Clinical and image analysis of extrarenal non-central nervous system malignant rhabdoid tumors / 中华实用儿科临床杂志

Objective To demonstrate the clinical and imaging features of extrarenal malignant rhabdoid tumor (MRT) outside the central nervous system(CNS) in children and to raise awareness of the disease.Methods A retrospective database review was made of 15 patients diagnosed with extrarenal MRT outside the CNS in Beijing Children's Hospital,Capital Medical University from April 2008 to February 2017.The ultrasound,CT and magnetic resonance imaging(MRI) examinations were performed in 12,10 and 7 cases,respectively,and the clinical and imaging features were analyzed.Results The 15 patients included 8 boys and 7 girls.The age at presentation varied from 11 days to 12 years and 9 months old with a median age of 4 years old.The primary tumors were predominant solid masses,most of which were irregular,with a length of 2.20-11.70 cm [(5.87 ± 2.57) cm].The primary tumors had variable locations,relatively tended to occur in the head and neck region (6 cases) and the mediastinum (4 cases).On ultrasound,11 cases of the tumors were heterogeneous,7 cases of the tumors were accompanied with cystic change,and the solid part was mainly hypoechoic.On CT,density of 6 cases of the tumors was uneven,3 cases presented cystic change,4 cases were with calcification,and the solid part had slightly low density,with enhancement of different degrees.On MRI,7 cases of tumors showed mixed signal,5 cases with cystic change of different degrees;the solid part mainly showed isointensity or slightly hypointensity on T1 weighted image and hyperintensity or slightly hyperintensity on T2 weighted image,with restricted diffusion and predominantly heterogeneous enhancement.Medical imaging showed definite hemorrhage within tumors in 5 patients,and metastases occurred in 6 patients at the time of diagnosis,the adjacent bone destruction occurred in 3 patients,and the tumor tissue of 3 patients extended into the spinal canal.Conclusion Extrarenal MRT outside the CNS is more common in preschool kids,most of which are large and heterogeneous solid masses,often with cystic change,sometimes with hemorrhage and calcification;the solid part with restricted diffusion and inhomogeneous enhancement.Some of the patients had metastasis and local invasion.

Renal Tumors in Children / 임상소아혈액종양

Pediatric renal tumors represent a diverse group, which include Wilms' tumor (WT), renal cell carcinoma (RCC), clear cell sarcoma of the kidney (CCSK), congenital mesoblastic nephroma, malignant rhabdoid tumor of the kidney (MRTK) and primitive neuroectodermal tumor. WT (85%) and RCC (8%) are the most prevalent types. WT predominates among the 1- to 10-year age group, but RCC exceeds WT in children over age 10 years. Pediatric renal tumors are genetically, histologically and clinically heterogeneous. The overall survival for children with localized WT is currently more than 90%, whereas poorer survival rates are observed for anaplastic WT, metastatic WT, metastatic CCSK, MRTK, metastatic RCC and relapsed WT. Therefore risk-stratified treatment is important to minimize treatment morbidity while preserving survival. This review focuses on distinct characteristics of each tumor type and optimal stratified treatment.

Renal Tumors in Children / 임상소아혈액종양

Pediatric renal tumors represent a diverse group, which include Wilms' tumor (WT), renal cell carcinoma (RCC), clear cell sarcoma of the kidney (CCSK), congenital mesoblastic nephroma, malignant rhabdoid tumor of the kidney (MRTK) and primitive neuroectodermal tumor. WT (85%) and RCC (8%) are the most prevalent types. WT predominates among the 1- to 10-year age group, but RCC exceeds WT in children over age 10 years. Pediatric renal tumors are genetically, histologically and clinically heterogeneous. The overall survival for children with localized WT is currently more than 90%, whereas poorer survival rates are observed for anaplastic WT, metastatic WT, metastatic CCSK, MRTK, metastatic RCC and relapsed WT. Therefore risk-stratified treatment is important to minimize treatment morbidity while preserving survival. This review focuses on distinct characteristics of each tumor type and optimal stratified treatment.

