Multiple sporadic schwannomas in a previously radiated field.

Peripheral nerve sheath tumors are a heterogenous group of predominantly benign tumors of neurogenic origin that arise outside of the central nervous system and include schwannomas and neurofibromas. These tumors often occur sporadically, however multiple lesions are generally associated with genetic syndromes such as neurofibromatosis (type 1 and 2) and schwannomatosis, and occasionally these tumors and their malignant variations are associated with a history of radiation treatment. Multiple benign schwannomas in an irradiated field have seldom been reported in the literature. We describe a case of a 49-year-old male with a history of right sided irradiated testicular cancer who presented with 2 histologically confirmed benign schwannomas in the right pelvic wall and right psoas muscle.

Vimseltinib versus a placebo in patients with tenosynovial giant cell tumor: a plain language summary of the MOTION phase 3 trial.

WHAT IS THIS SUMMARY ABOUT?: This article presents a patient-friendly summary of the MOTION phase 3 clinical trial results, which were published in The Lancet in June 2024.The primary goal of the MOTION trial was to understand if treatment with a drug called vimseltinib shrank tumors more than a placebo in participants with symptomatic tenosynovial giant cell tumor, also known as TGCT, for which surgery was unlikely to provide benefit. A placebo is something that looks like the treatment being studied but does not contain any medicine.The MOTION trial compared the effects of vimseltinib versus a placebo using several different outcomes associated with TGCT. These outcomes included tumor size, active range of motion of the affected joint, and several patient-reported quality-of-life measures including physical function, stiffness, overall health, and pain. WHAT WERE THE MAIN CONCLUSIONS REPORTED BY THE RESEARCHERS?: The trial showed that more participants treated with vimseltinib experienced significant tumor shrinkage, as defined by a 30% or greater reduction in tumor size, compared with those receiving a placebo. Participants receiving vimseltinib had improved active range of motion, and they reported improved physical function, stiffness, overall health, and pain, regardless of the amount of tumor shrinkage, compared with participants receiving a placebo. Most side effects in participants treated with vimseltinib were not severe and were manageable. WHAT ARE THE KEY TAKEAWAYS?: Vimseltinib was better at shrinking tumors and improving active range of motion, stiffness, pain, and other health measures than the placebo for participants with TGCT. Vimseltinib has the potential to become a new treatment option for patients with TGCT for whom surgery may not provide benefit.

The landscape of drug sensitivity and resistance in sarcoma.

Sarcomas are rare malignancies with over 100 distinct histological subtypes. Their rarity and heterogeneity pose significant challenges to identifying effective therapies, and approved regimens show varied responses. Novel, personalized approaches to therapy are needed to improve patient outcomes. Patient-derived tumor organoids (PDTOs) model tumor behavior across an array of malignancies. We leverage PDTOs to characterize the landscape of drug resistance and sensitivity in sarcoma, collecting 194 specimens from 126 patients spanning 24 distinct sarcoma subtypes. Our high-throughput organoid screening pipeline tested single agents and combinations, with results available within a week from surgery. Drug sensitivity correlated with clinical features such as tumor subtype, treatment history, and disease trajectory. PDTO screening can facilitate optimal drug selection and mirror patient outcomes in sarcoma. We could identify at least one FDA-approved or NCCN-recommended effective regimen for 59% of the specimens, demonstrating the potential of our pipeline to provide actionable treatment information.

Early Complications of Planned Resection Versus Unplanned Excision of Sarcomas in the Distal Upper Extremity.

