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L P Dehner

Publications and source records attributed to L P Dehner.

At least 19 recordsLinked to original sources
PubMed2007

Genomic aberrations are rare in urothelial neoplasms of patients 19 years or younger.

Urothelial neoplasms in patients 19 years of age or younger are rare, and the data regarding clinical outcome are conflicting. Molecular data are not available. Urothelial tumours from 14 patients aged 4 to 19 years were analysed, including FGFR3 and TP53 mutation screening, comparative genomic hybridization (CGH), UroVysion FISH analysis, polymerase chain reaction for human papillomavirus (HPV), microsatellite analysis using the NIH consensus panel for detection of microsatellite instability (MSI) and six markers for loss of heterozygosity on chromosome arms 9p, 9q, and 17p and immunohistochemistry for TP53, Ki-67, CK20 and the mismatch repair proteins (MRPs) hMSH2, hMLH1, and hMSH6. Based on the 2004 WHO classification, one urothelial papilloma, seven papillary urothelial neoplasms of low malignant potential (PUNLMPs), five low-grade, and one high-grade papillary urothelial carcinoma were included. No multifocal tumours were found and recurrence was seen in only one patient with a urothelial papilloma. All patients were alive with no evidence of disease at a median follow-up of 3.0 years. We found no mutations in FGFR3, deletions of chromosome arms 9p, 9q or 17p, MSI or MRP loss, or HPV positivity in any of the patients. Three cases showed chromosome alterations in CGH analyses, urothelial dedifferentiation with CK20 overexpression, or aneuploidy, and one TP53 mutation with TP53 overexpression was found. Urothelial neoplasms in people younger than 20 years are predominantly low grade and are associated with a favourable clinical outcome. Genetic alterations frequently seen in older adults are extremely rare in young patients. Urothelial neoplasms in children and young adults appear to be biologically distinct and lack genetic instability in most cases.

Adolescent↗
PubMed2004

Lipofibromatosis presenting as a pediatric neck mass.

Lipofibromatosis is a recently described, benign neoplasm that presents in the pediatric population [J.F. Fetsch, M. Miettinen, W.B. Laskin, M. Michal, F.M. Enzinger, A clinicopathologic study of 45 pediatric soft tissue tumors with an admixture of adipose tissue and fibroblastic elements, and a proposal for classification as lipofibromatosis, Am. J. Surg. Pathol. 24 (2000) 1491-1500]. It is a rare soft tissue tumor histologically distinct from other fibromatoses such as juvenile fibromatosis, fibrous hamartoma of infancy, calcifying aponeurotic fibroma, and lipoblastoma. Distinguishing histopathologic features of lipofibromatosis include abundant and disorganized adipose lobules traversed by bundles of spindled fibroblast-like cells. It most commonly presents in the extremities. We present a case involving a young girl, which we believe represents the first report of lipofibromatosis involving the neck.

Child↗
PubMed2001

A role for fluorescence in situ hybridization detection of chromosome 22q dosage in distinguishing atypical teratoid/rhabdoid tumors from medulloblastoma/central primitive neuroectodermal tumors.

It has been postulated that infants with medulloblastomas/central primitive neuroectodermal tumors (MB/PNET) may fare worse than older patients because some of them harbor unrecognized atypical teratoid/rhabdoid tumors (AT/RT), rare intracranial neoplasms that are typically unresponsive to therapy and rapidly fatal. Although small primitive cells are common to both entities, chromosome 22q11.2 deletions are common only in AT/RTs. Using fluorescence in situ hybridization (FISH) on archival, paraffin-embedded biopsy tissue with commercially available probes to 22q11.2, the region associated with RTs, we studied 8 cases of AT/RT, 12 cases of MB/PNET, and 4 cases of primitive central nervous system (CNS) neoplasms, which were difficult to classify. 22q Deletions were identified in 6 of 8 (75%) conventional AT/RTs and 0 of 12 (0%) children with classic MB/PNET. Of the 4 originally "difficult to classify" cases, 3 had deletions of 22q. In light of the FISH results, review of the morphology and immunophenotype resulted in 3 tumors being reclassified as AT/RTs and 1 as a large cell MB. These 4 cases highlight the potential diagnostic use of FISH for selected cases of primitive CNS malignancies in children and substantiate the notion that misdiagnosed AT/RTs may, in part account for the worse prognosis associated with "MB/PNET" in children younger than 2 years of age.

