Functional outcome in limb-salvage surgery for soft tissue tumours of the foot and ankle

Purpose. This paper describes the functional and oncologic outcome of 30 cases (in 29 patients) treated with limb-salvage surgery for localized soft tissue sarcoma (STS) or fibromatosis of the foot and ankle.Subjects. Patients were eligible for the study if they had a STS or fibromatosis in the distal one-third of the tibia or the foot such that ablative surgery would require a below-knee amputation; had no metastatic disease at presentation; and had a minimum of 2 years of follow-up.Methods. Function was prospectively evaluated using the modified Enneking functional rating scale (MSTS) at 3, 6, 12 months and at most recent follow-up. Premorbid work status and change following surgery, lower leg oedema, and the use of orthotics and ambulatory aids were consecutively assessed. Tumour characteristics were recorded and patients were followed for systemic and local recurrence.Results. Thirty-six consecutive cases were managed by a multi-disciplinary sarcoma team. Six patients underwent below-knee amputation due to extensive local disease, while 30 cases were treated with limb-salvage surgery. Of the patients treated with limb salvage, there were 19 high-grade sarcomas, five low-grade sarcomas and six cases of fibromatosis. Microscopically negative margins were achieved in 26 of 30 cases. Ten cases required bone excision, and eight patients needed free vascularized tissue flaps. Twenty-five patients received adjuvant radiotherapy. Seven patients had post-operative complications. At mean follow-up of 52 months (range 24-109 months), four patients had developed systemic recurrence. There was one local recurrence in a patient with fibromatosis, while another patient with fibromatosis developed recurrence a considerable distance from the surgical and radiation field. Mean scores on the MSTS were 27.5 (range 11-35), 29.9 (range 13-35), 31.4 (range 17-35) and 31.0 (range 13-35) at 3, 6, 12 months and at most recent follow-up, respectively. Eighty-five per cent of the patients scored good to excellent at their last visit. Twelve patients reported persistent pain with two continuing to require occasional narcotics. Six had persistent mild oedema. Four required shoe modifications and three continue to use a cane. Six patients were unable to return to their premorbid employment with the majority of these previously employed in jobs requiring physical labour or long periods of either standing or walking.Discussion. Thirty of 36 patients (83%) presenting with foot and ankle STS or fibromatosis were candidates for limb preservation. With excellent local control and good functional outcome demonstrated in this study, limb salvage should be a primary goal in the management of selected patients with STS and fibromatosis of the foot and ankle.

Symptoms and their Relationship to Disability Following Treatment for Lower Extremity Tumours

Purpose. The aims of this study were to describe the symptoms experienced by patients in the first year following treatment for lower extremity sarcoma by limb conservation and to describe the relationship between symptoms and physical disability.

Subjects. Eighty consecutive patients treated for primary bone or soft tissue sarcoma (STS) of the lower limb who were treated with limb preservation surgery.

Methods. Subjects were evaluated by questionnaire at 6 weeks, and 3, 6, and 12 months post surgery. They identified whether they experienced any of the following symptoms: pain, stiffness, fatigue, weakness, limited range of motion, or swelling.The Toronto Extremity Salvage Score (TESS), a measure of physical disability, was also completed. Frequency of symptoms over time was calculated and change was evaluated using the Cochrane test. The relationship of symptoms to disability was analyzed with regression methods.

Results. The mean age was 43.0, SD=20.4 with a gender ratio of 1:1. There were 38 bone tumours and 42 STS.The most frequently reported symptoms were: stiffness 48 (60%), weakness 41 (51%), fatigue 26 (33%), and pain 25 (31%) at 6 weeks. Stiffness and fatigue decreased and plateaued by 3 months. Complaints of weakness and pain continued to decrease over time. At 6 weeks, pain, stiffness, weakness and limited motion predicted disability in both univariate and multivariate analyses. At 12 months, pain, stiffness, fatigue, weakness and limited motion were significant predictors of the TESS in univariate analysis with only pain, stiffness and limited motion significant predictors in the multivariate model.

Discussion. Pain, stiffness, fatigue, weakness and limited motion are common symptoms with stiffness and weakness decreasing significantly over time. The symptoms predictive of disability differ between the acute and late phases of recovery.

A comparison of outcome of osteoarticular allograft reconstruction and shoulder arthrodesis following resection of primary tumours of the proximal humerus

Purpose. The purpose of this study was to compare the oncologic, reconstructive and functional outcomes of patients who underwent osteoarticular allograft reconstruction with those who underwent arthrodesis for a primary malignant bone tumour of the proximal humerus.

Patients. Eleven patients were treated with osteoarticular allograft reconstruction of the proximal humerus. Five of these reconstructions failed, necessitating revision to a secondary arthrodesis. Five patients underwent arthrodesis as a primary reconstruction, for a total of ten patients in the arthrodesis group.

Methods. End points included local and systemic disease recurrence, complications and functional outcome (measured using the 1987 and 1993 Musculoskeletal Tumour Society Rating Scales (MSTS) and the Toronto Extremity Salvage Score (TESS)).

Results. One patient died of systemic disease 2 years post-operatively and one patient had an axillary node recurrence resected 10 months post-operatively and remains free of disease 53 months later. The other 14 patients were alive with no evidence of disease at the time of the last follow-up. Complications after the osteochondral allografts (n=11) included two infections, four fractures and three subluxations in eight patients. Six of these patients required removal of the allograft; one had a repeat osteochondral allograft and five were converted to an arthrodesis. Complications after arthrodesis in the ten patients (five primary and five secondary arthrodeses) included two non-unions, one infection and one fracture in three patients. Patients who underwent shoulder arthrodesis scored better in all outcome measures and this was statistically significant in the MSTS 1993 (p=0.001, Mann–Whitney U Test).

Discussion. In this study, there was a trend towards improved function following arthrodesis compared to osteochondral allograft reconstruction following proximal humerus bone tumour resection.

The geometric osteotomy: joint preservation in juxta-articular surface bone neoplasms

Purpose. To present the oncologic and functional results of a consecutive series of patients treated by geometric osteotomy and allograft reconstruction for juxta-articular surface bone neoplasms.

Patients. Twelve consecutive patients (mean age 28 years) underwent excision of benign aggressive or malignant juxta-articular surface bone neoplasms. In each case, only part of the circumference of the bone was excised, and the joint surface was preserved and kept in continuity with the remainder of the bone. The defects were filled with allograft or autograff, and internally fixed as appropriate.

Methods. Patients were eligible for the study if they had a histologically proven, primary tumour of bone adjacent to a joint such that the turnout could be completely excised with a partial cortical resection and preservation of the joint. The database at the University Musculoskeletal Oncology Unit was used to identify all cases. Patient demographics and oncologic results were recorded. Functional assessment was performed using the Musculoskeletal Tumor Society rating scale and the Toronto Extremity Salvage Score.

