Soft tissue sarcoma

A novel nomogram and prognostic factor for metastatic soft tissue sarcoma survival

Background

This study represented the inaugural effort to develop predictive survival nomograms for metastatic soft tissue sarcoma (mSTS) patients in the era of immune checkpoint inhibitors.

Method

From the Surveillance, Epidemiology, and End Results (SEER) program database, we extracted 3078 eligible patients with mSTS between 2016 and 2022. Kaplan-Meier survival analysis, univariate and multivariable Cox analyses, and univariate and multivariable logistic analyses were conducted. Subsequently, predictive nomograms were constructed. Clinical effectiveness was validated using the area under the curve (AUC), calibration curve, and decision curve analysis (DCA) methods.

Results

We used the SEER database to include 3078 eligible patients with mSTS between 2016 and 2022. All the eligible patients were randomly allocated in a ratio of 6:4 and stratified into a training group (n = 1846) and a validation group (n = 1232). In the multivariate Cox analysis, age, race, marital status, pathological grade, histologic subtype, surgery, and chemotherapy were identified as independent prognostic factors. These factors were used to construct the nomogram to predict the 1-, 3-, and 5-year OS of mSTS patients. The C-index for the training cohort and the validation cohort was 0.722(95% confidence interval [CI]: 0.708-0.736), and 0.716(95% CI: 0.698-0.734), respectively. The calibration curves for 1-, 3-, and 5-year OS probability demonstrated excellent calibration between the predicted and the actual survival. The AUC values of the nomogram at 1-, 3-, and 5-year were 0.785, 0.767, and 0.757 in the training cohort, 0.773, 0.754, and 0.751 in the validation cohort, respectively. Furthermore, DCA indicated the favorable clinical utility of the nomogram in both cohorts. The risk stratification system was constructed using the established nomogram, which enhanced prediction accuracy, aided clinicians in identifying high-risk patients and informing treatment decisions.

Conclusion

This study marked the inaugural effort in constructing predictive survival nomograms mSTS patients in the era of immune checkpoint inhibitors. The robustly constructed nomograms, alongside actual outcomes, offered valuable insights to inform follow-up management strategies.

Radiotherapy, volume reduction, and short-term surgical outcomes in the treatment of large myxoid liposarcomas

Purpose

While tumor volume reduction following radiation has been documented in myxoid liposarcomas, it is unclear whether large tumors experience similar volume reduction to smaller tumors.

Materials and Methods

MRI studies performed before and after completion of pre-operative radiation therapy (RT) were examined. Tumor sizes were noted and categorized as large versus small based on size >10 cm. Tumor volumes were calculated, and operative duration and major wound complications were recorded.

Results

The median largest tumor dimension was 12.4 cm before RT and 8.7 cm after RT. The median tumor volume was 298.9 cm3 before RT and 106.9 cm3 after RT. There was no significant difference in the mean percent tumor volume reduction between large tumors and small tumors (p = 0.11, 56.3% vs. 64.5%). Operative duration most strongly correlated to post-RT MRI volume (R2=0.674, p<0.001). Despite volume reduction, tumors that were large on presentation were more likely to experience major wound complications post-operatively.

Conclusion

Radiation appears to be as effective at reducing myxoid liposarcoma tumor volume in large and small tumors. However, large tumors on presentation appear more likely to experience wound complications despite tumor volume reduction. Future studies should investigate disease-related outcomes as a factor of volume reduction in myxoid liposarcoma.

Comparing Apparent Diffusion Coefficient and FNCLCC Grading to Improve Pretreatment Grading of Soft Tissue Sarcoma-A Translational Feasibility Study on Fusion Imaging

Simple Summary

Histological subtype and grading are essential for the planning of soft tissue sarcoma. Pretherapeutic grading based on core needle biopsies is frequently not reliable due to intratumoral heterogeneity. This pilot study assessed the ability of functional radiological imaging to improve histopathological grading. Multiple biopsies were taken from the sarcoma specimens during tumor resection and radiopaque markers were placed. Subsequently, fusion of preoperative magnetic resonance imaging and postoperative computed tomography of the specimen allowed for comparison of histopathological grading and diffusion-weighted imaging. The apparent diffusion coefficient appears to correlate with FNCLCC criteria and may supplement pretreatment assessment and multimodal treatment allocation in soft tissue sarcoma.