Adolescent↗
PubMed2001

Visceral primitive peripheral neuroectodermal tumors: a clinicopathologic and molecular study.

Ewing sarcoma-primitive neuroectodermal tumor (EWS/PNET) belongs to the group of pediatric small round blue cell tumors; although EWS/PNET is classically a tumor of the soft tissue or bone in children and young adults, individual cases have been described in patients of all ages. A group of chromosomal translocations involving the EWS gene and a member of the Ets transcription factor family of genes has been detected in EWS/PNET, and heterogeneity in the precise breakpoint of the translocation has been shown to generate a group of related fusion transcripts that may have prognostic significance. Within the last decade, the clinicopathologic spectrum of EWS/PNET has been markedly expanded by recognition that the tumor may also have a visceral origin. To determine whether visceral EWS/PNET has the same pattern of genetic alterations and range of fusion transcripts as EWS/PNET of bone and soft tissue, we performed reverse-transcription polymerase chain reaction-based testing of formalin-fixed, paraffin-embedded tissue from a series of visceral tumors for which the diagnosis of EWS/PNET was well established. Together with additional cases compiled from the literature, EWS-Fli1 (or a related fusion transcript) was present in 18 of 19 visceral EWS/PNET, with a distribution of transcript types not statistically different from EWS/PNET of soft tissue and bone (P >.05, chi(2) test). These results firmly establish the genetic relationship between EWS/PNET of visceral sites, soft tissue, and bone.

Abdominal Neoplasms↗
PubMed2001

Chromosome 22q dosage in composite extrarenal rhabdoid tumors: clonal evolution or a phenotypic mimic?

Composite extrarenal rhabdoid tumors (CERTs) represent a diverse group of neoplasms with rhabdoid shape in combination with one of several distinctive tumor types. Like the classic renal and extrarenal malignant rhabdoid tumor (MRT), as well as the atypical teratoid/rhabdoid tumor (AT/RT) of the central nervous system, CERTs typically show aggressive clinical behavior. Deletions and mutations of the INII gene on 22q11.2 have been identified in most classic MRTs and AT/RTs; however, it is not known whether the rhabdoid components in CERTs have similar genetic abnormalities. Using fluorescence in situ hybridization (FISH) on archival, paraffin-embedded tissue with a commercially available probe in close proximity to the INII locus (bcr), as well as other chromosome 22 probes, we studied 4 cases of MRT, 13 of AT/RT, and 16 of CERT (3 melanoma, 4 meningioma, 7 carcinoma, 1 rhabdomyosarcoma, and 1 neuroblastoma). Deletion of the 22q11.2 locus was demonstrated in 10 (77%) of 13 AT/RTs and 3 (75%) of 4 MRT, including 1 congenital MRT. Of the 16 CERTs, only 2 (a rhabdoid meningioma and a carcinoma with rhabdoid features; 13%) harbored a deletion at this locus. This difference was statistically significant (P <.001). We conclude that deletion of 22q11.2, typical of most classic MRTs and AT/RTs, is infrequently seen in CERTs. This suggests that the rhabdoid component of CERTs does not evolve by way of the genetic alteration characteristic of MRTs or AT/RTs, but represents instead a distinct phenotype shared by a number of tumors as they undergo anaplastic progression.

Adolescent↗
PubMed2001

Anaplastic lymphoma kinase (ALK) expression in the inflammatory myofibroblastic tumor: a comparative immunohistochemical study.

