Richard D. Lackman

Endoprosthetic reconstructions: Results of long-term followup of 139 patients

Our primary goal in doing this study was to determine the effect of prosthesis location, patient age, periprosthetic infection, and primary versus revision placement on endoprosthetic survival. We also examined our endoprosthetic survival rates and reasons for failure. We retrospectively studied 139 endoprosthetic reconstructions performed between 1984 and 2002, including 57 distal femur, 27 proximal femur, 26 proximal tibia, 17 proximal humerus, 4 distal humerus, 3 total scapula, 3 total femur, and 2 total humerus reconstructions. Location of reconstruction and presence of periprosthetic infection significantly affected endoprosthetic survival. Survival was not affected by patient age or primary versus revision placement. Overall, Kaplan-Meier event-free endoprosthetic survival was 86%, 80%, and 69% at 3, 5, and 10-year followup. The trend for endoprosthetic survival from best to worst was proximal femur, proximal humerus, distal femur, proximal tibia, and distal humerus. Reasons for failure included mechanical failure (eight patients), tumor recurrence (eight patients), aseptic loosening (six patients), dislocation (two patients), periprosthetic infection (two patients), and endoprosthetic malalignment (one patient). Our periprosthetic infection rate was 2.2%. The local recurrence rate in patients treated for primary malignant tumors was 6.8%, similar to previous limb-salvage and amputation studies. Overall, we have found that endoprosthetic reconstruction is a reliable limb-salvage technique. Level of Evidence: Therapeutic study, Level IV-2 (case series). See the Guidelines for Authors for a complete description of levels of evidence.

Phospho-S6 ribosomal protein : a potential new predictive sarcoma marker for targeted mTOR therapy

Metastatic sarcomas are commonly resistant to chemotherapy. The serine/threonine kinase, mammalian target of rapamycin (mTOR), is a protein kinase of the phosphatidylinositol 3-kinase (PI3K)/AKT signaling pathway thought to have a key role in controlling cancer growth and thus is an important target for cancer therapy. Several inhibitors of mTOR are in clinical trials, including AP23573, which is being tested on metastatic sarcomas and other tumors. We hypothesized that a marker for the activity of mTOR, phosphorylated S6 ribosomal protein, would be predictive of clinical response to the drug, that is, high tumor expression would signify better response than low expression. This was a blinded study. Of 26 patients treated, 20 remained on study, with available paraffin blocks. Fourteen patients received AP23573 alone and six patients received AP23573 in combination with adriamycin. An antibody to the phosphorylated S6 ribosomal protein was used to stain the tumors, all high-grade sarcomas. Pretreatment biopsy or resection material was tested: the original tumor (n=6) or tumor recurrence/metastasis (n=14); either of these may have been after treatment with other agents. Staining was scored for both quantity/percentage of tumor cells and intensity. Scoring was performed without knowledge of tumor response. Staining quantity could be categorized into two natural groups: high expressors (≥20% of tumor cells, 11 cases) and low expressors (0–10% of tumor cells, 9 cases). The high-expression group had eight stable and three progressive cases (73% stable disease); the low-expression group had three stable and six progressive cases (67% progressive disease). Chi-square analysis showed statistical significance (P≤0.05) at this initial cutoff (10%) selected blindly. The level of phosphorylated S6 ribosomal protein expression was predictive of early tumor response to the mTOR inhibitor, suggesting that this is a promising new predictive sarcoma marker for targeted mTOR inhibitor therapy.

The treatment of sacral giant-cell tumours by serial arterial embolisation

Giant-cell tumours of the sacrum are difficult to treat. Surgery carries a high risk of morbidity, local recurrence and mortality. Radiation is effective in some patients, but has a risk of malignant change. We evaluated the effectiveness of serial arterial embolisation as an alternative to surgery. Five patients with giant-cell tumours of the sacrum which had been primarily treated by serial embolisation were retrospectively reviewed for changes in the size of the tumour. In four the symptoms resolved with full return of function and arrest in the growth of the tumour. They remained free from growth, recurrence, or metastases at follow-up (4 to 17 years). One patient died from metastatic disease within 18 months of the initial diagnosis.

