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Robert S Bell

Publications and source records attributed to Robert S Bell.

At least 37 records · Page 2Linked to original sources
PubMed2004

Evaluation of clinical utility of BTC-2000 for measuring soft tissue fibrosis.

PURPOSE: To evaluate whether mechanical tissue parameters, specifically laxity (in millimeters) and energy absorption (millimeters of mercury multiplied by millimeters) as measured by the BTC-2000, could discriminate levels of fibrosis severity among patients treated for extremity soft tissue sarcoma by surgery alone; preoperative radiotherapy (RT) and surgery; and surgery followed by postoperative RT. METHODS AND MATERIALS: A total of 41 patients were treated for extremity soft tissue sarcoma by surgery alone (n = 11); preoperative RT (50 Gy in 2-Gy daily fractions) and surgery (n = 15); and surgery followed by postoperative RT (66 Gy in 2-Gy daily fractions; n = 15). Serial fibrosis measurements were evaluated at equal intervals from the midpoint of the surgical incision along the length of the incision. On the basis of the average of these measurements, differences among the three groups were analyzed using analysis of variance. RESULTS: Pair-wise statistically significant differences were found among the three treatment groups for both laxity and energy absorption as determined by the average of all measurements. The treatment difference remained statistically significant even after adjusting for differences based on the untreated contralateral limb and anatomic site (p <0.001 and p = 0.002 for laxity and energy absorption, respectively). CONCLUSION: The biomechanical tissue parameters of laxity and energy absorption discriminated fibrosis severity in patients treated with different RT doses. The BTC-2000 may provide a useful quantitative measure of soft tissue fibrosis.

Combined Modality Therapy↗
PubMed2004

Carbonic anhydrase IX as a marker for poor prognosis in soft tissue sarcoma.

PURPOSE: Hypoxia is associated with malignant progression and poor outcome in several human tumors, including soft tissue sarcoma. Recent studies have suggested that carbonic anhydrase (CA) IX is an intrinsic marker of hypoxia, and that CA IX correlates with poor prognosis in several types of carcinoma. The aim of this study was to quantify the extent of CA IX expression and to investigate whether CA IX is a marker for poor prognosis in soft tissue sarcoma patients at high risk of developing metastasis. EXPERIMENTAL DESIGN: Archival paraffin-embedded blocks were retrieved from 47 patients with deep, large, high-grade soft tissue sarcoma. Sections from two separate and representative tumor areas were immunostained for CA IX, and the CA IX-positive area fraction was quantified by image analysis, excluding areas of normal stroma and necrosis that were identified from serial H&E-stained sections. Patients were then subject to survival analysis. RESULTS: CA IX-positive area fractions of viable tumor tissue varied significantly between tumors (range, 0-0.23; median, 0.004), with positive membranous CA IX staining in 66% (31 of 47) of the tumors. Patients with CA IX-positive tumors had a significantly lower disease-specific and overall survival than patients with CA IX-negative tumors (P = 0.033 and P = 0.044, respectively). CONCLUSIONS: These data suggest that CA IX, a potential intrinsic marker of hypoxia, predicts for poor prognosis in patients with deep, large, high-grade soft tissue sarcoma. Larger studies are required to determine whether CA IX has independent prognostic value in this group of tumors.

Adult↗
PubMed2004

Primary synovial osteochondromatosis of the hip: extracapsular patterns of spread.

OBJECTIVE: To identify patterns of extracapsular extension of synovial osteochondromatosis of the hip. DESIGN AND PATIENTS: Seven cases of synovial osteochondromatosis of the hip were retrospectively reviewed. Imaging performed included conventional radiography ( n=7), arthrography ( n=1), CT ( n=3) and MR imaging ( n=3). Disease extent on imaging was assessed for each patient and the presence of intra-articular effusion, capsular abnormality and osteochondral bodies recorded. The presence and distribution of extra-articular spread was also assessed and correlated with the surgical findings. In all cases diagnosis was confirmed by biopsy, with all patients undergoing tumor resection with or without synovectomy. RESULTS: In five cases (5/7) disease extended beyond the hip capsule, while the remaining two cases (2/7) were confined to the hip joint. These findings were confirmed at surgery. Two distinct patterns of extracapsular spread were identified. The first pattern, noted in three cases, involved tumor extension along iliopsoas. The second pattern, noted in five cases, involved tumor extension along the obturator externus fat plane. In three cases both patterns were present. CONCLUSIONS: Extra-articular spread of synovial osteochondromatosis is common. Patterns of extra-articular spread may be predictable based on involvement of recognized periarticular bursae of the hip joint. Bursal patterns of extra-articular spread include extension into the iliopsoas bursa as well as communication along the obturator externus bursa of the hip.

