Clinical impact of whole-body MRI in staging and surveillance of patients with myxoid liposarcoma: a 14-year single-centre retrospective study

OBJECTIVE

To assess the clinical impact of regular whole-body magnetic resonance imaging (WBMRI) surveillance in myxoid liposarcoma patients.

METHODS

This was a retrospective cohort study of myxoid liposarcoma patients who underwent at least one WBMRI at our institution between October 2006 and December 2020. The effect of WBMRI on clinical management, namely treatment modification or additional diagnostic investigations was studied. A standardised WBMRI surveillance protocol was instituted in 2015. We compared patient outcomes for the metastatic patients who had and had not received regular WBMRI surveillance and performed survival analysis for both subgroups.

RESULTS

Of the 56 patients (60.7% male, median age: 48.1 years) who underwent 345 WBMRI, 17 (30.3%) had metastases, and 168 WBMRI were performed in this group. The median imaging follow-up for the entire cohort was 35 months; the metastatic group had a median follow-up of 42 months. WBMRI changed the clinical management in 13 (76.5%) metastatic patients, with 33 instances of treatment modification. Thirty-five lesions were labelled 'indeterminate,' 16 (45.7%) had additional investigations/interventions, and 4 (11.4%) were confirmed to be metastatic. Twenty-one metastatic lesions were missed initially on WBMRI and confirmed on subsequent WBMRI, of which 5 (23.8%) were clinically significant. The 5-year survival since the detection of metastasis was better in the regular surveillance subgroup (85.7% vs. 45%), but this was not statistically significant (p = 0.068). Five patients (8.9%) developed their first metastasis more than 5 years after diagnosing the primary lesion.

CONCLUSION

Regular WBMRI surveillance of myxoid liposarcoma patients considerably impacts clinical management by frequently influencing treatment decisions.

CLINICAL RELEVANCE STATEMENT

WBMRI has been recently recommended as an imaging option for the staging and surveillance of myxoid liposarcoma patients. Our study highlights the impact of regular WBMRI surveillance on the clinical management of these patients and how it affects their survival.

Patient-physician agreement on function and pain is associated with long-term outcomes in sarcoma: findings from a longitudinal study

PURPOSE

We aimed to describe the level of agreement between patients and physicians on the ratings of daily functioning and pain in a cohort of sarcoma patients and assess how (dis)agreement and its change over time predicted patient-reported outcomes in survivorship.

METHOD

We performed secondary analysis of longitudinal data from a sarcoma-specialty clinic in Montreal, Canada. Demographics, clinical characteristics and patient-physician agreement were summarized descriptively. Linear mixed models were used to assess the effects of time, baseline agreement, change in agreement over time, interaction of time and change in agreement and 12-month daily functioning, quality of life, and fatigue.

RESULTS

Data were available for 806 patients (57.7% male, x̄ = 53.3 years) who completed at least one questionnaire. Patient-physician disagreement was common on the level of function (43.4%) and pain (45.7%). Baseline physician-patient agreement was associated with better 12-month outcomes. Improvement in agreement on function over time was significantly associated with daily functioning (F(2, 212) = 3.18, p = 0.043) and quality of life (F(2, 212) = 3.17, p < 0.044). The pattern was similar though less pronounced for the agreement on pain.

CONCLUSIONS

Our study offers novel insights into the importance of patient-physician agreement and communication's role in long-term patient-reported outcomes in sarcoma.

IMPLICATIONS FOR CANCER SURVIVORS

The results emphasize the importance of mutual understanding of symptoms and patients' needs and suggest that further consultation in cases of discordance of ratings and opinions might be beneficial for optimal survivorship.

Occupational injuries and burn out among orthopedic oncology surgeons

BACKGROUND

Orthopedic oncology surgeons commonly engage in prolonged and complex surgical procedures. These types of surgeries increase the risk of physical and psychological stressors, which may in turn make these physicians prone to work-related occupational injuries.

AIM

The aim of this study was to explore in orthopedic oncologists, the prevalence of work-related physical injuries and psychological disturbances.

METHODS

A modified version of the physical discomfort survey was developed to assess occupational injuries among orthopedic oncology surgeon members of the Musculoskeletal Tumor Society, the Canadian Orthopedic Oncology Society and European Musculoskeletal Oncology Societies. The survey was sent by email, and it explored musculoskeletal complaints, psychological disturbances, treatment required for these complaints and the requirement of time off work.

RESULTS

A total of 67 surgeon responses were collected. A high number of orthopedic oncologists (84%) reported an occupational injury. Low back pain (39%) was the most prevalent musculoskeletal condition, followed by lumbar disk herniation (16%), shoulder tendinitis (15%) and lateral epicondylitis (13%). Of the cohort, 46% required surgery and 31% required time off work due to their injury. Thirty-three respondents reported a psychological disorder. Burnout (27%), anxiety (20%) and insomnia (20%) were the most commonly reported. Time required off work due to injury was associated with old age and years in practice.

CONCLUSION

Orthopedic oncology surgeons report a high prevalence of work-related disorders. Lower back related injury and burnout were the most reported disorders. Improving operative room ergonomics and prevention of stress related to the work environment should be areas to explore in upcoming research.

Joint-sparing Reconstruction for Extensive Periacetabular Metastases: Literature Review and a Novel Minimally Invasive Surgical Technique

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Metastasis accounts for nearly half of pathologic acetabular reconstructions.

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Increasing use of combined percutaneous ablation, cementoplasty, and osteosynthesis.

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Harrington or MAC classification may lead to overtreatment of acetabular lesions.

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Know indications for joint-sparing reconstruction; consider use in select patients.

Classically, patients with advanced lytic disease of the acetabulum secondary to metastatic bone disease are treated with complex arthroplasty reconstruction techniques. Advancements in percutaneous techniques have extended the indications for safer, minimally invasive procedures for patients with periacetabular metastasis without the need for complex hip replacement and the complications that follow it. The purpose of this report is to revisit the management of this group of patients and provide indications for an alternative minimally invasive joint-sparing technique. We describe a novel technique using a combination of percutaneous cryoablation, cementoplasty and two-screw fixation. With careful consideration of indications, excellent functional and oncologic outcomes one year after surgery is possible without the need for additional procedures.

Megaprosthesis anti-bacterial coatings: A comprehensive translational review

Periprosthetic joint infections (PJI) are catastrophic complications for patients with implanted megaprostheses and pose significant challenges in the management of orthopaedic oncology patients. Despite various preventative strategies, with the increasing rate of implanted orthopaedic prostheses, the number of PJIs may be increasing. PJIs are associated with a high rate of amputation. Therefore, novel strategies to combat bacterial colonization and biofilm formation are required. A promising strategy is the utilization of anti-bacterial coatings on megaprosthetic implants. In this translational review, a brief overview of the mechanism of bacterial colonization of implants and biofilm formation will be provided, followed by a discussion and classification of major anti-bacterial coatings currently in use and development. In addition, current in vitro outcomes, clinical significance, economic importance, evolutionary perspectives, and future directions of anti-bacterial coatings will also be discussed. Megaprosthetic anti-bacterial coating strategies will help reduce infection rates following the implantation of megaprostheses and would positively impact sarcoma care. STATEMENT OF SIGNIFICANCE: This review highlights the clinical challenges and a multitude of potential solutions to combating peri-prosthetic join infections in megaprotheses using anti-bacterial coatings. Reducing infection rates following the implantation of megaprostheses would have a major impact on sarcoma care and major trauma surgeries that require reconstruction of large skeletal defects.

Aggressive Behavior Predictors in Solitary Fibrous Tumor: Demographic, Clinical, and Histopathologic Characteristics of 81 Cases

BACKGROUND

Solitary fibrous tumor (SFT) is a rare mesenchymal tumor with an intermediate tendency to metastasize. Meningeal hemangiopericytoma (HPC), arising in the meningeal membranes, also is considered an SFT. Although SFT is assumed to show an unpredictable behavior, the authors defined some factors associated with its aggressive behavior.

METHODS

This retrospective study was based on the medical records of 81 SFT patients treated surgically, with the median follow-up period of 59 months. The patients were assigned to three histopathologic groups based on the 2016 WHO classification: group 1 (SFT, 29 patients), group 2 (cellular SFT/hemangiopericytoma [HPC], 27 patients), and group 3 (malignant SFT/anaplastic HPC, 25 patients).

