It accounts for about 4% of all osteosarcomas and, although rare, it is the most common type of osteosarcoma of the bone surface .Approximately 8% to 25% of the cases reported in literature developed dedifferentiation, The pathogenesis of parosteal osteosarcoma is discussed. PAOS represents 46% of OS and commonly affects the posterior aspect of the distal femur. However, myocardial metastasis of a parosteal osteosarcoma is an event that was not found in the literature. Skip metastasis, conventional osteosarcoma demonstrating, 120 Slipped capital femoral epiphysis (SCFE), 421427 additional examples, 425437 Periosteal osteosarcoma, or PO, is a rare type of bone cancer. The lung mass was found to be a metastasis from parosteal osteosarcoma and the biopsy of the forearm mass revealed a There was no evidence of local recurrence or distal metastasis after a 1-year follow-up. The prognosis for parosteal osteosarcoma is better than that for conventional osteosarcoma, as the 5-year overall survival rate is 86%-91% for the former but 53%-61% for the latter. Using comparative genomic hybridization (CGH) and fluorescent in situ hybridization (FISH), we were able to confirm a late relapse of the initial osteosarcoma. osteosarcoma is regarded as low grade and tends to have the best prognosis after wide resection and has minimal metastatic potential. Because of an increase in occurrence of cancer and patient-specific treatment options, the detection and classification of cancer becomes a difficult process. Metastatic carcinoma : As is obvious, the presence of multiple radiographically evident bony lesions should be investigated to rule out the more likely possibility of metastatic disease to the skeleton, rather than the rare multifocal osteosarcoma. CONCLUSION:The review leads to the conclusion that the occurrence of metastasis from parosteal osteosarcoma can occur in up to 38% of the cases, in spite of its relatively low aggressiveness. DESCRIPTORS: Parosteal. Patients typically present between ages 30 and 40 with a painfless mass. A 12yearold Maltese terrier was evaluated for progressive tetraparesis and neck pain. Spread to the pancreas is extremely rare and is undocumented in the low-grade histologic subtype of parosteal osteosarcoma. Parosteal osteosarcoma can be treated successfully with wide excision of the primary tumor alone. Surgery that removes the tumor and spares the limb is used whenever possible. The case of a 50-year-old man who presented with nontraumatic swelling of the left upper arm and there are no signs of tumor recurrence or metastasis and the proximal osteotomy has healed nicely; the distal fixation osteotomy exhibits delayed healing. Parosteal osteosarcoma ; colon obstruction ; metastasis. Correct diagnosis of parosteal osteosarcoma is challenging for an orthopedic surgeon. Patient expired 6 months later after a course of chemotherapy and radiation due to generalized metastatic disease and multiple organ failure. Parosteal osteosarcoma is slow-growing and late to metastasize; accordingly, it carries a better prognosis than other variants of osteosarcoma. e.g. As they are frequently metaphyseal in location, large parosteal osteosarcomas or those with deep medullary invasion may require limb salvage, including joint replacement. It accounts for about 4% of all osteosarcomas and, although rare, it is the most common type of osteosarcoma of the bone surface .Approximately 8% to 25% of the cases reported in literature developed dedifferentiation, It grows primarily into the surrounding soft tissues, but 67% (1954/2898) 3. Aim: We report an unusual case of abdominal mass recurrence of parosteal osteosarcoma of the left distal femur treated eight years Grades metastasis varies from 6 to 32 months, ria1. Parosteal Osteosarcoma Periosteal Osteosarcoma Telangiectatic Osteosarcoma Well-differentiated liposarcomas exhibit < 10% local recurrence rates and <1% chance of metastasis and almost complete survival. Taulescu MA, Carlson CS, Amorim IF, De Fatima Grtner M, Frca L, Gal AF, Ctoi C. J Am Vet Med Assoc, 245(10):1103-1105, 01 Nov 2014 In the present paper, we report a case of parosteal osteosarcoma involving the maxilla. Using comparative genomic hybridization (CGH) and fluorescent in situ hybridization (FISH), we were able to confirm a late relapse of the initial osteosarcoma. of diagnosis or at the time of recurrence [3]. The most common location is the posterior aspect of distal femur (thigh bone), in approximately 70% of the cases. The natural history of this disease may extend to five years or longer before metastasis occurs. The patient developed lung metastasis and a mass in the interosseus membrane of the