scholarly journals Risk factors and outcomes for failure of biological reconstruction after resection of primary malignant bone tumors in the extremities

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Taweechok Wisanuyotin ◽  
Permsak Paholpak ◽  
Winai Sirichativapee ◽  
Weerachai Kosuwon
Keyword(s):  
Risk Factors ◽  
Functional Outcomes ◽  
Bone Tumors ◽  
Tumor Resection ◽  
Tumor Location ◽  
Complication Rates ◽  
Malignant Bone Tumors ◽  
Biological Reconstruction ◽  
Significant Difference ◽  
Autograft Group

AbstractBiological reconstruction is widely used to reconstruct bone defects after resection of bone tumors in the extremities. This study aimed to identify risk factors for failure and to compare outcomes of the allograft, nonvascularized autograft, and recycled frozen autograft reconstruction after resection of primary malignant bone tumors in the extremities. A retrospective study was performed at a single center between January 1994 and December 2017. Ninety patients with primary malignant bone tumors of the extremities were treated with tumor resection and reconstruction using one of three bone graft methods: nonvascularized autograft (n = 27), allograft (n = 34), and recycled frozen autograft (n = 29). The median time for follow-up was 59.2 months (range 24–240.6 months). Overall failure of biological reconstruction occurred in 53 of 90 patients (58.9%). The allograft group had the highest complication rates (n = 21, 61.8%), followed by the recycled frozen autograft (n = 17, 58.6%) and nonvascularized autograft (n = 15, 55. 6%) groups. There was no statistically significant difference among these three groups (p = 0.89). The mean MSTS score was 22.6 ± 3.4 in the nonvascularized autograft group, 23.4 ± 2.6 in the allograft group, and 24.1 ± 3.3 in the recycled frozen autograft group. There was no significant difference among the groups (p = 0.24). After bivariate and multivariable analyses, patient age, sex, tumor location, graft length, methods, and type of reconstruction had no effects on the failure of biological reconstruction. Biological reconstruction using allograft, nonvascularized autograft, and recycled frozen autograft provide favorable functional outcomes despite high complication rates. This comparative study found no significant difference in functional outcomes or complication rates among the different types of reconstruction.

scholarly journals Pedicle frozen autograft-prosthesis composite reconstructions for malignant bone tumors of the proximal femur

2019 ◽  
Author(s):  
gang xu ◽  
Shinji Miwa ◽  
Norio Yamamoto ◽  
Katsuhiro Hayashi ◽  
Akihiko Takeuchi ◽  
...  
Keyword(s):  
Proximal Femur ◽  
Functional Outcomes ◽  
Bone Tumors ◽  
Tumor Resection ◽  
Malignant Bone Tumors ◽  
Musculoskeletal Tumor ◽  
Musculoskeletal Tumor Society ◽  
Biological Reconstruction ◽  
The Mean

Abstract Background Limb salvage surgery is becoming increasingly popular after tumor resection in the lower extremity. Biological reconstruction and use of megaprosthesis are main methods for malignant bone tumors of the proximal femur, which remain controversial due to short- and long-term complication in the proximal femur. Tumor-bearing bone treated by liquid nitrogen is one of biological reconstruction. This study aimed to evaluate the mid- and long-term functional outcomes and complications in patients treated with frozen autograft–prosthesis composite (FAPC) reconstructions in the proximal femur. Methods This retrospective study included 19 patients (10 women, 9 men) with malignant tumors of the proximal femur who underwent tumor-wide resection and FAPC reconstruction (mean age, 46 years; range, 9-77 years). The mean follow-up period of 66 months (range, 9-179 months). Functional outcomes, oncological outcome and complications were evaluated by Musculoskeletal Tumor Society score, clinical and radiological examinations. Results The overall survival rate was 68.4%, and the mean Musculoskeletal Tumor Society functional score was 26.4 points (88%). FAPC survival rates were 100% and 50% at 5 and 10 years, respectively. Five of the 19 patients (26%) had complications: 2 required prosthesis removal and 2 developed a deep infection around acetabular. Wear of the acetabulum occurred in 2 cases, while disease recurrence was occurred in 1 case. There were no cases of greater trochanter avulsion, obvious absorption around frozen bone, prosthesis loosening or leg length discrepancy. Conclusions Due to without femoral osteotomy, ease of soft-tissue attachment and preservation of bone matrix, FAPC reconstruction provide early limb stability and satisfactory functional outcome after malignant bone tumor resection in the proximal femur.

