Management of bone disease with concurrent chimeric antigen receptor T-cell therapy for multiple myeloma.

In the intricate landscape of multiple myeloma, a hematologic malignancy of plasma cells, bone disease presents a pivotal and often debilitating complication. The emergence of Chimeric Antigen Receptor T-cell (CAR-T) therapy has marked a pivotal shift in the therapeutic landscape, offering novel avenues for the management of MM, particularly for those with relapsed or refractory disease. This innovative treatment modality not only targets malignant cells with precision but also influences the bone microenvironment, presenting both challenges and opportunities in patient care. In this comprehensive review, we aim to examine the multifaceted aspects of bone disease in patients with multiple myeloma and concurrent CAR-T therapy, highlighting its clinical ramifications and the latest advancements in diagnostic modalities and therapeutic interventions. The article aims to synthesize current understanding of the interplay between myeloma cells, CAR-T cells, and the bone microenvironment in the context of current treatment strategies in this challenging and unique patient population.

Limb Amputations in Cancer: Modern Perspectives, Outcomes, and Alternatives.

PURPOSE OF REVIEW: This review summarizes current findings regarding limb amputation within the context of cancer, especially in osteosarcomas and other bony malignancies. We seek to answer the question of how amputation is utilized in the contemporary management of cancer as well as explore current advances in limb-sparing techniques. RECENT FINDINGS: The latest research on amputation has been sparse given its extensive history and application. However, new research has shown that rotationplasty, osseointegration, targeted muscle reinnervation (TMR), and regenerative peripheral nerve interfaces (RPNI) can provide patients with better functional outcomes than traditional amputation. While limb-sparing surgeries are the mainstay for managing musculoskeletal malignancies, limb amputation is useful as a palliative technique or as a primary treatment modality for more complex cancers. Currently, rotationplasty and osseointegration have been valuable limb-sparing techniques with osseointegration continuing to develop in recent years. TMR and RPNI have also been of interest in the modern management of patients requiring full or partial amputations, allowing for better control over myoelectric prostheses.

Outcomes and Complications of Pelvic Chondrosarcomas Treated Using Navigation Guidance and Multidisciplinary Approach: Is the Tumor Volume a Prognostic Factor?

(1) Background: Pelvic Chondrosarcomas (CS) have a poor prognosis. The grade is the most important survival predictor; other factors are periacetabular location and Dedifferentiated CS subtype. The aim of the study is to investigate a series of CS of the pelvis, to analyze the prognostic factors that affect outcomes and to demonstrate how the use of intraoperative navigation can reduce the complications without worse outcomes. (2) Methods: Retrospective study on 35 patients (21 M, 14 F), median age at surgery 54 years (IQR 41−65), with pelvic CS, treated with hemipelvectomy under navigation guidance. (3) Results: 30 high-grade CS and 5 low-grade CS; mean follow-up 51.4 months. There was a positive linear correlation between the tumor volume and the presence of local recurrence at follow-up. The mean survival time of patients with larger chondrosarcoma volume was lower, but not significantly so. Lower MSTS score was associated with significantly lower survival time (p < 0.001). (4) Conclusion: in this series overall survival, LR and distant metastasis were comparable with recent literature, while complication rate was lower compared to similar series without the use of navigation. There was a correlation between tumor volume and local recurrence rate but not with the presence of metastasis at follow up.

Osteosarcoma: An Evolving Understanding of a Complex Disease.

Osteosarcoma is the most common primary bone sarcoma and affects both children and adults. The cornerstone of treatment for patients with localized and oligometastatic disease remains neoadjuvant chemotherapy, surgical resection of all sites of disease, followed by adjuvant chemotherapy. This approach is associated with up to an 80% 5-year survival. However, survival of patients with metastatic disease remains poor, and overall, osteosarcoma remains a challenging disease to treat. Advances in the understanding of molecular drivers of the disease, identification of poor prognostic factors, development of risk-stratified treatment protocols, successful completion of large collaborative trials, and surgical advances have laid the ground work for progress. Advances in computer navigation, implant design, and surgical techniques have allowed surgeons to improve patients' physical functional without sacrificing oncologic outcomes. Future goals include identifying effective risk stratification algorithms which minimize patient toxicity while maximizing oncologic outcomes and continuing to improve the durability, function, and patient acceptance of oncologic reconstructions.

