Dedifferentiated chordoma is a rare and aggressive variant of the conventional tumour in which an area undergoes transformation to a high-grade lesion, typically fibrous histiocytoma, fibrosarcoma, and rarely, osteosarcoma or rhabdomyosarcoma. The dedifferentiated component dictates overall survival, with smaller areas of dedifferentiation carrying a more favourable prognosis. Although it is more commonly diagnosed in recurrences and following radiotherapy, there have been a few reports of spontaneous development. We describe four such cases, which were diagnosed de novo following primary excision, and discuss the associated clinical and radiological features

We evaluated the long-term functional outcome in 118 patients treated for osteosarcoma or Ewing’s sarcoma in the extremities a minimum of five years after treatment. We also examined if impaired function influenced their quality of life and ability to work. The function was evaluated according to the Musculoskeletal Tumor Society (MSTS) score and the Toronto Extremity Salvage Score (TESS). Quality of life was assessed by using the Short Form-36 (SF-36). The mean age at follow-up was 31 years (15 to 57) and the mean follow-up was for 13 years (6 to 22). A total of 67 patients (57%) initially had limb-sparing surgery, but four had a secondary amputation. The median MSTS score was 70% (17% to 100%) and the median TESS was 89% (43% to 100%). The amputees had a significantly lower MSTS score than those with limb-sparing surgery (p < 0.001), but there was no difference for the TESS. Tumour localisation above knee level resulted in significantly lower MSTS scores and TESS (p = 0.003 and p = 0.02, respectively). There were no significant differences in quality of life between amputees and those with limb-sparing surgery except in physical functioning. Of the patients 11% (13) did not work or study. In multivariate analysis, amputation, tumour location above the knee and having muscular pain were associated with low physical function. We conclude that most of the bone tumour survivors managed well after adjustment to their physical limitations. A total of 105 are able to work and have an overall good quality of life

Aims

The modified Glasgow Prognostic Score (mGPS) uses preoperative CRP and albumin to calculate a score from 0 to 2 (2 being associated with poor outcomes). mGPS is validated in multiple carcinomas. To date, its use in soft-tissue sarcoma (STS) is limited, with only small cohorts reporting that increased mGPS scores correlates with decreased survival in STS patients.

Aims

Osteoarthritis (OA) is prevalent among the elderly and incurable. Intra-articular parathyroid hormone (PTH) ameliorated OA in papain-induced and anterior cruciate ligament transection-induced OA models; therefore, we hypothesized that PTH improved OA in a preclinical age-related OA model.

The total plasma alkaline phosphatase level has long been recognised as an indicator of osteoblastic activity, but lack of specificity makes it an insensitive index of the progress of disease and the response to treatment. Selective precipitation by wheatgerm lectin allows measurement of the plasma bone-specific alkaline phosphatase. We measured the plasma levels of this isoenzyme in 170 normal Chinese adolescents and adults, in 49 adults with fractures of a long bone, in 15 patients with osteosarcoma and in 38 patients with osteolytic metastases. The enzyme activity was also determined in 39 patients with liver disease. Of the patients with fractures, 94% had increased plasma activity during the healing process. The level was also increased in those with osteosarcoma but not in those with osteolytic bone metastases. There was no significant increase in activity in the patients with liver disease. We conclude that the plasma bone-specific alkaline phosphatase activity is a sensitive and reliable measure of osteoblastic activity

We have carried out prosthetic reconstruction in six patients with malignant or aggressively benign bone tumours of the distal tibia or fibula. The diagnoses were osteosarcoma in four patients, parosteal osteosarcoma in one and recurrent giant-cell tumour in one. Five tumours were in the distal tibia and one in the distal fibula. The mean duration of follow-up was 5.3 years (2.0 to 7.1). Reconstruction was achieved using custom-made, hinged prostheses which replaced the distal tibia and the ankle. The mean range of ankle movement after operation was 31° and the joints were stable. The average functional score according to the system of the International Society of Limb Salvage was 24.2 and five of the patients had a good outcome. Complications occurred in two with wound infection and talar collapse. All patients were free from neoplastic disease at the latest follow-up. Prosthetic reconstruction may be used for the treatment of malignant tumours of the distal tibia and fibula in selected patients

We investigated the possible use of acrylic cement containing chemotherapeutic drugs in the treatment of malignant lesions in bone. The diffusion of methotrexate (MTX) from methylpolymethacrylate implants was studied in vitro: polymerisation of the cement did not destroy the drug; liberation began immediately and about 10% was released by 18 hours. Some release continued for as long as six months. In vivo experiments on rats with induced osteosarcoma showed that MTX in cement had both local and general effects which were dependent on the dosage. A series of 17 large dogs with spontaneous osteosarcoma were then treated by local resection and cement containing MTX. General chemotherapeutic effects were detectable from 2 hours to 5 days, survival was increased and local recurrence was reduced, but there were four cases of delayed wound healing. Preliminary studies in human patients confirm the possibility that this method of local chemotherapy could be a useful addition to the treatment of malignant tumours of bone

