The development and validation of a decision aid to facilitate patient choice of surgery versus radiotherapy for high-risk basal cell carcinoma.

Basal cell carcinoma (BCC) is an increasingly common cancer. For high-risk BCCs, there are several treatment options, with similar efficacies. The current best practice in deciding upon a particular treatment is for a patient-centred approach. At present, there are few resources available for patients to assist their choice. This reduces patient autonomy and increases the burden on clinicians within clinic. Patient decision aids (PDAs) have been shown to increase patient autonomy and facilitate shared decision-making. Currently, there is no published PDA designed to facilitate the decision between surgical management or radiotherapy in high-risk BCCs. We developed a novel decision aid designed along the International Patient Decision Aid Standards to fill this clinical need, and evaluated its acceptance by both patients and clinicians. We describe the challenges faced at initial alpha and subsequent beta testing, and go on to validate our PDA with both the Decisional Conflict Scale and the nine-item Shared Decision Making Questionnaire (SDMQ9). We include an example of the PDA and encourage other units to modify the PDA for their own use.

A phase II study on the neo-adjuvant combination of pazopanib and radiotherapy in patients with high-risk, localized soft tissue sarcoma.

PURPOSE: A prior phase I study showed that the neo-adjuvant combination of pazopanib and radiotherapy was well tolerated, and induced promising pathological responses in soft-tissue sarcoma patients. Results of the subsequent prospective, multicenter phase II, PASART-2 trial are presented here, further investigating the efficacy and safety of this combination. PATIENTS AND METHODS: Patients with high-risk, localized soft-tissue sarcoma received neo-adjuvant radiotherapy, 50 Gy in 25 fractions (PASART-2A) or with a subsequent dose de-escalation to 36 Gy in 18 fractions (PASART-2B). This was combined with 800 mg once daily pazopanib, which started one week before radiotherapy and finished simultaneously. After an interval of 4-8 weeks, surgical resection was performed. The primary endpoint was the rate of pathological complete responses (pCR), defined as ≤5% viable cells. RESULTS: 25 patients were registered in the study, 21 in PASART-2A and 4 in PASART-2B. After central pathology review, the combination treatment led to a pCR in 5 patients (20%). 17 patients (68%) experienced grade 3+ toxicities during neo-adjuvant treatment, of which the most common were alanine aminotransferase (ALT) elevation, aspartate aminotransferase (AST) elevation, and hypertension, all asymptomatic. Grade 3+ acute post-operative toxicities occurred in 5 patients (20%), of which the most common was wound infection. All patients completed the full radiotherapy regimen and underwent surgery. Pazopanib was discontinued before completion in 9 patients (36%), due to elevated ALT and/or AST, and shortly interrupted in 2 patients (8%), due to hypertension. CONCLUSION: Apart from asymptomatic hepatotoxicity, the study regimen was well tolerated. Although the pre-specified efficacy endpoint (30% pCR) was not met, a more than doubling of historical pCR rates after neo-adjuvant radiotherapy alone was observed, which warrants further investigation.

Outcome of Primary Desmoid Tumors at All Anatomic Locations Initially Managed with Active Surveillance.

BACKGROUND: The behavior of desmoid tumors is unpredictable and varies from spontaneous remission to symptomatic and radiologic progression. This study aimed to evaluate the radiologic and symptomatic course of the disease in patients initially managed with active surveillance. METHODS: Patients with a primary desmoid tumor at any anatomic location diagnosed between 1998 and 2016 were identified in a prospectively maintained database from a single sarcoma reference center in the United Kingdom. Inverse univariate Cox proportional hazard regression analyses were conducted to evaluate the course of the disease and indications for initiating treatment. RESULTS: The study identified 168 patients with a primary desmoid tumor initially managed with active surveillance. The tumors were located in the abdominal wall (n = 61, 36%), an extremity (n = 51, 30%), chest wall (n = 30, 18%), intra-abdominal site (n = 15, 9%), or elsewhere (n = 11, 6%). Of all the patients, 36% experienced radiologic progressive disease, 36% had stable disease, and 27% regressed. The patients younger than 50 years were more likely to progress (p = 0.046), whereas the patients with chest wall or upper-extremity tumors reported significantly more pain (p = 0.01). Eventually, 46% of the patients proceeded to treatment. The median time to start of treatment after initial surveillance was 31 months, whereas the median follow-up time for the patients not receiving any treatment was 40.5 months. The indications for initiation of treatment were pain (32%), progression (31%), or both (13%). CONCLUSIONS: Patients with desmoid tumors can be managed with initial active surveillance, although almost half of patients may eventually need treatment. Pain, tumor progression, or both are the most common indications for the initiation of treatment.

