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D M Parham

Publications and source records attributed to D M Parham.

At least 91 records · Page 5Linked to original sources
PubMed1994

Immunohistochemical analysis of the distribution of MyoD1 in muscle biopsies of primary myopathies and neurogenic atrophy.

The expression of the myogenic determination gene MyoD1 plays a primary role in the commitment of primitive mesenchymal cells to a striated muscle lineage and is down-regulated during later stages of differentiation. To determine the potential role of this gene in myopathic conditions, we examined its expression by means of immunohistochemical analysis, using a series of muscle biopsies from 14 patients with a variety of primary myopathies and neurogenic disorders. Utilizing the avidin-biotin-complex technique, cryostat sections were stained with monoclonal antibody 5.8 A, which we have previously described as having a high level of specificity for tumors with rhabdomyoblastic differentiation. Of special interest was the observation in 4 of 8 cases of neurogenic atrophy of varying levels of cytoplasmic positivity of muscle fibers, appearing to correlate with their degree of atrophy, in addition to weak nuclear staining. Muscle biopsies from 2 patients with Duchenne's muscular dystrophy and 2 patients with autoimmune inflammatory myopathies demonstrated various levels of nuclear positivity in scattered foci that appeared to correlate with areas of regeneration. A biopsy from a single case of neurogenic atrophy secondary to infantile spinal muscular atrophy (Werdnig-Hoffmann's disease) demonstrated diffuse but relatively weak staining of myofiber nuclei, in contrast to sections of normal striated muscle and muscle biopsies from patients with unexplained myoglobinuria, which exhibited only minimal amounts of staining. These data are compatible with observations that MyoD1 expression is related to electrical activity and muscle regeneration.

Adult↗
PubMed1994

A new cytogenetic finding in an epithelioid sarcoma, t(8;22)(q22;q11).

We report a new translocation t(8;22)(q22;q11) in a single case of epithelioid sarcoma. The band involved in chromosome 22 is the same found in 70-80% of the case of Ewing's sarcoma/peripheral neuroepithelioma (PNET) with cytogenetic characterization. The histologic characteristics of this tumor were typical for epithelioid sarcoma. Immunohistochemical stains were also entirely consistent with this diagnosis, including non-reactivity with P30/32MIC2, a specific marker for Ewing's sarcoma/primitive neuroepithelioma.

Child↗
PubMed1994

Increased confidence of diagnosis of Ewing sarcoma using T2-weighted MR images.

To assess whether magnetic resonance imaging could assist in diagnosing Ewing sarcoma, we retrospectively analyzed T1- and T2-weighted images of 24 consecutive solitary lytic bone lesions, including 18 cases of histologically proven Ewing sarcoma, and six aggressive-appearing benign lesions including eosinophilic granuloma and osteomyelitis (3 cases each). Images were obtained using a (1.0T) Siemens GBSII system. No signal intensity differences were noted among the various lesions on T1-weighted images. The observed differences in T2-weighted marrow signal intensities were scored on a 5-point scale (5 = water, 3 = fat, and 1 = muscle) and then histologically correlated. Sixteen of 18 Ewing sarcomas showed homogeneous T2-weighted signal isointense with fat and two were heterogeneous. Signals for all 6 benign lesions were homogeneous and more intense than fat on T2-weighted images. All Ewing sarcomas had associated soft tissue masses whereas, only one benign lesion, an eosinophilic granuloma had a small soft tissue component. In our patient population, a homogeneous intramedullary T2-weighted signal isointense with fat, and the presence of an associated soft tissue mass helped differentiate Ewing sarcoma from benign lytic lesions. The reproducibility of these results requires testing in larger series of patients using a variety of MR imaging equipment of differing field strengths.

Adolescent↗
PubMed1994

Correlation of pathologic features with clinical outcome in pediatric adrenocortical neoplasia. A study of a Brazilian population. Brazilian Group for Treatment of Childhood Adrenocortical Tumors.

