T2* Imaging Assessment of Neoadjuvant Radiation Therapy Combined With Pharmacological Ascorbate in Extremity Soft-Tissue Sarcomas: A Pilot Study

Background

Extremity soft-tissue sarcomas (STS) are commonly treated with neoadjuvant radiation therapy followed by surgical resection. However, the pathological near-complete response rate is low (9-25%). Noninvasive imaging assessment that predicts treatment response before and during treatment is desirable to optimize treatment regimens. This pilot study aimed to investigate the application of a quantitative MRI parameter, T2*, in assessing neoadjuvant radiation therapy combined with pharmacological ascorbate in extremity STS.

Methods

This prospective cohort study included seven patients diagnosed with extremity STS and scheduled to receive neoadjuvant radiation therapy combined with pharmacological ascorbate. T2* maps were obtained from each patient before treatment (baseline MRI), two weeks after initiating treatment (on-treatment MRI), and before surgery (pre-surgery MRI). The T2* values within the tumor region were transformed into z-scores with respect to the normal- appearing tissue region. The voxel-wise z-scores within the tumor region were thresholded to generate masks representing significantly high (z-score>1.96) and low z-score (z-score<-1.96) voxels. The means of the total z-scores and within each of the significantly high and low z-score mask were computed. Their correlations with percent necrosis from pathological examination were evaluated using Spearman's rank correlation coefficient r. A correlation was considered as moderate or strong when r is higher than 0.6 and 0.8, respectively. A correlation was considered as fair or weak when r is below 0.6.

Results

For the baseline and on-treatment MRIs, the means of the significantly high z-scores of the T2* measurements showed moderate correlations with percent necrosis (r = 0.68 and 0.6; p = 0.11 and 0.24). For the pre-surgery MRI, the means of the total and significantly high z-scores showed strong correlations with percent necrosis (r = 0.8 and 0.9; p = 0.13 and 0.08). Tumor volume and baseline MRI-based percent necrosis showed fair or weak correlations (r = 0.3-0.54; p = 0.24-0.68).

Conclusion

T2* measurements prior to treatment, two weeks after initiating treatment, and before surgery showed moderate to strong correlations with percent necrosis. These results support the potential for using T2* mapping to predict and assess response to neoadjuvant radiation therapy combined with pharmacological ascorbate in extremity STS. Level of Evidence: IV.

Efficacy and Safety of Trans-Arterial Yttrium-90 Radioembolization in Patients with Unresectable Liver-Dominant Metastatic or Primary Hepatic Soft Tissue Sarcomas

Simple Summary

Sarcomas of the liver are a rare and aggressive group of malignancies for which surgery is the preferred treatment modality even though most patients are not surgical candidates and receive chemotherapy with poor outcomes. In these cases, trans-arterial liver-directed therapies are emerging as a new treatment option. Among these, radioembolization is a promising but understudied treatment option. In radioembolization, microbeads conjugated to a radioactive drug are injected into the blood vessels, nourishing the cancers and leading to cell death and tumor shrinkage. In this study, we retrospectively analyzed 35 patients with liver sarcomas receiving radioembolization at our institution. We found that those with disease control in the liver 6 months after the procedure had longer overall survival as well as patients with a liver progression-free interval post-procedure equal to or greater than 9 months. Patients with good performance status and normal liver function at baseline also had longer survival. The most common adverse reactions were nausea, fatigue, abdominal pain, and mild reversible abnormalities in liver function tests. Overall, our results suggest that radioembolization might be a safe and effective treatment option for patients with unresectable liver sarcomas.

