A Case Presentation of a Rare Pelvic Interdigitating Dendritic Cell Sarcoma

Sarcoma is a rare type of cancer that arises from connective tissue. Interdigitating dendritic cell sarcoma (IDCS) is a rare neoplasm of dendritic cell origin. IDCS arises from interdigitating dendritic cells found in the T-cell regions of secondary lymphoid tissues. Due to the rare nature of IDCS diagnosis, management can be difficult. Often, the diagnosis is delayed due to a lack of symptoms and signs. Here, we describe a case of a 34-year-old female patient who presented with an incidental finding of a left sidewall pelvic mass later to be confirmed on biopsy as an IDCS.

Pragmatic, Prospective Comparative Effectiveness Trial of Carbon Ion Therapy, Surgery, and Proton Therapy for the Management of Pelvic Sarcomas (Soft Tissue/Bone) Involving the Bone: The PROSPER Study Rationale and Design

Surgical treatment of pelvic sarcoma involving the bone is the standard of care but is associated with several sequelae and reduced functional quality of life (QOL). Treatment with photon and proton radiotherapy is associated with relapse. Carbon ion radiotherapy (CIRT) may reduce both relapse rates and treatment sequelae. The PROSPER study is a tricontinental, nonrandomized, prospective, three-arm, pragmatic trial evaluating treatments of pelvic sarcoma involving the bone. Patients aged at least 15 years are eligible for inclusion. Participants must have an Eastern Cooperative Oncology Group Performance Status score of two or less, newly diagnosed disease, and histopathologic confirmation of pelvic chordoma, chondrosarcoma, osteosarcoma, Ewing sarcoma with bone involvement, rhabdomyosarcoma (RMS) with bone involvement, or non-RMS soft tissue sarcoma with bone involvement. Treatment arms include (1) CIRT (n = 30) delivered in Europe and Asia, (2) surgical treatment with or without adjuvant radiotherapy (n = 30), and (3) proton therapy (n = 30). Arms two and three will be conducted at Mayo Clinic campuses in Arizona, Florida, and Minnesota. The primary end point is to compare the 1-year change in functional QOL between CIRT and surgical treatment. Additional comparisons among the three arms will be made between treatment sequelae, local control, and other QOL measures.

A computational method for estimating trunk muscle activations during gait using lower extremity muscle synergies

One of the surgical treatments for pelvic sarcoma is the restoration of hip function with a custom pelvic prosthesis after cancerous tumor removal. The orthopedic oncologist and orthopedic implant company must make numerous often subjective decisions regarding the design of the pelvic surgery and custom pelvic prosthesis. Using personalized musculoskeletal computer models to predict post-surgery walking function and custom pelvic prosthesis loading is an emerging method for making surgical and custom prosthesis design decisions in a more objective manner. Such predictions would necessitate the estimation of forces generated by muscles spanning the lower trunk and all joints of the lower extremities. However, estimating trunk and leg muscle forces simultaneously during walking based on electromyography (EMG) data remains challenging due to the limited number of EMG channels typically used for measurement of leg muscle activity. This study developed a computational method for estimating unmeasured trunk muscle activations during walking using lower extremity muscle synergies. To facilitate the calibration of an EMG-driven model and the estimation of leg muscle activations, EMG data were collected from each leg. Using non-negative matrix factorization, muscle synergies were extracted from activations of leg muscles. On the basis of previous studies, it was hypothesized that the time-varying synergy activations were shared between the trunk and leg muscles. The synergy weights required to reconstruct the trunk muscle activations were determined through optimization. The accuracy of the synergy-based method was dependent on the number of synergies and optimization formulation. With seven synergies and an increased level of activation minimization, the estimated activations of the erector spinae were strongly correlated with their measured activity. This study created a custom full-body model by combining two existing musculoskeletal models. The model was further modified and heavily personalized to represent various aspects of the pelvic sarcoma patient, all of which contributed to the estimation of trunk muscle activations. This proposed method can facilitate the prediction of post-surgery walking function and pelvic prosthesis loading, as well as provide objective evaluations for surgical and prosthesis design decisions.