Abstract

Histological subtype and grading are cornerstones of treatment decisions in soft tissue sarcoma (STS). Due to intratumoral heterogeneity, pretreatment grading assessment is frequently unreliable and may be improved through functional imaging. In this pilot study, 12 patients with histologically confirmed STS were included. Preoperative functional magnetic resonance imaging was fused with a computed tomography scan of the resected specimen after collecting core needle biopsies and placing radiopaque markers at distinct tumor sites. The Fédération Nationale des Centres de Lutte Contre le Cancer (FNCLCC) grading criteria of the biopsies and apparent diffusion coefficients (ADCs) of the biopsy sites were correlated. Concordance in grading between the specimen and at least one biopsy was achieved in 9 of 11 cases (81.8%). In 7 of 12 cases, fusion imaging was feasible without relevant contour deviation. Functional analysis revealed a tendency for high-grade regions (Grade 2/3 (G2/G3)) (median (range) ± standard deviation: 1.13 (0.78–1.70) ± 0.23 × 10⁻³ mm²/s) to have lower ADC values than low-grade regions (G1; 1.43 (0.64–2.03) ± 0.46 × 10⁻³ mm²/s). In addition, FNCLCC scoring of multiple tumor biopsies proved intratumoral heterogeneity as expected. The ADC appears to correlate with the FNCLCC grading criteria. Further studies are needed to determine whether functional imaging may supplement histopathological grading.

Soft Tissue Sarcomas: A 16-Year Experience of a Tertiary Referral Hospital in North Jordan

Background and Objectives: Sarcomas are rare malignant tumors of mesenchymal origin. Their low prevalence and histological heterogeneity make their diagnosis a challenging task. To the best of our knowledge, the epidemiology of soft tissue sarcomas (STSs) was not well studied in Jordan. This study thus aimed to determine STS epidemiologic trends at King Abdullah University Hospital (KAUH); a tertiary hospital that provides cancer healthcare for 70% of the population in Irbid Governorate, North Jordan. The findings of this study will provide a good reference point of the burden of STSs in Jordan and the Middle East region. Materials and Methods: All cases with confirmed STS diagnoses who attended KAUH from January 2003 until December 2018 were included in the initial analysis. Bone sarcomas, gastrointestinal stromal tumors and uterine sarcomas were not included in the study. Information collected from the pathology reports and electronic medical records was used to determine STS prevalence, incidence rate, age and gender distributions, histological types and anatomic location. Cases were reviewed by three pathologists with interest in soft tissue tumors. The findings were compared with literature. Results: In total, 157 STS cases were reported (1.9% of cancers diagnosed at KAUH during the 16-year study period). Crude annual incidence rate (IR) per 100,000 person-years ranged from 0.48 in 2015 to 1.83 in 2011 (average = 1.04). Age-standardized IR (ASR)(World WHO 2000-2025) was 1.37. Male:female ratio was 1.3:1. Median age was 39 years. Age ranged from <1 year to 90 years. Overall STS rates increased with age. The most common histological types were liposarcoma (19%), rhabdomyosarcoma (17%) and leiomyosarcoma (10%). The most common anatomic location was the extremity (40.1%), followed by the trunk (14.7%), then head and neck (10.8%). Conclusion: STSs are rare in North Jordan. A slight increase in their incidence was identified during the study period similar to global trends. The collection of relevant data on established risk factors along with a broader scale evaluation of the epidemiology of STS in the Middle East region is recommended to better evaluate disease burden and trends.

Molecular Alterations in Pediatric Fibroblastic/Myofibroblastic Tumors: An Appraisal of a Next Generation Sequencing Assay in a Retrospective Single Centre Study

BACKGROUND

Pediatric fibroblastic/myofibroblastic tumors (PFMTs) can be challenging to definitively classify. Large case series or diagnostic updates have not been recently published despite identification of molecular alterations that could improve diagnostic accuracy. Our review of the literature found that over two-thirds of the more than 30 types of PFMTs harbor recurrent molecular alterations. We performed an institutional review of PFMTs to highlight limitations of a predominantly morphological classification, and evaluated the utility of a next-generation sequencing assay to aid diagnosis.