scholarly journals Pedicle frozen autograft-prosthesis composite reconstructions for malignant bone tumors of the proximal femur

2020 ◽  
Author(s):  
gang xu ◽  
Shinji Miwa ◽  
Norio Yamamoto ◽  
Katsuhiro Hayashi ◽  
Akihiko Takeuchi ◽  
...  
Keyword(s):  
Proximal Femur ◽  
Functional Outcomes ◽  
Bone Tumors ◽  
Functional Score ◽  
Malignant Bone Tumors ◽  
Musculoskeletal Tumor ◽  
Musculoskeletal Tumor Society ◽  
Biological Reconstruction ◽  
The Mean

Abstract Background Limb salvage surgery is becoming increasingly popular after tumor resection in the lower extremity. Biological reconstruction and use of megaprosthesis are main methods for malignant bone tumors of the proximal femur, which remain controversial due to short- and long-term complication in the proximal femur. Tumor-bearing bone treated by liquid nitrogen is one of biological reconstruction. This study aimed to evaluate the mid- and long-term functional outcomes and complications in patients treated with frozen autograft–prosthesis composite (FAPC) reconstructions in the proximal femur. Methods This retrospective study included 19 patients (10 women, 9 men) with malignant tumors of the proximal femur who underwent tumor-wide resection and FAPC reconstruction (mean age, 46 years; range, 9-77 years). The mean follow-up period of 69 months (range, 9-179 month). Functional outcomes, oncological outcomes and complications were evaluated by Musculoskeletal Tumor Society score, clinical and radiological examinations. Results The overall survival rate was 68.4%, and the mean Musculoskeletal Tumor Society functional score was 26.4 points (88%). FAPC survival rates were 100% and 50% at 5 and 10 years, respectively. Five of the 19 patients (26%) had complications: 2 required prosthesis removal and 2 developed a deep infection around acetabular. Wear of the acetabulum occurred in 2 cases, while disease recurrence was occurred in 1 case. There were no cases of greater trochanter avulsion, obvious absorption around frozen bone, prosthesis loosening or leg length discrepancy. Conclusions Due to without femoral osteotomy, this technique features satisfactory functional outcome and provide biomechanical stability that is comparable to those of other methods of biological reconstruction or megaprosthesis.

scholarly journals Pedicle frozen autograft-prosthesis composite reconstructions for malignant bone tumors of the proximal femur

2020 ◽  
Author(s):  
gang xu ◽  
Shinji Miwa ◽  
Norio Yamamoto ◽  
Katsuhiro Hayashi ◽  
Akihiko Takeuchi ◽  
...  
Keyword(s):  
Proximal Femur ◽  
Functional Outcomes ◽  
Bone Tumors ◽  
Functional Score ◽  
Malignant Bone Tumors ◽  
Musculoskeletal Tumor ◽  
Musculoskeletal Tumor Society ◽  
Biological Reconstruction ◽  
The Mean

Abstract Background Limb salvage surgery is becoming increasingly popular after tumor resection in the lower extremity. Biological reconstruction and use of megaprosthesis are main methods for malignant bone tumors of the proximal femur, which remain controversial due to short- and long-term complication in the proximal femur. Tumor-bearing bone treated by liquid nitrogen is one of biological reconstruction. This study aimed to evaluate the mid- and long-term functional outcomes and complications in patients treated with frozen autograft–prosthesis composite (FAPC) reconstructions in the proximal femur. Methods This retrospective study included 19 patients (10 women, 9 men) with malignant tumors of the proximal femur who underwent tumor-wide resection and FAPC reconstruction (mean age, 46 years; range, 9-77 years). The mean follow-up period of 69 months (range, 9-179 month). Functional outcomes, oncological outcomes and complications were evaluated by Musculoskeletal Tumor Society score, clinical and radiological examinations. Results The overall survival rate was 68.4%, and the mean Musculoskeletal Tumor Society functional score was 26.4 points (88%). FAPC survival rates were 100% and 50% at 5 and 10 years, respectively. Five of the 19 patients (26%) had complications: 2 required prosthesis removal and 2 developed a deep infection around acetabular. Wear of the acetabulum occurred in 2 cases, while disease recurrence was occurred in 1 case. There were no cases of greater trochanter avulsion, obvious absorption around frozen bone, prosthesis loosening or leg length discrepancy. Conclusions Due to without femoral osteotomy, this technique features satisfactory functional outcome and provide biomechanical stability that is comparable to those of other methods of biological reconstruction or megaprosthesis.

