Background. Joint-sparing limb salvage surgery (JSLSS) is an advancement in the techniques and concepts of limb salvage surgery, which makes it possible to save not only the limb affected by malignancy but also the adjacent joint and the epiphyseal plate. In the growing child, this procedure is technically demanding due to the availability of small length of bone for implant purchase. Reconstruction options can be biological reconstruction or endoprosthesis; however, the outcome of endoprosthetic reconstruction after joint-sparing resection is not well described in the literature. Purposes. (1) To determine the prosthesis survival rates when using customized Joint-Sparing Endoprosthesis (JSE) after juxta-articular resection of bone tumors, (2) to investigate the rates of local recurrence, (3) to evaluate the need for revision surgery, and (4) to compare the outcome of customized JSE with that of joint-sacrificing techniques. Methods. In our study, joint sparing is defined as any procedure where a custom-made JSE is used in lieu of sacrificing the adjacent joint whenever the length of the remaining bone segment is not enough to accommodate the stem of a modular implant. Twenty-eight patients received JSE, and 31 joints were spared. Their age ranged from 4 to 55 years with a median age of 13 years. Twenty-one patients received surgery for primary reconstruction and 7 patients for revision of failed bone allograft or modular implant. Twenty-four joints are spared in the lower limbs and 7 in the upper limbs. Osteosarcoma was the most common pathological diagnosis (n = 13). Flat surface HA-coated custom JSE was used to spare 15 joints, and short-stemmed custom JSE was used to spare 16 joints. The length of the remaining bone epiphysis for JSE anchorage from the knee and ankle joints was 25–75 mm, median = 45 mm, and the length of the cortical bone remaining for the proximal femur and distal humerus was 5–70 mm, median = 10 mm. Results. Operative time was 2.5 to 4 hours (avg. 3 hr.) The bone resection surface fitted the prosthesis surface with <2 mm difference. Histological examination of all resected specimens shows clear bone resection margins; 2 patients had positive soft tissue margins. At mean follow-up period of 3 years (6 months–10 years), 6 patients developed local and systemic recurrences, three of them had a pathological fracture at the time of diagnosis (P=0.139), and 4 showed a poor response to chemotherapy (P=0.014); all recurrences occurred in the soft tissue. Implant survival at 5 years was 86.15%, and MSTS score was 90% (83–96%). Conclusions. Whenever this kind of implant is affordable and can be utilized, particularly in younger age groups, JSE may be a good reconstruction option to avoid the use of expandable implants and to avoid the potentially higher revision and complication rates associated with biological reconstruction, as well as the complications of conventional joint-sacrificing implant, mainly dislocations and polyethylene wear and tear.

Background: Malignant peripheral nerve sheath tumor is a rare and aggressive form of sarcoma that arises from a peripheral nerve, mostly in association with neurofibromatosis type 1. Half of the cases were reported in the extremities, with the lungs being the most common site of metastasis. We report a rare case of successful limb salvage surgery performed for a large exophytic malignant peripheral nerve sheath tumor of the right forearm with wide surgical margins followed by split-thickness skin graft and later a flexor carpi radialis tendon transfer to extensor digitorum communis tendon. Case presentation: A 51-year-old Bedouin Arabic man presented to our institution with an incompletely excised, large, fungating, malignant peripheral nerve sheath tumor occupying most of his right forearm. Staging imaging showed multiple lung nodules. He underwent wide local excision followed by skin graft and tendon transfer as a palliative measure to preserve the function of his dominant limb. The operation was performed without any complications, and the patient had an excellent postoperative result. Afterward, he was started on multiple lines of chemotherapy that failed because of disease progression, and the patient died 7 months after the operation. Conclusion: Clinicians must consider the possibility of soft tissue sarcoma even in a patient with a small, slow-growing, superficial mass. Furthermore, a wrong open biopsy or nononcological surgical procedure may lead to possible contamination and ultimately a more radical procedure than would have originally been necessary, where this can be prevented by an early referral to a highly specialized sarcoma center.

Background: CIC-rearranged sarcoma is a rare and aggressive type of undifferentiated round cell tumor characterized by CIC gene fusion, most commonly CIC::DUX4. This study presents a series of eleven cases, highlighting their clinicopathological features. Methods: Pathology records (2019 to 2024) were searched using “sarcoma with CIC”, identifying eleven cases, of which seven referred cases were initially misdiagnosed. Pathological and clinical analysis was conducted. Treatment was dictated upon multidisciplinary panel discussion based on tumor stage. Follow-up data (1–25 months) was available for all patients. Results: The cohort included six males and five females, with a median age of 43 years (range;14–53), with nine in soft tissue and two in bone. Tumor size ranged from 3.5 cm to 20.0 cm (mean: 9.8 cm). Most cases showed sheets of undifferentiated round- to oval-shaped cells. Two cases showed an Ewing-like pattern, and one case showed spindle cells in a fibrotic stroma transitioning to epithelioid cells. Necrosis was present in nine cases, and mitotic count ranged from 2 to 38/ 10HPFs (mean = 14.2). CD99 was positive in (10/11) cases and WT-1 in (6/9). NKX2.2, S100, and MDM2 were positive in rare cases. CIC::DUX4 fusion was detected in four cases. FISH for CIC gene rearrangement was positive in seven cases, two of them confirmed by methylation analysis. Metastasis at diagnosis was common (n = 8), primarily in the lungs, with later metastasis to the brain and bone. At time of final analysis, eight patients died within a median of 10 months (range: 1–19 months), while three were alive, two with stable disease (for a period of 6 and 25 months) and one with progression after 10 months. Significant correlation was seen between overall survival and the presence of metastasis at diagnosis (p value = 0.03). Conclusions: CIC-rearranged sarcomas are rare, high-grade tumors with predilection for soft tissue. Misdiagnosis is frequent, necessitating molecular confirmation. These tumors are treatment-resistant, often present with lung metastasis, and carry a poor prognosis, especially with initial metastasis.

To assess the impact of delay in local control on survival outcomes of Ewing sarcoma (ES) patients. The cornerstone of therapy of localized ES includes chemotherapy and local control with surgery or radiotherapy. We sought to assess the impact of delay (>15 weeks) in timing of local control on survival outcomes of ES patients. Data of consecutive patients with primary non-metastatic ES of the extremities, treated at a single institution were collected. The impact of delay of timing for local control, demographics, and disease characteristics on overall survival (OS) was analyzed. A total of 43 patients with ES of the extremity were included. All patients received neoadjuvant chemotherapy. Local control was by surgery in 36 patients and definitive radiation in 7. A total of 16 patients had delay in local control. At a median follow of up of 48 months, patients with delay in local control had significantly inferior OS compared to those with optimal local control timing (5-year OS 56% vs. 80%, respectively, p = 0.044). Other factors that predicted inferior OS included definitive radiation as opposed to definitive surgery (5-year OS 25% vs. 79%, respectively, p = 0.041) and tumor necrosis <90% as opposed to ≥90% (5-year OS 55% vs. 90%, respectively, p = 0.01). Delay in definitive therapy, local control with radiation as opposed to surgery and poor post-chemotherapy tumor necrosis predict inferior OS in ES. Adopting strategies to minimize delay in local control could improve survival outcomes.