Desmoid fibromatosis through the patients' eyes: time to change the focus and organisation of care?

PURPOSE: Desmoid fibromatosis (DF) is a rare, unpredictable disease with no established, evidence-based treatments. Individual management is based on consensus algorithms. This study aimed to examine the specific health-related quality of life challenges faced by DF patients, current experiences and expectations of care. METHODS: Twenty-seven DF patients were purposively sampled from The Royal Marsden Hospital. Two focus groups and 13 interviews (males 12, females 15; mean age at study 39.5 years) explored health-related quality of life issues and experiences of healthcare. Thematic content was analysed. RESULTS: Discussions revealed four key themes (diagnostic pathway; treatment pathway; living with DF; supportive care). Diagnostic delay resulted from lack of recognition by patients and healthcare professionals. Some patients received an initial diagnosis of cancer, causing significant distress. Treatment decisions were challenging, and patients experienced uncertainty among clinicians about optimal therapies. Side-effects of treatment were severe, including fatigue, nausea, anorexia, low libido and depression. Pain was the most debilitating symptom and dependency on painkillers was a significant concern. Functional limitation and restricted mobility frequently affected daily activities. Patients experienced difficulty accomplishing their role in society; relationship problems, caring for children, employment and financial difficulties. Social isolation and lack of understanding were common. The psychological impact of this "life-changing and life-long" condition was profound. All patients requested knowledgeable healthcare professionals, more information, continuity of care and peer support. CONCLUSIONS: DF patients face complex physical, psychological and practical challenges. Comprehensive care services are needed. Increasing awareness may help to improve diagnostic pathways and overall patient experience.

Inhibitory Receptors Induced by VSV Viroimmunotherapy Are Not Necessarily Targets for Improving Treatment Efficacy.

Systemic viroimmunotherapy activates endogenous innate and adaptive immune responses against both viral and tumor antigens. We have shown that therapy with vesicular stomatitis virus (VSV) engineered to express a tumor-associated antigen activates antigen-specific adoptively transferred T cells (adoptive cell therapy, ACT) in vivo to generate effective therapy. The overall goal of this study was to phenotypically characterize the immune response to VSV+ACT therapy and use the information gained to rationally improve combination therapy. We observed rapid expansion of blood CD8+ effector cells acutely following VSV therapy with markedly high expression of the immune checkpoint molecules PD-1 and TIM-3. Using these data, we tested a treatment schedule incorporating mAb immune checkpoint inhibitors with VSV+ACT treatment. Unlike clinical scenarios, we delivered therapy at early time points following tumor establishment and treatment. Our goal was to potentiate the immune response generated by VSV therapy to achieve durable control of metastatic disease. Despite the high frequency of endogenous PD-1+ TIM-3+ CD8+ T cells following virus administration, antibody blockade did not improve survival. These findings provide highly significant information about response kinetics to viroimmunotherapy and juxtapose the clinical use of checkpoint inhibitors against chronically dysfunctional T cells and the acute T cell response to oncolytic viruses.

Treatment of retroperitoneal sarcoma: current standards and new developments.

PURPOSE OF REVIEW: Retroperitoneal sarcomas are rare tumors and with complex treatment. In this manuscript we give an overview of current standards in treatment of this disease and discuss new developments. RECENT FINDINGS: Surgery with complete resection of the primary tumor is still the only curative modality. The role of preoperative radiotherapy is not clear and is currently being investigated in a clinical trial. Neo-adjuvant chemotherapy is not the standard of care but can be considered occasionally when complete resection is uncertain. Local and distant recurrent disease carries a dismal prognosis, although long-term survival can be achieved. Liposarcomas tend to recur locally, whereas distant recurrences are more often seen in leiomyosarcoma and other subtypes. Outcome improves when patients are treated in high volume sarcoma centers. In the metastatic setting, newer systemic agents have recently been approved. SUMMARY: Treatment of retroperitoneal sarcomas is complex and all patients should be treated in multidisciplinary sarcoma centers. Increasing international collaboration of expert centers in sharing expertise and performing clinical trials might lead to better treatment and improved survival.

