Infantile extrarenal rhabdoid tumor

Mediastinal malignant rhabdoid tumor in an infant: A rare case report

Mediastinal malignant rhabdoid tumor (MRT) is an exceedingly rare and aggressive neoplasm, particularly uncommon in infants. We present the case of a previously healthy 7-month-old male infant with mediastinal MRT. The patient initially presented with left eyelid ptosis and was otherwise asymptomatic. Initial investigations, including brain MRI, yielded unremarkable results, and the infant was discharged with vitamin B supplements. However, he was readmitted a week later with prolonged fever, poor feeding, diarrhea, and respiratory distress. Despite an initial diagnosis of bronchiolitis/viral respiratory tract infection, the patient's condition rapidly deteriorated. Subsequent evaluation revealed mediastinal MRT as the underlying cause. This case underscores the diagnostic challenges associated with mediastinal MRT in infants and highlights the importance of considering rare neoplastic etiologies in atypical clinical presentations.

MRI of Rhabdomyosarcoma and Other Soft-Tissue Sarcomas in Children

Soft-tissue sarcomas in children comprise a heterogeneous group of entities with variable manifestation depending on the age of the patient and the location of the tumor. MRI is the modality of choice for evaluating musculoskeletal soft-tissue tumors and plays a paramount role in both initial diagnosis and assessment of tumor response during and after treatment. Conventional MRI sequences, such as T1- and T2-weighted imaging, offer morphologic information, which is important for localizing the lesion and describing anatomic relationships but not accurate for determining its malignant or benign nature and may be limited in differentiating tumor response from therapy-related changes. Advanced multiparametric MRI offers further functional information that can help with these tasks by using different imaging sequences and biomarkers. The authors present the role of MRI in rhabdomyosarcoma and other soft-tissue sarcomas in children, emphasizing a multiparametric approach with focus on the utility and potential added value of diffusion-weighted imaging (DWI) and dynamic contrast-enhanced MRI in characterization and staging, determination of pretreatment extent, and evaluation of tumor response and recurrence after treatment. ^©RSNA, 2020.

INI1 negative sarcoma diagnosed as malignant rhabdoid tumor presenting as hydrops fetalis metastatic to the placenta: a case report and review of the literature on congenital sarcomas

Rhabdoid tumor is a highly aggressive sarcoma found in young children that occurs in the kidney, central nervous system and soft tissue sites. Rarely, it presents in the fetus or neonate and is associated with a dismal prognosis. We report a case of a 28-week gestation fetus presenting with hydrops fetalis who died soon after delivery, found at autopsy to have a rhabdoid tumor of the thoracic cavity with placental metastases and provide a review of the literature of congenital sarcomas.

Malignant Rhabdoid Tumor of the Mediastinum: A Case Report and Literature Review

Malignant rhabdoid tumor (MRT) of the mediastinum is an aggressive tumor that is extremely rare. To date, only 24 cases of the mediastinal MRT have been reported in adults and 9 cases in the pediatric age group under the age of 18 years. We report a rare case of such tumor and review the literature on its clinical and imaging features as well as its treatment and prognostic outcomes.

Mesenchymal tumours of the mediastinum--part II

This is the second part of a two-part review on soft tissue tumours which may be encountered in the mediastinum. This review is based on the 2013 WHO classification of soft tissue tumours and the 2015 WHO classification of tumours of the lung, pleura, thymus and heart and provides an updated overview of mesenchymal tumours that have been reported in the mediastinum.

Malignant rhabdoid tumor of the tongue: A rare occurrence

Malignant rhabdoid tumors (MRTs) are highly aggressive neoplasms that most commonly occur in the kidneys of young children. Malignant rhabdoid tumor of the tongue is an extremely rare entity and very few have been reported in the literature. The course of extra-renal MRT is short and its prognosis is very poor. A 19-year-old female presented with a progressive swelling and restricted mobility of the tongue for over 3 months duration. We present here a locally advanced case of MRT of the tongue, its diagnosis, management and review of the literature related to it.

Surgery and actinomycin improve survival in malignant rhabdoid tumor

Purpose. Malignant rhabdoid tumor (MRT) is an uncommon tumor that rarely occurs outside of renal and central nervous system (CNS) sites. Data from the literature were compiled to determine prognostic factors, including both demographic and treatment variables of malignant rhabdoid tumor, focusing on those tumors arising in extra-renal, extra-CNS (ER/EC MRT) sites. Patients and Methods. A systematic review and meta-analysis was performed by extracting demographic, treatment, and survival follow up on 167 cases of primary ER/EC MRT identified in the literature. Results. No survival differences were observed between those treated with or without radiation, or with or without chemotherapy. A Cox regression of overall survival revealed several independent prognostic factors. Surgical excision had a 74% (P = 0.0003) improvement in survival. Actinomycin had a 73% (P = 0.093) improvement in survival. Older age was associated with improved survival. The four-year survival, by Kaplan-Meier estimates, comparing patients less than two years old versus older than two at diagnosis was 11% versus 35%, respectively (P = 0.0001, Log-Rank). Conclusion. ER/EC MRT is a rare, soft-tissue tumor with a poor prognosis most commonly occurring in children. Surgical resection, treatment with actinomycin, and older age at diagnosis are all associated with improved survival.

