Satoshi Tsukushi

MRI Features in the Differentiation of Malignant Peripheral Nerve Sheath Tumors and Neurofibromas

OBJECTIVE The objective of this study was to identify the MRI criteria that best differentiate malignant peripheral nerve sheath tumors from benign neurofibromas. MATERIALS AND METHODS We retrospectively analyzed MR images obtained for 41 histologically diagnosed cases of malignant peripheral nerve sheath tumor and 20 cases of neurofibroma that had been treated at four tertiary institutions. Twenty of the patients with malignant peripheral nerve sheath tumors and 14 patients with neurofibromas developed the disease in association with neurofibromatosis 1. The MR images were evaluated with regard to tumor size, signal intensity, heterogeneity of T1- and T2-weighted MR images, enhancement pattern, definition of margins, presence of perilesional edemalike zone, and presence of intratumoral cystic lesions. RESULTS Significant differences between malignant peripheral nerve sheath tumors and neurofibromas were noted for the largest dimension of the mass, peripheral enhancement pattern, perilesional edemalike zone, and intratumoral cystic lesion. In cases associated with neurofibromatosis 1, heterogenicity on T1-weighted images was also significant in differentiating neurofibroma from malignant peripheral nerve sheath tumor. The presence of two or more of the four features suggestive of malignancy indicated malignant peripheral nerve sheath tumor with a sensitivity of 61% and a specificity of 90%. CONCLUSION The MR features described in this study are useful for distinguishing malignant peripheral nerve sheath tumors from neurofibromas. If a tumor has two or more of the four statistically significant features, it can be considered to be highly suspicious of malignancy and should be subjected to a biopsy for early diagnosis.

Clinical Outcome of Sacral Chordoma With Carbon Ion Radiotherapy Compared With Surgery

PURPOSE To evaluate the efficacy, post-treatment function, toxicity, and complications of carbon ion radiotherapy (RT) for sacral chordoma compared with surgery. METHODS AND MATERIALS The records of 17 primary sacral chordoma patients treated since 1990 with surgery (n = 10) or carbon ion RT (n = 7) were retrospectively analyzed for disease-specific survival, local recurrence-free survival, complications, and functional outcome. The applied carbon ion dose ranged from 54.0 Gray equivalent (GyE) to 73.6 GyE (median 70.4). RESULTS The mean age at treatment was 55 years for the surgery group and 65 years for the carbon ion RT group. The median duration of follow-up was 76 months for the surgery group and 49 months for the carbon ion RT group. The local recurrence-free survival rate at 5 years was 62.5% for the surgery and 100% for the carbon ion RT group, and the disease-specific survival rate at 5 years was 85.7% and 53.3%, respectively. Urinary-anorectal function worsened in 6 patients (60%) in the surgery group, but it was unchanged in all the patients who had undergone carbon ion RT. Postoperative wound complications requiring reoperation occurred in 3 patients (30%) after surgery and in 1 patient (14%) after carbon ion RT. The functional outcome evaluated using the Musculoskeletal Tumor Society scoring system revealed 55% in the surgery group and 75% in the carbon ion RT group. Of the six factors in this scoring system, the carbon ion RT group had significantly greater scores in emotional acceptance than did the surgery group. CONCLUSION Carbon ion RT results in a high local control rate and preservation of urinary-anorectal function compared with surgery.

Successful Treatment With Meloxicam, a Cyclooxygenase-2 Inhibitor, of Patients With Extra-Abdominal Desmoid Tumors: A Pilot Study

TO THE EDITOR: Extra-abdominal desmoid tumors, which are usually sporadic in nature, occur across a wide age range and can arise at virtually any body site, but are mainly found in the extremities and girdles, chest, abdominal wall, and neck. Local growth and invasion may result in pain, deformity, and functional impairment. The potential morbidity of surgery and radiation therapy has led investigators to assess the role of noncytotoxic and cytotoxic chemotherapy. Because extra-abdominal desmoid tumors rarely cause disease-specific death, pharmacologic treatment with fewer complications is desirable. Cyclooxygenase-2 (COX-2) is implicated as a factor in tumor initiation in colonic neoplasia and has also been demonstrated to play a role in the growth of desmoid tumors, with pharmacologic blockade of COX resulting in decreased cell proliferation in desmoid cell cultures in vitro, and COX-2 blockade resulting in smaller desmoid tumors in an in vivo mouse model. Taken together, these results led us to hypothesize that COX-2 might represent an attractive therapeutic target in desmoid tumors, and that meloxicam may have a marked efficacy compared with conventional nonselective nonsteroidal anti-inflammatory drugs. Between 1991 and 2003, excluding those with intra-abdominal, familial adenomatous polyposis–associated, and unresectable tumors, 30 patients were treated with surgery in our institutions. Because the recurrence rate of this group was high (53%) even with a mostly negative surgical margin, since 2003, 22 consecutive extra-abdominal patients have been prospectively treated with meloxicam. Patients with intra-abdominal desmoid tumors and patients less than 16 years of age were excluded. Meloxicam was administered orally at 10 mg/ day. There were no patients with a known history of gastritis or gastric ulcer, and none were receiving hormonal medications. Baseline imaging of desmoid tumors by MRI was obtained before starting treatment. Patients treated with meloxicam have been followed with physical examinations and magnetic resonance imaging and/or computed tomography at the outpatient unit of our department of orthopedic surgery every 3 to 6 months. The efficacy of meloxicam was evaluated according to Response Evaluation Criteria in Solid Tumors (RECIST) measured with magnetic resonance imaging at the latest follow-up. All patients signed an informed consent form, and the protocol was approved by the institutional review board of our

