Search

Intraosseous schwannoma is extremely rare that it is not often considered among differential diagnosis for an osteolytic lesion, especially in long bones of the extremities. Amounting to less than 0.2% of all primary bone tumours and less than 200 cases reported so far, with only 3 cases involving the humerus, we hereby report the fourth case. In addition to its rarity, this was the only case of an intraosseous schwannoma involving the humerus bone which presented with a pathological fracture in a 45-year-old woman after sustaining a trivial trauma. Radiological examination revealed a geographic type of osteolytic lesion in distal shaft region of the left humerus. Only a histopathological examination helped in revealing and confirming the diagnosis of an intraosseous schwannoma. Treatment of the tumour with complete excision with bone graft reconstruction and osteosynthesis yields good results with very low risk of recurrence.

Background Endoprosthetic replacement of the proximal femur plays a vital role in managing metastatic and primary bone tumours1. Length of stay (LOS) has important resource implications but is driven by patient and disease factors over and above the procedure itself. The aim of this project was to identify factors that drive LOS in patients undergoing proximal femoral replacement (PFR). Methods This was a retrospective analysis of clinical records from a single centre (RNOH). 144 cases were identified over a 4 year-period. These were divided into 3 diagnostic categories: primary bone tumour with chemotherapy, primary bone tumour without chemotherapy and metastatic bone disease. Several factors were considered that could influence the length of stay including age, ASA grade, gender, admission to the high dependency unit (HDU), diagnosis, saving the greater trochanter, pre-operative radiotherapy, admission with a fracture and return to theatre. Results The median LOS for PFR was 15 days, with 79% admitted to HDU. LOS was almost doubled for patients returning to theatre (P = 0.04). Patients with ASA grades of 3 and 4 had a 75% longer LOS compared to those with grade 1. Additionally, a 10-year increase in age was associated with a 6–8% increase in LOS. Incorporating these factors produced a model which explained 27% of the variability of LOS. Conclusion Majority of the variables which were tested were significantly associated with LOS. However, factors other than those in our model drive length of stay. This analysis can support conversations with patients and service planning around LOS.

Aneurysmal bone cysts constitute 1% to 2% of all primary bone tumors. They are rapidly growing benign bone tumors. Nearly 80% of aneurysmal bone cysts occur in the first 20 years of life, and most are primary tumors. Aneurysmal bone cysts are mostly benign, locally aggressive, and highly vascularized tumors. Generally, the period required for postoperative recovery and new bone formation is long. The relapse rate can be up to 50%. Although computed tomo-graphy and magnetic resonance imaging scans are the preferred diagnostic methods, biopsy is the most necessary prerequisite to confirm diagnosis, as aspects of these cysts can show similarity to many other bone lesions. Correct histopathologic diagnosis is important since malignancies may be seen in transplant recipients.

Chondrosarcoma is an uncommon primary bone tumor with an estimated incidence of 0.5 per 100,000 patient-years. Primary chondrosarcoma of the mobile spine and sacrum cumulatively account for less than 20% of all cases, most .commonly causing patients to present with focal pain with or without radiculopathy, or myelopathy secondary to neural element compression. Because of the rarity, patients benefit from multidisciplinary care at academic tertiary-care centers. Current standard-of-care consists of en bloc surgical resection with negative margins; for high grade lesions adjuvant focused radiation with ≥60 gray equivalents is taking an increased role in improving local control. Prognosis is dictated by lesion grade at the time of resection. Several groups have put forth survival calculators and epidemiological evidence suggests prognosis is quite good for lesions receiving R0 resection. Future efforts will be focused on identifying potential chemotherapeutic adjuvants and refining radiation treatments as a means of improving local control.

There are several tumors that do not easily fit into the specific classifications of primary bone tumors. These tumors include tumors of neural, adipocytic, smooth muscle lineage, and some of uncertain lineage. The pathologic features with recent updates of these tumors are discussed here.

Although uncommon in many pathology practices, cartilage-forming tumors represent some of the most frequent primary bone tumors. Diagnosis can be challenging given their variable histologic spectrum and the presence of overlapping morphologic, immunohistochemical, and genetic features between benign and malignant entities, particularly low-grade malignancies. Correlation with clinical findings and radiographic features is crucial for achieving an accurate diagnosis and appropriate clinical management, ranging from observation to excision. Tumors can be characterized broadly by their location in relation to the bone (surface or intramedullary). In specific instances, ancillary testing may help.

Giant cell tumor of bone (GCTB) is a locally aggressive primary bone neoplasm composed by tumoral stromal cells (SCs) and a reactive component that consists of monocytic/histiocytic cells that give rise by fusion to osteoclast-like multinucleated cells. Recently, specific Histone 3.3 mutations have been demonstrated in SCs of GCTB. Many of the pathways related to bone proliferation and regulation depend on the primary cilium, a microtubule-based organelle that protrudes outside the cell and acts as a sensorial antenna. In the present work, we aimed to study the presence and role of primary cilia in GCTB. Ultrastructural, immunohistochemical, and immunofluorescence studies were performed in order to demonstrate, for the first time, that the primary cilium is located in spindle-shaped SCs of GCTB. Moreover, we showed Hedgehog (Hh) signaling pathway activation in these cells. Hence, primary cilia may play a relevant role in GCTB tumorogenesis through Hh signaling activation in SCs. RESEARCH HIGHLIGHTS: Transmission electron microscopy allows describing and differentiating cellular subpopulations in giant cell tumor of bone (GCTB). The primary cilium is present in some tumoral stromal cells of GCTB. Hedgehog signalling is activated in these cells.

