Soft tissue sarcomas in childhood

A sudden death, an aortic rupture, and an unexpected cause: a report about suspected child abuse

All unexpected deaths of children require an autopsy to determine the cause of death. In cases of aortic rupture, the immediate cause of death is easily identified at autopsy. Although the majority of aortic ruptures are caused by high-energy trauma, other causes should not be missed.We present and discuss the case of a 29-month-old child who died suddenly at home. Her recent medical history and the ecchymotic lesions observed on external examination of the body appeared potentially suspicious of physical abuse. The autopsy concluded that death was due to complete rupture of the abdominal aorta with associated vertebral disjunction. At first glance, the overall forensic picture could suggest a traumatic death. However, careful inspection of the retroperitoneum revealed a discrete atypical mass of infiltrative tissue within the hematoma. Histopathological examinations confirmed tumor proliferation of the soft tissues, triggering vascular and spinal injuries. Other paraneoplastic elements or metastases were ultimately revealed (orbital and subcutaneous). Overall, this was a rare and fatal case of abdominal aortic rupture induced by tumors. Due to the mechanisms and the forces needed to cause vertebral dislocations and aortic rupture, the combination of the two is highly suggestive of child abuse when an accidental traumatic history is absent or inconsistent with the injuries. Nevertheless, this case illustrates the importance of a systematic and rigorous forensic examination, rather than ignoring other possible diagnoses.

Rhabdomyosarcoma

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in children and represents a high-grade neoplasm of skeletal myoblast-like cells. Decades of clinical and basic research have gradually improved our understanding of the pathophysiology of RMS and helped to optimize clinical care. The two major subtypes of RMS, originally characterized on the basis of light microscopic features, are driven by fundamentally different molecular mechanisms and pose distinct clinical challenges. Curative therapy depends on control of the primary tumour, which can arise at many distinct anatomical sites, as well as controlling disseminated disease that is known or assumed to be present in every case. Sophisticated risk stratification for children with RMS incorporates various clinical, pathological and molecular features, and that information is used to guide the application of multifaceted therapy. Such therapy has historically included cytotoxic chemotherapy as well as surgery, ionizing radiation or both. This Primer describes our current understanding of RMS epidemiology, disease susceptibility factors, disease mechanisms and elements of clinical care, including diagnostics, risk-based care of newly diagnosed and relapsed disease and the prevention and management of late effects in survivors. We also outline potential opportunities to further translate new biological insights into improved clinical outcomes.

MicroRNAs for the pediatric otolaryngologist

The scope of pediatric otolaryngology is broad and encompasses a wide variety of diseases in which the fundamental phenotype-causing abnormality exists at the level of gene regulation and expression. Development of novel molecular biology instruments to diagnose disease, monitor treatment response, and prevent recurrence will facilitate the delivery of appropriate surgical and adjuvant medical treatments with lower morbidity. MicroRNAs (miRNAs) have emerged as a relatively new class of molecules that directly modulate gene expression and are abnormally expressed in a multitude of disease processes including those within the scope of pediatric otolaryngology. Functionally, miRNAs control multiple cellular functions including angiogenesis, cell proliferation, cell survival, genome stability, and inflammation. These short, non-protein coding RNA molecules are present and stable in tissue, blood, saliva, and urine, making them ideal disease biomarkers. The simple structure of miRNAs and their ability to directly modulate the expression of specific genes lends exciting therapeutic potential to miRNA-based therapies. Here we review the current literature of miRNAs as it relates to diseases within the scope of pediatric otolaryngology, and discuss their potential as diagnostic biomarkers and therapeutic targets.

Mesenteric leiomyosarcoma in a 13-year-old boy

Mesenteric leiomyosarcoma occurs most commonly in middle-aged individuals. Primary tumors of the mesentery are uncommon in pediatric and adolescent patients, and primary mesenteric leiomyosarcoma is particularly rare. Accurate preoperative diagnosis of mesenteric soft tumor is generally difficult. We describe a case of leiomyosarcoma arising from the ileal mesentery in a 13-year-old boy. The diagnosis was based on histopathologic evaluation using immunohistochemical staining and gene analysis.

