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L P Dehner

Publications and source records attributed to L P Dehner.

At least 19 recordsLinked to original sources
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↗
PubMed1999

Molecular analysis of malignant triton tumors.

Triton tumors are rare variants of malignant peripheral nerve sheath tumor (MPNST) with muscle differentiation, often seen in patients with neurofibromatosis 1 (NF1). Individuals affected with NF1 harbor mutations in the NF1 tumor suppressor gene and develop neurofibromas and MPNSTs. The NF1 gene is expressed in Schwann cells and its expression is lost in schwannian neoplasms, suggesting a role in malignant development. Separately, there is evidence that p53 suppressor gene mutations are involved in MPNSTs. To determine the role of the NF1 and p53 genes in the development of the malignant Triton tumor we examined 2 such tumors, 1 from a 3-year-old boy without clinical manifestations of NF1 and another from a 24-year-old man with NF1. Histological analysis of these tumors showed both neural and muscle differentiation with S-100 and desmin immunoreactivity, respectively. Reverse transcribed RNA polymerase chain reaction (RT-PCR) of NF1 mRNA showed NF1 expression in the sporadic tumor. Strong nuclear immunoreactivity for p53 was observed throughout the malignant population in both tumors. This was confirmed by loss of heterozygosity for p53 in the non-NF1 patient, suggesting that p53 is involved in both hereditary and sporadic Triton tumors. The finding of preserved NF1 gene expression in the non-NF1-related Triton tumor suggests that different genetic events predispose to the development of this rare neoplasm in sporadic cases.

Adult↗
PubMed1999

Cranial and extracranial fasciitis of childhood: a clinicopathologic and immunohistochemical study.

Fasciitis of various types constitutes a distinctive category of soft tissue lesions whose microscopic features are known for their potential to evoke a pathological diagnosis of one or another type of sarcoma. Nodular fasciitis is the archetype of this group of "fibrous tumors." Cranial fasciitis is considered a nonneoplastic lesion similar to nodular fasciitis, which is seen almost exclusively in infants and children and has unique clinicopathologic features. The current study documents our experience with fibrous-myofibroblastic proliferations in extracranial sites, mainly in the head and neck region of young children, whose histological features resemble those of cranial fasciitis. These lesions were composed of loosely arranged spindle to stellate cells in a myxoid background. One patient in the study had both cranial and extracranial involvement. Some histological overlap between nodular fasciitis and cranial-extracranial fasciitis was noted, but the latter lesion tended to be more uniform in appearance than nodular fasciitis with its fascicular, spindle cell features and variability in histological patterns within the same lesion, unlike the more consistently uniform myxoid appearance of the cranial and extracranial lesions. Immunohistochemically, the spindle cells of the extracranial lesions and the one case of cranial fasciitis co-expressed vimentin and smooth muscle actin. The extracranial lesions had a predilection for children in the first year of life with all cases occurring at or before 2 years of age, unlike nodular fasciitis, which is rarely seen in the first 4 to 5 years of life. The cranial and extracranial fasciitides should be differentiated from the fibromatoses that tend to locally recur, unlike the nonrecurring behavior of these lesions in common with the other types of fasciitis.

Actins↗
PubMed1999

Angiomatosis with angiokeratoma-like features in children: a light microscopic and immunophenotypic examination of four cases.

We have identified three patients with an initial clinical or biopsy diagnosis of angiokeratoma, all of whom were found to have a more extensive vascular lesion within the surgical excision. A fourth patient with identical histologic findings had no specified clinical diagnosis and his first procedure was excisional. The patients ranged in age from 7 to 16 years, and the lesions were located on the buttock, thigh, calf, and foot. Macroscopic appearances included mildly keratotic pink-red or blue-grey macules (three cases) and pink macules with focal ulceration (one case). In three of the four cases, a shave biopsy diagnosis of angiokeratoma had been made, and the extensive and deeply infiltrative nature of the vascular proliferation was recognized only at subsequent resection, at which point angiomatosis was diagnosed. In the fourth case. excisional biopsy was attempted at presentation, and the superficial morphology was angiokeratoma-like, but the vascular proliferation was present in the deep subcutaneous fat. CD31 and CD34 reactivity was present in the superficial and deep vessels in all cases, and lesional vessels were rimmed by a bland population of smooth muscle actin positive pericytes, findings that differentiate these cases from angiokeratoma, which has previously been reported to be CD34 negative. We conclude that the dilated vascular spaces that typify angiokeratoma may also be seen overlying a deep vasoformative process that is not amenable to resection, and suggest that caution should be exercised in evaluating small biopsies with angiokeratoma-like appearance.