Integrated dual lag screws versus single lag screw cephalomedullary nail constructs: a meta-analysis and systematic review

2021 ◽  
pp. 112070002098506
Author(s):  
James R Onggo ◽  
Mithun Nambiar ◽  
Jason D Onggo ◽  
Anuruban Ambikaipalan ◽  
Parminder J Singh ◽  
...  
Keyword(s):  
Functional Outcomes ◽  
Meta Analysis ◽  
Femoral Fractures ◽  
Harris Hip Score ◽  
Complication Rates ◽  
Non Union ◽  
Lag Screw ◽  
Significant Difference ◽  
Lower Complication ◽  
Cephalomedullary Nails

Background/Aim: This study aims to determine the safety and efficacy of integrated dual lag screw (IDL) cephalomedullary nails (CMN) when compared with single lag screw (SL) constructs, in the internal fixation of intertrochanteric femoral fractures. Methods: The Smith & Nephew InterTan IDL was compared with SL CMN group consisting of the Stryker Gamma-3 (G3) and Synthes Proximal Femoral Nail Antirotation (PFNA) CMN. A multi-database search was performed according to PRISMA guidelines. Data from studies assessing the clinical and radiological outcomes, complications and perioperative parameters of InterTan versus G3 or PFNA CMN in patients with intertrochanteric femoral fractures were extracted and analysed. Results: 15 studies were included in this meta-analysis, consisting of 2643 patients. InterTan was associated with lower complication rates in terms of all-cause revisions (OR 0.34; 95% CI, 0.22–0.51; p < 0.001), cut-outs (OR 0.30; 95% CI, 0.17–0.51; p < 0.001), medial or lateral screw migration (OR 0.19; 95% CI, 0.06–0.65; p = 0.008) as well as persistent hip and thigh pain (OR 0.65; 95% CI, 0.47–0.90; p = 0.008). In terms of perioperative parameters, InterTan is associated with longer operative times (MD 5.57 minutes; 95% CI, 0.37–10.78 minutes, p = 0.04) and fluoroscopy times (MD 38.89 seconds, 95% CI, 15.88–61.91 seconds; p < 0.001). There was no statistically significant difference in terms of clinical Harris Hip Score and radiological outcomes, non-union, haematoma, femoral fractures, varus collapse, length of stay and mean intraoperative blood loss between the 2 groups. Conclusions: Integrated dual lag screw cephalomedullary nails are associated with fewer revisions and complications. However, there is insufficient data to suggest that either nail construct is associated with better functional outcomes.

scholarly journals Retrospective analysis of LNM risk factors and the effect of chemotherapy in early colorectal cancer: A Chinese multicenter study

BMC Cancer ◽  
2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Chunyan Zeng ◽  
Dandan Xiong ◽  
Fei Cheng ◽  
Qingtian Luo ◽  
Qiang Wang ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Risk Factors ◽  
Multicenter Study ◽  
Tumor Size ◽  
Lymphovascular Invasion ◽  
Univariate Analysis ◽  
Tumor Location ◽  
Early Colorectal Cancer ◽  
Depth Of Invasion ◽  
Significant Difference