Although the relationship between pathologic features and clinical outcome is well established in adult adrenocortical neoplasms, the prognostic value of these features in pediatric adrenocortical neoplasms (PACN) is unclear. In a series of PACNs from 54 Brazilian children, the authors retrospectively investigated the prognostic value of histologic classification, ploidy, proliferative index, and size (as tumor weight or greater diameter). Histologic classification was most predictive of clinical behavior: there were no failures in 11 adenomas, 5 failures in 27 low-grade carcinomas, and 9 failures in 16 high-grade carcinomas (P = .0003). Tumor weight was predictive of failure in tumors weighing > or = 100 versus < 100 g (P = .04), and a trend was found toward failure among tumors measuring > or = 5 cm, as opposed to those < 5 cm (P = .07). Proliferative index was marginally related to failure (P = .05 at < 11% vs. > or = 11% and .07 at < 10% vs. > or = 10%), and ploidy was not significantly predictive of outcome (P = .25). Histologic type and tumor weight were the most reliable predictors of outcome in PACN.

Adrenal Cortex Neoplasms↗
PubMed1994

Solid alveolar rhabdomyosarcomas with the t(2;13). Report of two cases with diagnostic implications.

Two patients having rhabdomyosarcomas with the recently described "solid variant" pattern of alveolar rhabdomyosarcoma are reported. Both tumors had aggressive cytologic features with monotonous sheets of round nuclei, but without fibrous septa, and both had been initially classified as embryonal rhabdomyosarcomas. Cytogenetic analyses of tumor explants from both cases revealed the t(2;13) chromosomal aberration typical of alveolar rhabdomyosarcoma. Both patients died of metastases, despite aggressive surgical and adjuvant therapy. This report represents the first karyotypic analyses of solid alveolar rhabdomyosarcomas and supports the inclusion of these tumors in the alveolar category despite the lack of fibrous septa.

Adolescent↗
PubMed1994

The clinicopathologic spectrum of putative extrarenal rhabdoid tumors. An analysis of 42 cases studied with immunohistochemistry or electron microscopy.

The existence of extrarenal rhabdoid tumor (ERRT) as a discrete pathologic entity has been controversial despite frequent reports of its occurrence. We performed immunohistochemistry, electron microscopy, or both on 42 cases with this diagnosis sent in consultation to us. Only 12 of the 42 neoplasms had the histological findings of "classic" malignant rhabdoid tumor of the kidney; the remainder displayed a variety of neural, epithelial, myoid, mesenchymal, or ependymal patterns. Electron microscopy also showed that most possessed neural, epithelial, or ependymal features. Immunohistochemistry generally revealed marked polyphenotypia, with immunoreactivity to a wide array of antibodies against neural, epithelial, glial, and myogenic markers. A specific tissue-based diagnostic category could not be assigned in only 11 of the 42 cases, seven of which lacked material for a comprehensive ultrastructural or immunohistochemical study. We conclude that tumors currently diagnosed as ERRT represent a heterogeneous group of neoplasms that may form unique subsets of known entities within the specific site where they arise or that may defy classification into a specific alternative category. Our findings lead us to believe that the term ERRT is not valid as representing a specific diagnostic entity and to prefer the term "poorly differentiated neoplasm with rhabdoid features" for undifferentiated tumors.

Abdominal Neoplasms↗
PubMed1994

Monoclonal antibodies against a 97-kilodalton antigen from Aspergillus flavus.

We prepared a panel of five monoclonal antibodies (MAbs) directed against Aspergillus flavus that all reacted against one 97-kDa antigen by western blot (immunoblot). Flow cytometry demonstrated that these antibodies bound (in increasing degrees) to all morphologic stages of A. flavus growth: conidia, swollen conidia, and hyphae. Cross-reactivity among species was examined by enzyme-linked immunosorbent assay of fungal culture filtrates. Four MAbs reacted with 10 of 11 A. flavus isolates, and the fifth one reacted with 9 of them. One MAb also reacted with A. fumigatus, two reacted with A. niger, A. wentii, and A. nidulans, and all five reacted with A. ochraceus. None reacted with A. terreus, A. glaucus, A. versicolor, or a Penicillium species. Each MAb bound to A. flavus hyphae in formalin-fixed paraffin sections of a muscle biopsy from a confirmed human case of invasive aspergillosis. In summary, these MAbs identified a 97-kDa antigen found on A. flavus that is both surface bound and an exoantigen. Either the same or a cross-reacting antigen is present in A. fumigatus and other Aspergillus species.