Adult↗
PubMed2004

Clonogenic survival and cytokinesis-blocked binucleation of skin fibroblasts and normal tissue complications in soft tissue sarcoma patients treated with preoperative radiotherapy.

BACKGROUND AND PURPOSE: To evaluate the clonogenic and cytokinesis-blocked assays in skin fibroblast cultures for their utility as tools for predicting normal tissue responses in soft tissue sarcoma (STS) patients treated with preoperative radiotherapy. PATIENTS AND METHODS: Dermal fibroblast strains were established from skin biopsies of 26 STS patients who received preoperative radiotherapy. Cultures were subjected to the colony forming and cytokinesis-blocked assays after low (approximately 0.02 Gy/min) dose-rate 60Co -irradiation. Fibroblast radiosensitivity was expressed as the dose for 1% clonogenic survival, D0.01, based on colonies/clusters with >or=10 cells. Fibroblast proliferative capability was represented by binucleation index (BNI) and genomic damage was expressed in terms of micronucleus frequency. Wound healing complications (WHC) and subcutaneous fibrosis were the clinical endpoints examined. The ability of each in vitro parameter to detect patients at high risk of a given normal tissue complication was assessed using receiver operating characteristic (ROC) analysis. RESULTS: While fibroblasts from patients without WHC were marginally more radiosensitive than fibroblasts from patients with WHC (P=0.08), the reduction in BNI following a dose of 2.4 Gy was significantly higher in strains from patients without WHC compared to those from patients with WHC (P=0.01). The area under the ROC curve (c-index) is indicative of the power of discrimination of D0.01 and BNI for WHC, and was found to be 0.68 and 0.79, respectively. Subcutaneous fibrosis was not associated with D0.01 (rs=0.09, P=0.66) and the percent reduction in BNI after 2.4 Gy (rs=-0.19, P=0.36). Micronucleus frequency did not reflect differences in normal tissue responses. CONCLUSION: These data suggest that it is the ability of fibroblasts to undergo one-three divisions in vitro following radiation treatment that may reflect the development of wound healing morbidity or subcutaneous fibrosis in this population of patients.

Adult↗
PubMed2004

Functional outcome of endoprosthetic proximal femoral replacement.

Endoprosthetic proximal femur replacement is a well-accepted method for treatment of primary bone tumors; however the functional results of treatment are not well documented. To evaluate functional outcomes, we recorded the Toronto Extremity Salvage Score and Musculoskeletal Tumor Society 1987 and 1993 scores in 29 patients, and also recorded Musculoskeletal Tumor Society scores alone in four more patients treated with endoprosthetic proximal femur replacement. The mean followup was 3 years. Twelve patients had a total hip endoprosthetic proximal femur replacement, and 21 had a bipolar hip endoprosthetic proximal femur replacement. In nine patients, the greater trochanter was attached to the femoral prosthesis. Sixteen patients had an abductor soft tissue repair, and in eight patients, no abductor repair was possible. The mean Musculoskeletal Tumor Society 1987 score was 23.2 +/- 4.1 points of 35 points. The mean Musculoskeletal Tumor Society 1993 score was 67.7 +/- 12.0%. The Toronto Extremity Salvage Score mean was 76.2 +/- 16.2 points of 100 points. Functional scores did not differ significantly between abductor repair types. There was a trend toward less disability in patients with abductor soft tissue repair compared with patients with no abductor repair. Functional results were similar in patients receiving bipolar and total hip replacements.

Arthroplasty, Replacement, Hip↗
PubMed2004

Lymph node metastasis in soft tissue sarcoma in an extremity.