Inflammatory myofibroblastic tumor (IMT) is an uncommon mesenchymal neoplasm with a variable histologic appearance that may mimic other spindle cell processes, particularly nodular fasciitis, desmoid tumor, and in intra-abdominal locations, gastrointestinal stromal tumor. Recently, gene fusions involving ALK at chromosome 2p23 have been described in IMTs. The resultant ALK protein overexpression in the myofibroblastic component of these tumors is detectable by immunohistochemistry. We examined 73 IMTs, 20 cases of nodular fasciitis, 15 desmoid fibromatoses, and 15 gastrointestinal stromal tumors by immunohistochemistry using ALK-11, a rabbit polyclonal antibody that recognizes the C-terminus of the protein. ALK positivity was detected in 44 of 73 (60%) IMTs. All cases of nodular fasciitis, desmoid fibromatosis, and gastrointestinal stromal tumors were ALK negative (p < 0.001). These findings demonstrate that ALK positivity is common in IMTs, and immunohistochemistry using anti-ALK antibodies can be helpful in the differential diagnosis of these neoplasms. In addition, anti-ALK staining seems to correlate with those IMTs that have the typical tri-patterned histologic appearance and clinical presentation, providing additional support to the premise that IMT is a distinctive clinicopathologic entity within the broad category of inflammatory pseudotumors.

Adolescent↗
PubMed2000

Fine-needle aspiration cytology of mesenchymal hamartoma of the chest wall.

We report on an uncommon entity, the so-called "chest wall chondromatous hamartoma" or "mesenchymal hamartoma of the chest wall" (MHCW), diagnosed by fine-needle aspiration (FNA) cytology in a 6-mo-old boy. Radiologic features were those of an aggressive lesion with rib expansion and destruction, that contrasted with aspirate smears showing bland cartilage and spindled mesenchymal elements. The clinicoradiographic features together with the FNA yield of mixed cellular elements aided in the correct diagnosis of MHCW.

Biopsy, Needle↗
PubMed2000

The enigmatic inflammatory pseudotumours: the current state of our understanding, or misunderstanding.

The inflammatory pseudotumour is a bona fide tumour in the sense of a mass lesion, which is known to present in virtually every anatomic region and organ from the central nervous system to the gastrointestinal tract. A fundamental question about pathogenesis is whether the inflammatory pseudotumour is a pseudo-or true neoplasm. There is evidence to support the argument that some of these fibroinflammatory masses are infection-associated and are often characterized by a proliferation of spindled histiocytes and/or dendritic cells, in contrast to a myofibroblastic proliferation in the other inflammatory pseudotumour, also known as the inflammatory myofibroblastic tumour.

Bacterial Infections↗
PubMed2000

Gliomatosis peritonei as a complication of a ventriculoperitoneal shunt: case report and review of the literature.

Gliomatosis peritonei, the implantation of neuroglial tissue upon the peritoneal surfaces, is a rare event most often associated with solid or immature teratomas of the ovary in young girls. The authors report a case of a 10-month-old girl with a ventriculoperitoneal shunt (VPS) who presented with bilateral inguinal hernias. Herniorrhaphy was uneventful. Microscopic examination of the hernia sacs showed exuberant mesothelial hyperplasia containing multiple nests of differentiated glial tissue. Subsequent computed tomography and laparoscopy disclosed normal ovaries with no evidence of intraabdominal or pelvic abnormalities. Gliomatosis peritonei in this case was attributed to transport of glial tissue from the cerebrospinal fluid into the peritoneal cavity via the shunt. With the exclusion of an ovarian germ cell neoplasm and in the presence of a VPS, the clinical course with regard to the glial implants in these children is uneventful. If it is appreciated that gliomatosis peritonei may be a complication of a VPS, an extensive clinical evaluation generally is unnecessary.

Choristoma↗
PubMed2000

Malignant peripheral nerve sheath tumors with t(X;18). A pathologic and molecular genetic study.

