Search PubMed⌕ Search

Biomedical subjects

M G Hitchcock

Publications and source records attributed to M G Hitchcock.

At least 19 recordsLinked to original sources

Utility of rush paraffin-embedded tangential sections in the management of cutaneous neoplasms.

BACKGROUND: Mohs micrographic surgery (MMS) modified by the use of tangential, formalin-fixed, paraffin-embedded histologic specimens is advantageous in treating selected skin neoplasms. OBJECTIVE: To review the use of our experience with a modification of MMS to treat lentigo maligna melanoma (LMM), lentigo maligna (LM) and other melanoma in situ (MIS) lesions, dermatofibrosarcoma protuberans (DFSP), atypical fibroxanthoma (AFX), and angiosarcoma. METHODS: Our experience utilizing a modification of MMS in the treatment of 77 patients with LM or other MIS, 23 patients with LMM, 11 patients with DFSP, 1 patient with AFX, and 1 patient with angiosarcoma was reviewed. Length of follow-up and rate of recurrence were examined. A literature review of this pertinent modification of the Mohs technique was performed. RESULTS: One hundred fourteen patients underwent MMS for melanocytic (LM, MIS, LMM), spindle cell (DFSP, AFX), and vascular malignant neoplasms. One patient developed locally recurrent LM and one patient with LMM developed satellite metastasis. Regional lymph node metastasis occurred in one patient with LMM and in a patient with angiosarcoma. CONCLUSION: The use of Mohs micrographic surgery in conjunction with rush formalin-fixed, paraffin-embedded tangential histologic sections provides the accuracy and tissue conservation of the Mohs procedure while ensuring more confident interpretation of histology in cases of lentigo maligna, lentigo maligna melanoma, dermatofibrosarcoma protuberans, atypical fibroxanthoma, and angiosarcoma.

Aged↗

Diagnosis: erythema nodosum or not?

Erythema nodosum is the final common pathway to a myriad of insults and is thought to be a hypersensitivity reaction centered in the subcutis. To recognize the histological spectrum of erythema nodosum, one must be aware of the morphologic chronology of the disease (early, fully developed, late) and its clinical variants (erythema nodosum migrans). This article reviews the range of changes that can be seen in this prototype of a septal panniculitis and describes the diversity that may be accepted in the diagnosis. Differential diagnoses at each stage of disease development are discussed. The criteria elaborated should assist the pathologist in answering the clinician's query, "Erythema nodosum, or not?"

Diagnosis, Differential↗

Apocrine poroma: a distinctive case in a patient with nevoid basal cell carcinoma syndrome.

Traditionally, poromas have been classified as eccrine neoplasms, but several recent reports of poroid tumors with sebaceous, follicular, and apocrine differentiation have challenged this idea. In support of alternative differentiation, a case of an "apocrine" poroma is reported in a 19-year-old man with the nevoid basal cell carcinoma syndrome. A papule on the right cheek, thought clinically to be a basal cell carcinoma, was excised. Anastomosing lobules of small uniform basaloid (poroid) cells formed small ductular structures lined by eosinophilic cuticles and extended into the superficial reticular dermis. The neoplasm originated from follicular infundibula and was surrounded by a myxoid stroma. Focally, primitive hair bulb and papillae differentiation was present, and some of the ducts were lined by cells suggesting decapitation secretion. The histologic pattern and the common embryologic origin of the folliculosebaceous-apocrine unit support apocrine differentiation of this tumor. The association with the nevoid basal carcinoma syndrome appears to be unique. This case, in addition, demonstrates overlapping features with the infundibulocystic type of basal cell carcinoma commonly seen in the basal cell nevus syndrome.

Adult↗

Cutaneous melanoma with myxoid features: twelve cases with differential diagnosis.