Purpose: Unplanned excisions are defined as excisions of malignant tumors performed without preoperative cross-sectional imaging or diagnostic biopsy, frequently resulting in residual disease and re-excision secondary to positive surgical margins. The purpose of this study was to compare the relative morbidity of planned versus unplanned upper-extremity sarcoma excisions. Methods: A single tertiary referral hospital pathology database was queried from January 2015 through 2022 for primary upper-extremity sarcomas (forearm, wrist, hand, and finger). Demographics, tumor features, survival characteristics, and outcomes were retrospectively reviewed. Results: Forty-two upper-extremity sarcoma patients were identified, two-thirds of whom had unplanned excisions. Those with unplanned excisions were more likely to be female (relative risk [RR]: 1.9; P = .002), undergo initial excision at a nonsarcoma center (RR: 14.0; P < .001), have masses distal to the forearm (RR: 1.6; P = .02), and have smaller masses (4.8 vs 7.4 cm, P = .03). 71.4% of tumors were high grade, and 60.7% less than 5 cm in size.Unplanned excisions had positive margins in 96.4% of cases and were more likely to undergo re-excision (odds ratio [OR]: 20.0; P = .001), more total resections (2.7 vs 1.4, P = .009), sacrifice of neurovascular structures (OR: 6.1; P = .04), adjuvant radiation therapy (OR: 4.5; P = .05), adjuvant systemic therapy (OR: 10.9; P = .03), or experience a complication (OR: 17.6; P = .002) at an average of 38.0 months of follow-up.Nearly half of all unplanned excision patients developed a local recurrence or metastatic disease. Six patients required an amputation versus one in the planned cohort (P = .17), and 26.5% of patients died at an average of 32.5 months from presentation. Conclusions: Distal upper-extremity sarcoma excisions are frequently unplanned, with high rates of morbidity compared with planned excisions. Surgeons should have a low threshold for cross-sectional imaging and core needle biopsy of atypical lesions, irrespective of size, with referral to a sarcoma center. Type of study/level of evidence: Prognostic IV.

Treatment of a Carpal Giant Cell Tumor of Bone With Curettage and Cemented Capitohamate Fusion.

Carpal giant cell tumor of bone spanning multiple bones is a rare condition. We present a case of a man in his fifth decade with wrist pain who was found to have giant cell tumor of bone involving his capitate and hamate bones. This condition was successfully treated with intralesional curettage, argon beam coagulation, chemical cauterization and a cemented limited carpal fusion with satisfactory outcomes and no recurrence at 1-year postoperative follow-up.

CSF1R Inhibition in Patients with Advanced Solid Tumors or Tenosynovial Giant Cell Tumor: A Phase I Study of Vimseltinib.

PURPOSE: Tenosynovial giant cell tumor (TGCT) is a locally aggressive neoplasm caused by dysregulation of the colony-stimulating factor 1 (CSF1) gene and overexpression of the CSF1 ligand. Surgery is the standard of care for most patients, but there are limited treatment options for patients with TGCT not amenable to surgery. This study evaluates vimseltinib, an investigational, oral, switch-control tyrosine kinase inhibitor designed to selectively and potently inhibit the CSF1 receptor. PATIENTS AND METHODS: This first-in-human, multicenter, open-label phase I/II study of vimseltinib in patients with malignant solid tumors (N = 37) or TGCT not amenable to surgery (N = 32) followed a pharmacologically guided 3 + 3 study design (NCT03069469). The primary objectives were to assess safety and tolerability, determine the recommended phase II dose, and characterize the pharmacokinetics; exploratory objectives included pharmacodynamics and efficacy. RESULTS: Vimseltinib was well tolerated; the majority of non-laboratory treatment-emergent adverse events were of grade 1/2 severity. There was no evidence of cholestatic hepatotoxicity or drug-induced liver injury. The recommended phase II dose was determined to be 30 mg twice weekly (no loading dose), and vimseltinib plasma exposure increased with the dose. In patients with TGCT, the median treatment duration was 25.1 months (range, 0.7-46.9), and the objective response rate as assessed by independent radiological review using RECIST version 1.1 was 72%. CONCLUSIONS: Vimseltinib demonstrated long-term tolerability, manageable safety, dose-dependent exposure, and robust antitumor activity in patients with TGCT not amenable to surgery.

Vimseltinib versus placebo for tenosynovial giant cell tumour (MOTION): a multicentre, randomised, double-blind, placebo-controlled, phase 3 trial.