forearm proximally to the osteotomy. Abstract. Parosteal osteosarcoma is a locally aggressive malignant tumor, and resection with a wide margin is the most appropriate treatment. Among these tumors, the osteosarcoma is the commonest primary malignant tumor, comprising of approximately 35% of all bone malignant tumors, followed by others like chondrosarcoma (25%), Ewing sarcoma (EWS) (16%), and chordomas (8%). I NTRODUCTION. Involvement of the oral cavity is rare. Parosteal osteosarcoma is a low-grade, malignant bone tumor that usually arises on the metaphyseal surface of long bones. Osteosarcoma. Osteosarcoma occurring as a primary tumour in the rib is rare and there are only a few case reports existing in the literature as a primary parosteal osteosarcoma of the ribs [2, 3]. Osteosarcoma is the most common primary malignant tumor of bone in adolescents and young adults. 1 Most are secondary osteosarcomas occurring after prior radiation therapy, pagetoid osteosarcomas, or metastases. A diagnosis of parosteal osteosarcoma (POS) at the femoral diaphysis was made following a diagnostic workup. Parosteal osteosarcoma is a sarcoma that has it's origin on the surface of the bone. In reviews of parosteal OS, 1,2,5,6 the incidence of dedifferentiation is 16%. Large ossified mass in centre. Metastasis mostly occurs with high-grade tumors disseminating to the lungs and other bones. The vast majority involve the metaphysis of the femur, humerus, or tibia. curs in the third and fourth decades Copeland, parosteal osteosarcoma is a slow-growing malignant tumor arising on the surface of the metaphysis of long bones, representing 5% of all primary osteo - Metastases of dedifferentiated sarcoma usually contain a dedifferentiated component. Parosteal osteosarcoma is a low-grade, malignant bone tumor that usually arises on the metaphyseal surface of long bones. Parosteal osteosarcoma represents a low-grade, well-differentiated type of cortical surface osteosarcoma with a relatively better prognosis. dedifferentiated high grade Parosteal osteosarcoma was rendered. present in 25% of primary lesions and 50% of metastatic lesions. In contrast to osseous metaplasia, these lesions have foci reminiscent of parosteal osteosarcoma or low grade central osteosarcoma (Am J Surg Pathol 2010;34:1361) Pitfalls and tips : Nuclei with sharply outlined vacuoles (Lochkern cells) are enlarged and can appear hyperchromatic but are normal adipocytes cut in cross section It also can form on the surface of bones in the arms called the ulna and the humerus. Osteosarcoma is defined as the primary malignant mesenchymal bone tumor where the malignant tumor cells directly form the osteoid or bone or both. e.g. Some larger osteosarcomas may break through the bone and grow into the surrounding tissue including muscle, tendons, or the joint space. Parosteal osteosarcoma represents the well-differentiated end of surface osteosarcoma, which typically consists of a slow-growing lesion that assumes a significantly better prognosis than conventional osteosarcoma . The most common site for parosteal osteosarcoma is the posterior distal femur. Parosteal osteosarcoma. The patient developed The term dedifferentiated parosteal osteosarcoma has been widespread pulmonary metastasis and died 6 months after applied to these lesions [3]. Treatment and prognosis The EOCME is accredited by the Osteochondroma. Periosteal osteosarcoma. Osteo = bone/osteoid tissue Sarcoma = malignant tumor of connective tissue 04/28/14 1 Parosteal OS Arise from the periosteum. Regional: The cancer has spread outside the bone and into nearby structures, or it has reached nearby lymph nodes. The periosteum is a thin layer that covers the outer surface of the bone and provides structural integrity and produces bone-forming cells. Osteosarcoma is the most common primary malignant tumor of bone in adolescents and young adults. Most common sites are the posterior aspect of the distal femur, proximal tibia, and proximal humerus. parosteal osteosarcoma. and evaluated as to the adequacy of surgical management in relation to the later development of local recurrence or metastasis or both. Surgical resection with a Metastatic rate of 2847 % for dedifferentiated tumors. Parosteal osteosarcoma, a subclass of low-grade OS, has a fibroblastic-like appearance and is limited to the surface of bone structures; however, it may gradually spread to interior bone tissues. I had the tumor on the femur above the knee 7 years ago. PURPOSE To assess the role of magnetic It is regarded as a distinct form of osteosarcoma with better prognosis than conventional osteosarcoma. It is based on 3 key pieces of information: The grade (G) of the tumor, which is a measure of how likely it is to grow and spread, based on how it looks under the microscope. Taulescu MA, Carlson CS, Amorim IF, De Fatima Grtner M, Frca L, Gal AF, Ctoi C. J Am Vet Med Assoc, 245(10):1103-1105, 01 Nov 2014 (p=0.017, p=0.002,p=0.005) The most common resection type was segmental articular resection (9 patients). However, due to the low local recurrence and metastasis rate, when it appears in the posterior surface of the distal femur, the lesion can be managed with hemicortical wide resection and biological reconstruction with hemicortical allograft. M alignant bone tumors are rarely seen in the hand. We report the case of a parosteal osteosarcoma of the distal ulna, treated with wide resection without reconstruction. In only 15% of cases, it can spread to the [] Publicationdate 2010-04-10 / update 2022-03-17. Its relatively benign course was described by Mller as early as 1843 (13), but it was not before 1947 that parosteal osteoid sarcoma, representing only 1 per Correct diagnosis of parosteal osteosarcoma is challenging for an orthopedic surgeon. Microscopically, it is composed of a low grade fibrous stroma and less mitoses and cellular atypia when compared with conventional osteosarcoma (Okada 1994). AMA PRA Category 1 CME credit for Clinical Imaging reviewers. Parosteal osteosarcoma is a low-grade tumor microscopically. 22 How common is PO? Statistical analysis of the thirty-nine patients who had had the primary treatment at our institution revealed that incomplete resection was associated with an increased risk of local recurrence and that dedifferentiation markedly increased the risk of metastasis. 1. 6.JacobsonSA.Earlyjuxtacortecal osteosarcoma (parosteal osteoma). Dedifferentiated parosteal osteosarcoma and high-grade surface osteosarcoma, the third and fourth types, are very rare and highly malignant tumors, associated with a poor prognosis. Parosteal osteosarcoma. Parosteal osteosarcoma is a low grade, well differentiated fibroblastic tumor that produces bone/osteoid (immature woven bone). 5-year relative survival rates for osteosarcoma The Editors of Clinical Imaging in conjunction with the Elsevier Office of Continuing Medical Education are pleased to offer an AMA PRA Category 1 CME credit program for registered Clinical Imaging physician reviewers who complete manuscript reviews. Fewer than 50 cases of osteosarcoma involving the hand have been reported in the literature. Surgical resection with a A slice of the radial cortex was taken Parosteal osteosarcoma occurs more often in older patients than does conventional high-grade osteosarcoma and is most common in patients aged 20 to 30 years. There are numerous types of primary osteosarcoma, including intramedullary (high grade, telangiectatic, low grade, small cell, osteosarcomatosis, and gnathic), surface (intracortical, Osteosarcoma ppt 1. Parosteal Osteosarcoma of the Distal Femur Olga D Savvidou ,1,2 Stavros Goumenos,1,2 Ioannis Trikoupis,1,2 Angelos Kaspiris ,3 Dimitra Melissaridou,1,2 Panagiotis Gavriil,1,2 Jimmy Georgoulis,1,2 and Panayiotis J Papagelopoulos 1,2 1First Department of Orthopedics, National and Kapodistrian University of Athens, Medical School, Zografou, Greece Tumors are either low grade (G1) or high grade (G2). Hence, these are malignant bone tumors. The suspicion of a recurrence of parosteal osteosarcoma, already metastatic, led to a second wide resection with no reconstruction. Marina NM, Pratt CB, Rao BN et al. slow growing & late to metastasize. Parosteal osteosarcoma is a low grade surface variant. The tumor occurs over the metaphyseal region, especially the long bones, near the knees. It is a relatively rare disease entity, comprised only 4% of all osteosarcomas and barely reported in the literature. Osteosarcoma located in the chest and pelvic bones was associated with metastatic disease; however, metastasis in two histological types, parosteal and periosteal, was infrequent. [7,10] In addition, the incidence rate of osteosarcoma was higher among male and female patients between the ages of 10 and 19. Mostly occurs at the age of 30-40 years old. Additionally, 15 dogs with appendicular osteosarcoma treated with SBRT that had metastatic disease at the time of treatment were reported to have a median survival time of 200 days, though histopathology or cytologic diagnosis of these dogs' metastatic disease was not documented in this publication . In this article we will discuss a systematic approach to the differential diagnosis of bone tumors and tumor-like lesions. Better prognosis. and one leading to distal metastasis . The lung mass was found to be a metastasis from parosteal osteosarcoma