Extrarenal malignant rhabdoid tumors: radiologic findings with histopathologic correlation

Extrarenal malignant rhabdoid tumors (MRT) are extremely rare. There have been only a few cases of MRT described in the literature and even fewer in the radiology literature. We present rare uterine and hepatic MRT and their computed tomography, magnetic resonance, and ultrasound imaging features with histopathologic correlation. Although the final diagnosis is based largely on histopathology, radiologists should include MRT in their differential considerations, regardless of tumor location, when they are dealing with an extremely aggressive tumor of early childhood.

Extrarenal rhabdoid tumours outside the central nervous system in infancy

BACKGROUND

Malignant rhabdoid tumours (RT) are increasingly recognized in young children, probably as a consequence of advances in accurate histological diagnosis rather than a true increase in frequency. Although typically presenting as renal tumours in infancy, extrarenal tumours outside the central nervous system (CNS) in children less than 12 months of age are now well recognized, but previous literature on their imaging features is very limited.

OBJECTIVE

To demonstrate the imaging features of extrarenal RTs outside the CNS.

MATERIALS AND METHODS

A retrospective database review was made from 1989 to 2007 of patients diagnosed with extrarenal RT in infancy, i.e. below 12 months of age.

RESULTS

There were nine patients (six boys and three girls). The age at presentation varied from 1 to 11 months (average 6 months). Tumours were located in the thorax/mediastinum (n=3), liver (n=3), neck (n=1), shoulder (n=1) and axilla (n=1). The imaging modalities used included US (n=8), CT (n=7) and MRI (n=6). Bone scan was positive in one patient, while metastases at the time of diagnosis occurred in four patients. On MRI the tumours tended to show nonspecific hypointensity on T1-W images and heterogeneous hyperintensity on T2-W images, with heterogeneous enhancement.

CONCLUSION

This is the largest radiological series of extrarenal RTs outside the CNS in infancy. In our series no imaging features were found specific to the diagnosis. A tendency towards large size and mediastinal/paravertebral location were noted. A hypodense solid component on CT and a heterogeneous hyperintensity on T2-W MR images suggest that this tumour should be considered in the routine differential diagnosis of soft-tissue tumours in infancy, in addition to rhabdomyosarcoma.

Primary thoracic myxoid variant of extrarenal rhabdoid tumor in childhood

Primary extrarenal rhabdoid tumors (RT) are now recognized as a specific entity in pediatric oncological pathology practice. We present an unusual case of a small cell myxoid variant of a thoracic RT in an infant and highlight the importance of recent molecular developments in the diagnosis of these tumors. An 8-month-old child presented with a short history of cough and shortness of breath. Imaging demonstrated a large mass occupying the majority of the thoracic cavity on the right side. A percutaneous needle biopsy of the mass showed fragments of tissue composed of malignant tumor with a predominant "small ovoid cell" phenotype and extensive myxoid change, with small nests and islands of tumor cells; occasional cells demonstrated open vesicular nuclei, prominent nucleoli, and eosinophilic cytoplasmic inclusions. Immunohistochemical staining revealed focal strong cytoplasmic positivity for cytokeratin, focal strong paranuclear cytoplasmic vimentin positivity, and INI1 staining showed normal nuclear positivity in control tissues but was negative in tumor cell nuclei. Electron microscopy demonstrated characteristic paranuclear whorls of intermediate filaments confirming the diagnosis of extrarenal malignant RT. The diagnosis of malignant rhabdoid tumor may be difficult, particularly in cases, such as the present, with a predominant small-cell myxoid phenotype. The characteristic expression patterns of cytokeratin and vimentin provide strong clues to the diagnosis, and the use of INI1 antibody now makes definitive diagnosis possible even on needle core biopsies.

Chromosome mechanisms and INI1 inactivation in human and mouse rhabdoid tumors

The human rhabdoid tumorigenesis orchestrated by INI1 inactivation is associated with specific rearrangements of chromosome 22 that correlate with preferential anatomic tumor locations. A literature review revealed significant correlations between an apparently normal karyotype and kidney tumors, monosomy 22 and cerebral tumors, and chromosome 22 translocations and tumors at other anatomic sites. In the mouse rhabdoid tumor model, specifically in the four tumors that we tested for loss of heterozygosity, neither partial deletion nor monosomy of chromosome 10 could be detected. In contrast to the human data, the only chromosome mechanism involved in the 18 mouse tumors studied appears to be a mitotic recombination or a nondisjunction-duplication. Additionally, and despite mouse tumor incidence across a variety of sites, no rhabdoid tumor could be observed in the mouse kidney. These data suggest that the chromosome mechanisms for INI1 inactivation and the selective cell survival pressure differ in human and mouse.