BACKGROUND: Tenosynovial giant cell tumour (TGCT) is a locally aggressive neoplasm for which few systemic treatment options exist. This study evaluated the efficacy and safety of vimseltinib, an oral, switch-control, CSF1R inhibitor, in patients with symptomatic TGCT not amenable to surgery. METHODS: MOTION is a multicentre, randomised, double-blind, placebo-controlled, phase 3 trial done in 35 specialised hospitals in 13 countries. Eligible patients were adults (aged ≥18 years) with a histologically confirmed diagnosis of TGCT for which surgical resection could potentially worsen functional limitation or cause severe morbidity. Patients were randomly assigned (2:1) with interactive response technology to vimseltinib (30 mg orally twice weekly) or placebo, administrated in 28-day cycles for 24 weeks. Patients and site personnel were masked to treatment assignment until week 25, unless progressive disease was confirmed earlier. The primary endpoint was objective response rate by independent radiological review using Response Evaluation Criteria in Solid Tumors, version 1.1 (RECIST) at week 25 in the intention-to-treat population. Safety was assessed in all patients who received the study drug. The trial is registered with ClinicalTrials.gov, NCT05059262, and enrolment is complete. FINDINGS: Between Jan 21, 2022, and Feb 21, 2023, 123 patients were randomly assigned (83 to vimseltinib and 40 to placebo). 73 (59%) patients were female and 50 (41%) were male. Nine (11%) of 83 patients assigned to vimseltinib and five (13%) of 40 patients assigned to placebo discontinued treatment before week 25; one patient in the placebo group did not receive any study drug. Objective response rate per RECIST was 40% (33 of 83 patients) in the vimseltinib group vs 0% (none of 40) in the placebo group (difference 40% [95% CI 29-51]; p<0·0001). Most treatment-emergent adverse events (TEAEs) were grade 1 or 2; the only grade 3 or 4 TEAE that occurred in more than 5% of patients receiving vimseltinib was increased blood creatine phosphokinase (eight [10%] of 83). One patient in the vimseltinib group had a treatment-related serious TEAE of subcutaneous abscess. No evidence of cholestatic hepatotoxicity or drug-induced liver injury was noted. INTERPRETATION: Vimseltinib produced a significant objective response rate and clinically meaningful functional and symptomatic improvement in patients with TGCT, providing an effective treatment option for these patients. FUNDING: Deciphera Pharmaceuticals.

Antibiotic calcium sulphate beads lower the bacterial burden and prevent infection in a mouse model of periprosthetic joint infection.

Aims: Delayed postoperative inoculation of orthopaedic implants with persistent wound drainage or bacterial seeding of a haematoma can result in periprosthetic joint infection (PJI). The aim of this in vivo study was to compare the efficacy of vancomycin powder with vancomycin-eluting calcium sulphate beads in preventing PJI due to delayed inoculation. Methods: A mouse model of PJI of the knee was used. Mice were randomized into groups with intervention at the time of surgery (postoperative day (POD) 0): a sterile control (SC; n = 6); infected control (IC; n = 15); systemic vancomycin (SV; n = 9); vancomycin powder (VP; n = 21); and vancomycin bead (VB; n = 19) groups. Delayed inoculation was introduced during an arthrotomy on POD 7 with 1 × 105 colony-forming units (CFUs) of a bioluminescent strain of Staphylococcus aureus. The bacterial burden was monitored using bioluminescence in vivo. All mice were killed on POD 21. Implants and soft-tissue were harvested and sonicated for analysis of the CFUs. Results: The mean in vivo bioluminescence in the VB group was significantly lower on POD 8 and POD 10 compared with the other groups. There was a significant 1.3-log10 (95%) and 1.5-log10 (97%) reduction in mean soft-tissue CFUs in the VB group compared with the VP and IC groups (3.6 × 103 vs 7.0 × 104; p = 0.022; 3.6 × 103 vs 1.0 × 105; p = 0.007, respectively) at POD 21. There was a significant 1.6-log10 (98%) reduction in mean implant CFUs in the VB group compared with the IC group (1.3 × 100 vs 4.7 × 101, respectively; p = 0.038). Combined soft-tissue and implant infection was prevented in 10 of 19 mice (53%) in the VB group as opposed to 5 of 21 (24%) in the VP group, 3 of 15 (20%) in the IC group, and 0% in the SV group. Conclusion: In our in vivo mouse model, antibiotic-releasing calcium sulphate beads appeared to outperform vancomycin powder alone in lowering the bacterial burden and preventing soft-tissue and implant infections.