Clavicula pro humero reconstruction after wide resection of the proximal humerus

The optimal reconstruction procedure after resection of proximal humeral bone tumors is controversial. We performed clavicula pro humero reconstruction in seven consecutive patients after wide resection of malignant proximal humerus tumors to determine the functional outcomes and to clarify whether this procedure could reduce the occurrence of complications. The histologic diagnoses were conventional osteosarcoma in four patients, chondrosarcoma in two, and parosteal osteosarcoma in one. Postoperative function was assessed with the Musculoskeletal Tumor Society upper extremities scale and an evaluation chart for activities of daily living. The mean Musculoskeletal Tumor Society score was 69%. Stable results were obtained regardless of the extent of the resection, and the results as a flail shoulder were satisfactory. The mean daily activity rating was approximately 80%. The activities of daily living functional rating was better (92%) when the nondominant hand was affected compared with the dominant hand (69%). Bony union was achieved in all seven patients. We observed no instances of infection, fracture, or nonunion. The clavicula pro humero reconstruction is a useful procedure that could reduce the occurrence of complications, especially in young patients and in patients with involvement of the nondominant arm.Level of Evidence: Therapeutic study, Level IV (case series). See the Guidelines for Authors for a complete description of levels of evidence.

Osteosarcoma in the elderly over 60 years: A multicenter study by the Japanese musculoskeletal oncology group†

Few studies have described the characteristics and prognostic factors of osteosarcoma patients aged over 60 years.

Soft Tissue Sarcomas of the Chest Wall

Introduction: Soft tissue sarcomas originating from the chest wall include in their definition those originating from the trunk and, in many cases, are analyzed together with retroperitoneal tumors whose clinical results differ, with only a few detailed reports on such tumors strictly limited to the chest wall available. The main purpose of this study was to evaluate the clinical outcomes for patients with chest wall soft tissue sarcomas. Methods: A retrospective review of 44 surgically treated patients was conducted from 1992 to 2006. The median age of the patients was 51.8 years. The median follow-up time was 56.7 months. Twenty-two sarcomas (50.0%) were high-grade, and 22 (50.0%) were low-grade. Of the 44 patients, 31 (70.1%) had previously undergone unplanned excision elsewhere. Histologic examinations of the surgical margins, and oncological outcome for each patient were collected and analyzed. Results: Twenty-six (59.1%) patients were continuously free of disease, 12 were alive and currently free of disease, three were alive with metastasis, and three had died. Local recurrence developed in five patients. The overall survival rate at 5 years was 88.5%. Local recurrence-free survival rate at 5 years was 88.5%. Univariate analyses disclosed age (p < 0.05), high-grade malignancy (p < 0.05), and local recurrence (p < 0.05) as independent predictors of death. Histopathologic examination of the specimens showed that two patients had evidence of bone invasion. Conclusions: The clinical behavior of the chest wall soft tissue sarcomas is similar to that of extremity sarcomas. High-grade tumors are more likely to require a muscle transfer, and it is often very difficult to achieve local control of them in view of their anatomic characteristics. Considering the high local control rate in this study, they are best controlled by adequate wide surgical resection.

Osteochondral destruction in pigmented villonodular synovitis during the clinical course.

