Osteoid osteoma of the foot : Presentation, treatment and outcome of a multicentre cohort.

BACKGROUND: Osteoid osteomas of the foot are rare, with a varying and atypical clinical as well as radiological presentation impeding early diagnosis and treatment. The aim of the present multicentre study was to 1) analyze epidemiological, clinical and radiological findings of patients with foot osteoid osteomas and to 2) deduce a diagnostic algorithm based on the findings. METHODS: A total of 37 patients (25 males, 67.6%, mean age 23.9 years, range 8-57 years) with osteoid osteomas of the foot were retrospectively included, treated between 2000 and 2014 at 6 participating tertiary tumor centres. Radiographic images were analyzed, as were patients' minor and major complaints, pain relief and recurrence. RESULTS: Most osteoid osteomas were located in the midfoot (n = 16) and hindfoot (n = 14). Painful lesions were present in all but one patient (97.3%). Symptom duration was similar for hindfoot and midfoot/forefoot (p = 0.331). Cortical lesions required fewer x­rays for diagnosis than lesions at other sites (p = 0.026). A typical nidus could be detected in only 23/37 of x­rays (62.2%), compared to 25/29 CT scans (86.2%) and 11/22 MRIs (50%). Aspirin test was positive in 18/20 patients (90%), 31 patients (83.8%) underwent open surgery. Pain relief was achieved in 34/36 patients (outcome unknown in one), whilst pain persisted in two patients with later confirmed recurrence. CONCLUSIONS: As previously reported, CT scans seem to be superior to MRIs towards detection of the typical nidus in foot osteoid osteomas. In patients with unclear pain of the foot and inconclusive x­rays, osteoid osteoma should be considered as differential diagnosis.

Recurrence of giant cell tumour of bone: role of p53, cyclin D1, ß-catenin and Ki67.

PURPOSE: To determine various clinical, radiographic, and pathological parameters which may indicate an increased risk of Giant cell tumour of bone (GCTB) recurrence after surgical therapy. METHODS: The study included a total of 164 GCTB samples; 118 (72 %) primary tumours, and 46 (28 %) recurrences; which were analyzed on immunohistochemistry for expression of Ki67, p53, cyclin D1, and ß-catenin. RESULTS: Among 13 analyzed clinical, radiological, and histological variables, which presented possible predictive factors for the incidence of GCTB relapse, univariate logistic regression (ULR) extract three highly statistically significant parameters: 1) lesion localization, 2) nuclear p53 expression in mononuclear cells, and 3) nuclear cyclin D1 expression in giant multinuclear cells. The multivariate logistic regression (MLR), revealing that p53 expression in mononuclear cells was the most significant predictive factor (HR = 6,181 p < 0,001), the positivity of which indicated six times higher probability for recurrence in GCTB. The expression of cyclin D1 in giant cells, containing less than 15 nuclei, was also statistically significant (HR = 8,398, p = 0,038) for predicting the recurrence, and demonstrated eight times more frequent recurrence in positive tumours. CONCLUSIONS: This study confirmed independent predicting factors for GCTB reccurence: p53 expression in mononuclear tumour cells and cyclin D1 expression in giant multinuclear cells. Results are new addition to generally known parameters, such as: localization of lesion, number of surgical interventions, clear destruction of cortex with the presence of extracompartmental lesion, and histological criteria for malignancy and can help in further research and treatment of GCTB.

Significance of ß-catenin expression for the incidence of pathological fractures in giant cell tumors of bone.

Aim of the study is to determine the possible roles of p53, cyclin D1, ß-catenin and Ki-67 in the increase in risk of fractures in patients with giant cell tumor of bone. The study included a total of 164 patients with giant cell tumor of bone (GCTB), 21 (12.8%) with and 143 (87.2%) without fracture. The samples were analyzed immunohistochemically for expression of Ki-67, p53, cyclin D1 and ß-catenin. According to the immunohistochemical expression of p53 and Ki 67 in mononuclear stromal cells, as well as of cyclin D1 in multinuclear giant cells, there was no significant association with immunopositivity and risk of fractures. However, our research revealed that patients with cytoplasmic expression of b-catenin in stromal cells had three times more frequent occurrence of pathological fractures, which was highly statistically significant (χ2 = 7.065; p = 0.008). Moreover, a highly statistically significant correlation between the nuclear expression of ß-catenin in giant cells and the incidence of pathological fractures was also found (χ2 = 8.824; p = 0.003). The study showed that ß-catenin expression highly correlates with the incidence of pathological fractures in patients with GCTB. Taking into account that ß-catenin is closely linked to activation of the Wnt signaling pathway in GCTB pathogenesis, one could postulate that activation of the Wnt pathway is one of the contributing factors to locally destructive behavior of this tumor, as well as to the incidence of pathological fractures.

[Designing special prosthesis "spacer"].

Malignant diseases of the medial part of the femur, humerus and tibia, treated with surgical removal of the affected part of the bone and prosthesis fitting special "Spacer". This type of prosthesis is made in the form of the proximal and distal components that connect by screws. The design of endoprosthesis provides without possible rotation linear relationship and allows the transfer of load from the proximal to the distal bone, but the screws that provide connection are not exposed to stress. For pro-per sizing and implementation of a special prosthesis is necessary to determine the geometric parameters of bone mass and disease and then develop a computer model of the prosthesis. Designing a special prosthesis "spacer" is a complex procedure based on the processing of diagnostic images (X-ray, CT or MRI) with the use of specialized software digitized picture elements pixels translate into voxels. In this way a geometric model contains a form of external (KORTEX), and the internal geometry of the bone (medullary canal). On the basis of such a developed computer models is possible accurately determine the part of the bone that is necessary to remove, and the size of medullary canal space that is built into proximal or distal component of special endoprosthesis "Spacer".

Skeletal manifestations of hydatid disease in Serbia: demographic distribution, site involvement, radiological findings, and complications.

Although Serbia is recognized as an endemic country for echinococcosis, no information about precise incidence in humans has been available. The aim of this study was to investigate the skeletal manifestations of hydatid disease in Serbia. This retrospective study was conducted by reviewing the medical database of Institute for Pathology (Faculty of Medicine in Belgrade), a reference institution for bone pathology in Serbia. We reported a total of 41 patients with bone cystic echinococcosis (CE) during the study period. The mean age of 41 patients was 40.9±18.8 years. In 39% of patients, the fracture line was the only visible radiological sign, followed by cyst and tumefaction. The spine was the most commonly involved skeletal site (55.8%), followed by the femur (18.6%), pelvis (13.9%), humerus (7.0%), rib (2.3%), and tibia (2.3%). Pain was the symptom in 41.5% of patients, while some patients demonstrated complications such as paraplegia (22.0%), pathologic fracture (48.8%), and scoliosis (9.8%). The pathological fracture most frequently affected the spine (75.0%) followed by the femur (20.0%) and tibia (5.0%). However, 19.5% of patients didn't develop any complication or symptom. In this study, we showed that bone CE is not uncommon in Serbian population. As reported in the literature, therapy of bone CE is controversial and its results are poor. In order to improve the therapy outcome, early diagnosis, before symptoms and complications occur, can be contributive.