Muscle strength and functional recovery for soft-tissue sarcoma of the thigh: a prospective study.

BACKGROUND: This study aimed to investigate changes in muscle strength and functional outcome before and after surgery for soft-tissue sarcoma of the thigh and to examine the timing of recovery. METHODS: From 2014 to 2019, 15 patients who underwent multiple resections of the thigh muscle for soft-tissue sarcoma of the thigh were included in this study. The muscle strength was measured with an isokinetic dynamometer for the knee joint and with a hand-held dynamometer for the hip joint. The functional outcome assessment was based on the Musculoskeletal Tumor Society (MSTS) score, Toronto Extremity Salvage Score (TESS), European Quality of Life-5 Dimensions (EQ-5D), and maximum walking speed (MWS). All measurements were conducted preoperatively and at 3, 6, 12, 18, and 24 months postoperatively, and the ratio of postoperative to preoperative value was used. A repeated-measures analysis of variance was performed to compare changes over time and to investigate the recovery plateau. Correlations between changes in muscle strength and functional outcomes were also examined. RESULTS: The muscle strength of the affected limb, MSTS score, TESS, EQ-5D, and MWS were significantly decreased at 3 months postoperatively. The recovery plateau was subsequently reached at 12 months postoperatively. The changes in muscle strength of the affected limb and functional outcome showed a significant correlation. CONCLUSIONS: The estimated postoperative recovery for soft-tissue sarcoma of the thigh is 12 months after surgery.

Influence of the adductor compartment resection on muscle strength and postoperative function in soft-tissue sarcoma of the thigh.

OBJECTIVE: To predict the muscle strength and postoperative function for soft-tissue sarcoma arising from the adductor compartment of the thigh. METHODS: Between 2003 and 2019, 17 cases that underwent resection of the adductor muscle group (adductor longus, adductor magnus, adductor brevis, gracilis and pectineus) for soft-tissue sarcoma in the adductor compartment of the thigh were included. The muscle strength was measured with an isokinetic dynamometer for the knee joint and with a hand-held dynamometer for the hip joint (ratio of affected to unaffected side). The Musculoskeletal Tumor Society score, Toronto Extremity Salvage Score, European Quality of Life-5 Dimensions and maximum walking speed were used to assess postoperative function and examine correlations with muscle strength. RESULTS: In 13 cases that underwent an isolated resection of the adductor compartment, reduced adduction strength correlated with increased number of resected muscles in the adductor muscle group (P < 0.001). Postoperative function was maintained, showing no correlations with adduction strength. In four cases that underwent combined resections of other compartments, a decrease was observed in adduction strength as well as the muscle strength of other resected muscles, in addition to a decline in postoperative function. In the 4 or 5 adductor muscle resection group, the comparison between isolated and combined resection revealed comparable results for adduction strength but a significant decrease in postoperative function for the combined resection group. CONCLUSIONS: Postoperative function can be preserved for isolated adductor compartment resection. Combined resections of multiple muscles in other compartments and most adductor muscles may result in decreased postoperative function.

Points of consideration when performing surgical procedures for proximal femoral bone metastasis.

BACKGROUND: To assess the points of consideration when performing surgical procedures for proximal femoral bone metastasis. METHODS: Fourty patients who underwent surgery for proximal femoral bone metastasis from 2009 to 2019 were included. Prognostic assessments were performed based on the Katagiri scoring system. The low-risk group underwent endoprosthetic replacement (EPR) following resection, while the high-risk group underwent internal fixation (IF). For the intermediate-risk group, one of the surgical procedures was chosen depending on general and local condition. Survival period, walking ability, and treatment failure were evaluated. RESULTS: Sixteen and 24 patients underwent EPR and IF, respectively. Although walking reacquisition rate was 94% (15 of 16 patients) for EPR and 75% (18 of 24 patients) for IF (p = 0.210), the median time to walking was shorter in IF compared to EPR (EPR, 29 days, interquartile range [IQR] 23-40; IF, 14 days, IQR 9-24; p = 0.014). Neither EPR nor IF resulted in treatment failure for those with survival periods of <1 year. The treatment failure rate for those with survival periods of ≥1 year was significantly different between EPR (9%, 1 of 11 patients) and IF (50%, 5 of 10 patients) (p = 0.038). All five patients of treatment failure for IF were renal cancer with no bone formation in the intermediate-risk group. Of the 13 patients who underwent IF for the intermediate-risk group, treatment failure did not occur in 5 patients with bone formation. CONCLUSIONS: Although EPR is a more reliable treatment than IF, patients with life expectancy of <1 year are sufficiently manageable with IF. For the intermediate-risk group, EPR should be selected for cases without expected bone formation, and IF can be considered for cases with expected bone formation due to the risk of treatment failure for IF at ≥ 1 year after surgery.

