Background Limited data exist on the optimal postoperative surveillance protocol for high-grade soft tissue sarcoma, particularly regarding the optimal imaging modality and imaging interval for detecting local recurrence. This study aimed to assess the benefit of short-term postoperative ultrasonography (USG) for detecting local recurrence in patients with high-grade soft tissue sarcoma. Methods Patients with newly diagnosed high-grade soft tissue sarcoma who underwent surgical resection between January 2010 and June 2020 were included. Short-term USG was added to the follow-up protocol as a surveillance tool alongside routine magnetic resonance imaging (MRI). The primary outcome was the additional detection rate of short-term USG compared with routine MRI surveillance for early local recurrence detection. Subgroup analysis was performed to evaluate factors influencing USG detection rate. The additional detection rate of short-term USG for detection of metastatic lymph nodes was also evaluated. The secondary outcome was the false referral rate of short-term USG. Results In total, 198 patients (mean age ± standard deviation: 52.1 ± 15.8 years; 94 women) were included. Local recurrence occurred in 20 patients (10.1%; 20/198). Short-term USG detected local recurrence in advance of routine MRI visits in 7 out of 198 patients, resulting in an additional detection rate of 3.5% (95% CI: 1.7–7.1%). Subgroup analysis showed no significant difference in the short-term USG detection rate based on initial tumor characteristics, and receipt of radiotherapy or chemotherapy. Short-term USG additionally detected five of seven patients with metastatic lymph nodes [2.5% (95% CI, 1.1–5.8%, 5/198)]. The false referral rate of short-term USG was 3.5% (95% CI: 1.7–7.1%; 7/198). Conclusions Short-term USG as part of postoperative surveillance for high-grade soft tissue sarcoma can enhance early detection of local tumor recurrence and metastatic lymphadenopathy. Early detection of local tumor recurrence could lead to a prompt surgical resection and aid in local disease control.

AIMS:This study aimed to analyze the accuracy and errors associated with 3D-printed, patient-specific resection guides (3DP-PSRGs) used for bone tumour resection. METHODS:We retrospectively reviewed 29 bone tumour resections that used 3DP-PSRGs based on 3D CT and 3D MRI. We evaluated the resection amount errors and resection margin errors relative to the preoperative plans. Guide-fitting errors and guide distortion were evaluated intraoperatively and one month postoperatively, respectively. We categorized each of these error types into three grades (grade 1, < 1 mm; grade 2, 1 to 3 mm; and grade 3, > 3 mm) to evaluate the overall accuracy. RESULTS:The maximum resection amount error was 2 mm. Out of 29 resection amount errors, 15 (51.7%) were grade 1 errors and 14 (38.3%) were grade 2 errors. Complex resections were associated with higher-grade resection amount errors (p < 0.001). The actual resection margins correlated significantly with the planned margins; however, there were some discrepancies. The maximum guide-fitting error was 3 mm. There were 22 (75.9%), five (17.2%), and two (6.9%) grade 1, 2, and 3 guide-fitting errors, respectively. There was no significant association between complex resection and fitting error grades. The guide distortion after one month in all patients was rated as grade 1. CONCLUSION:In terms of the accurate resection amount according to the preoperative planning, 3DP-PSRGs can be a viable option for bone tumour resection. However, 3DP-PSRG use may be associated with resection margin length discrepancies relative to the planned margins. Such discrepancies should be considered when determining surgical margins. Therefore, a thorough evaluation of the preoperative imaging and surgical planning is still required, even if 3DP-PSRGs are to be used.Cite this article: Bone Joint J 2023;105-B(2):190-197.

