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Research
Abstracts
Pilary
Complex Carcinoma: An Adnexal Carcinoma of the Skin with Differentiation
towards the Components of the Pilary Complex
Homayoon Rahbari, M.D. and Amir H. Mehregan, M.D.
We report twelve cases with a distinctive form of adnexal carcinoma
occurring most commonly over the head and neck of relatively old
individuals. The growth was single in all cases, deep dermal in location,
and consisted of massive proliferation of small basaloid cells with only
occasional connection with the surface epidermis. The basaloid tumor masses
showed only a few areas of palisading of their outer cell nuclei and
occasional retraction space formation. The neoplasm revealed scattered areas
of trichilemmal and epidermoid keratinization, foci of sebaceous, and areas
of sweat ductal differentiation indicating participation of various
components of the pilary complex.
Key Words: adnexal carcinoma-pilary complex; atypical basal cell epithelioma;
adnexal differentiation; trichilemmal keratinization
JDA 1993;20:630-7
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Phakomatosis Pigmentovascularis: Report of a Case
M. Mahroughan, M.D., Amir H. Mehregan, M.D., and David A. Mehregan, M.D.
Pinkus Dermatopathology Laboratory, Monroe, Michigan
Phakomatosis pigmentovascularis is a rare cutaneous malformation
characterized by a combination of melanocytic nevi and nevus flammeus. We
report a 16-year-old boy with extensive and predominantly unilateral skin
involvement combining features of speckled melanocytic nevi over a
background of nevus flammeus. A brief review of the literature and
classification of this phakomatosis is presented.
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Epidermotropic Metastatic Malignant Melanoma
David A. Mehregan, MD, Monroe, Michigan
Michael T. Bergeon, MD, Saginaw, Michigan
Darius R. Mehregan, MD, Monroe, Michigan
Epidermotropic metastatic malignant melanoma can simulate a primary
malignant melanoma. However, since therapeutic management can be drastically
different for these two lesions, care must be taken in evaluating them. We
report a woman with forty-eight metastatic lesions of maligant melanoma,
twenty-two of which were removed and found on histologic examination to be
epidermotropic metastatic malignant melanoma.
CUTIS 1995; 55; 225-7
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Giant Cerebriform and Disseminated Molluscum
Contagiosum in Atopic Dermatitis
Melanie K. Kuechle, MD, Darius R. Mehregan, MD, Randall K. Roenigk, MD,
and Sigfrid A. Muller, MD
Patients with atopic dermatitis have an increased susceptibility to certain
viral infections, particularly those caused by Herpes simplex virus, human
papilloma virus, and molluscum contagiosum. We describe two patients with
atopic dermatitis who had unusually widespread and large lesions of
molluscum contagiosum. One patient had a clonal proliferation of a T-cell
population with an aberrant phenotype, and the other had persistent
eosinophilia with marked elevation of IgE. The unusual clinical
presentations of molluscum contagiosum and its association with altered
immunity and atopic dermatitis are discussed.
Key words: atopic dermatitis, clonal T-cells, eosinophilia, increased IgE,
molluscum contagiosum.
Eur J Dermatol 1996; 6: 274-7
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Axillary Granular Parakeratosis
David A. Mehregan, MD, Paul Vandersteen, MD, Lynn Sikorski, DO,
and Darius R. Mehregan, MD, Monroe, Michigan
We report two cases of axillary granular parakeratosis which is a unique
eruption involving the axilla that has distinctive histopathologic features.
Both of our patients had slightly pruritic, hyperpigmented patches in the
axilla. The biopsy specimens revealed severe compact parakeratosis with
maintenance of the stratum granulosum and retention of keratohyalin granules
throughout the stratum corneum which was markedly thickened and measured
between 90 to 185 um. The exact etiology is not known, but this condition is
believed to represent a contact reaction to an antiperspirant or deodorant.
JAAD 1995; 33; 373-5
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Spindle Cell Lipomas: A Report of Two Cases, One
with Multiple Lesions
Darius R. Mehregan, MD, David A. Mehregan, MD, Amir H. Mehregan, MD,
Michael A Dorman, MD, and Edwin Cohen, MD
BACKGROUND: Spindle cell lipoma is an unusual and histologically distinctive
form of lipoma occurring primarily in older individuals.
OBJECTIVE: The dermatologic surgeon and pathologist should be familiar with
this variant of lipoma.