Abstract Background Estimating the risk of lymph node metastasis (LNM) is crucial for determining subsequent treatments following curative resection of early colorectal cancer (ECC). This multicenter study analyzed the risk factors of LNM and the effectiveness of postoperative chemotherapy in patients with ECC. Methods We retrospectively analyzed the data of 473 patients with ECC who underwent general surgery in five hospitals between January 2007 and October 2018. The correlations between LNM and sex, age, tumor size, tumor location, endoscopic morphology, pathology, depth of invasion and tumor budding (TB) were directly estimated based on postoperative pathological analysis. We also observed the overall survival (OS) and recurrence in ECC patients with and without LNM after matching according to baseline measures. Results In total, 473 ECC patients were observed, 288 patients were enrolled, and 17 patients had LNM (5.90%). The univariate analysis revealed that tumor size, pathology, and lymphovascular invasion were associated with LNM in ECC (P = 0.026, 0.000, and 0.000, respectively), and the multivariate logistic regression confirmed that tumor size, pathology, and lymphovascular invasion were risk factors for LNM (P = 0.021, 0.023, and 0.001, respectively). There were no significant differences in OS and recurrence between the ECC patients with and without LNM after matching based on baseline measures (P = 0.158 and 0.346, respectively), and no significant difference was observed between chemotherapy and no chemotherapy in ECC patients without LNM after surgery (P = 0.729 and 0.052). Conclusion Tumor size, pathology, and lymphovascular invasion are risk factors for predicting LNM in ECC patients. Adjuvant chemotherapy could improve OS and recurrence in patients with LNM but not always in ECC patients without LNM.

scholarly journals Endoprosthetic Reconstruction in Limb Salvage for Malignant Bone Tumours in Children

2021 ◽  
Vol 2 (2) ◽  
pp. 4-8
Author(s):  
Sagar Tontanahal ◽  
Gahukamble Abhay Deodas ◽  
Deeptiman James ◽  
Anand Kurian ◽  
Thomas Palocaren
Keyword(s):  
Limb Salvage ◽  
Bone Tumors ◽  
Rapid Development ◽  
Tumor Resection ◽  
Limb Salvage Surgery ◽  
Endoprosthetic Reconstruction ◽  
Malignant Bone Tumors ◽  
Musculoskeletal Tumor Society ◽  
Prosthetic Reconstruction ◽  
Malignant Bone Tumours

Background: The management of malignant bone tumors in children has come a long way in the past few decades. The transition from amputation to limb salvage has been made possible due to the rapid development in the diagnosis and the oncological management of these malignant tumors. However, there exist significant reservations regarding endoprosthetic reconstruction in children. Material and methods: A mini-review was conducted of articles detailing the use of prosthetic reconstruction following tumor resection in children. The data regarding complications and functional outcomes following surgery were collected and presented. Results: The studies reviewed reported a 5-year survival rate between 60 – 70 %. Uniform across the studies was the need for multiple surgeries when endoprosthesis was used for limb reconstruction, ranging between 2.8 – 3.5 surgeries. The most common complication noted across the studies was related to soft tissue problems such as joint instability followed by structural failure of the prosthesis. Infections were noted with a frequency of 10 – 15 %. Studies showed successful management of limb length discrepancy with expandible prosthesis. Musculoskeletal Tumor Society (MSTS) score used to evaluate the functional outcome showed satisfactory outcomes. Conclusion: Limb salvage surgery, with recent advances in technique and prosthesis design, is an attractive option in children with extremity malignant bone tumors. In recent time, endoprosthetic reconstruction of extremities have yielded good functional results and are well accepted by the child and the parents. The purpose of this mini-review is to shed some light on the use of endoprosthetic reconstruction in children following tumor resection with its potential benefits and drawbacks.

scholarly journals Retrospective analysis for the LNM risk factors and effect of chemotherapy for the early colorectal cancer: A Chinese multicenter study

2020 ◽  
Author(s):  
Chunyan Zeng ◽  
Dandan Xiong ◽  
Fei Cheng ◽  
Qingtian Luo ◽  
Qiang Wang ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Risk Factors ◽  
Multicenter Study ◽  
Tumor Size ◽  
Lymphovascular Invasion ◽  
Univariate Analysis ◽  
Tumor Location ◽  
Early Colorectal Cancer ◽  
Depth Of Invasion ◽  
Significant Difference