Abstract

Patients with liver-dominant metastatic or primary hepatic soft tissue sarcomas (STS) have poor prognosis. Surgery can prolong survival, but most patients are not surgical candidates, and treatment response is limited with systemic chemotherapy. Liver-directed therapies have been increasingly employed in this setting, and Yttrium-90 trans-arterial radioembolization (TARE) is an understudied yet promising treatment option. This is a retrospective analysis of 35 patients with metastatic or primary hepatic STS who underwent TARE at a single institution between 2006 and 2020. The primary outcomes that were measured were overall survival (OS), liver progression-free survival (LPFS), and radiologic tumor response. Clinical and biochemical toxicities were assessed 3 months after the procedure. Median OS was 20 months (95% CI: 13.9–26.1 months), while median LPFS was 9 months (95% CI: 6.2–11.8 months). The objective response rate was 56.7%, and the disease control rate was 80.0% by mRECIST at 3 months. The following correlated with better OS post-TARE: liver disease control (DC) at 6 months (median OS: 40 vs. 17 months, p = 0.007); LPFS ≥ 9 months (median OS: 50 vs. 8 months, p < 0.0001); ECOG status 0–1 vs. 2 (median OS: 22 vs. 6 months, p = 0.042); CTP class A vs. B (median OS: 22 vs. 6 months, p = 0.018); and TACE post-progression (median OS: 99 vs. 16 months, p = 0.003). The absence of metastases at diagnosis was correlated with higher median LPFS (7 vs. 1 months, p = 0.036). Two grade 4 (5.7%) and ten grade 3 (28.6%) laboratory toxicities were identified at 3 months. There was one case of radioembolization-induced liver disease and two cases of radiation-induced peptic ulcer disease. We concluded that TARE could be an effective and safe treatment option for patients with metastatic or primary hepatic STS with good tumor response rates, low incidence of severe toxicity, and longer survival in patients with liver disease control post-TARE.

Predicting distant metastases in soft-tissue sarcomas from PET-CT scans using constrained hierarchical multi-modality feature learning

Objective.Positron emission tomography-computed tomography (PET-CT) is regarded as the imaging modality of choice for the management of soft-tissue sarcomas (STSs). Distant metastases (DM) are the leading cause of death in STS patients and early detection is important to effectively manage tumors with surgery, radiotherapy and chemotherapy. In this study, we aim to early detect DM in patients with STS using their PET-CT data.Approach.We derive a new convolutional neural network method for early DM detection. The novelty of our method is the introduction of a constrained hierarchical multi-modality feature learning approach to integrate functional imaging (PET) features with anatomical imaging (CT) features. In addition, we removed the reliance on manual input, e.g. tumor delineation, for extracting imaging features.Main results.Our experimental results on a well-established benchmark PET-CT dataset show that our method achieved the highest accuracy (0.896) and AUC (0.903) scores when compared to the state-of-the-art methods (unpaired student's t-testp-value < 0.05).Significance.Our method could be an effective and supportive tool to aid physicians in tumor quantification and in identifying image biomarkers for cancer treatment.

A comparison of clinical outcomes between additional excision after unplanned and planned excisions in patients with soft-tissue sarcoma of the limb : a propensity matching cohort study

AIMS

Patients with soft-tissue sarcoma (STS) who undergo unplanned excision (UE) are reported to have worse outcomes than those who undergo planned excision (PE). However, others have reported that patients who undergo UE may have similar or improved outcomes. These discrepancies are likely to be due to differences in characteristics between the two groups of patients. The aim of the study is to compare patients who underwent UE and PE using propensity score matching, by analyzing data from the Japanese Bone and Soft Tissue Tumor (BSTT) registry.

METHODS

Data from 2006 to 2016 was obtained from the BSTT registry. Only patients with STS of the limb were included in the study. Patients with distant metastasis at the initial presentation and patients with dermatofibrosarcoma protuberans and well-differentiated liposarcoma were excluded from the study.

RESULTS

A total of 4,483 patients with STS of the limb were identified before propensity score matching. There were 355 patients who underwent UE and 4,128 patients who underwent PE. The five-year disease-specific survival (DSS) rate was significantly better in the patients who received additional excision after UE than in those who underwent PE. There was no significant difference in local recurrence-free survival (LRFS) between the two groups. After propensity score matching, a new cohort of 355 patients was created for both PE and UE groups, in which baseline covariates were appropriately balanced. Reconstruction after tumour excision was frequently performed in patients who underwent additional excision after UE. There were no significant differences in DSS and LRFS between the patients who underwent PE and those who had an additional excision after UE.

CONCLUSION

Using propensity score matching, patients with STS of the limb who underwent additional excision after UE did not experience higher mortality and local failure than those who underwent PE. Reconstruction may be necessary when additional excision is performed. Cite this article: Bone Joint J 2021;103-B(12):1809-1814.