Pediatric Tumor Management: Current and Controversial.

Bone and soft-tissue tumors are common in the pediatric population. It is important to be familiar with the appropriate workup, principles of biopsy, differences between unicameral and aneurysmal bone cysts, and principles of managing pathologic fractures in children. The management approach to pediatric soft-tissue masses and some of the recent advances in the field warrant discussion.

Do children and adolescents with completely resected alveolar rhabdomyosarcoma require adjuvant radiation? A report from the Children's Oncology Group.

BACKGROUND: The role of adjuvant radiotherapy (RT) remains unclear in patients with localized, completely resected (group I) alveolar rhabdomyosarcoma (ARMS). PROCEDURE: Patients with group I ARMS enrolled on any one of three prior Children's Oncology Group (COG) clinical trials (D9602, D9803, or ARST0531) were analyzed. All patients received systemic chemotherapy and 36 Gy adjuvant RT (if given) to the primary site at week 12 or week 4 for D9602/D9803 and ARST0531, respectively. RESULTS: Thirty-six patients with group I ARMS were treated on D9602 (n = 6), D9803 (n = 17), or ARST0531 (n = 13), of whom 24 (67%) were male. The median age was 4.1 years (range, 0.8-45.8). Twenty (56%) patients had an unfavorable primary site, and 10 (28%) had tumors > 5 cm. FOXO1-fusion status was negative, positive, and unknown in 10 (28%), 15 (42%), and 11 (30%) tumors, respectively. Twenty-two (61%) patients received RT. Overall, the four-year event-free survival (EFS) and overall survival (OS) were 70.8% and 88.3%, respectively. Patients with FOXO1 positivity who received RT had superior EFS compared with those who did not (77.8% vs 16.7%; P = 0.03). Among 10 patients who were FOXO1 negative, the outcome was similar with or without RT. CONCLUSIONS: Although limited by a small sample size, data from this study support the routine use of adjuvant RT in patients with FOXO1-positive disease even after complete resection. Additionally, omitting adjuvant RT is rational for patients with FOXO1-negative ARMS and will be prospectively investigated in the current COG trial ARST1431.

Surgical and Functional Outcomes After Limb-Preservation Surgery for Tumor in Pediatric Patients: A Systematic Review.

BACKGROUND: Limb-salvage surgery and segmental reconstruction for the treatment of lower extremity osseous tumors in the pediatric population have been described in the literature, but there is little consensus regarding the optimal surgical treatment for this patient population. METHODS: A systematic review of the literature was performed to identify studies focusing on limb-salvage procedures in pediatric patients who were managed with one of three reconstructions with use of a metallic endoprosthesis, allograft, or allograft-prosthesis composite. Data were segregated according to the excised and reconstructed anatomical location (proximal part of the femur, total femur, distal part of the femur, proximal part of the tibia) and were collated to assess modes of failure and functional outcomes of each reconstruction type for each anatomic location. RESULTS: Sixty articles met the inclusion criteria; all were Level-IV evidence, primarily consisting of small, retrospective case series. Infection was a primary mode of failure across all reconstruction types and locations, whereas allograft reconstructions were susceptible to structural failure as well. The rate of failure in the pediatric population correlated well with previously published results for adults. The incidence of subsequent amputation was lower in the pediatric population (5.2%) than has been reported in adults (9.5%) (p = 0.013). Meaningful growth of expandable metallic endoprostheses was reported in the literature, with an overall rate of leg-length discrepancy of 13.4% being noted at the time of the latest follow-up. The Musculoskeletal Tumor Society (MSTS) questionnaire was the most consistently used outcome measure in the literature, with average scores ranging from 71.0% to 86.8%, depending on reconstruction type and anatomic location. CONCLUSIONS: The current state of the literature detailing the surgical and functional outcomes of segmental reconstruction for the treatment of pediatric bone tumors is limited to Level-IV evidence and is complicated by under-segregation of the data by age and anatomical location of the reconstruction. Despite these limitations, pediatric limb-salvage surgery demonstrates satisfactory initial surgical and functional outcomes. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Recurrence and survival analysis of resected soft tissue sarcomas of pelvic retroperitoneal structures.