Background. Pelvic bone tumors rank sixth among all primary bone tumors (about 16 %) and are one of the complex and little-studied problems of bone oncology, not least due to the complex anatomical structure of the human pelvis. The purpose was to substantiate the effectiveness of computed tomography in the detection of tumor foci in the pelvic bones and to determine the features of the technique of controlled transcutaneous puncture biopsy to verify the nosological form of the tumor. Materials and methods. The analysis of examination of 84 patients with tumor lesions of the pelvic bones was carried out by imaging and performing minimally invasive biopsy under the control of spiral computed tomography. Results. Due to the complexity of the diagnosis of this pathology, 54 (64.3 %) of all patients upon admission to the clinic had a different diagnosis (osteomyelitis, osteochondrosis of the lumbar spine, lumbago or neuralgia, myositis, various traumatic injuries). In 29 (34.5 %) individuals, computed tomography revealed the destruction of the bone tissue of the anterior half of the pelvis, 53 (63.1 %) patients were diagnosed with a tumor in the sacroiliac joint or sacrum, in 2 (2.4 %) cases, traumatic damage to the pelvic bones was found, which was mistaken for a tumor process. Histological verification of the diagnosis was performed by controlled transcutaneous puncture biopsy, the technique of which is carefully described and illustrated. Conclusions. Computed tomography allows you to assess objectively the nature of the tumor, its sizes, the degree of destruction of bone tissue, as well as the germination of the tumor in other anatomical structures, provides a detailed assessment of the effectiveness of treatment in the dynamics. Performing a minimally invasive transcutaneous biopsy under the control of computed tomography in an outpatient setting makes it possible to make quickly a morphological diagnosis and immediately prescribe etiological treatment without losing valuable time., Актуальность. Опухоли костей таза занимают шестое место среди всех первичных опухолей костей (около 16 %) и являются одной из сложных и малоизученных проблем костной онкологии, что не в последнюю очередь связано со сложным анатомическим строением таза человека. Цель: обосновать эффективность применения компьютерной томографии при выявлении опухолевого очага в костях таза; определить особенности методики контролируемой транскутанной пункционной биопсии для верификации нозологической формы опухоли. Материалы и методы. Проведен анализ обследования 84 пациентов с опухолевым поражением костей таза путем визуализации и выполнения малоинвазивной биопсии под контролем спиральной компьютерной томографии. Результаты. Вследствие сложности диагностики данной патологии 54 (64,3 %) из всех пациентов при поступлении в клинику имели другой диагноз (остеомиелит, остеохондроз поясничного отдела позвоночника, люмбаго, невралгия, миозит, различные травматические повреждения). У 29 (34,5 %) пациентов компьютерная томография позволила определить деструкцию костной ткани переднего полукольца таза, у 53 (63,1 %) пациентов диагностирована опухоль в области крестцово-подвздошных сочленений или крестца, в 2 (2,4 %) случаях установлено травматическое повреждение костей таза, которое ошибочно принималось за опухолевый процесс. Гистологическую верификацию диагноза проводили путем контролируемой транскутанной пункционной биопсии, методика которой приведена и проиллюстрирована. Выводы. Компьютерная томография позволяет объективно оценить характер опухоли, ее размеры, степень разрушения костной ткани, а также прорастание опухоли в другие анатомические структуры, обеспечивает детальную оценку эффективности лечения в динамике. Выполнение малоинвазивной транскутанной биопсии под контролем компьютерной томографии в амбулаторных условиях дает возможность быстро поставить морфологический диагноз и сразу назначить этиологическое лечение, не теряя ценного времени., Актуальність. Пухлини кісток таза посідають шосте місце серед усіх первинних пухлин кісток (близько 16 %) та є однією зі складних і маловивчених проблем кісткової онкології, що не в останню чергу пов’язано зі складною анатомічною будовою таза людини. Мета: обґрунтувати ефективність застосування комп’ютерної томографії при виявленні пухлинного вогнища в кістках таза; визначити особливості методики контрольованої транскутанної пункційної біопсії для верифікації нозологічної форми пухлини. Матеріали та методи. Проведено аналіз обстеження 84 пацієнтів із пухлинним ураженням кісток таза шляхом візуалізації та виконання малоінвазивної біопсії під контролем спіральної комп’ютерної томографії. Результати. Внаслідок складності діагностики цієї патології 54 (64,3 %) з усіх пацієнтів при надходженні в клініку мали інший діагноз (остеомієліт, остеохондроз поперекового відділу хребта, люмбаго або невралгія, міозит, різні травматичні ушкодження). У 29 (34,5 %) пацієнтів комп’ютерна томографія дозволила визначити деструкцію кісткової тканини переднього напівкільця таза, у 53 (63,1 %) пацієнтів діагностовано пухлину в ділянці крижово-клубового зчленування або крижа, в 2 (2,4 %) випадках встановлено травматичне ушкодження кісток таза, що помилково вважалося пухлинним процесом. Гістологічну верифікацію діагнозу проводили шляхом контрольованої транскутанної пункційної біопсії, методику якої ретельно описано та проілюстровано. Висновки. Комп’ютерна томографія дозволяє об’єктивно оцінити характер пухлини, її розміри, ступінь руйнування кісткової тканини, а також проростання пухлини в інші анатомічні структури, забезпечує детальну оцінку ефективності лікування в динамиці. Проведення малоінвазивної транскутанної біопсії під контролем комп’ютерної томографії в амбулаторних умовах дає можливість швидко встановити морфологічний діагноз та відразу призначити етіологічне лікування, не втрачаючи цінного часу.

Background An artificial intelligence model that assesses primary bone tumors on radiographs may assist in the diagnostic workflow. Purpose To develop a multitask deep learning (DL) model for simultaneous bounding box placement, segmentation, and classification of primary bone tumors on radiographs. Materials and Methods This retrospective study analyzed bone tumors on radiographs acquired prior to treatment and obtained from patient data from January 2000 to June 2020. Benign or malignant bone tumors were diagnosed in all patients by using the histopathologic findings as the reference standard. By using split-sample validation, 70% of the patients were assigned to the training set, 15% were assigned to the validation set, and 15% were assigned to the test set. The final performance was evaluated on an external test set by using geographic validation, with accuracy, sensitivity, specificity, and 95% CIs being used for classification, the intersection over union (IoU) being used for bounding box placements, and the Dice score being used for segmentations. Results Radiographs from 934 patients (mean age, 33 years ± 19 [standard deviation]; 419 women) were evaluated in the internal data set, which included 667 benign bone tumors and 267 malignant bone tumors. Six hundred fifty-four patients were in the training set, 140 were in the validation set, and 140 were in the test set. One hundred eleven patients were in the external test set. The multitask DL model achieved 80.2% (89 of 111; 95% CI: 72.8, 87.6) accuracy, 62.9% (22 of 35; 95% CI: 47, 79) sensitivity, and 88.2% (67 of 76; CI: 81, 96) specificity in the classification of bone tumors as malignant or benign. The model achieved an IoU of 0.52 ± 0.34 for bounding box placements and a mean Dice score of 0.60 ± 0.37 for segmentations. The model accuracy was higher than that of two radiologic residents (71.2% and 64.9%

Bone metastases are a common source of malignancy in the skeleton and occur much more often than primary bone cancer. Several works were being performed to identify early markers for bone metastasis and novel drug targets to improve patients' quality of life. As some concerns exist with the [18F]sodiumfluoridein positron emission tomography (PET) bone imaging, there has been an increase in the number of targeted radiopharmaceutical markers for bone metastases imaging in its competitor, 68Ga. Since 18F properties are superior to those of 68Ga, there is a distinct motivation for developing 18F radiopharmaceuticals for bone metastases imaging.