Controversies in orthopaedic oncology.

Chondrosarcoma is the second most common surgically treated primary bone sarcoma. Despite a large number of scientific papers in the literature, there is still significant controversy about diagnostics, treatment of the primary tumour, subtypes, and complications. Therefore, consensus on its day-to-day treatment decisions is needed. In January 2024, the Birmingham Orthopaedic Oncology Meeting (BOOM) attempted to gain global consensus from 300 delegates from over 50 countries. The meeting focused on these critical areas and aimed to generate consensus statements based on evidence amalgamation and expert opinion from diverse geographical regions. In parallel, periprosthetic joint infection (PJI) in oncological reconstructions poses unique challenges due to factors such as adjuvant treatments, large exposures, and the complexity of surgery. The meeting debated two-stage revisions, antibiotic prophylaxis, managing acute PJI in patients undergoing chemotherapy, and defining the best strategies for wound management and allograft reconstruction. The objectives of the meeting extended beyond resolving immediate controversies. It sought to foster global collaboration among specialists attending the meeting, and to encourage future research projects to address unsolved dilemmas. By highlighting areas of disagreement and promoting collaborative research endeavours, this initiative aims to enhance treatment standards and potentially improve outcomes for patients globally. This paper sets out some of the controversies and questions that were debated in the meeting.

Hip Preservation and Capanna Reconstruction for Pediatric Proximal Femur Ewing Sarcoma: A Report of 2 Cases.

CASE: This is a first report describing preservation of the femoral head by transcervical resection of proximal femoral Ewing sarcoma in 2 pediatric patients. A unique Capanna reconstruction supported joint salvage. At 1 year, Pediatric Outcomes Data Collection Instrument and Pediatric Toronto Extremity Salvage Score outcomes were excellent. Surveillance magnetic resonance imaging was without evidence of recurrence or impaired perfusion to the femoral head. CONCLUSION: We demonstrate the feasibility of hip joint preservation and maintenance of femoral head viability after transcervical resection of pediatric proximal femur bone sarcomas while preserving the medial circumflex femoral artery. This technique may be a preferred option over joint sacrifice and endoprosthetic replacement in young patients when tumor margins permit.

Are our actions matching our words? A review of trainee ethnic and gender diversity in orthopaedic surgery.

Background: There is a lack of physician ethnic and gender diversity amongst surgical specialties. This study analyzes the literature that promotes diversity amongst surgical trainees. Specifically, this study sought to answer (i) how the number of publications regarding diversity in orthopaedic surgery compares to other surgical specialties, (ii) how the number of publications amongst all surgical subspecialties trends over time and (iii) which specific topics regarding diversity are discussed in the surgical literature. Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were used to query articles from PubMed, Web of Science, Embase and the Cumulative Index to Nursing and Allied Health Literature. Broad inclusion criteria for both ethnic and gender diversity of any surgical specialty were utilized. Results: Our query resulted 1429 publications, of which 408 duplicates were removed, and 701 were excluded on title and abstract screening, leaving 320 to be included. The highest number of related publications was in orthopaedic surgery (n = 73) followed by general surgery (n = 56). Out of 320 total articles, 260 (81.3 %) were published after 2015, and 56 of 73 (76.7 %) orthopaedic-specific articles were published after 2015. Conclusion: Orthopaedic surgery published the most about ethnic and gender diversity, however, still remains one of the least diverse surgical specialties. With the recent increase in publications on diversity in surgical training, close attention should be paid to ethnic and gender diversity amongst surgical trainees over the coming years. Should diversity remain stagnant, diversification efforts may need to be restructured to achieve a diverse surgeon workforce. Key message: Orthopaedic surgery is the surgical subspecialty that publishes the most about trainee ethnic and gender diversity followed by general surgery. With most of this literature being published over the last eight years, it is imperative to pay close attention to the ethnic and gender landscape of the surgeon workforce over the coming years.

Active surveillance of diffuse-type tenosynovial giant cell tumors: A retrospective, multicenter cohort study.

