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Biomedical subjects

D M Parham

Publications and source records attributed to D M Parham.

At least 181 records · Page 10Linked to original sources

Nephrogenic adenoma of urinary bladder associated with malakoplakia.

A case of nephrogenic adenoma occurring in a twelve-year-old black female child, associated with recurrent Escherichia coli urinary tract infection is described. The patient was followed for over six years and treated with repeated cystoscopic examinations and fulgurations of the lesion. Five years after the initial diagnosis, malakoplakia of the bladder developed in association with nephrogenic adenoma. There was no evidence of invasion of the bladder by the lesion during these six years. Electron microscopic study of nephrogenic adenoma indicated its origin from the urothelium. Nephrogenic adenoma of the bladder is to be considered as a benign metaplastic lesion of the urothelium and is to be treated with repeated cystoscopic fulgurations.

Adenoma↗

Mandible-like structure with teeth in an ovarian cystic teratoma.

The findings of a tooth-bearing mandible-like structure within a large ovarian dermoid cyst is reported. Although the presence of assorted teeth and bone is not uncommon in teratomatous lesions, the formation of an apparent alveolar structure possessing multiple teeth is found less often.

Adult↗

Muscle edema in musculoskeletal tumors: MR imaging characteristics and clinical significance.

To determine the frequency and clinical significance of tumor-associated muscle edema, magnetic resonance (MR) imaging findings in 46 consecutive patients with benign or malignant musculoskeletal lesions were reviewed. Increased muscle signal intensity on T2-weighted, STIR (short-inversion-time inversion-recovery), and gadopentetate dimeglumine-enhanced T1-weighted images was present in 41 cases, with the clearest delineation of tumor margins seen on T2-weighted images. Typical peri/paratumoral edema (PTE) was present in equal proportions of malignant (25 of 37) and benign lesions (six of nine). Massive edema involving the entirety of at least one contiguous muscle--to the authors' knowledge, a previously undescribed finding--was identified on MR images of eight malignant and two benign lesions (22% of both groups). All cases of massive edema had a substantial soft-tissue component and involved muscles disrupted by tumor at the point of attachment to bone. Malignant tumors associated with massive edema were larger than those with typical or no PTE, showed a poorer response to initial chemotherapy, and had a higher frequency of metastases at diagnosis. Thus, the presence of massive muscle edema appears to be an ominous clinical finding in patients with malignant musculoskeletal lesions.

Adolescent↗

Automated pixel-by-pixel mapping of dynamic contrast-enhanced MR images for evaluation of osteosarcoma response to chemotherapy: preliminary results.

An automated technique for pixel-by-pixel computer mapping of tumor necrosis was developed to improve the accuracy and applicability of dynamic contrast agent-enhanced magnetic resonance (MR) imaging in assessing the response of osteosarcoma to preoperative chemotherapy. The technique was evaluated in nine osteosarcoma patients who underwent MR imaging at diagnosis (n = 7) and after preoperative chemotherapy (n = 9). Sequential FLASH (fast low-angle shot) images of the tumor were obtained in one plane every 15 seconds before and for 3 minutes after gadopentetate dimeglumine injection. A region of interest was selected that included the entire tumor area. Slopes representing percent increase in signal intensity over baseline values per minute were calculated automatically for each pixel and displayed as gray-scale maps of the tumor. Matching histologic maps of each tumor were obtained. Visual region-by-region comparison of the pixel and histologic maps showed a high degree of correlation and the ability of the MR imaging technique to help identify small foci of residual viable tumor.

Adolescent↗

Comparison of immunohistochemistry and silver stain for the diagnosis of pediatric Helicobacter pylori infection in urease-negative gastric biopsies.