Actins↗
PubMed1999

Congenital disseminated malignant rhabdoid tumor: a distinct clinicopathologic entity demonstrating abnormalities of chromosome 22q11.

The clinical, pathologic, and immunohistochemical features of a widely disseminated tumor with rhabdoid phenotype are described in nine infants < or = 3 months of age. Five neonates had tumor evident at birth, two of which had placental metastases. The average survival following diagnosis was < 6 weeks. None of the infants had an apparent primary tumor in either the kidney or brain. In four cases, the dominant mass involved the head and neck region, and in two cases, the primary mass was paraspinal. The histologic features were those of a high-grade, round cell neoplasm with abundant cytoplasm and containing cells with cytoplasmic filamentous inclusions. Immunohistochemical studies revealed polyphenotypic antigen expression. Genetic information was available from eight of nine cases. Karyotype analysis revealed abnormalities of chromosome band 22q11-12 in three of six tumors. Fluorescence in situ hybridization studies or molecular studies demonstrated 22q11.2 deletions in all five cases with available frozen tissue, two of which had translocations involving 22q by karyotype analysis. The similar clinical and pathologic findings in these rapidly fatal tumors in infants and the demonstration of abnormalities of chromosome 22q11 in a majority of the cases supports their histogenetic and nosologic relationship to the family of malignant rhabdoid tumors that typically occur in young children in several anatomic sites, including kidney, soft tissues, liver, and brain. Like neuroblastoma and rhabdomyosarcoma, malignant rhabdoid tumor can appear as disseminated disease at birth or shortly thereafter.

Chromosomes, Human, Pair 22↗
PubMed1999

Desmoplastic small round cell tumor of the abdomen: radiologic-histopathologic correlation.

PURPOSE: To characterize the imaging features of desmoplastic small round cell tumor of the abdomen and correlate them with the histopathologic findings. MATERIALS AND METHODS: Eleven of 14 patients with desmoplastic small round cell tumor had primary abdominal involvement. In nine of these patients (mean age, 20 years), results of imaging studies (computed tomography in nine patients, ultrasonography [US] in three) and histopathologic specimens were retrospectively analyzed. RESULTS: The hallmark imaging feature was lobulated peritoneal masses (mean number, 4.4; range, 1-17) with a mean diameter of 5.0 cm (range, 2-12 cm). Omental and paravesical tumors were each present in six patients. Retroperitoneal masses were present in three patients. The tumors were well defined and hypoechoic at US. Heterogeneity due to tumor hemorrhage or necrosis was seen in seven patients. Ascites was present in five patients. Parenchymal and/or serosal hepatic metastases, punctate calcifications, nodular peritoneal thickening, lymphadenopathy, hydronephrosis, and bowel obstruction were less common associated findings. CONCLUSION: Bulky peritoneal soft-tissue masses without an apparent organ-based primary site are characteristic of intraabdominal desmoplastic small round cell tumor. Although the findings are nonspecific, this diagnosis can be considered in adolescents and young adults with characteristic imaging findings.

Abdominal Neoplasms↗
PubMed1999

Comparison of DNA ploidy, histologic, and immunohistochemical findings with clinical outcome in inflammatory myofibroblastic tumors.