Primary synovial sarcoma arising in the parotid region diagnosed by fluorescence in situ hybridization

Synovial sarcomas account for 5% of pediatric soft tissue sarcomas, and primarily arise in the extremities. We report a case of synovial sarcoma in the parotid region. A 29-year-old woman presented with a 3-year history of a slow-growing, slight painful swelling in the preauricular region. The patient underwent right deep parotidectomy preserved with facial nerve. In immunohistochemistry, the epithelial cells were positive for cytokeratin AE1/3 and epithelial membrane antigen. The stromal cells were immunoreactive for vimentin and BCL2. The both types of cells were positive for CD99. The SYT-SSX fusion gene from chromosomal translocation was detected by fluorescence in situ hybridization in this case.

The eye in malignant disease

The eye and its adnexae (the extraocular muscles, orbit, orbital walls and eyelids) can be involved in malignant disease, either as the primary source of the tumour or as a site of secondary metastatic involvement. Indeed, there is a wide variety of different tumours which are known to affect the eye, this diversity being a consequence of the richness of the ocular tissues present. In addition, disorders of vision or eye movements may be the presenting signs and symptoms of intracranial malignancy.

Primary meningeal rhabdomyosarcoma in a child with hypomelanosis of Ito

Intracranial rhabdomyosarcomas are rare neoplasms, and those thought to be primary meningeal tumors are even more rare. Hypomelanosis of Ito is a neurocutaneous disorder believed to involve a defect in cells of neural crest origin. We report the case of a 15-month-old boy with hypomelanosis of Ito who developed a primary meningeal rhabdomyosarcoma. The patient initially presented with hydrocephalus and 2 months later developed neurologic signs localizing to the spinal cord. Radiologic studies revealed widespread leptomeningeal enhancement with compression of the spinal cord at C5-C7. A brain biopsy revealed a tumor diffusely involving the meninges. Microscopically, the tumor was composed of rhabdomyoblasts, many of which showed prominent cross-striations on routine hematoxylin-eosin staining. To the best of our knowledge, this is the first reported case of meningeal rhabdomyosarcoma in a patient with hypomelanosis of Ito and the fourth reported case of a primary meningeal rhabdomyosarcoma reported in the world literature.

Myc oncogene expression and nude mouse tumorigenicity and metastasis formation are higher in alveolar than embryonal rhabdomyosarcoma cell lines

Accumulated clinical evidence suggests that alveolar rhabdomyosarcoma (ARMS) is more aggressive than embryonal rhabdomyosarcoma (ERMS). Here, we study six childhood rhabdomyosarcoma cell lines, three ERMS and three ARMS. We have assayed the ability of the tumor cells to grow in culture and in nude mice as well as their propensity for pulmonary metastasis formation by tail vein injection. We also compared levels of c- and N-myc oncogene expression and DNA copy number. We find no correlation of histologic tumor type (i.e. ERMS versus ARMS) with growth rate in culture, but we do find suggestive correlations of histologic type with tumorigenicity (mean tumor diameter in millimeters at 6 wk: ARMS 30, ERMS 10; p1 = 0.1) and metastasis formation (ARMS 12, ERMS 0; p1 = 0.1). These properties also correlate with uniform greater overexpression of c-myc in ARMS (mean 39.3-fold, range 16-83) compared with ERMS (mean 5.3, range 4-8) (p1 = 0.05, control fibroblasts = 1). Although c-myc was often amplified in vitro (four of six lines), there was no correlation with histologic type (2/3 ARMS, 2/3 ERMS). These data on rhabdomyosarcoma cell lines derived from verified ERMS and ARMS tumors support the impression from previous clinicopathologic observations that ARMS is a more malignant form of rhabdomyosarcoma than ERMS.