Introduction: Temporal bone chondroblastoma is a rare, locally aggressive tumour originating from immature cartilage, which recurs to a high degree. Treatment is surgical. Radiotherapy is reserved for recurrence. We describe a case of a 15-year-old-boy choosing a conservative surgical approach with reconstruction of the posterior canal wall. This study aims to report a rare pediatric case. Methods: A literature review was performed to better understand temporal bone chondroblastomas, to describe their histopathological and radiological characteristics and to establish the optimal surgical and non-surgical treatments. The research of previous published data was done using PubMed with keywords mentioned below. Results: Authors present a case of a 15-year-old boy with hearing impairment and facial nerve palsy. Conservative surgery with reconstruction of the tympanic membrane and posterior wall of the external auditory canal, restoring the hearing has been performed. We did not administer any adjuvant therapies. No sign of recurrence was observed 1 year after primary surgery. Facial nerve function is normal, and hearing is satisfactory. Conclusion: Chondroblastomas account for less than 1% of primary bone tumours. Temporal bone chondroblastoma is rare, locally aggressive, with a high prevalence of recurrence. This study describes specific histopathological and radiological findings, the chosen surgical approach and follow-up to improve the management and the prognosis of patients affected with this particular clinical entity.

Giant cell tumor (GCT) is a locally aggressive benign primary bone tumor accounting for 20% of all the benign primary bone tumors. Peak incidence is between 20 and 45 years with slight female predominance. Distal end of ulna is a rare site for any primary bone tumor, especially 2-4 for giant cell tumors with reported incidence of 0.45 to 3.2% in literature. Considering local aggressive nature and high recurrence, resection is the treatment recommended. In such cases, instability of the ulnar stump and ulnar translation of the carpals are known 3-6 complications causing reduced grip strength. Literature review states, reconstruction with iliac bone graft and stabilization of the ulnar stump with tenodesis using extensor carpi ulnaris. We report a 34 year old female with giant cell tumor of the distal ulna treated by en bloc resection and reconstruction of the distal radio-ulnar joint (DRUJ) and triangular fibrocartilage (TFCC) complex with proximal fibula, palmaris longus graft with augmentation by extensor carpi ulnaris tenodesis and stabilization of the proximal stump with dynamic compression plate. This newer technique of DRUJ and TFCC reconstruction with proximal fibula and palmaris longus graft following en bloc resection of the distal ulna had excellent functional results with no evidence of recurrence after seven months follow-up. This case is presented for its rarity and novelty of the technique used for the anatomical reconstruction.

Objective: The Objective of this study is to analyze the radiological, clinical and functional outcome of patients with acute unstable scaphoid fracture treated with primary bone grafting and K (Kirschner)-wire fixation Methods:Based on inclusion and exclusion criteria , a prospective observational study was carried out on 21 patients with acute unstable scaphoid fracture who had been treated with primary bone grafting and K-wire fixation from November 2017 to March 2020 and were followed up for a minimum of 24 weeks. The average patient age was 26.9 years. The time from injury to treatment averaged 11days. Surgery was done under Bier’s Block using volar approach. Bone graft was harvested from distal Radius. The mean operating time was 24 minutes.Clinical parameters like tenderness, grip strength and Range of Movement (ROM) at wrist was assessed. The functional outcome was evaluated using Modified Mayo wrist score. Bone union was assessed using serial plain radiographs. Results:Union was achieved in all (100%) at 12 weeks. There was no evidence of Avascular necrosis (AVN) or arthrosis at latest follow up. As per Modified Mayo wrist score, there were 15 excellent,03 good and 03 fair results at the final follow-up. Individuals resumed their routine work at 12 weeks and all were comfortable with heavy works/ sports activity by 24 weeks. Conclusion: Primary bone grafting has a definite role in the management of acute unstable scaphoid fracture by which aquicker and higher rate of union isachieved with minimal complications. Open reduction allows thorough assessment of fracture for better anatomic reduction. Although the type of fixation device hardly contributes for quicker and higher union, but then the use of K-wire for fixation is the only viable option for smaller bony fragments and is more forgiving in terms of its positioning. It has an added advantage in terms of requirement of minimal inventory and thus is a cost-effective modality. This procedure also confirms that the patients could get back to their work earlier hence decreasing economic burden.

Purpose: Reconstruction of the proximal femur after tumour resection can be performed with proximal femoral endopros-theses (PFE). Many studies have reported that bipolar hemiarthroplasty (BHA) reduce the risk of dislocation after oncological resections. However, progressive cotyloiditis which might require acetabular resurfacing (total hip arthroplasty [THA]) has been reported. The aim of this study is to compare the results of BHA and THA after proximal femur resection. Materials and Methods: A total of 104 consecutive patients affected by primary (n=52) and metastatic (n=52) bone tumours were included. Ninety patients underwent BHA and 14 patients underwent THA. Complications were recorded and classified according to the Henderson classification. At final follow-up, patients with the implant in site were functionally evaluated with modified Harris hip score (HHS). Results: The mean follow-up was 50 months (range, 2-171 months). Twenty-four (23.1%) patients developed major complications. Eleven (12.2%) BHA required acetabular resurfacing. Patients affected by primary bone tumours showed an increased risk of THA conversion (P=0.042). A reduced risk was observed in patients younger than 35 years (P=0.043) and in those older than 65 years (P=0.033). Dislocation occurred in four case (3.8%), in particular after THA (P=0.021). At final follow-up, 93 patients had the prosthesis in site (80 BHA and 13 THA). Mean postoperative HHS was 70 (range, 30-90). Conclusion: The risk of dislocation is lower for bipolar endoprosthesis compared to THA. However cotyloiditis and acetabular resurfacing might occurred.

Osteosarcoma is the most common malignant primary bone tumor that occurs most frequently in the second decade of life but rarely in patients over 40 years of age. The most common primary sites of osteosarcoma are the distal femur followed by proximal tibia and proximal humerus, and involvement of the wrist is extremely rare. Moreover, dedifferentiated osteosarcoma is also a rare condition that progresses to high-grade osteosarcoma from low-grade osteosarcoma, usually central low-grade osteosarcoma or parosteal osteosarcoma that bears MDM2 and/or CDK4 gene amplifications. We herein report an extremely rare case of dedifferentiated osteosarcoma arising in the distal ulna of an adult over 40 years of age. The patient was a 46-year-old man with a 2-month history of pain in his left swollen wrist. The initial radiological findings suggested a benign bone tumor in the distal ulna, and the lesion was marginally excised at the nearby hospital. Although the pathological diagnosis at the nearby hospital suggested a benign cartilaginous tumor, the tumor recurred in an aggressive manner 8 months after the initial surgery. The patient was referred to our hospital, and an incisional biopsy showed a high-grade osteosarcoma. The primary tumor was retrospectively re-evaluated at our hospital and diagnosed as low-grade osteosarcoma. Since neoadjuvant chemotherapy failed to shrink the tumor, the patient had to undergo below the elbow amputation to cure the disease. Although the tumor was negative for MDM2 nor CDK4, the definitive diagnosis of dedifferentiated osteosarcoma was made according to the clinical course and the histological findings. Lung metastases were found 10 months after the amputation, which were successfully treated by neoadjuvant chemotherapy and surgery. The patient has been doing well with no evidence of disease for 1 year and 6 months. Surprisingly, the literature review revealed that many low-grade osteosarcomas of the distal ulna progressed to high-grade dedifferentiated osteosarcomas. One should bear in mind that the diagnosis and treatment for bone-forming tumors of the distal ulna should be made very carefully because, although rare, it is possible that the tumor may initially appear as a benign or low-grade malignant tumor and may progress to high-grade osteosarcoma.