For patients with soft tissue sarcoma in an extremity, the outcome is thought to be poor if lymph node metastasis develops. The purpose of this study was to examine the impact of lymphatic involvement from soft tissue sarcoma on patient survival. Thirty-nine (3.7%) of 1066 patients who had surgery for soft tissue sarcoma in an extremity had lymph node metastases develop. Three (20%) of 15 patients with epithelioid sarcoma, four (19%) of 21 patients with rhabdomyosarcoma, two (11.1%) of 18 patients with clear cell sarcoma, and two (11.1%) of 18 patients with angiosarcoma had lymphatic involvement. Thirty patients who had resection of involved lymph nodes had an estimated 5-year survival of 57%, whereas nine patients treated without surgery all died within 30 months. An estimated 4-year survival of 71% for patients with isolated lymph node metastases was significantly better than 21% for patients with synchronous systemic and lymph node involvement. There was no difference in outcome for patients with isolated lymphatic involvement compared with patients with American Joint Committee on Cancer Stage III extremity sarcomas. These results suggest that long-term survival is possible after surgical resection of lymphatic metastases from soft tissue sarcoma. The American Joint Committee on Cancer should consider separating isolated nodal metastases from systemic involvement in patients with Stage IV sarcoma.

Adolescent↗
PubMed2004

Central giant cell granuloma of the jaws: assessment of cell cycle proteins.

BACKGROUND: Several reports have demonstrated the presence of a high proliferative activity in central giant cell granuloma, raising the possibility that deregulation of the cell cycle may contribute to its pathogenesis. As we identified alterations of cyclin D1 in giant cell tumor of bone, and as there are histologic similarities between central giant cell granuloma and giant cell tumor, we assessed jaw lesions for the presence of similar alterations. METHODS: Formalin-fixed, paraffin-embedded tissue from 29 cases of central giant cell granuloma was assessed for the expression of cyclin D1, cyclin B1, and MIB-1 (Ki-67) using immunohistochemistry. In addition, differential polymerase chain reaction (PCR) was used to determine whether there was cyclin D1 gene amplification. RESULTS: The cyclin D1 gene copy number appeared to be minimally elevated in 31% of the cases. Cyclin D1 protein overexpression was observed in 28 of 29 cases (96.5%). Immunostaining was present predominantly in the nuclei of the giant cells. Cyclin B1 and MIB-1 immunoreactivity was restricted to the mononuclear cells with no staining present in the giant cells. CONCLUSIONS: Cyclin D1 protein overexpression may be involved in the formation of the giant cells and the pathogenesis of central giant cell granuloma. As the distribution of immunostaining is identical to that observed in giant cell tumor of bone, our results support the possibility that central giant cell granuloma of the jaws and giant cell tumor of bone represent a similar disease process that clinically and histologically may have somewhat different features because of differences in the anatomical site of involvement.

Cell Cycle Proteins↗
PubMed2003

Obturator externus bursa: anatomic origin and MR imaging features of pathologic involvement.

PURPOSE: To investigate the anatomy of the obturator externus bursa of the hip and describe the magnetic resonance (MR) imaging features of pathologic involvement. MATERIALS AND METHODS: The authors dissected eight cadaver hemipelvises to assess for the presence of periarticular bursae of the hip and bursal communication with the fascial plane of the obturator externus muscle. In addition, 10 consecutive patients with obturator externus bursa enlargement were prospectively identified with MR imaging. A bursa was considered present when a fluid collection was seen extending along the obturator externus muscle, continuous with the posterior inferior hip joint. The direction, extent, contour, and thickness of the bursa and hip capsule were recorded. Surgical findings were available for eight of the 10 patients, with histopathologic correlation between the bursal lining and hip capsule. RESULTS: At cadaveric dissection, one specimen showed a bursa communicating with and extending from the posteroinferior aspect of the hip joint deep to the obturator externus tendon. In all 10 patients, MR images showed a hip joint effusion with a continuous bursa extending medially and displacing the obturator externus inferiorly. At surgery, a bursa was seen displacing the obturator externus muscle inferiorly and originating from the posteroinferior aspect of the hip joint in all eight patients. Results of pathologic analysis confirmed disease identical to the primary hip abnormality in all eight patients. CONCLUSION: The obturator externus bursa is a potential posteroinferior communication of the hip joint capsule, can be a site of disease spread from the hip joint, and can be accurately identified with MR imaging.

Adult↗
PubMed2003

Low-grade liposarcoma with osteosarcomatous dedifferentiation: radiological and histological features.

