Extracorporeal Irradiation Research Articles

Extracorporeal irradiation and reimplantation for bone sarcomas: Medium- and long-term oncologic and functional outcomes.

Extracorporeal irradiation and reimplantation for bone sarcomas: Medium- and long-term oncologic and functional outcomes.

Intra-operative extracorporeal irradiation of tumour-invaded craniotomy bone flap in meningioma: a case series

BackgroundExtracorporeal irradiation of tumorous calvaria (EITC) can be performed to restore function and form of the skull after resection of bone-invasive meningioma. We sought to examine the rate of tumour recurrence and other selected outcomes in patients undergoing meningioma resection and EITC.MethodsRetrospective single-centre study of adult patients undergoing meningioma resection and EITC between January 2015 and November 2022 at a tertiary neurosurgical centre. Patient demographics, surgery data, tumour data, use of adjuvant therapy, surgical complications, and tumour recurrences were collected.ResultsEighteen patients with 11 (61%) CNS WHO grade 1, 6 (33%) grade 2, and 1 (6%) grade 3 meningiomas were included. Median follow-up was 42 months (range 3–88). Five (28%) patients had a recurrence, but none were associated with the bone flap. Two (11%) wound infections requiring explant surgery occurred. Six (33%) patients required a further operation. Two operations were for recurrences, one was for infection, one was a washout and wound exploration but no evidence of infection was found, one patient requested the removal of a small titanium implant, and one patient required a ventriculoperitoneal shunt for a persistent CSF collection. There were no cases of bone flap resorption and cosmetic outcome was not routinely recorded.ConclusionEITC is feasible and fast to perform with good outcomes and cost-effectiveness compared to other reconstructive methods. We observed similar recurrence rates and lower infection rates requiring explant compared to the largest series of cranioplasty in meningioma. Cosmetic outcome is universally under-reported and should be reported in future studies.

Radiation levels outside a patient undergoing 177Lu-PSMA radioligand therapy

Understanding the spatial distribution of radiation levels outside of a patient undergoing 177Lu radioligand therapy is not only helpful for conducting correct tests for patient release, but also useful for estimation of its potential exposure to healthcare workers, caregivers, family members, and the general public. In this study, by mimicking the 177Lu-labeled prostate-specific membrane antigen radioligand therapy for prostate cancers in an adult male, the spatial distribution of radiation levels outside of the phantom was simulated based on the Monte Carlo software of Particle and Heavy Ion Transport System, and verified by a series of measurements. Moreover, the normalized dose rates were further formulized on the three transverse planes representing the heights of pelvis, abdomen and chest. The results showed that the distributions of radiation levels were quite complex. Multi-directional and multi-height measurements are needed to ensure the external dose rate to meet the release criteria. In general, the radiation level was higher at the horizontal plane where the source was located, and the levels in front and behind of the body were higher than those of the left and right sides at the same height. The ratio of simulated dose rates to measured ones ranged from 0.82 to 1.19 within 1 m away from the body surface in all directions. Based on the established functions, the relative root mean square deviation between the calculated and simulated values were 0.21, 0.25 and 0.23 within a radius of 1 m on the pelvis, abdomen and chest transverse planes, respectively. It is expected that the results of this study would be helpful for guiding the test of extracorporeal radiation to determine the patient’s release, and of benefit to estimate the radiation exposure to others.

Recycled bone grafts treated with extracorporeal irradiation or liquid nitrogen freezing after malignant tumor resection.

