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O P Sangüeza

Publications and source records attributed to O P Sangüeza.

17 recordsLinked to original sources
PubMed2001

Postirradiation pseudosclerodermatous panniculitis.

Pseudosclerodermatous panniculitis is an unusual variant of panniculitis that results as a complication of megavoltage radiotherapy. Four women developed this unusual entity on the anterior chest and abdominal skin after receiving megavoltage therapy for either breast carcinoma or painful bone metastases from breast carcinoma. Histopathologically, the epidermis and dermis of the involved area showed little or no evidence of radiodermatitis. The main findings were confined to the subcutaneous tissue and consisted of thickened, sclerotic septa composed of both thick and thin collagen bundles, and a lobular panniculitis characterized by lipophagic granulomas and scattered lymphocytes and plasma cells. Additionally, one of the cases showed markedly dilated vascular spaces with the appearance of lymphatics in the upper part of the dermis. Pseudosclerodermatous panniculitis after irradiation is an unusual cutaneous complication of megavoltage radiotherapy that should be distinguished from subcutaneous metastatic disease, cellulitis, or connective tissue diseases involving the subcutaneous fat. The differential diagnosis can be established on the basis of the characteristic histopathologic features of postirradiation pseudosclerodermatous panniculitis.

Adult↗
PubMed1998

Angiocentric cutaneous T-cell lymphoma of childhood (hydroa-like lymphoma): a distinctive type of cutaneous T-cell lymphoma.

BACKGROUND: Angiocentric cutaneous T-cell lymphomas of childhood (ACTCLC) are an unusual type of T-cell lymphomas that present with a vesiculopapular eruption mimicking hydroa vacciniforme. Most patients have been children from Asia and Latin America. OBJECTIVE: The purpose of this study was to describe four cases of ACTCLC; to discuss its clinical, histopathologic, and immunohistochemical features; to consider its possible relationship to the Epstein-Barr virus (EBV); and to clarify its classification within the spectrum of angiocentric lymphomas. METHODS: The clinical, histopathologic, and immunohistochemical features of four cases of ACTCLC were identified and analyzed. In addition in situ hybridization for EBV was performed in all cases. RESULTS: The clinical features were similar to previous cases reported under different names, such as hydroa-like lymphomas, edematous, scarring vasculitic panniculitis. Histologically, all showed angiocentric infiltrates composed mainly of T cells. In all cases there were variable numbers of CD30+ cells. The EBV was present in three of the cases. CONCLUSION: ACTCLC is a distinct type of T-cell lymphoma. It affects mainly children, and the EBV appears to play a role in the pathogenesis of this disease.

Child↗
PubMed1998

Neoplasms with neural differentiation: a review. Part II: Malignant neoplasms.

Malignant peripheral nerve sheath tumors (MPNSTs) encompass a wide and unusual group of neoplasms with features of neural differentiation. They most commonly present as spindle cell neoplasms and it can be difficult to differentiate them from other spindle cell neoplasms such as leiomyosarcomas, fibrosarcomas and synovial sarcomas. Strict criteria need to be applied in order to make the diagnosis of MPNSTs. Helpful features include contiguity with a nerve or an association with von Recklinghausen disease. The use of immunohistochemical stains may also help to confirm the diagnosis. Markers such as S-100 protein, neurofilament, epithelial membrane antigen and Leu-7 (CD57) are frequently used to assess neural differentiation in these neoplasms. In addition to the spindle cell pattern, MPNSTs may also display an epithelioid pattern. Rarely, other elements may be seen including glands in the so-called glandular MPNST or muscle in triton tumors. In more unusual cases cartilage, adipose tissue and even bone are present. Also included in the group of MPNSTs are the peripheral neuroepithelial tumor, neurotropic or desmoplastic melanomas and malignant granular cell tumors. MPNSTs are highly aggressive tumors and should be treated accordingly.

Adult↗
PubMed1997

Follicular mycosis fungoides: a clinicohistopathologic study.