Risk factor for wound complications following wide resection of soft tissue sarcoma in the adductor compartment of the thigh.

BACKGROUND: The purpose of this study was to investigate deep-seated soft tissue sarcoma (STS) occurring in the adductor compartment of the thigh that underwent wide resection and to clarify the high-risk group for wound complications. PATIENTS AND METHODS: From 2000 to 2017, we reviewed 104 cases of deep-seated STS occurring in the adductor compartment of the thigh that were treated at four specialized facilities with expertise in sarcoma treatment. RESULTS: Wound complications occurred in 40 cases (38.5%), of which 23 cases (22.1%) were cases with major wound complications (MWC). In univariate analysis, BMI (P < 0.01), maximum tumor diameter (P < 0.01), operation time (P < 0.01), amount of intraoperative bleeding (P < 0.01), and intraoperative intervention to the femoral artery and vein (P < 0.01) were significantly associated with wound complications. In multivariate analysis, the associated parameters were BMI (P < 0.01), maximum tumor diameter (P = 0.02), and intraoperative intervention to the femoral artery and vein (P = 0.01). When limited to cases with MWC, univariate analysis showed that maximum tumor diameter (P < 0.01), diabetes mellitus (P = 0.03), operation time (P < 0.01), amount of intraoperative bleeding (P < 0.01), and intraoperative intervention to the femoral artery and vein (P = 0.02) were significantly associated parameters. In multivariate analysis, maximum tumor diameter (P = 0.02) and amount of intraoperative bleeding (P = 0.04) were associated parameters. CONCLUSIONS: For patients with risk factors for wound complications, control of bleeding are crucial when resecting deep-seated STS in the adductor compartment of the thigh. In cases with large tumors, surgeons should be especially cautious of cases requiring interventions that surround the femoral artery and vein in order to attain an appropriate surgical margin.

Relationship of Malnutrition During Hospitalization With Functional Recovery and Postdischarge Destination in Elderly Stroke Patients.

AIM: Malnutrition during hospitalization affects the functional recovery and postdischarge destinations of elderly stroke patients. However, insufficient studies exist about nutritional status during hospitalization in the acute stroke phase in this population. This study determined factors of nutritional status changes during hospitalization in elderly patients in the acute phase of stroke, and investigated the relationship between nutritional status changes and improved activities of daily living and postdischarge destination. METHODS: This retrospective observational study included 205 acute-phase stroke patients admitted to Shinshu University Hospital from 2010-2016. Multiple regression analysis was conducted to determine relationships between nutritional status changes, patient characteristics, and improved activities of daily living. Binomial logistic regression analysis was used to determine the relationship between the postdischarge destination and nutritional status changes. RESULTS: Prevalence of malnutrition was 42% at admission and 76% at discharge. Factors affecting nutritional status changes at admission included Geriatric Nutritional Risk Index (ß = -0.35, P < .001) and Barthel Index/feeding (ß = 0.22, P = .002), and factors during hospitalization included age (ß = -0.21, P < .001), ischemic stroke (ß = 0.16, P = .008), and National Institute of Health Stroke Scale score (ß = -0.29, P < .001). Significant associations of changes in geriatric nutritional risk index occurred with improved activities of daily living during hospitalization (ß = 0.26, P < .001) and discharge to home (odds ratio = 1.11, 95% confidence interval: 1.03-1.19, P = .008). CONCLUSION: Many elderly patients in the acute phase of stroke with malnutrition exhibited worsening conditions during hospitalization, which was negatively associated with their activities of daily living abilities and postdischarge destinations. Nutritional status changes and associated factors must be evaluated during hospitalization in this patient population.

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.

Initial clinical presentation of single soft tissue metastasis of medullary thyroid carcinoma without primary tumor in the thyroid gland.

BACKGROUND: Single soft tissue metastasis of medullary thyroid carcinoma is extremely rare. In addition, several occult medullary thyroid carcinomas with distant metastasis were reported, but undetectable primary lesion at diagnosis was also extremely rare. CASE PRESENTATION: A 74-year-old man was admitted to our hospital because of a painful nodule in his left buttock for over 1 year. Needle biopsy was performed, and the histological findings revealed adenocarcinoma positive for thyroid transcription factor-1. No evidence of a primary tumor, including the lung and thyroid gland, could be found elsewhere despite detailed examinations, including thyroid echography, chest computed tomography, and fluorodeoxyglucose-positron emission tomography. The soft tissue tumor was resected with a wide margin. Immunohistochemical analysis showed the tumor cells to be positive for cytokeratin-AE1/3, cytokeratin 7, synaptophysin, chromogranin A, calcitonin, and carcinoembryonic antigen, but negative for cytokeratin 20, Napsin A, Pax8, and p40, resulting in a diagnosis of metastasis of medullary thyroid carcinoma. CONCLUSION: Initial presentation with a single metastasis to soft tissue and undetectable primary tumor in the thyroid gland is an extremely rare clinical manifestation in patients with medullary thyroid carcinoma.