Inflammatory myofibroblastic tumors (IMTs) are uncommon spindle cell proliferations that occur in the viscera and soft tissue of children and young adults. Their biologic potential is indeterminate: 25% of IMTs recur, and rare examples undergo malignant transformation (MT). This study investigates histologic features, DNA ploidy, and expression of apoptotic regulatory and oncogenic proteins in IMTs in an attempt to identify those deviances that might correlate with aggressive behavior or MT. Twenty-four formalin-fixed, paraffin-embedded IMTs for which clinical outcome was known were evaluated for cellularity, cytologic atypia, mitoses, ganglion-like cells, inflammatory infiltrate, DNA ploidy by flow cytometric examination, and bax, bcl-2, p53, and c-myc expression by immunohistochemical analysis. Sixteen (67%) of the IMTs did not recur, 6 (25%) recurred, and 2 (8%) underwent MT. Cellular atypia was observed in 69% of the cases without recurrence, 100% with recurrence, and 100% with MT. Ganglion-like cells were present in 56, 100, and 100% of the IMTs without recurrence, with recurrence, and with MT, respectively. There was no difference in the degree of cellularity, mitoses, or inflammatory infiltrate among the outcome groups. All of the tumors expressed bax, and none expressed c-myc. Two (8%) were immunoreactive for p53, one of which recurred and one of which underwent MT. bcl-2 expression was observed in 9 (37%) of the IMTs, with no difference among the three groups. Two IMTs were aneuploid, one of which underwent MT. Neither morphologic evaluation for cellularity, mitosis, or inflammatory infiltrate nor expression of bax or c-myc were useful for prediction of clinical outcome. The combination of atypia, ganglion-like cells, p53 expression and DNA ploidy analysis, however, might be useful to identify IMTs that might undergo MT or pursue a more aggressive clinical course with recurrences.

Adolescent↗
PubMed1999

Pathology of the breast in children, adolescents, and young adults.

The pathologic spectrum of breast disease in children and adolescents is broad and includes entities more commonly seen in older patients. In general, the vast majority of breast masses in young patients are benign with fibroadenomas, gynecomastia, and macromastia accounting for the majority of surgical specimens. Malignant tumors are more likely to be secondary or metastatic than primary. Rhabdomyosarcoma and hematolymphoid tumors comprise a majority of malignant diagnoses in children. Primary carcinomas and sarcomas are rare, especially if sarcomas arising in the setting of cystosarcoma phyllodes are excluded.

Adenoma↗
PubMed1998

Nasal chondromesenchymal hamartoma: an upper respiratory tract analogue of the chest wall mesenchymal hamartoma.

Nasal chondromesenchymal hamartoma is the suggested appellation for a tumefactive process of the nasal passages and contiguous paranasal sinuses in seven children with a detectable mass in the nose. With the exception of one patient who was 7 years of age at diagnosis, the others were 3 months of age or less upon recognition of the mass. Two children were diagnosed in the first 2 weeks of life. Imaging studies showed a complex solid and cystic mass or masses filling the nasal cavity and extending into the ethmoid sinuses in most cases. Erosion of the surrounding bone, including the cribriform plate, resulted in an intracranial component in the four cases. Surgical resection was the treatment of choice despite its technical difficulties that often necessitated a combined intranasal and intracranial approach. Residual disease with continued growth in one case was the clinical outcome in two children, and the remaining five patients have not experienced any further difficulties. The piecemeal fragments of tissue disclosed a collage of histologic features, but the basic morphologic elements were well-demarcated nodules of cartilage with some variation in the cellular density and maturation of the chondrocytes, a myxoid to spindle cell stroma, focal osteoclastlike giant cells in the stroma, and erythrocyte-filled spaces resembling those of the aneurysmal bone cyst. Two of the tumors were less polymorphous or complex in their spectrum of histologic features. These nasal masses have similarities to the so-called chest wall hamartoma or mesenchymal hamartoma of the chest wall in terms of the clinical presentation in infancy and the basic cartilaginous character of both entities. There is a degree of presumption in the designation of these nasal and chest wall tumors as hamartomas because the pathogenesis has not been established for either entity.

Actins↗
PubMed1998

Pathologic evaluation of pediatric soft tissue tumors.

The subject of soft tissue tumors in children has some parallels with the same topic in adults, but many of the details clearly establish the existence of distinct differences. Most soft tissue tumors in adults arise in the extremities or in the superficial and deep soft tissues elsewhere in the body, and most tumors are neoplastic, whether they are benign or malignant. In children, some of the most common soft tissue tumors may not be neoplastic at all, but rather are malformations of the supporting mesenchymal tissues. There is a common classification of soft tissue tumors that is applicable to both pediatric- and adult-type neoplasms. Although some of the "adult"-type soft tissue tumors may occur in children, the reverse situation is very uncommon. Because pediatric soft tissue tumors are not seen with any regularity by many pathologists in a practice dominated by adult cases, there is less familiarity and more uncertainty about these tumors in children. The differential diagnosis of a malignant soft tissue tumor in a child encompasses the broad morphologic spectrum of spindle cells, round cells, or combined-pattern neoplasms. The diagnostic process is complex and may necessitate an array of ancillary studies, including immunohistochemistry, electron microscopy, and molecular diagnostics. After a decision is reached to excise a soft tissue sarcoma in a child, many of the steps in the examination of the specimen and the reporting of results for diagnostic and staging purposes are similar to those in the evaluation of a soft tissue sarcoma in an adult. However, it is important for the pathologist and other members of the multidisciplinary health care team to remember that a soft tissue tumor in a child may have genetic implications that directly influence the care of the patient and the family and for which the excised tissue offers a potentially invaluable resource for future studies.