Results. Nine tumours were about the knee and three were in the proximal humerus. Negative margins were achieved in all cases. No patient had metastatic disease at a mean follow-up of 56.5 months. There was one local recurrence and this was managed by conversion to a Van Nes rotationplasty. Functional results were excellent in the proximal humeral cases and in cases about the knee where the stabilizing ligaments were preserved. Cases with post-operative knee instability were less successful but none the less were well controlled with bracing.

Discussion. This technique offers an alternative to joint excision and prosthetic replacement in a group of young patients.

Functional outcomes after treatment of aggressive tumors in the distal radius

We aimed to determine whether wide excision and radiocarpal arthrodesis in patients with aggressive tumors of the distal radius resulted in more significant functional deficit than joint salvage procedures. We compared functional outcomes, surgical complications, and local tumor relapse in 33 consecutive patients. Fourteen patients initially had joint-sparing procedures, whereas 19 underwent wide resection and arthrodesis. At minimum final followup of 18 months (mean, 96 months; range, 18-204 months), local tumor relapse occurred in five of 14 patients after joint salvage versus zero of 19 after arthrodesis. Two of five patients with tumor recurrence retained their native joints, whereas three underwent resection and arthrodesis. Six of 19 patients had complications, including one nonunion, for which we performed additional surgery after arthrodesis. All patients remained disease-free at followup and none developed metastases. Disabilities of the Arm, Shoulder and Hand score, Toronto Extremity Salvage Score, and Musculoskeletal Tumor Society scores all indicated more disability after arthrodesis. Persistent pain, radiographic wrist arthritis, and weaker grip strength was seen in some patients following joint salvage. Whenever possible, joint preservation is preferable for the result of better extremity function, but weaker grip, higher local tumor relapse, and late arthritis remain concerns.

The influence of anatomic location on functional outcome in lower-extremity soft-tissue sarcoma

BACKGROUND

The purpose of this study was to explore the relationship between the anatomical location of lower-extremity soft-tissue sarcoma and functional outcome.

METHODS

Function was evaluated with the Musculoskeletal Tumor Society (MSTS 1993) score and Toronto Extremity Salvage Score (TESS); 207 patients (median age, 54 years) were eligible. The median maximum tumor diameter was 8.0 cm; 58 tumors were superficial and 149 were deep. Nine locations based on anatomical compartments were defined: 6 tumors were in the groin/femoral triangle; 8, the buttock; 52, the anterior thigh; 22, the medial thigh; 20, the posterior thigh; 10, the popliteal fossa; 13, the posterior calf; 11, the anterolateral leg; and 7, the foot or ankle.

RESULTS

Treatment of superficial tumors did not lead to significant changes in MSTS score (mean, 90.6% preoperatively vs. 93.0% postoperatively; P =.566) or TESS (mean, 86.4% preoperatively vs. 90.9% postoperatively; P =.059). Treatment of deep tumors lead to significant reductions in MSTS score and TESS (mean MSTS, 86.9% preoperatively vs. 83.0% postoperatively; P =.001; and mean TESS, 83.0% preoperatively vs. 79.4% postoperatively; P =.015). Anatomical location was not a significant predictor of aggregated MSTS and TESS evaluations. Exploratory analysis showed variation in MSTS pain and gait handicap or limp items and TESS dressing, sitting, bending, and bathing items by anatomical location.

CONCLUSIONS

The treatment of superficial tumors does not lead to significant changes in MSTS score or TESS. Anatomical location is not a significant predictor of aggregated MSTS and TESS evaluations. However, there is variation in MSTS and TESS item scores across anatomical locations.

Preoperative radiotherapy is effective in the treatment of fibromatosis

The use of preoperative radiation is well-established for soft tissue sarcoma, but its use in fibromatosis is not well-characterized. The purpose of this study was to examine the impact of preoperative radiotherapy on the local control of fibromatosis and to assess treatment-related morbidity in this setting. In particular we assessed complication rates in comparison with soft tissue sarcoma treatment. All patients with fibromatosis referred to this unit who received preoperative radiotherapy (50 Gy in 25 fractions) from 1988 to 2000 and who had at least 2 years of followup were included in this study. The rate of recurrence in this group was ascertained. Similarly constructed datasets from all patients with soft tissue sarcomas of the extremities who received preoperative radiation from 1986 to 1997 also were analyzed. The rates of complications in the two groups were compared. Fifty-eight patients were treated with preoperative radiation for fibromatosis and the median followup was 69 months. There were 11 local recurrences (19%). Major wound complications manifested in two patients (3.4%). Wound-related complications arose in 89 of 265 patients with soft tissue sarcomas (33.5%). There was a significant difference in the rate of major wound complications observed in the two groups. The use of radiotherapy before surgery is effective in the combined treatment of fibromatosis.

Function and health status outcomes in a randomized trial comparing preoperative and postoperative radiotherapy in extremity soft tissue sarcoma

PURPOSE

Morbidity associated with wound complications may translate into disability and quality-of-life disadvantages for patients treated with radiotherapy (RT) for soft tissue sarcoma (STS) of the extremities. Functional outcome and health status of extremity STS patients randomized in a phase III trial comparing preoperative versus postoperative RT is described.

PATIENTS AND METHODS

One hundred ninety patients with extremity STS were randomized after stratification by tumor size dichotomized at 10 cm. Function and quality of life were measured by the Musculoskeletal Tumor Society Rating Scale (MSTS), the Toronto Extremity Salvage Score (TESS), and the Short Form-36 (SF-36) at randomization, 6 weeks, and 3, 6, 12, and 24 months after surgery.

RESULTS

One hundred eighty-five patients had function data. Patients treated with postoperative RT had better function with higher MSTS (25.8 v 21.3, P <.01), TESS (69.8 v 60.6, P =.01), and SF-36 bodily pain (67.7 v 58.5, P =.03) scores at 6 weeks after surgery. There were no differences at later time points. Scores on the physical function, role-physical, and general health subscales of the SF-36 were significantly lower than Canadian normative data at all time points. After treatment arm was controlled for, MSTS change scores were predicted by a lower-extremity tumor, a large resection specimen, and motor nerve sacrifice; TESS change scores were predicted by lower-extremity tumor and prior incomplete excision. When wound complication was included in the model, patients with complications had lower MSTS and TESS scores in the first 2 years after treatment.

CONCLUSION

The timing of RT has minimal impact on the function of STS patients in the first year after surgery. Tumor characteristics and wound complications have a detrimental effect on patient function.