Spindle cell sarcomas often present the surgical pathologist with a considerable diagnostic challenge. Malignant peripheral nerve sheath tumor, leiomyosarcoma, fibrosarcoma, and monophasic synovial sarcoma may all appear similar histologically. The application of ancillary diagnostic modalities, such as immunohistochemistry and electron microscopy, may be helpful in the differentiation of these tumors, but in cases in which these adjunctive techniques fail to demonstrate any more definitive evidence of differentiation, tumor categorization may remain difficult. Cytogenetic and molecular genetic characterization of tumors have provided the basis for the application of molecular assays as the newest components of the diagnostic armamentarium. Because the chromosomal translocation t(X;18) has been observed repeatedly in many synovial sarcomas, it has been heralded as a diagnostic hallmark of synovial sarcoma. To formally test the specificity of this translocation for the diagnosis of synovial sarcoma, RNA extracted from formalin-fixed, paraffin-embedded tissue from a variety of soft tissue and spindle cell tumors was evaluated for the presence of t(X;18) by reverse transcriptase-polymerase chain reaction. Although 85% of the synovial sarcomas studied demonstrated t(X;18), 75% of the malignant peripheral nerve sheath tumors in our cohort also demonstrated this translocation. We conclude that the translocation t(X;18) is not specific to synovial sarcoma and discuss the implications of the demonstration of t(X;18) in a majority of malignant peripheral nerve sheath tumors.

Adolescent↗
PubMed2000

Malignant peripheral nerve sheath tumors with t(X;18). A pathologic and molecular genetic study.

Spindle cell sarcomas often present the surgical pathologist with a considerable diagnostic challenge. Malignant peripheral nerve sheath tumor, leiomyosarcoma, fibrosarcoma, and monophasic synovial sarcoma may all appear similar histologically. The application of ancillary diagnostic modalities, such as immunohistochemistry and electron microscopy, may be helpful in the differentiation of these tumors, but in cases in which these adjunctive techniques fail to demonstrate any more definitive evidence of differentiation, tumor categorization may remain difficult. Cytogenetic and molecular genetic characterization of tumors have provided the basis for the application of molecular assays as the newest components of the diagnostic armamentarium. Because the chromosomal translocation t(X;18) has been observed repeatedly in many synovial sarcomas, it has been heralded as a diagnostic hallmark of synovial sarcoma. To formally test the specificity of this translocation for the diagnosis of synovial sarcoma, RNA extracted from formalin-fixed, paraffin-embedded tissue from a variety of soft tissue and spindle cell tumors was evaluated for the presence of t(X;18) by reverse transcriptase-polymerase chain reaction. Although 85% of the synovial sarcomas studied demonstrated t(X;18), 75% of the malignant peripheral nerve sheath tumors in our cohort also demonstrated this translocation. We conclude that the translocation t(X;18) is not specific to synovial sarcoma and discuss the implications of the demonstration of t(X;18) in a majority of malignant peripheral nerve sheath tumors.

Adolescent↗
PubMed2000

Diagnostic gold standard for soft tissue tumours: morphology or molecular genetics?

The recognition of recurrent genetic alterations in specific tumour types has provided the basis for the reclassification of certain soft tissue neoplasms, and molecular analysis of patient material has the potential to provide both diagnostic and prognostic information. In this review, we evaluate the role of molecular genetic testing as the prospective 'gold standard' for sarcoma diagnosis. Molecular genetic testing, as with every new method, promises to improve accuracy and to be more sensitive and less subjective, claims that have been made previously by histochemistry, electron microscopy and immunohistochemistry. Technical limitations in molecular assays, as well as more general specificity issues, decrease the clinical usefulness of molecular pathological testing significantly and suggest that, at present, molecular evaluation is best considered an ancillary technique that neither supersedes other ancillary techniques nor eclipses traditional pathological examination.

Adult↗
PubMed2000

WT1 staining reliably differentiates desmoplastic small round cell tumor from Ewing sarcoma/primitive neuroectodermal tumor. An immunohistochemical and molecular diagnostic study.