METHODS

PFMTs identified over a period of 12 years were reviewed, categorized per the new WHO classification, and tested using the Oncomine Childhood Cancer Research Assay.

RESULTS

Eighty-seven specimens from 58 patients were reviewed; 50 were chosen for molecular analysis, 16 (32%) lacking definitive classification. We identified alterations, some novel, in 33% of assayed cases. Expected alterations were identified for most known diagnoses and mutations were identified in 6 of 16 tumors (38%) that were initially unclassified.

CONCLUSION

We confirmed a significant subset of PFMTs remain difficult to classify using current criteria, and that a combined DNA/RNA assay can identify alterations in many of these cases, improving diagnostic certainty and suggesting a clinical utility for challenging cases.

Prognostic factors and impact of surgery in patients with metastatic soft tissue sarcoma at diagnosis: A population-based cohort study

BACKGROUND

Approximately 10% of the patients with soft tissue sarcoma show metastasis at initial diagnosis, and hence, poorer prognosis. However, the prognostic factors and whether definitive surgery for the primary lesion improves overall survival, especially when complete resection of metastasis is difficult, remain unclear.

METHODS

This retrospective analysis was based on the Bone and Soft Tissue Tumor Registry in Japan. Patients with soft tissue sarcoma having metastasis at diagnosis were enrolled, excluding those with Ewing's sarcoma, rhabdomyosarcoma and several other sarcomas with unique behavior and treatment strategies. Overall survival was estimated using the Kaplan-Meier method and compared among the common histologic subtypes. Multivariate analysis with the Cox regression model was used to identify the prognostic factors.

RESULTS

In total, 1184 patients were included, with a median follow-up duration of 10 months (range: 1-83). The median overall survival was 21 months (95% confidence interval: 18.2-23.8). The multivariate analyses indicated that tumor size, grade and histologic subtypes significantly correlated with overall survival. Moreover, surgery for the primary lesion, in addition to surgery for metastases and chemotherapy, showed significant association with better survival.

CONCLUSIONS

The prognostic factors in patients with metastatic soft tissue sarcoma at diagnosis are generally similar to those in patients with localized disease. The overall survival in patients differed significantly according to histologic subtype. Surgical resection of primary lesions, especially those with a wide margin, may be an independent prognostic factor. Further studies are needed identify which subgroup of patients would benefit the most from primary lesion surgery.

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.

Impact of NICE guidelines on the survival of patients with soft-tissue sarcomas

AIMS

Urgent referral to a specialist centre for patients with a soft-tissue sarcoma (STS) has been recommended by the National Institute for Health and Care Excellence (NICE) in the UK since 2006. However, the impact of this recommendation on the prognosis for these patients remains unclear. We aimed to determine the impact of the NICE guidelines on the disease-specific survival (DSS) of patients with an STS.

METHODS

A total of 2,427 patients with an STS referred to a supraregional centre in the ten-year periods before (n = 1,386) and after (n = 1,041) the issue of the NICE guidelines were evaluated.

RESULTS

The mean size of the tumour was significantly smaller at the time of diagnosis (10.3 cm (SD 6.5) vs 9.1 cm (SD 6.2); p < 0.001) and the number of patients who had undergone an inadvertent excision significantly decreased (28% (n = 389) vs 20% (n = 204); p < 0.001) following the introduction of the NICE guidelines. The five-year DSS was 63% in the pre-NICE and 71% in post-NICE groups (p < 0.001). The improved survival was more significant for those with a high-grade tumour (pre-NICE, 48%; post-NICE, 68%; p < 0.001). In those with a high-grade tumour, the mean size of the tumour (11.6 cm (SD 6.2) vs 9.6 cm (SD 5.8); p < 0.001) and the number of patients with metastasis at the time of diagnosis (15% (n = 124 vs 10% (n = 80); p = 0.007) significantly decreased in the post-NICE group.

CONCLUSION

An improvement in survival was seen after the introduction of the NICE guidelines, especially in patients with a high-grade STS. More patients were referred at an earlier stage, indicating a clearer pathway after the issue of national policy for the management of STSs in the UK. Cite this article: Bone Joint J 2021;103-B(3):569-577.