Pathologic fractures of the proximal femur secondary to benign bone tumors

Pathologic fractures of the proximal femur secondary to benign bone tumors often are difficult to treat because of specific anatomic features of this region and the aggressiveness of the tumors. Between 1986 and 1996, 11 patients presented with a pathologic fracture of the proximal femur secondary to a benign bone tumor. All were treated with a uniform approach consisting of biopsy, intralesional curettage, high-speed burring, and reconstruction using morselized allograft, autograft, and a fixed-angle implant. The average followup was 4 years 3 months (range, 24-114 months). One patient was lost to followup. All fractures healed, and there were no local recurrences and no cases of avascular necrosis. Functional evaluation revealed generally good results. Patients scored a mean of 32.6 on the original Musculoskeletal Tumor Society scale and 95.8 on the revised version. The average Toronto Extremity Salvage Score was 91.3. With the numbers available, there were no significant differences between the study group and population norms in the Short Form-36. These results suggest that a uniform approach based on preservation of the femoral head can be applied successfully to the treatment of these lesions with good local tumor control, fracture healing, and acceptable functional outcomes.

Classification of positive margins after resection of soft-tissue sarcoma of the limb predicts the risk of local recurrence

We considered whether a positive margin occurring after resection of a soft-tissue sarcoma of a limb would affect the incidence of local recurrence. Patients with low-grade liposarcomas were expected to be a low-risk group as were those who had positive margins planned before surgery to preserve critical structures. Two groups, however, were expected to be at a higher risk, namely, patients who had undergone unplanned excision elsewhere with a positive margin on re-excision and those with unplanned positive margins occurring during primary resection. Of 566 patients in a prospective database, 87 with positive margins after limb-sparing surgery and adjuvant radiotherapy were grouped according to the clinical scenario by an observer blinded to the outcome. The rate of local recurrence differed significantly between the two low- (4.2% and 3.6%) and the two high-risk groups (31.6% and 37.5%). This classification therefore provides useful information about the incidence of local recurrence after positive-margin resection.

Periosteal chondroid tumors: radiologic evaluation with pathologic correlation

OBJECTIVE

The purpose of this study was to determine whether the imaging features of periosteal chondroid tumors correlate with histopathology.

MATERIALS AND METHODS

Twenty-two patients (nine women and 13 men; mean age, 33 years) with pathologically proven periosteal chondroid lesions were retrospectively reviewed. The imaging modalities included conventional radiography (n = 17), CT (n = 10), and MR imaging (n = 14). The images were reviewed by two osteoradiologists, with agreement by consensus. Evaluation criteria included lesion location, mineralization, and size; periosteal reaction; and cortical response. Intramedullary extension, adjacent intramedullary edema, soft-tissue edema, and intrinsic characteristics were also evaluated on MR imaging. After the evaluation, a radiologic diagnosis of chondroma or chondrosarcoma was obtained. An experienced osteopathologist who was unaware of the patient's medical history and radiologic findings reviewed all histopathology. Agreement between the radiologic and the histopathologic diagnosis was tested using the kappa analysis. Imaging features were correlated with the pathologic findings, and a statistical analysis was performed.

RESULTS

Using strict pathologic criteria, we diagnosed 11 chondromas and 11 chondrosarcomas (nine, grade I; two, grade II). Moderate agreement was reached between the radiologic and the pathologic diagnosis (kappa = 0.55). The size of periosteal chondrosarcomas (range, 3-14 cm; median, 4 cm) was considerably larger than the size of the chondromas (range, 1-6.5 cm; median, 2.5 cm; p < 0.05). Other imaging features did not significantly correlate with benign versus malignant disease at pathology (all p > 0.05).

CONCLUSION

A variable overlap existed in the imaging appearances of benign and malignant periosteal chondroid lesions, with size being the most reliable indicator in distinguishing the two lesions. This and the fact that histologic differentiation of the entities can be difficult, suggests that surgical wide excision may be the most appropriate procedure in treating patients with lesions greater than 3 cm.

Classification of positive margins after resection of soft-tissue sarcoma of the limb predicts the risk of local recurrence

We considered whether a positive margin occurring after resection of a soft-tissue sarcoma of a limb would affect the incidence of local recurrence. Patients with low-grade liposarcomas were expected to be a low-risk group as were those who had positive margins planned before surgery to preserve critical structures. Two groups, however, were expected to be at a higher risk, namely, patients who had undergone unplanned excision elsewhere with a positive margin on re-excision and those with unplanned positive margins occurring during primary resection.

Of 566 patients in a prospective database, 87 with positive margins after limb-sparing surgery and adjuvant radiotherapy were grouped according to the clinical scenario by an observer blinded to the outcome. The rate of local recurrence differed significantly between the two low- (4.2% and 3.6%) and the two high-risk groups (31.6% and 37.5%). This classification therefore provides useful information about the incidence of local recurrence after positive-margin resection.

Comparison of p53 mutations in patients with localized osteosarcoma and metastatic osteosarcoma

BACKGROUND

In some malignancies, p53 mutations are associated with tumor progression. To address the role of p53 mutations in the development and progression of osteosarcoma, the authors analyzed specimens from 247 patients with primary localized osteosarcomas and 25 patients with osteosarcomas that were metastatic at the time of diagnosis. The group included 27 matched biopsy-resection specimens and 21 biopsy-metastasis paired specimens.

METHODS

The authors examined the nature and location of p53 mutations (exons 4-10) by polymerase chain reaction-single-strand conformation polymorphism and confirmed mutations by direct DNA sequencing.

RESULTS

The overall frequency of p53 mutations was 22% (60 of 272 specimens), with 13 of 60 mutations located in exons 4 or 10. A similar proportion of localized osteosarcomas had alterations of the p53 gene (55 of 247 specimens; 22.3%) compared with tumors from patients who had metastases at the time of diagnosis (5 of 25 specimens; 20%; P = 0.96). Patients who had p53 missense mutations were older compared with patients who had nonsense alterations or a wild type gene (P = 0.01). Examination of paired biopsy-resection and biopsy-metastasis specimens revealed that the p53 status was concordant between the biopsy and later tumor specimens in all patients.

CONCLUSIONS

The p53 mutation status did not differentiate between patients who presented with a localized osteosarcoma and those who presented with metastases at the time of diagnosis. The current data indicate that p53 mutations are not late events in osteosarcoma tumor progression, because they are evident before the development of metastases. The inclusion of exons 4 and 10 increased the sensitivity of the analysis.

Extraskeletal Ewing sarcoma in a 77-year-old woman

Extraskeletal Ewing sarcoma (EES) is a rare soft tissue tumor that is morphologically indistinguishable from Ewing sarcoma of bone. It is usually found in young people, but several cases have occurred in patients older than 50 years. The differential diagnoses include other small, blue round cell tumors (SBRCTs) and other members of the Ewing family of tumors such as the primitive neuroectodermal tumor. We present a case of EES in the left inguinal region of a 77-year-old woman. The tumor was distinguished from other SBRCTs by lack of immunoreactivity for epithelial, lymphoid, vascular, neuroendocrine, neural, histiocytic, and muscle markers. Primitive neuroectodermal tumor was excluded because of the lack of neural differentiation by histologic analysis, immunohistochemistry, and electron microscopy. Extraskeletal Ewing sarcoma was confirmed by characteristic features on histologic analysis, histochemistry, immunohistochemistry, and electron microscopy and by the presence of the t(11;22)(q24;q12) fusion transcript detected by reverse transcriptase-polymerase chain reaction. This case serves to remind the reader that EES is not a tumor that occurs exclusively in young patients.