The number of patients with bone metastasis increases as medical management and surgery improve the overall survival of patients with cancer. Bone metastasis can cause skeletal complications, including bone pain, pathological fractures, spinal cord or nerve root compression, and hypercalcemia. Before initiation of treatment for bone metastasis, it is important to exclude primary bone malignancy, which would require a completely different therapeutic approach. It is essential to select surgical methods considering the patient’s prognosis, quality of life, postoperative function, and risk of postoperative complications. Therefore, bone metastasis treatment requires a multidisciplinary team approach, including radiologists, oncologists, and orthopedic surgeons. Recently, many novel palliative treatment options have emerged for bone metastases, such as stereotactic body radiation therapy, radiopharmaceuticals, vertebroplasty, minimally invasive spine stabilization with percutaneous pedicle screws, acetabuloplasty, embolization, thermal ablation techniques, electrochemotherapy, and high-intensity focused ultrasound. These techniques are beneficial for patients who may not benefit from surgery or radiotherapy.

The paper studies the effect of the RVI biocomposite material belonging to the group of osteoplastic biocomposite materials, the RV-2 immunomodulator – a synthetic dipeptide inducing an immunocorrective effect, and combinations of these drugs on the reparative histogenesis of bone tissue in femoral fractures in rats. It was found that the remodeling of the primary bone callus into the secondary one in the fracture of the studied animals was of a diverse nature. This process was the most pronounced in the group where the components were used in complex, i.e. the bone defect was filled with RVI during the surgery, as well as RV-2 was injected intramuscularly to rats at a dose of 10 mcg per 1 kg of live weight for five days, starting immediately after the surgery. Well-formed coarse-fibrous connective tissue callus was recorded in animals of this group. The connective tissue was stained more intensely which indicates a denser arrangement of fibers in the callus. Focal cartilage tissue spanning bone fragments was observed within the callus. At the periphery of the site the cartilaginous callus was subjected to endochondral ossification with replacement by coarse-fibrous trabeculae with elements of lamellar bone tissue having haversian canals in the center. The inter-girdle spaces were filled with elements of the myeloid bone marrow in the forming bone tissue. Markedly proliferated osteoblasts were visible in the cambial layer of the periosteum. The bone tissue ratio increased up to (60.21 ± 2.62)%, which significantly exceeded the same indicator in the control group and in all experimental groups. The low content of connective tissue and the high ratio of bone tissue indicated more active osteogenesis processes and reparative regeneration in comparison with other groups.

Giant cell tumor of bone (GCTB) is a locally aggressive and rarely metastasizing tumor. GCTB is characterized by the presence of unique giant cells and a recurrent mutation in the histone tail of the histone variant H3.3, which is encoded by H3F3A on chromosome 1. GCTB accounts for ~ 5% of primary bone tumors. Although GCTB exhibits an indolent course, it has the potential to develop aggressive behaviors associated with local recurrence and distant metastasis. Currently, complete surgical resection is the only curative treatment, and novel therapeutic strategies are required. Patient-derived cancer cell lines are critical tools for basic and pre-clinical research. However, only a few GCTB cell lines have been reported, and none of them are available from public cell banks. Therefore, we aimed to establish novel GCTB cell lines in the present study. Using curetted tumor tissues of GCTB, we established two cell lines and named them NCC-GCTB2-C1 and NCC-GCTB3-C1. These cells harbored a typical mutation in histones and exhibited slow but constant growth, formed spheroids, and had invasive capabilities. We demonstrated the utility of these cell lines for high-throughput drug screening using 214 anticancer agents. We concluded that NCC-GCTB2-C1 and NCC-GCTB3-C1 cell lines were useful for the in vitro study of GCTB.

The structural changes in the tissues of the osteochondral junction are a topic of interest, especially considering how bone changes are involved in the initiation and progression of osteoarthritis (OA). Our research group has previously demonstrated that at the cement line boundary between the zone of calcified cartilage (ZCC) and the subchondral bone, in mature bovine patellae with early OA, there are numerous bone spicules that have emerged from the underlying bone. These spicules contain a central vascular canal and a bone cuff. In this study, we use high-resolution differential interference contrast optical microscopy and scanning electron microscopy to compare the cartilage-bone junction of three groups of mature bovine patellae showing healthy to mild to moderately degenerate cartilage. The ZCC and bone junction was carefully examined to estimate the frequency of marrow spaces, bone spicules and fully formed bone bulges. The results reveal that bone spicules are associated with all grades of cartilage tissue studied, with the most occurring in the intermediate stages of tissue health. The micro and ultrastructure of the bone spicule are consistent with that of an osteon, especially those found in compression zones in long bones. Also considering the coexistence of marrow spaces and fully formed bone, this study suggests that these bone spicules arise similar to the formation of osteons in the bone remodelling process. The significance of this conclusion is in the way researchers approach the bone formation issue in the early degenerative joint. Instead of endochondral ossification, we propose that bone formation in OA is more akin to a combination of primary bone remodelling and de novo bone formation.

Toxoplasma gondii (T. gondii) is an intracellular parasite that infects humans, and seroprevalence of its infection varies from about 10 to 80 percent in different countries with a higher prevalence in warmer and humid regions. In this study, the rate of acute and chronic toxoplasmosis in patients with benign or malignant bone tumours was investigated. Fifty-three patients who suffered from various bone tumours, as well as sixty-five healthy controls with an unknown sero-logical profile for anti-Toxoplasma antibodies, were enrolled in this cross-sectional study. Anti-Toxoplasma antibodies were detected in serum samples using enzyme-linked immunosorbent assay (ELISA) and blood samples of them were used for real-time PCR. Thirty-two (60.32%) and twenty-one (39.63%) of patients had malignant tumours and benign tumours, respectively. The results showed a higher and significant seropositivity rate of IgM antibodies in primary bone tumour patients compared to the control group and Toxoplasma DNA became positive in 18.86% of patients with primary bone tumours and 6.15% of controls. Surprisingly, the high presence of parasite DNA was detected in patients with malignant tumours. The seroprevalence of T. gondii IgM antibodies and DNA positivity among the cancer patients were significantly higher than healthy individuals. Also, chronic toxoplasmosis (it was shown with IgG positive) appears to be more common in people with benign cancers than malignancies. The study showed a relatively high seroprevalence of anti-T. gondii antibodies in patients with primary bone cancer. However, the considerable rate of positive blood samples for the presence of parasite’s DNA should not be ignored. A key to the effective management of diseases in immunosuppressed individuals is prompt and accurate diagnosis of toxoplasmosis. Moreover, it seems that PCR tests may be more reliable than serological methods and it could be considered as a precise method for diagnosis of acute toxoplasmosis.