Computational evaluation of psoas muscle influence on walking function following internal hemipelvectomy with reconstruction

An emerging option for internal hemipelvectomy surgery is custom prosthesis reconstruction. This option typically recapitulates the resected pelvic bony anatomy with the goal of maximizing post-surgery walking function while minimizing recovery time. However, the current custom prosthesis design process does not account for the patient's post-surgery prosthesis and bone loading patterns, nor can it predict how different surgical or rehabilitation decisions (e.g., retention or removal of the psoas muscle, strengthening the psoas) will affect prosthesis durability and post-surgery walking function. These factors may contribute to the high observed failure rate for custom pelvic prostheses, discouraging orthopedic oncologists from pursuing this valuable treatment option. One possibility for addressing this problem is to simulate the complex interaction between surgical and rehabilitation decisions, post-surgery walking function, and custom pelvic prosthesis design using patient-specific neuromusculoskeletal models. As a first step toward developing this capability, this study used a personalized neuromusculoskeletal model and direct collocation optimal control to predict the impact of ipsilateral psoas muscle strength on walking function following internal hemipelvectomy with custom prosthesis reconstruction. The influence of the psoas muscle was targeted since retention of this important muscle can be surgically demanding for certain tumors, requiring additional time in the operating room. The post-surgery walking predictions emulated the most common surgical scenario encountered at MD Anderson Cancer Center in Houston. Simulated post-surgery psoas strengths included 0% (removed), 50% (weakened), 100% (maintained), and 150% (strengthened) of the pre-surgery value. However, only the 100% and 150% cases successfully converged to a complete gait cycle. When post-surgery psoas strength was maintained, clinical gait features were predicted, including increased stance width, decreased stride length, and increased lumbar bending towards the operated side. Furthermore, when post-surgery psoas strength was increased, stance width and stride length returned to pre-surgery values. These results suggest that retention and strengthening of the psoas muscle on the operated side may be important for maximizing post-surgery walking function. If future studies can validate this computational approach using post-surgery experimental walking data, the approach may eventually influence surgical, rehabilitation, and custom prosthesis design decisions to meet the unique clinical needs of pelvic sarcoma patients.

Preoperative arterial embolization and wound complications after resection of malignant bone tumor in the pelvis: a nationwide database study

BACKGROUND

Massive intraoperative blood loss is common in pelvic malignant bone tumor surgery, and preoperative arterial embolization may be used in selected cases. Preoperative arterial embolization reportedly increases wound complications in pelvic fracture surgery, but little evidence is available regarding pelvic bone tumor surgery.

METHODS

Using a Japanese nationwide database (Diagnosis Procedure Combination database), we searched for patients who underwent pelvic malignant bone tumor surgery between July 2010 and March 2018. The primary endpoint was wound complications, defined as any wound requiring re-operation, negative pressure wound therapy or both. Univariate analyses (the chi-squared test for categorical variables, the unpaired t-test for continuous variables) and multivariate logistic regression analyses were performed to examine the association between preoperative arterial embolization and wound complications.

RESULTS

Among the 266 eligible patients, 43 (16%, 43/266) underwent embolization and 69 (26%, 69/266) developed wound complications. In the univariate analyses, preoperative arterial embolization (P < 0.001), duration of anesthesia (P < 0.001), the volume of blood transfusion (P < 0.001) and duration of indwelling drain tube (P < 0.001) were associated with wound complications. In the multivariate logistic regression analysis, preoperative arterial embolization was significantly associated with wound complications (odds ratio, 3.92; 95% confidence interval, 1.80-8.56; P = 0.001).

CONCLUSIONS

Preoperative arterial embolization may be associated with increased wound complications after pelvic malignant tumor surgery.

Surgical navigation for challenging recurrent or pretreated intra-abdominal and pelvic soft tissue sarcomas

BACKGROUND

This study assessed whether electromagnetic navigation can be of added value during resection of recurrent or post-therapy intra-abdominal/pelvic soft tissue sarcomas (STS) in challenging locations.

MATERIALS AND METHODS

Patients were included in a prospective navigation study. A pre-operatively 3D roadmap was made and tracked using electromagnetic reference markers. During the operation, an electromagnetic pointer was used for the localization of the tumor/critical anatomical structures. The primary endpoint was feasibility, secondary outcomes were safety and usability.