Purpose For liposarcoma (LPS), clinical course and proper treatment strategies have not been well-established. Recently, immunecheckpoint inhibitors have shown potential efficacy in LPS. We aimed to describe the clinical course of LPS and evaluate the clinical impact of programmed death-ligand 1 (PD-L1). Materials and Methods We reviewed all consecutive patients (n=332) who underwent curative-intent surgery for localized LPS at Asan Medical Center between 1989 and 2017. PD-L1 testing was performed in well-differentiated and dedifferentiated LPS. Results The median age was 56 years with males comprising 60.8%. Abdomen-pelvis (47.6%) and well-differentiated (37.7%) were the most frequent primary site and histologic subtype, respectively. During a median follow-up of 81.2 months, recurrence was observed in 135 (40.7%), and 86.7% (117/135) were loco-regional. Well-differentiated subtype (hazard ratio [HR], 0.38), abdomenpelvis origin (HR, 2.43), tumor size larger than 5 cm (HR, 1.83), positive resection margin (HR, 2.58), and postoperative radiotherapy (HR, 0.36) were significantly related with recurrence-free survival as well as visceral involvement (HR, 1.84) and multifocality (HR, 3.79) in abdomen-pelvis LPS. PD-L1 was positive in 31.5% (23/73) and 51.3% (39/76) of well-differentiated and dedifferentiated LPS, respectively, but had no impact on survival outcomes. Conclusion Clinical course of LPS was heterogeneous according to histology and anatomic location. Clear resection margin was important to lower recurrence and postoperative radiotherapy might have additional benefit. A decent portion of well-differentiated and dedifferentiated LPS were positive for PD-L1, but its prognostic role was unclear. Further research is needed to determine clinical implications of PD-L1, especially for advanced-stage LPS with unmet needs for effective systemic treatment.

Purpose: Because of the heterogeneity of sarcomas, establishing a well-collected, sarcoma specific database is important for sarcoma research. We analyzed the first histology-based, sarcoma-specific institutional registry in Korea, which collected 28 years of patient data according to a predefined data format. Patients and Methods: Adult bone and soft tissue sarcoma patients who were treated from June 1989 to January 2017 were identified and analyzed, based on the ICD-O-3 codes. Results: Among the 3420 patients included, soft tissue and bone sarcomas comprised 77.8% (n = 2661) and 22.2% (n = 759), respectively. Median age at diagnosis was 50 (range, 16-98) in soft tissue sarcomas and 37 (range, 16-85) in bone sarcomas. Males and females comprised 45.5% and 54.5% of soft tissue sarcomas and 52.7% and 47.3% of bone sarcomas, respectively. Among the 3407 patients with treatment data available, 90.5% of the patients with soft tissue sarcomas and 80.8% of the patients with bone sarcomas received surgery first, of which 57.8% and 71.7% did not receive any subsequent treatment, respectively. Overall, the proportion of patients who received surgery alone decreased from 85.7% to 60.5% from the pre-2000 period to the 2010-2017 period. However, the use of adjuvant chemotherapy increased in patients with soft tissue sarcomas (from 8.0% to 17.2% in the same period), and the use of perioperative radiotherapy also increased in both groups (from 1.4% to 22.7% in soft tissue sarcomas, and 0% to 14.5% in bone sarcomas in the same period). In both soft tissue and bone sarcomas, old age (>= 65 years) and diagnosis in the early study period were associated with poorer survival. Conclusion: We presented a comprehensive summary of our sarcoma registry, including the demographics, changes in treatment patterns, and survival outcomes. This study will provide a framework for future studies.

Background/Aim: To compare absolute volume (AV) assessment according to Response Evaluation Criteria in Solid Tumors (RECIST) for the response evaluation of desmoid tumors (DTs) treated with radiotherapy. Patients and Methods: Eighteen patients with DTs ≥3 cm in size were included. Results: The median follow-up duration was 78.0 months. Five patients achieved a complete response according to RECIST, seven reached a partial response (PR), and one eventually exhibited progression. The overall response rate was 61%, the median time to PR was 8.0 months. Six patients achieved stable disease, although three developed progressions. Of the six patients with a PR, the median change in maximum diameter was −46%, and the median change in maximum volume was −84%. Three patients could have been diagnosed with progression at least 6 months earlier if the AV increment was considered. Conclusion: An AV assessment is essential for an accurate response assessment of DTs and radiotherapy seems feasible as a first-line treatment for DTs.