RESULTS

The SFT histopathologic classification was associated with distant metastasis (DM) (p = 0.007). The multivariate analysis showed that cellular SFT had an independent impact on DM (odds ratio [OR] = 25.42; p = 0.006). Tumor diameter larger than 7.25 cm was correlated with DM (p = 0.010) and the patient's disease-specific death (DSD) (p = 0.007). A 1-cm increase in tumor diameter enhanced the likelihood of metastasis by 1.26 (OR = 1.26; 95% confidence interval [CI], 1.05-1.53). Tumors originating from the central nervous system (CNS) showed a greater tendency toward local recurrence (LR) (p = 0.039) and DM (p = 0.05). Radiotherapy had no association with LR, DM, or DSD. The 10-year disease-specific survival rate was 82.7%.

CONCLUSIONS

Tumor size and histopathologic diagnosis are the predictors of SFT's aggressive behavior. Cellular SFTs behave as aggressively as the malignant form of the tumor. A SFT grading based on SFT cellularity would contribute to anticipation of its aggressive behavior.

Radiographic, Functional, and Oncologic Outcomes of Cemented Modular Proximal Femur Replacement Using the "French Paradox" Technique

BACKGROUND

Endoprostheses are frequently used in the management of tumors involving the proximal femur. Aseptic loosening is a common complication that has been linked to the cementing technique. The "French paradox" is well-known cementing technique in the arthroplasty literature. No previous reports have assessed loosening in proximal femur replacements using this technique. We examined rates of femoral stem aseptic loosening in proximal femur replacements, functional outcomes, complications, and oncologic outcomes.

METHODS

We conducted a retrospective review of 47 patients who underwent proximal femur replacement between 2000 and 2019. Two reviewers evaluated preoperative and postoperative radiographs using the International Society of Limb Salvage scoring system and Barrack criteria for stem loosening. The acetabulum was evaluated according to the criteria of Baker et al. Functional outcomes were assessed using Musculoskeletal Tumor Society (MSTS) score and Toronto Extremity Salvage Score. The mean follow-up was 44 months.

RESULTS

The mean International Society of Limb Salvage scores for the 2 reviewers were 86% ± 6% and 84% ± 6%. The first reviewer graded femoral stem loosening as "possibly loose" in 2 patients, one of whom was graded as possibly loose by the second reviewer. The 2 reviewers found no acetabular erosion in 16 (70%) and 15 (65.4%) patients, respectively. The mean Musculoskeletal Tumor Society score and Toronto Extremity Salvage Score at last follow-up were 61% and 72%, respectively. Twenty complications occurred in 13 patients, and 5 patients experienced local recurrence.

CONCLUSION

Despite complications, we showed favorable femoral component survival rates. Cementing the proximal femur prosthesis with tight canal fit and thin cement mantle is a viable option for the short and medium term.

LEVEL OF EVIDENCE

III.

Psychological functioning, coping styles and their relationship to appraisal of physical limitations following invasive surgical procedures for soft-tissue sarcoma: A qualitative study

BACKGROUND AND OBJECTIVES

This study explored psychological functioning and coping styles in adult patients with soft-tissue sarcoma who underwent surgical procedures in a single expert sarcoma medical center in Canada.

METHODS

This is a qualitative study with three formats of data collection. The interview guide was based on theoretical health-related quality of life model. We began the investigation with 2 online and 2 in-person focus groups. Four individual semistructured interviews were added to further explore emerging themes. Data were analyzed using inductive thematic networks approach.

RESULTS

Twenty-eight adults (13 female, 24-75 years of age) participated. In the domain of psychological functioning we identified three main themes; changes in mood, worry, and body image concerns. In the domain of coping styles, we identified four adaptive coping styles; positive reframing and optimism, finding a purpose, being proactive, and using humor. Among the maladaptive coping styles, we found passive acceptance, and avoidance and denial.

CONCLUSIONS

Psychological well-being can be contingent on physical functioning and coping styles in adults with soft-tissue sarcoma. Both psychological and physical function impact quality of life. Patients with more physical limitations, psychological distress and maladaptive coping styles should be monitored for their well-being.

The Pediatric Toronto Extremity Salvage Score (pTESS): Validation of a Self-reported Functional Outcomes Tool for Children with Extremity Tumors

BACKGROUND

The physical function of children with sarcoma after surgery has not been studied explicitly. This paucity of research is partly because of the lack of a sufficiently sensitive pediatric functional measure. The goal of this study was to establish and validate a standardized measure of physical function in pediatric patients with extremity tumors.

QUESTIONS/PURPOSES

(1) What is the best format and content for new upper- and lower-extremity measures of physical function in the pediatric population? (2) Do the new measures exhibit floor and/or ceiling effects, internal consistency, and test-retest reliability? (3) Are the new measures valid?

METHODS

In Phase 1, interviews with 17 consecutive children and adolescents with bone tumors were conducted to modify the format and content of draft versions of the pediatric Toronto Extremity Salvage Score (pTESS). In Phase 2, the pTESS was formally translated into French. In Phase 3, 122 participants between 7 and 17.9 years old with malignant or benign-aggressive bone tumors completed the limb-specific measure on two occasions. Older adolescents also completed the adult TESS. Floor and ceiling effects, internal consistency, test-retest reliability, and validity were evaluated.

RESULTS

Feedback from interviews resulted in the removal, addition, and modification of draft items, and the pTESS-Leg and pTESS-Arm questionnaires were finalized. Both versions exhibited no floor or ceiling effects and high internal consistency (α > 0.92). The test-retest reliability was excellent for the pTESS-Leg (intraclass correlation coefficient [ICC] = 0.94; 95% CI, 0.90-0.97) and good for the pTESS-Arm (ICC = 0.86; 95% CI, 0.61-0.96). Known-group validity (ability to discriminate between groups) was demonstrated by lower mean pTESS-Leg scores for participants using gait aids or braces (mean = 68; SD = 21) than for those who did not (mean = 87; SD = 11; p < 0.001). There was no significant difference between pTESS arm scores among respondents using a brace (n = 5; mean = 73; SD = 11) and those without (n = 22; mean = 83; SD = 19; p = 0.13). To evaluate construct validity, we tested a priori hypotheses. The duration since chemotherapy correlated moderately with higher pTESS-Leg scores (r = 0.4; p < 0.001) but not with pTESS-Arm scores (r = 0.1; p = 0.80), and the duration since tumor resection correlated moderately with higher pTESS-Leg scores (r = 0.4; p < 0.001) but not pTESS-Arm scores (r = 0.2; p = 0.4). Higher VAS scores (that is, it was harder to do things) antecorrelated with both pTESS versions (pTESS-Leg: r = -0.7; p < 0.001; pTESS-Arm: r = -0.8; p < 0.001). To assess criterion validity, we compared the pTESS with the current "gold standard" (adult TESS). Among adolescents, strong correlations were observed between the TESS and pTESS-Leg (r = 0.97, p < 0.001) and pTESS-Arm (r = 0.9, p = 0.007).

CONCLUSIONS

Both pTESS versions exhibited no floor or ceiling effects and had high internal consistency. The pTESS-Leg demonstrated excellent reliability and validity, and the pTESS-Arm demonstrated good reliability and reasonable validity. The pTESS is recommended for cross-sectional evaluation of self-reported physical function in pediatric patients with bone tumors.

LEVEL OF EVIDENCE

Level II, outcome measurement development.

Arthroscopic Management of Osteoid Osteoma of the Ankle Joint: A Systematic Review of the Literature

Osteoid osteomas (OOs) are rare benign bone tumors that may occur in various joints including the ankle. These tumors are generally removed via open surgical excision or radiofrequency ablation. However, when they occur intra-articularly, these treatments are more difficult to perform because of more difficult access and the increased risk of damaging articular cartilage. Therefore, some have advocated for the use of arthroscopy to treat these cases. This systematic review aims to investigate the safety and efficacy of arthroscopic treatment for intra-articular OO of the ankle. Using Medline and Embase, we systematically reviewed the literature as of May 31, 2017. All articles published on and before that date were reviewed by 2 independent reviewers. Seventeen articles containing a total of 27 cases were included in the review. Most reported cases were in the talar neck, followed by the distal tibia. Of all the cases, only 2 recurrences were reported (in the same patient), and no complications were reported. Therefore, these cases demonstrate arthroscopic excision of intra-articular OO of the ankle as a safe and effective alternative to open surgical excision and radiofrequency ablation, with a success rate of 96%. However, all articles found were case studies or small case series owing to the rarity of this disease. In the future, analyses of case series with larger case collections should be performed.

Early detection of metastases using whole-body MRI for initial staging and routine follow-up of myxoid liposarcoma

OBJECTIVE

To define the role of whole-body MRI (WBMRI) for initial staging and routine follow-up of myxoid liposarcoma (MLS).