Instability after major tumor resection: prevention and treatment

Instability is a significant problem after resection of musculoskeletal tumors. In this article, the authors discuss the issue of instability after resections of the pelvis, the femur, and the proximal tibia. The options for reconstruction in each area are discussed along with a review of the literature and a description of the authors' preferred approach.

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.

Comparison of two methods of reconstruction for primary malignant tumors at the knee: a sequential cohort study

BACKGROUND AND OBJECTIVES

The purpose of this study was to compare the complications and functional outcome associated with the use of an irradiated allograft-implant composite or a bone-ingrowth modular tumor prosthesis for replacement of the knee joint after resection of a bone sarcoma from the distal femur or proximal tibia.

METHODS

Eleven patients initially received an allograft reconstruction, followed by 64 treated with a tumor prosthesis. The primary analysis concerned reconstructive failure, defined by the requirement for removal of the original construct. Functional outcome was assessed by using the 1987 Musculoskeletal Tumor Society rating system.

RESULTS

Reconstructive failure occurred in 6 of 11 (55%) allograft constructs compared with 10 of 64 (16%) tumor prostheses (P = 0.009). Failures were due to infection (2 of 11 allografts versus 4 of 64 prostheses; P = 0.2) or mechanical complications (4 of 11 allograft fractures versus 5 of 64 broken prosthetic stems and 1 aseptically loose prosthesis; P = 0.03). The limb salvage rate was 95% (61 of 64) for patients with a tumor prosthesis compared with 64% (7 of 11) for those with an allograft (P = 0.007). Patients with a tumor prosthesis had a better functional outcome with a mean score of 75% compared with 57% for those with an allograft reconstruction (P = 0.006).

CONCLUSIONS

This comparative study suggests that limb salvage surgery at the knee has a better and more predictable outcome with a tumor prosthesis than with an allograft-implant reconstruction.

p53 missense but not truncation mutations are associated with low levels of p21(CIP1/WAF1) mRNA expression in primary human sarcomas

Many growth-suppressing signals converge to control the levels of the CDK inhibitor p21(CIP1/WAF1). Some human cancers exhibit low levels of expression of p21(CIP1/WAF1) and mutations in p53 have been implicated in this down-regulation. To evaluate whether the presence of p53 mutations was related to the in vivo expression of p21(CIP1/WAF1) mRNA in sarcomas we measured the p21(CIP1/WAF1) mRNA levels for a group of 71 primary bone and soft tissue tumours with known p53 status. As expected, most tumours with p53 mutations expressed low levels of p21(CIP1/WAF1)mRNA. However, we identified a group of tumours with p53 gene mutations that exhibited normal or higher levels of p21(CIP1/WAF1) mRNA. The p53 mutations in the latter group were not the common missense mutations in exons 4-9, but were predominantly nonsense mutations predicted to result in truncation of the p53 protein. The results of this study suggest that different types of p53 mutations can have different effects on the expression of downstream genes such as p21(CIP1/WAF1) in human sarcomas.

Soft tissue sarcomas involving the pelvis

BACKGROUND AND OBJECTIVES

Soft tissue sarcomas (STS) of the true pelvis are rare tumors and there is little information in the literature related to pelvic STS. The purposes of this review were to understand the anatomic extension of these tumors to better plan surgical treatment and to determine the outcome of these patients.

METHODS

Eighteen consecutive patients presenting between 1987 and 1995 with soft tissue sarcomas involving the true pelvis were retrospectively reviewed at minimum follow-up of 18 months. Cross-sectional imaging was reviewed for each patient to determine the anatomical location of the lesions.

RESULTS

The tumors were confined to the true pelvis in 4 patients, extended to the retroperitoneum in three cases, and extended to the thigh in 11 patients. Adjuvant radiation was administered to all but 2 patients who had received radiation to the region in the past and all patients underwent surgical resection (local resection in 13 patients and hindquarter amputation in 5 patients). Surgical resection had a high rate of morbidity and complications including positive resection margins in nine individuals. Of the 18 patients, 11 died at a mean time of 15.5 (2-58) months from surgery, 4 were alive with evidence of disease at a mean time of 44.3 (18-68) months, and 3 were alive with no evidence of disease at a mean time of 57 (43-71) months.

CONCLUSIONS

Soft tissue sarcoma of the pelvis is fortunately a rare disease with a high risk of local and systemic disease progression despite treatment with irradiation and surgical resection.

Changing rates of cancer. The hazards of using a single definition

Changing cancer rates, abstracted from tumor registries, are used to make inferences about the effect of carcinogens and cancer treatments on a population-wide basis. We compared the annual age-standardized incidence rates of extremity soft tissue sarcomas from two large tumor registries using different case definitions. We identified all limb soft tissue sarcoma cases diagnosed 1973-1993 in the Ontario Cancer Registry (OCR) and the Surveillance, Epidemiology, and End Results (SEER) databases. Two case definitions for limb soft tissue sarcoma were used based on missing data, incomplete diagnostic methods and ICD-9 codes; an upper limit estimate of the rates which included all possible cases of limb soft tissue sarcoma and a lower limit estimate of the rates which included all definite cases of limb soft tissue sarcoma (with the true rates lying in between). The upper limit OCR rates showed a statistically significant decreasing linear trend (slope = -0.021, P < 0.01). Whereas the slope of the OCR lower limit regression line showed a statistically significant increase in rates (slope = 0.01, P = 0.04). Neither the upper or lower limit SEER rates had a statistically significant linear trend (slope = 0.002, P = 0.60 and slope = 0.001, P = 0.18, respectively). Case definition affects incidence rates and changing rates of cancer. Thus the use of a single case definition along with changing coding practices may alone explain changing cancer rates.