Introduction: Little is known about undifferentiated pleomorphic sarcoma (UPS) because of the low incidence and heterogeneous diagnosis of sarcoma. We investigated the oncologic outcomes of patients with UPS in a real-practice setting in association with adjuvant treatments and assessment of PD-L1 expression. Materials and methods: We retrospectively reviewed consecutive patients who were diagnosed with UPS in Asan Medical Center between January 1995 and December 2016. PD-L1 staining was performed using formalin-fixed paraffin-embedded tumour tissue by immunohistochemistry, and positive PD-L1 expression was defined as staining in >= 1% of tumour cells. The PD-L1 H-score, which was calculated for statistical analysis as intensity (0-3) multiplied by proportion (0-100), ranged from 0 to 300. Results: Of 205 patients included in our analysis, 176 underwent a curative-intent operation for localised disease. The five-year disease-free survival (DFS) rate of resected UPS patients was 54.3%. Administration of adjuvant therapy did not overcome the poor prognostic factors such as primary tumour size (>5 cm) and locations, especially the abdomen and pelvis. The PD-L1 analysis was available for 114 patients, and 83 (72.8%) showed immunoreactivity for PD-L1 with weak (44/83), intermediate (29/83), and strong (10/83) staining intensities. The positive PD-L1 expression seemed to be associated with prolonged DFS, though no statistical significance was observed. Conclusion: Complete surgical resection was the most important UPS treatment strategy, and adjuvant radio- or chemotherapy was insufficient to improve survival. Our results raise the possibility that immunotherapy could be a breakthrough in the treatment of UPS patients. (C) 2020 Elsevier Ltd, BASO - The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.

Pathological femoral fracture (PFF) after radiation therapy (RT) for soft tissue tumor is a debilitating complication with a high rate of nonunion that requires multiple subsequent procedures and hindrance of functional activity. We aimed to evaluate healing rate after repeated internal fixation in a case series of PFF after RT. We retrospectively reviewed the records of patients who had PFF after RT and were treated at our center between 2007 and 2018. We analyzed our surgical protocols and fracture healing rate. We identified and analyzed a total of seven patients (six females and one male) whose mean age at fracture was 58 years. Primary tumors consisted of soft tissue sarcoma (n = 5), melanoma (n = 1), and desmoid tumor (n = 1). All primary tumors were treated with surgical excision and adjuvant RT. The mean follow-up duration after fracture was 33 months (range, 16–58). At the last follow-up, five out of seven fractures had completely healed, and two lesions showed delayed union at 15 and 16 months, respectively. Among the five complete unions, one fracture was healed after the first fixation. The remaining four lesions were treated with second internal fixation due to nonunion/metal failure or delayed union. The mean time to radiologic healing after the last fixation was 6.8 months (range, 5–8). Our results suggest that bones within the RT field retain healing capacities, and that repeated internal fixation may be a viable option for the treatment of PFF after RT.