Soft tissue sarcoma of the hand in children: clinical outcome and management

Soft tissue sarcomas (STS) of the hand are rare in children and adolescents. From 1965 through 1995, 18 children with STS of the hand were treated at our institution. Rhabdomyosarcoma (RMS) was diagnosed in 11 patients; alveolar histological results predominated (7 of 11 cases). Seven patients presented with metastatic disease and died 4 to 23 months (median, 9 months) from diagnosis; their surgical treatment comprised above-elbow amputation (n = 1), local excision (n = 1), and biopsy (n = 5). For the four patients who presented with localized RMS, surgery consisted of wide local excision (n = 1), local excision (n = 2), or ray amputation (n = 1). With an average follow-up of 5.5 years (range, 4 months to 18 years), 3 of the 11 patients diagnosed with RMS still survive (27%). The remaining seven patients presented with nonrhabdomyosarcomatous soft tissue sarcoma (NRSTS); the most common histological variants were epithelioid and malignant fibrous histiocytoma (two cases each). Surgical treatment for these patients comprised ray amputation (n = 3), wide local excision (n = 3), excisional biopsy (n = 1), and regional lymph node dissection (n = 3). One patient received adjuvant multiagent chemotherapy; three patients received supplemental radiotherapy. Six of the seven (85%) patients are alive with no evidence of disease at an average follow-up of 4.7 years (range, 6 months to 12 years).

Soft tissue sarcoma of the head and neck in children and adolescents

BACKGROUND

The experience of one institution in treating soft tissue sarcomas of the head and neck in a pediatric population is presented.

METHODS

Case materials of 134 patients younger than 20 years who were referred to the University of Texas M. D. Anderson Cancer Center between 1970 and 1989 for treatment of sarcoma of the head and neck were retrospectively reviewed. Patients with rhabdomyosarcoma underwent multimodality treatment consisting of surgery, irradiation, and chemotherapy. Wide resection was the treatment used for patients with nonrhabdomyosarcomatous soft tissue sarcomas (NRSTS). Adjuvant chemotherapy and irradiation were used to treat high grade neoplasms and residual disease. The clinical response to therapy was measured in terms of the disease-specific survival rate.

RESULTS

Seventy-nine of 134 patients presented with untreated or biopsy-proven disease. Fifty-six had rhabdomyosarcoma and 23 had

NRSTS

At 2 and 5 years, the disease-specific survival rates for patients with rhabdomyosarcoma were 74% and 63%, respectively, and patients with NRSTS had 80% and 75% disease-specific survival rates at 2 and 5 years, respectively.

CONCLUSIONS

Rhabdomyosarcoma of the head and neck in children is effectively treated with multimodality therapy. Prognostic indicators for rhabdomyosarcoma include completeness of tumor resection and the development of recurrent disease. Aggressive surgical resection is the treatment of choice for patients with

NRSTS

Prognostic indicators for NRSTS include completeness of tumor resection and the development of recurrent disease.

Electrodiagnostic testing and carpal tunnel release outcome

This study examined the correlation of electrodiagnostic test results and symptom outcome after carpal tunnel release. After meeting specific inclusion and exclusion criteria and failing conservative management, 167 patients (227 hands) underwent an open carpal tunnel release. Of 99 hands with a positive electromyographic/nerve conduction velocity study, 93 (93%) had resolved or improved symptoms. This finding compares with a 93% resolution or improvement rate in 27 hands with a negative electromyographic/nerve conduction velocity study and a 93% resolution or improvement in postoperative symptoms in 101 hands on which no electromyographic/nerve conduction velocity study had been performed. Statistical analysis demonstrated no significant differences in final symptom status after carpal tunnel release when comparing patients who had positive, negative, or no electrodiagnostic preoperative testing. Given specific clinical criteria for establishing the diagnosis of carpal tunnel syndrome, electrodiagnostic testing does not appear to correlate with improved final symptomatic outcome after carpal tunnel release.

The painless soft tissue mass in childhood--tumour or not?

Soft tissue malignancies are uncommon in adults and even rarer in children. Twelve children presented to the radiology department over a three-year period with a clinical diagnosis of a malignant lower limb mass. This diagnosis was usually based on the presence of a firm, painless mass. However, imaging revealed a heterogeneous group of benign pathologies: haemangioma (two cases), haematoma (two cases), aneurysm (two cases), and one case each of infection, myositis ossificans, Baker's cyst, lipoma, muscle rupture, and venous malformation. During the same period there was only one malignant soft tissue neoplasm. A variety of imaging techniques were used but ultrasound combined with colour flow Doppler was the single most helpful modality. The radiological diagnosis were confirmed by biopsy, surgery or clinical follow-up.

