Bone Sarcoma Of The Pelvis: A Multicentric Retrospective Study Of One Hundred-Fourteen Cases

Background: The aim of this study was to assess the oncologic outcome of pelvic bone sarcomas (PBS) and to identify prognosis factors.Methods: We report a multicentric cohort of patients treated for a PBS from 2000 to 2020. Data from 12 hospitals were analysed. Patients treated for primary PBS were included. Alive patients with less than 6 months of follow up were excluded. The primary outcome was survival.Results: One hundred and fourteen patients (67 males and 48 females) were reviewed with a mean follow up of 32±46,5 (1 to 216) months. The mean patient and doctor diagnosis delays were respectively 8,5±10,2 (1 to 60) and 3±4,3 (0 to 24) months. Sixty-eight patients (59,6%) died after a mean time from diagnosis of 15,9±22,8 (1 to 120) months. The overall survival rates at 5 and 10 years were respectively 38,4% and 27,6%. Chondrosarcoma histological type (HR=3,64), metastasis (HR=3,55) and surgery (HR=0,12) were identified as significant survival factors. Surgery was also associated to a decreased risk of metastasis (OR=0,03, 95% CI: 0,01 – 0,1). Among the 76 patients (66,7%) who underwent surgery, local recurrence was observed in 19 patients (25%) with a mean time from surgery to onset of 11,05 (±17,5) months. Conclusions: This nation-wide20-year-cohort study shows that surgery is the most effective treatment option in PBS regardless the histological type of the tumour. Efforts have to be done to decrease the diagnosis delay in order to start treatment when surgery is still feasible.

Rotationplasty Salvage Procedure as an Effective Alternative to Femoral Amputation in an Adult With a History of Osteosarcoma: A Case Report and Review

Rotationplasty or Borggreve-Van Ness surgery is lower limb salvage surgery, indicated mainly in the management of femoral bone sarcoma and congenital femur malformations in children. It can also be an interesting surgery option for managing chronic osteoarticular infections, or in cases of non union when curative therapy is no longer an option, as an alternative to femoral amputation. The principle of this surgery is to remove the affected knee and to apply a rotation of 180° to the distal part of the lower limb in order to give the ankle the function of a neo-knee. With the help of an adapted prosthesis, the aim is to allow patients to resume their social and professional activities by keeping most of their lower limb, thus avoiding the known complications of amputation (ghost limb pain, proprioceptive deficit, psychological disorders). Nevertheless, this surgery is complex and exceptional, with vascular, infectious, and psychological risks - the chimeric aspect of the lower limb may cause significant ill-being for the patient. This article reports the case of a 38-year-old patient consulting for management of a complex septic distal femoral non-union following osteosarcoma considered as being in remission. The patient underwent rotationplasty surgery on his left lower limb, with very good functional results and no surgical revision to date. In light of this particular case, we propose a didactic overview of the literature data concerning this surgery, especially in adulthood.

Why Rotationplasty? A Qualitative Study of Decision-Making by Families of Patients With Primary Bone Sarcoma

Rotationplasty is an established technique that is indicated as part of the surgical reconstruction for certain patients with primary bone tumors around the knee who undergo tumor resection. There is considerable variation in the application of rotationplasty by surgeons as well as acceptance of the procedure by patients who may be candidates for this procedure. We qualitatively studied the decision-making process of families of patients who had undergone rotationplasty by interviewing 4 patients and their families using semi-structured interviews. Thematic analysis identified the following themes that were important in the decision-making process: (1) the desire for good information sources, (2) finding value in meeting with other patients who had been faced with a similar decision, (3) prioritizing function over cosmesis, (4) a desire to limit the need for revision surgeries, and (5) accepting that a return to normalcy is not an option with a surgery. Physicians and patients faced with a similar decision can benefit from a better understanding of the process, and by the normalization of anxieties and concerns that they may experience.

Loss of mutual protection between human osteoclasts and chondrocytes in damaged joints initiates osteoclast-mediated cartilage degradation by MMPs

Osteoclasts are multinucleated, bone-resorbing cells. However, they also digest cartilage during skeletal maintenance, development and in degradative conditions including osteoarthritis, rheumatoid arthritis and primary bone sarcoma. This study explores the mechanisms behind the osteoclast–cartilage interaction. Human osteoclasts differentiated on acellular human cartilage expressed osteoclast marker genes (e.g. CTSK, MMP9) and proteins (TRAP, VNR), visibly damaged the cartilage surface and released glycosaminoglycan in a contact-dependent manner. Direct co-culture with chondrocytes during differentiation increased large osteoclast formation (p < 0.0001) except when co-cultured on dentine, when osteoclast formation was inhibited (p = 0.0002). Osteoclasts cultured on dentine inhibited basal cartilage degradation (p = 0.012). RNA-seq identified MMP8 overexpression in osteoclasts differentiated on cartilage versus dentine (8.89-fold, p = 0.0133), while MMP9 was the most highly expressed MMP. Both MMP8 and MMP9 were produced by osteoclasts in osteosarcoma tissue. This study suggests that bone-resident osteoclasts and chondrocytes exert mutually protective effects on their ‘native’ tissue. However, when osteoclasts contact non-native cartilage they cause degradation via MMPs. Understanding the role of osteoclasts in cartilage maintenance and degradation might identify new therapeutic approaches for pathologies characterized by cartilage degeneration.

Bone cancer detection using electrical impedance tomography

Bone cancer is an uncommon sort of malignancy that alludes to irregular development of tissue inside the bone, with high opportunity to spread to different pieces of the body. It is extremely important to distinguish bone cancer at the beginning phase to cure it productively. Presently, in addition to a physical examination, magnetic resonance imaging, blood tests, positron emission tomography (PET), computed tomography (CT) or PET-CT scan, X-ray, Bone scan, Biopsy and computed tomography scan, are used to diagnose or determine the stage (or extent) of bone sarcoma. But these methods are costly and not free of radiation. Moreover, these machines are bulky. Electrical impedance tomography approach was proposed in this research for identifying bone cancer as this detection technique is able to distinguish between cancerous and non-cancerous cells by differentiating between their conductivity and it has the possibility to remove the limitations of conventional medical imaging techniques. Here, equivalent bone models were generated using (electrical impedance and diffused optical reconstruction software (EIDORS) which had been implemented in MATLAB, and three different image reconstruction algorithms-GREIT, Sheffield Backprojection, Gauss-Newton inverse algorithm had been used to detect the cancerous cells.