We compared immunohistochemical and silver stains of pediatric gastric biopsy sections for the identification of Helicobacter pylori infection with chronic inflammation and a negative urease screening test. Thirty-seven patients (age range 10 months to 21 years) whose gastric antral biopsies were negative for the rapid urease test (CLO(R)) but positive for lymphocytic infiltration were selected for a retrospective study. Specimens had been subjected to a rapid urease test (CLO(R)) and hematoxylin and eosin staining, and Dieterle silver staining and immunohistochemical staining specific for H. pylori were also performed. Twelve additional patients with urease-positive biopsies were used as controls. With Dieterle staining, 8/37 (22%) urease-negative biopsies contained organisms morphologically compatible with H. pylori, 21/37 (56%) contained organisms not compatible with H. pylori, and 8/37 (22%) were negative for organisms. Immunostaining confirmed 6/8 (75%) Dieterle-positive cases as being H. pylori, was negative in 2/8 (25%) Dieterle-positive cases, and was positive in 2/8 (25%) Dieterle-negative cases. Biopsies from 8/12 (67%) urease-positive specimens contained organisms seen with both Dieterle and immunohistochemical stains, and 4/12 (33%) were negative with both stains. Although both stains yielded comparable results with H. pylori-positive biopsies, Dieterle staining was potentially confusing because of nonspecific staining of other organisms. A significant proportion of (CLO(R))-negative biopsies was positive for H. pylori with special stains. We therefore recommend the use of immunohistochemical staining rather than silver staining in the evaluation of urease-negative gastric biopsies demonstrating chronic inflammation in children.

Adolescent↗

The frozen section yesterday and today: pediatric solid tumors--crucial issues.

This article is the offshoot of a Pediatric Oncology Group (POG) seminar presented at the Adams Mark Hotel, Denver, Colorado, Friday, May 21, 1999, titled "The Frozen Section in Pediatric Solid Tumors--Crucial Issues." There were eight presenters who spoke on a wide range of topics that included historical perspectives of the frozen section and discussion of the following systems: brain, renal, germ cell, bone, soft tissue, and lymph nodes. To complement these presentations, a pediatric surgeon explained his concern and philosophy regarding the use of frozen sections, and a lawyer tackled the issues and risks in rendering a frozen section diagnosis. We think that this review covers all the important aspects of the frozen section in our current practice of pediatric pathology.

Child, Preschool↗

Detection of mycobacterial infections using the Dieterle stain.

Retrospective review comparing the modified Dieterle stain with standard acid-fast stains was performed on seven surgical pathology cases that contained culture-positive mycobacteria infections. Tissues examined comprised cervical and submandibular lymph nodes and soft tissues of the face and chest. Modified Dieterle staining was performed on paraffin-embedded tissue sections, and the results were compared with those of hematoxylineosin stains and auramine-rhodamines and carbolfuchsin acid-fast stains. The acid-fast stain showed organisms in three of seven cases on initial review and five of seven cases on retrospective review; the auramine-rhodamine stain retrospectively revealed organisms in five cases. In contrast, the Dieterle stain showed organisms in all seven sections on retrospective examination. Dieterle stains revealed either beaded bacilli or nocardia-like filamentous organisms, sometimes with abundant granular debris possibly representing degenerative organisms. In three cases in which bacteria were readily apparent with the Dieterle stain, only rare organisms could be identified with the acid-fast stain. The modified Dieterle stain was more sensitive than the acid-fast stain in the identification of mycobacteria in pediatric specimens, and its use is recommended in cases with necrotizing granulomas. However, its specificity is limited by morphologic similarities of the organisms to those of nocardiosis and cat scratch disease.

Adolescent↗

Enzyme-linked immunoassay for respiratory syncytial virus is not predictive of bronchiolitis in sudden infant death syndrome.