MATERIALS AND METHODS

A retrospective review of all the patients with MLS who underwent WBMRI for initial staging and routine follow-up at our institution between October 1, 2006, and September 30, 2016 was performed. Patient demographics, clinical presentation, imaging findings, tumor histology, and occurrence and location of metastatic disease were recorded. Thirty-three patients who underwent a total of 150 WBMRI examinations were included in the study.

RESULTS

Nine patients (27%) were diagnosed with metastases between 0 and 60 months (median 10; interquartile range, 7-13) from the diagnosis of the primary tumor. The initial site of metastatic disease was extrapulmonary in all patients. Only two patients developed pulmonary metastases, which were diagnosed by CT chest 9 and 29 months after the diagnosis of extrapulmonary metastases. The first metastasis was diagnosed by WBMRI in seven patients (78%), by thoracic CT in one patient, and by abdominal CT in one patient. Eight of nine patients (89%) were asymptomatic at the time of diagnosis of the metastases. In seven patients (78%), WBMRI demonstrated metastases included within the field of view of, but occult on a contemporaneous CT scan.

CONCLUSION

Our 10-year institutional experience demonstrates that WBMRI facilitates early detection of extrapulmonary MLS metastases before the onset of clinical symptoms and pulmonary metastases. WBMRI also depicts extrapulmonary metastases that are occult on CT scans. The current surveillance strategies are insufficient for screening for extrapulmonary MLS metastases.

Histone H3K36 mutations promote sarcomagenesis through altered histone methylation landscape

Several types of pediatric cancers reportedly contain high-frequency missense mutations in histone H3, yet the underlying oncogenic mechanism remains poorly characterized. Here we report that the H3 lysine 36-to-methionine (H3K36M) mutation impairs the differentiation of mesenchymal progenitor cells and generates undifferentiated sarcoma in vivo. H3K36M mutant nucleosomes inhibit the enzymatic activities of several H3K36 methyltransferases. Depleting H3K36 methyltransferases, or expressing an H3K36I mutant that similarly inhibits H3K36 methylation, is sufficient to phenocopy the H3K36M mutation. After the loss of H3K36 methylation, a genome-wide gain in H3K27 methylation leads to a redistribution of polycomb repressive complex 1 and de-repression of its target genes known to block mesenchymal differentiation. Our findings are mirrored in human undifferentiated sarcomas in which novel K36M/I mutations in H3.1 are identified.

Use of Ligament Advanced Reinforcement System tube in stabilization of proximal humeral endoprostheses

AIM: To review outcomes following usage of the Ligament Advanced Reinforcement System (LARS^®) in shoulder tumors.

METHODS: Medical records of nineteen patients (19 shoulders) that underwent tumor excisional procedure and reconstruction with the LARS synthetic fabric, were retrospectively reviewed.

RESULTS: Patients’ median age was 58 years old, while the median length of resection was 110 mm (range 60-210 mm). Compared to immediate post-operative radiographs, the prosthesis mean end-point position migrated superiorly at a mean follow up period of 26 mo (P = 0.002). No statistical significant correlations between the prosthesis head size (P = 0.87); the implant stem body length (P = 0.949); and the length of resection (P = 0.125) with the position of the head, were found at last follow up. Two cases of radiological dislocation were noted but only one was clinically symptomatic. A minor superficial wound dehiscence, healed without surgery, occurred. There was no evidence of aseptic loosening either, and no prosthetic failure.

CONCLUSION: LARS^® use ensured stability of the shoulder following endoprosthetic reconstruction in most patients.

Hip arthroscopy for the management of osteoid osteoma of the acetabulum: a systematic review of the literature and case report

Background

Intra-articular osteoid osteoma (OO) causes irreversible joint damage. Its treatment of choice is radiofrequency ablation (RFA); however, some areas of the acetabulum are hard to access. Therefore, hip arthroscopy was used to treat this tumor. We aim to systematically review the literature with regards to arthroscopic management of acetabular OO, and to report a further case in which hip arthroscopy was used for treatment.

Methods

PubMed and EMBASE were searched for articles relevant to the arthroscopic management of acetabular OO on December 2, 2014. All articles published on and before that date were reviewed, and studies which met our pre-determined inclusion criteria were included. Articles screening and data abstraction were done by two reviewers independently. We also presented a 31-year-old man with acetabular OO who underwent hip arthroscopy for the management of his tumor after failing to respond to medications and computed tomography scan (CT)-guided RFA.

Results

The initial search revealed 14 studies, of which ten met our inclusion criteria. A total of ten patients underwent hip arthroscopy for the management of acetabular OO. Only two patients were females, and the patients' age ranged from 7 to 47 years. Two patients underwent arthroscopic guided-RFA of the lesion, while the rest underwent excision. The follow-up period ranged from 6 months to 2 years. Success rate was 100 %, and no recurrence was reported. Minor complications (transient impotence and perineal numbness) developed in one patient (10 %). Arthroscopic-guided RFA failed to eliminate the tumor in our additional case. A second trial of CT-guided RFA was successful in treating the patient's condition.

Conclusions

Hip arthroscopy is an effective and safe option for the management of acetabular OO, with success rate exceeding 90 %. Studies of higher level of evidence are required.

Electronic supplementary material

The online version of this article (doi:10.1186/s12891-015-0779-8) contains supplementary material, which is available to authorized users.

Skin elasticity as a measure of radiation fibrosis: is it reproducible and does it correlate with patient and physician-reported measures?

Current means of measuring RT-induced fibrosis are subjective. We evaluated the DermaLab suction cup system to measure objectively skin deflection as a surrogate for fibrosis. Sixty-nine patients with E-STS were treated with limb-sparing surgery and 50-66 Grays (Gy) of RT. Using a “scleroderma” DermaLab Suction Cup, the skin stiffness was measured by two clinicians. The National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE) scale, the Musculoskeletal Tumor Rating Scale (MSTS) and Toronto Extremity Salvage Score (TESS) questionnaires were completed for each patient. Levels of agreement between measurers were estimated using the Kappa (κ) coefficient and the concordance correlation coefficient (CCC). All sixty-nine patients were included. The level of agreement between measurers for NCI-CTCAE grading was moderate (range κ = 0.41-0.59). The CCC for the elasticity measurements were higher, with CCC = 0.82 for fibrotic skin and CCC = 0.84 for normal skin. The elasticity measurements were significantly higher when MSTS scores were <30 and or TESS scores were <90. Suction Cup measurement of skin elasticity is more reproducible than CTCAE grading and shows promise in generating reproducible measurements for radiation-induced skin fibrosis. Furthermore, it correlates well with the MSTS and TESS.

Iterative curettage is associated with local control in giant cell tumors involving the distal tibia

BACKGROUND

The distal tibia is an unusual location for a giant cell tumor (GCT). Treatment choices are unclear because of their rarity, the anatomy of the ankle, and difficulties associated with reconstruction.

QUESTIONS/PURPOSES

We assessed: (1) the treatment modalities used by participating Canadian bone tumor centers for distal tibia GCTs; (2) the incidence of local recurrence and their management; and (3) patients' function after treatment.

METHODS

A prospective tumor database served to identify all 31 patients with primarily treated distal tibia GCTs between 1991 and 2010. We extracted patients and tumor characteristics, treatment modalities for initial and recurrent tumors, and the Musculoskeletal Tumor Society (MSTS) and Toronto Extremity Salvage (TESS) scores. The median followup was 58 months (range, 24-192 months).

RESULTS

Extended curettage was the only modality of treatment for all patients including all subsequent local recurrences. Nine had local recurrence, three of which had a second local recurrence; one had a third recurrence. Ultimately all patients were in remission at last followup. The local recurrence rate was 29% and appeared higher compared with recent series of all anatomic sites. The mean final MSTS and TESS scores were 91% (range, 71%-100%) and 88% (range, 35%-100%), respectively.

CONCLUSIONS

Extended curettage was the unique modality of surgical treatment for all tumors. We found the incidence of local recurrence higher than that reported for other locations but recurrences were manageable with repeated curettage. Complications and function appeared better than those reported for series of ankle fusion or reconstruction for bone tumors.

