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Biomedical subjects

K F Helm

Publications and source records attributed to K F Helm.

At least 55 records · Page 3Linked to original sources
PubMed1994

Malignant melanoma with clinical and histologic features of Merkel cell carcinoma.

We describe a patient with malignant melanoma that resembled a Merkel cell carcinoma both clinically and histologically. Immunohistochemical studies showed focally positive staining with S-100 protein and strongly positive staining with HMB-45. Ultrastructural study confirmed the diagnosis by demonstrating premelanosomes and melanosomes. Although the tumor appeared to be clinically unimpressive, it was a deep melanoma with a Breslow level of 3.8 mm that necessitated aggressive treatment. Small cell melanoma must be considered in the differential diagnosis of small cell tumors, which also includes lymphoma, eccrine carcinoma, squamous cell carcinoma, and Merkel cell carcinoma. The diagnosis of amelanotic melanoma, including the small cell variant, may require electron microscopic studies.

Antibodies, Monoclonal↗
PubMed1994

Management of a hidradenoma with Mohs micrographic surgery.

BACKGROUND: Hidradenomas are adnexal tumors that may grow to be very large and frequently recur after excision. Malignant transformation and metastatic spread can occur and histologic distinction of benign from malignant hidradenomas can be very difficult. Some tumors with bland histology have demonstrated aggressive behavior. OBJECTIVE: To decide the benefits of management with Mohs micrographic surgery of large hidradenomas. METHODS: The literature was reviewed, including both the clinical course of the tumor and histologic features. The case of our report was interpreted in light of the review. RESULTS: Three stages of Mohs surgery were required for complete removal of the hidradenoma. The patient remains free of recurrence. CONCLUSION: This report highlights the difficulties in distinguishing benign from malignant hidradenomas and emphasizes the benefits of Mohs surgery for large or recurrent tumors.

Adenoma, Sweat Gland↗
PubMed1994

Granuloma annulare: an immunohistochemical study.

The monocyte/histiocytic response in granuloma annulare has not been extensively studied. We studied the immunohistochemical staining pattern in granuloma annulare by using a panel of markers for "histiocytic" cells including Ham 56, KP1, factor XIIIa, Mac 387, vimentin, and lysozyme. The infiltrate failed to stain with the histiocytic markers, except with antibodies against vimentin and lysozyme. Commonly used histiocytic markers for infectious, immunogenic, and foreign body granulomas fail to stain the infiltrate in granuloma annulare. We hypothesize that a locally derived, immunologically distinct population of histiocytes produces the reaction pattern of granuloma annulare.

Granuloma Annulare↗
PubMed1993

Deposition of membrane attack complex in cutaneous lesions of lupus erythematosus.

BACKGROUND: The membrane attack complex (MAC; C5b-9) localizes in the basement membrane zone (BMZ) of cutaneous lesions from patients with lupus erythematosus (LE) and has been implicated in the pathogenesis of this disease. OBJECTIVE: Our purpose was to compare the frequency of MAC deposition with that of immunoglobulin and C3 deposition (lupus band). METHODS: We studied 56 skin biopsy specimens from 42 patients with LE by direct immunofluorescence. RESULTS: MAC was deposited in a granular pattern at the BMZ in 29 of 38 biopsy specimens (76%) from lesional skin; 5 of 38 specimens (13%) had focal or weak segmental deposition and 4 of 38 (11%) were negative. In contrast, IgG, IgM, IgA, and C3 were detected in 16 of 38 specimens (42%), 30 of 38 (79%), 4 of 38 (11%), and 22 of 38 (58%), respectively. None of the uninvolved skin biopsy specimens was MAC positive, although 4 of 18 (22%), 5 of 18 (28%), 1 of 18 (6%), and 2 of 18 (11%) were positive for IgG, IgM, IgA, and C3, respectively. CONCLUSION: MAC deposition in lesional skin appears to be a relatively sensitive and specific marker for cutaneous LE and may be useful as an adjunct to the "lupus band" test.

Basement Membrane↗
PubMed1993

A clinical and pathologic study of histiocytosis X in adults.

BACKGROUND: Histiocytosis X is a neoplastic disorder of Langerhans cells that usually occurs in children. Because histiocytosis X rarely occurs in adults, the diagnosis can frequently be missed by both clinicians and pathologists. OBJECTIVE: The purpose of this investigation was to characterize the clinical and pathologic findings of histiocytosis X in adults. METHODS: A retrospective study of four adults with histiocytosis X was undertaken. Paraffin-embedded biopsy specimens were stained with a panel of antibodies including S-100, vimentin, Ham-56, leukocyte common antigen, proliferating cell nuclear antigen (PCNA), UCHL-1, CD43, and Ki-1. RESULTS: The predominant lesions were papules and pustules that usually involved the groin, axilla, and scalp. Histologically the infiltrate exhibited a periappendageal distribution. Strong positive staining for PCNA appeared to correlate with the clinical course. CONCLUSION: Histiocytosis X in adults has a predilection for skin sites rich in appendages and histologically shows a periappendageal infiltrate. PCNA staining of the histiocytes may indicate progressive disease and serve as a useful prognostic marker.