We describe the radiological and pathological findings of a rare case of a low-grade liposarcoma associated with a high-grade osteosarcomatous component in a 78-year-old woman. Pre-operative imaging demonstrated a well-encapsulated homogeneous fatty tumour in the right buttock deep to the gluteal musculature. Centrally within the fatty tumour a region of increased soft tissue attenuation on CT and heterogeneous high signal on fat-saturated T2-weighted MRI was seen with amorphous calcification/ossification. Histological assessment revealed a low-grade liposarcoma containing an area of dedifferentiation that resembled an osteosarcoma. We describe the radiological-pathological findings in this rarely reported clinical entity and discuss the differential diagnosis of calcification within lipomatous tumours.

Aged↗
PubMed2003

The influence of anatomic location on outcome in patients with soft tissue sarcoma of the extremity.

BACKGROUND: The anatomic location of an extremity soft tissue sarcoma may influence the patient's presentation, management, and local and systemic recurrence rates. The objective of this study was to compare the presentation, management, and outcome of patients with soft tissue sarcomas of the upper extremity and the lower extremity. METHODS: Prospectively collected data from patients who underwent limb-sparing surgery for extremity soft tissue sarcoma between January, 1986 and April, 1997 were analyzed. Local recurrence free rates and metastasis free rates were calculated using the method of Kaplan and Meier. Univariate and multivariate analyses of potential predictive factors were evaluated with the log-rank test and the Cox proportional hazards model. RESULTS: Of 480 eligible patients, 48 patients (10.0%) had a local recurrence, and 131 patients (27.3%) developed distant metastasis. The median follow-up of survivors was 4.8 years (range, 0.1-12.9 years). Patients with upper extremity tumors had smaller lesions (6.0 cm vs. 9.3 cm; P < 0.001), more often underwent unplanned excision before referral (89 patients [64.0%] vs. 160 patients [46.9%]; P < 0.001), and less often received radiotherapy (98 patients [70.5%] vs. 289 patients [84.8%]; P < 0.001). The 5-year local recurrence free rate was 82% for patients with sarcomas of the upper extremity and 93% for patients with sarcomas of the lower extremity (P = 0.002). The 5-year metastasis free rate was 82% for patients with sarcomas of the upper extremity and 69% for patients with sarcomas of the lower extremity (P = 0.013). CONCLUSIONS: Local recurrence was more frequent in patients who had sarcomas of the upper extremity compared with patients who had sarcomas of the lower extremity. Factors that contributed to this difference included histologic type, the use of radiotherapy, and local anatomy. Metastasis was more frequent among patients with sarcomas of the lower extremity, because those tumors tended to be large and deeper compared with upper extremity tumors.

Adolescent↗
PubMed2003

Effect of radiation and cell implantation on wound healing in a rat model.

BACKGROUND AND OBJECTIVES: Having shown that intra-dermal injection of fibroblasts decreases the effect of radiation on healing of superficial wounds, we now test the effect of fibroblasts and syngeneic marrow stromal cells on irradiated deep and superficial wounds. METHODS: Wistar rats received bilateral buttock irradiation followed by partial excision of the gluteus muscle bilaterally. In Protocol 1, one irradiated wound was treated with 1.2 x 10(7) autologous cells injected intra-dermally. In Protocol 2, the experimental side was treated with a fibrin and autologous cell implant (1.2 x 10(7) cells). Twenty-one days later, wound mechanical characteristics were tested. In Protocol 3, the effect of pooled marrow stromal cells on healing of superficial irradiated wounds in Lewis rats was similarly tested. RESULTS: The fibrin-fibroblast implant (Protocol 2) had no effect on wound mechanics. Superficial injection of fibroblasts (Protocol 1) significantly improved wound breaking strength when compared to the control group (mean +/- SEM, breaking strength: treated 504.6 +/- 37.0 g vs. control 353.4 +/- 35.2 g, P = 0.005). The dermal injection of marrow stromal cells also resulted in marked increases in breaking strength (mean +/- SEM, breaking strength: treated 338.5 +/- 39.9 g vs. control 187.1 +/- 12.0 g, P < 0.01). In both Protocols 1 and 3, ultimate tensile strength and toughness were increased in the side receiving cell transplantation. CONCLUSIONS: Cell implantation holds promise for decreasing the effect of radiation on healing of irradiated wounds.

Animals↗
PubMed2003

Large segment allograft survival is improved with intramedullary cement.