The clinical records, radiographs and histopathological material of all forty-one patients recorded as suffering from fibrosarcoma of bone in the Swedish Cancer Registry for the years 1958 to 1968 have been analysed; in addition, four cases were found on histological review of a series of osteosarcomas. From this re-examination, twenty-four patients with genuine fibrosarcoma of bone were identified; twenty-two had primary neoplasms and two secondary. No sex or geographical differences were found. The tumours showed a prevalence for patients in the adult and older age groups. Half of the tumours arose from femoral or tibial metaphysial bone adjacent to a knee joint. All the tumours were of the medullary type. Almost one-third presented with a pathological fracture, and soft-tissue extension had occurred in all but three tumours. In contrast to previous reports, these tumours were more malignant than osteosarcomas and showed a five-year survival rate of only 4-2 per cent. In accessible sites, ablative surgery was used as the primary treatment, Fibrosarcoma of bone is a distinctive lesion and should be distinguished carefully from periosteal and soft-tissue fibrosarcomas because of differences in prognosis and treatment

1. That viruses may be involved in the causation of human tumours has long been suspected but not yet proved. The discovery that osteogenic sarcoma can be induced by viral agents in mice and hamsters makes the proposition that human sarcomas may also have a viral origin basically tenable on presently available evidence. In order to distinguish between passengers and causative agents it will probably be necessary to demonstrate antigenic cross-reactivity in tumours of similar type collected from different geographical areas, and the oncogenicity in subhuman primates of extracts containing virus from human tumours. Such information is likely to become available in the next few years. 2. The demonstration of tumour-specific immune reactions in an increasing number of patients with various forms of neoplasm, including skeletal sarcomas, and the correlation of these reactions with the clinical status of the disease sustains the hope that eventually immunotherapy may contribute to the control of cancer in man. 3. Animal experiments have revealed that the potentiation of immune responses may lead to the elimination of small foci of neoplastic cells. The role of immunotherapy in the treatment of cancer may therefore be as an adjunct to surgery, radiotherapy and chemotherapy (Alexander 1968). Once the primary tumour has been removed it may be possible to employ immunotherapeutic measures to destroy the relatively few remaining cells that give rise to late metastases; this is particularly apposite to juvenile osteosarcoma

Disarticulation of the hip in patients with high-grade tumours in the upper thigh results in significant morbidity. In patients with no disease of the proximal soft tissue a femoral stump may be preserved, leaving a fulcrum for movement and weight-bearing. We reviewed nine patients in whom the oncological decision would normally be to disarticulate, but who were treated by implantation of an endoprosthesis in order to create a functioning femoral stump. The surgery was undertaken for chondrosarcoma in four patients, pleomorphic sarcoma in three, osteosarcoma in one and fibrous dysplasia in one. At follow-up at a mean of 80 months (34 to 132), seven patients were alive and free from disease, one had died from lung metastases and another from a myocardial infarction. The mean functional outcome assessment was 50 (musculoskeletal tumor society), 50 and 60 (physical and mental Short-form 36 scores). Implantation of an endoprosthesis into the stump in carefully selected patients allows fitting of an above-knee prosthesis and improves wellbeing and the functional outcome

Out of 21 900 cases filed at the Latin-American Registry of Bone Pathology between April 1940 and July 1981, there were 987 with Paget's disease (4.51 per cent); 62 of these (6.28 per cent) were complicated by sarcoma and two were associated with giant-cell tumours of bone (osteoclastoma) without signs of malignancy. There was a slight predominance of men and the ages ranged from 45 to 87 years, with an average of 66 years. The most frequent sites were the femur (23 cases), the humerus (nine), the pelvis (10), and the tibia (nine). The low incidence of vertebral involvement (five cases) is noteworthy and is in sharp contrast to uncomplicated Paget's disease. The most common tumour type was osteosarcoma (39 cases), followed by fibrosarcoma (15 cases); other varieties (chondrosarcoma, malignant fibrous histiocytoma and reticulum-cell sarcoma) were much rarer. Most of the sarcomata occurred when the Paget's disease was polyostotic. Tumours often developed simultaneously, or at short time intervals, in the same or different bones; these bones had, in all cases, been affected by Paget's disease. The histological features of the osteosarcomata were characteristic, with large numbers of osteoclast giant cells, alternating with atypical osteoblasts, thus exaggerating the anarchic remodelling process of Paget's disease. The neighbouring areas of the pagetic bone showed an increased number of osteoclasts. These facts suggest a possible pathogenetic relationship between sarcoma and Paget's disease; the possibility of both processes having a viral aetiology is discussed