Animals↗
PubMed1994

Synovial sarcoma in children and adolescents: the St Jude Children's Research Hospital experience.

PURPOSE AND METHODS: We reviewed the clinical records and pathologic findings of 37 children and adolescents with synovial sarcoma treated at our institution over a 30-year period to evaluate the prognostic significance of tumor size, invasiveness, histology, and other features. RESULTS: The 20 male and 17 female patients with synovial sarcoma had a median age of 13.7 years at diagnosis. Primary tumor sites were the extremities (n = 27), trunk (n = 8), and head and neck (n = 2). Disease stage (clinical group) was as follows: group I, n = 21; group II, n = 7; group III, n = 4; and group IV, n = 5. Nineteen patients had invasive (T2) lesions, 20 had tumors more than 5 cm in diameter, and 14 had histologic grade 3 lesions. The estimated 5-year survival rate (+/- SE) for patients with group I or II disease was 80% +/- 9%, compared with 17% +/- 15% for those with group III or IV tumors (P = .0003). An exact log-rank test, adjusted for clinical group, showed that tumor invasiveness and grade independently predicted overall and progression-free survival (P < .05); tumor size was significantly correlated with progression-free survival. A borderline significant relationship with overall survival was found for both tumor size and histologic subtype (P = .09). CONCLUSION: A controlled trial of adjuvant chemotherapy is merited in children with resected synovial sarcoma (clinical group I or II) who present with unfavorable clinicopathologic features such as large, invasive, or grade 3 lesions. Children with unresected or metastatic disease fare poorly despite multimodality therapy and require novel treatment approaches.

Adolescent↗
PubMed1994

The molecular biology of childhood rhabdomyosarcoma.

Rhabdomyosarcomas comprise a biologically heterogeneous group of childhood malignancies that are histologically characterized by varying degrees of differentiation, ranging from uncommitted primitive mesenchymal cells to fetal myotubes. This differentiation pattern is reflected in the behavior of the tumor cells in vitro and can be manipulated by the addition of various biological and chemical agents to the intercellular milieu. Recent studies have documented some of the genetic and phenotypic events that occur under these conditions. In addition, the use of cell lines has facilitated the identification of characteristic karyotypic abnormalities and DNA transcriptional activators that are of potential diagnostic importance. Alterations of tumor-suppressor and multidrug-resistance genes have also been described, and they portend identification of susceptible families and potential therapeutic strategies to deal with this clinically aggressive family of childhood neoplasia. These developments herald an increasing utility of molecular biology in the diagnosis and treatment of pediatric sarcomas and necessitate pathologists' familiarity with this subject.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1994

Myogenic regulatory protein expression in adult soft tissue sarcomas. A sensitive and specific marker of skeletal muscle differentiation.

