Munehisa Kito

Clinical outcome of deep-seated atypical lipomatous tumor of the extremities with median-term follow-up study

AIMS There is no consensus on the best surgical treatment for deep-seated atypical lipomatous tumor (ALT) of the extremities; furthermore, the appropriate duration for follow-up observation remains unclear. We investigated clinical and functional median-term outcomes in the primary operations for ALT of the extremities in order to find its best treatment methods and observation periods. METHODS From 1996 to 2009, we diagnosed 41 patients with deep-seated ALT of the extremities. Wide resection was performed on 11 patients and marginal resection was performed on 30 patients. The minimum follow-up was 5 years (median, 8.5; range, 5-17.4). Patients were evaluated for their local recurrence, dedifferentiation, and post-operative function using the ISOLS/MSTS scoring system. RESULTS Recurrence and dedifferentiation rates were both 0% for the wide resection group, while the rates were 23% (7/30) and 3% (1/30) for the marginal resection group, respectively. Median duration before recurrence was 7.2 years (range, 4.0-14.2). Local recurrence-free survival rate was significantly higher in the wide resection group (P = 0.013). In the marginal resection group, 10% (3/30) of the cases showed residual tumor. The localization of these tumors was all intermuscular. The ISOLS/MSTS scores were 98% (range, 90-100) for wide resection and 99% (range, 93-100) for marginal resection, with no statistical difference (P = 0.694). No ALT-related deaths occurred during the observation period. CONCLUSIONS In addition to long-term (at least 8 years) of continuous observation, a wide resection is necessary in order to prevent recurrence, dedifferentiation, and residual tumor.

Preoperative radiographic and histopathologic evaluation of central chondrosarcoma

BackgroundDistinguishing grade 1 chondrosarcoma from grade 2 chondrosarcoma is critical both for planning the surgical procedure and for predicting the outcome. We aimed to review the preoperative radiographic and histologic findings, and to evaluate the reliability of preoperative grading.MethodsWe retrospectively reviewed the medical records of 17 patients diagnosed with central chondrosarcoma at our institution between 1996 and 2011. In these cases, we compared the preoperative and postoperative histologic grades, and evaluated the reliability of the preoperative histologic grading. We also assessed the preoperative radiographic findings obtained using plain radiography, computed tomography (CT), and magnetic resonance imaging (MRI).ResultsPreoperative histologic grade was 1 in 12 patients, 2 in 4 patients, and 3 in 1 patient. However, 6 of the 12 cases classified as grade 1 before surgery were re-classified as grade 2 postoperatively. In the radiographic evaluation, grade 1 was suspected by the presence of a ring-and-arc pattern of calcification on plain radiography and CT and entrapped fat and ring-and-arc enhancement on MRI. Grades 2 and 3 were suspected by the absence of calcification and the presence of cortical penetration and endosteal scalloping on plain radiography and CT, as well as soft-tissue mass formation on MRI.ConclusionAlthough the combination of radiographic interpretation and histologic findings may improve the accuracy of preoperative grading in chondrosarcoma, the establishment of a standard evaluation system with the histologic and radiographic findings and/or the development of new biologic markers are necessary for preoperative discrimination of low-grade chondrosarcoma from high-grade chondrosarcoma.

A recurrent solitary fibrous tumor of the thigh with malignant transformation: A case report

Highlights • Solitary fibrous tumors (SFTs) of the extremities are rare.• We report a case of recurrent SFT in the thigh with malignant transformation.• Our current case showed a long-term benign course before the operation.• This tumor displayed a homogeneously high-grade area at recurrence.• Careful consideration is necessary for treating this tumor.

Chondroitin sulfate synthase 1 expression is associated with malignant potential of soft tissue sarcomas with myxoid substance

The glycosyltransferases chondroitin sulfate synthase 1 (CHSY1) and exostoses-like 3 (EXTL3) specifically function in biosynthesis of the glycans chondroitin sulfate and heparan sulfate, respectively. Although these glycans play important roles in pathogenesis of various tumors, their significance in soft tissue sarcoma remains unknown. Here, we asked whether CHSY1 or EXTL3 expression correlates with malignant potential of soft tissue sarcomas with myxoid substance. To do so, we examined 40 samples representing specific types, including 12 cases of myxoid liposarcoma, 14 of myxofibrosarcoma, 12 of malignant peripheral nerve sheath tumor, and 2 of low-grade fibromyxoid sarcoma. We performed immunohistochemistry with anti-CHSY1 and anti-EXTL3 antibodies and compared enzyme expression levels with tumor histologic grade as assessed by the Fédération Nationale des Centres de Lutte Contre le Cancer classification and with patient 5-year survival rate. CHSY1 and EXTL3 were expressed in 72.5% and 32.5% of all tumors, respectively. Notably, CHSY1 was strongly expressed in myxofibrosarcoma and malignant peripheral nerve sheath tumor compared with other tumors and significantly associated with higher- rather than lower-grade tumors (P < .01). High expression of CHSY1 was also significantly associated with poorer patient outcomes (P = .031) and higher stages assessed by American Joint Committee on Cancer staging system (P = .004). By contrast, EXTL3 expression was not correlated with histologic grade or patient prognosis. We conclude that CHSY1 expression is closely associated with malignant potential of soft tissue sarcomas with myxoid substance.