Pazopanib, a promising option for the treatment of aggressive fibromatosis.

Desmoid tumour/aggressive fibromatosis (DT/AF) is a rare soft-tissue neoplasm that is locally aggressive but does not metastasize. There is no standard systemic treatment for symptomatic patients, although a number of agents are used. Tyrosine kinase inhibitors have recently been reported to show useful activity. We reviewed our bi-institutional (Royal Marsden Hospital, Cambridge University Hospitals) experience with the tyrosine kinase inhibitor pazopanib in the treatment of progressing DT/AF. Eight patients with DT/AF were treated with pazopanib at Royal Marsden Hospital and Cambridge University Hospitals between June 2012 and June 2016. The median age of the patients was 37.5 (range: 27-60) years. The median duration of pazopanib treatment was 12 (range: 5-22) months and for three patients the treatment is ongoing. Three patients discontinued treatment early (patient preference, intolerable toxicity and logistical reasons, respectively). None of the patients showed radiological progression while on treatment, best responses according to Response Evaluation Criteria In Solid Tumors 1.1 were partial response in 3/8 and stable disease in 5/8 cases. Six patients derived clinical benefit from treatment in terms of improved function and/or pain reduction. Median progression-free survival was 13.5 (5-36) months. Only one patient experienced intolerable toxicity (grade 3 hypertension) leading to early treatment discontinuation. In our series of patients with DT/AF, pazopanib demonstrated important activity both in terms of symptom control (75%) and absence of radiological progression (100%). Results of ongoing confirmatory trials are eagerly awaited.

Combination Therapy With Reovirus and Anti-PD-1 Blockade Controls Tumor Growth Through Innate and Adaptive Immune Responses.

Oncolytic reovirus can be delivered both systemically and intratumorally, in both preclinical models and in early phase clinical trials. Reovirus has direct oncolytic activity against a variety of tumor types and antitumor activity is directly associated with immune activation by virus replication in tumors. Immune mechanisms of therapy include both innate immune activation against virally infected tumor cells, and the generation of adaptive antitumor immune responses as a result of in vivo priming against tumor-associated antigens. We tested the combination of local oncolytic reovirus therapy with systemic immune checkpoint inhibition. We show that treatment of subcutaneous B16 melanomas with a combination of intravenous (i.v.) anti-PD-1 antibody and intratumoral (i.t.) reovirus significantly enhanced survival of mice compared to i.t. reovirus (P < 0.01) or anti-PD-1 therapy alone. In vitro immune analysis demonstrated that checkpoint inhibition improved the ability of NK cells to kill reovirus-infected tumor cells, reduced T(reg) activity, and increased the adaptive CD8(+) T-cell-dependent antitumor T-cell response. PD-1 blockade also enhanced the antiviral immune response but through effector mechanisms which overlapped with but also differed from those affecting the antitumor response. Therefore, combination with checkpoint inhibition represents a readily translatable next step in the clinical development of reovirus viroimmunotherapy.

Dedifferentiated Liposarcoma: Updates on Morphology, Genetics, and Therapeutic Strategies.

Well-differentiated liposarcoma (WDL) and dedifferentiated liposarcoma (DDL) form the largest subgroup of liposarcomas, and represent a morphologic and behavioral spectrum of 1 disease entity, which arises typically in middle to late adult life, most frequently within the retroperitoneum or extremities. DDL is defined as nonlipogenic sarcoma that is juxtaposed to WDL, occurs as a recurrence of WDL or which can arise de novo, and typically has the appearance of undifferentiated pleomorphic or spindle cell sarcoma. DDL have a propensity for local recurrence, whereas distant metastasis is rarer, and behavior is related to anatomic site, with retroperitoneal neoplasms showing a significantly worse prognosis. Surgical resection remains the mainstay of treatment, and medical options for patients with aggressive recurrent or metastatic disease are limited. DDL share similar genetic abnormalities to WDL, with high-level amplifications of chromosome 12q14-15, including the MDM2 and CDK4 cell cycle oncogenes, and DDL harbor additional genetic changes, particularly coamplifications of 6q23 and 1p32. Novel therapies targeted at the gene products of chromosome 12 are being tested in clinical trials. We review the pathology and genetics of DDL, discussing morphologic patterns, immunohistochemical and genetic findings, the differential diagnosis, and future therapeutic strategies.

Mutated BRAF Emerges as a Major Effector of Recurrence in a Murine Melanoma Model After Treatment With Immunomodulatory Agents.