Recycled bone autografts prepared using extracorporeal irradiation (ECIR) or liquid nitrogen freezing (LNF) methods have been used for the reconstruction of skeletal elements after wide resection of sarcomas involving bone tissues. Few reports include long-term follow-up data for histological analyses of recycled autografts, particularly in the case of ECIR autografts. A total of 34 malignant bone and soft tissue tumors were resected and reconstructed using 11 ECIR- and 23 LNF-recycled autografts; the mean postoperative follow-ups were 14 and 8 years, respectively. ECIR was used for either osteosarcomas or Ewing sarcomas, whereas in addition to these tumors LNF was used for chondrosarcomas and soft tissue sarcomas involving bone tissues. Recycled bone was implanted as total bone, osteoarticular, or intercalary grafts, with or without prosthesis or vascularized fibular grafts. The 10-year graft survival rate was similar between groups, 81.8% using ECIR and 70.2% using LNF. There were no autograft-related tumor recurrences in either group. Graft survival was unrelated to type of graft or additional procedures. Complication rates tended to be higher using ECIR (64%) compared with LNF (52%) and the infection rate was significantly higher with ECIR (27%) versus LNF (0%). At the final assessment, plain radiographs revealed original recycled bone was present in 7 of 11 ECIR cases and in zero cases treated with LNF autografts, indicating that recycled bone treated with LNF autografts was remodeled into new bone. Histological examination of ECIR-treated bones revealed a delayed and incomplete endochondral ossification process, necrosis and empty lacunae. Conversely, LNF autografts showed remodeled bones with normal trabecular structures. ECIR and LNF treatment of autografts provided adequate tumor control with acceptable clinical results as a reconstruction method.

Our Experience With Extracorporeal Irradiation and Reimplantation of the Irradiated Bone for the Reconstruction of Bone Defects Following Tumor Resection.

With tremendous improvement in the survival of patients with malignant bone tumors, there is a greater emphasis on the functional outcome and durability of reconstruction following tumor resection. Tumor resection and extracorporeal irradiation (ECI) followed by reimplantation of the irradiated bone in malignant bone tumors is drawing popularity across various centers. In this study, we aim to put forward our experience with ECI, the outcomes achieved, and the complications faced by us. This is a prospective study conducted in patients with malignant and locally aggressive bone tumors who underwent ECI at our center. A total number of 20 patients were selected for the study and followed up for a mean duration of 32.5 months (maximum duration: 58 months, minimum duration: eight months). Orthopedic outcome was measured using the Enneking score. We assessed for local recurrence, functional outcome, union, and complications during the follow-up. During the course of follow up, local recurrence was seen in two patients. The mean MSTS score of the remaining patients was found to be 23.6. Complications seen included limb length discrepancy, surgical site infection, and graft lysis. Tumor resection and ECIis an effective procedure for biological reconstruction which gives satisfactory functional outcomes. In spite of certain complications, patients expressed satisfaction with the overall outcome of the procedure.

Comparison of the Results of Patients Treated With Limb-Sparing Treatment Options in Malignant Bone Tumors: Sharing the Experience of Twelve Bicentric Patients.

Extremity-sparing surgery should be the main objective if a functional extremity is to be obtained in cases of malignant bone tumors. After extensive resection, numerous techniques have been described to reconstruct bone defects. This study aimed to compare the outcomes of patients who underwent external radiation therapy and liquid nitrogen biological reconstruction at two different facilities. The study included 12 patients who received biological reconstruction therapy for bone sarcoma and had at least two years of follow-up. Demographic data, pathological diagnosis, presence of systemic metastasis, and recurrence during follow-up were among the information logged. Patients who used liquid nitrogen were placed in group 1, and those who underwent external irradiation were placed in group 2. After being contacted for their final follow-up appointments, the outcomes were compared by recording the Musculoskeletal Tumor Society Score (MSTSS). For participants with a mean age of 10.75±3.6 (5-17), the follow-up period was 30.2±16.3 months in total. In contrast to the patients in group 1, who experienced union on average after 7.5±1.2 months, those in group 2 experienced union after 7.6±1.1 months. Patients in group 1 had an MSTSS of 75.5±11.8%, while those in group 2 had a score of 77±4.4.There was no discernible difference between the two groups' union times (p>0.05). There was no statistically significant difference between the two groups' MSTSS (p>0.05). After tumor resection, extracorporeal radiation therapyand the application of liquid nitrogen are still useful treatment options and neither of them is superior to the other.