Clinical outcomes of patients 80 years of age and older with soft tissue sarcoma.

OBJECTIVES: Although soft tissue sarcoma (STS) is rare, its incidence is increasing among older patients. Few studies have compared the outcomes between conservative and surgical treatments for STS patients aged ≥80 years. We assessed the outcomes of both treatments in this population and the association between older age and surgical outcome. METHODS: We recruited consecutive patients with STS aged ≥80 years treated at our institution between January 2006 and May 2014. We recommended surgical resection for all patients without multiple distant metastases. Overall survival and sarcoma-specific survival were assessed using the Kaplan-Meier method. RESULTS: Of the 39 patients with STS who presented at our institution, 37 were included in this analysis (19 men and 18 women with a median age of 85 [range 80-94] years). Tumors were classified as Stage IB (n = 3), IIA (n = 6), IIB (n = 3) or III (n = 24). Four patients underwent conservative therapy and 33 underwent surgical resection. The most common tumor site was the lower extremity, and the majority of tumors were classified as undifferentiated pleomorphic sarcoma. The follow-up rate was 100%. One-year sarcoma-specific survival rates were 25.0% in the conservative therapy group and 90.9% in the surgical resection group. No associations were found between age ≥85 years and perioperative complications or clinical outcome. CONCLUSIONS: Surgical resection had relatively few complications, given the age group, and improved the prognosis of older patients with STS. Surgical resection of STS with curative intent should be considered in older patients.

Clinical outcome of dedifferentiated liposarcoma in the extremities: A retrospective case series of 7 patients.

BACKGROUND: Wide resection is the generally recommended surgical treatment for dedifferentiated liposarcoma (DDLPS) in the extremities. However, it may be appropriate to distinguish the surgical margin of low-grade atypical lipomatous tumor (ALT)/well-differentiated liposarcoma (WDLPS) area from the high-grade dedifferentiated area, because the low- and high-grade areas can be clearly separated, both radiologically and histologically. This study re-evaluated the details of surgical margin of DDLPS in the extremities, and aimed to investigate the optimal surgical margin and the usefulness of adjuvant therapy for DDLPS in the extremities. METHODS: Seven patients diagnosed with DDLPS in the extremities and treated between 1995 and 2013 were analyzed. The use of adjuvant therapy before and after surgery was assessed, and the surgical margins for the ALT/WDLPS and dedifferentiated areas were re-evaluated by using the specimens resected at surgery. Subsequently, the recurrence rates, metastatic rates, and oncological outcomes were examined. RESULTS: Four and three patients had wide (adequate wide margin, n = 3; inadequate wide margin, n = 1) and marginal margins for the dedifferentiated area, respectively, while three and four patients had wide (adequate wide margin, n = 2; inadequate wide margin, n = 1) and marginal margins for the ALT/WDLPS area, respectively. Postoperative radiotherapy was performed in three patients with an inadequate wide margin or a marginal margin for the dedifferentiated area. No patient had local recurrence. Distant metastases occurred in two patients. These patients died of their disease. The other five patients were disease-free. CONCLUSION: The ALT/WDLPS and dedifferentiated areas in the tumor margin may be better to be considered separately in determining the appropriate resection extent for DDLPS in the extremities. Postoperative radiotherapy may provide good local control for cases with a narrow surgical margin.

Preoperative radiographic and histopathologic evaluation of central chondrosarcoma.

BACKGROUND: Distinguishing 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. METHODS: We 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). RESULTS: Preoperative 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. CONCLUSION: Although 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.

The usefulness of immunohistochemistry for phosphohistone H3 as a prognostic factor in myxoid liposarcoma.

