Synovial sarcoma (SS) represents a rare malignant type of soft tissue sarcoma (STS) with uncertain differentiation accounting for 5%-10% of all STS. Primary renal synovial sarcoma (PRSS) is very rare, with only about 205 documented cases so far with predominantly monophasic morphology. Clinical and radiological presentations of PRSS as renal mass, abdominal pain and haematuria often make it difficult to distinguish from other renal malignancies like renal cell carcinoma (RCC). The occurrence of both carcinoma and sarcoma simultaneously in the same kidney is rare. Due to the rarity and severity of the disease, diagnosis and management rely on a multidisciplinary approach. Here we reported a diagnostically challenging case of a patient in his 50s with primary biphasic SS of the kidney with synchronous clear cell RCC. To the best of our knowledge, this is the first documented case of a patient developing PRSS with synchronous clear cell RCC.

SummaryKaposiform haemangioendothelioma (KHE) is a rare, locally aggressive vascular tumour typically presenting in infancy and early childhood. We report the case of a female child of early school age who presented with progressive swelling and discolouration of the pulp of the right middle finger. The lesion originated from the pulp of the finger and was initially misdiagnosed as chronic osteomyelitis at another centre. Subsequent evaluation established the diagnosis of primary KHE and the patient underwent wide local excision.However, the patient developed local recurrence 10 months following the index procedure. The recurrence was managed with amputation through the middle phalanx. At the 3-month follow-up post-amputation, the patient remains asymptomatic with no evidence of recurrence and reports a satisfactory functional outcome, being pain-free and well adapted.This case highlights the diagnostic challenges and potential for recurrence in KHE arising from the distal phalanx pulp. It underscores the importance of considering KHE in the differential diagnosis of persistent digital swellings in children, particularly when conventional treatment fails, and emphasises the need for close follow-up and appropriate surgical planning to achieve optimal outcomes.

Achieving local control in pediatric soft tissue sarcoma using a combination of surgical resection and/or radiotherapy (RT) requires complex decision-making that benefits from multi-disciplinary discussion. While there is a paucity of data in the pediatric and adolescent and young adult (AYA) population, neoadjuvant RT is routinely utilized in adult practice with several benefits to this approach. This review from the APSA Cancer Committee in collaboration with colleagues in radiation oncology aims to provide a summary of the current literature regarding optimal timing of radiation therapy for patients with soft tissue sarcoma. We aim to address the practical challenges that perioperative RT portends and offer insight for maximizing both oncologic and functional outcomes in the pediatric population.

Background and Clinical Significance: Intimal sarcoma is a rare, aggressive malignancy of the large arteries that grows within the vessel lumen and frequently mimics thromboembolic disease, leading to diagnostic delay. Flow restoration and tissue biopsy are both difficult if the tumour occupies a technically demanding arterial segment, which is further aggravated if conventional large-bore arterial access is precluded by peripheral arterial disease. Case Presentation: A 66-year-old woman with multiple cardiovascular risk factors presented with subacute left upper-limb ischaemia and painless digital cyanosis (embolic phenomena) that had progressed despite therapeutic anticoagulation. Computed tomography angiography demonstrated a sub-occlusive filling defect extending from the origin of the left subclavian artery towards the aortic arch, initially interpreted as thrombus. There were no clear signs of malignant disease, despite differential screenings. Multiple on- and off-site surgical consultations were done, but the patient was repeatedly rejected for operation due to disease characteristics and high surgical risk. Severe iliofemoral peripheral arterial disease precluded usual transfemoral arterial delivery of a large-bore system, so the subclavian mass was aspirated using a 22/26-French sheath and extracorporeal aspiration system (AngioVac System (AngioDynamics)) delivered through percutaneous transcaval (caval-aortic) access, under cerebral embolic protection. Repeated aspiration runs with mechanical snare augmentation achieved substantial debulking, angiographic normalisation of flow and abolition of the invasive pressure gradient, without injury to the target artery. The caval-aortic tract was eventually closed with an occluder device. Histopathology of the aspirate revealed a malignant spindle-cell mesenchymal neoplasm consistent with intimal sarcoma. Staging subsequently demonstrated metastatic disease, and the patient proceeded to covered-stent maintenance of subclavian patency and first-line systemic chemotherapy. The patient is undergoing chemotherapy at 7-month follow-up, but palliation is being considered due to disease progression. Conclusions: Transcaval delivery of a large-bore aspiration system (AngioVac) is a feasible strategy to achieve both flow restoration and diagnostic tissue sampling when conventional arterial access is unavailable. Intimal sarcoma should be considered when arterial "thrombus" fails to respond to anticoagulation, particularly alongside constitutional symptoms.