BACKGROUND: Follicular mycosis fungoides (FMF) is a recently described variant of cutaneous T-cell lymphoma, histopathologically characterized by infiltrates of atypical CD4+ T lymphocytes around and within the epithelium of the hair follicles (folliculotropism). To date, only four cases of FMF have been reported. OBJECTIVE: Our goal was to identify cases of FMF and compare them with those previously reported. METHODS: The clinical and histopathologic features of three cases of FMF were analyzed. In addition, in one case immunohistochemical analysis in paraffin-embedded and frozen tissue as well as genotypic studies were performed. RESULTS: The three reported cases showed typical histologic findings of FMF, namely, perifollicular and intrafollicular infiltrates of atypical lymphocytes, in the absence of either epidermotropism or follicular mucinosis. Clinically, the lesions were similar to classic MF, but also contained follicular papules. Immunohistochemistry and gene rearrangement studies showed findings similar to classic MF. CONCLUSION: FMF is a rare variant of cutaneous T-cell lymphoma. Including our three cases, only seven patients have been reported. We hypothesize that the follicular epithelium in patients with FMF may express increased levels of skin-selective homing receptors and adhesion molecules. These may be involved in the induction of the folliculotropism of atypical lymphocytes.

Female↗
PubMed1997

Malignant glomus tumor of the thumb: a case report.

Glomangiosarcoma is a rare malignant variant of the glomus tumor (GT). It has been reported in different anatomical locations, with only 1 report of its localization to the hand, despite the fact that its benign counterpart is most frequently found there. There is only 1 report of glomangiosarcoma that has metastasized. Special attention should be paid to GTs that are not well circumscribed, since the possibility of persistence and malignant transformation is increased in these lesions. The treatment of choice for glomangiosarcomas is wide local excision.

Adult↗
PubMed1997

Erythema elevatum diutinum: a clinicopathological study of eight cases.

Erythema elevatum diutinum (EED) is a rare cutaneous condition that initially presents as leukocytoclastic vasculitis (LCCV) of the skin and later resolves with fibrosis. In addition to the LCCV, EED may show features reminiscent of other entities. For example, it may mimic lesions of dermatofibroma, granuloma annulare, granuloma faciale, or dermatitis herpetiformis. For this study, we reviewed the clinical records and 13 skin biopsies in eight patients with EED. One of the patients had concurrent pityriasis rubra pilaris, and another developed lesions of EED following and at the sites of mosquito bites; these associations have not been noted previously. In addition to such typical histopathological features as diffuse dermal involvement by neutrophils, eosinophils, and leukocytoclastic vasculitis, we also found two unusual patterns. The first was characterized by palisaded necrotizing granulomas, as previously described and associated with Churg-Strauss granuloma; the second condition simulated a pyogenicgranuloma--like lesion.

Adult↗
PubMed1997

Metastatic Crohn's disease.

Metastatic Crohn's disease is the term used for granulomatous lesions of Crohn's disease involving sites other than the gastrointestinal tract. Metastatic Crohn's disease has been considered uncommon, when in actuality it may simply be underdiagnosed or misdiagnosed since the clinical findings can be different. We report on three patients with this condition: one with generalized plaques, another with perineal and perianal ulcerations, and a third with a painless forearm nodule.

Adult↗
PubMed1997

Primary cutaneous immunocytoma: report of an unusual case with secondary spreading to the gastrointestinal tract.

Cutaneous immunocytoma are low-grade B-cell lymphomas, which affect the skin either primarily or secondarily. Primary cutaneous immunocytomas usually present with one or a small number of lesions, mainly in the extremities. They generally remain confined to the skin. Histologically, there are polymorphous infiltrates of cells, in which the presence of monoclonal plasma cells is characteristic. We describe a case of cutaneous immunocytoma with secondary spread to the gastrointestinal tract.

Aged↗
PubMed1997

Anaplastic carcinoma occurring in association with a mucinous cystic neoplasm of the pancreas.

Anaplastic carcinomas of the pancreas are considered variants of ductal adenocarcinoma. They typically occur in elderly men. They have rarely been reported to occur in association with mucinous cystic neoplasms of the pancreas. We report a case of anaplastic carcinoma occurring in association with a pancreatic mucinous cystic neoplasm, borderline-type, in a 25-year-old woman who presented with lymph node and hepatic metastases.

Adult↗
PubMed1996

Absence of Epstein-Barr virus in lymphomatoid papulosis. An immunohistochemical and in situ hybridization study.