BackgroundSystemic inflammation plays a critical role in cancer progression and oncologic outcomes in cancer patients. We investigated whether preoperative inflammatory biomarkers, including C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and neutrophil to lymphocyte ratio (NLR), could be surrogate biomarkers for predicting overall survival (OS) in soft tissue sarcoma (STS) patients treated with surgery and postoperative radiotherapy.MethodsA series of 99 patients who presented with localized extremity STS were retrospectively reviewed. The preoperative CRP levels, ESR, and NLR were evaluated for associations with OS, disease-free survival (DFS), local recurrence-free survival (LRFS), and distant metastasis-free survival (DMFS). Cutoff values for CRP, ESR, and NLR were derived from receiver-operating characteristic curve analysis.ResultsElevated CRP (>0.14mg/dL), ESR (>15mm/h), and NLR (>1.95) levels were seen in 33, 44, and 45 patients, respectively. Of these three inflammatory biomarkers, elevated CRP and ESR were associated with a poorer OS (CRP: P=0.050; ESR: P=0.001), DFS (CRP: P=0.023; ESR: P=0.003), and DMFS (CRP: P=0.015; ESR: P=0.001). By multivariate analysis, an elevated ESR was found to be an independent prognostic factor for OS (HR 3.580, P=0.025) and DMFS (HR 3.850, P=0.036) after adjustment for other established prognostic factors.ConclusionsThe preoperative ESR level is a simple and useful surrogate biomarker for predicting survival outcomes in STS patients and might improve the identification of high-risk patients of tumor relapse in clinical practice.

Objectives This study was conducted to evaluate the added value of diffusion-weighted imaging (DWI) to conventional magnetic resonance imaging (MRI) for predicting fascial involvement of soft tissue sarcomas located in close proximity to fascial boundaries. Methods This retrospective study included 29 patients with surgically resected soft tissue sarcomas located in proximity to deep fascia and with a curvilinear tail-like hyperintensity in the adjacent fascia on T2-weighted images. All patients underwent conventional MRI and DWI at 3.0 T and had detailed histologic reports on involvement of fascia. Two musculoskeletal radiologists with 21 and 1 year of experience independently reviewed conventional MRI and conventional imaging with added DWI. Readers scored their confidence for tumor involvement of fascia using a three-point scale. Diagnostic performance (area under the curve [Az]) of the two MRI sets was assessed with receiver-operating characteristic curve analysis. Result Fascial involvement was present in 22/29 patients (75.9%). Both readers showed improvement in diagnostic performance with the addition of DWI (Az, from 0.545 to 0.792 and from 0.646 to 0.792 for reader 1 and reader 2, respectively). Adding DWI did not improve sensitivity or specificity for either reader ( p > 0.05). Interobserver agreement for the confidence scores improved from fair to moderate with the addition of DWI ( κ , from 0.390 to 0.560). Conclusions Adding DWI to conventional MRI improved diagnostic performance on prediction of fascial involvement of soft tissue sarcomas located in proximity to fascia, without significant improvement in sensitivity or specificity. Key Points • Adding DWI to conventional MRI improved readers’ confidence level for the prediction of fascial involvement of soft tissue sarcomas that are close to the deep fascia. • Addition of DWI also improved interobserver agreement. • Conversely, compared with conventional MRI, adding DWI did not significantly improve the sensitivity or specificity for the detection of fascial involvement.

AIM In the present study we assessed if postoperative radiotherapy (PORT) using conventional fractionation confers a benefit in cutaneous melanoma patients with lymph node (LN) metastasis. PATIENTS AND METHODS Sixty-two patients with axillary or inguinal LN metastasis were retrospectively reviewed. Twenty-eight patients received PORT. The median RT dose was 50 Gy in 25 fractions. The high-risk group was defined by the presence of any of the following: ≥3 LNs, size ≥3 cm, extranodal extension. RESULTS The median follow-up time was 34 months. PORT showed a significant benefit on 5-year axilla-inguinal recurrence-free survival (RFS) in high-risk patients (RT 100% vs. No-RT 37%, p=0.001). There was also a benefit of RT on 5-year out-field RFS in the high-risk population (RT 93% vs. No-RT 29%, p=0.002). There were no ≥grade 2 lymphedemas after RT. CONCLUSION PORT using conventional fractionation for high-risk LN metastasis from cutaneous melanoma is feasible with comparable regional control and minimal toxicity.