We used a VSV-cDNA library to treat recurrent melanoma, identifying immunogenic antigens, allowing us to target recurrences with immunotherapy or chemotherapy. Primary B16 melanoma tumors were induced to regress by frontline therapy. Mice with recurrent tumors were treated with VSV-cDNA immunotherapy. A Th17 recall response was used to screen the VSV-cDNA library for individual viruses encoding rejection antigens, subsequently targeted using immunotherapy or chemotherapy. Recurrent tumors were effectively treated with a VSV-cDNA library using cDNA from recurrent B16 tumors. Recurrence-associated rejection antigens identified included Topoisomerase-IIα, YB-1, cdc7 kinase, and BRAF. Fourteen out of 16 recurrent tumors carried BRAF mutations (595-605 region) following frontline therapy, even though the parental B16 tumors were BRAF wild type. The emergence of mutated BRAF-containing recurrences served as an excellent target for BRAF-specific immune-(VSV-BRAF), or chemo-(PLX-4720) therapies. Successful PLX-4720 therapy of recurrent tumors was associated with the development of a broad spectrum of T-cell responses. VSV-cDNA technology can be used to identify recurrence specific antigens. Emergence of mutated BRAF may be a major effector of melanoma recurrence which could serve as a target for chemo or immune therapy. This study suggests a rationale for offering patients with initially wild-type BRAF melanomas an additional biopsy to screen for mutant BRAF upon recurrence.

Cytokine conditioning enhances systemic delivery and therapy of an oncolytic virus.

Optimum clinical protocols require systemic delivery of oncolytic viruses in the presence of an intact immune system. We show that preconditioning with immune modulators, or loading virus onto carrier cells ex vivo, enhances virus-mediated antitumor activity. Our early trials of systemic reovirus delivery showed that after infusion reovirus could be recovered from blood cells--but not from plasma--suggesting that rapid association with blood cells may protect virus from neutralizing antibody. We therefore postulated that stimulation of potential carrier cells directly in vivo before intravenous viral delivery would enhance delivery of cell-associated virus to tumor. We show that mobilization of the CD11b(+) cell compartment by granulocyte macrophage-colony stimulating factor immediately before intravenous reovirus, eliminated detectable tumor in mice with small B16 melanomas, and achieved highly significant therapy in mice bearing well-established tumors. Unexpectedly, cytokine conditioning therapy was most effective in the presence of preexisting neutralizing antibody. Consistent with this, reovirus bound by neutralizing antibody effectively accessed monocytes/macrophages and was handed off to tumor cells. Thus, preconditioning with cytokine stimulated recipient cells in vivo for enhanced viral delivery to tumors. Moreover, preexisting neutralizing antibody to an oncolytic virus may, therefore, even be exploited for systemic delivery to tumors in the clinic.

The profile of tumor antigens which can be targeted by immunotherapy depends upon the tumor's anatomical site.

Previously, we showed that vesicular stomatitis virus (VSV) engineered to express a cDNA library from human melanoma cells (ASMEL, Altered Self Melanoma Epitope Library) was an effective systemic therapy to treat subcutaneous (s.c.) murine B16 melanomas. Here, we show that intravenous treatment with the same ASMEL VSV-cDNA library was an effective treatment for established intra-cranial (i.c.) melanoma brain tumors. The optimal combination of antigens identified from the ASMEL which treated s.c. B16 tumors (VSV-N-RAS+VSV-CYTC-C+VSV-TYRP-1) was ineffective against i.c. B16 brain tumors. In contrast, combination of VSV-expressed antigens-VSV-HIF-2α+VSV-SOX-10+VSV-C-MYC+VSV-TYRP1-from ASMEL which was highly effective against i.c. B16 brain tumors, had no efficacy against the same tumors growing subcutaneously. Correspondingly, i.c. B16 tumors expressed a HIF-2α(Hi), SOX-10(Hi), c-myc(Hi), TYRP1, N-RAS(lo)Cytc(lo) antigen profile, which differed significantly from the HIF-2α(lo), SOX-10(lo), c-myc(lo), TYRP1, N-RAS(Hi)Cytc(Hi) phenotype of s.c. B16 tumors, and was imposed upon the tumor cells by CD11b(+) cells within the local brain tumor microenvironment. Combining T-cell costimulation with systemic VSV-cDNA treatment, long-term cures of mice with established i.c. tumors were achieved in about 75% of mice. Our data show that the anatomical location of a tumor profoundly affects the profile of antigens that it expresses.