Extremity Soft Tissue Sarcoma: Role of Local Control

OPINION STATEMENT

For localized extremity soft tissue sarcoma (eSTS), treatment is individualized and each patient needs to be evaluated by a multidisciplinary team at a referral sarcoma center specialized in the care of sarcoma. For a majority of patients, treatment for eSTS involves limb-salvage surgery, with or without the addition of radiation therapy. Surgery should only be performed by surgeons specifically fellowship trained in the resection of eSTS. Surgery alone may be considered for small, low-grade, and superficial tumors as long a wide (≥ 2 cm) margin can be achieved. In cases where a less than wide negative margin can be achieved, radiation therapy should be utilized to facilitate a planned close margin resection to preserve critical structures (such as nerves, blood vessels, and bone) without a significant impact on oncologic outcomes. Soft tissue sarcomas are rare, and as such patients often present following an inadvertent excision. In these situations, we recommend preoperative radiation and wide tumor bed re-excision, as rates of residual tumor can be high in this scenario. While there is large amount of evidence to support the use of radiotherapy to enhance local tumor control, the evidence to support the use of chemotherapy to enhance local tumor control is lacking, and as such cannot be recommended for all patients.

Clinical and biological implications of Hippo pathway dysregulation in sarcomas

Sarcomas are mesenchymal malignant tumors with poor prognosis and limited treatment options. Hippo pathway is a recently discovered pathway normally involved in organ development and wound healing. Hippo signaling is often altered in solid tumors. The molecular elements of Hippo signaling include MST1/2 and LATS1/2 kinases which phosphorylate and regulate the activity of YAP and TAZ co-transcriptional activators. Hippo pathway cross-talks with several molecular pathways with known oncogenic function. In sarcomas Hippo signaling plays a pivotal role in tumorigenesis, evolution and resistance in chemotherapy regimens. Targeting Hippo pathway could potentially improve prognosis and outcome of sarcoma patients.

Magnetic resonance guided focused ultrasound for treatment of bone tumors

AIMS

Magnetic resonance guided focused ultrasound (MRgFUS) is a new modality in the management of primary and secondary bone tumors. We aimed to investigate the safety, efficacy, and feasibility of using MRgFUS for the treatment of (1) benign bone tumors with the intent of complete tumor ablation, (2) primary malignant bone tumors with the intent to assess its effectiveness in causing tumor necrosis, and (3) metastatic bone disease with the intent of pain relief.

METHOD

Twenty-four patients with benign bone tumors, primary malignant bone tumors, and metastatic bone disease were treated with one session of MRgFUS. Contrast-enhanced (CE) magnetic resonance imaging (MRI) was carried out post-procedure to assess and quantify the area of ablation. Those with malignant primary tumors had the tumors resected 2 weeks after the treatment and the ablated areas were examined histopathologically (HPE). The other patients were followed up for 3 months to assess for the side effects and pain scores.

RESULTS

Significant volume of ablation was noted on CE MRI after the treatment. Benign bone tumors were ablated with minimal adverse effects. Metastatic bone disease was successfully treated with significant decrease in pain scores. Ablated primary malignant tumors showed significant coagulative necrosis on MRI and the HPE showed 100% necrosis. Pain scores significantly decreased 3 months after the procedure. Only two patients had superficial skin blistering and three patients had increase in pain scores immediately after treatment.

CONCLUSION

MRgFUS is effective, safe, and noninvasive procedure that can be an adjunct in the management of primary and metastatic bone tumors.

Patterns of care of superficial soft tissue sarcomas: it is not always just a lump

AIM

Superficial soft tissue sarcomas (S-STS) are generally considered low-risk tumors and have an excellent prognosis when treated with appropriate surgery and adjuvant therapy. However, they are often misdiagnosed then mistreated, leading to significant morbidity. This study aims to examine the patterns of care and outcomes of patients with S-STS, comparing those initially managed through sarcoma units versus elsewhere.

METHODS

Patients with S-STS from Prince of Wales Hospital in NSW (1995-2013) and Peter MacCallum Cancer Centre in Victoria (2009-2013) were identified from a national sarcoma database. Baseline variables, treatment and disease outcomes were recorded. Statistical tests performed included univariate and multivariate analyses, chi-square tests, as well as the Kaplan-Meier method for 5-year local recurrence and survival rates.