The occurrence of nontuberculous mycobacterial (NTM) infection is rare, and the involvement of the musculoskeletal system is even less common. However, the incidence of soft tissue and skin NTM infection is increasing, particularly in patients who undergo injections and minor surgical procedures. Given the non-specific clinical manifestations of NTM infection, the lack of knowledge among physicians regarding this rare infection could lead to inaccurate and delayed diagnosis. Herein, we present a case of an isolated subcutaneous NTM infection caused by Mycobacterium abscessus in the upper back of an immunocompetent 68-year-old woman. The clinical presentation, magnetic resonance imaging findings (including diffusion-weighted imaging), and pathologic findings of subcutaneous NTM infection are described and compared with those of tuberculosis and tumor presentations to provide a more accurate clinical picture for a differential diagnosis.

Malignant solitary fibrous tumor (MSFT) is a well-described entity, from which heterologous differentiation is extremely rare. We encountered a case of MSFT with rhabdomyosarcomatous differentiation in a 56-year-old man. This patient presented with a large mass in his posterior thigh. He had been treated with chemoradiation for sarcoma involving the cervical spine, right femoral head, and both lungs 6 months earlier. A wide excision was performed. The mass measured 10.6 cm and showed a fish-flesh cut surface with necrotic foci. Microscopically, the tumor showed heterogeneous cellularity with a hemangiopericytic vascular pattern. A hypercellular area showed spindle cells or epithelioid cells with high mitotic activity (63/10 high-power fields) and immunoreactivity for CD34 and CD99. A hypocellular area and a cystic area showed pleomorphic rhabdoid cells with immunoreactivity for desmin and myogenin. This is a report of a rare case of MSFT with rhabdomyosarcomatous differentiation and presents new histologic features of MSFT.

BACKGROUND Soft-tissue sarcomas (STS) of the distal extremities are a rare disease entity, hence proper treatment strategy is not well established. We evaluated the local control, survival and complications of treating sarcomas in the wrist, hand, ankle and foot with limb-sparing surgery (LSS) and postoperative radiotherapy (PORT). PATIENTS AND METHODS Seventeen patients with STS in wrist, hand, ankle and foot who received PORT after LSS from August 2008 to November 2015 were retrospectively reviewed. Primary outcome was 5-year local recurrence-free survival (LRFS). Secondary outcomes were 5-year distant metastasis-free survival (DMFS) and toxicities. RESULTS The median age was 32 (range=12-78) years. The most frequent STS location was the foot in 11 patients (64%) followed by two patients each in the wrist, hand and ankle, respectively. Fourteen patients (82%) underwent wide resection with flap grafts and the same number of patients achieved clear resection margins. The median postoperative radiation dose was 54 (range=46-60) Gy. Five patients also received chemotherapy. At a median follow-up of 39 (range=6-87) months, 5-year LRFS and DMFS were both 100%. Only one patient experienced grade 3 radiation dermatitis and there was no major wound complication. Radiation-induced bone fracture occurred in two patients. CONCLUSION PORT after LSS showed excellent local control for STS in the wrist, hand, ankle and foot. Considering the good local control and saving of limb function without any significant toxicity, the combination of LSS followed by PORT could be an appropriate and safe modality for STS of the distal extremities.

To investigate the diagnostic performance of MRI and PET-CT for the detection of loco-regional recurrences after soft tissue sarcoma (STS) excision.

Distinguishing dedifferentiated liposarcoma (DDLPS) from other high-grade spindle and pleomorphic sarcomas is important because of better prognosis in case of DDLPS. MDM2 amplification, a genetic abnormality of well-differentiated liposarcoma, is known to be present not only in DDLPS, but also in some other sarcomas. To differentiate DDLPS, we investigated MDM2 amplification and expression in high-grade spindle sarcomas. Eighty-five cases of nonlipogenic high-grade sarcomas, diagnosed between 2008 and 2011, were investigated. Tissue microarray, immunohistochemistry, and fluorescence in situ hybridization for MDM2 were performed. Forty-one of 85 cases (48.2%) showed MDM2 amplification and expression. Cases of MDM2 amplification were reclassified based on histology, immunophenotype, and clinical data. Thirty-nine of 41 cases, including those originally diagnosed as DDLPS (n=30), undifferentiated pleomorphic sarcoma (n=7), myxofibrosarcoma (n=1), and pleomorphic liposarcoma (n=1) could be reclassified as DDLPS. In addition, MDM2 immunohistochemistry and MDM2 fluorescence in situ hybridization showed an excellent correlation (P<0.001, sensitivity 92.7%, specificity 100%). MDM2 amplification and expression are potentially very useful in distinguishing between DDLPS and other undifferentiated high-grade spindle and pleomorphic sarcomas, even though a few other sarcomas also showed MDM2 amplification and expression.