Dispersion-corrected extracorporeal arterial input functions in PET studies of mice: a comparison to intracorporeal microprobe measurements

BackgroundKinetic modelling of dynamic PET typically requires knowledge of the arterial radiotracer concentration (arterial input function, AIF). Its accurate determination is very difficult in mice. AIF measurements in an extracorporeal shunt can be performed; however, this introduces catheter dispersion. We propose a framework for extracorporeal dispersion correction and validated it by comparison to invasively determined intracorporeal AIFs using implanted microprobes.ResultsThe response of an extracorporeal radiation detector to radioactivity boxcar functions, characterised by a convolution-based dispersion model, gave best fits using double-gamma variate and single-gamma variate kernels compared to mono-exponential kernels for the investigated range of flow rates. Parametric deconvolution with the optimal kernels was performed on 9 mice that were injected with a bolus of 39 ± 25 MBq [18F]F-PSMA-1007 after application of an extracorporeal circulation for three different flow rates in order to correct for dispersion. Comparison with synchronous implantation of microprobes for invasive aortic AIF recordings showed favourable correspondence, with no significant difference in terms of area-under-curve after 300 s and 5000 s. One-tissue and two-tissue compartment model simulations were performed to investigate differences in kinetic parameters between intra- and extracorporeally measured AIFs. Results of the modelling study revealed kinetic parameters close to the chosen simulated values in all compartment models.ConclusionThe high correspondence of simultaneously intra- and extracorporeally determined AIFs and resulting model parameters establishes a feasible framework for extracorporeal dispersion correction. This should allow more precise and accurate kinetic modelling in small animal experiments.

PO-1548 Role of extra corporeal radiation in bone tumors

PO-1548 Role of extra corporeal radiation in bone tumors

Factors affecting the incorporation of extracorporeally irradiated autograft for the treatment of bone tumours-a retrospective analysis from a tertiary referral centre.

Re-implantation of the tumor bearing autograft following extracorporeal radiation therapy (ECRT) has been established as an oncologically safe biological reconstruction technique following resection of bone sarcomas. However, factors affecting the ECRT graft-host bone incorporation have not been fully investigated. An insight into the factors that influence graft incorporation can circumvent the complications and increase graft survival. A total of 96 osteotomies in 48 patients with intercalary resections of primary extremity bone sarcomas (mean age 15.8years, mean follow-up 42.1months) were analyzed retrospectively for factors ECRT autograft-host bone union. On univariate analysis, age < 20years, metaphyseal osteotomy site, V-shaped diaphyseal osteotomy, and use of additional plate at diaphyseal osteotomy had a significantly faster time to union, while gender, tumour type, bone involved, resection length, chemotherapy, type of fixation, and use of intra-medullary fibula did not influence union time. In multivariate analysis, V-shaped diaphyseal osteotomy and use of additional plate at diaphyseal ostetomy were the independent factors with favourable time to union. None of the analyzed factors was found to have a significant effect on the union rate. The major complications were non-union in 11.4% patients, graft failure in 2.1%, infection in 12.5%, and soft tissue local recurrences in 14.5% patients. Modified diaphyseal osteotomy and augmentation of the stability of the reconstruction using additional small plates enhance the incorporation of ECRT autograft.

Extracorporeal irradiation in malignant bone tumors: Single institution experience and review of literature.

In the last couple of decades, the management of malignant bone tumor (MBT) has seen a sea change. With the advent in surgical technics, radiation therapy, and chemotherapy, it has moved from disabling amputation to limb salvage surgery. Extracorporeal irradiation (ECI) and re-implantation of resected bone is a useful method of limb salvage of MBTs. In our study, we analyzed and presented the results of 8 cases of MBTs treated with this modality. Between 2014 and 2017, 8 patients with primary MBT were enrolled for ECI technique who are meeting the eligibility criteria. Before taking the patient for ECI treatment, a multispecialty tumor board discussion was done for each patient. All of them received neo-adjuvant and adjuvant chemotherapy except the patients with histology of giant cell tumor. Following neoadjuvant chemotherapy bone excision surgery was performed, and the resected bone was taken for ECI with the dose of 50 Gray in a single fraction. After ECI, bone segment was re-implanted at osteotomy site in the same setting. After completion of adjuvant chemotherapy, the patients were then followed up for any sequelae, local and systemic control, ambulation, and functional outcome. Out of 8 patients, there were 5 males and 3 females with mean age of 22 (range 13-36). The involved bone was the tibia in 6 patients, ischium in 1 patient, and femur in 1 patient. Histopathologically, the malignancies included 3 osteosarcoma, 3 Giant cell tumor, 1 Ewing's sarcoma and 1 chondrosarcoma. At median follow-up of 12 months (range 6-26 months), local control rate was 87.5% and systemic control rate was 75%. Perioperative ECI and re-implantation is a useful, convenient, and inexpensive technique. The overall treatment time is reduced. The patient's own bone fits perfectly to the resection site with reduced risk of graft site infection. The risk of local recurrence due to tumor re-implantation is negligible with tumoricidal radiation doses of ECI, and it is usually associated with manageable sequelae. Recurrence rates are acceptable and salvageable with surgery.