INTRODUCTION Segmental skeletal defects are very difficult to treat. The current options are lengthy procedures, require more than one surgery and plagued with many complications. The aim of this study is to assess the results of bone graft in surgicel as a synthetic membrane for reconstruction of segmental skeletal defects in one stage surgery. METHODS Fourteen patients with segmental skeletal defects were included in the study. The ages ranged from 20 to 54 years with an average of 32 years. The defects were due to high energy trauma in all cases. The size of the defects ranged from 5 to 12 cm with an average of 7 cm. They were located in the distal femur in 11 cases and middle third of the femur in three cases. All cases were treated by the synthetic membrane technique in one stage surgery. Surgicel was used as a synthetic membrane and both the fibular strut autograft and morselized allograft were used to fill the defects in all patients. RESULTS All cases healed without additional procedures after the index surgery except in three cases. The time-to-bone union ranged from six to 13 months with an average of eight months. After physiotherapy all patients regained good range of knee movements except two cases. The complications included deep wound infection in two cases, nonunion of the graft in one case and joint stiffness in two cases. CONCLUSION Primary bone graft in surgicel as a synthetic membrane is a good technique for management of post-traumatic bone defects. It reduces the time and number of surgeries required for reconstruction of this difficult problem.

Osteoblastoma is a rare benign osseous neoplasm that accounts for 1%-3% of all primary bone tumors. Osteoblastomas can involve any part of the skeleton, but mainly occurs in the spine and other long bones, rarely in extra-skeletal areas. Extra-skeletal osteoblastomas arise from tissues outside of the bone, and only a few cases have been reported previously. To our knowledge, only one case of osteoblastoma in the breast has been described in the English literature. Here, we report another case of a breast osteoblastoma in a middle-aged woman, which was initially detected by ultrasound examination and digital mammography, and then was confirmed by histopathology. In this report, the imaging features and differential diagnosis of breast osteoblastoma are discussed.

Background Although rare, pathological fractures may occur in primary bone sarcomas. There have been studies reporting that such patients have a poorer prognosis than those without a pathological fracture. This study investigates the impact of pathological fractures on surgery, morbidity, functional and oncological outcomes in patients with primary bone sarcomas. Patients and methods A retrospective analysis of 568 patients with primary bone sarcomas, treated between 2005 and 2019, was performed. The study included 41 patients with a pathological fracture and 51 control patients who did not have a pathological fracture. A multivariate Cox regression analysis was used to investigate the impact of pathological fractures and further independent variables on amount of intraoperative bleeding, duration of surgery, number of muscles and major neurovascular structures included in resection, tumor volume, surgical volume, Musculoskeletal Tumor Society (MSTS) functional score, postoperative complication rate, and local recurrence, distant metastasis, and survival rates. Results There were 36 (39%) female and 56 (61%) male patients. No statistically significant difference was noted in tumor volume, tumor/surgical volume percentage, number of major neurovascular structures included in resection, postoperative complication rate, and local recurrence, distant metastasis, and survival rates between the two groups (p > 0.05). A significantly higher amount of intraoperative bleeding and number of transfused blood components, a longer duration of surgery, and a higher amount surgical volume and number of resected muscles were detected in Group 1 compared to Group 2 (p=0.001, p=0.002, p=0.007, p=0.007, p < 0.001, respectively). The MSTS functional scores were lower in patients with a pathological fracture than in those without a pathological fracture (p=0.001). Conclusion We conclude that a pathological fracture through a primary bone sarcoma has no adverse effect on prognostic factors such as local recurrence, distant metastasis, and survival. However, pathological fractures increase the amount of intraoperative bleeding and surgical volume and result in a longer surgery, in addition to decreased functional outcomes.

Chondromyxoid fibroma is rare cartilaginous tumor, accounting for 0.5% of all primary bone tumors and 2% of benign bone tumors. Areas of aneurysmal bone cysts (ABC) may be found within CMF in 8.6% of cases. A 20-year-old man presents pain due to a mass on iliopubic ramus that was diagnosed as an aneurysmal bone cyst arising from a chondromyxoid fibroma. This case confirms the rare association between aneurysmal bone cyst and chondromyxoid fibroma. Although aneurysmal bone cyst is more frequently associated with highly vascularized tumors, it is important to consider the diagnosis in the presence of chondromyxoid fibroma. Keywords: Chondromyxoid fibroma; scecondary aneurysmal bone cyst; iliopubic ramus

Aim The biological reconstruction of the knee with osteoarticular allografts and resection arthrodesis have been reported but there has not yet been a direct comparison between both these procedures. This study aimed to identify the prognostic factors that influence failure of biological reconstruction and compared the results between both procedures. Methods Between 1994 and 2017, we performed 92 limb-sparing procedures using resection arthrodesis (n = 53) and osteoarticular allograft reconstruction (n = 39) for the management of primary bone tumors around the knee. The minimum follow-up time was 2 years in both groups. Results The failure rate of reconstruction in the osteoarticular allograft and resection arthrodesis group was 48.7% and 39.6%, respectively (p = 0.75). The mean MSTS score in the osteoarticular allograft and resection arthrodesis group was 23.7 and 21.8, respectively (p = 0.01). The significant risk factor for failure after biological reconstruction was the administration of chemotherapy (p = 0.001; HR = 3.39; 95% CI, 1.60-7.17). Conclusion Patients who underwent osteoarticular allograft had a better functional outcome than those who underwent resection arthrodesis reconstruction, but clinical outcomes between the groups were comparable. Chemotherapy is a significant adverse prognostic factor for failure of biological reconstruction.