Abstract Background Estimating the risk of lymph node metastasis (LNM) is crucial for determining subsequent treatments following curative resection of early colorectal cancer (ECC). This multicenter study analyzed the risk factors of LNM and the effectiveness of postoperative chemotherapy in patients with ECC.Methods We retrospectively analyzed the data of 473 patients with ECC who underwent general surgery in five hospitals between January 2007 and October 2018. The correlations between LNM and sex, age, tumor size, tumor location, endoscopic morphology, pathology, depth of invasion and tumor budding (TB) were directly estimated based on postoperative pathological analysis. We also observed the overall survival (OS) and recurrence in ECC patients with and without LNM after matching according to baseline measures. Results In total, 473 ECC patients were observed, 288 patients were enrolled, and 17 patients had LNM (5.90%). The univariate analysis revealed that tumor size, pathology, and lymphovascular invasion were associated with LNM in ECC (P=0.026, 0.000, and 0.000, respectively), and the multivariate logistic regression confirmed that tumor size, pathology, and lymphovascular invasion were risk factors for LNM (P=0.021, 0.023, and 0.001, respectively). There were no significant differences in OS and recurrence between the ECC patients with and without LNM after matching based on baseline measures (P=0.158 and 0.346, respectively), and no significant difference was observed between chemotherapy and no chemotherapy in ECC patients without LNM after surgery (P=0.729 and 0.052).Conclusion Tumor size, pathology, and lymphovascular invasion are risk factors for predicting LNM in ECC patients. Adjuvant chemotherapy could improve OS and recurrence in patients with LNM but not always in ECC patients without LNM.

scholarly journals Retrospective analysis for the LNM risk factors and effect of chemotherapy for the early colorectal cancer: A Chinese multicenter study

2020 ◽  
Author(s):  
Chunyan Zeng ◽  
Dandan Xiong ◽  
Fei Cheng ◽  
Qingtian Luo ◽  
Qiang Wang ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Risk Factors ◽  
Multicenter Study ◽  
Tumor Size ◽  
Lymphovascular Invasion ◽  
Univariate Analysis ◽  
Tumor Location ◽  
Early Colorectal Cancer ◽  
Depth Of Invasion ◽  
Significant Difference

Abstract Background Estimating the risk of lymph node metastasis (LNM) is crucial for determining subsequent treatments following curative resection of early colorectal cancer (ECC). This multicenter study analyzed the risk factors of LNM and the effectiveness of postoperative chemotherapy in patients with ECC.Methods We retrospectively analyzed the data of 473 patients with ECC who underwent general surgery in five hospitals between January 2007 and October 2018. The correlations between LNM and sex, age, tumor size, tumor location, endoscopic morphology, pathology, depth of invasion and tumor budding (TB) were directly estimated based on postoperative pathological analysis. We also observed the overall survival (OS) and recurrence in ECC patients with and without LNM after matching according to baseline measures. Results In total, 473 ECC patients were observed, 288 patients were enrolled, and 17 patients had LNM (5.90%). The univariate analysis revealed that tumor size, pathology, and lymphovascular invasion were associated with LNM in ECC (P=0.026, 0.000, and 0.000, respectively), and the multivariate logistic regression confirmed that tumor size, pathology, and lymphovascular invasion were risk factors for LNM (P=0.021, 0.023, and 0.001, respectively). There were no significant differences in OS and recurrence between the ECC patients with and without LNM after matching based on baseline measures (P=0.158 and 0.346, respectively), and no significant difference was observed between chemotherapy and no chemotherapy in ECC patients without LNM after surgery (P=0.729 and 0.052).Conclusion Tumor size, pathology, and lymphovascular invasion are risk factors for predicting LNM in ECC patients. Adjuvant chemotherapy could improve OS and recurrence in patients with LNM but not always in ECC patients without LNM.

Effect of stress-induced hyperglycemia after non-traumatic non-aneurysmal subarachnoid hemorrhage on clinical complications and functional outcomes

2021 ◽  
Author(s):  
Zeyu Zhang ◽  
Yue Zhao ◽  
Yibo Liu ◽  
Xiaoyu Wang ◽  
Houshi Xu ◽  
...  
Keyword(s):  
Risk Factors ◽  
Subarachnoid Hemorrhage ◽  
Cerebral Infarction ◽  
Functional Outcomes ◽  
Aneurysmal Subarachnoid Hemorrhage ◽  
Complication Rates ◽  
Poor Outcome ◽  
Clinical Complications ◽  
Symptomatic Vasospasm ◽  
Poor Outcomes