MYCN gene amplification in rhabdomyosarcoma

BACKGROUND

Amplification of the MYCN oncogene, formerly known as N-myc, has been seen in several malignant tumors, particularly neuroblastoma, where its association with a poor clinical outcome is the clearest example of a clinically relevant oncogene mutation in any human cancer.

METHODS

The incidence and clinical significance of MYCN amplification in rhabdomyosarcoma (RMS) was assessed by Southern blot analysis in this retrospective study of seven alveolar RMS and six embryonal RMS.

RESULTS

MYCN amplification (4- to 13-fold) was present in three of seven alveolar RMS (42.9%) but in none of the embryonal RMS. There was no significant difference between the clinical behavior of the MYCN-amplified and unamplified tumors, and no correlation was found with the light microscopic appearances of the tumors or with desmin immunoreactivity.

CONCLUSIONS

The findings are compatible with previous studies that demonstrated cytogenetic evidence of gene amplification in RMS, and help to clarify conflicting reports in the literature about MYCN amplification in alveolar and embryonal RMS. The results raise the possibility of important biologic differences between these subtypes of RMS, differences that warrant further investigation.

Nonrhabdomyosarcoma in children: prognostic factors influencing survival

In approximately 90% of children with nonrhabdo soft tissue sarcoma (NRSTS) local control can be obtained by either surgery alone or with supplemental radiation. The disease-free survival is, however, only about 50%. To determine factors influencing overall survival, we undertook a retrospective review of the 154 children with NRSTS. We used the American Joint Committee on Cancer staging system (1988), using invasiveness, size, and a Pediatric Oncology Group grading system. Using this system we documented that 72 (46%) were noninvasive (T1) lesions. Of these 72 patients 50 (70%) were < or = 5 cm A, and only 9 (18%) had G3 lesions. Overall 7/72 (10%) have died. In contrast to the 82 patients with invasive (T2) lesions, 65 (79%) were > 5 cm (B), with approximately 80% G3. Of all T2 lesions, 56/82 were G3 (65%). Here, overall 58/82 (70%) have died, primarily because 49/58 had G3 lesions. Important prognostic factors include primarily G3 lesion 52/71 (73%) mortality, as compared to 13/83 (15%), G1-2 dying. Children with invasive lesions tended to have larger tumors, 50/65, most of which were higher grades. We feel that patients with histologic grade G3 and T2 lesions should be enrolled in effective chemotherapy protocols.

Intussusception and leiomyosarcoma of the gastrointestinal tract in a pediatric patient. Case report and review of the literature

Intestinal leiomyosarcoma is a rare tumor in infants and children; only 46 cases have been reported in the English literature. Presenting signs and symptoms include abdominal pain and gastrointestinal obstruction and bleeding. We describe a neonate with the unique presentation of ileocecal intussusception accompanying an ileal leiomyosarcoma. In contrast to adult patients, where intussusception is associated with smooth muscle tumors in 30% of cases, leiomyosarcoma and subsequent intussusception is rare in infancy and childhood. The overall prognosis for long-term survival is similar for both pediatric and adult patients with leiomyosarcoma of the intestinal tract, with a five-year survival in reported cases of 53% and 40%, respectively.

Pediatric soft tissue sarcomas of nonmyogenic origin

Nonrhabdomyosarcoma soft tissue sarcomas (NRSTS) are relatively rare tumors, which nonetheless constitute 50% of the soft tissue sarcomas seen in the pediatric population. The prognosis for these tumors is good, with 92% of patients in our series alive and 61% free of their disease at 5 years follow-up. The most important prognostic factor among our 35 patients was the grade of the tumor. More than 70% of our patients with grade I or II lesions are disease-free at 5 years, compared to only 39% of patients with grade III lesions. The patients with the best outlook are those who can be treated with surgery alone as the definitive care for this disease. Resection remains the primary treatment modality in NRSTS, whereas, unlike the treatment of rhabdomyosarcomas, the value of radiation therapy and chemotherapy in treating NRSTS remains undefined.

