Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0035412 (rhabdomyosarcoma)
 6,156 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

There are major differences between tumors in children and adults, viz. the incidence of tumor types, the predisposition of certain organs and tissues (e.g. sympathetic nervous tissue, kidney, and soft tissues) to develop tumors, problems related to tumor classification, and the biologic behavior of childhood malignancies, which are usually characterized by high rates of proliferation activity. A large number of new entities, especially in soft tissue tumors, have been published over the past years, including nodular mesothelial hyperplasia, which is a tumor-like lesion derived from peritoneal macrophages; infantile myofibromatosis, which can mimic leiomyosarcoma; intermediate grade fibrohistiocytic tumors, like dermatofibrosarcoma protuberans-related giant-cell fibroblastoma, plexiform fibrohistiocytic tumor and angiomatoid malignant fibrous histiocytoma displaying evidence of myogeneous differentiation; finally, the high-grade intraabdominal desmoplastic small cell tumor. With modern methods we can gain better insights into the biology of tumors. For example, tumors of the Ewing's sarcoma family have in common a characteristic t(11; 22) chromosomal translocation, the Ewing's sarcoma (EWS) (22q12) gene rearrangement, and the MIC2 gene. The EWS gene rearrangement is not restricted to tumors of the Ewing's sarcoma family (classic Ewing's sarcoma and malignant peripheral neuroectodermal tumor), however, but occurs in malignant melanoma of the soft tissue and in intraabdominal desmoplastic small cell tumor. Rhabdomyosarcomas (RMS) can be divided into two basic types with different prognoses: embryonal RMS, including botryoid and spindle-cell variants, and alveolar RMS, including the solid variant. The prognosis of alveolar RMS is poorer than that of classic embryonal RMS, mainly due to early tumor dissemination in alveolar RMS. The prognosis of neuroblastoma is mainly based on chromosomal and molecular biologic findings. Structural chromosome 1 abnormalities, double minute chromosomes, homogeneously staining regions, N-myc amplifications, and DNA diploidy are indications for an unfavorable outcome. Despite progress in childhood solid tumor pathology, many questions remain open, including those relating to basic chromosomal defects in germ cell tumors and the obscure nature of tumor heterogeneity.
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PMID:New entities, concepts, and questions in childhood tumor pathology. 854 1

The use of fine-needle aspiration biopsy (FNAB) in the initial evaluation of pediatric bone and soft tissue tumors is controversial, especially for those patients being considered for histiogenetic-specific therapeutic protocols, e.g., the Intergroup Rhabdomyosarcoma Study Group, the Pediatric Oncology Group. We retrospectively reviewed 33 consecutive FNAB specimens (28 primary tumors, 5 metastases) from 32 pediatric patients (< or = 19 yr of age), none of whom had a previously established tumor diagnosis. In one patient, FNAB of the primary tumor and a presumed axillary metastasis were obtained concomitantly. The cytomorphologic analysis included osteosarcoma, eight patients; rhabdomyosarcoma, five; neuroblastoma, five; Ewing's sarcoma/primitive neuroectodermal tumor, four; Langerhans' cell histiocytosis, three; and one each synovial sarcoma, undifferentiated sarcoma, infantile myofibromatosis, fibroma, chondroblastoma, chondromyxoid fibroma, and desmoplastic small round-cell tumor. Ancillary studies, e.g., immunocytochemical analysis, were used in 13 cases. Cytogenetic analysis helped to confirm one Ewing's sarcoma [t (11;22) (q24;q12)] and one synovial sarcoma [t(X;18) (p11;q11)]. With adequate FNAB specimens, a histogenetic-specific diagnosis was rendered in 27 (93%) of 29 cases, and all were correctly recognized as either benign or malignant. One case each of Langerhans' cell histiocytosis, chondroblastoma, and infantile myofibromatosis yielded unsatisfactory specimens. Fibroma and desmoplastic small round-cell tumor were initially misclassified as nodular fasciitis and rhabdomyosarcoma, respectively. Of 18 patients clinically eligible for histogenetic-specific therapy protocols, an accurate diagnosis was obtained in 17 patients. With a multidisciplinary approach and judicious use of ancillary studies, FNAB represents a highly accurate and cost-effective technique for the diagnosis of pediatric bone and soft tissue tumors, especially sarcomas, and should be considered as a viable diagnostic technique for pediatric therapeutic protocols.
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PMID:The role of fine-needle aspiration biopsy in the initial diagnosis of pediatric bone and soft tissue tumors: an institutional experience. 979 16

Infantile myofibromatosis (IM) is a rare tumor of infancy and childhood, typically presenting as a firm, nodular mass involving soft tissue, bone or viscera. Approximately one-third of cases involve the head and neck. These tumors can be solitary or multicentric. Biopsy reveals tumor cells that resemble myofibroblasts. Spontaneous regression may occur. A high degree of suspicion is necessary to differentiate this entity from other more aggressive processes histiocytosis, fibrosarcoma, rhabdomyosarcoma. We describe the case of a male infant with multicentric myofibromatosis, presenting with multiple thoraco-abdominal subcutaneous nodules and lytic mass lesions of the temporal bone and calvarium. The characteristic clinical, radiologic and histopathologic features of this process are reviewed along with diagnostic and therapeutic options.
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PMID:Multicentric infantile myofibromatosis. 986 42