Predicting radiotherapy response, Toxicities and quality-of-life related functional outcomes in soft tissue sarcoma of the extremities (PredicT) using dose-volume constraints development: a study protocol.

INTRODUCTION: Radiotherapy improves local tumour control in patients with soft tissue sarcoma of the extremities (STSE) but it also increases the probability of long-term toxicities such as tissue fibrosis, joint stiffness and lymphoedema. The use of radiation dose and volume thresholds, called dose constraints, may potentially reduce the development of toxicities in STSE. The aim of this study is to determine predictors of radiotherapy-related side effects for STSE. METHODS AND ANALYSIS: Predicting radiotherapy response, Toxicities and quality-of-life related functional outcomes in soft tissue sarcoma of the extremities (PredicT) is a multicentre observational study comprising two cohorts (PredicT A and B). PredicT A, a retrospective analysis of the UK VorteX (NCT00423618) and IMRiS clinical trials (NCT02520128), is aimed at deriving a statistical model for development of dose-volume constraints. This model will use receiving operator characteristics and multivariate analysis to predict radiotherapy side effects and patient-reported outcomes. PredicT B, a prospective cohort study of 150 patients with STSE, is aimed at testing the validity of those dose-volume constraints. PredicT B is open and planned to complete recruitment by September 2024. ETHICS AND DISSEMINATION: PredicT B has received ethical approval from North West - Liverpool Central Research Ethics Committee (20/NW/0267). Participants gave informed consent to participate in the study before taking part. We will disseminate our findings via publications, presentations, national and international conference meetings and engage with local charities. TRIAL REGISTRATION NUMBER: NCT05978024.

Biphenotypic Sinonasal Sarcoma: Case Reports of Diagnostic Findings and Clinical Management of 3 Cases.

BACKGROUND: Biphenotypic sinonasal sarcoma (BSNS) is a rare spindle cell sarcoma distinctly arising in the sinonasal area, with dual myogenic and neural differentiation, and characterised by the presence of PAX3 gene fusion, typically with MAML3. Although the majority may be indolent, up to 25% of cases reported in the literature are locally aggressive, with invasion of adjacent critical structures in the head and neck region. CASE REPORT: We report 3 cases of BSNS reviewed at our institution between 2016-2020 in addition to the current literature. Patient 1 underwent surgery followed by adjuvant radiotherapy but relapsed 24 months later and was not fit for systemic anticancer therapy and managed with palliative care. Due to comorbidities, patient 2 was recommended for active surveillance, with a view to intervening with radiotherapy should there be evidence of clinical progression. At 60 months, the nasal cavity mass remained stable on serial imaging. Patient 3 underwent primary surgical R0 resection and was offered adjuvant post operative radiotherapy 60 Gy/30 fractions/6 weeks but opted for active surveillance and has no clinical or radiological evidence of recurrence 22 months after surgery. CONCLUSION: The primary management for BSNS is surgical resection. We recommend discussing the role of postoperative adjuvant radiotherapy 60 Gy/30 fractions/6 weeks in patients who are fit for treatment. In clinical practice, dose levels will be constrained by surrounding normal tissues. At present, the role of systemic anticancer therapy is undefined. A prospective registry of ultra-rare cases may provide an evidence base with which to select optimal treatment strategies for BSNS in the future.

Case report: L5 tomita En bloc spondylectomy for oligometastatic liposarcoma with post adjuvant stereotactic ablative radiotherapy.