Personalized 3D-printed guide in malignant bone tumor resection and following reconstruction – 17 cases in pelvic and extremities

IntroductionCustomized accurate tumor resection and individualized reconstruction is a challenging in treatment of malignant bone tumor. Three-dimensional (3D)-printing technique is now widely used in the resection and following reconstruction of malignant bone tumor, which included but not limited to tumor model, osteotomy guide and customized implant. MethodsWe retrospectively reviewed 17 patients, who underwent limb salvage surgery by using 3D-printed guide at a single center between August 2014 and October 2019. The median duration of follow-up was 26.5 months. Osteosarcoma (41.2%) were the predominant diagnoses. The functional outcomes were assessed by Musculoskeletal Tumor Society (MSTS) functional score. We also analyzed survival status, intraoperative data (blood loss, operation time and resection length), reconstruction method, margin outcomes and complications. ResultsWe totally performed 93 guided osteotomies on affected bone and allograft bone in 17 patients. Reconstruction in 12 cases was performed with biological technique: allograft combined with autograft was used in 7 cases. 11 of 12 (91.7%) cases showed a good bone healing in both allograft and autograft. 1 of 12 (8.3%) cases had allograft necrosis. Additional intra-operative extracorporeal radiation was performed in 3 pelvic cases for reconstruction. 63 of 64 (98%) osteotomies achieved wide resection and negative margin. All the cases had successful limb salvage result without amputation. At the latest follow up, the mean MSTS Score was 24 (range: 13–30), 12 patients alive with no evidence of disease, 1 patient alive with disease, 5 patients had died of disease and 5 years overall survival is 73.3%. The most common complications are wound healing disorder in 4 cases (23.5%) and infection in 3 cases (17.6%). ConclusionThe 3D-printed resection guide was easy to use and showed promise in the field of orthopedic oncology. It can not only used in primary malignant bone tumor personalized resection but also in shaping structural bone allograft in biological reconstruction, which can achieve a safety surgical margin and individualized resection at the same time.

A rare case of bilateral retinoblastoma metastasizing into the forearm

We present a case of an 8-year-old boy who had undergone chemotherapy with transpupillary thermotherapy for bilateral retinoblastoma (RB) at the age of 6 months. The patient had left forearm pain at the present visit. Bilateral ocular examination did not reveal any signs of RB reactivation. However, bone scan with technetium 99m-methyl diphosphonate (99mTc–MDP) and magnetic resonance imaging (MRI) showed the presence of metastasis in the proximal end of the ulnar bone, which was confirmed on bone marrow biopsy. Based on PCR study and molecular analysis, Ewing's sarcoma was ruled out and the patient was confirmed to have metastatic RB. Subsequently, he underwent chemotherapy along with wide excision of left proximal ulna + extracorporeal radiation therapy (ECRT) + plate reconstruction. At 15-month follow-up, the patient was stable with absence of recurrence of RB. This case highlights the need for long-term follow-up of patients with RB and the need for timely detection and management of metastasis.

Radiotherapy inhibits neointimal hyperplasia after artificial vascular replacement through Skp2/P27kip1.

We aimed to establish an animal model of abdominal aortic vascular replacement in mongrel dogs to investigate the effect of extracorporeal radiotherapy on the intima. Twenty healthy mongrel dogs were randomly divided into four groups: 5-week control group, 5-week radiotherapy group, 10-week control group and 10-week radiotherapy group. We first performed an artificial vascular replacement of the abdominal aortic segment. The radiotherapy group received external radiotherapy with a dose of 7 Gy for 4 days. The thickness of neointimal hyperplasia, immunoreactivity and expression of proliferation-related factors were detected by hematoxylin and eosin (HE) staining, immunohistochemistry, quantitative real-time polymerase chain reaction (qRT-PCR )and western blotting at 5 and 10 weeks after the reconstruction. The results showed that the intimal thickness of the artificial blood vessel in the 5- and 10-week radiotherapy groups was thinner than that in the control groups by HE staining. The immunoreactivity and expression levels of Skp2, c-Myc and CyclinE1 were significantly decreased in the radiotherapy groups than those in control groups by immunohistochemistry, qRT-PCR and western blotting. On the contrary, immunoreactivity and expression levels of P27kip1 were increased. In conclusion, we discovered that postoperative external radiotherapy significantly decreases the intimal hyperplasia of artificial blood vessels by regulating c-Myc-Skp2-P27-CyclinE1 network.