Primary Renal Synovial Sarcoma Presenting as Haemorrhagic Shock: A Rare Presentation

Primary synovial sarcoma (PSS) of the kidney is considered the rarest type of all renal sarcomas with specific chromosomal translocation t (X; 18) (p11.2; q11.2). We report the case of a 65-year-old man with no medical conditions who presented to the emergency department with sudden severe right flank pain associated with haemodynamic instability and haemorrhagic shock. Computed tomography (CT) of the abdomen and pelvis revealed a right renal mass. A right open radical nephrectomy was performed. Histopathology revealed a monophasic synovial sarcoma. The patient received six cycles of docetaxel and gemcitabine as adjuvant chemotherapy. No sign of recurrence was seen on a follow-up CT urogram. This rare tumour often presents atypically, and clear guidelines regarding appropriate treatment are lacking. Our case showed that treatment with docetaxel/gemcitabine after an open radical nephrectomy is promising.

Detection and utility of cell-free and circulating tumour DNA in bone and soft-tissue sarcomas

Aims

Cell-free DNA (cfDNA) and circulating tumour DNA (ctDNA) are used for prognostication and monitoring in patients with carcinomas, but their utility is unclear in sarcomas. The objectives of this pilot study were to explore the prognostic significance of cfDNA and investigate whether tumour-specific alterations can be detected in the circulation of sarcoma patients.

Methods

Matched tumour and blood were collected from 64 sarcoma patients (n = 70 samples) prior to resection of the primary tumour (n = 57) or disease recurrence (n = 7). DNA was isolated from plasma, quantified, and analyzed for cfDNA. A subset of cases (n = 6) underwent whole exome sequencing to identify tumour-specific alterations used to detect ctDNA using digital droplet polymerase chain reaction (ddPCR).

Results

Cell-free was present in 69 of 70 samples above 0.5 ng/ml. Improved disease-free survival was found for patients with lower cfDNA levels (90% vs 48% at one-year for ≤ 6 ng/ml and > 6 ng/ml, respectively; p = 0.005). Digital droplet PCR was performed as a pilot study and mutant alleles were detectable at 0.5% to 2.5% of the wild type genome, and at a level of 0.25 ng tumour DNA. Tumour-specific alterations (ctDNA) were found in five of six cases.

Conclusion

This work demonstrates the feasibility and potential utility of cfDNA and ctDNA as biomarkers for bone and soft-tissue sarcomas, despite the lack of recurrent genomic alterations. A larger study is required to validate these findings.

Cite this article: Bone Joint Res 2021;10(9):602–610.

Development and External Validation of Deep-Learning-Based Tumor Grading Models in Soft-Tissue Sarcoma Patients Using MR Imaging

BACKGROUND

In patients with soft-tissue sarcomas, tumor grading constitutes a decisive factor to determine the best treatment decision. Tumor grading is obtained by pathological work-up after focal biopsies. Deep learning (DL)-based imaging analysis may pose an alternative way to characterize STS tissue. In this work, we sought to non-invasively differentiate tumor grading into low-grade (G1) and high-grade (G2/G3) STS using DL techniques based on MR-imaging.

METHODS

Contrast-enhanced T1-weighted fat-saturated (T1FSGd) MRI sequences and fat-saturated T2-weighted (T2FS) sequences were collected from two independent retrospective cohorts (training: 148 patients, testing: 158 patients). Tumor grading was determined following the French Federation of Cancer Centers Sarcoma Group in pre-therapeutic biopsies. DL models were developed using transfer learning based on the DenseNet 161 architecture.

RESULTS

The T1FSGd and T2FS-based DL models achieved area under the receiver operator characteristic curve (AUC) values of 0.75 and 0.76 on the test cohort, respectively. T1FSGd achieved the best F1-score of all models (0.90). The T2FS-based DL model was able to significantly risk-stratify for overall survival. Attention maps revealed relevant features within the tumor volume and in border regions.

CONCLUSIONS

MRI-based DL models are capable of predicting tumor grading with good reproducibility in external validation.

Prognostic Assessment in High-Grade Soft-Tissue Sarcoma Patients: A Comparison of Semantic Image Analysis and Radiomics

BACKGROUND

In patients with soft-tissue sarcomas of the extremities, the treatment decision is currently regularly based on tumor grading and size. The imaging-based analysis may pose an alternative way to stratify patients' risk. In this work, we compared the value of MRI-based radiomics with expert-derived semantic imaging features for the prediction of overall survival (OS).

METHODS

Fat-saturated T2-weighted sequences (T2FS) and contrast-enhanced T1-weighted fat-saturated (T1FSGd) sequences were collected from two independent retrospective cohorts (training: 108 patients; testing: 71 patients). After preprocessing, 105 radiomic features were extracted. Semantic imaging features were determined by three independent radiologists. Three machine learning techniques (elastic net regression (ENR), least absolute shrinkage and selection operator, and random survival forest) were compared to predict OS.