Differentiating desmoplastic small round cell tumor (DSRCT) from another similar small round cell tumor of childhood, the Ewing sarcoma/primitive neuroectodermal tumor (EWS/PNET), can be difficult because morphologic and immunohistochemical features overlap. We studied the predictive value of immunohistochemistry with an antibody to the C-terminal region of the Wilms tumor (WT1) protein for differentiating DSRCT from EWS/PNET in 24 malignant small round cell tumors that had been previously diagnosed as DSRCT or EWS/PNET by standard methods. We performed reverse transcriptase-polymerase chain reaction (RT-PCR) analysis in cases with available tissue as a confirmatory measure: 6 of 13 DSRCTs were informative by RT-PCR, and 6 of 6 showed an EWS-WT1 fusion; all 13 DSRCTs showed strong, definitive nuclear staining with the WT1 antibody. All 11 EWS/PNETs were WT1 antibody negative; 7 of 11 cases classified as EWS/PNET were informative by RT-PCR, and 7 of 7 showed an EWS-FLI-1 fusion. For cases in which the morphologic and immunohistochemical features are consistent with a diagnosis of DSRCT, WT1 antibody staining predicts the EWS-WT1 translocation with high sensitivity and specificity and is, therefore, useful for differentiating DSRCT from EWS/PNET when genetic information is unavailable.

Abdominal Neoplasms↗
PubMed2000

Meningioma presenting as an intraoral mass in a patient with neurofibromatosis type 1.

A 77-year-old woman with neurofibromatosis type 1 presented with ill-fitting dentures due to intraoral extension of a right temporal fossa mass. Computed tomographic scanning demonstrated that the masticator space mass bowed the zygomatic arch and remodeled the lateral orbit and maxillary sinus walls, findings that were consistent with the clinical diagnosis of a neurofibroma with possible malignant transformation. However, light microscopic, immunohistochemical, and ultrastructural examination of tissue from an incisional biopsy specimen were diagnostic of meningioma. This case illustrates that the clinicopathologic differential diagnosis of an enlarging mass in patient with neurofibromatosis should include sporadic, unrelated neoplasms as well as tumors known to be associated with the syndrome.

Aged↗
PubMed1999

Terminology and morphologic criteria of neuroblastic tumors: recommendations by the International Neuroblastoma Pathology Committee.

BACKGROUND: As part of the international cooperative effort to develop a complete set of International Neuroblastoma Risk Groups, the International Neuroblastoma Pathology Committee (INPC) initiated activities in 1994 to devise a morphologic classification of neuroblastic tumors (NTs; neuroblastoma, ganglioneuroblastoma, and ganglioneuroma). METHODS: Six member pathologists (H.S., I.M.A., L.P.D., J.H., V.V.J., and B.R.) discussed and defined morphologically based classifications (Shimada classification; risk group and modified risk group proposed by Joshi et al.) on the basis of a review of 227 cases, using various pathologic characteristics of the NTs. The classification-grading system was evaluated for prognostic significance and biologic relevance. RESULTS: The INPC has adopted a prognostic system modeled on one proposed by Shimada et al. It is an age-linked classification dependent on the differentiation grade of the neuroblasts, their cellular turnover index, and the presence or absence of Schwannian stromal development. Based on morphologic criteria defined in this article, NTs were classified into four categories and their subtypes: 1) neuroblastoma (Schwannian stroma-poor), undifferentiated, poorly differentiated, and differentiating; 2) ganglioneuroblastoma, intermixed (Schwannian stroma-rich); 3) ganglioneuroma (Schwannian stroma-dominant), maturing and mature; and 4) ganglioneuroblastoma, nodular (composite Schwannian stroma-richlstroma-dominant and stroma-poor). Specific features, such as the mitosis-karyorrhexis index, the mitotic rate, and calcification, were also included to allow the prognostic significance of the classification to be tested. Recommendations are made regarding the surgical materials to use for an optimal pathobiologic assessment and the practical handling of samples. CONCLUSIONS: The current article covers the essentials and important points regarding the histopathologic evaluation of NTs. Using the morphologic criteria described herein, the INPC is proposing the International Neuroblastoma Pathology Classification. It is reported in a companion article in this issue (Cancer 1999;86:363-71).