Influence of ultraviolet radiation on kinetic characteristics in erythrocytes

Erythrocytes were irradiated with an ultraviolet lamp of the VMT type (λ = 253.7 nm). The kinetic characteristics in irradiated and non-irradiated blood samples were compared by the acid (chemical) erythrogram method and by the counter transport method. Obtained:&#x0D; - by the method of acidic erythrograms it was found that in ultraviolet-irradiated blood samples there is a decrease in the time of half hemolysis.&#x0D; - ultraviolet radiation increases the speed of counter movement of ions through erythrocyte membranes.&#x0D; - a decrease in the time of half hemolysis and an increase in the rate of counter transfer of ions, irradiated blood samples, is due to a decrease in the "effective" thickness of the near-membrane diffusion layer - an immiscible layer of water adjacent to the erythrocyte membrane.&#x0D; A decrease in the "effective thickness" of the near-membrane water layer changes the rate of metabolic processes in the "cell - intercellular medium" system, changing the mode of cell functioning. The altered mode of functioning is a biological response to light radiation. Red blood cells with an altered mode of functioning are stimulus signals that force the body to mobilize resources to fight pathology. These circumstances can predict the creation of a universal phototherapeutic equipment for extracorporeal blood irradiation based on LEDs with certain exposure parameters. Figs.: 4. Tabl.: 3. Refs.: 12 titles.

Recurrent Hurthle cell thyroid carcinoma does not preclude long-term survival: a case report and review of the literature

BackgroundFollicular thyroid carcinoma is the second most common malignancy of the thyroid gland. In 2016, the so-called Hurthle cell thyroid carcinoma, formerly known as the oxyphilic variant of the follicular thyroid carcinoma, was reclassified by the World Health Organization as a separate pathological entity, which accounts for approximately 3% of all thyroid cancers. Although Hurthle cell thyroid carcinomas are known for their more aggressive tumor biology, metastases are observed in a minority of cases, and long-term survival can be expected. However, disseminated disease is often associated with poor outcome.Case presentationIn the presented case, a 63-year-old Caucasian female was incidentally diagnosed with Hurthle cell thyroid carcinoma after undergoing hemithyroidectomy for a nodular goiter. Following completion thyroidectomy, two courses of radioactive iodine therapy were administered. After 4 years of uneventful follow-up, the patient gradually developed metastases in five different organs, with the majority representing unusual sites, such as heart, kidney, and pancreas over a course of 14 years. The lesions were either treated with radioactive iodine therapy or removed surgically, depending on iodine avidity.ConclusionFollicular and Hurthle cell thyroid carcinoma are known to potentially spread hematogenously to typical sites, such as lung or bones, however; unusual metastatic sites as presented in our case can also be observed. A search of the literature revealed only scattered reports on patients with multiple metastases in unusual locations. Furthermore, the observed long-term survival of our patient is contradictory to the existing data. As demonstrated, recurrent disease may appear years after the initial diagnosis, emphasizing the importance of consistent aftercare. Radioactive iodine therapy, extracorporeal radiation therapy, and surgical metastasectomy are central therapeutic components. In summary, our case exemplifies that thorough aftercare and aggressive treatment enables long-term survival even in recurrent Hurthle cell thyroid carcinoma displaying unusual multisite metastases.

Comparison of recycled autograft versus allograft in osteosarcoma with pathological fracture.