Classical malignant rhabdoid tumor of central nervous system in 9-year-old Korean

A Malignant rhabdoid tumor (MRT) arising in the right temporoparietal lobe of a 9-year-old boy is described along with the results of an immunohistochemical study. The patient initially sought medical attention for a ptosis and right sided headache. The child underwent a subtotal resection of the tumor, followed by radiotherapy and systemic chemotherapy, but died three years after surgery. A MRT, a primary neoplasm of the central nervous system (CNS), is an entity of unknown histogenesis with a dismal prognosis, which only occurs in early childhood. Histologically similar tumors with more varied morphological features have been designated as an atypical teratoid/rhabdoid tumor. However, a classical MRT is extremely rare in the CNS and our case represents a classical CNS MRT.

Malignant rhabdoid tumor of the kidney in adults: a clinical and pathologic study / 中华泌尿外科杂志

Objective To study the pathologic and clinical features of malignant rhabdoid tumor of the kidney(MRTK),and to improve the diagnosis and treatment of the disease.Methods The clinical and pathologic data of 5 patients(4 men and 1 woman;mean age,50 years;age range,21-67 years)with MRTK(3 tumors on the left and 2 on the right)were retrospectively analyzed in combination with review of the relevant literature.Of the 5 cases,I was incidentally diagnosed with renal tumor during physical examina- tion;and 3 had gross hematuria,low back pain and discomfort,and abdominal masses.Results Radical nephrectomy was performed in all 5 cases.The tumors averaged 6.5cm in diameter.By NWTS staging,4 ca- ses had stageⅡtumors and 1 case had stageⅢtumor.Pathological features were as follows.Rhabdoid cells were characterized by eccentric nuclei,prominent nucleoli,and abundant cytoplasm containing eosinophilic inclusions that were strongly positive for vimentin and epithelial membrane antigen(EMA).Electron micros- copy showed intermediate filaments and round,irregular fibroid or whorl-like corpuscles in the cytoplasm. Follow-up was available in 4 patients(mean,6.8 months;range,3-24 months).Of them,2 died of metasta- sis or complications 12 months after operation;and 2 were alive without recurrence and metastasis for 6 months.Conclusions MRTK is a rare and morphologically distinctive neoplasm with specific findings of pathological features.The tumor has a poorer prognosis,but comparatively it is better in adults than in adoles- cents.

Malignant Rhabdoid Tumor

Primary CNS rhabdoid tumor is an extremely rare malignant tumor affecting children. Clinical, radiological, and histopathological features of malignant rhabdoid tumor are presented. Following the complete extirpation of a large tumor at the frontoparietal region, a 16-year-old male patient suffered from several local recurrences. The neoplasm is, defined by its histopathological and ultrastructural characteristics and by the pattern of its antigenicity as a malignant rhabdoid tumor(MRT).

A Case of Malignant Extrarenal Rhabdoid Tumor

Malignant Rhabdoid tumor is a rare malignant neoplasm and is morphologically similar to rhabdomyosarcoma, but is different immunohistochemically. Most malignant rhabdoid tumors occur in the kidney of infants, and are rarely reported at extrarenal sites. Since Frierson and his collagues first described the malignant extrarenal rhabdoid tumor(MRT) in children in 1985, it has rarely been reported. The neoplasm is histologically and immunohistochemically identical to a renal malignant rhabdoid tumor. There have been no previous reports of this neoplasm in Korea. An MRT of the sacroiliac bone in a 11-year-old girl is described. Five months after the initial presentation, the patient is still alive with partial response to combination chemotherapy and radiotherapy. The authors review previous reports of extrarenal MRT, and discuss the pathologic characteristics, differential diagnosis, and treatment of this rare neoplasm.

Malignant Rhabdoid Tumor of the Cerebellum in an Adult: A case report

Malignant rhabdoid tumor (MRT) is a rare and highly aggressive neoplasm of infancy and childhood. Although it was originally described and most frequently reported in the kidney, it may occur in various extra-renal sites such as the liver, thymus, and soft tissue. In the last decade primary central nervous system (CNS) MRTs have been reported in both the supra- and infratentorial compartments. Patients with CNS MRT were generally below the age of two and reports in adults are extremely rare. This is a case of primary cerebellar MRT in a 24-year-old woman, who had presented with intermittent headache, vocal cord palsy, and cerebellar dysfunctions such as abnormal finger to nose test and tandem gait. By magnetic resonance imaging scan, a well-enhancing solid mass was demonstrated at the posterior fossa filling the 4th ventricle, which extended into the medulla and cervical cord via the foramen of Magendie. Histologically, the monotonous polygonal tumor cells were arranged in diffuse sheet with occasional hemorrhagic necrosis. The nuclei were vesicular and eccentrically located due to eosinophilic, PAS-positive, intracytoplasmic inclusions with prominent nucleoli. They were diffusely or focally immunoreactive for vimentin, neurofilament, cytokeratin, GFAP, synaptophysin, and smooth muscle actin, while epithelial membrane antigen and desmin were negative. Ultrastructurally, the polyhedral tumor cells were densely packed with primitive intercellular junctions. Scanty fibrillar intermediate filaments were intermingled with cellular organelles. Postoperatively, craniospinal irradiation and systemic chemotherapy have been done and she has been free of tumor recurrence during the 13 months' follow-up periods.

