Early history of pathology studies by the Intergroup Rhabdomyosarcoma Study Group.

This review chronicles the series of publications that were the result of the willingness of pathologists and clinicians in the United States to share their pathologic materials and clinical data on patients who were placed on treatment protocols for rhabdomyosarcoma and related tumors over an extended period of time. The availability of this database enabled pathologists and clinicians to study a tumor type that is rare in individual institutions, but occurs in large enough numbers to produce valid conclusions not otherwise possible. Furthermore, young investigators were challenged by this opportunity and were able to spend the necessary time to make new observations that, in retrospect, helped direct protocol designs that produced significant improvement in patient survival.

Undifferentiated sarcomas of children: pathology and clinical behavior--an Intergroup Rhabdomyosarcoma study.

Undifferentiated soft tissue sarcoma (UND-STS) is the most poorly defined tumor eligible for intergroup Rhabdomyosarcoma Studies (IRS). Recent IRS UND-STS experience was reviewed to assess the histologic characteristics and clinical behavior of undifferentiated sarcomas. Of the 1,527 patients entered on IRS-III and IRS pilot-IV, 96 had tumors classified by the IRS Pathology Committee as UND-STS.

Orbital rhabdomyosarcomas and related tumors in childhood: relationship of morphology to prognosis--an Intergroup Rhabdomyosarcoma study.

Children and adolescents who develop rhabdomyosarcoma (RMS) and related sarcomas in the orbit and treated on Intergroup Rhabdomyosarcoma protocols have had an extremely high cure rate. This study evaluates the possible relationship between their tumor morphologic subtypes and this high cure rate. The histology of tumors was re-reviewed from 229 of the 264 patients with tumors of the orbit, conjunctiva, and eyelids treated on Intergroup Rhabdomyosarcoma Studies (IRS I, II, III, and IV pilot protocols, and followed through July, 1992.

Brain heterotopia: choristoma of the back.

Heterotopic brain tissue, except in the head and neck region, is exceedingly rare. Mature neural tissue unexpectedly found in the subcutaneous tissues of the back of a toddler lacked an attachment to the central nervous system (CNS), and appeared to be unorganized glial tissue on pathologic evaluation. Appropriate clinical management of such lesions includes a suspicion of subcutaneous lesions near the CNS and evaluation to eliminate the presence of communication with the CNS, followed by surgical excision.

Brain heterotopia: choristoma of the back.

Heterotopic brain tissue, except in the head and neck region, is exceedingly rare. Mature neural tissue unexpectedly found in the subcutaneous tissues of the back of a toddler lacked an attachment to the central nervous system (CNS), and appeared to be unorganized glial tissue on pathologic evaluation. Appropriate clinical management of such lesions includes a suspicion of subcutaneous lesions near the CNS and evaluation to eliminate the presence of communication with the CNS, followed by surgical excision.

Pseudosarcomatous myofibroblastic tumor of the urinary bladder in children: a study of 11 cases with review of the literature. An Intergroup Rhabdomyosarcoma Study.

Pseudosarcomatous myofibroblastic tumor (PMT) is the result of reactive proliferation of myofibroblasts. In children, PMT of the urinary bladder can be mistaken for embryonal rhabdomyosarcoma clinically, radiologically, and by light microscopy. We are reporting the clinical, histological, and immunohistological features of 11 patients with childhood PMT of urinary bladder that were diagnosed initially as a sarcoma, usually rhabdomyosarcoma.

Classification of rhabdomyosarcomas and related sarcomas. Pathologic aspects and proposal for a new classification--an Intergroup Rhabdomyosarcoma Study.

Background: There is a need to develop a single prognostically significant classification of rhabdomyosarcomas (RMS) and other related tumors of children, adolescents, and young adults which would be a current guide for their diagnosis, allow valid comparison of outcomes between protocols carried out anywhere in the world, and should enhance recognition of prognostic subsets.

Method: Sixteen pathologists from eight pathology groups, representing six countries and several cooperative groups, classified by four histopathologic classification schemes 800 representative tumors of the 999 eligible cases treated on Intergroup Rhabdomyosarcoma Study II. Each tumor was classified according to each of the four systems by each of the pathologists.