Knee extension strength and post-operative functional prediction in quadriceps resection for soft-tissue sarcoma of the thigh

Objectives Our objective was to predict the knee extension strength and post-operative function in quadriceps resection for soft-tissue sarcoma of the thigh. Methods A total of 18 patients (14 men, four women) underwent total or partial quadriceps resection for soft-tissue sarcoma of the thigh between 2002 and 2014. The number of resected quadriceps was surveyed, knee extension strength was measured with the Biodex isokinetic dynamometer system (affected side/unaffected side) and relationships between these were examined. The Musculoskeletal Tumor Society (MSTS) score, Toronto Extremity Salvage Score (TESS), European Quality of Life-5 Dimensions (EQ-5D) score and the Short Form 8 were used to evaluate post-operative function and examine correlations with extension strength. The cutoff value for extension strength to expect good post-operative function was also calculated using a receiver operating characteristic (ROC) curve and Fisher’s exact test. Results Extension strength decreased when the number of resected quadriceps increased (p < 0.001), and was associated with lower MSTS score, TESS and EQ-5D (p = 0.004, p = 0.005, p = 0.006, respectively). Based on the functional evaluation scales, the cutoff value of extension strength was 56.2%, the equivalent to muscle strength with resection of up to two muscles. Conclusion Good post-operative results can be expected if at least two quadriceps muscles are preserved. Cite this article: A. Tanaka, Y. Yoshimura, K. Aoki, M. Kito, M. Okamoto, S. Suzuki, T. Momose, H. Kato. Knee extension strength and post-operative functional prediction in quadriceps resection for soft-tissue sarcoma of the thigh. Bone Joint Res 2016;5:232–238. DOI: 10.1302/2046-3758.56.2000631.

The status quo of treatment and clinical outcomes for patients over 80 years of age with high-grade soft tissue sarcoma: report from the soft tissue tumor registry in Japan

Objective The purpose of this study is to clarify the status quo of management and clinical outcome of treatments for oldest-old (≥80 years) patients with high-grade soft tissue sarcomas in Japan. Method The present study was conducted using data from the Soft Tissue Tumor Registry in Japan. There were 956 oldest-old patients with soft tissue sarcoma who were registered from 2006 to 2012. Among them, cases with incomplete data, low-grade soft tissue sarcoma and those who underwent treatment at other institutions were excluded from analysis. Results We examined 451 cases of high-grade soft tissue sarcoma in oldest-old patients. Three-hundred fifty-one cases (77.8%) were surgically managed, while 100 cases were conservatively managed. In patients aged 85 years and older, 73.1% underwent surgical treatment. A significantly higher proportion of patients underwent conservative therapy in oldest-old patients aged 85 years or older (P = 0.036), patients with deep-seated tumors (P = 0.027) and patients with distant metastases at the first visit (P = 0.000). The median follow-up period was 18.9 months (range, 0.2-83.1). Risk factors for overall survival were extracompartmental tumor progression (P = 0.014) and presence of distant metastases at the first visit (P = 0.000). Conclusion We reported the status quo of treatment and clinical outcome for oldest-old patients with high-grade soft tissue sarcoma in Japan. Although surgery is the primary treatment for soft tissue sarcoma, a significantly higher proportion of patients underwent conservative therapy over surgical treatment in patients aged 85 years or older, patients with deep-seated tumors and patients with distant metastases.

Incidence, Diagnosis, and Risk Factors of Venous Thromboembolism after Surgery for Malignant Bone and Soft Tissue Tumor of Lower Extremity

Objective: This study aimed to prospectively evaluate the incidence, characteristics, and risk factors of venous thromboembolism (VTE) development, and the diagnostic value of blood coagulation markers in patients receiving surgery for malignant bone and soft tissue tumor of lower extremity. Methods: A prospective study of 20 patients who were examined using ultrasonography. Serum soluble fibrin monomer complex (SFMC) and D-dimer were measured in the perioperative period. VTE incidence, VTE development time, change in blood coagulation markers, and effect of each risk factor were evaluated. Results: VTE was found in 8 of 20 patients. Four of these 8 patients had the finding of pulmonary embolism (PE) without symptom. Onset time of VTE was from day 1 to 7 after surgery. The cutoff value of SFMC was <3 μg/mL at any measurement point and D-dimer was approximately 2 g/mL in receiver operating characteristic analysis. Body mass index was the only significant risk factor. Conclusion: VTE showed high incidence and often occurred in the early period in only physical prophylaxis after surgery. SFMC or D-dimer was not always useful to detect VTE development. With regard to rehabilitation intervention, risk management is required until 1 week after surgery.