Sciatic nerve resection in the thigh: a functional evaluation

Patients with a soft tissue malignancy involving the sciatic nerve who present with neurologic loss generally are advised to have an amputation. Twenty patients who underwent limb-sparing procedures with complete resection of the sciatic nerve as treatment for neurofibrosarcomas (12 patients), liposarcomas (four patients), malignant fibrous histiocytomas (two patients), recurrent desmoid tumor (one patient), and epithelioid hemangioendothelioma (one patient) were reviewed retrospectively. The mean age of these nine women and 11 men at the time of surgery was 51 years (range, 28-84 years). The right sciatic nerve was affected in 12 patients. These tumors were large and high grade. A mean of 22 cm of the nerve had to be resected (range, 8-42 cm). Ten patients received preoperative radiotherapy and 16 patients had intraoperative or postoperative radiotherapy. At a mean followup of 35 months (range, 7-97 months), 14 of the 20 patients were alive. Two patients had local recurrences develop (10%), whereas 12 patients had distant metastases. The function of the 10 patients as assessed by the Toronto Extremity Salvage Score averaged 74%. Most patients indicated that walking in the house is not difficult, but walking is compromised as soon as an effort is needed. Four patients walk without a cane, four needed one cane, and two needed two canes. The patients experienced stiffness, a sense of numbness, and premature fatigue. The use of analgesics was infrequent. Generally, patients rated themselves to be mildly to moderately disabled. From this small number of patients, it is shown that a tumor involving the sciatic nerve can be treated by limb-sparing surgery, including complete nerve resection, as an alternative to hip disarticulation or hindquarter amputation because the limb salvage option provides an acceptable functional outcome.

MDR1 gene expression and outcome in osteosarcoma: a prospective, multicenter study

PURPOSE

Increased expression of the multidrug resistance gene (MDR1) has been implicated in osteosarcoma prognosis. This study represents the first prospective assessment of the prognostic value of MDR1 mRNA expression in patients with newly diagnosed extremity osteosarcoma.

PATIENTS AND METHODS

A series of patients with high-grade, nonmetastatic extremity osteosarcoma were enrolled from six tertiary care institutions and observed prospectively for tumor recurrence (median follow-up duration, 30 months). All patients were treated with (neo)adjuvant chemotherapy and surgery. Tumors from 123 patients were analyzed for MDR1 mRNA expression. The association of the level of MDR1 expression with the risk of systemic recurrence was examined using survival analyses with traditional and histologic markers as prognostic factors.

RESULTS

Using the highest MDR1 value for each patient, a dose-response relationship was not identified between the level of MDR1 expression and systemic relapse (relative risk, 1.15; P =.44). Analyses based on biopsy or resection values alone gave similar results (P =.11 and.41, respectively, log rank test). In multivariate analysis, large tumor size (> 9 cm) was the only significant independent predictor of systemic outcome (relative risk, 2.8; P =.002).

CONCLUSION

We did not identify any correlation between MDR1 mRNA expression and disease progression in patients with osteosarcoma. It is likely that alterations in other genes are involved in resistance to chemotherapy in osteosarcoma and that they play a more critical role than MDR1 in this disease.

Predictors of functional outcomes following limb salvage surgery for lower-extremity soft tissue sarcoma

BACKGROUND AND OBJECTIVES

Patient function has been conceptualized by clinical measures such as joint motion, muscle strength, disability, and general health status. The purpose of the current study was to evaluate tumor and treatment variables predictive of these conceptually different posttreatment functional outcomes in patients treated with limb preservation surgery for lower-extremity soft tissue sarcoma.

METHODS

One hundred seventy-two patients with minimum 1-year follow-up were evaluated using the following outcomes: impairment, measured by the 1987 and 1993 versions of the Musculoskeletal Tumor Society Rating Scale (MSTS); disability, measured by the Toronto Extremity Salvage Score (TESS); and general health status, using the Short Form-36 (SF-36). Tumor and treatment-related variables (age, gender, presenting disease status, anatomic site, tumor size, grade, depth, prior excision, irradiation, bone resection, motor nerve sacrifice, and complications) were extracted from the STS database.

RESULTS

Large tumor size, bone resection, motor nerve resection, and complications were predictive of lower MSTS 1987 and 1993 scores. Patients with large, high-grade tumors who required motor nerve resection were more disabled, as reflected by lower TESS scores. Only age and prior surgery were adverse predictors of SF-36 score.

CONCLUSIONS

These results demonstrate that different factors are predictive of different patient outcomes, specifically, impairment, disability, and general health status. It is important to define function when counseling patients regarding their potential recovery based on tumor and treatment-related variables. J. Surg. Oncol. 2000;73:206-211.

Multidrug resistance-1 gene expression does not increase during tumor progression in the MGH-OGS murine osteosarcoma tumor model

In addition to its possible role in drug resistance, expression of the multidrug resistance-1 gene may also be associated with a more malignant phenotype and tumor progression. This study evaluated its expression during tumor progression in the MGH-OGS transplantable murine osteosarcoma tumor model. Three variables of tumor progression were analyzed: tumor size, local recurrence, and metastasis. With a highly sensitive reverse transcription-polymerase chain reaction method, mRNA levels of multidrug resistance-1 were compared in primary tumors of different sizes. In addition, the levels were compared in primary, locally recurrent, and metastatic tumors isolated from individual mice. No significant difference was found in the levels of expression with increasing primary tumor size. In addition, the levels in primary, locally recurrent, and metastatic tumors were not significantly different. Our results indicate that--at least in the MGH-OGS tumor model, which is analogous to the majority of spontaneously occurring human osteosarcomas in that it has low levels of multidrug resistance-1/P-glycoprotein and is sensitive to doxorubicin--there is no evidence of upregulation of multidrug resistance-1 expression during tumor progression.

Predictors of functional outcomes following limb salvage surgery for lower-extremity soft tissue sarcoma

BACKGROUND AND OBJECTIVES

Patient function has been conceptualized by clinical measures such as joint motion, muscle strength, disability, and general health status. The purpose of the current study was to evaluate tumor and treatment variables predictive of these conceptually different posttreatment functional outcomes in patients treated with limb preservation surgery for lower-extremity soft tissue sarcoma.

METHODS

One hundred seventy-two patients with minimum 1-year follow-up were evaluated using the following outcomes: impairment, measured by the 1987 and 1993 versions of the Musculoskeletal Tumor Society Rating Scale (MSTS); disability, measured by the Toronto Extremity Salvage Score (TESS); and general health status, using the Short Form-36 (SF-36). Tumor and treatment-related variables (age, gender, presenting disease status, anatomic site, tumor size, grade, depth, prior excision, irradiation, bone resection, motor nerve sacrifice, and complications) were extracted from the STS database.

RESULTS

Large tumor size, bone resection, motor nerve resection, and complications were predictive of lower MSTS 1987 and 1993 scores. Patients with large, high-grade tumors who required motor nerve resection were more disabled, as reflected by lower TESS scores. Only age and prior surgery were adverse predictors of SF-36 score.

CONCLUSIONS

These results demonstrate that different factors are predictive of different patient outcomes, specifically, impairment, disability, and general health status. It is important to define function when counseling patients regarding their potential recovery based on tumor and treatment-related variables. J. Surg. Oncol. 2000;73:206-211.