and the biopsy of the forearm mass revealed a myositis ossificans. Has the tumour spread into surrounding tissues? There was no evidence of local recurrence or distal metastasis after a 1-year follow-up. There are numerous types of primary osteosarcoma, including intramedullary (high grade, telangiectatic, low grade, small cell, osteosarcomatosis, and gnathic), surface (intracortical, The malignant bone tumor most determined was Ewing's sarcoma in 10 patients, of which two had lung metastasis and one had metastasis in the shoulder and acetabulum. They must be included in any differential diagnosis of a spinal bone lesion in a patient older than 40 years. Background : Parosteal osteosarcoma is a rare, well-differentiated, predominantly fibro-osseous variant of osteosarcoma. synovial sarcoma, 39 Bizarre parosteal osteochondromatous proliferation (BPOP), 475, 479 Blood products PVNS differential diagnosis and, 184 VM, synovial with, 188. Here we report the striking case of a 60-year-old patient who presented 16 years after the initial diagnosis of parosteal osteosarcoma of the humerus with a new extensive lung lesion. This may be either at the time amputation. However, myocardial metastasis of a parosteal osteosarcoma is an event that was not found in the literature. It arises on the surface of the bone and invades the medullary cavity only at a late stage. It usually forms on the surface of bones of the legs called the tibia and femur. Along the spectrum, parosteal osteosarcoma occupies the well-differentiated end. 2,3 Although the exact [7,10] The periosteum is a thin layer that covers the outer surface of the bone and provides structural integrity and produces bone-forming cells. 7A Lytic metastasis in invasive ductal carcinoma of the breast in such as osteosarcoma. A system commonly used to stage osteosarcoma is the MSTS system, also known as the Enneking system. High and heterogeneous signal on T2-weighted images of Grade I, II, and III tumors is not specific for the dedifferentiation of parosteal osteosarcoma component, due to hemorrhage and necrosis in large masses, therefore, high signal intensity on T1- Weighted images is not always a reliable way to predict the grade of the tumor. 1,2,3,4,5,6,7,8,9,10,11,12 Demonstration of osteoid directly formed by the malignant cells in histopathology is essential for making the diagnosis of osteosarcoma. 1 Among the primary osteosarcomas, the parosteal variant is extremely rare and there are only 6 Background: Parosteal osteosarcoma is a rare, well-differentiated, predominantly fibro-osseous variant of osteosarcoma. 1. No metastases were seen from Grade I tumours despite a number of local recurrences. Adapting to limb amputation. Patient was not a surgical candidate due to extensive metastatic disease, and difficult to access sites of metastasis. We report a rare case of dedifferentiated parosteal osteosarcoma (dd-POS) with well-differentiated multiple metastases in a 65-year-old woman with a painful firm mass on her thigh. 7% (196/2898) 5. Please rate this review topic. Osteosarcoma can spread from where it started to other areas, making treatment and recovery more difficult. Chondrosarcoma was determined in two patients and osteosarcoma in two, and amputation at an appropriate level was performed in these patients (Table 3). Distant: The cancer has spread to distant parts of the body, such as to the lungs or to bones in other parts of the body. It accounts for approximately 15% of all primary bone tumors confirmed at biopsy. Productive osteoblastic osteosarcoma of the left humerus with unilateral eye, cervical muscle, pulmonary, renal, jejunal mesentery, and liver metastases. The neurovascular involvement was related with metastatic disease, deep infections and complication related surgeries. Osteosarcoma is a kind of bone cancer which generally starts to develop in the lengthy bones in the legs and arms. Co-amplification of CDK4, SAS and MDM2 in surface osteosarcoma. This article will focus only on the metastasis involving the bony structures of the spine; please refer to the specific articles for Treatment. Dedifferentiation into telangiectatic osteosarcoma described with fluid-fluid levels on MR imaging. - parosteal osteosarcoma is distinguished from classic osteosarcoma by its much slower, less aggressive clinical course. Metastases to the lung in parosteal osteosarcoma occur both later and with considerably less frequency compared with metastases in conventional osteosarcoma [1, 2]. Parosteal osteosarcoma is a locally aggressive malignant tumor, and resection with a wide margin is the most appropriate treatment. Because of an increase in occurrence of cancer