BACKGROUND: Diffuse-type tenosynovial giant cell tumor (D-TGCT) is a mono-articular, soft-tissue tumor. Although it can behave locally aggressively, D-TGCT is a non-malignant disease. This is the first study describing the natural course of D-TGCT and evaluating active surveillance as possible treatment strategy. METHODS: This retrospective, multicenter study included therapy naïve patients with D-TGCT from eight sarcoma centers worldwide between 2000 and 2019. Patients initially managed by active surveillance following their first consultation were eligible. Data regarding the radiological and clinical course and subsequent treatments were collected. RESULTS: Sixty-one patients with primary D-TGCT were initially managed by active surveillance. Fifty-nine patients had an MRI performed around first consultation: D-TGCT was located intra-articular in most patients (n = 56; 95 %) and extra-articular in 14 cases (24 %). At baseline, osteoarthritis was observed in 13 patients (22 %) on MRI. Most of the patients' reported symptoms: pain (n = 43; 70 %), swelling (n = 33; 54 %). Eight patients (13 %) were asymptomatic. Follow-up data were available for 58 patients; the median follow-up was 28 months. Twenty-one patients (36 %) had radiological progression after 21 months (median). Eight of 45 patients (18 %) without osteoarthritis at baseline developed osteoarthritis during follow-up. Thirty-seven patients (64 %) did not clinically deteriorate during follow-up. Finally, eighteen patients (31 %) required a subsequent treatment. CONCLUSION: Active surveillance can be considered adequate for selected therapy naïve D-TGCT patients. Although follow-up data was limited, almost two-thirds of the patients remained progression-free, and 69 % did not need treatment during the follow-up period. However, one-fifth of patients developed secondary osteoarthritis. Prospective studies on active surveillance are warranted.

The MOTION study: a randomized, phase III study of vimseltinib for the treatment of tenosynovial giant cell tumor.

Tenosynovial giant cell tumor (TGCT) is a rare, locally aggressive neoplasm that occurs in the synovium of joints, bursae, or tendon sheaths and is caused by upregulation of the CSF1 gene. Vimseltinib is an oral switch-control tyrosine kinase inhibitor specifically designed to selectively and potently inhibit the CSF1 receptor. Here, we describe the rationale and design for the phase III MOTION trial (NCT05059262), which aims to evaluate the efficacy and safety of vimseltinib in participants with TGCT not amenable to surgical resection. In part 1, participants are randomized to receive vimseltinib 30 mg twice weekly or matching placebo for ≤24 weeks. Part 2 is a long-term treatment phase in which participants will receive open-label vimseltinib.

Tenosynovial giant cell tumor (or TGCT) is a rare, noncancerous tumor that grows in the soft tissue lining the spaces of joints and bursae (fluid-filled sacs that work to reduce friction in the joints). These tumors are linked to increased levels of a protein called CSF1. While this condition is typically treated with surgery, some patients may not be candidates for surgical removal of the tumor due to factors such as location or complexity of the tumor; therefore, drug treatments are needed to help these patients. Vimseltinib is an investigational oral drug specifically designed to inhibit the receptor to which the CSF1 protein binds. In this article, we describe the rationale and design for a phase III clinical trial that will test how well vimseltinib works in participants with TGCT who are not candidates for surgery. In the first part of the study, participants are randomly assigned to receive vimseltinib 30 mg twice weekly or a matching placebo (inactive substance) for up to 24 weeks. This first part is blinded, so participants will not know if they are receiving vimseltinib or the placebo. The second part of the study is a long-term treatment phase in which all participants will receive vimseltinib (unblinded). Clinical Trial Registration: NCT05059262 (ClinicalTrials.gov).

Thematic analysis of online discussion forums for soft tissue sarcomas.