Parathyroid hormone-related protein (PTHrP) modulates adhesion, migration and invasion in bone tumor cells

Parathyroid-hormone-related protein (PTHrP) has been shown to be an important factor in osteolysis in the setting of metastatic carcinoma to the bone. However, PTHrP may also be central in the setting of primary bone tumors. Giant cell tumor of bone (GCT) is an aggressive osteolytic bone tumor characterized by osteoclast-like giant cells that are recruited by osteoblast-like stromal cells. The stromal cells of GCT are well established as the only neoplastic element of the tumor, and we have previously shown that PTHrP is highly expressed by these cells both in vitro and in vivo. We have also found that the stromal cells exposed to a monoclonal antibody to PTHrP exhibited rapid plate detachment and quickly died in vitro. Therefore, PTHrP may serve in an autocrine manner to increase cell proliferation and promote invasive properties in GCT. The purpose of this study was to use transcriptomic microarrays and functional assays to examine the effects of PTHrP neutralization on cell adhesion, migration and invasion. Microarray and proteomics data identified genes that were differentially expressed in GCT stromal cells under various PTHrP treatment conditions. Treatment of GCT stromal cells with anti-PTHrP antibodies showed a change in the expression of 13 genes from the integrin family relative to the IgG control. Neutralization of PTHrP reduced cell migration and invasion as evidenced by functional assays. Adhesion and anoikis assays demonstrated that although PTHrP neutralization inhibits cell adhesion properties, cell detachment related to PTHrP neutralization did not result in associated cell death, as expected in mesenchymal stromal cells. Based on the data presented herein, we conclude that PTHrP excreted by GCT stromal cells increases bone tumor cell local invasiveness and migration.

Primary perivascular epithelioid cell neoplasm (PEComa) of bone: report of two cases and review of the literature

Primary perivascular epithelioid cell neoplasms (PEComas) of bone are rare mesenchymal tumors. Histologically, they are composed predominantly of perivascular epithelioid cells and have the capacity to metastasize. PEComas have been reported within intra-abdominal and intra-pelvic organs. To the best of our knowledge, only seven primary PEComas of bone have been described in the English literature. We present two cases of PEComa of bone, one arising from the distal fibula and one from the acetabulum. Both were treated by surgical excision and one also received adjuvant chemotherapy.

Transcriptomic and proteomic analyses in bone tumor cells: Deciphering parathyroid hormone-related protein regulation of the cell cycle and apoptosis

Giant cell tumor of bone (GCT) is an aggressive skeletal tumor characterized by local bone destruction, high recurrence rates, and metastatic potential. Previous works in our laboratory, including functional assays, have shown that neutralization of parathyroid hormone-related protein (PTHrP) in the cell environment inhibits cell proliferation and induces cell death in GCT stromal cells, indicating a role for PTHrP in cell propagation and survival. The objective of this study was to investigate the global gene and protein expression patterns of GCT cells in order to identify the underlying pathways and mechanisms of neoplastic proliferation provided by PTHrP in the bone microenvironment. Primary stromal cell cultures from 10 patients with GCT were used in this study. Cells were exposed to optimized concentrations of either PTHrP peptide or anti-PTHrP neutralizing antiserum and were analyzed with both cDNA microarray and proteomic microarray assays in triplicate. Hierarchical clustering and principal component analyses confirmed that counteraction of PTHrP in GCT stromal cells results in a clear-cut gene expression pattern distinct from all other treatment groups and the control cell line human fetal osteoblast (hFOB). Multiple bioinformatics tools were used to analyze changes in gene/protein expression and identify important gene ontologies and pathways common to this anti-PTHrP-induced regulatory gene network. PTHrP neutralization interferes with multiple cell survival and apoptosis signaling pathways by triggering both death receptors and cell cycle-mediated apoptosis, particularly via the caspase pathway, TRAIL pathway, JAK-STAT signaling pathway, and cyclin E/CDK2-associated G1/S cell cycle progression. These findings indicate that PTHrP neutralization exhibits anticancer potential by regulating cell-cycle progression and apoptosis in bone tumor cells, with the corollary being that PTHrP is a pro-neoplastic factor that can be targeted in the treatment of bone tumors.

Hyperthermic isolated limb perfusion for extremity soft tissue sarcomas: systematic review of clinical efficacy and quality assessment of reported trials

BACKGROUND AND OBJECTIVES

Extremity soft tissue sarcomas (STS) are managed with radiotherapy and limb-sparing surgery however aggressive or recurrent cases require amputation. Hyperthermic isolated limb perfusion (HILP) has been proposed as an alternative. Our aim was to systematically review phase II HILP trials, assess tumor response, limb salvage (LS), and quality of scientific publications on this technique.

METHODS

We conducted a literature search of electronic databases (MEDLINE, EMBASE, Scopus, Cochrane Library) and clinical trial registries for phase II HILP trials on non-resectable extremity STS. Outcomes of interest were complete response (CR), partial response (PR), and LS rates. Quality of published trials was assessed using a quality checklist.

RESULTS

Of 518 patients across 12 studies, 408 had some response (CR or PR), and 428 had the limb spared. Median CR, PR, and LS rates were 31%, 53.5%, and 82.5%, respectively. Median Wieberdink loco-regional toxicity rates were 3.8%, 45.5%, 17%, 1%, and 0% for levels 1-5, respectively. No trial fulfilled either all ideal or essential quality criteria. Seven trials did not include statistical methodology.

CONCLUSION

HILP seems effective in treating advanced extremity STS. However, poor publication quality hinders results validity. Technical and methodological standardization, well-designed, multi-institutional trials are warranted.

Adverse Effect of Older Age on the Recurrence of Soft Tissue Sarcoma of the Extremities and Trunk

Purpose

To examine the effect of age on the recurrence of soft tissue sarcoma in the extremities and trunk.

Patients and Methods

This was a multicenter study that included 2,385 patients with median age at surgery of 57 years. The end points considered were local recurrence and metastasis. Cox proportional hazards models were used to estimate hazard ratios across the age ranges with and without adjustment for known confounding factors.

Results

Older patients presented with tumors that were larger (P < .001) and of higher grade (P < .001). The proportion of positive margins increased significantly as patients age (P < .001), but radiation therapy was relatively underused in patients older than age 60 years. The 5-year cumulative incidences of local recurrence were 7.2% (95% CI, 4% to 11.7%) for patients age 30 years or younger and 12.9% (95% CI, 9.1% to 17.5%) for patients age 75 years or older. The corresponding 5-year cumulative incidences of metastasis were 17.5% (95% CI, 12.1% to 23.7%) and 33.9% (95% CI, 28.1% to 39.8%) for the same groups. Regression models showed that age was significantly associated with local recurrence (P < .001) and metastasis (P < .001) in nonadjusted models. After adjusting for imbalance in presentation and treatment variables, age remained significantly associated with local recurrence (P = .031) and metastasis (P = .019).

Conclusion

Older patients have worse outcomes because they tend to present with worse tumors and are treated less aggressively. However, there remained a significant increase in the risk of both local and systemic recurrence associated with increasing age that could not be explained by tumor or treatment characteristics.

Initial McGill experience with fluorodeoxyglucose pet/ct staging of soft-tissue sarcoma

BACKGROUND

Soft-tissue sarcoma spreads predominantly to the lung. The frequency with which positron-emission tomography (pet) detects metastases not already obvious by chest computed tomography (ct) or clinical examination is currently unclear.

METHODS

We retrospectively identified cases of soft-tissue sarcoma. Ewing sarcoma, rhabdomyosarcoma, and gastrointestinal stromal tumour were excluded, as were cases in which patients underwent imaging for follow-up, response assessment, or recurrence. Patients all had undergone diagnostic chest ct as part of their staging. Directed studies were requested to follow up on abnormal findings in the clinical history or physical examination. All charts and pre-treatment imaging were reviewed retrospectively.

RESULTS

From 2004 to 2008, 75 patients met the criteria for the present review. Their median age was 51 years. In 21% of cases, the primary tumour had been removed (by excisional biopsy or unplanned excision) before staging. Of the previously unresected primary tumours, 97% were avid for fluorodeoxyglucose. Of all tumours, 81% were intermediate or high grade (Fédération Nationale des Centres de Lutte Contre le Cancer grades 2-3). The primary tumour was stage T2b in 69% of cases. The most common primary site was a lower extremity (55%). The most common pathologic diagnoses were leiomyosarcoma (21%), liposarcoma (19%), and synovial sarcoma (17%). At the end of staging, 17% of patients were considered to have metastatic disease. Imaging by pet was negative for distant disease in 64 of the 75 cases. In 7 of the 64 cases, metastatic disease was evident on chest ct (negative predictive value: 88%). Imaging by pet was positive in 8 cases, with 5 of those already known to have metastases, 2 having pathologically proven false positives, and 1 being a new finding of a pulmonary metastasis (positive predictive value: 75%). The pet imaging was indeterminate in 3 patients (none of whom subsequently developed metastatic disease). Two incidental benign parotid tumours were found. Overall, only 1 patient was upstaged as a result of pet imaging (1.3%). In addition, pet did not alter the management of patients already know to have M1 disease (no new organ sites identified).