Introduction: Tomita En-bloc spondylectomy of L5 is one of the most challenging techniques in radical oncological spine surgery. A 42-year-old female was referred with lower back pain and L5 radiculopathy with a background of right shoulder liposarcoma excision. CT-PET confirmed a solitary L5 oligometastasis. MRI showed thecal sac indentation hence wasn't suitable for Stereotactic Ablative Radiotherapy (SABR) alone. The seeding nature of sarcoma prevents the indication of separation surgery hence excisional surgery is considered for radical curative treatment. This case report demonstrates dual-staged modified TES including the utilisation of novel techniques to allow for maximum radical oncological control in the era of SABR and lesser invasive surgery. Methods: First-stage: Carbonfibre pedicle screws planned from L2 to S2AI-Pelvis, aligned, to her patient-specific rods. Radiofrequency ablation of L5 pedicles prior to osteotomy was performed to prevent sarcoma cell seeding. Microscope-assisted thecal sac tumour separation and L5 nerve root dissection was performed. Novel surgical navigation of the ultrasonic bone-cutter assisted inferior L4 and superior S1 endplate osteotomies. Second-stage: Vascular-assisted retroperitoneal approach at L4-S1 was undertaken protecting the great vessels. Completion of osteotomies at L4 and S1 to En-bloc L5: (L4 inferior endplate, L4/5 disc, L5 body, L5/S1 disc and S1 superior endplate). Anterior reconstruction used an expandable PEEK cage obviating the need for a third posterior stage. Reinforced with a patient-specific carbon plate L4-S1 promontory. Results: Patient rehabilitated well and was discharged after 42 days. Cyberknife of 30Gy in 5 fractions was delivered two months post-op. Despite left foot drop, she's walking independently 9 months post-op. Conclusion: These are challenging cases require a truly multi-disciplinary team approach. We share this technique for a dual stage TES and metal-free construct with post adjuvant SABR to achieve maximum local control in spinal oligometastatic disease. This case promotes our modified TES technique in the era of SABR and separation surgery in carefully selected cases.

Radiomic Features From Diffusion-Weighted MRI of Retroperitoneal Soft-Tissue Sarcomas Are Repeatable and Exhibit Change After Radiotherapy.

Background: Size-based assessments are inaccurate indicators of tumor response in soft-tissue sarcoma (STS), motivating the requirement for new response imaging biomarkers for this rare and heterogeneous disease. In this study, we assess the test-retest repeatability of radiomic features from MR diffusion-weighted imaging (DWI) and derived maps of apparent diffusion coefficient (ADC) in retroperitoneal STS and compare baseline repeatability with changes in radiomic features following radiotherapy (RT). Materials and Methods: Thirty patients with retroperitoneal STS received an MR examination prior to treatment, of whom 23/30 were investigated in our repeatability analysis having received repeat baseline examinations and 14/30 patients were investigated in our post-treatment analysis having received an MR examination after completing pre-operative RT. One hundred and seven radiomic features were extracted from the full manually delineated tumor region using PyRadiomics. Test-retest repeatability was assessed using an intraclass correlation coefficient (baseline ICC), and post-radiotherapy variance analysis (post-RT-IMS) was used to compare the change in radiomic feature value to baseline repeatability. Results: For the ADC maps and DWI images, 101 and 102 features demonstrated good baseline repeatability (baseline ICC > 0.85), respectively. Forty-three and 2 features demonstrated both good baseline repeatability and a high post-RT-IMS (>0.85), respectively. Pearson correlation between the baseline ICC and post-RT-IMS was weak (0.432 and 0.133, respectively). Conclusions: The ADC-based radiomic analysis shows better test-retest repeatability compared with features derived from DWI images in STS, and some of these features are sensitive to post-treatment change. However, good repeatability at baseline does not imply sensitivity to post-treatment change.

Therapeutic effect of sodium iodide symporter gene therapy combined with external beam radiotherapy and targeted drugs that inhibit DNA repair.

Adenoviral (AdV) transfer of sodium iodide symporter (NIS) gene has translational potential, but relatively low levels of transduction and subsequent radioisotope uptake limit the efficacy of the approach. In previous studies, we showed that combining NIS gene delivery with external beam radiotherapy (EBRT) and DNA damage repair inhibitors increased viral gene expression and radioiodide uptake. Here, we report the therapeutic efficacy of this strategy. An adenovirus expressing NIS from a telomerase promoter (Ad-hTR-NIS) was cytotoxic combined with relatively high-dose (50 microCi) (131)I therapy and enhanced the efficacy of EBRT combined with low-dose (10 and 25 microCi) (131)I therapy in colorectal and head and neck cancer cells. Combining this approach with ataxia-telangiectasia mutated (ATM) or DNA-dependent protein kinase (DNA-PK) inhibition caused maintenance of double-stranded DNA breaks (DSBs) at 24 hours and increased cytotoxicity on clonogenic assay. When the triplet of NIS-mediated (131)I therapy, EBRT, and DNA-PKi was used in vivo, 90% of mice were tumor-free at 5 weeks. Acute radiation toxicity in the EBRT field was not exacerbated. In contrast, DNA-PKi did not enhance the therapeutic efficacy of EBRT plus adenovirus-mediated HSVtk/ganciclovir (GCV). Therefore, combining NIS gene therapy and EBRT represents an ideal strategy to exploit the therapeutic benefits of novel radiosensitizers.