RESULTS

ENR models achieved the best predictive performance. Histologies and clinical staging differed significantly between both cohorts. The semantic prognostic model achieved a predictive performance with a C-index of 0.58 within the test set. This was worse compared to a clinical staging system (C-index: 0.61) and the radiomic models (C-indices: T1FSGd: 0.64, T2FS: 0.63). Both radiomic models achieved significant patient stratification.

CONCLUSIONS

T2FS and T1FSGd-based radiomic models outperformed semantic imaging features for prognostic assessment.

Patterns of Radiotherapy Use and Outcomes in Head and Neck Soft-Tissue Sarcoma in a National Cohort

OBJECTIVES/HYPOTHESIS

We used the National Cancer Database to identify the patterns of care and prognostic factors in adult patients with head and neck soft-tissue sarcoma (HNSTS).

STUDY DESIGN

Retrospective cohort analysis.

METHODS

Using the National Cancer Database, we identified patients age ≥ 18 years who were diagnosed with HNSTS between 2004 and 2013. Both χ² and multivariate logistic regression were used to identify factors associated with radiation therapy (RT) utilization. Kaplan-Meier methods were used to estimate overall survival (OS) and Cox proportional regression was used to determine significant contributors to OS.

RESULTS

Our final cohort included 1,282 patients (682 treated with surgery only, 199 treated with RT only, and 401 treated with surgery and RT). Patients with younger age, poor tumor grade, rhabdomyosarcoma histology, and chemotherapy treatment were more likely to receive RT alone without surgery. Among the 1,083 surgical patients, RT utilization was associated with positive margins (odds ratio [OR]: 2.18, 95% confidence interval [CI]: 1.36-3.48), poor grade (OR: 2.92, 95% CI: 1.95-4.38), and chemotherapy use (OR: 1.78, 95% CI: 1.15-2.76). Radiotherapy utilization among surgical patients was not affected by demographic factors (age, sex, or ethnicity) or treatment institution (academic or community). For surgical patients, poor grade, large tumor size, and rhabdomyosarcoma histology were associated with worse OS on multivariate analysis.

CONCLUSIONS

In this analysis of HNSTS, younger patients with poor tumor grade and rhabdomyosarcoma histology were more likely to receive RT without surgery. Among surgical patients, adjuvant RT was more likely to be used for positive margins and poor grade, with no demographic disparities identified. Poor grade and rhabdomyosarcoma histology were negative prognostic factors for surgical patients.

LEVEL OF EVIDENCE

NA Laryngoscope, 130:120-127, 2020.

Recombinant Adenovirus-p53 Gene Therapy for Advanced Unresectable Soft-Tissue Sarcomas

Patients with unresectable advanced soft-tissue sarcomas (STS) receiving radiotherapy or/and chemotherapy still have a poor prognosis. This study aimed to evaluate retrospectively the efficacy and safety of recombinant adenovirus-p53 (rAd-p53) gene therapy combined with radiotherapy and hyperthermia for advanced STS. A total of 71 patients with advanced unresectable STS treated at the authors' center from April 2007 to November 2014 were included. Of these 71 patients, 36 cases received rAd-p53 therapy combined with radiotherapy and hyperthermia (p53 group), while 35 cases received radiotherapy and hyperthermia alone (control group). Short-term therapeutic efficacies, long-term survival outcomes, and adverse events were evaluated and compared between groups. Compared to the control group, the p53 group had a significantly higher disease control rate (83.33% vs. 54.29%; p = 0.008) and a lower progressive disease rate (16.67% vs. 45.71%; p = 0.018). In addition, rAd-p53 treatment significantly improved the progression-free survival and overall survival of STS patients. Cox regression indicated that rAd-p53 treatment significantly reduced the risks for disease progression or death event for STS patients. Furthermore, there was no significant difference in all adverse events, except for transient fever, which occurred in 89% of patients with rAd-p53 therapy. rAd-p53 combined with radiotherapy and hyperthermia can effectively improve the therapeutic efficacy and survival outcomes in patients with advanced unresectable STS, providing a new therapeutic strategy.