CONCLUSIONS

Although pet may be helpful in specific circumstances, routine use of fluorodeoxyglucose pet imaging for detection of metastatic disease as part of the initial staging of soft-tissue sarcoma added little to imaging by chest ct and was unlikely to alter management in our series.

FDG PET/CT imaging in primary osseous and soft tissue sarcomas: a retrospective review of 212 cases

PURPOSE

The aims of this study are to evaluate the sensitivity of FDG PET/CT for detection of soft tissue and osseous sarcomas on the basis of FDG avidity.

METHODS

We retrospectively evaluated 212 consecutive patients with known soft tissue or osseous sarcoma who had undergone a FDG PET/CT study for the initial staging or assessment of recurrence of disease. The maximum standardized uptake value (SUVmax) of each primary and/or most intense metastatic lesion was measured and compared with the histological data provided in the final pathological reports. An SUVmax of 2.5 or greater was considered positive for our analysis.

RESULTS

Sufficient histopathological data were available for 160 soft tissue sarcomas and 52 osseous sarcomas. FDG PET/CT detected 93.9% of all sarcomas with a sensitivity of 93.7% for soft tissue sarcomas and 94.6% for osseous sarcomas. The sensitivities of the most common sarcoma histologies were 100% for leiomyosarcomas, 94.7% for osteosarcomas, 100% for Ewing's sarcomas, 88.9% for liposarcomas, 80.0% for synovial sarcomas, 100% for gastrointestinal stromal tumors, 87.5% for malignant peripheral nerve sheath tumors, 100% for fibroblastic and myoblastic sarcomas, and 100% for malignant fibrohistiocytic tumors. The receiver-operating characteristic curve revealed an area under the curve of 94% for the discrimination of low-grade and high-grade sarcomas imaged for initial staging by FDG PET/CT.

CONCLUSION

The combined metabolic and morphological information of FDG PET/CT imaging allows high sensitivity for the detection of various sarcomas and accurate discrimination between newly diagnosed low-grade and high-grade sarcomas.

PTHrP induces autocrine/paracrine proliferation of bone tumor cells through inhibition of apoptosis

Giant Cell Tumor of Bone (GCT) is an aggressive skeletal tumor characterized by local bone destruction, high recurrence rates and metastatic potential. Previous work in our lab has shown that the neoplastic cell of GCT is a proliferating pre-osteoblastic stromal cell in which the transcription factor Runx2 plays a role in regulating protein expression. One of the proteins expressed by these cells is parathryroid hormone-related protein (PTHrP). The objectives of this study were to determine the role played by PTHrP in GCT of bone with a focus on cell proliferation and apoptosis. Primary stromal cell cultures from 5 patients with GCT of bone and one lung metastsis were used for cell-based experiments. Control cell lines included a renal cell carcinoma (RCC) cell line and a human fetal osteoblast cell line. Cells were exposed to optimized concentrations of a PTHrP neutralizing antibody and were analyzed with the use of cell proliferation and apoptosis assays including mitochondrial dehydrogenase assays, crystal violet assays, APO-1 ELISAs, caspase activity assays, flow cytometry and immunofluorescent immunohistochemistry. Neutralization of PTHrP in the cell environment inhibited cell proliferation in a consistent manner and induced apoptosis in the GCT stromal cells, with the exception of those obtained from a lung metastasis. Cell cycle progression was not significantly affected by PTHrP neutralization. These findings indicate that PTHrP plays an autocrine/paracrine neoplastic role in GCT by allowing the proliferating stromal cells to evade apoptosis, possibly through non-traditional caspase-independent pathways. Thus PTHrP neutralizing immunotherapy is an intriguing potential therapeutic strategy for this tumor.

Case series. Soft-tissue sarcoma of the foot

BACKGROUND

We reviewed cases of soft-tissue sarcoma of the foot to gain insight into the presentation, treatments and outcomes for this rare disease and to determine whether limb-salvage surgery yields reasonable functional and oncological outcomes.

METHODS

We reviewed the cases of 16 patients treated by 2 of us (R.T. and M.I.) for soft-tissue sarcoma of the foot over a 15-year period. We extracted the following information from each patient's medical record: disease status at presentation, prior treatment, histological diagnosis, American Joint Committee on Cancer (AJCC) stage, details of treatment, oncological outcome and functional outcome. Functional outcome was assessed with the Toronto Extremity Salvage Score (TESS) and the Musculoskeletal Tumor Society (MSTS 1987).

RESULTS

Follow-up averaged 6 (range 2–15) years. Eight patients presented after unplanned excision. Histological diagnosis was synovial sarcoma for 7 of 16 patients.The tumours were evenly distributed among the hindfoot, midfoot and forefoot. Most patients (n = 13) presented with AJCC stage II or III disease. Amputation was necessary for 3 patients, whereas limb salvage was possible for the other 13. Free tissue transfer (n = 9) and radiation therapy (n = 12) were used in most cases. Surgical margins were microscopically positive in 4 of the 13 patients treated with limb salvage.Local disease recurred in 2 patients. Lung metastases occurred in 4 patients. At last follow-up, 11 of 16 patients were alive without disease, 2 with disease and 3 had died of their disease. Functional assessment with MSTS 1987 and the TESS averaged 28%and 90%, respectively, after limb salvage.

CONCLUSION

In this series, we found that, first, patients frequently presented after unplanned excision, and this may have led to worse oncological outcomes compared with patients who presented primarily. Second, limb salvage was usually possible, but it required accepting marginal resections, relying on free tissue transfer to obtain coverage and using radiation therapy to obtain local control. Third, this combination yielded an acceptable local control rate and very good functional outcomes.

The efficacy of chemical adjuvants on giant-cell tumour of bone. An in vitro study

Various chemicals are commonly used as adjuvant treatment to surgery for giant-cell tumour (GCT) of bone. The comparative effect of these solutions on the cells of GCT is not known. In this study we evaluated the cytotoxic effect of sterile water, 95% ethanol, 5% phenol, 3% hydrogen peroxide (H(2)O(2)) and 50% zinc chloride (ZnCI(2)) on GCT monolayer tumour cultures which were established from six patients. The DNA content, the metabolic activity and the viability of the cultured samples of tumour cells were assessed at various times up to 120 hours after their exposure to these solutions. Equal cytotoxicity to the GCT monolayer culture was observed for 95% ethanol, 5% phenol, 3% H(2)O(2) and 50% ZnCI(2). The treated samples showed significant reductions in DNA content and metabolic activity 24 hours after treatment and this was sustained for up to 120 hours. The samples treated with sterile water showed an initial decline in DNA content and viability 24 hours after treatment, but the surviving cells were viable and had proliferated. No multinucleated cell formation was seen in these cultures. These results suggest that the use of chemical adjuvants other than water could help improve local control in the treatment of GCT of bone.

Local recurrence after initial multidisciplinary management of soft tissue sarcoma: is there a way out?

BACKGROUND

Multimodality treatment of primary soft tissue sarcoma by expert teams reportedly affords a low incidence of local recurrence. Despite advances, treatment of local recurrence remains difficult and is not standardized.

QUESTIONS/PURPOSES

We (1) determined the incidence of local recurrence from soft tissue sarcoma; (2) compared characteristics of the recurrent tumors with those of the primary ones; (3) evaluated local recurrences, metastases and death according to treatments; and (4) explored the relationship between the diagnosis of local recurrence and the occurrence of metastases.

METHODS

From our prospective database, we identified 618 soft tissue sarcomas. Thirty-seven of the 618 patients (6%) had local recurrence. Leiomyosarcoma was the most frequent diagnosis (eight of 37). The mean delay from original surgery was 22 months (range, 2-75 months). Mean size was 4.8 cm (range, 0.4-28.0 cm). Median followup after local recurrence was 16 months (range, 0-98 months).

RESULTS

Recurrent tumors had a tendency toward becoming deeper seated and higher graded. Nineteen of the 37 patients with recurrence underwent limb salvage (nine free flaps) and six had an amputation. Twenty-two (59%) had metastases, including 10 occurring after the local recurrence event at an average delay of 21 months (range, 1-34 months). Six patients developed additional local recurrences, with no apparent difference in risk between amputation (two of six) and limb salvage (four of 19).