Successful treatment of disseminated central nervous system malignant rhabdoid tumor.

Purpose: Malignant rhabdoid tumor (MRT) of the central nervous system (CNS) is pathologically identical to MRT of the kidney. CNS MRTs have the clinicopathological behavior of a high-grade intracranial sarcoma, and the children have a very poor prognosis. We report on three cases of primary CNS MRT with a review and summary of the pediatric literature with respect to demographic features and multidisciplinary management.

Agreement among and within groups of pathologists in the classification of rhabdomyosarcoma and related childhood sarcomas. Report of an international study of four pathology classifications.

Background: An International Pathology study was conducted to measure the agreement demonstrated among and within groups of pathologists involved in the categorization of childhood rhabdomyosarcoma according to four pathology classifications. Data concerning agreement and survival experience according to patho-new subtypes were used as a basis for selection of a proposed new pathologic classification.

Methods: A random sample of 800 eligible patients was chosen from the Intergroup Rhabdomyosarcoma Study II (IRS-II) and was reviewed by pathologists representing eight institutions.

Epithelioid sarcoma in childhood: An immunohistochemical, electron microscopic, and clinicopathologic study of 11 cases under 15 years of age and review of the literature.

Epithelioid sarcoma in a rare tumor and most of the cases occur in young adults. It is rare in childhood. We have been able to obtain data and histologic material for 11 patients with this disease.

Childhood rhabdomyosarcoma with anaplastic (pleomorphic) features. A report of the Intergroup Rhabdomyosarcoma Study.

The pleomorphic subtype of rhabdomyosarcoma (RMS) is now rarely diagnosed in both children and adults. Most cases previously called pleomorphic RMS are probably diagnosed as something else, most often embryonal RMS in children and malignant fibrous histiocytoma in adults. To analyze the concept of pleomorphic RMS in children, we reviewed the tumors of patients entered on the Inter-group Rhabdomyosarcoma Study (IRS I, II, and III).

Aicardi syndrome, metastatic angiosarcoma of the leg, and scalp lipoma.

An infant girl with Aicardi syndrome, scalp lipomas, and angiosarcoma of a limb is reported. The cavernous hemangioma of the leg was benign when biopsied at age 5 months but became malignant at 11 months. Angiosarcoma caused multiple distant metastases which were evident at autopsy at age 19 months.

Rhabdoid tumors of soft tissues: a clinicopathologic study of 26 cases enrolled on the Intergroup Rhabdomyosarcoma Study.

Twenty-six cases of malignant soft tissue tumors with features similar to renal rhabdoid tumors were identified among approximately 3,000 childhood sarcomas entered on Intergroup Rhabdomyosarcoma Studies I-III. The tumors consisted of polygonal cells with vesicular nuclei and prominent nucleoli and cytoplasmic intermediate filament inclusions as identified by electron microscopy and immunohistochemistry. The growth pattern was predominantly solid or solid-trabecular.

Rhabdomyosarcomas with intermediate-filament inclusions and features of rhabdoid tumors. Light microscopic and immunohistochemical study.

A group of 27 rhabdomyosarcomas (RMS) whose histology showed abundant cells containing cytoplasmic intermediate-filament globular inclusions resembling those seen in rhabdoid tumors has been identified among Inter-group Rhabdomyosarcoma Study (IRS) I-III patients (less than 1%). Their histologic subtype was embryonal RMS in 22 and alveolar RMS in 5. One-half of tumors occurred in deep muscles of the extremities, retroperitoneum, or in the pelvis.

Histopathology of childhood sarcomas, Intergroup Rhabdomyosarcoma Studies I and II: clinicopathologic correlation.

Histopathologic material from 1,782 patients registered in the Intergroup Rhabdomyosarcoma Study Committee (IRS)-I and -II were reviewed by the IRS Pathology Committee in order to provide a uniform approach to classification and correlate patient survival with tumor type. Categories considered eligible were the four types of rhabdomyosarcoma (RMS) (criteria of Horn and Enterline), extraosseous Ewing's tumor (EOE), and a group of somewhat variable undifferentiated sarcomas designated small round cell sarcoma, type indeterminate (STI). Tumors that were clearly sarcomas but were unclassifiable also were included (NOS).