METHODS: We are reporting two cases of spindle cell lipomas with the results
of histologic examination with special stains and immunohistochemical
studies.
RESULTS: The neoplasms consisted of lobulated masses of mature adipose
tissue with areas of spindle cell proliferation. There was strong positive
staining with antibodies for vimentin within the areas of spindle cell
proliferation. One of the cases is unusual in that multiple lesions are
occurring in a young patient.
CONCLUSION: Recognition of the histologic pattern is important in
distinguishing the benign spindle cell lipoma from the malignant liposarcoma.
Dermatol Surg 1995; 21: 796-8
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Chronic Lupiod Leishmaniasis: Evaluation by Polymerase Chain Reaction
Ali Z. Momeni, MD, Shinichi Yotsumoto, MD, Darius R. Mehregan, MD, Amir H.
Mehregan, MD,
David A. Mehregan, MD, Mali Aminjavaheri, MD, Hiroshi Fujiwara, MD, and Joji
Tada, MD
BACKGROUND: The cutaneous lesions in chronic lupoid leishmaniasis resemble
those of lupus vulgaris, both clinically and histologically. The
differential diagnosis is difficult and may depend on the detection of a few
Leishmania amastigotes in the histologic sections, the growth of the
promastigotes in cultures, or the identification of amastigotes by other
techniques. Polymerase chain reaction was used to detect Leishmania
amastigote DNA in tissue samples obtained from 65 patients with chronic
lupoid leishmaniasis, and the results were confirmed by Southern blot
analysis.
Observations: The histologic findings of a predominantly epithelioid cell
granuloma surrounded by lymphocytic infiltrate in chronic lupoid
leishmaniasis are very similar to those observed in lupus vulgaris.
Extensive histologic examination of the sections in this series revealed
occasional macrophages containing a few amastigotes in only 12 cases.
Cultures in NNN medium yielded Leishmania promastigotes in 20 cases.
Polymerase chain reaction studies using a Leishmania-specific primer
identified Leishmania DNA in 30 of 63 cases, and those using a Mycobacterium
tuberculosis primer were found to be negative for mycobacteria in 47 cases
tested, including 11 cases with a positive tuberculin skin reaction.
Conclusions: The histologic findings in chronic lupoid leishmaniasis
resemble those of lupus vulgaris. Polymerase chain reaction studies were
useful in identifying amastigotes in 30 (47.6%) of 63 cases. This study
confirms the presence of DNA molecules of Leishmania amastigotes in samples
of formalin-fixed, paraffin-embedded granulomatous tissue obtained from
patients with chronic lupoid leishmaniasis.
Arch Dermatol 1996;132:198-202
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Sebaceous Epithelioma: A Review of Twenty-one Cases
Annette M. Dinneen, MBBCh, and Darius Mehregan, MD, Rochester, Minnesota
Background: Sebaceous epithelioma is a benign tumor that must be
differentiated from basal cell carcinoma and other appendageal tumors.
Objective: Histologic and clinical findings were reviewed in 21 patients
with sebaceous epitheliomas.
Methods: Twenty-one cases of sebaceous epithelioma collected during a 5-year
period were reviewed.
Results: The tumors appeared as yellow to flesh-colored papules, most often
on the face and neck. They consisted of basaloid cells with foci of
sebaceous differentiation. Cystic spaces formed by holocrine degeneration or
simulating sebaceous duct lining were common findings. Patients with
sebaceous epitheliomas were more likely than the general population to have
an internal malignancy.
Conclusions: Patients with sebaceous epithelioma should be examined for an
underlying malignancy.
JAAD 1996;334:47-50
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Amelanotic Lentigo Maligna Melanoma A Diagnostic
Conundrum; Presentation of Four New Cases
Homayoon Rahbari, M.D., Hossein Nabai, M.D., Amir H. Mehregan, M.D.,
David A. Mehregan, M.D., Darius R. Merhregan, M.D., and Judith Lipinski, M.D.
Background: The clinical appearance of amelanotic lentigo maligna melanoma (ALMM)
is quite confusing and usually is not diagnosed prior to histopathologic
examination.
Methods: We have studied four new patients with ALMM whose correct diagnosis
was not obtained from any one clinical finding. We arrived at the final
diagnosis in an unexpected way, having had biopsied the lesions for
diagnoses other than malignant melanoma.
Results: ALMM presents as a nonspecific skin lesion with no single
indicative characteristic. A search of the literature confirmed our
difficulty in making the diagnosis.