CONCLUSIONS

Patients with a local recurrence of a soft tissue sarcoma have a poor prognosis. Limb salvage and additional radiotherapy remain possible but with substantial complications. Amputation did not prevent additional local recurrence or death.

Evidence for the role of matrix metalloproteinase-13 in bone resorption by giant cell tumor of bone

Giant cell tumor of bone (GCT) is an aggressively osteolytic primary bone tumor that is characterized by the presence of abundant multinucleated osteoclast-like giant cells, hematopoietic monocytes, and a distinct mesenchymal stromal cell component. Previous work in our laboratory has shown that matrix metalloproteinase (MMP)-13 is the principal proteinase expressed by the stromal cells of GCT. The release of cytokines, particularly interleukin-1beta, by the giant cells of GCT acts on stromal cells to stimulate a surge in MMP-13 secretion. The purpose of this study was to determine the bone resorption capabilities of the cellular elements of GCT and the significance of the MMP-13 expression involved in GCT bone resorption. We present a 3-dimensional histomorphometric technique developed to analyze resorption pit depth and yield an accurate measurement of bone resorption with a direct physical view of lacunae on bone slices. In this study, we demonstrate that the mesenchymal stromal cells and the multinucleated giant cells of GCT are independently capable of bone resorption. However, coculture of these 2 cell fractions shows a synergistic increase in bone resorption. In addition, inhibition of MMP-13 reduces resorptive activity of the cells indicating that MMP-13 likely plays an important role in this tumor. This cell-cell cooperation involves giant cell-derived cytokine up-regulation of MMP-13 in the stromal cells, which in turn assists the giant cells in bone resorption. Future research will involve elucidation of the role of cell-cell/matrix communication pathways in bone resorption and tumorigenesis in GCT.

Matrix Metalloproteinase Activity in the Stromal Cell of Giant Cell Tumor of Bone

Giant cell tumor of bone (GCT) is a destructive and potentially metastatic bone tumour in which the characteristic giant cells have classically been considered the culprits in bone destruction. However, the neoplastic element of the tumour consists of propagative osteoblast-like stromal cells that may play a role in bone resorption. The objectives of this study were to determine the expression and activity of the gelatinases, matrix metalloproteinase (MMP)-2 and -9, in GCT stromal cells, and to determine if these cells have bone-resorbing capabilities. We performed immunohistochemistry on clinical specimens, and real-time polymerase chain reaction (PCR) and zymography on cell lysates and conditioned media from cultured clinical GCT specimens in order to evaluate the expression and activity of MMP-2 and-9 in GCT stromal cells. Our results support the fact that GCT stromal cells express MMP-2 and MMP-9 and are capable of gelatin degradation in vitro. These cells may therefore play a role in bone destruction in GCT.

PET/CT for radiotherapy treatment planning in patients with soft tissue sarcomas

PURPOSE

To study the possibility of incorporating positron emission tomography/computed tomography (PET/CT) information into radiotherapy treatment planning in patients with high-grade soft tissue sarcomas (STS).

METHODS AND MATERIALS

We studied 17 patients treated with preoperative radiotherapy at our institution from 2005 to 2007. All patients had a high-grade STS and had had a staging PET/CT scan. For each patient, an MRI-based gross tumor volume (GTV), considered to be the contemporary standard for radiotherapy treatment planning, was outlined on a T1-gadolinium enhanced axial MRI (GTV(MRI)), and a second set of GTVs were outlined using different threshold values on PET images (GTV(PET)). PET-based target volumes were compared with the MRI-based GTV. Threshold values for target contouring were determined as a multiple (from 2 to 10 times) of the background soft tissue uptake values (B) sampled over healthy tissue.

RESULTS

PET-based GTVs contoured using a threshold value of 2 or 2.5 most closely resembled the GTV(MRI) volumes. Higher threshold values lead to PET volumes much smaller than the GTV(MRI). The standard deviations between the average volumes of GTV(PET) and GTV(MRI) ratios for all thresholds were large, ranging from 36% for 2 xB up to 93% for 10 xB. Maximum uptake-to-background ratio correlated poorly with the maximum standardized uptake values.

CONCLUSIONS

It is unlikely that PET/CT will make a significant contribution in GTV definition for radiotherapy treatment planning in patients with STS using threshold methods on PET images. Future studies will focus on molecular imaging and tumor physiology.

Outcomes in patients with popliteal sarcomas

BACKGROUND

Soft-tissue sarcoma involving the popliteal fossa remains challenging because it is difficult to achieve wide margins with limb salvage in this location. Adjuvant therapy is frequently necessary, and limb function can be adversely affected. We reviewed our experience with these tumours.

METHODS

Our prospective tumour database served to identify all patients with popliteal sarcomas treated at the McGill University Health Centre and the Maisonneuve-Rosemont Hospital between 1994 and 2005. We assessed oncologic and functional outcomes as well as complications.

RESULTS

Our study included 18 patients (12 women and 6 men). The mean age was 54 (range 16-84) years. The mean duration of follow-up was 55 (range 4-126) months. Frequent histologic diagnoses were liposarcoma (n = 6), synovial sarcoma (n = 4) and leiomyosarcoma (n = 3). Tumour size varied from 2 to 21 cm (median 11 cm). American Joint Committee on Cancer staging was as follows: 4 patients had stage IIa disease, 3 patients had stage IIb, 10 patients had stage III and 1 patient had stage IV disease. Treatment consisted of limb salvage in 15 patients and amputation in 3. Fourteen patients had radiotherapy, 4 had chemotherapy, and 3 needed partial sciatic nerve resection. Margins were negative in 7 of 18 patients and microscopically positive in 11 patients. Complications included wound infections in 3 patients and thrombophlebitis in 2 patients. Of the patients undergoing limb-salvaging procedures, 1 experienced local recurrences after limb salvage (7%), and 5 experienced lung metastases (20%). Local recurrence was always associated with positive margins, whereas metastases occurred only in patients without local recurrence. The mean Musculoskeletal Tumor Society 1987 score was 33 (range 24-35). The mean Toronto Extremity Salvage Score results was 82.4 (range 63.8-100). At latest follow-up, 6 patients had died of disease, 1 was alive with disease, and 11 (61%) patients remained free of disease.

CONCLUSION

Despite the high rate of microscopically positive margins, the local recurrence rate was 7%. Amputation did not prevent death. We found function to be good to excellent in most patients who had limb-salvaging surgery.

Low-dose chemotherapy for extra-abdominal desmoid tumor

OBJECTIVE

To assess the outcome of patients with extra-abdominal desmoid tumor treated with low dose chemotherapy (methotrexate and vinblastine) both for tumor response and treatment related toxicity.

METHODS

We retrospectively reviewed the outcome of 12 patients who underwent low dose chemotherapy for extra abdominal desmoid of different locations. The study took place in the McGill University Health Center, Montreal, Canada between 1996 and 2003. We evaluated the patients for their compliance, tumor response, complications of treatment, and impact of treatment on symptoms. There were 7 females and 5 males with a mean age of 46 years.

RESULTS

Disease related morbidity included pain in 7 patients, functional limitation in 7 and cosmetic defects in 3. The mean tumor size was 11 cm (3-20 cm). The mean follow-up was 43 months (15-71 months). Chemotherapy was administered weekly. Complications were significant. Only 2 patients did not experience the toxicity. According to Response Evaluation Criteria in Solid Tumors, 6 tumors showed a partial response and 6 remained stable. None showed progression. Of the 7 patients who had painful tumors, 6 achieved significant symptom relief. Function was improved in 3 and restored to normal in 4. Cosmesis was improved in 2 of the 3. At latest follow-up, tumors remained stable in 8, one has markedly regressed and 3 exhibited progression at an average of 54 months. Only one patient required surgery. The only long term side effect was a sensory peripheral neuropathy.

CONCLUSION

Low dose chemotherapy was found to be a valuable adjunct to prevent local progression and improve symptoms.