Myxoid liposarcoma (MLS) is a common subtype of liposarcoma. Although the prognosis is generally good, there are factors known to be associated with poor prognosis. Accurate indices are important to predict prognosis. We aimed to assess the usefulness of immunohistochemistry for phosphohistone H3 (PHH3) as a potential biomarker in comparison with Ki-67 antigen and other prognostic factors. Twenty-five patients with MLS were evaluated. Age, sex, depth of tumor, tumor size, surgical margin, oncological outcome, histological grade, presence of necrosis, proportion of round cell component (RC%), PHH3 index, and Ki-67 index were examined. Prognostic factors of the examination criteria were statistically analyzed, survival rate analyses were performed using the Kaplan-Meier method, and multivariate analysis was performed using Cox proportional-hazard regression analysis. The number of PHH3-positive tumor cells and the PHH3 and Ki-67 indices demonstrated a statistical correlation with the prognosis of MLS in univariate analysis (P < 0.001, P < 0.001, P = 0.01, respectively). PHH3 index and RC% were significant factors in multivariate analysis (P = 0.03, P = 0.02). The immunohistochemistry of PHH3 may be associated with prognosis and could serve as a valid criterion of histological grade in MLS.

Metastatic carcinoma to subcutaneous tissue and skeletal muscle: clinicopathological features in 11 cases.

OBJECTIVE: Metastatic carcinoma to subcutaneous tissue or skeletal muscle is relatively rare. The present study aimed to clarify the clinicopathological features for confirming the diagnosis as soft tissue metastasis and determining the primary site. METHODS: We reviewed records of 11 patients with soft tissue metastasis who were in our institution from 1996 to 2009. RESULTS: In 9 of 10 patients who underwent magnetic resonance imaging, findings consisted of poorly circumscribed high-intensity lesions around the tumor on T2-weighted images, irregular peritumoral enhancement and poorly enhanced lesions at the center of the tumor on T1-weighted images. Systematic immunohistochemical examination was more valuable for diagnosing as soft tissue metastasis and confirming the primary site. The expression patterns of cytokeratins 7 and 20 and tissue-specific antibodies such as thyroid transcription factor-1, MUC5AC and CDX2 were useful diagnostic markers. The primary site could be determined in five patients with cytokeratin 7/20 immunophenotype and positivity for tissue-specific antibodies. In four cases, determination of the primary site finally became possible by comparison with the histological findings of operative specimens in past carcinoma and/or in consideration of radiological findings and the results of cytokeratin 7/20 phenotyping. CONCLUSIONS: Systematic immunohistochemical examination is helpful for confirmation of the primary origin in soft tissue metastasis of carcinoma in addition to clinical information such as the history and condition of past carcinoma, radiological findings and comparison between the histology of biopsy specimens and past carcinoma.

Anatomic double-bundle anterior cruciate ligament reconstruction, using CT-based navigation and fiducial markers.

PURPOSE: Accurate placement of separate anteromedial and posterolateral bundle bone tunnels is crucial for anatomic, double-bundle anterior cruciate ligament (ACL) reconstruction. However, identifying the anatomic footprint at which to make the tibial and femoral bone tunnels is not a straightforward procedure. To overcome this problem, we used a CT-based navigation technique with a registration procedure based on fiducial markers (FMs). METHODS: Preoperatively, 10 FM points were placed on skin around knee joint and scanned with CT. Imaging data of the knee were recorded on the computer system for preoperative registration and surgical planning. Intraoperatively, with a reference frame fixed to the distal medial aspect of femur and tibia, paired-point matching registration was performed with the use of points marked on skin through FM center holes. During tibial tunnel guide wire placement, tibial aiming guide with tracking device fed back the position of tip and direction of the guide wire on the three-dimensional (3D) tibia bone surface image and multiple image planes in real time. For the femoral side, the navigation pointer was placed at the footprint center with visual guidance of 3D image of lateral wall sagittal view on navigation monitor and marked with navigation awl. RESULTS: The average registration accuracy of 22 consecutive patients was 0.7 ± 0.2 mm and 0.6 ± 0.2 mm for femoral and tibial bone, respectively. Most of the bone tunnel positions evaluated with 3D-CT image were confirmed to be accurately placed in reference to the preoperative plan. There was no damage to femoral condyle cartilage and no other complication. CONCLUSION: This new CT-based computer navigation system opens the possibility for surgeons to plan bone tunnel positioning preoperatively and control it during technically demanding anatomic double-bundle ACL reconstruction.

Multifocal periosteal chondromas in the ring finger of an adolescent boy: case report.

We describe an unusual case of a 12-year-old boy who presented with a loss of motion in the ring finger caused by 2 separate periosteal chondromas involving the proximal and middle phalanges. Range of motion improved and recurrence did not occur at the 5-year follow-up after marginal excision of both lesions.

Distal femoral impaction bone grafting in revision for tumor endoprosthesis.