Rhabdoid meningioma: cytopathologic findings in cerebrospinal fluid

Rhabdoid meningioma is a recently described, rare, WHO Grade III intracranial tumor with an aggressive growth pattern and increased risk of recurrence. We describe the cytopathologic findings on cerebrospinal fluid of one such case in a 26-yr-old female who underwent resection of a left temporo-parietal mass. Cerebrospinal fluid contained abundant malignant cells with a prominent "rhabdoid" phenotype, i.e., large cells, eccentric nuclei, single prominent nucleoli, and dense eosinophilic cytoplasm. Although rhabdoid meningioma has a characteristic cytomorphology, the differential diagnosis of this tumor would involve metastatic adenocarcinoma, metastatic malignant melanoma, and other tumors with "rhabdoid" features (such as an atypical teratoid/rhabdoid tumor).

Congenital extrarenal non-central nervous system malignant rhabdoid tumor

Malignant rhabdoid tumor (MRT) is a rare tumor occurring mostly in kidneys and central nervous system (CNS). Its prognosis is not good. Occasionally, MRTs are diagnosed at or immediately after birth. A female neonate presented with MRT in the chest wall, axilla, right elbow, and bone marrow. Chest wall lesion was resected completely. Although the masses in axilla and bone marrow responded rapidly to chemotherapy, the elbow lesion increased in size. Despite intense treatment, the tumor relapsed in lungs and the patient died 12 months after diagnosis. Review of the literature showed twenty additional congenital MRTs arising from sites outside of the kidney and central nervous system were published in the literature. Eighteen patients had disseminated disease at diagnosis. The median overall survival time for all (n = 21) patients was 2.0 months (0-24 months). The only patient who survived had a localized tumor at initial diagnosis. Congenital, extrarenal, non-CNS MRTs are aggressive tumors with poor outcome.

Inv(11)(p13p15) and myf-3(MyoD1) in a malignant extrarenal rhabdoid tumor of a premature newborn

We present a premature newborn of 32 wk of gestation with a congenital malignant extrarenal rhabdoid tumor (MERT) on the right shoulder with generalized metastases. Standard histologic, immunohistochemical, molecular and cytogenetic methods were used in the evaluation of diagnostic material. Biopsy of a skin lesion showed the histologic features of a malignant rhabdoid tumor. Cytogenetic analysis of the tumor cells revealed an inv(11)(p13p15) and additionally, an increased expression of myf-3 (myogenic determination factor, MyoD1) and PAX3 was detected. These results suggest an origin of the neoplasm derived from a pluripotent cell with the potential of myogenic differentiation. Tumor suppressor genes located on chromosome 11p13 and 11p15 may play an important role for malignant rhabdoid tumor development and progression.

Translocation (8;13)(q24.2;q33) in a malignant rhabdoid tumor of the liver

A case of malignant rhabdoid tumor of the liver associated with hypercalcemia of malignancy was studied. The karyotype of the liver primary was 46,XY,t(8;13)(q24.2;q33)[7]/46,XY[13], and of the brain metastasis 46,XY,t(8;13)(q24;q33)[5]/46,XY,t(7;13)(p14;q22) [3]/46,XY,t(1;2;3)(q25;q21;p21) [2]/46,XY[13], respectively. Band 8q24 was previously reported to be rearranged in two malignant rhabdoid tumors, one renal and one hepatic.

Analysis of chromosome 22q as an aid to the diagnosis of rhabdoid tumor: a case report

Malignant rhabdoid tumor is a highly aggressive tumor of childhood that may present as a soft-tissue primary tumor. We report a soft-tissue neoplasm that was polyphenotypic by immunohistochemical expression of epithelial, mesenchymal, and neural markers and did not meet the criteria for any of the usual pediatric small round-cell tumors. The findings raised the diagnosis of rhabdoid tumor, leading to testing for WT1 mRNA and protein expression, which were positive, as has been reported for renal rhabdoid tumor. This tumor had the typical clinical behavior of rhabdoid tumor with therapy resistance and early tumor-related death. Multicolor spectral karyotyping of this neoplasm showed a balanced translocation between chromosomes 1 and 22 with breakpoints at 1p36 and 22q11-12. The latter region is commonly involved in rhabdoid tumor. This change was also identified by fluorescence in situ hybridization. This case suggests that studies of chromosome 22 may be required to distinguish rhabdoid tumor from other soft-tissue tumors.

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.