Tumoral pseudogout is a rare clinical form of calcium pyrophosphate dihydrate crystal deposition disease. Tumoral pseudogout can mimic other diseases such as chondroid tumor, tophaceous gout, or tumoral calcinosis. Its radiological features have been presented in some case reports, but no specific radiographic features have been identified. Here, we report an unusual case of recurrent tumoral pseudogout involving the proximal interphalangeal joint of the right long finger. This case presents with progressive radiological findings of the disease with an enlarging and recurrent calcified mass and secondary bony erosion and remodeling, along with a radiological–pathological correlation. We also review previously reported imaging findings of this disease entity, differential points in comparison to other diseases, and some key points for making the correct diagnosis.

The present study describes the use of the "moving-shot'' technique for successful radiofrequency ablation (RFA) of malignant musculoskeletal soft-tissue tumors. Ultrasonography-guided RFA was performed in 6 malignant soft-tissue tumors in 5 patients. Short-term follow-up after RFA (8-27 weeks) showed that complete necrosis was achieved in all lesions, and 5 lesions (83%) decreased in size. Discomfort caused by the tumors decreased subjectively in all patients after ablation. Our results indicate that ultrasonography-guided RFA using the moving-shot technique can be an effective treatment option for locoregional control of malignant soft-tissue tumors. Long-term follow-up studies with a larger number of patients are necessary.

BACKGROUND:The aim of this study was to investigate the outcomes of cement arthroplasty used as a primary salvage procedure to treat ankle joint destruction. METHODS:This study included sixteen patients who underwent primary cement arthroplasty from May 2004 to March 2012 because of an ankle disorder, including intractable infection, nonunion, or a large bone defect or tumor. The mean age of the patients was fifty-seven years (range, twenty-three to seventy-four years), and the mean follow-up period was thirty-nine months (range, fourteen to 100 months). The cement spacer position, cement breakage, osteolysis around the inserted cement, and alignment of the joint were evaluated radiographically. American Orthopaedic Foot & Ankle Society (AOFAS) scores and visual analogue scale (VAS) pain scores were recorded preoperatively and at the time of final follow-up. Functional questionnaires were used to assess the duration for which the patient could walk continuously, use of walking aids, sports activity, consumption of pain medication, and the patient's subjective assessment of the percentage of overall improvement compared with before the cement arthroplasty. RESULTS:The cement spacer was retained without breakage for a mean of thirty-nine months (range, fourteen to 100 months). Osteolysis around the cement was observed in one patient at seventy-eight months, and subluxation developed in one patient. The mean AOFAS and VAS pain scores improved from 39 (range, 11 to 71) preoperatively to 70 (range, 47 to 88) postoperatively (p = 0.001) and from 8 (range, 4 to 9) to 3 (range, 1 to 7) (p = 0.001), respectively. At the final follow-up evaluation, nine of the sixteen patients did not require walking aids, ten used no pain medication, and nine were able to walk continuously for more than an hour. One patient complained of persistent pain and was considered to have had a failure of the procedure. CONCLUSIONS:Primary cement arthroplasty might be a treatment option for advanced ankle destruction in elderly and less active patients. LEVEL OF EVIDENCE:Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.