Pleomorphism in cells encompasses a variety of morphological features, such as heterogeneity in the size and shape of cells and nuclei, irregularity of the nuclear membrane, hyperchromasia, and peculiarities of cell organelles. Pleomorphism in mammalian cells is associated with genetically unstable neoplasms and is frequently accompanied by high rates of proliferation and low differentiation status. Among soft tissue sarcomas, a group of tumors characterized by the pleomorphic phenotype can be distinguished. Pleomorphic soft tissue sarcomas are a rare, understudied group of soft tissue sarcomas with aggressive behavior, low survival rates, and high resistance to standard chemotherapy treatment. Knowledge of the mechanisms behind the pleomorphic features, common genetic and epigenetic alterations, and their association with aggressive tumorigenesis is essential for advancing patient care for this group of sarcomas. In this narrative review, we consolidate existing evidence concerning clinical features of pleomorphic sarcomas, their possible histogenesis, the common drivers and transcriptional networks, and the potentially available approaches for treatment.

Leiomyosarcoma (LMS) is a rare, aggressive soft-tissue sarcoma arising from smooth muscle cells. It has a high metastatic potential and limited therapeutic options. Despite advances in oncology, the molecular landscape of LMS remains incompletely understood, particularly regarding the genetic and epigenetic alterations that affect key signaling pathways. This review summarizes the current knowledge of mechanisms driving LMS pathogenesis, including somatic mutations in genes such as TP53 and RB1, chromosomal instability, dysfunction of DNA damage response and repair, aberrant DNA methylation, histone modifications, and non-coding RNAs. Emerging treatment strategies include inhibitors of PI3K/AKT/mTOR and CDK4/6 signaling, epigenetic drugs, immunotherapy, and combinations of these approaches. However, the coexistence of multiple genetic abnormalities complicates diagnosis, prognosis, and therapeutic selection. Companion diagnostic tools that test candidate therapies ex vivo or in vitro may help exclude potentially ineffective targeted treatments.

Background/Objectives: Osteosarcoma is a rare malignancy and the most common primary malignant bone tumor. Metastases commonly affect the lungs and are associated with reduced life expectancy. Calcifications can be present within a metastatic nodule at baseline or can appear during follow-up. We aimed to assess the clinical significance of calcifications in lung metastases, particularly in relation to radiological pattern, histopathological subtype, and treatment response. Methods: A retrospective cohort of patients with osteosarcoma and lung metastases at diagnosis was evaluated for the period 2000-2018. The presence of calcifications inside pulmonary lesions on baseline lung CT and/or follow-up was assessed and recorded. Radiological data were then checked against histopathological data (i.e., osteosarcoma subtypes and chemotherapy response with necrosis percentage) and the radiological pattern of the primary tumor (i.e., osteolytic, sclerotic, or mixed pattern). Results: Of a cohort of 92 patients, 14 were excluded due to having no baseline or follow-up chest CT. Of the 78 patients with an osteosarcoma diagnosis, lung metastases at diagnosis, and chest CT who were enrolled (42 men and 36 women; mean age: 23.8 years [range, 6-73 years]), 70 (89.7%) had a baseline imaging study of the primary tumor (osteosarcoma). The presence of calcifications in lung metastases at both baseline and follow-up was significantly associated with the radiological pattern of the primary lesion (p < 0.0001). Calcifications were not present in the lung metastases of any of the 18 patients (0%) with a lytic radiological pattern at any stage, whereas all 32 patients (100%) with a purely sclerotic pattern had calcifications within lung metastases at baseline or during follow-up; of the 20 patients with a mixed radiological pattern, 11 (55%) had no calcifications and 9 (45.0%) had detectable calcifications. No statistically significant association was found between histopathological subtype and calcification. Osteoblastic osteosarcoma was more frequently associated with calcification (66.0%). During induction chemotherapy, five poor responders and three good responders (necrosis > 90%) developed calcifications (p = 0.72; OR = 0.67; 95% CI, 0.10-3.86). Conclusions: In patients with osteosarcoma, calcifications within pulmonary metastases are strongly associated with the radiological pattern of the primary tumor, and this association is greatest for a pure sclerotic pattern, followed by the mixed one. We found no statistically significant association between the occurrence of calcifications during follow-up and chemotherapy response measured by necrosis percentage of the surgical specimen in our limited cohort; further research is needed.