Although respiratory syncytial virus (RSV)-infected infants may present with apnea, the role that RSV plays in sudden infant death syndrome (SIDS) is speculative. To determine whether RSV is associated with bronchiolitis in these patients, we examined histologic sections of lungs from 41 apparent SIDS cases and compared the results with those of enzyme-linked immunofluorescent assay (EIA) from nasal washings. Bronchiolitis was defined by a bronchiolar inflammatory cell infiltrate plus epithelial necrosis. A positive EIA was associated with bronchiolitis in 8 instances, compared with 6 having a positive EIA and negative histology, 14 having a negative EIA and positive histology, and 13 having EIA and histology both negative. These results yield a predictive value of a positive test of 57% and a predictive value of a negative test of 48% (P > .9 by chi square analysis). Although RSV of the upper respiratory tract may be related to SIDS, our results indicate that EIA of nasal washings is not predictive of bronchiolitis, and we recommend other means of verification of histologic results.

Antibodies, Viral↗

Intergroup Rhabdomyosarcoma Study: update for pathologists.

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma of childhood, and 75% of such cases in the United States are reviewed at the Pathology Center for the Intergroup Rhabdomyosarcoma Study Group (IRSG). The first four generations of IRSG therapeutic trials (IRS I-IV) and supportive pathologic studies have generated a new International Classification of Rhabdomyosarcoma (ICR) that offers new morphologic concepts to the practicing pathologist. The objective of this report is to clearly define emerging histopathologic categories of RMS as defined by the ICR, and to emphasize correlative immunohistochemical or molecular studies. Emerging ICR variants of RMS place the patient in widely divergent prognostic categories (superior, botryoid or spindle cell variants; poor, solid alveolar or diffusely anaplastic variants). The cardinal histopathologic features of the ICR combined with results of studies of fusion genes seen with t(1;13) and t(2;13) will help delineate therapeutic subgroups of RMS for the fifth generation (IRS V) of IRSG studies. Consequently, it is imperative for the practicing pathologist to be familiar with the practical workup and diagnosis of RMS in childhood.

Biomarkers, Tumor↗

Peripheral neuroepithelioma with ganglion cells: report of two cases and review of the literature.

Peripheral neuroepitheliomas, also known as peripheral primitive neuroectodermal tumors, are by definition primitive embryonal lesions generally composed of poorly differentiated neuroectodermal elements. We have examined two cases that paradoxically contain extensive foci of ganglionic differentiation similar to that of ganglioneuroblastoma, in addition to primitive elements. One tumor arose from the chest wall of an 8-year-old male and the other from the abdominal wall of a 15-year-old male. Differentiation into a mature ganglionic phenotype was confirmed by immunohistochemistry in one case. Rare peripheral neuroepitheliomas have a capacity for maturation that is not generally appreciated. These lesions should not be confused with ganglioneuroblastomas, which are genotypically unrelated neoplasms.

Adolescent↗

Malignant peripheral nerve sheath tumor of bone in children and adolescents.

Malignant peripheral nerve sheath tumor (MPNST) of bone is a rare entity. We have examined three lesions that fit standard histopathologic criteria for MPNST of soft tissues but that arose in the skeleton of three children aged 6 to 13 years. None was affected by neurofibromatosis 1 (NF1). Histologic features typical of MPNST included spindle cells with comma-shaped nuclei, tactoid bodies, nuclear palisading, hyaline bands, and schwannoma-like and curlicue foci. Epithelioid foci were seen in two cases, and heterologous differentiation in one. Immunohistochemistry revealed positivity for S-100 (1 positive/3 tested), vimentin (3/3), glial fibrillary acidic protein (2/3), CD34 (1/1), and CD68 (1/2). Studies for CD99 (0/3), epithelial membrane antigen (0/3), cytokeratin (0/3), CD57 (0/3), and HMB-45 (0/2) were negative. Ultrastructural findings in one of two cases examined included interlacing, attenuated cytoplasmic processes, microtubules, and rare dense-core granules. We conclude that MPNST may arise as a primary bone neoplasm in children without NF1.

Adolescent↗

Clinicopathologic study of ectomesenchymomas from Intergroup Rhabdomyosarcoma Study Groups III and IV.

