Adjuvant chemotherapy and postoperative radiotherapy in high-risk soft tissue sarcoma patients defined by biological risk factors-A Scandinavian Sarcoma Group study (SSG XX)

Non-invasive monitoring of neoadjuvant radiation therapy response in soft tissue sarcomas by multiparametric MRI and quantification of circulating tumor DNA-A study protocol

BACKGROUND

Wide resection remains the cornerstone of localized soft-tissue sarcomas (STS) treatment. Neoadjuvant radiation therapy (NRT) may decrease the risk of local recurrences; however, its effectiveness for different histological STS subtypes has not been systematically investigated. The proposed prospective study evaluates the NRT response in STS using liquid biopsies and the correlation of multiparametric magnetic resonance imaging (mpMRI) with histopathology and immunohistochemistry.

METHODS

Patients with localized high-grade STS, who qualify for NRT, are included in this study.

LIQUID BIOPSIES

Quantification of circulating tumor DNA (ctDNA) in patient blood samples is performed by targeted next-generation sequencing. Soft-tissue sarcoma subtype-specific panel sequencing in combination with patient-specific exome sequencing allows the detection of individual structural variants and point mutations. Circulating free DNA is isolated from peritherapeutically collected patient plasma samples and ctDNA quantified therein. Identification of breakpoints is carried out using FACTERA. Bioinformatic analysis is performed using samtools, picard, fgbio, and the MIRACUM Pipeline.

MPMRI

Combination of conventional MRI sequences with diffusion-weighted imaging, intravoxel-incoherent motion, and dynamic contrast enhancement. Multiparametric MRI is performed before, during, and after NRT. We aim to correlate mpMRI data with the resected specimen's macroscopical, histological, and immunohistochemical findings.

RESULTS

Preliminary data support the notion that quantification of ctDNA in combination with tumor mass characterization through co-registration of mpMRI and histopathology can predict NRT response of STS.

CLINICAL RELEVANCE

The methods presented in this prospective study are necessary to assess therapy response in heterogeneous tumors and lay the foundation of future patient- and tumor-specific therapy concepts. These methods can be applied to various tumor entities. Thus, the participation and support of a wider group of oncologic surgeons are needed to validate these findings on a larger patient cohort.

Immune-cell infiltration in high-grade soft tissue sarcomas; prognostic implications of tumor-associated macrophages and B-cells

BACKGROUND

Soft tissue sarcomas are rare, morphologically, and genetically heterogenous. Though the tumors display abundant tumor stroma with infiltrating immune cells, the prognostic impact of various immunologic markers in sarcoma remains poorly defined. We aimed to characterize the immune landscape of a treatment-naïve cohort of soft tissue sarcoma of the extremities and the trunk wall with correlations to metastasis-free survival.

MATERIALS AND METHODS

We surveyed immunohistochemical expression patterns for CD163, CD20, CD3, CD8, and FOXP3 in 134 adult high-grade leiomyosarcomas, liposarcomas, and synovial sarcomas.

RESULTS

Macrophages outnumbered tumor-infiltrating lymphocytes. High CD163 infiltration was identified in 49% of the tumors and was overrepresented (66%) in leiomyosarcoma compared to liposarcoma (46%) and synovial sarcoma (9%). Tumor-grade also correlated with CD163 positivity with high expression in 53% of the high-grade lesions and 28% in low-grade tumors. Infiltrating CD3, CD8 and FOXP3-positive T-cells were significantly more prevalent in leiomyosarcomas than in liposarcomas/synovial sarcomas. CD20⁺ B-cells were identified only in 14% of the STS. Correlation to established prognostic factors revealed a correlation between CD163⁺ macrophages and necrosis and predicted an increased risk of metastases. No correlation between CD20⁺ B-cells and known prognostic factors could be established, though CD20⁺ B-cells infiltration predicted improved overall survival.

CONCLUSION

We confirm that tumor-infiltrating macrophages outnumber tumor-infiltrating lymphocytes in soft tissue sarcoma and signify an increased risk of metastasis. CD20⁺ B-cells are scarce in STS and correlate to improved survival. To date, immunotherapeutic strategies directed against T-cells have shown limited effect in soft tissue sarcoma. Our observations suggest that immunomodulatory agents focusing on macrophages may be worthwhile for further investigations in this tumor type. Further studies exploring the prognostic and predictive significance of CD20⁺ B cells are warranted.