BACKGROUND: The purpose is to determine the clinicopathologic factors related to survival and recurrence of primary resected pelvic soft tissue sarcomas (STS). METHODS: Demographic/clinical variables were recorded. RESULTS: Thirty-five pts were identified. Median follow-up was 24.2 months. There were 23 (65.7%) high/intermediate-grade and 12 (34.3%) low-grade tumors included in the final analysis. Eight patients (22.9%) received neoadjuvant therapy. Margins were grossly negative in 27 (77.1%, 17-R0, 10-R1) and grossly positive (R2) in 8 (22.9%). Adjuvant therapy was used in 13 patients (37.1%). The 2- and 3-year RFS was 56.5% and 51.3%, with 14 patients recurring at a median time of 16 months (6-local, 8-distant). All distant recurrences were in high-grade tumors. There were no differences in RFS for margins (R0 vs. R1), neoadjuvant/adjuvant therapy, size (≥10 vs. <10 cm) or gender. High/intermediate-grade tumors had worse RFS (P < 0.008). The 2- and 3-year OS was 80.9%. OS was improved for R0/R1 resection (P < 0.001). Resection to R0/R1 margin was a significant predictor of improved OS (P = 0.001). CONCLUSIONS: High/intermediate-grade lesions were associated with worse OS and RFS. Resection to gross negative margins was the only independent predictor of OS. Adjuvant therapy may be reserved for high-grade lesions due to increased metastatic potential. J

Chondroblastoma of bone in the extremities: a multicenter retrospective study.

BACKGROUND: Chondroblastoma is a rare benign cartilage tumor that commonly occurs in children and adolescents. This study was designed to review the epidemiologic characteristics and outcomes of surgical management in a large series of patients with extremity chondroblastoma. METHODS: We performed a multicenter retrospective analysis of 199 patients with extremity chondroblastoma. Clinical data, radiographic images, histological findings, treatment, and outcome were analyzed. RESULTS: There were 145 male patients and fifty-four female patients with a mean age of 18.0 years. The most commonly involved bone was the proximal part of the tibia (fifty-five patients [27.6%]), followed by the proximal part of the femur (fifty-two patients [26.1%]) and the distal part of the femur (thirty-eight patients [19.1%]). Prior to presentation, 73.4% (146 of 199 patients) experienced pain. The mean duration of pain and other symptoms was 8.7 months. The physis was open in 25.7%, it was closing in 22.2%, and it was closed in 52.1% of the patients at the time of presentation. One hundred and twenty-six patients had at least twenty-four months of follow-up; their mean follow-up duration was 62.1 months (range, twenty-four to 190 months). Initial treatment was curettage for 119 patients (94.4%) and en bloc resection for seven patients (5.6%). The local recurrence rate was 5.0% after curettage and 0% after resection. The only significant factor related to recurrence was the location of the lesion in the proximal part of the humerus (p = 0.001). CONCLUSIONS: Chondroblastoma occurs most frequently in the proximal part of the tibia and the proximal part of the femur with significant male predilection. In this series, recurrence was most frequent in the proximal part of the humerus. Our results suggest that curettage and bone-grafting provide favorable local control and satisfactory functional outcome for patients with this disease. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

What are the results using the modified trapdoor procedure to treat chondroblastoma of the femoral head?