Ectomesenchymomas (EM) are rare malignant neoplasms usually consisting of rhabdomyosarcoma (RMS) with a neural component. Only 21 cases have been previously reported. Here we extend the clinicopathologic spectrum of EM by describing our findings in 15 cases. Only 5 patients were infants; 10 were < or =3 years old and 5 were > or =6 years old. No male predilection was observed; 7 were female. The originating institutional diagnoses were; RMS (12), undifferentiated sarcoma (1), or EM (2), suggesting underdiagnosis of this entity. The primary tumor sites included external genital (5), pelvis/abdomen (6), head and neck (3), and extremity (1). The size of the primary neoplasm was usually > or =5 cm at diagnosis but dissemination only occurred in a minority. Local infiltration was not uncommon. These neoplasms were typically multilobate, thinly encapsulated, hemorrhagic, and necrotic. Light microscopic features were highly variable, but embryonal RMS with scattered or clustered ganglion cells, often in lacunae, was characteristic. In some cases, primitive neuroblastic or neuroectodermal areas were found and/or a component of alveolar RMS was seen. Focal anaplasia was occasionally observed. Mitotic activity appears higher than previously appreciated and some necrosis was invariably present. Electron microscopy was performed in 11 cases, which confirmed skeletal muscle +/- neural differentiation. Cytogenetic studies performed in five cases revealed no specific abnormality. Monoclonal neuron-specific enolase was the best marker of ganglion cells and primitive neural elements. MIC-2 (CD99) membrane expression was not definitively present in any of the six cases examined. A number of the above parameters appear to be of some prognostic significance, but overall, these neoplasms appear to have a similar outcome as would be predicted for their RMS element alone (exclusive of any neural component), with respect to the RMS subtype, age of the patient, and anatomic location of the neoplasm.

Abdominal Neoplasms↗

Treatment of children with peripheral primitive neuroectodermal tumor or extraosseous Ewing's tumor with Ewing's-directed therapy.

PURPOSE: We report the treatment and outcome of patients with peripheral primitive neuroectodermal tumor (PNET) and extraosseous Ewing's tumor (EOE) using Ewing's-directed therapy, including an ifosfamide and etoposide window. METHODS: Seventeen pediatric patients with peripheral PNET (n = 14) or EOE (n = 3) were enrolled between 1988 and 1992 on our institutional Ewing's protocol. Induction therapy comprised a 9-week "window" of ifosfamide and etoposide, followed by 9 weeks of therapy with cyclophosphamide and Adriamycin (Adria Laboratories, Columbus, OH). Response assessment after 17 weeks was followed by surgery and/or radiotherapy (doses based on tumor size and response to induction), repeat evaluation, and maintenance chemotherapy with alternating courses of vincristine/dactinomycin, ifosfamide/etoposide, and cyclophosphamide/Adriamycin for a total of 45 weeks. RESULTS: At diagnosis, 8 patients had large lesions (>8 cm) and 3 had pulmonary metastases (1 with large tumor). Surgical resection was performed at diagnosis for 9 patients and after induction therapy for 5. During window therapy, all of the 9 evaluable patients responded (8 partial, I objective), and no patient without measurable disease developed disease progression. Responses were maintained or improved during subsequent induction in six of the patients with residual disease. Fourteen patients received local radiotherapy. At 49 to 94 months after diagnosis, 12 patients are disease-free (1 in second remission), 4 have died, and 1 is alive with disease. The five-year overall and progression-free survival rates are 77 +/- 13% and 62 +/- 16%, respectively. CONCLUSION: The use of consistent Ewing's-directed combined-modality therapy for patients with soft tissue peripheral PNET/EOE results in survival similar to that of patients with osseous Ewing's tumor. The combination of ifosfamide and etoposide appears active and should be incorporated in future treatment protocols.

Adolescent↗

Myofibrosarcoma of the head and neck in children.