Soft tissue sarcoma: intravoxel incoherent motion and diffusion kurtosis imaging parameters correlate with the histological grade and Ki-67 expression

BACKGROUND

Accurate prediction of the histological grade and Ki-67 expression of soft tissue sarcoma (STS) before surgery is essential for the subsequent diagnosis, treatment, and prognostic evaluation of patients.

PURPOSE

To evaluate intravoxel incoherent motion (IVIM) and diffusion kurtosis imaging (DKI) in predicting the histological grade and Ki-67 expression of STS.

MATERIAL AND METHODS

A total of 40 patients underwent 3-T MRI, including conventional sequences; IVIM and DKI parameters were obtained. All patients were divided into a low-grade (grade 1 and grade 2) group and a high-grade (grade 3) group through pathological analysis. Ki-67 expression of each lesion was calculated. Chi-square test, independent sample t-test, Mann-Whitney U test, Pearson, Spearman, and receiver operating characteristic curve analysis were performed.

RESULTS

There were 17 patients in the low-grade group and 23 in the high-grade group. Ki-67 expression was in the range of 10%-80%. D value was inversely correlated with Ki-67 expression. MK value showed a moderate positive correlation with Ki-67 expression. Regarding histological grading, only the peritumoral enhancement was statistically different between low- and high-grade STS on conventional MRI (P=0.024). The high-grade group had significantly higher MK value and lower D and MD value than the low-grade group. MK value showed the best diagnostic performance. The combination of MK and MD yielded the highest specificity (88.24%), and the combination of D, MK, and MD yielded the best area under the curve value (0.841) and sensitivity (95.65%).

CONCLUSION

IVIM and DKI parameters were correlated with Ki-67 expression and could help differentiate between low- and high-grade STS.

Real-world evidence on perioperative chemotherapy in localized soft tissue sarcoma of the extremities and trunk wall; a population-based study

BACKGROUND

Data from the real-world setting on perioperative chemotherapy in high-risk, localized soft tissue sarcoma (STS) is limited. Real-world data (RWD) includes data derived from patients treated outside clinical trials and often captures long-term follow-up not recorded in clinical trials. The aim of this study was to provide population-based, real-world evidence on perioperative chemotherapy in localized STS.

MATERIAL AND METHODS

Adult patients with localized STS in the extremities or trunk wall treated at Oslo University Hospital, Oslo, Norway from 1998 to 2017 were included in the study. Data were extracted from a prospectively maintained database, supplemented by retrospective review of medical records.

RESULTS

The total study cohort included 806 patients, of whom 154 (19%) received perioperative chemotherapy. A regimen with anthracycline and ifosfamide was given in 141 of 154 cases (92%). During long-term follow-up two patients developed secondary malignancies, cardiac toxicity was registered in 11 patients (7%) and renal toxicity in 12 patients (8%). Seventy-one of 154 patients (46%) were treated outside of clinical trials and constituted the RWD cohort. The median age at surgery was slightly lower and there were more synovial sarcomas and fewer myxofibrosarcomas in the RWD cohort. No difference in chemotherapy dose intensity was observed. The estimated 5-year metastasis-free survival (MFS) in all patients receiving perioperative chemotherapy was 58%. In the RWD cohort 5-year MFS was 53% and in the clinical study cohort 61% (HR 1.24; 95% CI 0.77-2.00).

CONCLUSION

Long-term outcome after perioperative chemotherapy was comparable for patients treated in routine clinical practice to those in clinical trials. Secondary malignancy and cardiac toxicity were observed. The risk of serious late side effects should be included in the decision process on perioperative chemotherapy.

Does the primary soft-tissue sarcoma configuration predict configuration of recurrent tumors on magnetic resonance imaging?

BACKGROUND

Soft-tissue sarcomas (STS) are rare malignancies of the soft tissue.

PURPOSE

To assess whether the magnetic resonance imaging (MRI) configuration of primary STS can predict the configuration of a recurring tumor and whether the MRI configuration of multiple recurrences differs in one and the same patient.

MATERIAL AND METHODS

Thirty-nine patients with histologically proven recurrent STS were included in this retrospective study and underwent pre- and post-treatment MRI. Three main configurations of primary and recurrent tumors were identified: polycyclic/multilobulated; ovoid/nodular; and streaky.