Biometry↗
PubMed1999

The International Neuroblastoma Pathology Classification (the Shimada system).

BACKGROUND: The International Neuroblastoma Pathology Committee, which is comprised of six member pathologists, was convened with the objective of proposing a prognostically significant and biologically relevant classification based on morphologic features of neuroblastic tumors (NTs) (i.e., neuroblastoma, ganglioneuroblastoma, and ganglioneuroma). METHODS: A total of 227 cases were reviewed. Consensus diagnoses from morphologic features (criteria described separately) based on five of six or six of six agreements by the reviewer pathologists were used for prognostic analysis. Prognostic effects of morphology, both individual and in combination, taken in conjunction with age (Shimada classification, histologic grade, and risk group), were analyzed. RESULTS: Approximately 99% of cases (224 of 227) had consensus diagnoses for categorization: neuroblastoma (Schwannian stroma-poor), 190 cases; ganglioneuroblastoma, intermixed (Schwannian stroma-rich), 5 cases; ganglioneuroma (Schwannian stroma-dominant) maturing, 1 case; ganglioneuroblastoma, nodular (composite Schwannian stroma-rich/stroma-dominant and stroma-poor), 19 cases; and NT-unclassifiable, 9 cases. For the NTs, subtype (93% consensus: undifferentiated, 6 cases; poorly differentiated, 155 cases; and differentiated, 15 cases), mitosis-karyorrhexis index (90% consensus: low, 94 cases; intermediate, 40 cases; and high, 37 cases), mitotic rate (75% consensus: low, 89 cases; high, 50 cases; and not determined, 4 cases), and calcification (100% consensus: yes, 110 cases and no, 80 cases) were recorded. Statistical analysis demonstrated that the Shimada classification system (90% consensus; 3-year event free survival: 85% for the group with favorable histology and 41% for the group with unfavorable histology; P = 0.31 x 10(-9)) had a significantly stronger prognostic effect than individual features and other combinations. CONCLUSIONS: The International Neuroblastoma Pathology Classification, a system based on a framework of the Shimada classification with minor modifications, is proposed for international use in assessing NTs.

Brain Neoplasms↗
PubMed1999

Pleuropulmonary blastoma in an adult: an initial case report.

BACKGROUND: Pleuropulmonary blastoma (PPB) is a unique dysontogenetic neoplasm of childhood. Its primitive, sarcomatous features are analogous to those of other dysembryonic or dysontogenetic tumors, such as Wilms tumor, hepatoblastoma, neuroblastoma, and embryonal rhabdomyosarcoma. PPB typically presents in young children, most younger than 5 years, as a pulmonary and/or pleural-based tumor with cystic, solid, or combined cystic and solid features. These neoplasms are characterized histologically by primitive mesenchymal or a mixture of primitive and sarcomatous components and generally have an unfavorable clinical outcome: death occurs within 1-2 years after diagnosis. METHODS: Clinicopathologic and radiographic findings of a man age 36 years with a cystic and solid mass in the left hemithorax were reviewed and compared with previously studied cases of PPB. RESULTS: Pathologic examination of the mass revealed a cystic and solid neoplasm composed of malignant mesenchymal cells that were immunoreactive for vimentin and muscle specific actin and focally for desmin. The architectural and cytologic appearances as well as the immunohistochemical profile were those of type II PPB. CONCLUSIONS: To the authors' knowledge, all previously reported cases of PPB occurred in children age 12 years or younger. They believe that this case represents the first occurrence of PPB in an adult and documents the finding that, although it is uncommon, adults can develop primitive neoplasms that are usually associated with the pediatric population. In addition, the clinicopathologic features observed in the authors' adult patient were consistent with their experience with this tumor type in children. The patient died less than 1 year after diagnosis.

Adult↗