and patient-specific treatment options, the detection and classification of cancer becomes a difficult process. Partial osteosarcoma is a slowly growing subtype of bone-forming cancer that arises from the outer layer of the periosteum. - about 10% of parosteal tumors exhibit areas of dedifferentiation into high grade sarcoma & are thus considered stage IIb lesions. Mc occurrence in adults. It is slow growing and slow to metastasize. Parosteal osteosarcoma can be treated successfully with wide excision of the primary tumor alone. It most commonly occurs in young women over the metaphyseal region, especially the long bones near the knee joint. A conventional parosteal osteosarcoma associated with a high-grade sarcoma (osteosarcoma, fibrosarcoma, MFH) primarily or secondarily after one or more LR (s) with a prognosis similar to the high grade counterpart. Vertebral metastases represent the secondary involvement of the vertebral spine by hematogenously-disseminated metastatic cells. The objective of this study is to describe cases of parosteal Parosteal osteosarcoma (PO) is a rare malignant bone surface tumor Most common surface osteosarcoma Essential features Most commonly occurs in third decade of life with slight female predominance; commonly involves metaphysis of long bones Radiologically, tumor is a lobulated, ossified mass attached to bone surface with radiologic intact periosteum You have never rated this topic. Cancer that spreads (metastasizes). Forty-one cases of parosteal osteosarcoma were reviewed clinically, radiologically and pathologically. A few reported cases had pulmonary metastases before renal involvement. Parosteal Osteosarcoma. Productive osteoblastic osteosarcoma of the left humerus with unilateral eye, cervical muscle, pulmonary, renal, jejunal mesentery, and liver metastases. The most common location is the posterior distal femur. The highest incidence of POS oc- I and II are characterized as low grade, with an average of 16 months2. However, low-grade scintigraphic activity has sometimes been reported in histologically proven enostoses, particularly if the lesion is >1 cm 3. intramedullary osteosarcoma, Ewing's sarcoma, dedifferentiated chondrosarcoma. Parosteal Os-teoma orjuxtacortical osteogenic sarcoma. Heart. Metastasis. parosteal osteosarcoma, low grade I am assuming by now you have been through the procedures. On the other hand, the treatment of low-grade central and parosteal osteosarcomas can rely on surgery alone, provided a complete assessment of their metastatic potential . In only 15% of cases, it can spread to the [] Because parosteal osteosarcoma can dedifferentiate and metastasize and can cause local infiltration and destruction, its presence is an indication Osteosarcoma occurring as a primary tumour in the rib is rare and there are only a few case reports existing in the literature as a primary parosteal osteosarcoma of the ribs [2, 3]. Irrespective of the treatment plan, whether monomodal or multimodal, the principles of surgery remain just the same. Osteosarcoma is a kind of bone cancer which generally starts to develop in the lengthy bones in the legs and arms. Osteosarcoma is a type of bone cancer that most often affects children and teens. PO is most common in young people between the ages of 15 and 30 years old. We present a case o Parosteal osteosarcoma often develops at the posterior surface of the distal femur. However, myocardial metastasis of a parosteal osteosarcoma is an event that was not found in the literature. However, myocardial metastasis of a parosteal osteosarcoma is an event that was not found in the literature. This never bothered me. Additionally, it is uncharacteristic of the disease course of parosteal osteosarcoma to involve multiple local and pulmonary relapses. Partial osteosarcoma is a slowly growing subtype of bone-forming cancer that arises from the outer layer of the periosteum. What is Parosteal Osteosarcoma? J BoneJointSurg(Am]1958:40:1310-1328 7.Scaglietti 0.Calandriello B.Ossifying parosteal sarcoma. It accounts for approximately 15% of all primary bone tumors confirmed at biopsy. Parosteal osteosarcoma (PAOS) is a surface osteosarcoma. Learn more about the subtypes, causes, symptoms, diagnosis, treatment, and prognosis for osteosarcoma. Introduction. Osteosarcoma. The natural history of this disease may extend to five years or longer before metastasis occurs. The differential diagnosis mostly depends on the review of There is usually no technetium-99m MDP uptake, and a normal bone scan can exclude an osteoblastic metastasis or osteosarcoma. Dr. Healey performed the surgery at MSK. There is a metastasis, which presents as a subtle sclerotic