Myogenic regulatory protein (MyoD1) is a DNA-binding nuclear protein that initiates myogenesis in mesenchymal stem cells. Its expression has proved a very sensitive marker of myogenic differentiation in malignant tumors of childhood. In this study, the reliability of MyoD1 expression as marker of skeletal muscle differentiation has been tested in 38 cases of adult-type sarcomas. Frozen sections were stained with the monoclonal antibody 5.8A (MAb 5.8A) developed against recombinant wild-type murine MyoD1. Routinely processed formalin-fixed sections from the same cases were reviewed and immunostained with a panel of antibodies commonly used to detect muscle differentiation: myoglobin, fast-myosin, desmin, muscle-specific actin, alpha-smooth muscle actin. Four cases positively stained with MAb 5.8A: three were high-grade spindle cell sarcomas, the fourth case was an alveolar soft-part sarcoma. Only tumors in which skeletal muscle histogenesis was inferred on the basis of histology and/or immunohistochemistry with conventional muscle markers stained positively for MAb 5.8A. All the other tumors tested, including leiomyosarcomas (11), liposarcomas, (10, including four dedifferentiated liposarcomas), fibrosarcomas (three), malignant fibrous histiocytomas (two), synovial sarcomas (two), and malignant peripheral nerve sheath tumors (two), were negative for MAb 5.8A. The high level of sensitivity and specificity of MyoD1 expression indicates the value of this marker in the diagnosis of soft tissue sarcomas.

Adolescent↗
PubMed1993

Bilateral Wilms tumor. Review of outcome, associated abnormalities, and late effects in 36 pediatric patients treated at a single institution.

BACKGROUND: Patients with bilateral Wilms tumor have an increased incidence of associated abnormalities and nephrogenic rests and require individualized multimodality therapy for cure. The authors reported the associated abnormalities, outcome, complications, and late effects of treatment in a group of children with bilateral Wilms tumor treated at St. Jude Children's Research Hospital, Memphis, Tennessee, over a 28-year period. METHODS: The records of 36 consecutive pediatric patients diagnosed with bilateral Wilms tumor between 1962-1990 were analyzed. Biopsy material was also reviewed, with particular emphasis on characterization of nephrogenic rests and histology. RESULTS: Twenty-nine patients had synchronous tumors and 7 had metachronous lesions. Associated physical abnormalities were present in 12 patients and involved the genitourinary, cardiovascular, integumentary, and musculoskeletal systems. The overall survival for patients with metachronous tumors (71%) was similar to that for those with synchronous tumors (70%). There was no effect of age or the presence of nephroblastomatosis. Two patients with synchronous tumors initially treated with nephrectomy eventually required bilateral nephrectomies for contralateral recurrence after chemotherapy and radiation therapy. Nephrogenic rests were present in 22 of 30 evaluable patients. Two of three patients with metachronous tumors had intralobar nephrogenic rests. Bilateral renal salvage procedures were demonstrated to be technically feasible and effective in controlling disease without compromising renal function or survival. Late effects included scoliosis in three patients treated before 1970, cardiomyopathy in one patient who received 300 mg/m2 doxorubicin and 12 Gy pulmonary irradiation, and benign tumors in two patients, one of whom also had a bowel obstruction. Serum creatinine, urea nitrogen, and blood pressure were normal in 23 of 26 survivors. CONCLUSIONS: The authors' experience supports a favorable outcome with minimal late effects for patients with bilateral Wilms tumor who receive individualized therapy at pediatric oncology centers.

Child↗
PubMed1993

Primary extracranial rhabdoid tumors. Clinicopathologic features and response to ifosfamide.

BACKGROUND: Malignant rhabdoid tumor (MRT) is an aggressive, invariably lethal tumor that is resistant to multimodal therapy. METHODS: The authors reviewed the clinicopathologic features, treatment, and outcome of 13 children (7 boys and 6 girls) with diagnoses of primary extracranial MRT at St. Jude Children's Research Hospital between 1981 and 1990. RESULTS: The median age at diagnosis was 8 months (range, 10 weeks-18 years). Primary sites included the kidney (seven patients), liver (three patients), soft tissue of scapula, posterior mediastinum, and retroperitoneum. Seven patients had metastatic disease (lungs, six patients; cutaneous hemangioma, one patient). Ten patients had surgical resection of primary tumor (complete, nine patients; incomplete, one patient). Eleven patients had chemotherapy with multiple agents. Three of four chemotherapy responses observed were with regimens containing ifosfamide. Partial responses (PR, > 50% reduction in tumor size) were obtained in one patient who received single-agent ifosfamide during disease relapse (PR lasting 2 months), one patient who received a combination of ifosfamide, carboplatin, and etoposide at diagnosis (PR lasting 5 months), and one patient who was treated with bleomycin, cyclophosphamide, doxorubicin, and vincristine at diagnosis (PR lasting 5 months) and subsequently with ifosfamide in combination with carboplatin and etoposide during disease relapse (PR lasting 4 months). All patients died at a median period of 5 months (range, 0.5-30 months) after diagnosis. CONCLUSIONS: Based on this review, the authors recommend using ifosfamide alone or in combination with carboplatin and etoposide in front-line therapy for malignant rhabdoid tumor.