BACKGROUND AND DESIGN: Lymphomatoid papulosis (LyP) and cutaneous Hodgkin's disease share many clinical, histopathologic, and immunohistochemical features. Epstein-Barr virus (EBV) has been implicated in the pathogenesis of several lymphoid malignancies, including Hodgkin's disease. Given the similarities between LyP and Hodgkin's disease, we asked if EBV could be detected in lesions of LyP. We examined 31 specimens of LyP that were obtained from 24 patients for evidence of EBV by in situ hybridization to EBER1 transcripts and for immunohistochemistry of viral latent membrane protein 1 (LMP1). RESULTS: In no instance there was there any evidence of EBV gene products by either in situ hybridization or immunohistochemistry. CONCLUSIONS: The absence of EBV in LyP suggests that this virus is not operative in the pathogenesis of LyP. Furthermore, it suggests that LyP and Hodgkin's disease may not share the same molecular mechanisms despite their phenotypic similarities.

Herpesvirus 4, Human↗
PubMed1995

Juvenile xanthogranuloma: a clinical, histopathologic and immunohistochemical study.

Juvenile xanthogranuloma (JXG) is a benign histiocytic proliferation of uncertain histogenesis which usually resolves spontaneously. Histopathologically, classic lesions are characterized by diffuse proliferations of foamy histiocytes, many of which may be multinucleated (Touton cells), admixed with lymphocytes and eosinophils. Histologic variants of JXG, perhaps representing evolving lesions, may lack these typical histopathological features, showing diffuse infiltrates of non-foamy mononuclear histiocytes without Touton cells, posing problems in differentiation from other histiocytic or melanocytic proliferations. Immunohistochemically, JXG is characterized by variable expressions of several histiocytic markers as well as the absence of staining for S100 protein. To assess better the spectrum of histopathological and immunohistochemical features of JXG, we studied nine cases of classic or histologic variant of JXG. The cases were evaluated by light microscopy and with an extensive battery of antibodies. All 9 cases, regardless of their light microscopic appearance, showed markedly positive staining with histiocytic markers including CD68, HAM56, cathepsin B and vimentin, but did not stain for S100 protein. Antibodies to factor XIIIa stained positively in 8 cases while staining for other markers was variable. Our results suggest that the histiocytes in JXG lesions have macrophagic differentiation, probably representing a reactive process to an unknown stimulus.

Adult↗
PubMed1994

Multiple primitive neuroectodermal tumors.

Primitive neuroectodermal tumors are rare, highly aggressive neoplasms that affect both sexes and occur in all age groups. They are a large group of neoplasms with neuroepithelial differentiation, including cutaneous neuroblastomas. Histopathologically they are characterized by a rather uniform population of small, dark cells, with or without Homer Wright rosettes. Immunohistochemically they stain for one or more of the reputed neural markers. Ultrastructurally they show interdigitating processes containing neurosecretory granules, intermediate filaments, and microtubules. We describe a patient with unusual multiple peripheral neuroectodermal tumors localized to the skin, with benign biologic behavior. The patient related the appearance of new lesions for several years without evidence of visceral dissemination or systemic complications. The histopathologic, immunohistochemical, and ultrastructural findings support the diagnosis of a peripheral neuroectodermal tumor.

Diagnosis, Differential↗
PubMed1994

Merkel cell carcinoma. Histopathology, immunohistochemistry, and cytogenetic analysis.

BACKGROUND: Merkel cell carcinoma (MCC) is a cutaneous neoplasm, histopathologically difficult to differentiate from other small blue cell neoplasms. Immunohistochemical and ultrastructural analyses are usually helpful in differentiating these neoplasms. Recently, cytogenetic analysis has emerged as a potential tool in the diagnosis of solid neoplasms, including MCC. OBJECTIVE: To describe the immunohistochemical and cytogenetic features of a case of primary MCC and to review the cytogenetics literature on MCC. METHODS: Formalin-fixed tissue was processed routinely and labeled with a battery of antibodies. Metaphase cells from fresh tissue were prepared by Giemsa banding. RESULTS: Histopathologically, there were irregular aggregates of pyknotic cells with little cytoplasm. Immunohistochemically, the neoplastic cells stained positive for neurofilament, cytokeratin, neuron-specific enolase, and epithelial membrane antigen. Leucocyte common antigen, S-100, 013, and chromogranin were negative. Karyotyping of neoplastic cells showed loss of chromosome Y (-Y). CONCLUSIONS: Coexpression of cytokeratin and neurofilament is characteristic of MCC and allows it to be differentiated from similar neoplasms. The significance of Y chromosome loss is unclear. Further cytogenetic analyses are warranted to identify genetic mutations significant to the pathogenesis of MCC.

Aged↗