Adult↗
PubMed1993

Cutaneous metastases in patients with metastatic carcinoma: a retrospective study of 4020 patients.

BACKGROUND: Most previous studies have found that cutaneous metastases occur infrequently and are rarely present at the time the cancer is initially diagnosed. OBJECTIVE: We studied patients with metastatic cancer to determine the overall frequency of skin metastases, the frequency that these were the first sign of extranodal disease, and the clinical and histologic features of the cutaneous lesions. METHODS: A 10-year period of tumor registry files was searched for patients with metastatic carcinoma and melanoma. For patients with skin metastases, medical records and pathology reports were also examined. RESULTS: Of 4020 patients with metastatic disease, 420 (10%) had cutaneous metastases; in 306 of them the skin metastases were the first sign of extranodal metastatic Breast cancer and melanoma were the most common. Nodules were the most frequent clinical presentation, although inflammatory, cicatricial, and bullous lesions were also noted. Incisional metastases were common. Histologic findings most frequently revealed adenocarcinoma that was sometimes suggestive of the site of origin. After recognition of skin metastases, mean patient survival ranged from 1 to 34 months depending on tumor type. CONCLUSION: Cutaneous metastases are not uncommon and frequently are the first sign of extranodal metastatic disease, particularly in patients with melanoma, breast cancer, or mucosal cancers of the head and neck.

Adenocarcinoma↗
PubMed1993

Proliferating cell nuclear antigen distribution in keratoacanthoma and squamous cell carcinoma.

Histologic differentiation of keratoacanthoma (KA) and squamous cell carcinoma (SCC) is often difficult despite well-delineated histopathologic criteria. This has prompted a search for more objective methods to differentiate these two lesions. In the present study, we immunohistochemically examined the distribution of proliferating cell nuclear antigen (PCNA)-positive cells in 11 cases of KA, 7 cutaneous SCC, and 2 atypical squamous proliferations (for which a definitive diagnosis could not be made on routine histology) using a commercially prepared anti-PCNA monoclonal antibody. We found PCNA-positive cells predominantly in the periphery of squamous nests in KA. In contrast, SCC showed a diffuse staining pattern with PCNA-positive cells seen throughout squamous nests. Determining the pattern of PCNA-positive cells is easy, does not require cell counting, and may provide additional histochemical data facilitating the distinction between KA and SCC.

Antibodies, Monoclonal↗
PubMed1993

Verruciform xanthoma in an immunocompromised patient: a case report and immunohistochemical study.

The etiology of verruciform xanthoma, a rare lesion that usually occurs in the oral mucosa, is unknown. A viral etiology has been speculated since extraoral lesions usually occur in the genitalia. We present, to the best of our knowledge, the first reported case of verruciform xanthoma in an immunocompromised patient with chronic graft versus host disease. Immunohistochemical studies showed a few Ham 56 (a macrophage marker) positive foam cells, both in the dermis and within the epidermis, supporting a role for an epidermal process in production of the foam cells. Staining for human papillomavirus protein (HPV) showed reactivity of some of the nuclei in the dermal histiocytes, but in situ hybridization for HPV types 6/11, 16/18, and 31, 33 was negative. These results support an epidermal process as the stimulus for the foam cell formation but fail to demonstrate HPV as the cause.

Adult↗
PubMed1993

Palisading cutaneous fibrous histiocytoma. An immunohistochemical study demonstrating differentiation from dermal dendrocytes.

The palisading cutaneous fibrous histiocytoma is a unique benign spindle cell tumor that often occurs in an acral location. Histologic findings feature nuclear palisading reminiscent of a schwannoma. Previous studies have suggested that this tumor may be a variant of a dermatofibroma. We performed immunohistochemical staining with a panel of antibodies including neurofilament, S100 protein, factor XIIIa, epithelial membrane antigen, Leu-7, desmin, and vimentin. We found positive staining with factor XIIIa and vimentin, suggesting connective tissue differentiation for this tumor.

Adult↗
PubMed1992

Malignant lymphoma and leukemia with prominent ulceration: clinicopathologic correlation of 33 cases.

BACKGROUND: The clinical and pathologic findings in patients with malignant lymphomas who presented with prominent cutaneous ulcers are described. OBJECTIVE: Our purpose was to determine the histologic findings, type, and prognosis of lymphomas with cutaneous ulcers. METHODS: Thirty-three patients (20 with cutaneous T-cell lymphomas, 10 with other non-Hodgkin's lymphomas, and 3 with leukemia) were retrospectively studied. RESULTS: All patients had a poor prognosis; 23 died within 9 months after the onset of the ulcers. Patients with non-Hodgkin's lymphoma had a worse prognosis, had a higher incidence of systemic involvement, and more often had ulcers as an initial manifestation of lymphoma than did the patients with cutaneous T-cell lymphoma. The histopathologic findings ranged from a nonspecific inflammatory infiltrate to ulcers with marked adjacent epidermal epidermotropism to ulcers with an angiocentric infiltrate. CONCLUSION: A variety of lymphomas may cause cutaneous ulceration. Adequate sampling of these ulcers is necessary for diagnosis. The average life expectancy after ulcer formation is 21 months.