Objective. In pigmented villonodular synovitis (PVNS), some cases recur and progress to osteochondral destruction. The aim of our study was to clarify the occurrence of osteochondral destruction according to the location of PVNS during the clinical course. Methods. Seventy-two patients with PVNS (43 female, 29 male) with a mean age of 40 years (range 3–87 yrs) had been referred to our institutions. Factors influencing the occurrence of osteochondral destruction were investigated. Results. Mean followup was 60 months (range 12–190 mo). Adjacent bone change occurred in 24 (42%) of 57 patients, who were evaluated at the time of the first consultation. Eight (89%) of 9 patients with hip lesions initially had bone lesions, significantly more frequently than those with other lesions (p = 0.038). Duration of symptoms was significantly correlated with the occurrence of bone lesions in diffuse knee lesions (p = 0.005). During followup, patients with location in the knee had a significantly higher incidence of osteoarthritic change (73%) compared to those with foot and ankle involvement (p = 0.027). Re-operation was more frequently required for knee lesions due to the high recurrence rate (32%). Patients who required re-operation had significantly more marked osteoarthritic change in knees (p = 0.001) during followup than those who did not. Conclusion. For PVNS arising in knees, repeated recurrences followed by re-operation resulted in the progression of osteoarthritic change. PVNS arising in hips, feet, and ankles developed bone lesions initially, probably due to the limited volume of these joints. The indications for re-operation for recurrent knee lesions require careful consideration regarding progression of osteoarthritic change.

Osteochondroma with metaphyseal abnormalities after total body irradiation followed by stem cell transplantation.

The occurrence of osteochondroma after total body irradiation (TBI) followed by stem cell transplantation (SCT) in our institutions was described, and its clinical significance discussed. Of 305 cases treated with SCT using TBI conditioning from 1980 to 2001, 4 cases of osteochondroma were identified on clinical examination. Mean age at the time of TBI was 4.4 years (range, 1.6 to 8.0). One patient developed multiple osteochondromas. All 4 cases showed metaphyseal abnormalities, including sclerotic metaphyseal lesion, fraying, and longitudinal striation, in the area where osteochondromas occurred. Only 1 patient required resection of the tumor due to pain. Two cases had other skeletal abnormalities including slipped capital femoral epiphysis and valgus-knee deformity, which required surgical intervention to prevent or correct these deformities. Osteochondroma is one of the complications developing after TBI, possibly concurrently with the metaphyseal abnormalities as seen on radiographs. However, clinical problems arising from osteochondroma are minimal, and surgical intervention is necessary in limited cases.

Transition of Treatment for Patients with Extra-Abdominal Desmoid Tumors: Nagoya University Modality

Treatment modalities for desmoid tumors have been changed because of the high recurrence rate, even after wide resection, and some cases experience spontaneous self-regression during clinical course. The treatment modality in our institutions before 2003 was surgical resection with wide surgical margin, however, meloxicam, which is a NSAID and a selective COX-2 inhibitor has been applied consecutively since 2003. We reviewed the previously reported outcomes of surgical and conservative treatment in our institutions. Among 30 patients receiving surgical treatment, 16 (53%) recurred. Younger age (p < 0.05) was a significant poor factor. According to RECIST for meloxicam treatment, CR was in one, PR in 10, SD in eight, PD in one evaluated at 2011. Older age (p < 0.01) was significantly associated with good outcome for meloxicam treatment. Results of the previous study indicated that surgical treatment alone could not control desmoid tumors, even with negative surgical margin. Considering the functional impairment resulting from surgery with negative surgical margin, a conservative and effective treatment modality with fewer complications is desired. Conservative treatment with meloxicam is a promising novel modality for patients with extra-abdominal desmoid tumors.

Regenerating the fibula with beta-tricalcium phosphate minimizes morbidity after fibula resection.

The aim of this study was to assess the radiologic and clinical outcome when beta-tricalcium phosphate is used as a bone graft substitute to backfill the fibular defect that is created by harvesting the fibula. Fourteen patients who had fibula resections to be used as bone grafts for bone tumor resections were assessed radiographically. Callus formation bridging the beta-tricalcium phosphate was seen in 12 of 14 patients at an average of 1.4 months after surgery. In these 12 patients the beta-tricalcium phosphate mostly was absorbed and replaced by newly formed bone at an average of 9.3 months after surgery. In all children, beta-tricalcium phosphate was replaced by newly formed bone at an average of 3.2 months after surgery. Only one adult patient had complete regeneration of the fibula. Few patients had continuity between the regenerated fibula and the native fibula. In one patient in whom free vascularized fibula was harvested, regeneration of the fibula was not observed. Clinical functional outcome was not correlated with successful fibula regeneration and union with the native fibula, as determined using radiographs. The results of the study suggest that, in children, regeneration of the fibula by implanting beta-tricalcium phosphate into a bone defect can reduce morbidity of the fibula harvest sites. Level of Evidence: Therapeutic study, Level IV (case series—no, or historical control group)