Background/Objectives: Total scapulectomy for malignant scapular tumors remains a major reconstructive challenge because resection removes the osseous framework, muscular insertions, and biomechanical support required for shoulder function. Patient-specific three-dimensional (3D)-printed implants may improve anatomical reconstruction, but the indications and surgical principles underlying successful total scapular replacement remain poorly defined. Methods: This retrospective single-center case series included the first three consecutive patients who underwent total scapulectomy followed by immediate reconstruction using a patient-specific 3D-printed scapular prosthesis between January 2024 and December 2025. Clinical, radiographic, oncological, and functional outcomes were reviewed. Functional outcome was assessed using the Musculoskeletal Tumor Society (MSTS) score and active shoulder range of motion. Results: The cohort included two women and one man with a median age of 53 years (range, 43-58 years). Diagnoses were chondrosarcoma in two patients and osteosarcoma in one. All tumors were Enneking stage IIB. Negative margins were achieved in all patients, and the axillary nerve and principal shoulder-girdle stabilizers were preserved in every case. Median follow-up was 13 months (range, 12-27 months). At latest follow-up, two patients had no evidence of disease and one was alive with disease after developing pulmonary metastases. The median MSTS score was 25/30 (range, 21-26). Median active elbow flexion, abduction, and forward flexion measured 88°, 80°, and 80°, respectively. Two patients experienced complications: one clavicular fracture and one aseptic wound dehiscence; neither resulted in implant failure or required revision of the reconstruction. Conclusions: Patient-specific total scapular reconstruction may provide satisfactory early radiographic and functional outcomes in carefully selected patients, although outcomes remain variable depending on individual patient and tumor characteristics. Implant design, patient selection, preservation of the axillary nerve and viable innervated shoulder-girdle musculature, and soft-tissue reconstruction should be considered complementary components of this reconstructive strategy.

Primary chondrosarcoma of the sternum is a rare malignancy whose anatomical location can create major diagnostic, resection, and reconstruction challenges. We report a 62-year-old man with severe obesity and a heavy smoking history who presented with a progressively enlarging, painful sternal swelling. Preoperative imaging conducted via computed tomography and positron emission tomography-computed tomography demonstrated a large heterogeneous mass at the anterior thoracoabdominal junction infiltrating the xiphoid process. CT-guided biopsy established grade III chondrosarcoma. Because of the tumor's size, location, and infiltrative features, bilateral transverse thoraco-sternotomy ("Clamshell" Procedure) was performed. "En bloc" resection included the middle and lower sternum, involved soft tissues and adjacent costal arches, followed by prosthetic synthetic polypropylene mesh reconstruction. The final pathology documented tumor-free examined margins (R0), with an approximately 10 mm closest reported clearance. The postoperative course was prolonged and complex. The patient required 18 days of intensive care and tracheostomy on postoperative day 8 because of delayed awakening and intermittent oxygen desaturation. Wound dehiscence necessitated surgical revisions on postoperative days 29 and 44; during the second revision, the infected mesh was removed. The tracheostomy was removed on day 64, and the patient was discharged in a stable condition two days later. This case demonstrates that extensive open approaches remain indispensable for selected chest wall malignancies. It also emphasizes the importance of coordinated multidisciplinary perioperative care from diagnosis through recovery, while illustrating how reconstructive resources, patient risk, and infection can determine the procedure's outcome.

Background/Objectives: Myxofibrosarcoma (MFS) shows infiltrative fascial extensions that complicate margin achievement and drive local recurrence. We evaluated whether intraoperative ultrasound guidance improves negative margin achievement and oncological outcomes compared with conventional excision. Methods: In this retrospective cohort study at a single tertiary referral center, patients with MFS underwent conventional excision (2008-2013; n = 15) or ultrasound-guided excision (2014-2024; n = 50; primary comparative analysis n = 47 after excluding three patients). The primary outcome was negative margin achievement; secondary outcomes were overall survival (OS), local recurrence-free survival (LRFS), and distant metastasis-free survival (DMFS). Exploratory matching-adjusted indirect comparisons (MAICs) were performed against seven published international MFS cohorts. Results: Overall R0 (negative) margin rates did not differ between cohorts (97.9% vs. 93.3%; p = 0.428). Among R0 margins, however, a wide clearance (R0-wide, ≥1 mm) was more frequent in the US-guided cohort, whereas R0-close (<1 mm) margins predominated after conventional excision (R0-wide 83.0% vs. 46.7%; odds ratio 5.38, 95% CI 1.30-23.73; p = 0.014). Median follow-up was 49 months; five-year OS, LRFS, and DMFS were 97.5%, 94.3%, and 83.7%. In the internal historical comparison, LRFS was directionally higher with ultrasound guidance (94.3% vs. 68.2%; HR 0.26; p = 0.059). In MAICs, LRFS favored the US-guided cohort in all five comparisons and OS in two of four. Conclusions: Intraoperative ultrasound guidance was associated with a higher rate of wide (R0-wide, ≥1 mm) negative margins and favorable local disease control in MFS; whether wider microscopic clearance itself improves local control requires prospective multicenter evaluation.