Periprosthetic bone remodelling around a prosthesis for distal femoral tumours

We used dual-energy x-ray absorptiometry (DEXA) to evaluate the extent of periprosthetic bone remodelling around a prosthesis for distal femoral reconstruction, the Kotz modular femoral tibial replacement (KMFTR; Howmedica, Rutherford, New Jersey). A total of 23 patients was entered into the study which had four parts: 1) 17 patients were scanned three times on both the implant and contralateral legs to determine whether the precision of DEXA measurements was adequate to estimate bone loss surrounding the anchorage piece of the KMFTR; 2) in 23 patients the bone mineral density (BMD) in different regions of interest surrounding the diaphyseal anchorage was compared with that of the contralateral femur at the same location to test whether there was consistent evidence of loss of BMD adjacent to the prosthetic stem; 3) in 12 patients sequential studies were performed about one year apart to compare bone loss; and 4) bone loss was compared in ten patients with implants fixed by three screws and in 13 without screws.

The mean coefficients of variation (SD/mean) for the 17 sets of repeated scans ranged from 2.9% to 7.8% at different regions of interest in the KMFTR leg and from 1.4% to 2.5% in the contralateral leg. BMD was decreased in the KMFTR leg relative to the contralateral limb and the percentage of BMD loss in general increased as the region of interest moved distally in the femur. Studies done after one year showed no consistent pattern of progressive bone loss between the two measurements. The ten patients with implants fixed by screws were found to have a mean loss of BMD of 42% in the most distal part of the femur, while the 13 without screw fixation had a mean loss of 11%.

DEXA was shown to have adequate precision to evaluate loss of BMD around the KMFTR. This was evident relative to the contralateral leg in all patients and generally increased in the most distal part of the femur. In general, it stabilised between two measurements taken one year apart and was greater surrounding implants fixed by cross-locking screws.

Periprosthetic bone remodelling around a prosthesis for distal femoral tumours. Measurement by dual-energy X-ray absorptiometry (DEXA)

We used dual-energy x-ray absorptiometry (DEXA) to evaluate the extent of periprosthetic bone remodelling around a prosthesis for distal femoral reconstruction, the Kotz modular femoral tibial replacement (KMFTR; Howmedica, Rutherford, New Jersey). A total of 23 patients was entered into the study which had four parts: 1) 17 patients were scanned three times on both the implant and contralateral legs to determine whether the precision of DEXA measurements was adequate to estimate bone loss surrounding the anchorage piece of the KMFTR; 2) in 23 patients the bone mineral density (BMD) in different regions of interest surrounding the diaphyseal anchorage was compared with that of the contralateral femur at the same location to test whether there was consistent evidence of loss of BMD adjacent to the prosthetic stem; 3) in 12 patients sequential studies were performed about one year apart to compare bone loss; and 4) bone loss was compared in ten patients with implants fixed by three screws and in 13 without screws. The mean coefficients of variation (SD/mean) for the 17 sets of repeated scans ranged from 2.9% to 7.8% at different regions of interest in the KMFTR leg and from 1.4% to 2.5% in the contralateral leg. BMD was decreased in the KMFTR leg relative to the contralateral limb and the percentage of BMD loss in general increased as the region of interest moved distally in the femur. Studies done after one year showed no consistent pattern of progressive bone loss between the two measurements. The ten patients with implants fixed by screws were found to have a mean loss of BMD of 42% in the most distal part of the femur, while the 13 without screw fixation had a mean loss of 11%. DEXA was shown to have adequate precision to evaluate loss of BMD around the KMFTR. This was evident relative to the contralateral leg in all patients and generally increased in the most distal part of the femur. In general, it stabilised between two measurements taken one year apart and was greater surrounding implants fixed by cross-locking screws.

Comparison between a 2- and 3-grade system in predicting metastatic-free survival in extremity soft-tissue sarcoma

BACKGROUND AND OBJECTIVES

The purpose of this study was to determine whether a histologic grading system consisting of 2 or 3 categories had better discrimination for predicting metastasis-free survival in extremity soft-tissue sarcoma.

METHODS

One hundred thirty patients with nonmetastatic soft-tissue sarcoma were identified and the histologic grade (3-grade system) for each tumor was determined. For the 2-grade system, grade was determined by collapsing 3 grades into 2. The Kaplan-Meier method was used to estimate disease free survival.

RESULTS

By use of a 3-grade system, grade 2 tumors showed a 5.2-fold and grade 3 tumors a 9-fold increased risk of systemic relapse when compared with grade 1 tumors. When grade 2 and 3 tumors were combined, they had a 2.6-fold increased risk of systemic relapse compared with grade 1 tumors. When grade 1 and 2 tumors were combined, grade 3 tumors had an 8.4-fold risk of relapse. After data were controlled for size and depth of tumor, each increase in grade in the 3-grade system showed a successive 2.3-fold increase in risk of systemic relapse.

CONCLUSIONS

A 3-grade system may be more appropriate for predicting systemic relapse than 2 grades. A prospective study is required to confirm this.

Expression of osteocalcin and its transcriptional regulators core-binding factor alpha 1 and MSX2 in osteoid-forming tumours

Osteosarcoma, fibrous dysplasia, and myositis ossificans contain osteoid-producing cells that are not necessarily morphologically typical osteoblasts. Nevertheless, these pathologic cells may share differentiation steps with osteoblasts at the molecular level. Osteocalcin, a bone-specific extracellular matrix protein, is a marker of mature osteoblasts. Osteocalcin is upregulated by the transcription factor core-binding factor alpha 1, which is responsible for commitment to the osteoblastic lineage, and is downregulated by MSX2, a homeobox-containing transcription factor expressed during the early proliferative phase of osteoblast differentiation. Semiquantitative reverse transcription-polymerase chain reaction was used to compare expression levels of osteocalcin, core-binding factor alpha 1, and MSX2 in 34 osteosarcoma, five fibrous dysplasia, and five myositis ossificans specimens, as well as in seven normal cortical bone samples. Despite normal or elevated levels of core-binding factor alpha-1 expression in most specimens, osteocalcin expression was low or undetectable in most cases of osteosarcoma (25 of 34) and myositis ossificans (4 of 5). Single-strand conformation polymorphism and sequencing did not identify any mutations in the DNA-binding domain of core-binding factor alpha 1. However, a high level of MSX2 expression was demonstrated in these lesions, which may inhibit osteocalcin transcription. The presence of moderate levels of osteocalcin in fibrous dysplasia may contribute to the characteristic disconnected appearance of trabeculae in that entity because osteocalcin is a negative regulator of bone formation.

Intradermal injection of autologous dermal fibroblasts improves wound healing in irradiated skin

BACKGROUND

Despite its well-recognized benefits in the management of several solid tumors, the use of radiotherapy prior to surgery is associated with a high incidence of significant surgical wound healing complications. Radiation-induced damage to dermal fibroblasts has been proposed as an important cause. We hypothesized that the introduction of normal, unirradiated fibroblasts into previously irradiated skin would enhance healing of the subsequent surgical wound.