Abstract Background Despite having an overall benign course, non-traumatic non-aneurysmal subarachnoid hemorrhage (naSAH) is still accompanied by a risk of clinical complications and poor outcomes. Risk factors and mechanisms of complications and poor outcomes after naSAH remain unknown. Our aim was to explore the effect of stress-induced hyperglycemia (SIH) on complication rates and functional outcomes in naSAH patients. Methods We retrospectively reviewed patients with naSAH admitted to our institution between 2013 and 2018. SIH was identified according to previous criterion. Symptomatic vasospasm, delayed cerebral infarction, and hydrocephalus were identified as main complications. Outcomes were reviewed using a modified Rankin Scale (mRS) at discharge, 3 months, and 12 months. A statistical analysis of clinical, radiological, and laboratory risk factors of complications and outcomes was conducted. Results 244 naSAH patients were incorporated in the cohort with 74 (30.3%) SIH. After adjusting for age, gender, hypertension, Hunt and Hess (HH) grade, modified Fisher Scale (mFS), intraventricular hemorrhage (IVH), and subarachnoid blood distribution, SIH was significantly associated with symptomatic vasospasm (P < 0.001, 12.176 [4.904–30.231]), delayed cerebral infarction (P < 0.001, 12.434 [3.850-40.161]), hydrocephalus (P = 0.008, 5.771 [1.570-21.222]), and poor outcome at 12 months (P = 0.006, 5.506 [1.632–18.581]), whereas the correlation between SIH and poor outcome at discharge (P = 0.064, 2.409 [0.951-6.100]) or 3 months (P = 0.110, 2.029 [0.852–4.833]) was not significant. Incorporation of SIH increased the area under curve (AUC) of ROC in the combined model for predicting symptomatic vasospasm (P = 0.002), delayed cerebral infarction (P = 0.024), hydrocephalus (P = 0.037), and 12-month poor outcome (P = 0.087). Conclusions SIH is a significant and independent risk factor for symptomatic vasospasm, delayed cerebral infarction, hydrocephalus, and long-term poor outcome in naSAH patients. Identifying SIH early after naSAH is important for decision-making and treatment planning.

scholarly journals Supratentorial and Infratentorial Approaches to Pineal Surgery: A Database Analysis

2018 ◽  
Vol 80 (04) ◽  
pp. 364-370
Author(s):  
David M. Rosenberg ◽  
Brett W. Geever ◽  
Akash S. Patel ◽  
Anisse N. Chaker ◽  
Abhiraj D. Bhimani ◽  
...  
Keyword(s):  
Pineal Gland ◽  
Clinical Decision Making ◽  
Tumor Resection ◽  
Postoperative Outcomes ◽  
Complication Rates ◽  
Database Analysis ◽  
Improvement Program ◽  
Multicenter Studies ◽  
Patient Demographics ◽  
Significant Difference

Objectives Neoplasms involving the pineal gland are rare. When they do occur, tumor resection is anatomically challenging and is traditionally addressed by either a supratentorial or an infratentorial approach. To date, no large, multicenter studies have been performed that systematically analyze outcomes comparing these two approaches. This study aimed to evaluate outcomes for patients undergoing pineal neoplasm resection, comparing supratentorial and infratentorial approaches. Design Retrospective database review. Setting Multi-institutional database. Participants From 2005 to 2016, 60 patients were identified, with 13 undergoing a supratentorial approach and 47 undergoing an infratentorial approach. Main Outcome Measures Patient demographics, comorbidities, and 30-day postoperative outcomes were investigated using the American College of Surgeons National Surgical Quality Improvement Program database. Demographics, readmission, reoperation, and complication rates were analyzed and compared with previous studies. Results Patient demographics were similar between these two groups. The overall complication rates for the supratentorial and infratentorial approaches were 30.8 and 17%, respectively, and the difference was not statistically significant. The most common medical complications encountered were respiratory and hematological. Conclusion As the first multi-institutional database analysis of approaches to the pineal gland, this study provides an analysis of patient demographics, comorbidities, and postoperative complications. After controlling for preoperative risk factors and demographic characteristics, no statistically significant differences in postoperative outcomes were found between infratentorial and supratentorial approaches. The mean readmission, reoperation, and complication rates were found to be 2.1, 8.3, and 20%, respectively. The lack of significant difference between approaches suggests that clinical decision-making should depend upon anatomical considerations and physician preference, although the complications illustrated here may provide some preoperative guidance.

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