Substantial myxoid change can occur in malignant melanoma, but its importance in primary disease has not been systematically evaluated. This report describes the clinical, microscopic, histochemical, and immunohistochemical findings in 12 patients with primary cutaneous malignant melanoma with myxoid features. The tumors presented as solitary lesions situated on the limbs (six lesions), trunk (four lesions), and head and neck (two lesions). The patients included six women and six men, whose ages ranged from 26 to 95 years, with a mean of 63 years. Breslow thickness varied from 0.48 mm to more than 12 mm, with a mean of more than 3.2 mm. Clinical follow-up for an average of 22 months showed one local recurrence, but no evidence of metastases yet. In all cases, there was a combination of myxoid and nonmyxoid areas. A minimum of 15% myxoid cross-sectional area was required for inclusion in the study, and up to 80% was observed. The pale blue mucin identified on hematoxylin and eosin staining was sensitive to hyaluronidase and positive for alcian blue in the 10 cases stained. Immunohistochemical staining was positive for S-100 in all 9 cases stained, positive for HMB-45 in 9 (90%) of 10, and negative for cytokeratin in all 9 cases in which myxoid melanoma remained in the block after previous sections. The presence of myxoid stroma did not define a biologically significant subgroup of melanoma. Only in cases with extensive (>50%) myxoid stromal effacement of the melanoma was there a major diagnostic hurdle. The diagnosis of primary cutaneous melanoma with myxoid features was seldom as problematic as metastatic myxoid melanoma. Positive S-100 stains, negative cytokeratin immunohistochemical stains, and hyaluronidase-sensitive alcian blue staining assisted in the diagnosis of this entity.

Adult↗

Dying dogma: the pathological diagnosis of epidermotropic metastatic malignant melanoma.

Distinguishing primary cancer from a metastasis is a fundamental task in surgical pathology that has crucial therapeutic and prognostic implications. When metastatic melanoma involves the skin and extends into the epidermis (epidermotropic), differentiating it from primary cutaneous melanoma may be particularly difficult. Early investigators dismissed this issue as a nonproblem and dogmatically declared that junctional change was requisite for the diagnosis of primary cutaneous melanoma. Epidermotropic metastases of malignant melanoma (EMMM) are now recognized to have many features in common with primary melanoma, which can include involvement of the dermal-epidermal junction, extension of the intraepidermal component beyond the dermal component, and even an epidermal-only pattern. This article traces the evolution in criteria used to diagnose EMMM and highlights why much of the original thinking is no longer accepted. Current concepts in EMMM morphology are elaborated and illustrated. The role of immunomicroscopy and molecular pathology in the detection of EMMM is also discussed.

Adult↗

Malicious masquerade: myxoid melanoma.

The morphological spectrum of malignant melanoma is broad. Unusual stromal changes can distract pathologists from the correct diagnosis. Fibroblastic, chondroid, osteoid, and myxoid stroma have been documented in melanomas. Myxoid melanoma is problematic--introducing carcinomas and soft tissue sarcomas into the differential diagnosis. This review examines the clinicopathologic aspects of myxoid malignant melanoma, with emphasis on its differential diagnosis.

Adult↗

Adult pityriasis rubra pilaris: a 10-year case series.

BACKGROUND: Pityriasis rubra pilaris (PRP) often has a devastating impact on the lives of patients. Descriptions of its histopathologic features are not uniform. Finding a successful therapy can be challenging. OBJECTIVE: Our purpose was to examine the histopathologic features and response of patients to our standard therapy of an oral retinoid and concomitant or later addition of low-dose weekly methotrexate. METHODS: A retrospective chart review was done on 24 patients with PRP seen from March 1986 to March 1996. Biopsy specimens from 19 patients were reexamined. Telephone follow-up was conducted to determine maintenance of remission. RESULTS: All patients had the adult acquired form of PRP. Biopsy specimens from nine patients were characterized by prototypical findings of PRP, while the others included both typical and other features. Twenty-two patients were treated with either isotretinoin, 40 mg twice daily, or etretinate, 25 to 75 mg/day. Six patients with more disabling involvement had low-dose weekly methotrexate ranging from 5 to 30 mg started concurrently. Five patients had weekly methotrexate added at a later time. Seventeen patients showed 25% to 75% response after 16 weeks of therapy. All patients whose skin cleared maintained their remission. CONCLUSION: Initial oral retinoid plus concurrent or later low-dose weekly methotrexate resulted in 25% to 75% improvement of PRP in 17 of 24 patients after 16 weeks of therapy. Some of the atypical features seen in biopsy specimens emphasize the importance of clinical and histopathologic correlation in establishing the diagnosis.