Synovial sarcoma in the neck of an eleven month old girl

Synovial sarcomas are rare primary tumors of the head and neck in any age group. We present a case of primary synovial sarcoma arising in the neck of an 11-month-old girl.

Molecular differential pathology of rhabdomyosarcoma

Tumors of the soft tissues are classified histogenetically according to their phenotypic resemblance to normal adult tissue. Here we describe molecular approaches that make it possible to distinguish between one class of these tumors, rhabdomyosarcoma, and other small-, round-cell tumors. We show that the ascertainment of specific genotypic changes can be used to distinguish further between the embryonal and alveolar subtypes of rhabdomyosarcoma. We tested our model in two ways: first, in a retrospective analysis of diagnostically problematic cases of undifferentiated, small-cell tumors and, second, in a blind study of pediatric tumors. Rhabdomyosarcoma was correctly identified in all cases using this strategy alone. The underlying simplicity of the strategy used to define rhabdomyosarcoma subtypes with molecular markers suggests a model by which tumors can be unequivocally identified, which may apply equally well to other human solid tumors.

A contemporary view of neoplasms in children. The pathologist's perspective

The diagnosis of childhood malignancy is a complex endeavor that requires the cooperation of the clinician and pathologist. On occasion, potentially problematic situations arise when a biopsy cannot answer all of the questions or is nondiagnostic. Delays may occur before a final diagnosis is possible in an especially complicated case that requires several time-consuming studies. The pathologist should appreciate the pressure placed on the clinician to initiate treatment and, in turn, the clinician should realize that several steps are necessary before the pathologic examination can be completed.

Present-day concepts in the management of sarcomas in children

1. NRSTS tumors represent 20-20% of all soft tissue sarcomas. In only the extremity primary are both RMS and NRSTS occurring with almost equal frequency. 2. Modern diagnostic imaging studies are invaluable to staging and preoperative planning. 3. The most important need is to standardize biopsy techniques, since an ill-conceived biopsy has an adverse effect on the definitive surgical procedure. 4. Standardization of surgical procedures is necessary to adequately define extent of local resection varying with site, type of tumor, and its biological behavior. Less radical procedures do not seem to have had an adverse effect in local control or survival as is evidenced in RMS of the orbit, vagina, and bladder. 5. Though complete surgical extirpation is the treatment of choice in RMS, incomplete surgical excision leaving microscopic disease can result in adequate local control following chemotherapy and radiation therapy. However, less than optimum responses to chemotherapy in the NRSTS makes it imperative that efforts be made to completely resect these lesions. 6. It is in the realm of initially unresectable primary lesion that the surgical oncologist's role be refined. Consideration here includes: (a) use of newer surgical techniques such as laser, or free microvascular grafts, (b) protocols to define the optimum timing of delayed surgery following preoperative chemotherapy with or without radiation therapy.

Muramyl tripeptide: an effective immunotherapy in the surgical setting for pediatric abdominal neoplasms

A potential complication of intraperitoneal neoplasms is the occurrence of peritoneal metastases. This experiment hypothesizes that resident peritoneal macrophages, activated by muramyl tripeptide (MTP-PE), will destroy peritoneal tumor. MTP-PE is a lipophilic derivative of the mycobacteria cell wall component responsible for induction of cellular immunity and activation of macrophages to a tumoricidal state. A transplantable murine fibrosarcoma, MCA-F was utilized. Murine hosts were challenged intraperitoneally with 5 X 10(3) MCA-F cells. Treatment with MTP-PE micelles or liposome-encapsulated MTP-PE was initiated 48 hours prechallenge and on the day of tumor challenge and continued at 72 hour intervals for the subsequent 21 days. Hosts were observed for survival. At 45 days after tumor challenge, all untreated control animals had succumbed to overwhelming neoplastic disease. In contrast, 30% of the mice treated with liposome-encapsulated MTP-PE (P less than .05) and 50% of the animals treated with MTP-PE micelles (P less than .001) remained alive at 60 days. Followed for 120 days, 20% of MTP-PE micelle treated mice are long-term survivors. These results suggest that control of intraperitoneal seedings may be achieved with MTP-PE when the tumor burden is small.