RESULTS

Nine patients with a total of 12 tumors were included, 7 patients with locally recurrent sarcoma. Three patients received neoadjuvant radiotherapy and three other patients received neoadjuvant systemic treatment. The median tumor size was 4.6 cm (2.4-10.4). The majority of distances from tumor to critical anatomical structures was <0.5 cm. The tumors were localized using the navigation system without technical or safety issues. Despite the challenging nature of these resections, 89% were R0 resections, with a median blood loss of 100 ml (20-1050) and one incident of vascular damage. Based on the survey, surgeons stated navigation resulted in shorter surgery time and made the resections easier.

CONCLUSION

Electromagnetic navigation facilitates resections of challenging lower intra-abdominal/pelvic STS and might be of added value.

Pelvic Radiation-Induced Sarcoma With Rhabdomyoblastic Differentiation Following Treatment of Cervical Cancer

Radiation-induced sarcomas (RIS) are a rare long-term complication of radiation therapy, with a reported incidence of 2.5-5.5%. They usually develop several years following exposure to radiotherapy. The most common reported subtypes are undifferentiated pleomorphic sarcoma, angiosarcoma, and leiomyosarcoma. Breast cancer is the most common primary malignancy preceding RIS, followed by uterine cervical carcinoma. Only a few cases of RIS with rhabdomyoblastic differentiation have been reported in the literature, usually following the treatment of retinoblastoma. Herein, we report a rare case of RIS with rhabdomyoblastic differentiation in the pelvic region developing 12 years after cervical cancer radiation therapy.

Intra-articular Partial Acetabular Resection and Allograft Reconstruction for Synovial Sarcoma

Introduction:

The aim of this case report is to present an option of reconstruction in tumors involving the posterior wall and column of the acetabulum with sparing of the anterior column and the weight-bearing dome.

Case Report:

We are reporting a case of a 25-year-old female with histopathologically proven synovial sarcoma involving the left inferior pubic ramus, ischium, and posterior wall of the acetabulum, along with a large soft-tissue extension in the posterior and medial thigh. Wide local excision involving partial acetabular resection and reconstruction using a femoral head allograft was carried out. The patient was allowed full weight-bearing mobilization after 6 weeks. At 3 months’ follow-up, the patient was able to walk without support and was able to do active straight leg raising. There were no radiological signs of joint degeneration at the 12-month follow-up.

Conclusion:

Reconstruction with non-articular femoral head allograft can be a viable alternative after resection of tumor involving acetabulum. This procedure is expected to support the hip joint and restore function in the short term and recreate bone stock for future arthroplasty if the need arises.

Radiation-associated sarcoma after recurrent colorectal primary tumor: A complex surgical case

Radiation associated sarcoma is a significant consequence of cancer therapy. Incidence of radiation associated sarcoma correlates with overall radiotherapy exposure. Prognosis is generally poor with 5 year survival rates lower than that for spontaneously occurring sarcomas. Surgical management presents many challenges including having to work in irradiated tissue planes while trying to achieve negative margins. We present a patient with a rare radiation associated pelvic sarcoma whose course illustrates the complexity of this problem.

Rehabilitation considerations for a patient with external hemipelvectomy and hemisacrectomy for recurrent soft tissue pelvic sarcoma: a case report

BACKGROUND AND PURPOSE

External hemipelvectomy (EHP) is an uncommon procedure involving surgical amputation of the lower extremity and hemipelvis. Soft tissue sarcomas of the pelvis are rare and accompanied by a high risk of disease progression after surgical intervention. The purpose of this case report is to describe the rehabilitation considerations and importance of interdisciplinary collaboration to achieve functional goals to allow discharge with improved independence and decreased caregiver burden.

CASE DESCRIPTION

A 58-year-old Caucasian male patient underwent a hemipelvectomy and hemisacrectomy for treatment of a recurrent pelvic soft tissue sarcoma following 4 months of bed confinement secondary to pain and weakness of the involved lower extremity. This report outlines the physical therapy interventions during 3 weeks of inpatient rehabilitation.

CONCLUSION

This case demonstrates that continuous interdisciplinary care of a complex patient with EHP and hemisacrectomy contributes to significant improvement in functional mobility exceeding prior level of function. This case is particularly interesting because in addition to having a rare diagnosis and undergoing an uncommon surgical procedure, this patient was confined to bed for 4 months prior to surgical intervention, and thus began rehabilitation with a baseline of limited functional mobility and high caregiver burden.