Objectives: Bone tumors are uncommon. Nevertheless, bone is a common site for metastasis. Due to limited data regarding bone tumors in Jordan, this study aims to understand better bone tumor epidemiology and distribution in the Jordanian population. Methods: A part of a retrospective, single-center study, all biopsy reports confirming the diagnosis of a bone tumor between January 2017 and December 2019 were abstracted from Princess Iman Research Center records. The patients’ age, gender, anatomical location, and histopathological type of the tumors were obtained and analyzed. Results: Two hundred eighty-four diagnostic and excisional biopsies were reviewed. Most of the patients (60.2%) were males. The mean age for the patients was 26.74(±16.29) years. Malignant bone tumors were diagnosed in 15.5%. The femur was the most common site of biopsy diagnosed tumor followed by the tibia. Osteochondroma was the most commonly diagnosed benign tumor and accounted for 39.4%, followed by aneurysmal bone cysts (14.8%), and enchondroma (10.2%). The metastatic bone tumors were the most frequent malignant bone pathology (6.7%), while osteosarcoma was the most common primary sarcoma, diagnosed in 5.6% of the sample. Increasing age, pelvic, and spine location of bone tumors were found to be significantly associated with malignancy. Conclusion: In our 284 samples, osteochondromas were the most commonly diagnosed tumors (39.4%), followed by aneurysmal bone cysts (14.8%), and enchondromas (10.2%). Metastatic tumors were the most common malignant bone pathologies, while osteosarcomas were the most common primary bone sarcomas. Femur and tibia were the most common tumor-located sites. Breast and lung deposition were the most common metastasis primaries. Additionally, increasing age, pelvic, and spine-located bone tumors were significantly associated with malignancy.

Background: Distal tibial primary bone tumors are rare, and options for limb salvage surgery are limited and challenging. Importantly, local control has shown to be crucial and necessary for cure, and radical surgery is one of the most important components of therapy for some bone sarcomas. We investigated the feasibility and functional and oncological outcomes of distal tibial reconstruction using endoprosthesis in children with malignant bone tumors. Methods: Fourteen patients (median age 13.6 years) with primary bone tumors (4 Ewing sarcoma [ES], 10 osteosarcoma) of the distal tibiae were treated during 2013-2019. All patients had reconstruction using a modular (13 patients) or expandable custom-made titanium bone replacement system (1 patient). All patients received chemotherapy before and after surgery. Results: Twelve patients (85.7%) are alive with a median follow-up 20 months from diagnosis. Five-year estimates of event-free survival and overall survival were 60.6% and 76.4%, respectively. Three patients had postoperative complications requiring second surgery. Maximum dorsiflexion and plantar flexion of the foot were 20 degrees (range 0-20 degrees) and 20 degrees (range 5-20 degrees), respectively. Conclusion: For select distal tibial sarcomas, after neoadjuvant chemotherapy pretreatment and radical resection, reconstruction using an endoprosthesis as a radical surgery provides an option was associated with a low rate of short-term local complications and relatively good early function. Level of Evidence: Level IV, therapeutic study.

Background To date, no standard treatments for primary bone sarcomas other than those for osteosarcoma, Ewing sarcoma and chondrosarcoma have been developed. Methods The clinical characteristics and prognostic factors of 330 patients with primary bone sarcomas other than osteosarcoma, Ewing sarcoma and chondrosarcoma, listed in a nationwide tumour registry (Bone and Soft Tissue Tumor Registry in Japan) were investigated. The effects of adjuvant chemotherapy were determined by comparing the outcomes of patients with non-metastatic bone tumours who received surgery plus chemotherapy with those of patients who underwent surgery alone. Results The most common diagnosis was undifferentiated high-grade pleomorphic sarcoma. Axial site tumours (47.8%) and distant metastases at presentation (24.5%) were frequent. The 5-year overall and progression-free survival rates were 44.9 and 39.9%, respectively. Prognostic factor analysis identified surgery as an independent predictor of overall survival, and distant metastases at presentation was significant and independent predictor of both overall and progression-free survival. No significant difference in outcome was observed between patients treated with surgery alone and those treated with surgery plus chemotherapy (P = 0.71). Conclusions Patients with bone sarcomas other than osteosarcoma, Ewing sarcoma and chondrosarcoma without metastasis at presentation have a relatively good prognosis with definitive surgery; however, the benefit of adjuvant chemotherapy is unclear.

Background Joint-sparing resections (JSR) of the proximal femur allow for preservation of the proximal femoral growth plate and native hip joint, but whether this offers fewer complications or better function and longevity of the reconstruction remains unknown. In this study, we compared the functional outcomes of pediatric patients with bone sarcomas undergoing JSR of the proximal femur with intercalary allograft (ICA) reconstruction to those undergoing proximal femoral resections (PFR) with allograft-prosthetic composite (APC) reconstructions. Methods We retrospectively reviewed all patients undergoing JSR with ICA reconstruction and PFR with APC reconstructions between 1995 and 2013 at a tertiary pediatric referral center. Primary outcomes included major and minor complications and secondary outcomes included the need for a secondary procedure, presence of local or distant relapse, survival status, and the presence of pain and ambulatory status (limp, assistive device, highest level of function). We assessed differences in outcomes using the Fisher exact and Wilcoxon rank-sum tests. Results Eight patients underwent a JSR and ICA reconstruction, while 7 patients underwent a PFR with APC reconstruction. Median patient follow-up was 60.4 months (interquartile range: 36.8 to 112.9) Patients undergoing JSR and ICA reconstruction were younger than patients undergoing PFR with APC reconstruction (7.7 vs. 11.7 y, P=0.043); however, we found no other statistically significant differences in patient demographics. There were no statistically significant differences in primary or secondary outcomes between the study groups; however, patients who underwent JSR with ICA had more major complications (62.5% vs. 42.9%, P=0.29) and a lower rate of minor complications (25% vs. 28.6%, P=0.22). Conclusion Treatment of proximal femoral bone sarcomas in pediatric and adolescent patients remains a challenging enterprise. JSR with ICA reconstruction in the proximal femur, when feasible, may provide a similar function and risk of intermediate-term major and minor complications when compared with PFR with APC reconstruction. Further long-term studies are required to determine the impact of the native femoral head retention with respect to revision rates. Level of evidence Level III, retrospective comparative study.

Introduction: A worrying increase in the number of bone tumors that appear at younger ages justifies the efforts aimed at optimizing perioperative management practices in orthopedic tumor surgery. Pain control is critical in the prognosis and postoperative outcome of these procedures. Material and methods: Our study included a group of 11 patients diagnosed with bone malignancies. These patients were hospitalized in the Orthopedic Clinic of the University Emergency Hospital Bucharest. Under our supervision, they underwent surgical treatment of the tumor under combined general anesthesia and epidural anesthesia for the pelvic limb, and general anesthesia only for the upper limb. We performed perioperative pain management with multimodal analgesia (continuous epidural analgesia with ropivacaine 0,2% and fentanyl 2 mcg/ml in association with systemic analgesics). Following this procedure, we measured the intensity of the postoperative pain at intervals of 48 hours and one week after surgery and compared with preoperative pain intensity using the visual analogue pain scale (VAS). Results: Multimodal analgesia (epidural analgesia associated with systemic analgesics – paracetamol, COX2 inhibitor, gabapentinoids) was performed well in the postoperative pain of the tumor prosthesis, with a significant decrease in VAS from a mean value of 7.63 preoperatively to an average of 3 in the first 48 hours postoperatively. After the removal of the epidural catheter, which also coincided with patient mobilization, the level of pain registered a slight increase to a mean value of 3.23. Conclusions: Multimodal analgesia is currently considered the gold standard in perioperative pain management. The use of multimodal analgesia during perioperative period in patients with bone tumors has been shown to decrease the length of hospital stay, improve surgical outcome, reduce the number of systemic complications, and improve the long-term prognosis of the patient. Efficacy of analgesia correlates with tumor site and vascularization.