Giant cell tumor of bone express p63

p63 contributes to skeletal development and tumor formation; however, little is known regarding its activity in the context of bone and soft tissue neoplasms. The purpose of this study was to investigate p63 expression in giant cell tumor of bone and to determine whether it can be used to discriminate between other giant cell-rich tumors. Seventeen cases of giant cell tumor of bone were examined to determine the cell type expressing p63 and identify the isoforms present. Total RNA or cell protein was extracted from mononuclear- or giant cell-enriched fractions or intact giant cell tumor of bone and examined by RT-PCR or western blot, respectively. Immunohistochemistry was used to evaluate p63 expression in paraffin embedded sections of giant cell tumor of bone and in tumors containing multinucleated giant cells, including: giant cell tumor of tendon sheath, pigmented villonodular synovitis, aneurysmal bone cyst, chondroblastoma, and central giant cell granuloma. The mononuclear cell component in all cases of giant cell tumor of bone was found to express all forms of TAp63 (alpha, beta, and gamma), whereas only low levels of the TAp63 alpha and beta isoforms were detected in multinucleated cells; DeltaNp63 was not detected in these tumors. Western blot analysis identified p63 protein as being predominately localized to mononuclear cells compared to giant cells. This was confirmed by immunohistochemical staining of paraffin-embedded tumor sections, with expression identified in all cases of giant cell tumor of bone. Only a proportion of cases of aneurysmal bone cyst and chondroblastoma showed p63 immunoreactivity whereas it was not detected in central giant cell granuloma, giant cell tumor of tendon sheath, or pigmented villonodular synovitis. The differential expression of p63 in giant cell tumor of bone and central giant cell granuloma suggest that these two tumors may have a different pathogenesis. Moreover, p63 may be a useful biomarker to differentiate giant cell tumor of bone from central giant cell granuloma and other giant cell-rich tumors, such as giant cell tumor of tendon sheath and pigmented villonodular synovitis.

Tumors masquerading as hematomas

Suboptimal patient management can occur when malignant soft tissue tumors with internal hemorrhage masquerade as simple hematomas. We retrospectively reviewed 31 patients with malignancies who had diagnostic delays averaging 6.7 months (range, 1.0-49.3 months). The diagnoses included soft tissue sarcomas (27), metastatic cancers (three), and lymphoma (one). History of subcutaneous ecchymosis was positive in only five patients (three of whom had trauma), negative in 18, and unknown in eight. Ecchymosis was present in two patients, absent in 20, and unknown in nine. Previous treatments included observation and reassurance (21), aspiration (11), incision and drainage (10), unplanned resections (seven), physical therapy (seven), medication administration (six), and arthroscopy (one). Interpretations of initial MRI (21) and ultrasound (four) did not raise suspicion of underlying cancers. Traumatic hemorrhage usually causes subcutaneous ecchymosis. However, intratumoral hemorrhage often is contained by a pseudocapsule, which prevents fascial plane tracking and subcutaneous ecchymosis, thus providing a diagnostic clue. Magnetic resonance imaging and ultrasound studies may not accurately diagnose questionable lesions. Diagnostic delay or inappropriate treatment may result if patients do not receive appropriate followup, biopsy (usually open), or referral whenever the diagnosis is in doubt.

Experience with cemented large segment endoprostheses for tumors

Published reports dealing with tumor prosthesis have yet to establish a clear advantage of using either cemented or cementless implants. We examined the outcome and complications with modular cemented implants in 135 patients identified from our database to strengthen the argument for routine use of cemented constructs. The minimum followup was 1.4 months (mean, 57 months; median, 47 months; range, 1.4-157 months). The majority of patients (104) had sarcoma. The complications included: 11 infections, three of which underwent amputation and one a stem revision; eight local recurrences, five of which underwent amputation; three hip dislocations; and three incidents of shoulder instability. One periprosthetic femur fracture was stabilized operatively. There was no aseptic loosening or stem fracture. The 5-year survival rates for distal femoral and proximal humeral replacements were 84% and 70%; the 10-year survival rates were 79% and 59%. The 5-year survival rates for proximal femur and proximal tibia replacements were 78% and 37%. Average Musculoskeletal Tumor Society 1987 scores and Toronto Extremity Salvage Scores were 21.5 and 73% for proximal femur, 28.1 and 67% for distal femur, and 21 and 78% for proximal humerus. The survival of the endoprostheses related to site of bone resection. Cemented constructs of modern design in the context of tumor surgery provide good short-term results.

Cemented rotating hinge endoprosthesis for limb salvage of distal femur tumors

We retrospectively ascertained the outcomes and complications with a cemented rotating hinge implant. Implant failure was defined as amputation of the affected limb and revision of part or all of the components. We included 77 consecutive distal femoral replacements performed between 1989 and 2004. The mean age was 42 years (range, 12-87 years) and the mean length of followup was 52 months (range, 1.5-157 months). Five-year implant survival was 84% and 10-year survival was 79%. There were 67 bone sarcomas, two soft tissue sarcomas and eight metastatic carcinomas. At followup, 54 patients had no evidence of disease, 16 were alive with disease, and seven were dead from disease. Six patients had deep infection, two of which required amputations. There were five local recurrences; three needed amputation and two soft-tissue excisions only. Three patients sustained a tibial bearing fracture and one required replacement of loose bumper. No revision was performed for stem loosening, stem fracture, or bushing wear. Musculoskeletal Tumor Society 1987 scores averaged 30 and Toronto Extremity Salvage Scores averaged 77.6 at latest followup. Cemented endoprosthesis is a reliable procedure after resection of the distal femur for tumors.

LEVEL OF EVIDENCE

Therapeutic study, level IV (case series).

Endothelin-1 (ET-1) promotes MMP-2 and MMP-9 induction involving the transcription factor NF-kappaB in human osteosarcoma

In the present study, we have investigated the effect of (i) ET-1 (endothelin-1) and its precursor, big ET-1, on MMP (matrix metalloproteinase)-2 and MMP-9 synthesis and activity in osteosarcoma tissue, and (ii) ET-1 receptor antagonists on cell invasion. Using Western blotting, zymography, RT-PCR (reverse transcription-PCR), immunohistochemistry, immunofluorescence and Northern blotting, we have shown that ET-1 and ET-1 receptors (ET(A) and ET(B)) were expressed in these cells. Additionally, we have demonstrated that ET-1 markedly induced the synthesis and activity of MMP-2, which was significantly increased when compared with MMP-9. Furthermore, inhibition of NF-kappaB (nuclear factor kappaB) activation blocked MMP-2 production and activity, indicating the involvement of NF-kappaB, a ubiquitous transcription factor playing a central role in the differentiation, proliferation and malignant transformation. Since ET-1 acts as an autocrine mediator through gelatinase induction and because inhibition of ET(A) receptor is beneficial for reducing both basal and ET-1-induced osteosarcoma cell invasion, targeting this receptor could be an attractive therapeutic alternative for the successful treatment of osteosarcoma.

Primary hyperparathyroidism and malignancy: "studies by nature"

The American Food and Drug Administration approval of parathyroid hormone (PTH) administration for osteoporosis as well as the possibility for its future therapeutic applications requires an examination of the suggested association between PTH and cancer, particularly osteosarcomas. The objective was to evaluate such a connection by collecting observational data from two groups of patients, designated as "studies by nature". Cohort 1: Medical records of all patients with primary hyperparathyroidism that were treated in a referral center during a 12-year period were retrospectively reviewed for malignancy before, at the time or after diagnosis. Cohort 2: Records of patients with osteosarcomas that were treated in referral centers during 15 years were retrospectively reviewed for hyperparathyroidism, as indicated by history or laboratory results. There were 582 patients with primary hyperparathyroidism. While 56 (9.6%) had malignancy, 47 (8%) developed cancer after diagnosis with hyperparathyroidism during 6.1 years of documentation. This rate did not exceed the incidence of developing cancer among the general population. Although thyroid cancer was about 4 times the incidence in the general population, this may be attributed to a high level of detection while work-up, treating and following the parathyroid disease. None had osteosarcoma. None of the 126 patients with osteosarcoma had documentation of primary hyperparathyroidism or had biochemical evidence of hyperparathyroidism. No obvious association was found between primary hyperparathyroidism and cancer. Similarly, there was no demonstrable relationship between osteosarcomas and hyperthyroidism biochemical stigmata. Since PTH may contribute to tumor invasiveness, screening for existing neoplasms, especially prostate and breast, before PTH treatment may be of importance.

Giant cell tumor of bone

Giant cell tumor is a common benign bone tumor that possesses specific features including location at the end of long bone, a strong tendency toward local recurrence, and the rare capacity to metastasize to the lungs. Preferred treatment usually consists of extensive curettage and filling of the cavity with bone graft or cement. Debate still exists about the usefulness of local adjuvant treatment. Functional outcome is usually very good.

Iliosacral resection for primary bone tumors: is pelvic reconstruction necessary?