Prediction of muscle strength and postoperative function after knee flexor muscle resection for soft tissue sarcoma of the lower limbs

INTRODUCTION Oncological margins and prognosis are the most important factors for operative planning of soft tissue sarcomas, but prediction of postoperative function is also necessary. The purpose of this study was to predict the knee flexion strength and postoperative function after knee flexor muscle resection for soft tissue sarcoma of the lower limbs. MATERIALS AND METHODS Seventeen patients underwent knee flexor muscle resection for soft tissue sarcoma of the lower limbs between 1991 and 2015. The type of resected muscles was surveyed, knee flexion strength (ratio of affected to unaffected side) was evaluated using the Biodex System isokinetic dynamometer, and differences between the type of resected muscles were examined. The Musculoskeletal Tumor Society (MSTS) score, Toronto Extremity Salvage Score (TESS), European Quality of Life-5 Dimensions (EQ-5D), and Short Form 8 (SF-8) were used to assess postoperative function and examine correlations with flexion strength. The cutoff value for flexion strength to predict good postoperative results was calculated by a receiver operating characteristic (ROC) curve and Fishers exact test. RESULTS Median flexion strength decreased in the resection of sartorius (97.8%), gracilis (95.4%), gastrocnemius (85.2%; interquartile range (IQR): 85.0-86.2), medial hamstrings (semimembranosus and semitendinosus, 76.2%; IQR: 73.3-78.0), lateral hamstrings (long and short head of biceps femoris, 66.1%; IQR: 65.9-70.4), and bilateral hamstrings (27.3%; IQR: 26.6-31.5). A significant difference was observed between lateral and bilateral hamstrings resection (P=0.049). Flexion strength was associated with lower functional scales (MSTS score, P=0.021; TESS, P=0.008; EQ-5D, P=0.034). Satisfactory function was obtained at a flexion strength cutoff value of 65.7%, and strength remained above the cutoff value up to unilateral hamstrings resection. DISCUSSION Greater knee flexor muscles resection can result in functional deficits that are associated with decreased flexion strength. If continuity of unilateral hamstrings is maintained, good postoperative results can be expected. LEVEL OF EVIDENCE IV, retrospective study.

Locked Metacarpophalangeal Joint of the Middle Finger Caused by a Lipoma in the Flexor Tenosynovium

The locking of the metacarpophalangeal (MCP) joint of a finger is a common entity that is characterized by a loss of active and passive extension of the MCP joint with normal mobility of the proximal interphalangeal (PIP) and distal interphalangeal (DIP) joints. This disorder should be distinguished from “trigger finger,” which occurs much more frequently. The locked MCP joint mostly occurs with sudden onset in the index or middle finger in adults or the elderly1. Locking often is caused by the collateral or accessory collateral ligament that catches on the prominent radial condyle of the metacarpal head or osteophytes on the volar metacarpal head1. Other reported causes are irregularities of the articular surfaces of the MCP joint, tears of the collateral ligaments or palmar plate, an intra-articular loose body, and sesamoid entrapment2. We report a case of a locked MCP joint that was caused by a lipoma in the flexor tenosynovium of the middle finger. The patient was informed that data concerning the case would be submitted for publication, and she provided consent. Over a two-year period, a sixty-two-year-old woman had experienced an extension lag at the MCP joint of the right middle finger without evidence of a particular cause. She denied any prior experiences of the snapping phenomenon in the involved digit. Although passive extension initially had been possible, the patient had developed painful triggering at the MCP joint and eventually had difficulty with writing and keyboard use. Subsequently, she had noticed a soft and painless tumor on the right palm. Upon initial presentation to our institution, there had been no change in …

Intraosseous neurilemmoma of the proximal ulna

INTRODUCTION Neurilemmoma is a benign nerve sheath neoplasm commonly located in the soft tissue. Intraosseous neurilemmoma is rare, constituting less than 1% of primary bone tumors. PRESENTATION OF CASE A 21 year-old woman was presented with left elbow pain of 1-month duration. Plain radiographs showed a well-defined, lytic and expansile lesion of the proximal ulna. Computed tomography revealed cortical destruction and soft tissue extension. Because the tissue of origin for the tumor was uncertain, an open biopsy was performed. The specimens demonstrated a benign spindle cell tumor suggestive of a neurilemmoma, similar to a soft tissue neurilemmoma. The diagnosis of intraosseous neurilemmoma was established. Marginal excision of the soft tissue component and curettage of the lesion in the bone were performed. After 3.5 years of follow up, there is no clinical or radiographic finding to suggest any recurrence. DISCUSSION The major site of intraosseous neurilemmoma is the mandible. Occurrence in the long bone is particularly rare. Only two cases of intraosseous neurilemmoma involving the bones around the elbow have been reported to our knowledge; these cases arose in the distal humerus. We describe the first case of intraosseous neurilemmoma of the proximal ulna of the left elbow. The recommended treatment is conservative resection and bone grafting, as malignant change is extremely rare. CONCLUSION Although very rare, intraosseous neurilemmoma should be taken under consideration in the differential diagnosis of painful, radiographically benign-appearing osseous tumor around the elbow.