RESULTS

Sixty recurrent lesions were detected: 34 ovoid/nodular; 15 polycyclic/multilobulated; and 11 streaky. Five recurrences were multifocal and eight were bifocal. Of 39 patients, 28 (71.8%) presented one recurrence within the MRI follow-up period (P = 0.006); in 10 patients (25.6%), up to three different configurations of recurring STS were identified in one patient. Recurrences of polycyclic/multilobulated primaries were mostly ovoid/nodular (48%; P = 0.003) or polycyclic/multilobulated (37%; P = 0.014), and recurring ovoid/nodular STS significantly most often showed the same configuration as the primary tumor (85%; P < 0.001). Primary STS with a streaky configuration recurred in all three configurations in roughly equal proportions. Homogeneity/heterogeneity and tumor borders are significantly associated with the configuration of recurrences.

CONCLUSION

Primary STS configuration may help predict recurrent tumor configuration when the primary STS had a polycyclic/multilobulated or ovoid/nodular configuration. However, recurrent STS configuration can also differ from primary STS configuration, especially when the primary STS had a streaky configuration, rendering recurrent STS difficult to predict. Different configurations of recurrent STS in one and the same patient are common.

Adult Soft-Tissue Sarcomas of the Extremities

➤

Soft-tissue sarcomas (STS) in adults comprise a heterogeneous group of tumors of mesenchymal origin that share similar biological patterns of local tumor growth and metastatic dissemination.

➤

The judicious use of imaging studies, biopsy techniques, and pathological evaluations is essential for accurate diagnosis and for planning treatment strategy.

➤

Wide local resection and radiation therapy form the cornerstone of management of high-grade STS. The role of adjuvant radiation therapy is questionable in the management of small (≤5 cm) superficial lesions that can be resected with negative margins. Chemotherapy given to patients who have nonmetastatic, high-grade STS results in varying benefit in terms of local tumor control and overall survival.

➤

Coordinated care by a multidisciplinary team of trained surgeons, medical oncologists, radiologists, radiation oncologists, and pathologists has been documented to improve local tumor control and the overall survival of patients with STS.

➤

Although considerable progress in tumor diagnostics and targeted therapies has been made over the past 2 decades, recommendations and controversies relating to tumor imaging and margins of resection have not changed.

Neoadjuvant chemotherapy in high-risk soft tissue sarcomas: A Sarculator-based risk stratification analysis of the ISG-STS 1001 randomized trial

BACKGROUND

The value of neoadjuvant chemotherapy in soft tissue sarcoma (STS) is not completely understood. This study investigated the benefit of neoadjuvant chemotherapy according to prognostic stratification based on the Sarculator nomogram for STS.

METHODS

This study analyzed data from ISG-STS 1001, a randomized study that tested 3 cycles of neoadjuvant anthracycline plus ifosfamide (AI) or histology-tailored (HT) chemotherapy in adult patients with STS. The 10-year predicted overall survival (pr-OS) was estimated with the Sarculator and was stratified into higher (10-year pr-OS < 60%) and lower risk subgroups (10-year pr-OS ≥ 60%).

RESULTS

The median pr-OS was 0.63 (interquartile range [IQR], 0.51-0.72) for the entire study population, 0.62 (IQR, 0.51-0.70) for the AI arm, and 0.64 (IQR, 0.51-0.73) for the HT arm. Three- and 5-year overall survival (OS) were 0.86 (95% confidence interval [CI], 0.82-0.93) and 0.81 (95% CI, 0.71-0.86) in lower risk patients and 0.69 (95% CI, 0.70-0.85) and 0.59 (95% CI, 0.51-0.72) in the higher risk patients (log-rank test, P = .004). In higher risk patients, the 3- and 5-year Sarculator-predicted and study-observed OS rates were 0.68 and 0.58, respectively, and 0.85 and 0.66, respectively, in the AI arm (P = .04); the corresponding figures in the HT arm were 0.69 and 0.60, respectively, and 0.69 and 0.55, respectively (P > .99). In lower risk patients, the 3- and 5-year Sarculator-predicted and study-observed OS rates were 0.85 and 0.80, respectively, and 0.89 and 0.82, respectively, in the AI arm (P = .507); the corresponding figures in the HT arm were 0.87 and 0.81, respectively, and 0.86 and 0.74, respectively (P = .105).

CONCLUSIONS

High-risk patients treated with AI performed better than predicted, and this adds to the evidence for the efficacy of neoadjuvant AI in STS.

LAY SUMMARY

People affected by soft tissue sarcomas of the extremities and trunk wall are at some risk of developing metastasis after surgery. Preoperative or postoperative chemotherapy has been tested in clinical trials to reduce the chances of distant metastasis. However, study findings have not been conclusive. This study stratified the risk of metastasis for people affected by sarcomas who were included in a clinical trial testing neoadjuvant chemotherapy. Exploiting the prognostic nomogram Sarculator, it found a benefit for chemotherapy when the predicted risk, based on patient and tumor characteristics, was high.