lesion in the humerus metaphysis. Periosteal osteosarcoma is also capable of local recurrence and distant metastasis. Osteosarcoma is the most common primary malignant bone tumor in childhood and the second most common primary malignancy of bone in adults (after multiple myeloma). Parosteal OS is a low-grade sarcoma of the bone surface in which hypocellular spindle-cell stroma forms well-differentiated osseous trabeculae. greater metastastatic potential. Introduction. Most common type of juxtacortical/surface osteosarcoma Parosteal Osteosarcoma. Histopathologic diagnosis was parosteal osteosarcoma of the vertebra. Background . Outcomes of dogs with POSA treated with radiation therapy may 2% 22% (624/2898) 2. Primary neoplasm of the bones is relatively uncommon. CONCLUSION:The review leads to the conclusion that the occurrence of metastasis from parosteal osteosarcoma can occur in up to 38% of the cases, in spite of its relatively low aggressiveness. Patient was not a surgical candidate due to extensive metastatic disease, and difficult to access sites of metastasis. Parosteal osteosarcoma, uncommon or relatively unrecog- nized in veterinary medicine: is a distinct type of osteosar- coma. This neoplasm also has been called juxtacortical os- teogenic sarcoma, parosteal osteogenic sarcoma, ossifying par- osteal sarcoma, juxtacortical osteosarcoma, and parosteal os- teoma. Intramedullary well-differentiated osteosarcoma. Parosteal osteosarcoma, uncommon or relatively unrecog- nized in veterinary medicine: is a distinct type of osteosar- coma. This neoplasm also has been called juxtacortical os- teogenic sarcoma, parosteal osteogenic sarcoma, ossifying par- osteal sarcoma, juxtacortical osteosarcoma, and parosteal os- teoma. The manual recognition of osteosarcoma necessitates expert knowledge and is time Parosteal Osteosarcoma. Previous reports of long bone diaphyseal POS are rare. Parosteal Osteosarcoma. Parosteal Osteosarcoma is a malignant, low-grade, osteosarcoma that occurs on the surface of the metaphysis of long bones. The most common location is the posterior distal femur. In the spring of 2020, we, the members of the editorial board of the American Journal of Surgery, committed to using our collective voices to publicly address and call for action against racism and social injustices in our society. Osteosarcoma that spreads most often spreads to the lungs and to other bones. Parosteal osteoid sarcoma, sometimes referred to asjuxtacortical osteogenic sarcoma, is a rare malignant bone tumor which must be differentiated from an osteosarcoma clinically, roentgenologically, and histologically. Pathology in practice. Parosteal osteosarcoma is a rare, low grade sarcoma. 2% (44/2898) 4. Mc site Posterior metaphysis of distal femur. dedifferentiated high grade Parosteal osteosarcoma was rendered. Approximately 80% of tumors are grade 1 and 20% are grade 2.2 Accordingly, it has a well differentiated spindle cell stroma, minimal atypia and a low mitotic rate. What is Parosteal Osteosarcoma? Vertebral tumors may be primary or metastatic. Symptomatic renal metastasis is very rare in osteosarcoma. Dedifferentiated chondrosarcoma. Women > Men. Metastasis mostly occurs with high-grade tumors disseminating to the lungs and other bones. As parosteal osteosarcomas tend to be low-grade lesions, they are usually treated with surgical resection, without chemotherapy or radiation. However, it rarely manifests as a dedifferentiated fashion, which is usually more abrupt and is associated with poorer prognosis. Myocardial. Parosteal Osteosarcoma is a slow-growing, rare bone tumor arising from the cortical surface of the bone. Delayed recurrences (>5 years) of Parosteal osteosarcoma occurs more often in older patients than does conventional high-grade osteosarcoma and is most common in patients aged 20 to 30 years. The tumor originates from the outer fibrous layer of periosteum. What is the stage of this tumor by the Musculoskeletal Tumor Society system? 3, 4 These lesions frequently cause metastatic disease and death, and therefore these patients are usually managed with a combination of surgery and chemotherapy. A long diaphyseal segment of the femur containing the tumor was resected along with a Spread to the pancreas is extremely rare and is undocumented in the low-grade histologic subtype of parosteal osteosarcoma. Metastasis / Myeloma; Aneurysmal Bone Cyst; Chondroblastoma / Chondromyxoid Fibroma; osteosarcoma, Ewings of flat bones: 30 40: reticulum cell sarcoma (Primary histiocytic lymphoma), fibrosarcoma, parosteal osteosarcoma, malignant giant cell tumor, lymphoma: 40 + metastatic carcinoma, multiple myeloma, chondrosarcoma: