 Hello everyone, welcome back. In this video we will be discussing WHO classification of bone tumors. So bone tumors are classified into multiple categories and we will be discussing each category one by one. So the first category includes congenitumers which are characterized by formation of cartilaginous matrix. And congenitumers include following subcategories which are osteocondroma and congenitumers, congenitumers exploit fibroma, congeblastoma and congosarcoma. So except for the congosarcoma which is an element, congenitumers address all tumors are benign. So what is osteocondroma? Osteocondroma are basically bone marrow arising from the metaphysis of long bones or long flat bones. And osteocondroma can be succyl or pedunculated. They are covered by cartilaginous cap and thickness of the cartilaginous cap can be measured on MRI. And if it is more than 20 mm, it suggests development of congosarcoma. The growth of osteocondroma is stopped, satisfies your fusion. But if the growth persists in adulthood, it gains points towards melignancy. There is a condition in which multiple osteocondromas are seen and this condition is known as darpijelic radius. Next is anconroma which are benign cartilaginous tumor, most commonly seen in the metabolic cavity of long bones, and the short bones of hand and feet. And these tumors are characterized by austeritic focus with internal cartilaginous mineralization. They are seen in all age and differential diagnosis includes bone and spars and low grade congosarcoma. There is a condition in which multiple anconromas are seen and this condition is known as oleodipis. And in oleodipis it is associated with the presence of hematoma. This situation is known as marplication growth. Next in the series is congromaxyl fibroma which is a rare benign congosarcoma. It is most commonly seen in tibial metaphysis. It is eccentric and expand silent nature. It is seen in young adults and children and differential diagnosis includes ABC, non-arsipine fibroma and fibrosis failure. Next is congoblastoma which is seen as a well-defined austeritic region in the epiphysis of long bones in young adults and children. It is characterized by intense adjacent marrow edema which can be seen on MRI and congoblastomas are generally seen as a painful and swollen joint. Next is congosarcoma which is a melancholy and bone tumor that produces cartilaginous matrix. Congosarcomas are mostly seen in elderly patients and they are most commonly seen in flat bones like capillars and edus bones but they can also be seen in the bone. Congosarcoma can be primary or secondary because of de-differentiation in osteocondromas and congromas. Congosarcomas are basically slow-growing tumors with metaphysis in the age stage. Next in the category includes austrogenic tumor which are characterized by formation of osteosmetrics and austrogenic tumors include following subcategories which are osteoma, osteblastoma, conventional osteosarcoma, tiling septic osteosarcoma, peroxial osteosarcoma and very osteosarcoma. So except for this osteosarcoma, the rest of the osteosrogenic tumors are denied. So what are osteomas? Osteomas are denied matured bone growth which are exclusively seen in the venous bones like the skull and in the perinazole sinuses. So here we can see various levels of well-defined or shaped bone in the left center sinus and this osteoma can cause blockage of the perinazole sinus and it can lead to formation of pneumocytes. Next is osteoidosteoma which is seen as a loose and focused with surrounding plerosis in the diaphysis of long bones and it can have a nidus which can have central calcification. They are mostly seen in the diaphysis of long bones however they are also reported in spine, small bones of hand and feet and in particular. They are mostly seen in young adults and they are characterized by pain in the night which are typically relieved by acyclic late. The treatment of choice is radiofrequency at lesion under safety guidance. Next is osteoblastoma which is a rare tumor with most common location in the posterior element of spine in which it is characterized by lightening focus with extensive ossification. Next is conventional osteosarcoma which is the most common primary melanin bone tumor in children. It is predominantly metaphyzel in location in the long bone and most commonly seen around the knee joint in 10 to 25 years of age. But we can have a second peak in more than 60 years of age. It can be purely lighted but most commonly it is a combination of lighted and plerotic areas. It can metastasize to lung and it has a poor prognosis. It can lead to cannonball metastasizing in the lung and the patient can present this continuously whatsoever. Next is stelinjective osteosarcoma which is an uncommon variant of osteosarcoma seen in adolescent populations. It is characterized by presence of large bloodstream spaces separated by bone testra and most commonly seen around knee joint and because of presence of bloodstream spaces it can have huge fluid level on MRI which can simulate mimic aneurysmal bone cyst. Next is a osteosarcoma which is a rare variant of osteosarcoma which arises from the surface of bone. It is mostly seen over the surface of bone but in rare circumstances it can infiltrate into the marrow cavity. It is most commonly seen in the posterior aspect of this tumor. It is a slowly enlarging mass. It has a central dense ossification. In contrast to myosatis ossificus which is differential in which we can have peripheral ossification. Whereas in peroxyl osteosarcoma there is central ossification. In early stage of peroxyl sarcoma we can have strength sign which is seen in the radio lucens 9 which separates this tumor from the adjacent bone. Next is perioxyl osteosarcoma which is again a rare variant of osteosarcoma which arises from surface. It is of intermediate grade between conventional osteosarcoma and peroxyl osteosarcoma. The third category of tumors includes hematopoietic and medullary menoplasts and this category includes even sarcoma, multiple myeloma, solitary plasma cytoma of bone and primary non-hodgkin lymphoma of bone. So let's discuss here in sarcoma. Here in sarcomas are seen as in-define obsterectal lesion with multi-layered perioxial reactions. And these lesions are generally seen in less than 20 years of age. Predominantly seen in the diapitis of long bone but they can also be seen in flat bones like telial plate and ribs. Patients generally present with pain, swelling and fever with raised ESR. Differential diagnosis includes osteosarcoma, leukemia, eosinophilic