MATERIALS AND METHODS

Four groups of wounds were examined in female Wistar rats: (1) unirradiated skin (n = 10), (2) irradiated skin injected with tissue culture medium alone (n = 17), (3) irradiated skin injected with autologous dermal fibroblasts (n = 17), and (4) irradiated skin injected with irradiated autologous dermal fibroblasts (n = 7). Wounds were evaluated biomechanically and histologically.

RESULTS

The biomechanical values of breaking load, ultimate tensile strength, elastic modulus, and toughness were significantly greater in the irradiated wounds injected with fibroblasts than those injected with medium only. These cell-injected wounds did not perform as well biomechanically as those in unirradiated skin. Irradiating the cells prior to injection resulted in biomechanical results no better than those in medium-injected wounds.

CONCLUSIONS

These results demonstrate that injection of normal, unirradiated fibroblasts significantly improves healing of the irradiated surgical wound. These cells are likely better able to respond to the proliferative, migratory, and synthetic demands of the wound healing environment, as injection of irradiated cells has an equivalent effect on healing as injection of medium alone.

Molecular alterations in bone and soft-tissue sarcoma

Understanding the molecular alterations evident in human cancer offers the potential for more meaningful diagnosis and more accurate prediction of cancer risk as well as the hope of developing novel therapies. In this review, several of the molecular abnormalities identified in both bone and soft-tissue sarcoma are outlined. Some sarcomas exhibit consistent gene translocations, which produce a unique oncoprotein that can serve as a molecular fingerprint for the sarcoma subtype. Mutations in tumour suppressor genes result in cell proliferation that is not regulated by normal cell cycle control genes. Amplification (multiple copies) of genes that act as positive controls on cell division have a similar effect on increasing cell proliferation. Finally, the understanding of drug resistance and sarcoma response to signalling systems such as IGF ligand and receptors may help in designing new therapies based on molecular changes in the cancer.

Treatment of giant-cell tumors of long bones with curettage and bone-grafting

BACKGROUND

The use of curettage, phenol, and cement is accepted by most experts as the best treatment for giant-cell tumor of bone. The present study was performed to evaluate whether equivalent results could be obtained with curettage with use of a high-speed burr and reconstruction of the resulting defect with autogenous bone graft with or without allograft bone.

METHODS

The prospectively collected records of patients who had a giant-cell tumor of a long bone were reviewed to determine the rate of local recurrence after treatment with curettage with use of a high-speed burr and reconstruction with autogenous bone graft with or without allograft bone. All of the patients were followed clinically and radiographically, and a biopsy was performed if there were any suspicious changes.

RESULTS

Fifty-nine patients met the criteria for inclusion in the study. According to the grading system of Campanacci et al., two patients (3 percent) had a grade-I tumor, twenty-nine (49 percent) had a grade-II tumor, and twenty-eight (47 percent) had a grade-III tumor. Seventeen patients (29 percent) had a pathological fracture at the time of presentation. The mean duration of follow-up was eighty months (range, twenty-eight to 132 months). Seven patients (12 percent) had a local recurrence. Six of these seven were disease-free at the latest follow-up examination after at least one additional treatment with curettage or soft-tissue resection (one patient). One patient had resection and reconstruction with a prosthesis after a massive local recurrence and pulmonary metastases.

CONCLUSIONS

Despite the high rates of recurrence reported in the literature after treatment of giant-cell tumor with curettage and bone-grafting, the results of the present study suggest that the risk of local recurrence after curettage with a high-speed burr and reconstruction with autogenous graft with or without allograft bone is similar to that observed after use of cement and other adjuvant treatment. It is likely that the adequacy of the removal of the tumor rather than the use of adjuvant modalities is what determines the risk of recurrence.

Functional outcome in amputation versus limb sparing of patients with lower extremity sarcoma: a matched case-control study

OBJECTIVE

To quantify the differences in physical disability and handicap experienced by patients with lower extremity sarcoma who required amputation for their primary tumor as compared with those treated by limb-sparing surgery.

DESIGN

Matched case-control study. Twelve patients with amputation were matched with 24 patients treated by limb-sparing surgery on the following variables: age, gender, length of follow-up, bone versus soft-tissue tumor, anatomic site, and treatment with adjuvant chemotherapy.

PATIENTS

Patients who underwent above-knee amputation (AKA) or below-knee amputation (BKA) for primary soft-tissue or bone sarcoma, who had not developed local or systemic recurrence, and who had been followed up for at least 1 year since surgery.

MAIN OUTCOME MEASURES

The Toronto Extremity Salvage Score (TESS), a measure of physical disability; the Shortform-36 (SF-36), a generic health status measure; and the Reintegration to Normal Living (RNL), a measure of handicap.

RESULTS

Mean TESS score for the patients with amputations was 74.5 versus 85.1 for the limb-sparing patients. (p = .15). Only the physical function subscale of the SF-36 showed statistically significant differences, with means of 45 and 71.1 for the amputation versus limb-sparing groups, respectively (p = .03). The RNL for the amputation group was 84.4 versus 97 for the limb-sparing group (p = .05). Seven of the 12 patients with amputations experienced ongoing difficulty with the soft tissues overlying their stumps.

CONCLUSIONS

There was a trend toward increased disability for those in the amputation group versus those in the limb-sparing group, with the amputation group showing significantly higher levels of handicap. These data suggest that the differences in disability between amputation and limb-sparing patients are smaller than anticipated. The differences may be more notable in measuring handicap.

Gender issues in patients with extremity soft-tissue sarcoma: a pilot study

Soft-tissue sarcoma (STS) affects men and women with equal frequency and commonly presents as an asymptomatic mass in patients 40 to 50 years of age. Recent study has identified physical, emotional, and psychological factors associated with a diagnosis of malignancy, but the tissues affecting the STS patient population may differ from those of more common cancers due to physical disability secondary to treatment. Research to date has not dealt specifically with gender differences in the reaction and adaptation to the cancer diagnosis. This pilot study was designed to evaluate the treatment experiences of five males and five females treated with surgery and radiation for STS of the thigh and followed posttreatment for at least 2 years. The open-ended interview was used to collect data, which was then subjected to a constant comparative analysis technique. The STS patients shared many concerns of cancer patients, with additional physical complaints. Physical symptoms were common to men and women, but women adapted more easily with explanation. Women feared losing life, family role, and relationships. Along with men, they also feared the losses of limb and career. For women, support included faith and sharing stories with others, whereas men preferred to deal with their illnesses individually and concealed emotions from loved ones. The perception of disease time frame was also distinct, with men adopting a fatalistic attitude and regarding their disease as an isolated episode. Women believed their condition was ongoing. Women need repeated information from several sources along with reassurance and increased social support, whereas men prefer the minimum of social support, requiring instead independence and extra attention to physical limitations. These results can improve STS patient treatment by increasing awareness in the patient, family, and medical team of the psychosocial issues that can be expected to arise.