Leiomyosarcoma in the pediatric age group is uncommon and incompletely characterized. A series of 20 primary leiomyosarcomas of soft tissue occurring in children younger than 16 years is presented. No significant gender predilection was observed (11 girls and 9 boys). Patient age ranged from 4 to 15 years (median, 12 years). Tumor size ranged from 0.5 to 13 cm (median, 2.5 cm); subcutaneous and deep locations were equally represented. Tumors were evenly distributed among the trunk (30%), head and neck (25%), lower limbs (25%), and upper limbs (20%). All lesions showed at least focally typical features of smooth muscle differentiation, principally in the form of fascicles of eosinophilic spindle cells with cigar-shaped nuclei. An unusual whorled growth pattern was seen in two cases. Morphologic variants including inflammatory leiomyosarcoma (one case), granular cell leiomyosarcoma (two cases), giant-cell rich leiomyosarcoma (two cases), and epithelioid leiomyosarcoma (one case) were seen. Dystrophic calcifications were present in two cases. Most lesions (85%) were low grade. Immunohistochemical staining showed positivity for alpha-smooth muscle actin in 89% of the cases, HHF-35 in 87%, and desmin in 61%. Positivity for cytokeratins, observed in 6 (43%) of 14 cases tested, was usually strong and was diffuse in two cases. Follow-up data, available in 15 (75%) patients (median duration, 49 months), showed late local recurrence in only two cases, one with progression to a higher grade lesion, and no metastasis. These results show that, although extremely rare, soft-tissue leiomyosarcomas do occur in children, in whom they usually present as small morphologically low-grade lesions that seem to behave in a relatively indolent fashion, although longer follow-up data are needed. Differential diagnosis in this setting includes infantile myofibromatosis, leiomyoma, monophasic synovial sarcoma, and spindle cell rhabdomyosarcoma.
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PMID:Leiomyosarcoma of soft tissue in children: clinicopathologic analysis of 20 cases. 1040 97

Rhabdomyosarcoma (RMS), the most common soft tissue sarcoma of childhood, displays a variety of histologic patterns. Immunohistochemistry is used extensively to distinguish RMS from its mimics. Myogenin and MyoD1, myogenic transcriptional regulatory proteins expressed early in skeletal muscle differentiation, are considered sensitive and specific markers for RMS and are more specific than desmin and muscle-specific actin and more sensitive than myoglobin. Previous studies have focused on expression of myogenin and MyoD1 in small round cell tumors. This study assesses myogenin and MyoD1 in rhabdomyosarcoma subtypes and spindle cell tumors considered in the differential diagnosis of RMS. Formalin-fixed, paraffin-embedded archival tissue from 32 RMS, 107 non-RMS, and 11 benign skeletal muscle samples was stained for myogenin and MyoD1 with standard immunohistochemical techniques. Nuclear positivity was scored on a three-tiered scale. All RMSs expressed myogenin. Alveolar RMS (ARMS) showed strong nuclear staining, especially in tumor cells lining fibrous septae and perivascular regions. In cases with a subtle alveolar architecture on routinely stained sections, myogenin highlighted and enhanced visualization of the alveolar morphologic pattern. Embryonal RMSs (ERMSs) were more variable in myogenin staining pattern and intensity. No cases of nodular fasciitis, malignant fibrous histiocytoma, malignant peripheral nerve sheath tumor, inflammatory myofibroblastic tumor, myofibrosarcoma, leiomyoma, leiomyosarcoma, or alveolar soft part sarcoma stained for myogenin. Focal nuclear reactivity was seen in desmoid (2 of 10), infantile myofibromatosis (2 of 10), synovial sarcoma (1 of 10), and infantile fibrosarcoma (2 of 10). Non-neoplastic skeletal muscle fiber nuclei stained positively for myogenin in both tumor-associated samples (25 of 40) and benign skeletal muscle samples (5 of 11). Although all RMSs were immunoreactive for MyoD1, cytoplasmic and nonspecific background staining and reactivity of nonmyoid tissues hindered its practical utility in paraffin-embedded samples in this study. Although myogenin is a highly sensitive and specific marker for RMS, it is rarely seen in other spindle cell soft tissue tumors. As previously reported, ARMS stained more strongly than ERMS. In contrast to previous studies, rare non-RMS (7 of 107) displayed focal nuclear reactivity, and entrapped atrophic or regenerative skeletal muscle fibers also stained positively. Although these are potential pitfalls in the interpretation of myogenin, careful attention to morphology and other features, to the relative paucity of myogenin-positive nuclei in non-RMS. and to the presence of entrapped muscle fibers should prevent incorrect interpretation. Because the extent of myogenin expression in RMS is much greater than in non-RMS, it is a very useful marker when interpreted in the context of other clinicopathologic data.
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PMID:Are myogenin and myoD1 expression specific for rhabdomyosarcoma? A study of 150 cases, with emphasis on spindle cell mimics. 1168 74

