diffuse scleroderma. We found consistent differences in the patterns of gene expression between skin biopsies from individuals with scleroderma and those from normal, unaffected individuals. The biopsies from affected individuals showed nearly indistinguishable patterns of gene expression in clinically affected and clinically unaffected tissue, even though these were clearly distinguishable from the patterns found in similar tissue from unaffected individuals. Genes characteristically expressed in endothelial cells, B lymphocytes, and fibroblasts showed differential expression between scleroderma and normal biopsies. Analysis of lymphocyte populations in scleroderma skin biopsies by immunohistochemistry suggest the B lymphocyte signature observed on our arrays is from CD20+ B cells. These results provide evidence that scleroderma has systemic manifestations that affect multiple cell types and suggests genes that could be used as potential markers for the disease.

Adult↗
PubMed2003

Lymphomatoid papulosis associated with mycosis fungoides: a study of 21 patients including analyses for clonality.

BACKGROUND: Although an association of lymphomatoid papulosis (LyP) with mycosis fungoides (MF) is recognized, our understanding of this relation is limited. OBJECTIVE: We sought to document the clinical experience at the University of California, San Francisco, in 21 patients who had both LyP and MF and to do clonality studies in 7 of those patients in whom this was possible. METHODS: We conducted chart review of the 21 patients and analysis for T-cell receptor-gamma gene rearrangements by the polymerase chain reaction. RESULTS: Of 54 patients, 21 (39%) with LyP had associated MF. LyP preceded MF in 14 (67%), MF preceded LyP in 4 (19%), and there was concurrent appearance in 3 (14%). Of the 21 patients, 20 (95%) were type A and only 1 (5%) was type B. An identical clone was found in lesions of both LyP and MF in all 7 patients in whom analysis was possible. CONCLUSION: Findings of this study strengthen the idea that LyP and MF are related T-cell lymphoproliferative disorders.

Adolescent↗
PubMed2002

Mycosis fungoides: the great imitator.

A considerable number of reports have documented mycosis fungoides (MF) mimicking other dermatoses, but a comprehensive review has not been published. Our aim was to comprehensively review reports of various dermatoses simulated by MF. Additionally, 2 cases in which MF simulated diseases not previously documented (psoriasis and erythema annulare centrifugum) are presented. A literature search of all case reports of MF cited in the MEDLINE database from 1966 through 2000 plus those in one of the author's (H. Z.) files was performed. A total of 23 reported cases of dermatoses mimicked by MF were found. With the additional 2 dermatoses now presented, this yields a total of at least 25 diseases that can be simulated by MF. In view of the considerable number of dermatoses simulated by MF, the term the great imitator is appropriate for MF.

Adult↗
PubMed2002

Cutaneous manifestations of hyper-IgE syndrome in infants and children.

We describe 8 children with hyper-IgE syndrome who had papulopustular eruption on the face and scalp in the first year of life. Seven of the 8 patients had persistent peripheral eosinophilia and 3 had leukocytosis noted before diagnosis. Skin biopsy specimens in 6 patients revealed spongiosis and perivascular dermatitis and/or folliculitis with a predominance of eosinophils. Two patients had bone fractures and osteopenia. Recurrent pneumonia occurred in 6 children and pneumatoceles in 5. The diagnosis of hyper-IgE syndrome was made an average of 18 months after the onset of the initial papulopustular eruption. These findings may lead to earlier recognition of the disease and institution of appropriate treatment.

Anti-Bacterial Agents↗
PubMed2002

Hypopigmented mycosis fungoides: frequent expression of a CD8+ T-cell phenotype.

Hypopigmented mycosis fungoides (MF) is a form of cutaneous T-cell lymphoma in which hypopigmentation occurs in the absence of classic lesions of MF. Hypopigmented MF predominantly affects people with dark complexions. The natural history of this variant of cutaneous T-cell lymphoma is similar to that of conventional MF, although the disease onset is usually in childhood or adolescence. In a retrospective study we evaluated the clinical, histopathologic, immunohistochemical, and molecular characteristics of hypopigmented MF in 15 patients. Similar to other reports, the disease onset occurred in childhood and adolescence in most of the cases. The survival rate was comparable with that of classic MF. We did not observe progression to systemic disease or lymph node involvement. Histopathologically hypopigmented lesions were indistinguishable from hyperpigmented or erythematous patches. On immunohistochemical analysis a predominantly CD8+ infiltrate was detected in the majority of cases (nine of 15 patients). To determine whether epidermotropic CD8+ T cells represent the malignant T-cell clone or whether these cells are innocent, tumor-infiltrating T lymphocytes, we performed microdissection of epidermotropic CD8+ T cells and analyzed T-cell receptor-gamma chain gene for rearrangements. The epidermotropic CD8+ T lymphocytes showed clonal T-cell receptor gene rearrangement and therefore represented the malignant T-cell clone. We conclude that hypopigmented MF tends to occur in young people and that it belongs to the group of CD8+ cutaneous T-cell lymphomas in the majority of cases.

Adolescent↗