Role of the thymus in histiocytosis-X.

An increasing number of reports have demonstrated that patients with histiocytosis-X show significant morphologic changes in the thymus gland. The changes include severe dysplasia, dysmorphia, and severe nonspecific involution. These findings are present in all children with histiocytosis-X who die, but can be found even when the disease is limited to one bone and is not fatal.

Significance of X granules in histiocytosis X: an ultrastructural study.

Histiocytosis X is characterized by the presence of cytoplasmic rod structures called Langerhans' cell granules or X granules (XG). It has been speculated that histiocytosis X is a Langerhans' cell disorder. This ultrastructural study was performed to quantitate the number of XG containing histiocytes in the histiocytosis X lesions.

Histopathologic prognostic factors in neuroblastic tumors: definition of subtypes of ganglioneuroblastoma and an age-linked classification of neuroblastomas.

Histopathologic prognostic factors of 295 pretreatment tumors of a total 641 neuroblastomas and ganglioneuroblastomas were studied with the use of the following proposed tumor classification. The tumors were divided into 2 groups: stroma-poor (235 cases) and stroma-rich (60 cases) according to their organizational pattern (stromal development). The stroma-poor group was classified further into 2 subgroups: favorable stroma-poor (84% survival) and unfavorable stroma-poor (4.

The diagnosis and treatment of midline neck masses in children.

Frustration in differentiating before operation among the various causes of midline neck masses stimulated us to review the clinical, operative, and pathologic findings in 176 children hospitalized for a midline cervical lump. The preoperative diagnosis was correct in 61% of these cases, the surgeon's postoperative diagnosis was correct in 83%, and the pathologist's diagnosis was correct in 98%. Only recurrence following prior excision and persistent sinus following drainage of a midline cyst were pathognomonic preoperative indicators of a thyroglossal duct cyst; these findings were present in only 6% of the cases.

Acetylthiocholinesterase staining activity of rectal mucosa. Its use in the diagnosis of Hirschsprung's disease.

Increased acetylthiocholinesterase (AchE) reactivity in the rectal lamina propria and lamina muscularis mucosae was used to diagnose Hirschsprung's disease. We processed 131 specimens with the AchE reaction; 43 were suction biopsy specimens and the rest were full-thickness specimens. Of the 68 specimens in which neurocytes were present, none demonstrated a diffuse increase in the number of nerve fibers.

Thymic changes in histiocytosis.

In order to arrive at a hypothesis of the pathogenesis of thymic changes in histiocytosis, the thymus glands from thirty-two children with histiocytosis were studied. In general, the changes were a severe loss of cortical and medullary structures rather than stress type changes in which only the cortical structure changes. The thymic changes were then classified into three main groups: severe dysplasia equivalent to that seen in congenital immune deficiency, severe nonspecific involution, and a third group designated as a dysmorphic type which resembled those with dysplasia, but, in addition, showed smaller lobules and interstitial histiocytic infiltration.

Fatal group B streptococcal pneumonia in neonates. Effects of antibiotics.

Prophylactic penicillin has been suggested to prevent neonatal group B streptococcal infections (GBS). However, there is a concern that the antibiotics may conceal significant bacteremia if post-treatment blood cultures were used to recover the etiologic agent. To clarify this point, the autopsy records of 111 cases of fatal neonatal pneumonias is infants less than one week of age for the period 1974-1978 were reviewed.

Partial splenectomy in staging laparotomy for Hodgkin's disease: an alternative approach.

Partial splenectomy, with resection of the lower one-fourth to one-third spleen, was performed in 10 children with Hodgkin's disease as part of an otherwise standard staging laparotomy. The technique proved to be safe and practical, with no postoperative complications. No evidence to date indicates that splenic involvement was missed, and all the children have thus far continued to do well, with no deaths from either underlying disease or postsplenectomy sepsis.