Adult↗
PubMed1992

Pyoderma gangrenosum-like ulcer in a patient with large granular lymphocytic leukemia.

Large granular lymphocytic leukemia refers to a clonal expansion of lymphocytes that have abundant cytoplasm and azurophilic granules. The disease is characterized clinically by chronic neutropenia and it may be associated with recurrent pyogenic infections. Except for these infections, cutaneous manifestations of this disease have not been well characterized. We describe a patient with large granular lymphocytic leukemia, which was confirmed by molecular genetics studies, who had a pyoderma gangrenosum-like ulcer on his leg. Results of an evaluation of the histologic characteristics and the leukocytic immunophenotype of a skin biopsy specimen from the ulcer demonstrated large granular lymphocytes within the blood vessels. Cutaneous ulceration may be a manifestation of large granular lymphocytic leukemia, and this disease should be considered when diagnosing patients with otherwise unexplained pyoderma gangrenosum-like ulcers of the skin.

Complement C3↗
PubMed1992

Benign lymphocytic infiltrate of the skin: correlation of clinical and pathologic findings.

In a retrospective study of 137 biopsy specimens of skin from 137 patients (69 men and 68 women) that had been obtained between 1972 and 1989 at our institution and that had perivascular and periappendageal lymphocytic infiltrates characteristic of those described as benign lymphocytic infiltrate (BLI), we determined the specificity of the histologic diagnosis and the correlation with clinical data. The final diagnoses, based on clinical and laboratory data and histologic findings, were BLI (59), possible BLI (7), lupus erythematosus (LE) (12), possible LE (7), procainamide-induced LE (1), insect bites (9), possible insect bites (3), polymorphous light eruption (4), lymphocytoma (4), urticaria (4), and indeterminate or miscellaneous diagnoses (27). BLI is a clinical and histologic syndrome that can be heterogeneous in origin. We recommend careful evaluation to exclude other disorders such as LE, polymorphous light eruption, lymphocytoma, and insect bites. Direct immunofluorescence microscopy and immunophenotypic studies may help distinguish BLI from LE.

Adult↗
PubMed1992

Immunohistochemical stains in extramammary Paget's disease.

The histologic and immunohistochemical characteristics of 49 skin biopsy specimens from 49 patients with extramammary Paget's disease were studied. Patients with extramammary Paget's disease with and without underlying malignant disease were identified. Associated malignant lesions, present in 16 patients (33%), were transitional cell carcinoma of the bladder (n = 8), adenocarcinoma underlying the skin (n = 3), adenocarcinoma of the anus (n = 1), adenocarcinoma of the vulva (n = 1), apocrine carcinoma (n = 1), prostate carcinoma (n = 1), and carcinoma metastatic to the lung (n = 1). The main histologic feature was the presence of Paget's cells, predominantly at the base of the epidermis. In 6% of the cases, well-defined nests of large Paget's cells mimicked melanocytic nests. Carcinoembryonic antigen and Cam 5.2 (a monoclonal antibody that stains 40-kDa, 45-kDa, and 52.5-kDa low molecular weight keratins) were localized to the Paget's cells in 42 of 45 (93%) and 29 of 41 cases (71%), respectively. Forty-four of 46 lesions (96%) were mucin positive, as determined by Hale's colloidal iron stain. Absence of staining for colloidal iron and carcinoembryonic antigen occurred somewhat more frequently in patients with underlying malignant disease than in patients without tumors (13% vs. 0% mucin negative and 13% vs. 3% carcinoembryonic antigen negative, respectively). Although immunohistochemical staining for low molecular weight keratin may be used to confirm the diagnosis of extramammary Paget's disease, Cam 5.2 is not as sensitive as the colloidal iron or carcinoembryonic antigen stain.

Aged↗
PubMed1992

Granulomatous slack skin: a clinicopathological and immunohistochemical study of three cases.

Three cases of granulomatous slack skin (GSS), a rare variant of T-cell lymphoma, are reported. Immunohistochemical studies using a panel of 16 antibodies were carried out on both frozen tissue and tissue embedded in paraffin wax to characterize the infiltrate. A routine immunoperoxidase technique was used to identify T cells (UCHL1, CD45R0), B cells (L26, 4KB5 [CD45R]), S100 protein-positive cells, monocytes/macrophages (Mac-387, KP1 [CD68]), and dermal dendrocytes (factor XIIIa) in paraffin sections. A close association was found between UCHL1-positive T cells and KP1-positive giant cells. A number of S100-positive cells and factor XIIIa-positive cells were present in the infiltrate from all three patients. The lymphocytes in two of the patients were predominantly of the helper T-cell phenotype. Giant cells from all three patients stained with KP1 (CD68) and Leu M3 (CD14). These studies confirm that the infiltrate in GSS is predominantly a T-cell disorder associated with monocyte-derived cells rather than with resident dendritic macrophages.

Adult↗