Undifferentiated Small Round Cell Sarcoma of the Postcricoid Region of the Hypopharynx: A Rare Case Report and Review of the Literature

Undifferentiated small round cell sarcoma (USRCS) is a rare malignant tumor. No reports about USRCS of the postcricoid region of the hypopharynx are available, and its clinical features and treatment guidelines remain undefined. We report a case of USRCS of the postcricoid region of the hypopharynx with treatment of surgery and radiotherapy. A 50-year-old man presented with a 4.9 cm x 3.7 cm tumor in the postcricoid region of the hypopharynx. It was diagnosed as USRCS. The tumor showed small round cells and positive immunoexpression of CD56, Cyclin D1, TLE1 and CD99, but no rearrangement or fusion of EWSR1, SS18, CIC, and BCOR. The patient underwent radiotherapy after surgery, without signs of tumor progression and metastasis at the 9-month follow-up. In conclusion, USRCS of postcricoid region of hypopharyngeal is ultra-rare. To make diagnosis, pathological examination is necessary. Surgery followed by radiotherapy might offer an optional treatment for USCRS.

Late Local Recurrence and Metastasis in Soft Tissue Sarcoma of the Extremities and Trunk Wall: Better Outcome After Treatment of Late Events Compared with Early

Background

Approximately 80% of soft tissue sarcoma (STS) recurrences, local and metastatic disease, are diagnosed within the first 3 years after primary diagnosis and treatment. Recurrences, however, can present after a longer period of remission. Our goal was to identify factors that may predict the risk of late recurrence.

Methods

We identified 677 patients with STS of the extremities and trunk wall from a population-based sarcoma register. Of these, 377 patients were alive and event-free at 3 years and were included for analysis of possible risk factors for late recurrence.

Results

Fifty-five of 377 (15%) patients developed late recurrence: 23 local recurrence, 21 metastasis, and 11 both manifestations. With R0 wide surgical margin as reference, R0 marginal (hazard ratio [HR] 2.6; p = 0.02) and R1 (HR 5.0; p = 0.005) margins were risk factors for late local recurrence. Malignancy grade (HR 8.3; p = 0.04) and R0 marginal surgical margin (HR 2.3; p = 0.04) were risk factors for late metastasis. We could not find a statistically significant correlation of late recurrence with many of the generally known risk factors for local recurrence and metastasis in STS. Outcome after treatment of late recurrences was better compared with outcome after treatment of early events.

Conclusions

Late recurrences, albeit relatively rare, do occur. Outcome after treatment was good compared with outcome after early events. Long surveillance of all patients with high-grade STS, especially if R0 wide surgical margin is not achieved in the primary treatment, appear to be well justified.

Supplementary Information

The online version contains supplementary material available at 10.1245/s10434-021-09942-8.

PBA2, a novel compound, enhances radiosensitivity in various carcinoma cells by activating the p53 pathway in vitro and in vivo

Radiotherapy is the main method used to treat human carcinoma; however, certain types of carcinomas are radiation-insensitive. The present study aimed to explore whether a novel compound, PBA2, could enhance the radiosensitivity of various carcinoma cells in vitro and in vivo, and investigate its underlying mechanism. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to assess the cytotoxicity of PBA2. Colony formation assays were used to observe the radiosensitivity effect of PBA2 in vitro. Cell cycle distributions and cell apoptosis were estimated using flow cytometry. Comet assays and Immunofluorescence assays were used to analyze DNA damage. The intracellular RNA was extracted and analyzed by sequencing. Western blotting was used to determine protein levels. A stable cell line with TP53 (encoding p53) knockdown was constructed by cell transfection. A mouse xenograft model was used to assess the radiosensitivity effect of PBA2 in vivo. We found that PBA2 at a low concentration (0.1 μM) enhanced radiosensitivity in various carcinoma cells, including CNE1, MG63, KB, HEP2, GLC82, and SMMC7221, in vitro. Combined with PBA2, radiation induced significant cell apoptosis in CNE1 and MG63 cells, accompanied by increased DNA damage, but did not affect cell cycle arrest. Mechanistically, PBA2 promoted p53 expression significantly; however, when p53 was mutated, functionally impaired, or knocked down, PBA2 could not enhance the radiosensitivity of these cells. Additionally, the combination of PBA2 and radiation reduced the tumor volume and tumor weight in CNE1 xenograft models significantly, without obvious toxicities. Our results demonstrated that PBA2 enhanced the radiosensitivity of various carcinoma cells in vitro and in vivo. The underlying mechanism might involve increasing DNA damage and cell apoptosis via activating the p53 pathway.