granuloma and osteomalitis is the only tumor which mimics infection. Next is multiple myeloma which is the most common primary bone tumor in elderly patients. It is seen as sharply demarcated like in areas in exoskeleton or they can be present of acute pain mineralization. And this skull we can see multiple osteolithic areas are seen of varying sizes and this condition, this radiographic picture is known as raindrop skull. Multiple myelomas are characterized by proliferation of plasma cells. So these melanin plasma cells are seen throughout the body with systemic involvement and patients can have grained stones to the urea with amyloidosis and venal period. Differential diagnosis of multiple myeloma includes metastasis from various primates. Next is solitary plasma phytoma of bone which is characterized by a single osteolithic lesion which is described with plasma cells, proliferated plasma cells. It is differentiated from multiple myeloma in which there is systemic involvement but in solitary plasma phytoma of bone only a particular location in the bone is involved and solitary plasma phytoma can also be seen as an extra skeletal site in the hospital. Next is primary non-hospital lymphoma of bone which are characterized by very defined permeative osteolithic lesion in the bone. The fourth category of tumors include osteoclastic tumor or giant cell tumor which are seen as well-defined osteolithic lesion with a classically located in the epiphysis and they can have, they are generally seen as having a narrow bone of transition and therefore we can have a full or wide bone of transition as well. They are generally seen in patients with age group 20 to 40 years and there has been a confusion of epiphysis. The favorite location is around knee joint or in the distal radius and differential diagnosis includes unusual bone cysts in younger age group. So there are four characteristic radiographic features which characterize the giant cell tumor and the four radiographic features are first is patients have closed growth rate. So like in this patient we can see the growth rate is close and it's the lesion abut the articular surface. So here we can see it is abutting the articular surface and it has a non-clerotic rim. Here we can see there is no sclerosis in the rim and the lesions are mainly eccentric and expensive. Next category of tumor include notopoder tumors or caudomers. So notopoder tumors and caudomers are uncommon melignin tumors of axial skeleton and they originate from embryonic remnants of primitive notopodes. These tumors are locally aggressive and they are seen in adults of middle and elder age group. Glassid location is sacrocoxidia region most commonly seen in sacrocoxidia region followed by espino-artificial areas and tumor can have internal irregular classification. Major differential diagnosis is conrosarcoma. So if the lesion is located in the midline it is more likely caudoma and if the lesion is located paramidline or off midline then it is most likely conrosarcoma. Next category of tumor include vestular tumor which has hemangioma, epicelloid hemangioma, epicelloid hemangioma and angiosarcoma. So primary introsius hemangioma are most commonly seen in skull and vertebra and they are generally benign but in rare circumstances they can have locally aggressive nature. In such cases they can cause compression over vital structures they can cause compression over final cord and spine. So in spine they are characterized by prominent trapeculor pattern and in skull they are characterized by four field appearance. Next is lipogenic and epithelial tumors. So what are lipomas? Lipomas are rare benign lesions are predominantly seen in lower limb and it is basically the most common calcaneal bone lesion. So here we can see the presence of lipoma in the calcaneum and it has a central calcification which is known as pocket sign. In femur it can be seen in the intercopanthus region. Next is adamantinoma which is a rare primary malignant bone tumor which is exclusively seen in tibia and young edus. In rare circumstances it can metastasize to distant locations like clums and it is seen as multi-locular expansile ocular tic cortical lesions. Next category of tumors includes tumors of undetermined origins. These include aneurysmal bone cells, simple bone cells, fibrosis plasia, osteopibrous dysplasia and lengthenance cells to phytosis. So the first is aneurysmal bone cells which is characterized by benign expansile tumor in metaphysis of long bones in adolescent age groups. It can also be seen in flat bones and spines. On radiograph it has a sole bubble appearance because of presence of blood fill spaces separated by a thin bone receptor. On MRI it can show presence of fluid levels. Differential diagnoses include genital tumor, fibrosis plasia and telingectomy of plasarcoma. Next is simple bone cells also known as unicameral bone cells. It is a common benign non-neoclastic cystic lesion seen in children. It is most commonly seen in metaphysis of proximal tuberous followed by femur. It is central in location and can present with complications like psychological fracture like in this case you can see the simple bone cyst is complicated by psychological fracture and if there is presence of psychological fracture this fragment will settle down into the bone dependent location because of unicameral nature of the cyst. Next is fibrosis plasia which is characterized by presence of non-neoclastic tumor like congenital condition in which bone is replaced by fibrosis chroma. It can be monostopic or polyostopic. It can cause bending of the bone like in this case the femur is bent and this is known as shepherd-coop deformity. It can also affect bones of skull and face. Patient can present with craniofacial fibrosis plasia and it is mostly seen in children and young adults and it leads to bone expansion and remodeling. Next is osteofibrosis plasia which is a rare benign fibrosis cortical lesion which is almost exclusively seen in plebial cortex and this condition is mainly seen in less than 10 years of age and patients generally present with lytic lesion in the cortex. Next is Langer and Sinistrocytosis which is a rare multi-system disorder seen in young children and these lesions generally affect ideal skeleton. In skull the lesions are multiple punched out defects with bevel dangers and the lesions are also described as geographic skull and it can cause collapse of the vertebrate body and leads to vertebra planar. So this was all about WXL classification of bone tumors. I hope you have enjoyed the video. Thank you.