Intralesional curettage for grades II and III giant cell tumors of bone.

Grade III Campanacci lesions are traditionally treated with wide resections based on their postulated aggressiveness and potential for local recurrence and metastasis. The purpose of this study was to determine if there was a difference in local recurrence rates of Grade II and III lesions treated with intralesional curettage, burring, phenol cauterization, and polymethylmethacrylate application. Sixty-three patients (26 Campanacci Grade II and 37 Grade III lesions) met the inclusion criteria. No pathologic fractures, including intraarticular fractures, were included in this study. Followup averaged 108 months (range, 25–259 months). The overall local recurrence rate was 6% (4 of 63 patients), with no observed difference between Grade II and III lesions. The average Musculoskeletal Tumor Society functional score was 27.9/30 (93%). The mean range of motion of the adjacent joint was 97%. Patients with radiographic signs of osteoarthritis before treatment did not show substantial progression, and only one patient developed radiographic signs of degenerative arthritis postoperatively. Our distal metastatic rate was 3.2%. These data support the use of intralesional curettage and burring with adjuvant phenol and polymethylmethacrylate even in Grade III lesions, in the absence of pathologic fracture, regardless of the presence or extent of extraosseous extension. Level of Evidence: Therapeutic study, Level III-1 (retrospective cohort). See the Guidelines for Authors for a complete description of levels of evidence.

Serial arterial embolization for large sacral giant-cell tumors: mid- to long-term results.

Study Design. Level III retrospective case series with historical controls. Objective. To evaluate the mid- to long-term outcomes of serial arterial embolization as a primary treatment modality for large sacral giant-cell tumors (SGCT). Summary of Background Data. Giant-cell tumors are potentially aggressive benign tumors that can cause significant morbidity and may occasionally prove lethal. Large GCTs in the sacrum present a significant challenge, and treatment methods, including surgical resection and radiation, are associated with morbid complications and high recurrence rates. This report presents the mid- to long-term follow-up results of our cases of SGCT treated with serial arterial embolization. Methods. Nine consecutive patients with biopsy-proven SGCTs received initial primary treatment with serial arterial embolization between 1984 and 2006. All patients underwent angiography and selective arterial embolization at the time of diagnosis, followed by repeat embolization every 6 weeks until no new vessels were noted, and then at 6 and 18 months following stabilization of the lesion. Patients were closely monitored with MRI and/or CT every 6 months for 5 years and annually thereafter. Functional outcomes were measured using the 1993 Musculoskeletal Tumor Society Rating Scale (MSTS93). Results. The mean duration of follow-up in this series was 8.96 years (median, 7.8 years; range, 3.8–21.2 years). No progression was noted in 7 of the 9 cases. Two cases experienced tumor progression of less than 1 cm early in the treatment course and continued to remain asymptomatic. Adjuvant radiation therapy provided local control in 1 of these cases, while radiation and chemotherapy failed in the other case with ultimate mortality. All patients demonstrated substantial pain relief. Cross-sectional MSTS93 scores were obtained in the 8 surviving patients at their most recent follow-up visit with a mean score of 29/30. Conclusions. Serial arterial embolization is a useful primary treatment modality for large SGCTs given the favorable long-term results and potential morbidity of alternative treatments.

Fibular reconstruction for giant cell tumor of the distal radius

The management of giant cell tumors involving the distal radius has always been a difficult problem. After resection to eradicate a primary or recurrent lesion, transplantation of a nonvascularized fibular autograft was used in 12 patients. Of these patients, ten had good to excellent functional results. The procedure can restore a functionally useful wrist.