Abnormalities of chromosome 2p23 with expression of ALK1 and p80 occur in both inflammatory myofibroblastic tumor (IMT) and anaplastic large cell lymphoma. This immunohistochemical study investigates whether the ALK family of neoplasms includes fibroblastic-myofibroblastic, myogenic, and spindle cell tumors. Formalin-fixed paraffin-embedded archival tissues from 10 IMTs and 125 other soft tissue tumors were stained for ALK1 and p80 with standard immunohistochemistry. ALK1 and/or p80 reactivity was observed in a cytoplasmic pattern in IMT (4/10; 40%), malignant peripheral nerve sheath tumor (4/10; 40%), rhabdomyosarcoma (6/31; 19%), leiomyosarcoma (1/10; 10%), and malignant fibrous histiocytoma (1/11; 9%). No staining was observed in nodular fasciitis, desmoid, infantile myofibromatosis, infantile fibrosarcoma, synovial sarcoma, leiomyoma, or myofibrosarcoma. Alveolar rhabdomyosarcomas (4/16; 25%) displayed a distinctive dot-like cytoplasmic positivity. No cases displayed nuclear reactivity. Fluorescent in situ hybridization on 12 of the positive cases revealed a combination of abnormalities including ALK break-apart signals, nucleophosmin (NPM)/ALK fusions, or extra copies of 2p23. This study demonstrates that in addition to IMT, abnormalities of ALK1 and p80 expression with a variety of structural chromosomal changes are found in several sarcomas, especially rhabdomyosarcoma and malignant peripheral nerve sheath tumor. Although immunoreactivity in non-IMTs cannot distinguish between structural abnormalities involving 2p23 or additional copies of 2p23, it supports the concept of ALK involvement in a larger group of neoplasms, some of which have other documented clonal abnormalities. In IMT, immunohistochemistry for ALK1 and p80 is useful as an indicator of a 2p23 abnormality, but it must be interpreted in the context of histologic and other clinicopathologic data if used as an adjunct to differential diagnosis.
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PMID:Expression of ALK1 and p80 in inflammatory myofibroblastic tumor and its mesenchymal mimics: a study of 135 cases. 1221 10

Infantile myofibromatosis is a rare benign tumor of infancy and childhood that occurs in solitary, multiple, and generalized forms with similar histology but different clinicopathologic and prognostic implications. Even solitary tumors need follow-up, as the type of presentation will be determined over time. It is necessary to differentiate this entity from other more aggressive tumors, especially rhabdomyosarcoma, which is treated by chemotherapy prior to excision. We describe a prematurely born twin girl who had at birth a solitary tumor of the cervicoscapular region, involving the dermis and subcutis. A fine-needle aspiration biopsy (FNAB) specimen obtained soon after her birth suggested a diagnosis of benign neoplasm. The tumor was excised 1 month later, at which time it was significantly enlarged, ulcerated, and also exhibited worrisome histologic features including mitoses and infiltrative growth. It had the characteristic histologic pattern of infantile myofibromatosis, and myofibroblastic features of tumor cells were confirmed immunohistochemically and ultrastructurally. During the follow-up period of 39 months, there was no sign of recurrence or new tumors.
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PMID:Infantile myofibroma in a prematurely born twin: a case report. 1286 60

This article reviews some of the benign and malignant oral soft-tissue swellings that occur in children, with an emphasis on their clinical presentation, etiology, histopathology, and treatment. These lesions include single and multiple nodules, reactive lesions, and benign and malignant neoplasms. Diseases discussed include reactive gingival swelling, generalized gingival fibromatosis, melanotic neuroectodermal tumor of infancy, fibromas, vascular lesions, salivary gland lesions, and infantile rhabdomyomas. Also covered are lesions that may present in multiples, such as neuromas, multiple endocrine neoplasia type 2b, neurofibromatosis, and human papilloma virus-related benign epithelial lesions. Benign but locally aggressive and malignant neoplasms are discussed, such as aggressive fibromatosis, myofibromatosis, fibrosarcoma, and rhabdomyosarcoma.
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PMID:Soft-tissue lesions in children. 1808 94

Fibroblastic and myofibroblastic tumors comprise a morphologically diverse and biologically variable group of neoplasms that affect a wide age range. Specific entities tend to occur most frequently in infants and young children. Recent years have witnessed a proliferation of information concerning the unique biology of these tumors. In this report, I will review recent findings that serve to further characterize this group of neoplasms. Included will be newer information on fibrous hamartoma of infancy, infantile myofibromatosis, lipofibromatosis, and infantile fibrosarcoma and tumors resembling it, including primitive myxoid mesenchymal tumor of infancy and new genetic entities. I will also discuss the differential diagnosis, which includes spindle cell rhabdomyosarcoma, dermatofibrosarcoma protuberans, and calcifying aponeurotic fibroma.
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PMID:Fibroblastic and myofibroblastic tumors of children: new genetic entities and new ancillary testing. 3061 91