Evaluation of the allograft-prosthesis composite technique for proximal femoral reconstruction after resection of a primary bone tumour

OBJECTIVE

To evaluate clinical and functional outcomes resulting from the allograft-composite technique used for proximal femoral osteoarticular reconstruction in patients who had limb salvage surgery for primary bone tumours.

DESIGN

A retrospective review of a prospectively gathered database to provide a descriptive study.

SETTING

A tertiary care musculoskeletal oncology unit in a university hospital.

PATIENTS AND INTERVENTIONS

Patients treated between 1987 and 1993 were eligible for inclusion in this study if they met the following criteria: they were treated surgically for a primary malignant bone tumour; and a proximal femoral allograft-implant composite technique was used for the reconstruction.

MAIN OUTCOME MEASURES

Major postoperative complications with emphasis on mechanical complications in the reconstructive composite implant. Functional outcome in a subset of patients using the 1987 and 1994 versions of the Musculoskeletal Tumor Society instrument, the Short-Form-36 and the Toronto Extremity Salvage Score.

RESULTS

There were 5 mechanical and 2 infectious complications requiring surgical intervention. Functional scores were generally low.

CONCLUSIONS

Our results suggest that the perceived benefits of the composite technique may accrue only to a few patients, partly owing to the risk of mechanical complications. Although these can be reduced by avoiding the use of cement in the host femur, the generally poor functional outcomes suggest that this technique needs to be studied further in this group of patients and compared with other reconstructive techniques, particularly the prosthetic implant.

Co-amplification and overexpression of CDK4, SAS and MDM2 occurs frequently in human parosteal osteosarcomas

Amplification of genes in the 12q13-15 region occurs frequently in several malignancies including osteosarcoma. The products of these amplified genes are thought to provide cancer cells with a selective growth advantage; however, the specific gene(s) driving this amplicon is unknown. We have previously shown that the SAS gene is amplified in most parosteal osteosarcomas. In this study we analysed additional putative growth regulatory genes in this chromosomal region in 24 primary osteosarcoma specimens. CDK4 and SAS were coamplified in 6/6 parosteal tumors, and MDM2 was also amplified in 4/5 parosteal cases. In comparison, amplification occurred in only 2/16 classical intramedullary osteosarcomas and involved the SAS gene. Each amplified gene had a correspondingly elevated mRNA level. Four high grade intramedullary tumors had elevated mRNA expression of SAS, but did not exhibit gene amplification. Gene amplification/overexpression was not associated with metastatic disease and did not change markedly with tumor progression, as evidenced by analysis of sequential tumor specimens from eight patients. Three other genes in the 12q13-15 region (CDK2, WNT1 and WNT10b) were not amplified in any of the tumors. The different patterns of gene amplification and overexpression of CDK4, SAS and MDM2 in parosteal and intramedullary osteosarcomas may help explain the disparity in the biological behaviour of these two types of osteosarcoma.

Capsular replacement with synthetic mesh: effectiveness in preventing postoperative dislocation after wide resection of proximal femoral tumors and prosthetic reconstruction

We describe a surgical technique for replacing the hip joint capsule using synthetic mesh after oncological resections of the proximal femur that resulted in gross intraoperative instability of the prosthetic reconstruction. The results of its use in 13 patients, 6 of whom also had pelvic resections, are described. These patients were selected from a total group of 88 patients undergoing proximal femoral replacement, 75 of whom did not require capsular replacement (none of these 75 patients have experienced dislocation). In the group requiring capsular reconstruction, 1 of 4 patients with bipolar hemiarthroplasty and 4 of 9 patients with total hip replacements experienced dislocation after operation. Of the dislocated total hip replacements, 1 remains chronically dislocated, and 3 were successfully stabilized by open reduction with further capsular augmentation. Given that the resections involved removal of most of the soft tissues stabilizing the hip joint, we believe that the technique of capsular reconstruction is useful in this difficult group of patients.

Expression of insulin-like growth factor receptor, IGF-1, and IGF-2 in primary and metastatic osteosarcoma

BACKGROUND AND OBJECTIVES

We have previously shown that insulin-like growth factor (IGF)-responsive murine sarcomas demonstrate inhibition of local and metastatic disease growth when implanted in an IGF-deficient host animal. In this experiment, we tested whether IGF receptor (IGF-R) and ligands were expressed in human primary and metastatic osteosarcomas.

METHODS

Fifty-two specimens of human osteosarcoma tumor from 48 patients were assayed for IGF-R, IGF-1, and IGF-2 using reverse transcriptase polymerase chain reaction.

RESULTS

Twenty-one of 46 tumors analyzed had levels of expression of IGF-R greater than or equal to the positive control cell line. Twenty-seven of 44 expressed levels of IGF-1 greater than or equal to the positive control, as did 21 of 38 cases assayed for IGF-2. No differences were found between 40 primary tumor samples and 12 metastatic lesions in mean levels of IGF-R, IGF-1, or IGF-2. There was a moderately strong correlation between expression of IGF-R and IGF-1, suggesting that autocrine stimulation may be an important mechanism for stimulation of osteosarcoma proliferation.

CONCLUSIONS

A significant proportion of osteosarcoma tumors express IGF-R and ligands. Higher levels of expression were not correlated with metastatic lesions.

MR imaging of symptomatic osteochondromas with pathological correlation

OBJECTIVE

To demonstrate the value of MR imaging in the diagnosis and differentiation of the various symptomatic complications of osteochondromas, providing pathological correlation with emphasis on the usefulness of MR imaging as a single imaging modality in these patients.

DESIGN

We retrospectively reviewed all MR examinations of clinically symptomatic osteochondromas (30 patients) performed at our institution between March 1990 and October 1997.

PATIENTS

Thirty patients had clinically symptomatic osteochondromas during the study period. Twenty patients were male and 10 were female. There were five cases of multiple osteochondromatosis. Pathological correlation was available in 24 patients.

RESULTS AND CONCLUSION

Symptomatic complications included fracture (7%), osseous deformity limiting range of motion (23%), vascular injury (7%), neurological compromise (10%), bursa formation (27%) and malignant transformation (27%). MR imaging was able to diagnose or suggest the etiology for the clinical symptomatology in all cases, demonstrating that it is an ideal imaging modality in the diagnostic evaluation of symptomatic complications of osteochondromas and often avoids the need for further imaging.

Distal ulnar tumours. Results of management by en bloc resection in nine patients and review of the literature

A variety of reconstructive procedures have been suggested for stabilizing the ulnar shaft following resection of the distal ulna for tumour. We present the results of a series of nine distal ulnar tumour resections in which four different stabilization techniques were employed. We based our results on an evaluation of function, pain, motion, strength and instability. We obtained good or excellent results in seven patients treated with a soft tissue stabilization of the ulnar stump. One patient did not undergo any stabilization procedure and scored fair in our system. A further patient who required a radiocarpal arthrodesis also had an inferior result. These results suggest that soft tissue stabilization of the ulnar stump should be performed whenever possible.