Descriptive analysis of MRI functional changes occurring during reduced dose radiotherapy for myxoid liposarcomas.

OBJECTIVES: Myxoid liposarcomas (MLS) show enhanced response to radiotherapy due to their distinctive vascular pattern and therefore could be effectively treated with lower radiation doses. This is a descriptive study to explore the use of functional MRI to identify response in a uniform cohort of MLS patients treated with reduced dose radiotherapy. METHODS: 10 patients with MLS were imaged pre-, during, and post-radiotherapy receiving reduced dose radiotherapy and the response to treatment was histopathologically assessed post-radiotherapy. Apparent diffusion coefficient (ADC), T2* relaxation time, volume transfer constant (Ktrans), initial area under the gadolinium curve over 60 s (IAUGC60) and (Gd) were estimated for a central tumour volume. RESULTS: All parameters showed large inter- and intrasubject variabilities. Pre-treatment (Gd), IAUGC60 and Ktrans were significantly different between responders and non-responders. Post-radiotherapy reductions from baseline were demonstrated for T2*, (Gd), IAUGC60 and Ktrans for responders. No statistically significant ADC differences were demonstrated between the two response groups. Significantly greater early tumour volume reductions were observed for responders. CONCLUSIONS: MLS are heterogenous lesions, characterised by a slow gradual contrast-agent uptake. Pre-treatment vascular parameters, early changes to tumour volume, vascular parameters and T2* have potential in identifying response to treatment. The delayed (Gd) is a suitable descriptive parameter, relying simply on T1 measurements. Volume changes precede changes in MLS functionality and could be used to identify early response. ADVANCES IN KNOWLEDGE: MLS are are characterised by slow gradual contrast-agent uptake. Measurement of the delayed contrast-agent uptake (Gd) is simple to implement and able to discriminate response.

Treatments and Outcomes in Oligometastatic Soft Tissue Soft Sarcoma - A Single Centre Retrospective Analysis.

BACKGROUND/AIM: Distinguishing true oligometastatic disease from early polymetastatic disease is vital in patients with soft tissue sarcoma as contemporary treatment strategies differ significantly. Clinical factors such as tumour biology, organ involved, number of lesions, and patient fitness influence clinical decisions. PATIENTS AND METHODS: A retrospective search of a prospective database identified patients with new distant relapse, treated between 2009 and 2012. RESULTS: A total of 223 patients were included, and oligometastases were diagnosed in 81 (36%) patients, which were pulmonary in just over half of cases. These were treated with local therapy in 66 of 89 cases, and 7 patients received subsequent treatment for additional oligometastases. Metastasectomy was the most common treatment modality. A total of 16/66 patients (24%) underwent active surveillance for >6 months prior to local therapy. CONCLUSION: Patients with oligometastatic disease can experience durable disease control with timely multimodality treatment approaches for evolving metastatic disease, where disease biology allows.

Clinical management and outcomes of primary ovarian leiomyosarcoma - Experience from a sarcoma specialist unit.

Ovarian sarcomas account for 1% of all ovarian malignancies and amongst these, primary ovarian leiomyosarcoma is the rarest subtype. Primary ovarian leiomyosarcoma has a very poor prognosis, with less than 20% of patients being alive at 5 years. Only a few cases have been published in the literature and there is very limited knowledge on the clinical behaviour and optimal management of these tumours. We have performed a retrospective analysis of a prospectively maintained database to identify all primary ovarian leiomyosarcoma diagnosed and treated at the Royal Marsden NHS Foundation Trust between 1998 and 2020. Sixteen patients were identified from our database and fifteen were eligible for the analysis. Twelve patients presented with localized disease and underwent initial surgery and three patients had metastatic disease at presentation. Recurrence-free survival post-surgery was 16 months. Eight patients received first-line chemotherapy and four patients received second-line chemotherapy. Two patients had indolent metastatic disease and benefited from local therapies only. The median overall survival in the metastatic setting in our cohort was 51 months, which is consistent with previously published cases. Primary ovarian leiomyosarcoma is an extremely rare malignancy with a poor prognosis. This study is the largest case series of primary ovarian leiomyosarcoma published to date, providing clinically important information regarding survival and metastatic rate as well as treatment outcomes in the metastatic setting.