Preoperative accelerated radiotherapy combined with chemotherapy in a defined cohort of patients with high risk soft tissue sarcoma: a Scandinavian Sarcoma Group study

Background

We recently reported outcomes from a Scandinavian Sarcoma Group adjuvant study (SSG XX group A) conducted on localized and operable high risk soft tissue sarcoma (STS) of the extremities and trunk wall. SSG XX, group B, comprised of patients in a defined cohort with locally advanced STS considered at high risk for intralesional surgery. These patients received preoperative accelerated radiotherapy, together with neoadjuvant and adjuvant chemotherapy. Herein we report the results of this group B.

Methods

Twenty patients with high-grade, locally advanced and deep STS located in lower extremities (n = 12), upper extremities (5) or trunk wall (3) were included. The median age was 59 years and 14 patients were males. The treatment regimen consisted of 6 cycles of doxorubicin (60 mg/m²) and ifosfamide (6 g/m²), with three cycles given neoadjuvantly, and preoperative radiotherapy (1, 8 Gyx2/daily to 36 Gy) between cycles 2 and 3. After a repeated MRI surgery was then conducted, and the remaining 3 chemotherapy cycles were given postoperatively at 3 weeks intervals. Survival data, local control, toxicity of chemotherapy and postoperative complications are presented.

Results

Median follow-up time for metastasis-free survival (MFS) was 2.8 years (range 0.3–10.4). The 5-year MFS was 49.5% (95% confidence interval [CI] 31.7–77.4). The median follow-up time was 5.4 years (range 0.3–10.4) for overall survival (OS). The 5-year OS was 64.0% (95% CI 45.8–89.4). The median tumour size was 13 cm, with undifferentiated pleomorphic sarcoma (n = 10) and synovial sarcoma (n = 6) diagnosed most frequently. All patients completed surgery. Resection margins were R0 in 19 patients and R1 in 1 patient. No patients had evidence of disease progression preoperatively. Three patients experienced a local recurrence, in 2 after lung metastases had already been diagnosed. Eleven patients (55%) had postoperative wound problems (temporary in 8 and persistent in 3).

Conclusions

Preoperative chemotherapy and radiotherapy were associated with temporary wound-healing problems. Survival outcomes, local control and toxicities were deemed satisfactory when considering the locally advanced sarcoma disease status at primary diagnosis.

Trial registration This study was registered at ClinicalTrials.gov Identifier NCT00790244 and with European Union Drug Regulating Authorities Clinical Trials No. EUDRACT 2007-001152-39

Sarcoma treatment in the era of molecular medicine

Sarcomas are heterogeneous and clinically challenging soft tissue and bone cancers. Although constituting only 1% of all human malignancies, sarcomas represent the second most common type of solid tumors in children and adolescents and comprise an important group of secondary malignancies. More than 100 histological subtypes have been characterized to date, and many more are being discovered due to molecular profiling. Owing to their mostly aggressive biological behavior, relative rarity, and occurrence at virtually every anatomical site, many sarcoma subtypes are in particular difficult-to-treat categories. Current multimodal treatment concepts combine surgery, polychemotherapy (with/without local hyperthermia), irradiation, immunotherapy, and/or targeted therapeutics. Recent scientific advancements have enabled a more precise molecular characterization of sarcoma subtypes and revealed novel therapeutic targets and prognostic/predictive biomarkers. This review aims at providing a comprehensive overview of the latest advances in the molecular biology of sarcomas and their effects on clinical oncology; it is meant for a broad readership ranging from novices to experts in the field of sarcoma.

Soft tissue sarcoma: can dynamic contrast-enhanced (DCE) MRI be used to predict the histological grade?

OBJECTIVE

To determine if dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) parameters reflect histological grade of soft tissue sarcoma (STS) MATERIALS AND METHODS: The medical records of 50 patients diagnosed with pathologically confirmed STS were retrospectively reviewed. Each STS was assessed with conventional contrast-enhanced MRI and DCE-MRI using a 3.0-T MRI system. The conventional MRI characteristics of low-grade (grade 1) and high-grade (grade 2 and grade 3) tumors were analyzed. Semi-quantitative parameters, including iAUC and TTP, and quantitative parameters, including K^trans, K_ep, and V_e, were derived from DCE-MRI. The diagnostic performances and optimal thresholds of various combinations of DCE-MRI parameters for predicting histological grades of STS were investigated using receiver operator characteristic (ROC) curves.