BO-1055, a novel DNA cross-linking agent with remarkable low myelotoxicity shows potent activity in sarcoma models

DNA damaging agents cause rapid shrinkage of tumors and form the basis of chemotherapy for sarcomas despite significant toxicities. Drugs having superior efficacy and wider therapeutic windows are needed to improve patient outcomes. We used cell proliferation and apoptosis assays in sarcoma cell lines and benign cells; γ-H2AX expression, comet assay, immunoblot analyses and drug combination studies in vitro and in patient derived xenograft (PDX) models. BO-1055 caused apoptosis and cell death in a concentration and time dependent manner in sarcoma cell lines. BO-1055 had potent activity (submicromolar IC50) against Ewing sarcoma and rhabdomyosarcoma, intermediate activity in DSRCT (IC50 = 2-3μM) and very weak activity in osteosarcoma (IC50 >10μM) cell lines. BO-1055 exhibited a wide therapeutic window compared to other DNA damaging drugs. BO-1055 induced more DNA double strand breaks and γH2AX expression in cancer cells compared to benign cells. BO-1055 showed inhibition of tumor growth in A673 xenografts and caused tumor regression in cyclophosphamide resistant patient-derived Ewing sarcoma xenografts and A204 xenografts. Combination of BO-1055 and irinotecan demonstrated synergism in Ewing sarcoma PDX models. Potent activity on sarcoma cells and its relative lack of toxicity presents a strong rationale for further development of BO-1055 as a therapeutic agent.

Controversies and consensus of neoadjuvant chemotherapy in soft-tissue sarcomas

Together with surgery and radiotherapy, systemic treatment with cytotoxic chemotherapy and molecular targeted agents is one of the main therapeutic pillars in the treatment of soft-tissue sarcomas and is the mainstay of treatment in patients with advanced or metastatic disease. Unlike other more common malignancies such as breast and colorectal cancer, the role of chemotherapy when used in the adjuvant setting in soft-tissue sarcomas is less well defined. Results from prior studies have been conflicting, in part due to the heterogeneity and rarity of the disease, and large-scale meta-analysis has been performed to address this issue. Neoadjuvant chemotherapy, defined as the use of chemotherapy before definitive treatment with surgery or radiotherapy, has distinct theoretical and practical advantages, which can potentially be beneficial to the patient. However, the currently available evidence to support its use is even more scarce. In this review article, we describe the current established data behind the use of adjuvant chemotherapy in selected patients with localised soft-tissue sarcomas and, through extrapolation of available data, discuss the potential role of it when used in the upfront setting.

Epidemiological study of soft-tissue sarcomas in Ireland

Soft‐tissue sarcomas (STS) account for 1% of adult and 7% of pediatric malignancies. Histopathology and classification of these rare tumors requires further refinements. The aim of this paper is to describe the current incidence and survival of STS from 1994 to 2012 in Ireland and compare these with comparably coded international published reports. This is a retrospective, population study based on the data from the National Cancer Registry of Ireland (NCRI). Incidence and relative survival rates for STS in Ireland were generated. Incidence of STS based on gender, age and anatomical location was examined. Annual mean incidence rate (European Age Standardized) in Ireland between 1994 and 2012 was 4.48 ± 0.15 per 100,000 person‐years. The overall relative 5‐year survival rate of STS for the period 1994–2011 in Ireland was 56%, which was similar to that reported in the U.K. but lower than in most of Europe and U.S.A. Survival rate fluctuated over the period examined, declining slightly in females but showing an increase in males. STS incidence trends in Ireland were comparable to international reports. Survival trends of STS were significantly different between Ireland and other European countries, requiring further study to understand causation.

Gemcitabine in combination with paclitaxel for advanced soft-tissue sarcomas

A limited number of chemotherapeutic agents have been found to be active against advanced soft-tissue sarcomas (STSs), particularly sarcomas that have progressed following doxorubicin treatment. The aim of this retrospective study was to determine the response to treatment with gemcitabine plus paclitaxel in patients with STSs. Data were collected on all patients with advanced non-resectable STS who were treated with a fixed dose 700 mg/m² gemcitabine in combination with 70 mg/m² paclitaxel on days 1 and 8 every 3 weeks. A total of 30 patients were included, with a median age of 56.4 years (range, 40-70 years). The gemcitabine/paclitaxel combination was well tolerated, with an overall response in 27% and a clinical benefit in 57% of the patients. The median progression-free survival was 6.1 months and the overall survival was 14.3 months. In conclusion, gemcitabine plus paclitaxel was found to be tolerable and effective in patients with advanced STSs.