BACKGROUND: Treatment of chondroblastoma in the femoral head is challenging owing to the particular location and its aggressive nature. There is little published information to guide the surgeon regarding the appropriate approach to treating a chondroblastoma in this location. We developed a modified trapdoor procedure to address this issue. The primary modification is that the window surface of the femoral head is covered by the ligamentum teres rather than cartilage as in the traditional procedure. QUESTIONS/PURPOSES: We assessed (1) the clinical presentation of chondroblastoma of the femoral head and treatment results with the modified trapdoor procedure in terms of (2) the frequency of local recurrence, (3) complications, and (4) functional outcomes using the Musculoskeletal Tumor Society (MSTS) score. METHODS: Between 1999 and 2010, we treated 14 patients for chondroblastoma of the femoral head. All patients received the modified trapdoor procedure. Of those, 13 were available for followup at a minimum of 36 months (mean, 66 months; range, 36-117 months) and one patient was lost to followup. There were nine males and four females, with a mean age of 18 years (range, 9-29 years). Clinical features were ascertained by chart and radiographic review, and recurrence, complications, and functional outcomes (MSTS score) were recorded from chart review. Patterns of bone destruction were evaluated using the Lodwick classification, which ranges from IA (geographic appearance with sclerotic rim) to III (permeative appearance). RESULTS: The symptoms at diagnosis were pain in nine patients and discomfort in four. The mean duration of symptom was 11 months (range, 1-36 months). The physis was open in two patients, closing in one, and closed in 10. The patterns of bone destruction were evaluated as Lodwick Class IA in six patients, Lodwick Class IB in five, and Lodwick Class IC in two. At latest followup, no local recurrence was observed. Two patients had postoperative complications. One had avascular necrosis of the femoral head and was treated with prosthesis replacement. The other had asymptomatic heterotopic ossification in the surgical field. The mean MSTS score was 29.6 (range, 28-30). CONCLUSIONS: Based on this small series, we believe our modified trapdoor procedure is a safe, effective means of treating a chondroblastoma in the femoral head, but additional clinical evaluation with more patients is necessary to confirm our findings. LEVEL OF EVIDENCE: Level IV, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence.

Outcome of lower-limb preservation with an expandable endoprosthesis after bone tumor resection in children.

BACKGROUND: The optimal treatment of malignant pediatric lower-extremity bone tumors is controversial. Expandable endoprostheses allow limb preservation, but the revision rate and limited function are considered barriers to their use. This study investigated the functional, emotional, and oncologic outcomes of thirty-eight patients treated with an expandable endoprosthesis. METHODS: A retrospective chart review was performed, and surviving patients were asked to complete the Musculoskeletal Tumor Society (MSTS) outcomes instrument and the Pediatric Outcomes Data Collection Instrument (PODCI). Additional data including the range of hip and knee motion, limb-length discrepancy, and total lengthening were also obtained. RESULTS: Thirty-eight patients were treated with an expandable endoprosthesis, and twenty-six of these patients were alive at the time of the study. The mean global MSTS score was 26.1, and the mean global PODCI score was 85.8. The mean emotional acceptance and happiness subscores were high. The mean sagittal-plane hip motion in patients who had undergone replacement of the proximal aspect of the femur was 103°. The mean knee motion in patients who had undergone replacement of the proximal aspect of the femur, the distal aspect of the femur, or the proximal aspect of the tibia was 127°, 97°, and 107°, respectively. The mean lengthening at the time of skeletal maturity was 4.5 cm, and the mean limb-length discrepancy was 0.7 cm. Forty-two percent of the patients experienced complications, with ten patients requiring prosthesis revision and two of these patients requiring amputation. CONCLUSIONS: Current technology does not offer a single best reconstruction option for children. Previous studies and the present series have indicated that physical and emotional functioning in patients treated with an expandable endoprosthesis are good but that complication rates remain high. Amputation and rotationplasty are alternative treatments if patients and their families are amenable to these procedures. The literature supports no single superior treatment among these three options with regard to physical or emotional health.