BACKGROUND AND OBJECTIVES: As there is an increasing reliance on the internet for medical information, patients diagnosed with rare diseases have turned to online community forums to share information about their diagnoses. These forums help patients to gather and share information about their experience with disease. Additionally, these platforms enable patients to build unique connections based on their shared experiences. The objective of this study was to review shared posts in online community forums by individuals with soft tissue sarcomas to better understand commonly discussed themes. This information may improve the physicians' understanding of patients' concerns and feelings at the time of diagnosis and treatment. METHODS: We entered "sarcoma discussion forum" in search engines to identify internet discussion boards. Four major discussion forums were analyzed, and posts written between January 1, 2017 through May 1, 2022 addressing soft tissue sarcomas present in the upper and lower extremities were collected. Each post was analyzed by the two investigators in three steps (open coding, axial coding, and selective coding). RESULTS: A total of 506 posts were included in the final analysis. We used twenty-seven axial codes and four selective codes. Emotional Aspects/Connecting with Others was the most common theme (77 % of posts) followed by Information Support: Treatment (38 % of posts), Information Support: Diagnosis (24 % of posts) and Information Support: Recovery (21 % of posts). CONCLUSIONS: The most prevalent theme was centered on emotional aspects of these patients' journeys, highlighting the importance of providing resources to address emotional support for patients with soft tissue sarcoma and their families. LEVEL IV: Qualitative research study.

Arthroscopic debridement for acute hemorrhagic subacromial bursitis following COVID-19 vaccine administration: A case report.

The rapid rollout of vaccinations in response to the COVID-19 pandemic has led to their widespread distribution and administration throughout the world. The benefit of these vaccinations in preventing the spread of the disease and diminishing symptoms in patients who contract COVID-19 has been fervently studied and reported. While vaccinations remain an effective and generally safe method of limiting disease transmission and virus-related mortality, vaccine administration is not completely without risk. Shoulder injuries related to vaccine administration (SIRVA) have been described with previously available vaccines but have yet to be widely reported in the COVID-19 vaccination population. We present a case report of a young, high-functioning patient who presented with acute subacromial bursitis after COVID-19 vaccine administration due to improper vaccination technique. The patient was treated with arthroscopic shoulder surgery and had near immediate relief of shoulder symptoms.

Approach to the Treatment of Expansile Metacarpal Aneurysmal Bone Cysts: A Report of Two Cases.

The two cases presented demonstrate the management of aneurysmal bone cysts of the metacarpal, which destroyed the normal bone architecture. Treatment of both cases included wide resection and metacarpal reconstruction with an intercalary fibular allograft. Denosumab use contrasts these two cases and is helpful in reestablishment of a cortical rim for fixation in the absence of a 1-cm margin proximally or distally to preserve the native carpometacarpal and metacarpophalangeal joints. Surgical resection and allograft reconstruction is a viable treatment for expansile metacarpal aneurysmal bone cysts, and neoadjuvant denosumab has utility in creating an ossified margin for fixation.

Multimodal management of tenosynovial giant cell tumors (TGCT) in the landscape of new druggable targets.

Tenosynovial giant cell tumor (TGCT) is a rare, benign, locally aggressive synovial based neoplastic process that can result in functional debilitation and end-stage arthrtitis. Although surgical resection is the primary treatment modality, novel systemic therapies are emerging as part of the multimodal armamentarium for patients with unresectable or complex disease burden. This review discusses the pathogenesis of TGCT, potential druggable targets and therapeutic approaches. It also evaluates the safety and efficacy of different systemic therapies.

The microbial profile of infected endoprosthetic reconstructions after wide excision for patients with musculoskeletal tumors: A call for pathogen-based practices.

BACKGROUND AND OBJECTIVES: Periprosthetic infection is a devastating complication following endoprosthetic reconstruction. This study utilized a large database of endoprostheses to describe the incidence, risk factors, and microbial profile of such infections to better catalogue and understand these catastrophic events. METHODS: A retrospective review of endoprosthetic reconstructions for an oncologic indication from January 1, 1981 to December 31, 2020 was performed. Demographic, oncologic, procedural and outcome data was analyzed. Multivariable logistic regression was used to identify potential risk factors for infection with significance defined as p < 0.05. RESULTS: Forty four out of 712 (6.2%) reconstructions resulted in infection at a mean time of 39.9 ± 44.5 months. Revision surgery (odds ratio [OR] 6.14, p < 0.001) or having a postoperative wound complication (OR 7.67, p < 0.001) were significantly associated with infection. Staphylococcus aureus and Staphylococcus epidermidis were the most commonly cultured organisms at a rate of 34.1% (15/44) and 22.7% (10/44), respectively. Ten infections resulted in amputation; five due to antimicrobial-resistant infections and three due to polymicrobial infections. CONCLUSION: Understanding the microbial profile of patients undergoing endoprosthetic reconstruction is paramount. This study demonstrates a relatively high rate of polymicrobial and antibiotic-resistant infections that portend worse outcomes, thus suggesting that pathogen-specific infectious practices may be warranted. LEVEL OF EVIDENCE: Retrospective cohort study, level III.