We have identified a distinctive malignant soft tissue neoplasm that occurred in the head and neck region of six children. Histologically, these neoplasms presented an array of features ranging from low-grade spindle cell to high-grade fibrohistiocytic histologies and often had myoid characteristics. Ultrastructural and immunohistochemical studies indicated that they contained neoplastic myofibroblasts that were variably positive for vimentin (4 positive/4 tested), alpha-smooth muscle actin (4/5), muscle-specific actin (5/5), desmin (2/5), and v-src protein substrate p80/85 (4/5). Three patients died of rapidly progressive unresectable local disease, one died of metastatic and local disease, and two are alive 13 months and 8 years after wide resection. We conclude that these neoplasms form a distinctive subset of pediatric soft tissue sarcomas that display an aggressive clinical behavior, typically with local recurrence, and exhibit features of myofibroblastic differentiation.

Adolescent↗

Presarcomatous lesions of experimentally induced sarcomas in rats: morphologic, histochemical, and immunohistochemical features.

Morphological studies have been performed mainly on manifest sarcomas, leading to divergent views of its histogenesis. However, histogenesis requires understanding of the tumor precursor cells and cannot be resolved by static morphologic studies. Defining presarcomatous lesions is made more difficult because they do not possess a basement membrane that serves as biologic and nosologic boundary like in epithelial cancers. The present study, therefore, investigated the early phases of experimentally induced rat sarcoma, which closely resembles human malignant fibrous histiocytoma (MFH). Histological, enzyme- and immunohistochemical methods were used to define the sequential events involved in tumorigenesis. A benzo[a]pyrene-oil mixture was injected intramuscularly into the thighs of rats, producing MFH 120 days later. Groups of animals were sacrificed every 10 days. The injections produced soft tissue lesions characterized by three distinct phases that overlapped or existed simultaneously in one animal: an initial acute inflammatory reaction characterized by an infiltration of lymphocytes, monocytes and macrophages, a second mesenchymal fibromatous phase characterized by the predominance of spindle-shaped, focally atypical fibroblast-like cells and collagen, and a third premalignant neovascularization phase characterized by dominant capillary proliferations. Overt MFH developed 120 days after injection and consisted of spindle-shaped fibroblast- and histiocyte-like cells containing atypical mitoses and arranged in a storiform pattern. Control animals injected with olive oil revealed acute inflammatory reactions after 30 days and no signs of chronic inflammation or malignancy after 60 and 120 days. We concluded that these experimentally-induced rat sarcomas develop in a triphasic pattern that resembles non-healing granulation tissue, with neovascularization preceding the occurrence of overt MFH.

Animals↗

Primary malignant rhabdoid tumor of the brain: clinical, imaging, and pathologic findings.

PURPOSE: To describe the imaging and pathologic findings of malignant rhabdoid tumor (MRT), a rare primary brain neoplasm affecting children. METHODS: The CT and/or MR features, pathologic findings, and clinical records of three children with primary MRT of the brain were retrospectively reviewed. RESULTS: The tumors, large, left-sided cerebral masses, were intraventricular in two cases. MR images in one patient showed T1- and T2-weighted signal intensity isointense with gray matter. Multiple necrotic/cystic foci were present in all cases, with two showing a patchy pattern of enhancement on CT and MR. The diagnosis of MRT was documented by ultrastructural and immunohistochemical studies. All patients had normal abdominal CT scans, excluding the possibility of primary renal rhabdoid tumor metastatic to the brain. The disease progressed rapidly in each case, despite surgery, chemotherapy, and craniospinal irradiation, with serial imaging evidence of tumor regrowth at the primary site and the development of metastatic satellite lesions. CONCLUSIONS: The diagnosis of primary MRT of the brain can be made only pathologically; however, the nonspecific imaging findings in these cases suggest that MRT should be considered in the differential diagnosis of large childhood intracranial neoplasms.

Adult↗