Benign primary bone tumours are rare, occurring most commonly in skeletally immature patients, arising from cartilage or bone. The commonest locations are the distal femur, proximal tibia and proximal humerus. They present with pain, swelling or pathological fracture. Diagnosis is by plain x-rays, MRI scans and a core needle biopsy if indicated. More aggressive tumours may appear radiologically to be similar to malignant tumours. Treatment depends on the anatomical location, symptoms, the natural history of the tumour and the morbidity of treatment and in most cases involves either simple excision or curettage although occasionally it is necessary to perform a complete excision using the same principles as for malignant tumours.

Objectives: We aimed to investigate the radiological, biomechanical, histopathological, histomorphometric, and immunohistochemical effects of different doses of vardenafil on fracture healing. Materials and methods: Fifty-one rats were divided into three groups. Group V5 was given 5 mg/kg/day of vardenafil; Group V10 was given 10 mg/kg/day of vardenafil; and the control group was given the same volume of saline. Six rats from each group were sacrificed on Day 14 (early period) and the remaining rats were sacrificed on Day 42 (late period). Callus/femoral volume and bone mineral density were measured using micro- computed tomography. Five femurs from each group in the late period were examined by biomechanical tests. In addition to the histopathological and histomorphometric evaluations, immunohistochemical analyses were performed to examine the levels of inducible nitric oxide synthase (iNOS), transforming growth factor-3 (TGF-β3), and nuclear factor kappa B (NF-κB) proteins. Results: Both doses of vardenafil increased primary bone volume and maximal bone fracture strength in late period, compared to the control group (p^lt;0.05). Histological healing scores of vardenafil groups were significantly higher in early period (p Conclusion: During the first period of fracture healing process in which vasodilation is mostly required with increasing inflammation, vardenafil has ameliorating effects on the bone union and supports fracture healing.

Bone tumours are rare; primary bone sarcomas should be referred to specialist centres for investigation and management. Accurate diagnosis is usually achieved with history, clinical examination and plain radiographs. For bone tumours the patient's age, the site, size and location within the bone, margins, matrix and presence of periosteal reaction or soft-tissue extension all determine biological activity and the diagnosis. Other imaging modalities may supplement the radiological diagnosis but are of greater use in local and distal staging of the disease, surgical planning and surveillance. Biopsies are frequently guided by cross-sectional imaging but should be carefully planned in conjunction with the surgeon performing the definitive procedure. New radiological modalities are increasingly being used to support and supplement the management of musculoskeletal oncology patients.

Giant cell tumors (GCT) of bone are a benign aggressive tumor with features of frequent local recurrence. It has the potential for metastasis and malignant transformation. GCT of bone represents about 4–9.5% of primary bone tumors. Metachronous GCT happen in less than 1% while metastatic spread in these lesions is very uncommon. Furthermore, reports of multicentric metachronous GCT are very rare in literature. We present a case of a 35-year-old male patient, who suffered from multicentric metachronous GCT, which involved the radius, humerus, femur, and pelvic with pulmonary metastasis. Local control by multiple resections of the tumor and chemotherapy for pulmonary metastases was able to control the disease with long-term survival and good functional outcome. These tumors had a typical radiological appearance and the diagnosis was confirmed on histopathology. Long follow-up needed in this case in view the illness occurs for long period.

BACKGROUND Primary bone lymphoma (PBL) is an uncommon extranodal disease that represents approximately 1%-3% of lymphomas. Anaplastic lymphoma kinase (ALK) positive anaplastic large-cell lymphoma (ALCL) is an extremely rare type of PBL. The aim of this report is describe the symptoms, diagnosis, and treatment of primary bone ALK-positive ALCL. CASE SUMMARY A 66-year-old man presented to our hospital with neck and shoulder pain and intermittent fever that lasted for 1 mo. After extensive evaluation, positron emission tomography-computed tomography (CT) examination showed multiple osteolytic bone lesions without other sites lesions. CT-guided biopsy of the T10 vertebral body was performed, and the pathology results showed that neoplastic cells were positive for ALK-1, CD30, and CD3. A diagnosis of primary bone ALK positive ALCL was ultimately made. The patient was in partial response after four cycle soft cyclophosphamide, doxorubicin, vincristine, and prednisone chemotherapy, and we planned to repeat the biopsy and radiological examination after completion of the fifth cycle of therapy. CONCLUSION Primary bone ALK positive ALCL is a rare disease and physicians should keep in mind that ALCL can present with isolated osseous involvement without nodal involvement, and lymphoma should be considered in the differential diagnosis of primary bone lesions.

Osteoporosis is one of the most common metabolic bone diseases affecting millions of people. We previously found that harmine prevents bone loss in ovariectomized mice via increasing preosteoclast platelet‐derived growth factor‐BB (PDGF‐BB) production and type H vessel formation. However, the molecular mechanisms by which harmine promotes preosteoclast PDGF‐BB generation are still unclear. In this study, we revealed that inhibitor of DNA binding‐2 (Id2) and activator protein‐1 (AP‐1) were important factors implicated in harmine‐enhanced preosteoclast PDGF‐BB production. Exposure of RANKL‐induced Primary bone marrow macrophages (BMMs), isolated from tibiae and femora of mice, to harmine increased the protein levels of Id2 and AP‐1. Knockdown of Id2 by Id2‐siRNA reduced the number of preosteoclasts as well as secretion of PDGF‐BB in RANKL‐stimulated BMMs administrated with harmine. Inhibition of c‐Fos or c‐Jun (components of AP‐1) both reversed the stimulatory effect of harmine on preosteoclast PDGF‐BB production. Dual‐luciferase reporter assay analyses determined that PDGF‐BB was the direct target of AP‐1 which was up‐regulated by harmine treatment. In conclusion, our data demonstrated a novel mechanism involving in the production of PDGF‐BB increased by harmine, which may provide potential therapeutic targets for bone loss diseases.