BACKGROUND AND OBJECTIVES: The most common cause of failure in large segment bone allografts used for oncologic reconstruction is allograft fracture. Reinforcement with pressurized intramedullary cement may improve the mechanical properties of allografts. METHODS: We reviewed the prospectively collected records of 45 patients who underwent en bloc resection of an extremity bone tumor and reconstruction using an allograft with intramedullary cement. RESULTS: Seven allografts were used for arthrodesis, 20 were intercalary, and 18 were osteochondral. Twenty eight of 45 patients were alive at a mean 5.8 years (SD 1.9; range 3-11.2) with 24 allografts in situ. In these 45 patients, there were four allograft fractures and four infections. Six of these complications resulted in allograft removal. The estimated 5-year allograft survival rate was 86% (95% confidence interval 74-98%). Seven patients required secondary autogenous bone grafting for non-unions. Function measured by the Toronto Extremity Salvage Score and the 1987 and 1993 Musculoskeletal Tumor Society Rating Scales demonstrated a consistent pattern with worse function in patients with osteochondral allografts and best function with intercalary allografts. CONCLUSIONS: These results suggest the addition of intramedullary cement to large segment bone allografts improves their survival by decreasing the fracture risk, particularly for allografts used for arthrodesis and intercalary reconstructions.

Adolescent↗
PubMed2003

Work status after distal femoral Kotz reconstruction for malignant tumors of bone.

OBJECTIVE: To determine the proportion of patients who experienced altered work status after reconstruction with a modular tumor prosthesis and adjuvant chemotherapy for primary sarcoma of the distal femur. DESIGN: We reviewed an institution's tumor database and patients' charts. Disability and work status data were collected preoperatively, at 1 year and 2 years postoperatively and at final follow-up. SETTING: Acute-care teaching hospital in Ontario, Canada. PARTICIPANTS: Thirty-six eligible patients. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Work status was plotted over time to identify unexpected deviations (based on age and preoperative status), and subjects were assigned to altered work status (defined by detrimental changes in productivity, eg, change from full-time work to not working) or expected work status (defined by ongoing work or students progressing to higher education). Disability was measured with the Toronto Extremity Salvage Score and the Musculoskeletal Tumor Society score. RESULTS: Nine patients (25%) experienced altered work status. There were no significant differences in disability ratings or demographic information between the 2 groups. Baseline job demand and living environment (rural vs urban, P=.001) were predictive by logistic regression. CONCLUSIONS: Patients with physically demanding jobs, and those living rurally, are at greatest risk for altered work status.

Adolescent↗
PubMed2003

Acetabular metastases: planning for reconstruction and review of results.

The treatment of acetabular bone metastases presents numerous clinical challenges including the necessity for careful patient selection for surgery, determination of the extent of bone destruction, and providing the patient with stable surgical reconstruction of the pelvis. There are relatively few patient series reported in the literature to inform treatment planning, surgical reconstruction techniques, and patient outcomes. We describe a rationale for assessment of patients with acetabular metastases and options for reconstruction. The three general principles for surgical treatment of metastatic bone disease (tumor removal, filling of the resultant bone defect, and bypass of the defect) are defined for acetabular metastases. The results of surgical treatment are described with reference to recent articles in the literature. The reconstruction of acetabular metastatic disease is a major surgical procedure with a significant risk of complications. The surgeon must be certain that the patient's longevity and potential improvement in quality of life justify the risk of the operation.

Acetabulum↗
PubMed2003

Cyclin alterations in giant cell tumor of bone.

Cyclins play an important role in regulating the passage of dividing cells through critical checkpoints in the cell cycle. Because alterations of several cyclins, especially cyclin D1, have been implicated in the development of many human neoplasms, we examined 32 cases of giant cell tumor of long bones for cyclin D1 gene amplification and protein overexpression using differential polymerase chain reaction and immunohistochemistry, respectively. In addition, the expression of cyclin D3, cyclin B1, and the proliferation-associated antigen Ki-67 (MIB-1) was assessed immunohistochemically. Low-level cyclin D1 gene amplification was detected in 61% of giant cell tumor cases. All tumors showed cyclin D1, cyclin D3, cyclin B1, and Ki-67 (MIB-1) staining; however, the distribution was very characteristic. Cyclin D1 protein expression was seen predominantly in the nuclei of the giant cells, with occasional mononuclear cells staining. There was no correlation between cyclin D1 gene amplification and protein overexpression. Cyclin D3 staining showed a similar distribution, with 88% of cases showing protein overexpression. Cyclin D1 and/or D3 staining in the giant cells was never associated with staining for either cyclin B1 or Ki-67 (MIB-1), as the expression of the latter two proteins was restricted to the mononuclear cells. Cyclin B1 overexpression was seen in 44% of cases. Ki-67 (MIB-1) staining was present in all cases, and between 10 to 50% of the mononuclear cells were positive. These results suggest that alterations in cyclin D1 and/or D3 might play a role in the pathogenesis of giant cell tumor of bone.

Adolescent↗
PubMed2003

Osseous invasion by soft-tissue sarcoma: assessment with MR imaging.

PURPOSE: To assess magnetic resonance (MR) imaging signs and overall accuracy of MR imaging for detection of osseous invasion by soft-tissue sarcoma, with histopathologic correlation as the reference standard. MATERIALS AND METHODS: Preoperative MR images (1.5 T, transverse and longitudinal planes, T1 and T2 weighted) of 56 osseous sites in 51 patients who underwent bone resection at surgery for soft-tissue sarcoma were assessed retrospectively for signs of osseous invasion, by consensus of two readers who were blinded to clinical and histopathologic findings. Delay between MR imaging and surgery averaged 34 days (range, 2-112 days). MR signs assessed included osseous abutment by tumor, maximal diameter of osseous abutment, extent of circumferential abutment of long bones (<25%, 25%-50%, >50%), cortical destruction, and cortical and medullary signal intensity change on T1- and T2-weighted images. Imaging findings were correlated with histopathologic findings. Sensitivities, specificities, positive and negative predictive values (PPV, NPV), and P values were calculated. RESULTS: Eleven sites (20%) showed osseous invasion histologically (two, cortical; nine, both cortical and medullary). Tumor abutted bone at 44 lesion sites (sensitivity, 100%; specificity, 27%). Maximal diameter of osseous abutment and extent of circumferential abutment did not significantly affect osseous invasion (P =.09 and.11, respectively). On T1- and T2-weighted images, 13 lesion sites showed cortical signal intensity change (sensitivity, 100%; specificity, 96%) and 10 showed cortical destruction (sensitivity, 82%; specificity, 98%). Eleven sites showed decreased medullary T1 signal intensity (sensitivity, 100%; specificity, 96%), and 12 showed increased medullary T2 signal intensity (sensitivity, 100%; specificity, 94%). MR imaging overall had a sensitivity of 100%, specificity of 93%, PPV of 79%, and NPV of 100% for detection of osseous invasion on the basis of any finding of cortical destruction or cortical or medullary signal intensity change on T1- or T2-weighted images (P <.001). CONCLUSION: On T1- and T2-weighted MR images, findings of cortical and medullary signal intensity change and cortical destruction were sensitive and specific for detection of osseous invasion by soft-tissue sarcoma.

Adolescent↗
PubMed2003

Soft tissue sarcomas of adults: state of the translational science.

Sarcomas--like leukemias, which are also mesodermal malignancies--carry biological significance disproportionate to their clinical frequency. Identification of mutations and translocations associated with these tumors has illuminated aberrant signaling pathways that cause these diseases, determine their behavior, and are therapeutic targets. Activated receptor-associated tyrosine kinase c-kit, mutated in most gastrointestinal stromal tumors, has proven a clinically effective target for enzyme inhibition. A translocation involving a single gene family, consisting of EWS and related genes, has been identified in five different sarcomas, and its chimeric protein products could prove similarly amenable to inhibitors. Resolution of the histopathological complexity is being aided by data from molecular and chromosomal characterization. Improvements in imaging, definition of prognostic factors, and surgical and radiotherapeutic treatment have resulted in improved local control. Continued progress will depend on further adapting the rapidly evolving technologies of genomics and proteomics. It will also depend upon accurate histopathological diagnosis based on validated reagents and consistent methodologies applied to adequate tissue samples derived from patients with complete clinical data. Finally, multicenter, coordinated trials, such as those that occurred with assessment of imatinib mesylate in metastatic gastrointestinal stromal tumors, will assure the most rapid reductions in morbidity and mortality.

Adult↗