Malignant Rhabdoid Tumor of the Kidney: A report of two cases: An immunohistochemical and ultrastructural study

Malignant rhabdoid tumor of the kidney(MRTK), an uncommon renal tumor found in children, is one of the most lethal neoplasms of early life. It was first recognized during a review of the first National Wilms' Tumor Study(NWTS) as an extremely aggressive neoplasm whose appearance often mimicks those of skeletal muscle tumors, but without histological, immunohistochemical, and ultrastructural markers of rhabdomyogenesis. Herein we present two cases of malignant rhabdoid tumor of the kidney, one occurring in a 6-month-old male baby, and the other in a 123-month-old girl. They presented a huge tender mass on the left upper quadrant of the abdomen. Microscopically, each case was very cellular and composed of sheets of round or polygonal cells with ample cytoplasm often containing eosinophilic filamentous inclusions and round vesicular nuclei with prominent nucleoli. Case 1 showed lymphomatoid pattern, but case 2 showed foci of several variant patterns associated with classic appearances. The tumor cells showed a strong reactivity for vimentin in both cases. Unusually, case 2 showed focal reactivity for epithelial membrane antigen(EMA), muscle specific actin, and smooth muscle actin. Ultrastructural study confirmed the presence of whorled bundles of intermediate filaments in paranuclear position, and a prominent nucleolus.

Extrarenal Malignant Rhabdoid tumor: A Case Report / 대한세포병리학회지

Malignant rhabdoid tumor is a distinct renal tumor in the pediatric age group. It was originally described as a rhabdomyosarcomatoid variant of Wilms tumor. However, subsequent studies failed to confirm myogenous differentiation, so it is now considered to be a distinct and unique type of highly malignant tumor, histogenetically unrelated. Although extrarenal forms of this tumor are rare, several examples have been described in other sites, especially the liver, prostate, paravertebral area, urinary bladder and soft tissue. We experienced a case of malignant rhabdiod tumor located in the intraabdominal cavity in a 10 month-old boy. Smear of peritoneal fluid showed round, polygonal and irregular shaped cells with large nuclei, ample cytoplasm containing Jight pink "to purple cytoplasmic inclusions, and one or a few prominent nucleoli. Immunocytochemistry revealed positivity to cytokeratin, epithelial membrane antigen and vimentin, and negativity to desmin and neuron-specific enolase. These distinct cytologic appearance and immunophenotypes were most consistent with a diagnosis of extrarenal malignant rhabdoid tumor. The cytoplasmic inclusions were correlated with eosinophilic inclusions seen in histologic section and electron microscopy confirmed this interpretation, showing filamentous aggregations in the cytoplasms of the tumor cells.

Malignant rhabdoid tumor of the kidney: a case report

Malignant rhabdoid tumor is a distinct renal tumor in children. It had been regarded as a rhabdomyosarcomatoid variant of Wilms' tumor, but it is now thought as a separate entity. We report a case of malignant rhabdoid tumor of the kidney in a 26-month-old girl who presented with a left abdominal mass. Grossly, a large mass in the lower pole of the left kidney was well encapsulated and measured 4 x 4 x 3.5cm. On cross section, it was soft and yellowish white and showed multifocal necroses. The mass was mainly located in the medial medullary portion and compressed the renal pelvis laterally. Microscopically, the tumor masses were hypercellular and anaplastic without definite blastematous elements. In larger portion, the tumor cells had abundant eosinophilic cytoplasm and hyaline globules. In addition to the classic "rhabdoid" feature, alveolar, sclerosing, and lymphomatous patterns were seen. Ultrastructurally, tumor cells with abundant cytoplasm contained tangles of intermediate filament corresponding to vimentin in immunostaining.