Background . Giant cell tumor of bone (GCTB) is a common benign lesion accounting for 4–9.5 % of all primary bone tumors. Although surgery is considered the method of choice in the treatment of GCT, however, denosumab, a genetically engineered drug with a novel mechanism of action, has been recently used to treat GCTB. Histological examination of a surgical specimen is undoubtedly the most objective method for assessing the effectiveness of the treatment. However, in some cases it is necessary to assess the effectiveness of conservative therapy at the stages of its implementation. The purpose of the study was to compare CT-densitometry findings with histological findings in GCTB patients treated with denosumab. Material and Methods. The study included 30 patients aged from 28 to 59 years with histologically verified GCTB, who received targeted therapy with denosumab followed by surgery. The changes in tumor structure during denosumab therapy and surgical specimens of the tumor were assessed. Results. The relationship between the CT-densitometry findings and histopathological findings of surgical specimens was revealed in GCTB patients treated with denosumab. Conclusion. CT-densitometry findings were shown can be used to predict pathological response of the tumor to denosumab treatment.

Purpose This study assessed implant survival and dislocation following proximal femur tumor endoprosthetic replacement. Methods Thirty-eight procedures were performed between 2005 and 2019. The cumulative incidence of implant revision was calculated with death as a competing risk. Results The majority of endoprostheses were bipolar hemiarthroplasty (n = 33, 86.8%). The cumulative incidence of revision was 14.6% (95% CI, 3.2%–34.1%) at five years. Dislocation occurred in 7.9% (n = 3) of hips at a mean (SD) 44 ± 35.2 days. Conclusions Proximal femur tumor endoprosthetic replacement is a durable option that tends to outlive patients. Strict postoperative bracing may lower dislocation rates. Level of evidence III. Retrospective Study.

BackgroundThe calcar femorale was identified long ago. However, our current understanding of the calcar is insufficient, and its related concepts are sometimes confused. The calcar femoral is an important anatomical structure of the proximal femur, and its function can be overlooked. In trauma, tumors, or other diseases, the calcar femorale can be destroyed or changed pathologically. As a result, the mechanical structure of the proximal femur becomes destroyed, causing pathological fractures. How to address the destruction of the calcar femorale or the damage to the calcar femorale is discussed in this article.Main textDestruction of the calcar femorale is accompanied by many conditions, including trauma, tumors, and other diseases. The types of hip fractures caused by trauma include femoral neck fractures and intertrochanteric fractures. Dynamic hip screws, proximal femoral nail anti-rotation, and multiple parallel cannulate pins can be used in different conditions. When metastatic and primary bone tumors involve the calcar femorale, endoprostheses are widely used. Other diseases, such as fibrous dysplasia and aneurysmal bone cyst are treated differently.ConclusionsThe calcar femorale can redistribute stresses and the destruction of the calcar femorale can lead to an increase in posterior medial stress. Many factors need to be considered when deciding whether to reconstruct the calcar femorale. Effective treatment strategies for managing the destruction of calcar femorale will need first establishing the precise mechanism of the destruction of the calcar and then designing therapies towards these mechanisms. Further investigation to the calcar needs to be carried out.

Chondromyxoid fibroma; a rarely found tumor, contributing

Immunoglobulin G4-related sclerosing disease (IgG4RD) is an emerging immune-mediated fibro-inflammatory disorder which can involve any organ. We describe the first IgG4-RD spondylitis treated with total en-bloc spondylectomy (TES). A 55-year-old man presented with back pain. Magnetic resonance imaging (MRI) of the thoracic spine revealed a pathologic compression fracture on T11 vertebral body and both pedicles suggestive of primary bone tumor or bone metastasis. We conducted TES of T11, because we could not exclude the possibility of primary bone tumor including giant cell tumor. Immunohistochemical examination of the pathology specimens from pleura around the pedicle demonstrated diffuse infiltration of IgG4-bearing plasma cells. Six weeks later from the surgery, a delayed serologic test was done and his serum IgG4 concentration was 45 mg/dL. The final diagnosis was probable IgG4RD on the basis of serological, imaging, histopathological findings. After 6 weeks of oral prednisolone treatment, patient's back pain improved dramatically. IgG4RD is very rare systemic disease and its paraspinal soft tissue like pleura involvement with vertebra body invasion was absent until now. Our experience indicated that surrounding soft tissue biopsy would be helpful when a percutaneous vertebra bone biopsy mismatched with the image studies, even though vertebra body was main pathological lesion considering the possibility of IgG4RD.

The radiographic appearance of primary bone tumors is important for initial diagnosis and often augments histopathological analysis. The original grading system relied on the radiographic analysis of the margin of the lesions to determine tumor aggression, which often corresponds with malignant potential. The recently developed, modified Lodwick-Madewell grading system also incorporates the appearance of lesion margins on radiographs but also considers the change in margins on serial radiographs and includes a category for clinically suspected, radiographically occult, aggressive lesions. This article reviews the prior and modified grading systems, and the concepts necessary for proper interpretation of the initial appearance of bone tumors which often determines the radiologist's recommendation for biopsy or follow-up imaging.

Bone sarcoidosis is usually considered a rare manifestation of multisystemic sarcoidosis. With the growing use of more sensitive imaging techniques, such as 18F-FDG PET, the detection rate of bone involvement seems to be increasing. We describe the case of a woman presenting with fatigue and general malaise having multiple bone lesions on 18F-FDG PET. A broad range of differential diagnoses was considered, including malignancy, infections, metabolic diseases and primary bone tumours, which may have delayed the diagnosis. Diagnostic work-up eventually led to an anatomopathological diagnosis of bone sarcoidosis. Immunosuppressive therapy is often necessary since sarcoid bone lesions - even asymptomatic - generally appear in more extensive forms of the disease with other organ involvement.

Osteosarcoma is the most common primary bone tumor and usually involves the long bones. Osteosarcoma of the skull, on the other hand, is relatively rare. Here, we present a 29-year-old man with a growing mass in the skull he first noticed after a fall while skateboarding. The initial clinical diagnosis was hematoma. While undergoing an evacuation surgery for a hematoma, a suspicious mass was detected which was biopsied. Histopathological evaluation showed high-grade osteosarcoma. The patient was referred to our hospital where he underwent definitive resection followed by adjuvant chemotherapy. His course was complicated by wound infection. Even though osteosarcoma of the skull is a rare finding, it should be suspected in a patient with a skull mass, and the history of prior head trauma does not exclude the diagnosis.

Lytic lesions in adult spine are a common manifestation of aggressive disease such as primary bone tumor, metastasis, myeloma, or infectious pathology. Xanthoma arising in the spine with purely intraosseous component is an extremely rare occurrence with only six cases reported in the adult population, none in the cervical region. We report the first case of primary xanthoma of the cervical spine in a 50-year-old male solely confined to osseous compartment. The imaging mimics of lytic lesion with expansile mass in adult spine are reiterated.