Iliosacral resection for primary bone tumors creates a large unstable pelvic ring defect, the treatment of which remains controversial. We did this study to determine if skeletal reconstruction of such defects is necessary. Sixteen patients whose data were collected prospectively had iliosacral resection with a minimum followup of 12 months. The surgical and functional results of patients who had skeletal reconstruction (n = 4) were compared with the results of patients who did not have iliosacral repair (n = 12) using a case-control design. Function was evaluated by assessing impairment using the Musculoskeletal Tumor Society 1987 and 1993 rating scales, and disability was measured using the Toronto Extremity Salvage Score. Although all four iliosacral arthrodeses initially healed, one allograft used for reconstruction fractured and another was removed because of progressive lumbosacral spinal instability. Patients treated without pelvic reconstruction had fewer operative complications. Although the Toronto Extremity Salvage Score and the Musculoskeletal Tumor Society 1987 and 1993 scores were similar for both patient groups, those patients who were treated without reconstruction were less likely to require the use of an ambulatory assistive device, less likely to require narcotics or have chronic pain, and more likely to return to work. These results suggest that reconstruction of the skeletal defect to restore pelvic stability after iliosacral resection is not mandatory.

LEVEL OF EVIDENCE

Therapeutic study, Level III-1 (case-control study). See the Guidelines for Authors for a complete description of levels of evidence.

Outcome after pelvic sarcoma resection reconstructed with saddle prosthesis

We retrospectively reviewed 27 patients who had saddle prosthetic reconstruction for pelvic sarcoma from 1991 to 2001 with a mean followup of 45 months. Functional outcome was assessed with Musculoskeletal Tumor Society Scores of 1987 and 1993 and the Toronto Extremity Salvage score. Survival, recurrences, and complications were recorded. Seven (26%) patients had Type II (periacetabular) pelvic resection and 20 had Types II and III (periacetabular and pubis) pelvic resection. Eleven patients had chemotherapy treatment. None received radiation therapy. At final followup 14 patients were free of disease, 11 patients died, and two patients were alive with disease. The survival rate was 60%. Twenty-two percent had local recurrence, and 22% had metastasis. The mean Musculoskeletal Tumor Society Score 93 score in 17 patients was 50.8% +/- 21.7%, the mean Musculoskeletal Tumor Society Score 87 score was 15.3 +/- 6.1, and the mean Toronto Extremity Salvage score was 64.4% +/- 17.2%. Infection occurred in 10 patients; six were deep infections. There were five nerve palsies. Heterotopic ossification occurred in 10 patients, fracture occurred in six patients, and dislocation occurred in six patients. Limb shortening was progressive until it stabilized at 12 months, and ultimately ranged between 1 and 6 cm. Five patients were retired, five had full-time employment, and six were disabled. Reconstruction with the saddle prosthesis after resection for pelvic sarcoma is associated with substantial morbidity. However, the functional results seem to confer an advantage when compared with the considerable disability incurred after hemipelvectomy.

LEVEL OF EVIDENCE

Therapeutic study, Level IV-1 (case series without control group). See the Guidelines for Authors for a complete description of levels of evidence.

Function and health status in surgically treated bone metastases

In a prospective study, we evaluated if surgery substantially improved functional and quality of life outcomes in patients with nonspinal bone metastases. Sixty-seven patients were followed up prospectively. The Short Form-36, the Musculoskeletal Tumor Society 1987 form, the Musculoskeletal Tumor Society 1993 form, and the Toronto Extremity Salvage Score were administered preoperatively and 6 weeks and 3 months postoperatively. Fifty percent of the patients had pathologic fractures. Intramedullary nailing was done in 36 patients, prosthetic replacement was done in 24 patients, and plating was done in five patients. The average postoperative survival was 8 months. At 6 weeks, 13 patients had died and seven were lost to followup. Twenty-one percent of patients had complications, although only 4.5% needed additional surgery. The patients' Musculoskeletal Tumor Society 1987 form, Musculoskeletal Tumor Society 1993 form, and Toronto Extremity Salvage Score scores improved at 6 weeks and 3 months postoperatively. There were no improvements in the Short Form-36 mental and physical summary scales of the patients. The number of patients using pain medication did not decrease. Patients had functional improvements after surgical treatment of bone metastases, even patients with a limited life expectancy. Future prospective studies should anticipate a high rate of attrition with this population from death and loss to followup.

LEVEL OF EVIDENCE

Prognostic study, Level I (high quality prospective study-all patients were enrolled at the same point in their disease with > or = 80% followup of enrolled patients). See the Guidelines for Authors for a complete description of levels of evidence.

Giant cell tumor of long bone: a Canadian Sarcoma Group study

A multicentric retrospective study of giant cell tumor of bone was conducted among Canadian surgeons. The hypothesis was that no differences would be found in health status, function, or recurrence rate irrespective to the nature of filling material or adjuvant used in patients treated with curettage. One hundred eighty-six cases were collected. There were 96 females and 90 males. The mean age of the patients was 36 years (range, 14-72 years), the minimum followup was 24 months, and the median followup was 60 months. Sixty-two percent of the tumors involved the knee region. One hundred fifty-eight were primary tumors and 28 were recurrences. Campanacci grading was as follows: Grade 1, seven patients; Grade 2, 100 patients; Grade 3, 76 patients; and unknown in three patients. Fifty-six patients had a pathologic fracture. Resection was done in 38 patients and 148 patients had curettage. The latter was supplemented with high speed burring in 135 patients, cement in 64 patients, various combinations of autograft or allograft bone in 61 patients, phenol in 37 patients, and liquid nitrogen in 10 patients. Structural allografts were used in 25 patients. The overall recurrence rate was 17%, 18% after curettage, and 16% after resection. Patients with primary tumors treated with curettage had a 10% recurrence rate. For recurrent lesions treated by curettage, the recurrence rate was 35%. The nature of the filling material used or the type of adjuvant method used or any combination of both failed to show any statistical impact on the recurrence risk. The results from the Musculoskeletal Tumor Society rating from 1987 were significantly lower in patients who sustained a displaced fracture. Results from the bodily pain section of the Short Form-36 also were found to be lower when a pathologic fracture was present. Results from the Musculoskeletal Tumor Society Rating 1987, the Short Form-36, and the Toronto Extremity Salvage Score did not show differences when either cement or bone graft were used after curettage.

Functional evaluation in distal femoral endoprosthetic replacement for bone sarcoma

A multicenter study of successfully treated patients (mean age, 36.7 years) with a minimum 1-year followup (average, 35.4 months) after distal femoral endoprosthetic replacement for bone sarcoma was done using the 1987 and 1993 versions of the Musculoskeletal Tumor Society, the Short Form-36, and the Toronto Extremity Salvage Score functional evaluation criteria. Fifty-six patients (28 women and 28 men) fulfilled the criteria. Thirty-one Kotz prostheses (fixed hinge, uncemented) and 25 Modular Replacement System Prostheses (rotating hinge, cemented) were used. Thirty-five patients walked without aids, 19 used a cane, and two used crutches or a walker. The Musculoskeletal Tumor Society 1987 mean score was 28.1. The Musculoskeletal Tumor Society 1993 mean score was 80.4. The Toronto Extremity Salvage Score mean was 81.6. The Short Form-36 Physical Component Score had a mean of 43.2 and Mental Component Score mean of 54.2. The two groups of implants were comparable, except for the length of bone resection. Multivariate regression analysis revealed that patient age, existence of a pathologic fracture, and type of prosthesis all significantly accounted for differences in functional outcome as measured by the Musculoskeletal Tumor Society 1993, the Toronto Extremity Salvage Score, and the Short Form-36 Physical Component Score scales. Although both implants provided satisfactory function, the Musculoskeletal Tumor Society 1993 and the Toronto Extremity Salvage Score results were significantly better with the Modular Replacement System prosthesis. The effect of possible differences among surgeons or institutions was not addressed.

Chondroblastoma

Chondroblastoma of the bone is a benign tumor that has well-characterized radiographic and histologic features. It tends to affect the epiphyseal ends of long bones in men during the second and third decades of life. The tumor is located more frequently at other sites in older patients. The treatment of choice is complete curettage with bone grafting, which in our series provided local control in 82% of patients at 2 years' follow-up. Recurrent tumors usually can be treated in the same manner.

Unstable intertrochanteric fracture of the femur. A prospective randomised study comparing anatomical reduction and medial displacement osteotomy

We conducted a prospective randomised trial to compare the results of anatomical reduction and medial displacement osteotomy in 127 consecutive patients with unstable intertrochanteric fractures, of whom 109 completed the study. After an average follow-up of 11 months, we found no significant differences in walking ability, social status or failure of fixation in the two groups. Postoperative complication rates and the early mortality rate were not significantly different, but operating time and blood loss were significantly higher in the osteotomy group. With the use of modern sliding hip screws, medial displacement osteotomy is rarely indicated for unstable intertrochanteric fractures.