The recycled autograft in biological reconstruction for osteosarcoma has satisfactory outcome. There are few studies about its efficacy in pathological fracture. The aim of the study is to compare the clinical results of recycled autograft to those of allograft in patients with high-grade osteosarcoma with pathological fracture. Between October 2010 and March 2018, 30 patients with osteosarcoma combining pathological fracture underwent biological reconstruction. Eleven patients received recycled autograft via extracorporeal irradiation or freezing nitrogen and nineteen patients restored bone defect via allograft to accomplish biological reconstruction. The mean follow-up was 58.1months (range 12-120). The mean time to graft-host union of limbs reconstructed using recycled autografts and allografts was 17.45 ± 13.54 and 12.63 ± 12.62months, respectively, with no significant difference observed between groups (p = 0.176). The fiveyear probability of graft failure therefore did not significantly differ between groups (p = 0.245). The patient fiveyear survival rate was similar (p = 0.229). Post-operative complication rates were similar for the recycled autograft group (54.5%) and the allograft group (57.9%). The recycled autograft showed comparable clinical results, graft-host union time, complication rate, and graft survival to allograft in biological reconstruction for osteosarcoma with pathological fracture.

Comparative efficacy of intraoperative extracorporeal irradiated and alcohol-inactivated autograft reimplantation for the management of osteosarcomas\u2014a multicentre retrospective study

BackgroundBiologic bone reconstruction in limb salvage surgery for the treatment of malignant bone tumours has always been controversial. The various inactivation methods, their convenience and stability, the curative effects elicited and associated costs all need to be considered. This study aimed to compare the clinical efficacy of intraoperative extracorporeal irradiated reimplantation with alcohol-inactivated autograft reimplantation for limb salvage surgery in patients with osteosarcoma.MethodsWe retrospectively analysed 28 patients with osteosarcoma, 14 patients treated with intraoperative cobalt 60 irradiation and reimplantation (group A), and 14 patients treated by alcohol-inactivated autograft reimplantation (group B). The postoperative complications and clinical efficacy of each treatment method were compared by statistical analysis.ResultsThe local recurrence rate was 14.3% in each group. Complete bony union was achieved in 64.3% of patients in group A and 71.4% of patients in group B. The overall 5-year survival rate was 71.4% in group A and 78.6% in group B. The mean Musculoskeletal Tumor Society (MSTS) score was 25.33 ± 4.72 (range 15–30) in group A and 24.00 ± 5.85 (range 15–30) in group B, and the mean International Society of Limb Salvage (ISOLS) score was 25.79 ± 5.13 (range 20–36) in group A and 26.14 ± 5.33 (range 20–30) in group B. P < 0.05 was considered to indicate a significant difference. The results showed that the long-term clinical efficacy did not differ significantly between the two methods.ConclusionsIn limb salvage surgery for osteosarcoma, intraoperative extracorporeal irradiation and alcohol-inactivated autograft reimplantation yielded equivalent outcomes. The alcohol-inactivated method may be a much more convenient and inexpensive way to reconstruct bone defects. Additional studies as well as more case studies are needed to fully evaluate the clinical efficacy and safety of this treatment method.

Pelvic Chondrosarcoma Treated by En Bloc Resection with Patient-Specific Osteotomy Guides and Reimplantation of the Extracorporeally Irradiated Bone as an Osseocartilaginous Structural Orthotopic Autograft: A Report of Two Cases with Description of the Surgical Technique

Primary tumors of the pelvis are considered difficult to treat due to the complex anatomy and the proximity of important neurovascular structures. The surgical armamentarium for the treatment of these tumors has evolved with the help of cutting-edge technology from debilitating hemipelvectomies to solutions such as precise resections guided by patient-specific instruments or computer navigation and reconstruction by modular prostheses, 3D-printed custom-made implants, or orthotopic autograft reimplantation after extracorporeal irradiation. Different combinations of these techniques have been described in the literature with various rates of success. We present two cases of pelvic chondrosarcomas successfully treated by a combination of periacetabular resection with patient-specific osteotomy guides and orthotopic reimplantation of the extracorporeally irradiated autograft resulting in retention of the native hip.

Reconstructive Challenges of Distal Tibia Bone Tumors: Extracorporeally Irradiated Autograft Combined with a Nonvascularized Autograft Fibula for Superior Reconstruction and Functional Outcomes When Compared to Ipsilateral Pedicled Fibula Transfer Alone.