Adolescent↗
PubMed1993

Alveolar rhabdomyosarcoma with the t(2;13): cytogenetic findings and clinicopathologic correlations.

We describe here the clinical and pathologic features associated with a specific translocation, t(2;13), in alveolar rhabdomyosarcoma. Tumor specimens from 14 patients with a t(2;13)-positive alveolar rhabdomyosarcoma were studied for cytogenetic-clinicopathologic correlations. Three patients had occult primary tumors; nine patients had primary tumors of the trunk (mediastinal, pelvic, or rectal). The presence of the t(2;13) was ascertained from examination of tumor involved bone marrow in ten patients who had widespread metastatic disease at the time of diagnosis. Marrow involvement was so extensive in three cases that they were initially diagnosed as acute leukemia. Response to therapy was poor, with only five patients achieving a complete response. Twelve patients have died of their disease at a median survival time of 6 months from diagnosis and one is living with recurrent disease; only one patient survives free of disease.

Adolescent↗
PubMed1993

Use of HBA 71 and anti-beta 2-microglobulin to distinguish peripheral neuroepithelioma from neuroblastoma.

Peripheral neuroepithelioma (PN) can be difficult to distinguish from undifferentiated neuroblastoma (NBL) in the absence of molecular and cytogenetic studies. These primitive neural tumors of childhood are similar in morphology and immunocytochemistry, despite their distinct biochemical and behavioral characteristics. The recently developed monoclonal antibody HBA 71 is specific for the product MIC2, a marker of peripheral primitive neuroectodermal tumors. Because beta 2-microglobulin also is selectively expressed by most tumors in this subset, we examined whether a combination of the antibodies HBA 71 and anti-beta 2-microglobulin could facilitate the differentiation of the two malignancies. We histologically confirmed the diagnoses of 45 paraffin-embedded tumors of presumed neuroectodermal origin (19 PNs and 26 NBLs) from the pathology files of St Jude Children's Research Hospital. Samples were immunohistochemically stained using HBA 71 and anti-beta 2-microglobulin. Molecular and cytogenetic data were correlated with the results in a subset of eight patients. Sixteen (84%) of the 19 PNs reacted with HBA 71 and 13 (76%) of 17 PNs reacted with anti-beta 2-microglobulin. None of the NBLs reacted with either antibody. Three PNs were identified by HBA 71 alone and one was identified by anti-beta 2-microglobulin alone. Cellular genetic findings were consistent with the results. HBA 71 and anti-beta 2-microglobulin, when used in combination, can facilitate the differential diagnosis of PN and NBL.

12E7 Antigen↗
PubMed1993

Departmental audit in histopathology.

Audit is now part of any laboratory service. Histopathology is no exception, and we have set up a system which allows us to review 4% of our specimens. These specimens are identified using a random number generator and reviewed by a consultant pathologist. Both slides and wet specimens are reviewed and graded according to a set scheme. The results from the first year of operation (1990) show a high rate of accuracy with no serious diagnostic disagreements between the auditor and the reporting pathologist. However, some errors which we would wish to prevent were detected and the audit has allowed us to take corrective measures. In our opinion, this form of audit is useful and necessary to maintain good clinical practice. The cost is considerable--histopathology is by its nature labour intensive. Recognition of this fact by health boards is essential if such systems are to continue.

Biopsy↗