1. Histochemical staining and correlated biochemical estimations of five hydrolytic enzymes were done on eighteen benign and twenty malignant fibroblastic lesions of bone and soft tissue. 2. Alkaline phosphatase activity was moderate in a fibroma and very high in fibrous dysplasia. In a typical fibrosarcoma the fibroblasts showed no enzyme activity and estimations were low. Exceptions indicated an osteogenic potential in the tumour. 3. ß-glucuronidase, leucine aminopeptidase, and to a less extent non-specific esterase, were more active in malignant than in benign lesions, and the highest activities were found in sarcomata arising in Paget's disease of bone. 4. Acid phosphatase showed no correlation with malignancy and was generally unremarkable except for high activity in osteoclasts, but was raised in two sarcomata that occurred after irradiation of giant-cell tumours. 5. A non-osteogenic fibroma and a fibrous cortical defect, though poorly represented in this series, are not uncommon; they sometimes lead to pathological fracture, but sarcoma is very rare in such lesions. They tend to show more alkaline phosphatase than fibrosarcoma but not the very high activity of fibrous dysplasia, which is related to its osteogenic potential. 6. Fibrous dysplasia most often presents in the five to fifteen age group but seldom leads to malignancy, though this may occur, usually as osteosarcoma, which has a similar high content of alkaline phosphatase. Fibrosarcoma is typically negative or very weak in this enzyme: the exceptional cases with high activity were tumours which were in part osteosarcoma. Generally the demonstration of high alkaline phosphatase activity in a fibroblastic lesion of bone, in the absence of trauma or inflammation, suggests the diagnosis of fibrous dysplasia

Aims

Cell-free DNA (cfDNA) and circulating tumour DNA (ctDNA) are used for prognostication and monitoring in patients with carcinomas, but their utility is unclear in sarcomas. The objectives of this pilot study were to explore the prognostic significance of cfDNA and investigate whether tumour-specific alterations can be detected in the circulation of sarcoma patients.

We have attempted to summarise in a short space investigations that have occupied several years, and we realise that whatever the merits of such an effort the results can only be modest. Many important aspects of the osteogenetic process still remain a mystery and thus are subjected to theory and controversy. Such is the case with this constant attendant at osteogenesis which is alkaline phosphatase. But of one thing we are certain, namely that bone is an organised "soft" tissue of which only part has been made rigid by the deposit of calcium salts. The organiser is the osteogenetic vessel from which springs the syncytial frame of cells and their connections on which the bone architecture is established. Endothelial cell, intermediate cell, osteoblast, osteocyte, osteoclast; these constitute the normal sequence of cellular phylogeny in the constant elaboration and removal of the bone substance. The initial cells on which the whole process rests are those of the capillary-sinusoid vessel which is responsible for providing the transudates on which the life and health of the whole syncytium depends. If our findings were confirmed, a better understanding of the nature and characteristics of primitive malignant bone tumours would be possible. Each type of tumour from endothelioma to malignant osteoclastoma, including reticulum-cell sarcoma and osteogenic sarcoma, would be initiated by a different cell of the syncytium, but in its monstrous deviation from the normal would still preserve most of the characteristics of its healthy ancestor. Thus the endothelioma causes bone expansion, bone reaction and even bone necrosis, but not proper bone formation, whereas the osteogenic sarcoma or osteoblastoma forms bone; and with the same fidelity to their origin osteoclasts are seen in the malignant osteolytic tumour. Over thirty years ago the late Sir Arthur Keith (1927) expressed his suspicion that the cells which assume a bone-forming role are derived from the endothelium of the capillary system. We hope we have contributed to show that his suspicion was right

Aims

Orthopaedic and reconstructive surgeons are faced with large defects after the resection of malignant tumours of the sacrum. Spinopelvic reconstruction is advocated for resections above the level of the S1 neural foramina or involving the sacroiliac joint. Fixation may be augmented with either free vascularized fibular flaps (FVFs) or allograft fibular struts (AFSs) in a cathedral style. However, there are no studies comparing these reconstructive techniques.

Aims

Rotating-hinge knee prostheses are commonly used to reconstruct the distal femur after resection of a tumour, despite the projected long-term burden of reoperation due to complications. Few studies have examined the factors that influence their failure and none, to our knowledge, have used competing risk models to do so. The purpose of this study was to determine the risk factors for failure of a rotating-hinge knee distal femoral arthroplasty using the Fine-Gray competing risk model.