Introduction Traditionally, centralization of the fibula with fusion across the tibiotalar joint has been used to reconstruct distal tibial defects. Although effective, it requires long periods of protected weight-bearing. The fibula or the fixation often fails before fibular hypertrophy necessitating multiple additional surgeries. A method of using ECRT with the available ipsilateral fibula (nonvascularized) to reconstruct the distal tibia defect with the aim of early return to weight-bearing was evolved. This paper documents our early experience. Patients and Methods. Four patients; with the diagnosis of osteosarcoma in 3 patients and recurrent giant cell tumor of the bone in 1 patient, underwent resection of the distal tibia for tumors between 2017 and 2019. Extracorporeally irradiated (50 Gy) distal tibia along with ipsilateral nonvascularized fibula was used to bridge the defect and fuse the tibiotalar joint. A plate was used to rigidly hold the construct. The final outcome was compared to the historical control group that underwent only pedicled ipsilateral fibula transposition and ankle arthrodesis without recycled autograft or allograft between 2009 and 2017. Oncological reconstruction and functional outcomes were compared for each group. Patient reported outcomes on the acceptability of ankle fusion; cosmesis and function were analyzed and compared between the two groups. Results The mean resection length in the study group (4 patients) was 7.75 cm (7 to 8.5 cm). As compared to the historical cohort of 7 patients, the study population showed statistically superior results in all reconstruction, functional, and patient-reported outcomes except time to proximal junction union (p=0.068). There were no reconstruction failures, infection, or nonunions in the study group, whereas the control comparative group had 2 proximal junction nonunions and a mean time to fibular hypertrophy of 143 weeks (82 to 430 weeks) with fibula centralization. Earlier weight-bearing was allowed (mean 26.75 weeks; median 27 weeks) compared to (mean 80.75 weeks; median 80 weeks) in the control group. Conclusion We think that ECRT with ipsilateral vascularized fibula is a promising method of reconstructing the distal tibia. The recycled autograft tibia added strength to the distal tibia construct in our study and aided the anatomical reconstruction of the distal tibia. The patient-reported outcomes for cosmesis and acceptability add to the benefits of performing this procedure. Consistent early union across the proximal junction and earlier weight-bearing were clear advantages of this method.

Intra-operative extracorporeal radiation therapy for skeletally immature patients with malignant bone tumours

ABSTRACT BACKGROUND: Management of malignant bone tumours has changed dramatically in recent years. Neoadjuvant chemotherapy, irradiation and conservative surgery have improved local control as well as functional outcome. Depending on the histology of the lesion, other modalities like chemotherapeutic agents or radiation can be selected in place of surgical intervention. Operative intervention is the main modality with wide marginal excision and fixation of bone graft from different sources or mega prosthesis to maintain congruity of the bone anatomy. Reconstruction, optimum fit and stability at the affected site are the major areas of concern with this modality. Radiation given outside the body to kill the tumour cells in the bone is called extracorporeal radiotherapy (ECRT). After resection of the bone, it is cleaned of all the surrounding soft tissue and marrow contents and placed in a container. It is then subjected to 50 Gy of radiation which kills all the tumour cells. METHODS: The study was conducted from June 2014 to May 2020, and included 15 patients (out of 18) diagnosed with either Ewing's sarcoma or osteosarcoma. They were followed up for an average of 4.44 years, up to May 2020. All 15 cases were analysed for bony union at the osteotomy sites. Cases reported with poorly differentiated sarcomas (total three) were subjected to immunohistochemistry and managed with other modalities of treatment. RESULTS: The average time for union of irradiated bone was 8.1 months (range 5-10; the metaphyseal end united faster than the diaphyseal end). At the final follow-up, the functional status was determined using the Musculoskeletal Tumour Society (MSTS) scoring system. Ninety-three per cent of patients had involvement of the lower limb (14 out of 15). All patients (except one who developed recurrence) did not have symptoms of the disease and no one had died at last follow-up. CONCLUSION: Biological limb salvage procedures are considered a successful treatment and a welcome alternative for patients who either cannot afford or be treated with an endoprosthesis. Early diagnosis and referral to specialised unit is of vital importance. This procedure can be used for selected patients with malignant bone tumours. Cost factors, and social and cultural considerations also play a role Level of evidence: Level 4. Keywords: ECRT, extracorporeal radiation therapy, malignant bone tumours, bone sarcoma, osteosarcoma, Ewing's sarcoma