Administration, Oral↗

Mixed tumors and myoepitheliomas of soft tissue: a clinicopathologic study of 19 cases with a unifying concept.

We report 19 unusual cases of mixed tumors and myoepitheliomas arising in soft tissues. The neoplasms occurred in 12 males and seven females. The age at diagnosis ranged from 2 to 83 years (mean 35, median 30). Eight tumors arose in the upper limb, six in the lower limb, three in the trunk, and two in the head and neck region. Three cases involved both dermis and subcutis; the remainder arose in subcutaneous (13 cases) or deep subfascial soft tissue (three cases). The most common presenting complaint was a painless swelling, with duration ranging from 2 weeks to 1 year (median 2.5 months). Microscopically, the tumors were predominantly well circumscribed and lobulated. Six cases showed a focally infiltrative margin. Cardinal morphologic features included nests, cords, and ductules of epithelioid cells and/or nests of spindled cells within a hyalinized to chondromyxoid stroma. One tumor was predominantly composed of myoepithelial cells and devoid of epithelial differentiation (i.e., ductules). Cytoplasmic hyaline inclusions were noted in two cases; squamous differentiation was seen in one case. Osteoid production and/or metaplastic bone was observed in three tumors. Chondroid differentiation (usually mature) was seen in four cases. Adipocytic differentiation was seen in two tumors. Mitotic activity was variable but generally scant; atypical mitotic figures were not identified. By immunohistochemistry, 16 of 16 cases expressed pan-keratin; 16 of 17 S-100 protein; six of 14 alpha smooth muscle actin (IA4); two of 10 muscle specific actin (HHF-35); two of 10 desmin; three of 11 glial fibrillary acidic protein; and three of 16 epithelial membrane antigen. Clinical follow-up was available in 10 patients and ranged from 6 months to 20 years (mean 4.25 years, median 2 years). Two patients developed local recurrence; metastasis to lung and lymph nodes were observed in two additional patients. Both of the latter patients died. We believe that these findings expand the concept of cutaneous mixed tumors to include neoplasms composed predominantly of myoepithelial cells and to include tumors arising in deeper subcutaneous and/or subfascial tissues. The clinical behavior of such neoplasms, when arising in soft tissues, may be difficult to predict but is most often benign; however, a minority of lesions metastasize. Until larger studies with longer follow-up are available, treatment and prognostication are probably best based on criteria used in comparable salivary gland tumors.

Adult↗

Panniculitis: recent developments and observations.

Dermatopathologists rarely greet a biopsy of panniculitis with total confidence that a specific, definitive diagnosis will be rendered. As with many other areas in dermatopathology, our understanding of the pathogenesis of many forms of panniculitis is incomplete. This article examines a subset of panniculitis primarily from a pathogenetic standpoint, with the intention of providing a differential diagnosis for those cases in which ischemic changes are seen in the subcutis. The diverse group of conditions evoked by this approach also shares the distinction of having been the focus of nosologic and causative controversy, both historically and currently. In particular, stasis-associated sclerosing panniculitis, vascular calcification-cutaneous necrosis syndrome (calciphylaxis), oxalosis, and nodular vasculitis-erythema induratum are examined in depth. Erythema nodosum and variants, other granulomatous panniculitides, and panniculitides showing cytophagocytosis are also discussed with current perspectives.

Diagnosis, Differential↗

Eccrine gland infiltration by mycosis fungoides.