Clinical utility of percutaneous biopsies of musculoskeletal tumors

Percutaneous biopsies are frequently used for musculoskeletal lesions. We suspect published accuracy rates (80-97%) overestimate clinical utility. We retrospectively reviewed 120 consecutive percutaneous biopsies performed by interventional radiologists at our institution. Patients underwent core biopsy, fine-needle aspiration (FNA), or both. The biopsy interpretations were considered clinically useful if they allowed proper treatment to proceed and not useful if they were nondiagnostic or if surgical specimens disagreed with percutaneous specimen. Patients were categorized by biopsy type, tissue type, and tumor type. Ninety of 120 percutaneous biopsies were clinically useful, 27 were nondiagnostic, and three were incorrect; in these latter 30 patients we proceeded to open biopsy. Patients with both biopsies had clinically useful results (80.6%) more often than FNA or core alone(68.0% and 66.7%, respectively). Biopsies of bone lesions were clinically useful more often than those of soft tissue. Myxoid histology was associated with decreased clinical accuracy. Clinical utility was independent of tumor type. No single characteristic predicted increased probability of open biopsy. The clinical utility rate was acceptable, but below published accuracy rates. The combination of both biopsies was better than FNA alone. Myxoid findings rarely helped to guide definitive treatment. Treatment decision making requires balancing biopsy results with clinical data.Level of Evidence: Diagnostic study, level IV. See Guidelines for Authors for a complete description of levels of evidence.

Bipolar proximal femoral replacement prostheses for musculoskeletal neoplasms.

While bipolar proximal femoral replacement prostheses (PFRP) have become a common treatment for tumors of the proximal femur, long-term results are not specified in the literature. The objective was to determine the complication and revision rates of bipolar PFRP and compare them to historical controls of bipolar hemiarthroplasties for nontumor indications. Information was retrospectively collected on 62 patients who received bipolar PFRP with cemented diaphyseal stems for primary or metastatic disease of the proximal femur from 1981 to 2003. Mean followup was 5 years. Twelve of 62 (19%) bipolar PFRPs underwent revision. Aseptic loosening was the most common complication with six (10%) undergoing revision. None were converted to THA due to acetabular erosion. Three patients (5%) had problems with dislocation and three (5%) had deep infections. Mean MSTS functional rating was 71% of normal function. The limb salvage rate was 98% and the 5-year event-free prosthetic survival was 79%. Bipolar PFRPs were found to have higher revision, dislocation, and deep infection rates compared to bipolar hemiarthroplasty for nontumor indications, but a lower rate of conversion to THA due to acetabular erosion. Bipolar PFRPs have good long-term durability with some complications, but are able to preserve the limb and provide good function for patients.Level of Evidence: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Musculoskeletal desmoid tumors.

Desmoid tumors are benign tumors that exhibit varying degrees of local aggressiveness and diverse growth patterns. Magnetic resonance imaging remains the modality of choice for assessment of the nature and size of the soft-tissue lesion and involvement of surrounding structures. Treatment strategies include surgery, chemotherapy, hormonal therapy, and radiation therapy, either individually or in combination. Despite the benign nature of these tumors, multidisciplinary care is needed to provide combined treatment options. Chemotherapy in low doses is an excellent first-round treatment in any patient in whom contemplated local treatment may produce local morbidity and adjacent tissue injury.

Atypical lipomatous masses of the extremities: Outcome of surgical treatment

Atypical lipomatous tumors occur predominantly in middle-aged patients and often present as painless, slow-growing masses in the extremities. The clinical outcomes of surgically treated superficial or deep atypical lipomas of the extremities were reviewed. Thirty-one patients were included in this study. There were 16 men and 15 women, with an average age of 57 years (range, 32–87 years). The mean followup was 7 years (range, 1–28.8 years). Twenty-five tumors occurred in the lower extremity and six in the upper extremity. Sixteen patients (52%) had a recurrence at an average of 4.7 years after resection. Twelve (39%) patients required additional surgical procedures to treat their tumor. Occurrence of a deep lesion and positive margins at the time of the initial surgery correlated closely with the rate of recurrence and need for additional surgical treatment. Dedifferentiation to high-grade liposarcoma developed in four (13%) patients. Atypical lipomas have a high propensity for local recurrence and a potential for malignant dedifferentiation. Patients with atypical lipomas require careful evaluation, complete surgical excision when possible, and close clinical followup extending beyond 5 years.