Adolescent↗
PubMed1998

Extrapulmonary inflammatory myofibroblastic tumor: a clinical and pathological survey.

Inflammatory myofibroblastic tumor (IMT) or inflammatory pseudotumor was initially recognized in the lung, and somewhat later, a similar-appearing pathological process was reported in the liver. Presently, this tumor has been described in virtually all major organs and extrapulmonary sites with a few exceptions. It was thought initially that the IMT was nonneoplastic and represented an aberrant inflammatory response despite its gross and microscopic features of a spindle cell neoplasm. The inflammatory hypothesis about the pathogenesis has been more readily accommodated in the lung than in the extrapulmonary sites of involvement. Some cases, however, were accompanied by the constitutional symptoms and signs of an inflammatory process, which resolved in most cases after surgical resection. There were some pathological aspects of the IMT that seemingly contradicted its purely inflammatory nature, including its potential for local recurrence; development of multifocal, noncontiguous tumors; infiltrative local growth; vascular invasion; and malignant transformation. These pathological features seemed to support the hypothesis that the IMT is a neoplastic process, which has been augmented by reports that these tumors have clonal characteristics. Other studies have suggested that IMTs of the liver and spleen are associated with the Epstein-Barr virus. From the diagnostic perspective, there are several potential difficulties that the pathologist may encounter in the examination of one of these tumors. Just as it was true 60 years ago, the potential for a pathological diagnosis of one or another type of spindle cell sarcoma has not diminished with time. Because these tumors have a predilection for children, embryonal rhabdomyosarcoma is another diagnostic temptation when an IMT presents in the bladder or other hollow viscus. The IMT should probably be regarded as a soft tissue-mesenchymal tumor with an indeterminant or low malignant potential, which is a somewhat indefinite but realistic prognostic category.

Cytogenetics↗
PubMed1998

Inflammatory myofibroblastic tumor, inflammatory fibrosarcoma, and related lesions: an historical review with differential diagnostic considerations.

The concept of the inflammatory myofibroblastic tumor (IMT) has evolved from an already perplexing pathological process, the inflammatory pseudotumor, which was initially recognized in the lung and regarded as a pseudoneoplasm, although its histological features resembled a spindle cell sarcoma. Despite the pathological findings and their apparent prognostic implications, most affected individuals regardless of the primary site have had favorable clinical outcomes. The designation of inflammatory pseudotumor came to be widely accepted, although these lesions were clearly tumors or masses that may or may not have been pseudoneoplasms. An aberrant or exaggerated response to tissue injury without an established cause has generally been favored as the pathogenesis of the inflammatory pseudotumor or IMT. Once the myofibroblast was identified and its function in tissue repair was established, this cell type was found in a variety of soft tissue lesions from nodular fasciitis to malignant fibrous histiocytoma. The myofibroblast was eventually recognized as the principal cell type in the inflammatory pseudotumor, which provided the opportunity to redesignate this tumor as IMT. Some of the clinical and pathological aspects of the IMT began to suggest the possibility that these lesions are more similar to neoplasms than a postinflammatory process. Another step in the evolution of the inflammatory pseudotumor and IMT occurred with the report of a mesenteric or retroperitoneal tumor with similar pathological features to the latter tumors but with more aggressive behavior to warrant an interpretation of malignancy as an inflammatory fibrosarcoma. The IMT and inflammatory fibrosarcoma appear to have many overlapping clinical and pathological features. These tumors are histogenetically related, and if they are separate entities, they are differentiated more by degrees than absolutes. The therapeutic approach to these tumors should relay primarily on surgical resection. Studies in the future may possibly resolve the question whether the IMT and inflammatory fibrosarcoma are synonomous or closely related entities.

Diagnosis, Differential↗