Primitive neuroectodermal tumor pnet is a small round cell malignancy of presumedly primitive, neuroectodermal tissue or pluripotential, migratory neural crest cells arising from the soft tissue or bone, predominantly in. They also share many demographic, radiographic and clinical similarities. Thoracic presentations of small round blue cell tumors. Small round blue cell tumors radiology reference article.
They include ewing sarcomaperipheral neuroectodermal tumor or ewing family tumors, lymphoma, mesenchymal chondrosarcoma, and small cell osteosarcoma. A generic term for tumours almost invariably malignant characterised by sheets of relatively homogenous small cells with scant cytoplasm and prominent blue nuclei, which cannot be reliably differentiated by light microscopy and require ancillary studiesin particular, immunohistochemistryto identify cell. Smallblueroundcell tumor an overview sciencedirect topics. In any case, small round blue cell tumors are malignant tumors that are hard to distinguish from each other using conventional microscopic analysis. The group of small round blue cell tumors of childhood represents a descriptive category of malignant pediatric neoplasms characterized by the presence of morphologically poorly differentiated. The most common type of round cell tumor is the mast cell tumor. Smallblueroundcell tumor an overview sciencedirect. Other small round blue cell tumors, including rhabdomyosarcoma, ewing sarcomaprimitive neuroectodermal tumor, desmoplastic round. Small similar to lymphocyte in size round round nuclei and scanty cytoplasm blue blue staining due to high nuclearcytoplasmic ratios. Small round cell tumors of bone archives of pathology. Pathology outlines desmoplastic small round cell tumor. Other areas affected may include the lymph nodes, the lining of the abdomen, diaphragm, spleen, liver, chest wall, skull, spinal cord, large intestine, small intestine, bladder, brain, lungs, testicles, ovaries, and. Differential diagnosis of paediatric small round and blue cell tumors an update ivo leuschner kiel paediatric tumor registry dept.
Histologically, many of the pediatric neoplasms have more primitive origin characterized by sheets of cells,with small, round nuclei. The term small round blue cell tumors is used to refer to a group of generally highly aggressive malignant neoplasms, seen under the microscope as monotonous proliferations of small cells with scant cytoplasm. It can be a challenge to determine the exact origin of these tumours. Oct 19, 20 small round blue cell tumors srbcts mnemonic. Pdf thoracic presentations of small round blue cell tumors. Also necrosis, cystic degeneration, glandular arrangements, signet ringlike cells, pseudorosette formations, rhabdoid cells, extensive areas of predominantly spindle cell morphology, carcinoidlike differentiation, adenoid cysticlike configuration. An update on recent molecular genetic advances shi wei, md, phd and gene p.
Advantage cytologic diagnosis of poorly differentiated. Extraosseous ewings sarcoma of sciatic nerve masquerading as an infected. Soft tissue small round blue cell tumors of childhood. Most common small round cell tumour is nonhodgkin lymphoma. Represented tumors include small cell carcinoma, ewing sarcoma, extranodal marginal zone bcell lymphoma, embryonal rhabdomyosarcoma, desmoplastic. Small blue round cell tumour definition of small blue round. Solid nests of round oval cells surrounded by cellular desmoplastic stroma. Heterogeneous group of neoplasms are characterised by the sheets of poorly differentiated cells. One of the most challenging diagnostic categories within tumors of the sinonasal tract is the small round blue cell tumors.
Tumors are formed by small, round cancer cells and are surrounded by scarlike tissue. Desmoplastic small round cell tumor dsrct is a rare neoplasm that was first described by gerald and rosai in 1989. We retrospectively analysed 41 patients treated at or referred to two regional referral centres in the uk between 1991 and 2012. The tumor has a specific genetic abnormality that helps confirm the diagnosis. Small blue cells, bone marrow infiltration, staging introduction the small round blue cell tumors are a group of neoplasms occurring usually in children and adolescents and are characterized by small round relatively undifferentiated cells.
Bone marrow infiltration in small blue cell tumours. Smallroundbluecell tumor srbct or a smallroundcell tumour srct is a group of malignant neoplasms which are seen more often in children 020 yearsold than in adults. Biopsies are usually small and limited, resulting in considerable. This category classically includes certain subtypes of sarcomas, carcinomas, lymphomas, melanoma, and neuroblastoma box 8. Desmoplastic small round cell tumor dsrct is an aggressive and rare cancer that primarily occurs as masses in the abdomen. The differential diagnosis includes sarcomas such as the ewing family of tumors eft, alveolar rhabdomyosarcoma, poorly differentiated synovial sarcoma, myxoid round cell liposarcoma, desmoplastic small round cell tumor, and cellular variants of extraskeletal myxoid chondrosarcoma, small cell and lymphoblastic. Dsrct causes multiple tumors to form in the abdomen and pelvis area, but exactly where it begins usually is not known. The group of small round blue cell tumors of childhood represents a descriptive category of malignant pediatric neoplasms characterized by the presence of morphologically poorly differentiated cells containing large hyperchromatic nuclei and scant cytoplasm. Nests and anastomosing cords of uniform appearing small blue cells within desmoplastic stroma, sometimes with tubules and pseudorosettes scant eosinophilic cytoplasm with prominent cell borders nuclei are round, oval or elongated or grooved with finely dispersed chromatin and one or two small nucleoli.