Conclusions: To diagnose ALMM, one has to be cognizant of this condition and
has to consider a constellation of findings that are unusual with
melanocytic lesions. Questionable lesions must be biopsied for definitive
histopathologic diagnosis.
KEYWORDS: amelanotic melanoma, lentigo maligna, dermatitic lesions, scaly
elevated pruritus.
Cancer 1996; 77:2052-7
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Proliferating Cell Nuclear Antigen Staining in
Deep-Penetrating Nevi
Darius R. Mehregan, MD, David A. Mehregan, MD and Amir H. Mehregan, MD,
Monroe, Michigan
Abstract
Deep-penetrating nevus is a term proposed by Seab et al. to describe a
distinctive benign melanocytic growth. The histologic differential diagnosis
includes Spitz nevus, blue nevus, combined blue nevus and acquired
melanocytic nevus, and malignant melanoma.
Clinically, the lesions often appear darkly pigmented. Clinicians may
suspect either a blue nevus or a malignant melanoma and are often concerned
about the extension of pigment into the subcutaneous fat at the time of
excision.
Proliferating cell nuclear antigen (PCNA, cyclin) is a 36 kd marker of
cellular proliferation that represents an accessory protein of DNA
Delta-polymerase. The expression of PCNA is increased during the late G
growth phase and peaks in the S phase of the cellular cycle. Recent studies
have suggested that such markers of cellular proliferation may be useful in
differentiating benign from malignant neoplasms or as prognostic markers in
malignant neoplasms. Staining for PCNA has been reported in studies of
squamous cell carcinoma, basal cell carcinoma, keratoacanthoma, and
malignant melanoma. We have reviewed histologic sections of deep-penetrating
nevi for the presence of PCNA and our results are reported.
JAAD 1995;33:685-7
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Cutaneous Malakoplakia: A Report of Two Cases with
the use of Anti-BCG for the Detection for Micro-Organisms
Darius R. Mehregan, M.D., Amir H. Mehregan, M.D., and David A. Mehregan,
M.D.,
Monroe, Michigan
Malakoplakia is an uncommon granulomatous infectious disease that is found
primarily in the genito-urinary tract, but may rarely involve the skin.
Histologic findings are marked by the presence of foamy macrophages
containing basophilic concentric spherules, the Michaelis-Gutman bodies.
Micro-organisms are not readily identifiable. Immunostaining with polyclonal
anti-mycobacterium bovis (BCG) has been described as a method of identifying
bacterial and fungal organisms in situations where organisms may be sparse.
We report two cases of cutaneous malakoplakia with demonstration of
organisms by immunostaining with anti-BCG antibodies.
JAAD; 43:351-4
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Staining of Melanocytic Neoplasms by Melanoma
Antigen Recognized by T Cells
Darius R. Mehregan, M.D., Amir H. Mehregan, M.D., and David A. Mehregan,
M.D.,
Monroe, Michigan
We stained benign melanocytic nevi and malignant melanoma with antibodies to
melanoma antigen recognized by T cells (Mart-1) to determine if this was
useful in differentiating benign from malignant melanocytic neoplasms.
Forty-five primary malignant melanomas and 71 benign melanocytic nevi were
stained with antibodies to Mart-1. Two cases of malignant melanoma
metastatic to lymph node and three cutaneous metastases of malignant
melanoma were also stained. The degree of staining was graded into diffuse
positive staining, focal positive staining, and negative staining.
Thirty-six of 45 primary malignant melanomas stained diffusely positive with
antibodies to Mart-1. This included three of five desmoplastic malignant
melanomas that showed positive staining. Four melanomas showed faint or
focal positive staining. One of two metastases to lymph node showed strong
positive staining and one showed no staining. All three cutaneous metastases
showed diffuse positive staining. Sixty-one of 71 melanocytic nevi showed no
staining or faint staining with antibodies to Mart-1. Ten of 71 melanocytic
nevi showed strong positive staining. The majority of these were congenital
nevi. Staining with antibodies to Mart-1 antigen was a useful marker of
malignant melanoma. However, staining may also be seen in benign melanocytic
neoplasms. The presence or absence of staining for Mart-1 antigen cannot be
used to differentiate benign melanocytic nevi from malignant melanocytic
tumors.
Key Words: Immunohistochemistry; Mart-1; Melanoma; Melanoma antigen related
to T cells; Nevus; Pathology; Spitz Nevus
Am J Dermatopathol 2000; 22: 247-250
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