RESULTS

On conventional MRI, high-grade STSs were significantly larger (≥ 5 cm) and more likely to show a heterogeneous signal intensity on T₂WI (> 75%), peritumoral hyperintensity on T₂WI, or tumor necrosis (> 50%) compared with low-grade STS. On DCE-MRI, iAUC, TTP, K^trans, and K_ep were significant predictors of STS histological grade. K^trans had a high diagnostic value for differentiating between high-grade and low-grade STSs. The combination of iAUC, TTP, and K^trans yielded a higher AUC value (0.841) than the other models.

CONCLUSION

High-grade STSs were usually larger than low-grade STSs, had unclear boundaries, a heterogeneous signal intensity on T2-weighted image (T₂WI), and extensive necrosis. On DCE-MRI, iAUC, TTP, K^trans, and K_ep could differentiate between high-grade and low-grade STSs. The combination of iAUC, TTP, and K^trans had a high diagnostic performance for differentiating between STS histological grades.

Diagnostic and Clinical Impact of 18F-FDG PET/CT in Staging and Restaging Soft-Tissue Sarcomas of the Extremities and Trunk: Mono-Institutional Retrospective Study of a Sarcoma Referral Center

Background: Soft-tissue sarcomas (STS) represent a wide heterogeneous class of rare tumors. The exact role ¹⁸F-fluorodeoxyglucose positron emission/computed tomography (¹⁸F-FDG PET/CT) in the evaluation of STS is not well established. The aim of the present study was to evaluate how the use of ¹⁸F-FDG PET/CT in STS could influence patient therapy planning, looking for a possible added value over computed tomography and magnetic resonance imaging—the most used modalities in the study of STS. Differences in SUV_max according to histologic subtype and tumor grade were also considered. Methods: a total of 345 consecutive ¹⁸F-FDG PET/CT scans performed for initial staging (n = 171) or for suspected disease relapse (n = 174) in 282 patients with STS extracted from the local Information System database were retrospectively reviewed. Results: ¹⁸F-FDG PET/CT altered therapy planning in 80 cases (16.4% for staging and 29.9% in restaging), both for disease upstaging (58.8%) and downstaging (41.2%) Conclusions: ¹⁸F-FDG PET/CT could significantly influence management of patients with STS, particularly for restaging.

Prognostic Determinants Analysis and Nomogram for Bone Malignant Vascular Tumors: A Surveillance, Epidemiology and End Results (SEER) Analysis

Background

The aim and objective of our investigations were to explore the prognostic value of various clinical and pathological factors of bone malignant vascular tumors and establish a nomogram for their outcome predictions.

Material/Methods

All data of primary bone malignant vascular tumors (MVTs) patients were randomly selected from the Surveillance, Epidemiology and End Results (SEER) database. However, selected patients were clinically diagnosed with various cancers during 1988–2015. The potential prognostic factors were analyzed using SPSS (Windows, version 22.0). All prognostic factors were combined to formulate a nomogram to predict the overall survival (OS).

Results

A total of 266 selected patients were included in our study. In the univariate model, age (P<0.001), sex (p=0.0255), primary site (P<0.001), surgery (P<0.001), histologic type (P<0.001), metastasis (p=0.000), and pathological grade (P<0.001) were statistically significant for patient survival. The results of Cox analysis revealed that age (≥64) HR: 3.636, 95% CI [1.955–6.762], p=0.000, the primary site in skull HR: 2.6, 95% CI [1.584–4.268], p<0.001], without surgery HR: 1.473 95% CI [1.239–1.751], p<0.001, metastasis HR: 3.076 95% CI [1.983–4.771] p=0.000, man HR 1.802, 95% CI [1.032–3.004], p=0.045, and high malignant grade HR: 3.029, 95% CI [2.101–4.366], p=0.003 were independent unfavorable prognostic factors. Angiosarcoma had highest mortality rate among all vascular malignancies. The nomogram predicting overall survival achieved a C-index of 0.694 (95% CI 0.631, 0.745) in the SEER cohort.

Conclusions

Surgery can significantly increase OS survival time for bone MVTs, and low-grade malignancy is a significant factor for OS. However, advanced age, tumor metastasis, primary site in skull, AS, and male sex are predictors of poor prognosis.