Most Patients With Bone Sarcomas Seek Emotional Support and Information About Other Patients' Experiences: A Thematic Analysis.

BACKGROUND: Online discussion forums allow individuals who otherwise may be strangers to create a community where they can seek and share information. Patients with bone sarcomas and their support networks use discussion forums dedicated to cancer support. There is a paucity of published reports regarding the care experience of patients with bone sarcomas because studies on online discussion groups have primarily focused on some of the more common cancers, including breast and prostate cancer. Understanding commonly discussed themes among patients with bone sarcomas would allow treating physicians to have a better understanding of patient concerns when providing patient education and counseling. QUESTION/PURPOSE: We performed this study to review posts from bone sarcoma internet discussion boards to establish common themes related to the care experience of patients with sarcomas. METHODS: Online discussion forums were identified using the search term "sarcoma discussion forum." After identifying 12 websites, we excluded closed forum groups, websites with missing or invalid links to forums, and nonpublic forums, such as groups on Facebook. These websites include profiles and photos that are personal, and sufficient author anonymity could not be achieved for this study. Posts written between January 1, 2012, and May 1, 2022, posted on five discussion boards were reviewed and collected until we reached a point of data saturation in which we agreed that the collection of additional posts would not reveal new themes. Discussion threads were filtered to identify posts pertaining to the most common bone sarcomas: chondrosarcoma, Ewing sarcoma, and osteosarcoma. Grounded theory-the methodology of repeated analyses of qualitative data to identify recurring themes or concepts-was used to analyze posts. Caregiver posts were delineated from patient posts and categorized separately for subgroup analysis. Grounded theory, although a qualitative method, endeavors to integrate the strengths inherent in quantitative methods with qualitative approaches. Grounded theory categorizes words, language, and the meanings these imply and seeks to organize and reduce the data gathered into themes or essences, which, in turn, can be fed into descriptions, models, or theories. Our analysis used three reviews of text to assign and group codes based on repeating ideas or concepts. The first review (open coding) aims to assign codes based on the verbatim text included by the author to capture the specific thoughts and ideas of the post. The second review (axial coding) aims to consolidate the ideas of posts by applying broader concepts to each post. The third and final review (selective coding) aims to further consolidate the themes of each post by trying to embody the main message contained in a post. A total of 570 posts from 139 threads were collected and analyzed using grounded theory. Twenty-five axial codes and four selective codes were created. We defined data saturation by the absence of a new open code in the analysis of a block of 50 posts to ensure that signals of saturation were not accepted too early in the analysis. RESULTS: The four selective codes included emotional aspects or connecting with others, information support: diagnosis, information support: treatment, and information support: recovery. Of these four codes, emotional aspects and connecting with others was the most prevalent theme (78% [445 of 570] of posts) followed by information support: treatment (49% [282 of 570] of posts). Information support: diagnosis and information support: recovery were each captured in 15% of posts. CONCLUSION: Analysis of posts reveals that the two most common themes involve seeking out emotional support and information about the experiences of others with various treatment modalities. Although most of the posts we assessed contained experiential information and emotional support rather than directed medical advice, future studies should assess the accuracy of information shared among online sarcoma forums. CLINICAL RELEVANCE: Physicians caring for patients with sarcomas should not only address patient concerns related to medical care, but also provide emotional support directly and assist patients by providing resources to peer support outlets, including online discussion forums. Although we cannot ascertain the proportion of patients who use online sites given the anonymity of posts included, these findings suggest common experiential themes across patients with sarcomas outside their doctors' offices. It is important that providers be aware of reputable forums to provide as resources for their patients. The Musculoskeletal Tumor Society may further benefit from endorsing one or more of these forums and providing physician oversight to monitor misinformation.