After identifying prominent eccrine infiltration by atypical lymphocytes in a biopsy of tumor stage mycosis fungoides (MF), we sought to determine the pattern of eccrine epithelial infiltration in MF. The frequency, intensity, and distribution of infiltration of eccrine gland structures, including acrosyringium, duct and coil epithelium, was studied by examining 71 biopsy specimens from 42 patients with MF in which eccrine structures were present. These were obtained from a retrospective review of pathologic specimens from Duke University Medical Center from 1992 and 1993. At least focal eccrine infiltration was noted in 23 of the 71 biopsy specimens (32%). Immunohistochemical confirmation of T-lymphocyte phenotype was performed in the 23 cases with positive reaction to antibodies CD3 and CD45RO and negative reaction with CD20. Folliculosebaceous units were present in 22 of the 71 biopsy specimens and were at least focally involved by MF in 11 (50%) in this series. A control group of biopsy specimens of reactive dermatoses were characterized by more superficial location of lymphocytes, with more spongiosis and epithelial degenerative changes. These findings further illustrate the epitheliotropic behavior of MF.

Adult↗

Human recombinant stem-cell factor induces melanocytic hyperplasia in susceptible patients.

BACKGROUND: Recombinant human stem-cell factor (SCF), a cytokine acting on hematopoietic progenitor cells, has potential for the treatment of several hematologic and oncologic disorders. In a hematology-oncology phase I trial of SCF, several patients had cutaneous hyperpigmentation at the SCF subcutaneous injection sites. OBJECTIVE: Our purpose was to investigate the pathogenesis of this hyperpigmentation phenomenon. METHODS: Skin biopsy specimens were obtained before, at the completion of, and after SCF therapy and were processed for histology, immunohistology, and electron microscopy. RESULTS: Skin at the site of SCF injection had an increased number of melanocytes, increased melanocytic dendrite extension, and melanin as compared with noninjected tissue. Immunohistochemical stains revealed an increase in staining with melanocyte-specific monoclonal antibodies HMB-45 and NKI/beteb, and a monoclonal antibody to the receptor for SCF, c-kit. CONCLUSION: Subcutaneous injection of SCF results in hyperplasia of melanocytes. SCF may be useful in the treatment of melanocytopenic disorders, but caution may be necessary in patients with disorders of melanocyte proliferation.

Antibodies, Monoclonal↗

Shadow cells in an intracranial dermoid cyst.

A case of an intracranial dermoid cyst containing shadow cells is presented. This case expands the group of lesions in which shadow cells, indicative of hair matrical differentiation, have been described.

Adult↗

Ber-EP4 immunoreactivity in normal skin and cutaneous neoplasms.

Ber-EP4 is an antibody raised against a cell membrane glycoprotein of, as yet, unknown function. In the skin, the ability to distinguish basal cell carcinoma from squamous cell carcinoma has been emphasized. Immunoreactivity in apocrine and eccrine secretory coil epithelium, Merkel cell carcinoma, and cutaneous mixed tumor has been reported. Having observed more widespread staining than previously reported, we sought to characterize further Ber-EP4 immunoreactivity by examining 76 formalin-fixed and paraffin-embedded proliferative epithelial skin lesions, 2 sections of fetal skin with developing adnexa, and frozen sections of skin from Mohs surgery procedures, using hematoxylin and eosin and Ber-EP4 immunostaining. In paraffin-embedded skin, matrical and outer sheath epithelium of vellus anagen follicles, inferior segment epithelium of vellus telogen follicles, and secretory coils of sweat glands stain with Ber-EP4, but anagen terminal follicle epithelium and eccrine and apocrine sweat ducts are negative. On frozen section, additional staining of eccrine ducts and cells in the outer sheath and matrix of the inferior segment of terminal follicles is noted. Basaloid epithelium of trichoepitheliomas, follicular induction over dermatofibromas, mammary Paget's disease, and selected other neoplasms showing eccrine or apocrine differentiation stain with Ber-EP4. These data indicate that in addition to basal cell carcinoma, Ber-EP4 staining may be seen in a variety of proliferative epidermal and adnexal lesions.

Adenoma, Sweat Gland↗