Multidisciplinary treatment of soft tissue sarcomas: An update

Standard treatment for soft tissue sarcoma, based on complete surgical resection with or without adjuvant radiotherapy and chemotherapy, has not substantially changed during the last several decades. Nevertheless, recent advances have contributed to considerable improvement in the management of these patients; for example, new magnetic resonance imaging sequences such as diffusion-weighted imaging and magnetic resonance imaging radiomics can better assess tumor extension and even estimate its grade. Detection of circulating genetic material (liquid biopsy) and next-generation sequencing are powerful techniques for genetic analysis, which will increase our understanding of the underlying molecular mechanisms and may reveal potential therapeutic targets. The role of chemotherapy in non-metastatic disease is still controversial, and there is a need to identify patients who really benefit from this treatment. Novel chemotherapeutic regimens have entered clinical praxis and can change the outcome of patients with metastatic disease. Advances in radiotherapy have helped decrease local adverse effects and sustain good local control of the disease. The following report provides an updated view of the diagnosis, treatment, and future perspectives on the management of patients with soft tissue sarcomas.

Radiomics and Machine Learning With Multiparametric Preoperative MRI May Accurately Predict the Histopathological Grades of Soft Tissue Sarcomas

BACKGROUND

Preoperative prediction of the grade of soft tissue sarcomas (STSs) is important because of its effect on treatment planning.

PURPOSE

To assess the value of radiomics features in distinguishing histological grades of STSs.

STUDY TYPE

Retrospective.

POPULATION

In all, 113 patients with pathology-confirmed low-grade (grade I), intermediate-grade (grade II), or high-grade (grade III) soft tissue sarcoma were collected.

FIELD STRENGTH/SEQUENCE

The 3.0T axial T₁ -weighted imaging (T₁ WI) with 550 msec repetition time (TR); 18 msec echo time (TE), 312 × 312 matrix, fat-suppressed fast spin-echo T₂ WI with 4291 msec TR, 85 msec TE, 312 × 312 matrix.

ASSESSMENT

Multiple machine-learning methods were trained to establish classification models for predicting STS grades. Eighty STS patients (18 low-grade [grade I]; 62 high-grade [grades II-III]) were enrolled in the primary set and we tested the model with a validation set with 33 patients (7 low-grade, 26 high-grade).

STATISTICAL TESTS

1) Student's t-tests were applied for continuous variables and the χ² test were applied for categorical variables between low-grade STS and high-grade STS groups. 2) For feature subset selection, either no subset selection or recursive feature elimination was performed. This technology was combined with random forest and support vector machine-learning methods. Finally, to overcome the disparity in the frequencies of the STS grades, each machine-learning model was trained i) without subsampling, ii) with the synthetic minority oversampling technique, and iii) with random oversampling examples, for a total of 12 combinations of machine-learning algorithms that were assessed, trained, and tested in the validation cohort.

RESULTS

The best classification model for the prediction of STS grade was a combination of features selected by recursive feature elimination and random forest classification algorithms with a synthetic minority oversampling technique, which had an area under the curve of 0.9615 (95% confidence interval 0.8944-1.0) in the validation set.

DATA CONCLUSION

Radiomics feature-based machine-learning methods are useful for distinguishing STS grades.

LEVEL OF EVIDENCE

3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2020;51:791-797.

Soft Tissue Sarcomas: Preoperative Predictive Histopathological Grading Based on Radiomics of MRI

RATIONALE AND OBJECTIVES

The purpose of this study is to develop a radiomics model for predicting the histopathological grades of soft tissue sarcomas preoperatively through magnetic resonance imaging (MRI).

MATERIALS AND METHODS

Thirty-five patients who were pathologically diagnosed with soft tissue sarcomas and their histological grades were recruited. All patients had undergone MRI before surgery on a 3.0T MRI scanner. Radiomics features were extracted from fat-suppressed T2-weighted imaging. We used the least absolute shrinkage and selection operator (LASSO) regression method to select features. Then three machine learning classification methods, including random forests, k-nearest neighbor, and support vector machine algorithm were trained using the 5-fold cross validation strategy to separate the soft tissue sarcomas with low- and high-histopathological grades.

RESULTS

The radiomics features were significantly associated with the histopathological grades. Quantitative imaging features (n = 1049) were extracted from fat-suppressed T2-weighted imaging, and five features were selected to construct the radiomics model. The model that used support vector machine classification method achieved the best performance among the three methods, with areas under the receiver operating characteristic curves Area Under Curve (AUC) values of 0.92 ± 0.07, accuracy of 0.88.

CONCLUSION

Good accuracy and AUC could be obtained using only five radiomic features. Therefore, we proposed that three-dimensional imaging features from fat-suppressed T2-weighted imaging could be used as candidate biomarkers for preoperative prediction of histopathological grades of soft tissue sarcomas noninvasively.