BACKGROUND: Reconstruction using tumor endoprosthesis has been widely used in cases with large bone defects caused by bone and soft tissue tumor resection of the distal femur which extend into the knee joint. However, reconstruction failure can lead to major problems in the long term. We have been performing impaction bone grafting with allogeneic cancellous bone during revision surgery for tumor endoprosthesis of the distal femur to compensate for the thinness and fragility of the remaining femur. The aim of this study is to examine the surgical method, problems, and clinical outcomes of revision surgery with impaction bone grafting. METHODS: Three patients who underwent revision surgery for tumor endoprosthesis using impaction bone grafting at our institution with more than 2 years of follow-up were included. RESULTS: Union between the graft and host bone were achieved in all cases. The mean time to radiographic union was 1.0 year (0.6-1.5 years). Although intraoperative penetration to the anterior cortex of the distal femur occurred in 2 cases, there were no postoperative fractures. There were no failures of tumor endoprosthesis at final observation. CONCLUSION: Good short-term results were observed in 3 patients who underwent revision tumor endoprosthesis with impaction bone grafting following a bone and soft tissue tumor resection of the distal femur. The method was considered to be a useful treatment option. Impaction bone grafting is an established surgical option that can be applied to revision surgery for tumor endoprosthesis.

Antitumor Effect of Sclerostin against Osteosarcoma.

Various risk factors and causative genes of osteosarcoma have been reported in the literature; however, its etiology remains largely unknown. Bone formation is a shared phenomenon in all types of osteosarcomas, and sclerostin is an extracellular soluble factor secreted by osteocytes that prevents bone formation by inhibiting the Wnt signaling pathway. We aimed to investigate the antitumor effect of sclerostin against osteosarcoma. Osteosarcoma model mice were prepared by transplantation into the dorsal region of C3H/He and BALB/c-nu/nu mice using osteosarcoma cell lines LM8 (murine) and 143B (human), respectively. Cell proliferations were evaluated by using alamarBlue and scratch assays. The migratory ability of the cells was evaluated using a migration assay. Sclerostin was injected intraperitoneally for 7 days to examine the suppression of tumor size and extension of survival. The administration of sclerostin to osteosarcoma cells significantly inhibited the growth and migratory ability of osteosarcoma cells. Kaplan-Meier curves and survival data demonstrated that sclerostin significantly inhibited tumor growth and improved survival. Sclerostin suppressed the proliferative capacity and migratory ability of osteosarcoma cells. Osteosarcoma model mice inhibited tumor growth and prolonged survival periods by the administration of sclerostin. The effect of existing anticancer drugs such as doxorubicin should be investigated for future clinical applications.

Continued growth of locally aggressive fibrous dysplasia of 22 years duration after reaching adulthood: a case report.

Fibrous dysplasia generally stops growing when patients reach adulthood. Locally aggressive fibrous dysplasia is an extremely rare subtype of fibrous dysplasia that is characterized by progressive enlargement after bone maturation, cortical bone destruction and soft tissue invasion but without malignant transformation. At 50 years of age, a tumor was found in the rib of a patient. The tumor gradually enlarged over time and imaging findings suggested a malignant tumor. The case was further complicated by restrictive lung disorder. Biopsies from multiple sites showed no malignant findings, and marginal resection with partial curettage was performed. The final diagnosis was locally aggressive fibrous dysplasia, and the restrictive lung disorder improved postoperatively. The natural history of the disease is also unknown. This is the first report in the literature to describe a case in which a lesion exhibited long-term growth over a period of 22 years after reaching adulthood.

Serum soluble interleukin-2 receptor levels in patients with malignant lymphoma of bone.

BACKGROUND: The reliability of selected serum markers and radiological features for distinguishing malignant lymphoma of the bone from other osteolytic bone lesions was examined in an effort to improve the differential diagnosis. METHODS: A total of 23 patients with histologically verified malignant lymphoma of the bone, 57 patients with other osteolytic malignancies (35 males, 22 females; mean age 62.8 years, range 13-89 years), and 13 patients with benign bone lesions that resemble malignant tumor radiographically (6 men, 7 women; mean age 48.1 years, range 20-73 years) were retrospectively reviewed. We evaluated the serum levels of soluble interleukin-2 receptor (sIL-2R), lactate dehydrogenase, and C-reactive protein in addition to radiographic examination and gallium-67 scanning. RESULTS: Although every clinical feature examined was found to show significant differences between lymphoma and the other two groups, the feature most highly suggestive of malignant lymphoma is a high serum sIL-2R level (sensitivity 0.95, specificity 0.70, accuracy 0.81). CONCLUSIONS: The serum sIL-2R level can be a valuable marker for diagnosing malignant lymphoma of the bone.