We present a pictorial essay of common and uncommon subtypes of small round blue cell tumors in the chest illustrating the characteristic radiologic findings of each lesion. The small round blue cell tumors include neuroblastoma, rhabdomyosarcoma, nonhodgkins lymphoma, and the ewings family of tumors. In histopathology, a small blue round cell tumour abbreviated sbrct, also known as a small round blue cell tumor srbct or a small round cell tumour srct, is any one of a group of malignant neoplasms that have a characteristic appearance under the microscope, i. Metastatic small round blue cell tumors in children and young women have been the subject of multiple case reports and small studies. Small blue round cell tumor of the interosseous membrane. Small round blue cell blue tumor srbct tumors characterized by small, round, relatively undifferentiated cells cytology is an excellent tool for the diagnosis of these tumors. Jun 23, 2016 the term small round blue cell is frequently used as a cursory radiologic pathological correlation of aggressive tumors throughout the body. It is usually found in the abdomen belly, but it can also occur in other parts of the body. The disparity in treatment modalities, and hence, clinical outcome in the different subsets of sbrcts makes the correct diagnosis crucial. Differential diagnosis of paediatric small round and blue. Small blue round cell tumor an overview sciencedirect topics. Because of their primitive histologic appearance many childhood tumor have been collectively referred to as small round blue cell tumor. Primary small round cell tumors of the bone are a heterogeneous group of malignant neoplasms presenting predominantly in children and adolescents.
This type of tumor accounts for roughly one quarter of all of the skin tumors that develop in dogs, and it usually strikes dogs that are older than 8 years of age. Medulloblastoma melanoma rhabdomyosarcoma retinoblastoma. These ewinglike sarcomas also show polyphenotypia, aggressiveness, and drug resistance similar to desmoplastic small round cell tumor. The term round cell tumor describes a group of highly aggressive malignant tumors composed of relatively small and monotonous undifferentiated cells with increased nuclearcytoplasmic ratio. A number of tumors share similar histology, composed of relatively uniform primitive small round blue cells. Paediatric small blue cell tumours diagnostic histopathology. These tumours are characterised by the presence of cells that are. Small round blue cell tumor srbct or a small round cell tumour srct is a group of malignant neoplasms which are seen more often in children 020 yearsold than in adults.
Certain breeds namely, those that are descended from bulldog lines have a much higher rate of tumor growth of this. Dec 21, 2018 the small round blue cell tumors include neuroblastoma, rhabdomyosarcoma, nonhodgkins lymphoma, and the ewings family of tumors. A short differential diagnosis of small round cell tumours. The accurate diagnosis of small blue round cell neoplasms can be difficult. In histopathology, a smallblueroundcell tumour abbreviated sbrct, also known as a smallroundbluecell tumor srbct or a smallroundcell tumour. In an undifferentiated tumor, showing a small round blue cell morphology, using the mnemonic mr sleep helps to highlight tumors to consider. A microscopic specimen of a tumour may show a small round blue cell tumour. Sometimes other tumor types are included in this group. Small round blue cell tumors of the sinonasal tract.
Round cell tumors of bone are a divergent group of neoplasms that largely constitute ewing sarcomaprimitive neuroectodermal tumor, small cell osteosarcoma, langerhans cell his. Malignant small round cell tumors msrct is a term used for tumors composed of malignant round cells that are slightly larger or double the size of red blood cells in airdried smears. Ewing sarcoma primative neuroectodermal tumour pnet. The first case of a dsrct was recorded in 1989, and about 200 cases have been diagnosed since then.
Nov 26, 20 desmoplastic small round cell tumour dsrct is a rare but frequently fatal sarcoma, and many of its characteristics still require further clarification. It is an extremely rare, highgrade tumor that most often causes diffuse involvement of the abdominal cavity and visceral organs. Jan 26, 2010 the diagnostic classification of small round blue cell tumors of the sinonasal area to include diverse malignancies of epithelial, hematolymphoid, neuroectodermal, and mesenchymal origin is challenging to the surgical pathologist using conventional histopathologic approaches because the cytomorphologic features are often overlapping or indistinctive. The diagnostic classification of small round blue cell tumors of the sinonasal area to include diverse malignancies of epithelial, hematolymphoid, neuroectodermal, and mesenchymal origin is challenging to the surgical pathologist using conventional histopathologic approaches because the cytomorphologic features are often overlapping or indistinctive. The cytoplasm of these cells is pale blue and contains variable numbers of. Of note, rarely one may see small round cell tumors with the polyphenotypia and desmoplasia of desmoplastic small round cell tumor but containing an ewsfli1 fusion. Blue cell tumor definition of blue cell tumor by medical. Desmoplastic small round cell tumors dsrct md anderson. Small similar to lymphocyte in size round round cells blue blue staining due to high nuclearcytoplasmic ratios. Malignant small round cell tumors pubmed central pmc. Small blue round cell tumor an overview sciencedirect. Desmoplastic small round cell tumor dsrct is a type of cancer.