The impact of chemotherapy on survival of patients with extremity and trunk wall soft tissue sarcoma: revisiting the results of the EORTC-STBSG 62931 randomised trial

BACKGROUND

This study was aimed at determining whether patients with high-risk soft tissue sarcoma (STS), as identified using the nomogram Sarculator, benefitted from adjuvant chemotherapy in the EORTC-STBSG 62931 randomised controlled trial (RCT), which failed to detect an impact for adjuvant doxorubicin plus ifosfamide (Adj) over observation (Obs).

METHODS

Patients with extremity and trunk wall STS in the EORTC-STBSG 62931 RCT were analysed (N = 290/351). Ten-year predicted probability of overall survival (pr-OS) was calculated using the prognostic nomogram Sarculator. Patients were grouped into three categories of predicted pr-OS: high (pr-OS>66%), intermediate (51<pr-OS≤66) and low (pr-OS≤51%). OS and disease-free survival (DFS) were calculated.

RESULTS

Nomogram pr-OS was dispersed (median 72%, interquartile range 57-83%) and had prognostic value for OS and DFS (log-rank test: P < 0.001). One hundred seventy, 68 and 52 patients had high (58.6%, 90 Obs/80 Adj), intermediate (23.5%, 34 Obs/34 Adj) and low pr-OS (17.9%, 24 Obs/28 Adj), respectively. Adjuvant chemotherapy halved the risk of recurrence (hazard ratio [HR] = 0.46, 95% confidence interval [CI] 0.24-0.89) and death (HR = 0.46, 95% CI 0.23-0.94) in the low pr-OS category, while no effect was detected in intermediate and high pr-OS categories. To strengthen these findings, study participants with pr-OS<60% were combined (N = 80, 27.6%, 39 Obs/41 Adj), and a significant DFS (HR = 0.49, 95% CI 0.28-0.85) and OS (HR = 0.50, 95% CI 0.30-0.90) benefit was detected.

CONCLUSION

Patients of the EORTC-STBSG 62931 RCT with extremity and trunk wall STS and a low predicted pr-OS (high-risk patients) had better outcomes when treated with adjuvant chemotherapy. This may help reconcile the disparate results of clinical studies on adjuvant/neoadjuvant chemotherapy in STS.

Histology driven systemic therapy of liposarcoma-ready for prime time?

Liposarcomas are a subtype of soft tissue sarcomas arising from adipocytes. These mesenchymal tumors have been sub classified into well differentiated liposarcoma (WDLPS), dedifferentiated liposarcoma (DDLPS), myxoid liposarcoma (MLPS) and pleomorphic liposarcoma (PLPS). This article reviews what has been reported regarding the responsiveness of these sarcoma subtypes to traditional and newly developed systemic therapies. The evolution of molecular targets for therapeutic intervention within the distinct histologies is discussed, along with, available evidence regarding the efficacy of novel target directed therapies. Response rates and outcomes for advanced disease therapeutic trials comprises the majority of this information, and where available, data from adjuvant therapy trials is reviewed. Overall survival for patients with advanced liposarcoma treated with systemic therapy is 16.3 months. The article addresses our progress toward the goal of improved liposarcoma outcomes through tailored interventions.

Selection of Patients With Localized Extremity Soft Tissue Sarcoma for Treatment With Perioperative Chemotherapy

OPINION STATEMENT

Soft tissue sarcoma (STS) is a heterogeneous disease, in terms of histologic subtype, body site of presentation, and behavior. Localized soft tissue sarcoma may be cured with complete tumor excision, but overall, outcomes are sub-optimal. Metastatic disease is associated with shortened survival. Systemic therapy has been studied for several decades as adjunctive therapy, but the use of adjuvant and neo-adjuvant chemotherapy remains controversial. The heterogeneity of patients included in clinical trials, and of sarcoma in general, has made it difficult to draw conclusions about which patients with localized STS should be treated with chemotherapy. Over time, published outcomes for STS of the extremities have improved, and one of the factors that contributes to this improvement may be selection of patients most likely to benefit from the prescribed treatment. Recent studies of neo-adjuvant and adjuvant chemotherapy have recruited patients with the highest recurrence risk-those with large, high-grade, deep tumors. It is reasonable, in practice, to apply similar criteria in deciding whether to recommend treatment. Looking ahead, it will be important to refine our ability to identify patients at highest risk of recurrence, and to develop tools to predict which patients and tumors will respond to chemotherapy.