RESULTS

Eighty-nine patients were identified, with 35% initially managed at a sarcoma unit and 65% elsewhere. Patients initially managed at sarcoma units had larger tumors (>5 cm 39% vs 17%; P  =  0.036) with a trend to higher grade (61% vs 48%; P = 0.39). Patients that were initially managed outside a sarcoma unit more often underwent open surgical biopsies (P < 0.0005), had multiple operations (P < 0.0005) and had higher rates of local recurrences (24% vs 6.5%, P  =  0.038). They also had lower 5-year local recurrence-free survival rates (P = 0.022), but had higher metastasis-free survival (P = 0.014). On multivariate analysis, only larger STS size and male gender predicted for poorer metastasis-free survival (P = 0.042 and 0.018, respectively).

CONCLUSION

Patients with S-STS initially managed outside specialized sarcoma units undergo more operations, with risk of greater morbidity, and have greater risk of local recurrence.

The diagnosis and treatment of soft tissue sarcomas of the limbs

BACKGROUND

The diagnosis of soft-tissue sarcomas of the limbs is often delayed, sometimes markedly so, even though prompt and appropriate treatment improves survival and lowers the amputation rate.

METHODS

On the basis of a selective literature review and consideration of the relevant guidelines, we developed an algorithm that can serve as a guide to the diagnosis of soft-tissue tumors in general and to the treatment of soft-tissue sarcomas of the limbs.

RESULTS

Surgical resection accompanied by multimodal therapy is the only treatment strategy for soft-tissue sarcoma that provides a chance of cure. Particularly when the tumor is located in the distal part of a limb, plastic-reconstructive surgical techniques often enable adequate local control, along with limb salvage and preservation of function. The role of adjuvant or neo-adjuvant radiotherapy and/or chemotherapy is currently debated. The overall survival rate at 5 years is 87% for low-grade sarcomas and 62% for high-grade sarcomas.

CONCLUSION

Any solid mass of the limbs that has been present for more than four weeks requires diagnostic evaluation. Excisional biopsy is suitable only for epifascial lesions measuring less than 5 cm in diameter. All other lesions should be imaged with MRI and then diagnosed with an incisional biopsy. Patients with soft tissue sarcomas must be treated in an interdisciplinary collaboration so that they can undergo multimodal treatment. The proposed algorithm should help avoid delays in diagnosis and optimize treatment strategies.

Tratamento radioterápico adjuvante nos sarcomas de extremidades de alto grau

OBJETIVO: Avaliar as terapias utilizadas em nossa instituição no tratamento dos sarcomas de extremidades de alto grau, mediante análise da sobrevida global do tratamento multidisciplinar. MATERIAIS E MÉTODOS: Estudo retrospectivo com 36 pacientes, no período de 1993 a 2007, em estádios IIb/III, submetidos a radioterapia externa após cirurgia com ou sem reforço de dose com braquiterapia. RESULTADOS: Trinta e seis pacientes foram submetidos a tratamento cirúrgico seguido de radioterapia externa, sendo que quatro pacientes (11%) receberam reforço de dose com braquiterapia e sete pacientes (19%) receberam quimioterapia. A dose mediana de radioterapia foi de 50 Gy (IC95%: 47-53 Gy), sendo realizado reforço de dose em quatro pacientes com braquiterapia, com dose variando de 16,2-35 Gy. A quimioterapia foi indicada em sete pacientes (19%) com margens positivas. Quinze pacientes apresentaram recidiva local e/ou a distância (42%) e todos faleceram. Vinte e um pacientes (58%) encontram-se sem evidência clínica e radiológica de recidiva local e/ou a distância. O seguimento mediano é de 88 meses (IC95%: 74-102). A taxa de sobrevida global para sete anos foi de 80%. CONCLUSÃO: Concluímos que a associação cirurgia + radioterapia apresenta-se como tratamento eficaz e com ótimas respostas e melhora da sobrevida global na possibilidade de associação da braquiterapia.

[Diagnosis and treatment of soft-tissue tumors]

The diagnostic and therapeutic management of patients with soft-tissue tumors would be similar to the approach used for bone tumors if it were not for one crucial factor: the absolute necessity to recognize a sarcoma. The predominant features are the size of the tumor and its superficial or deep localization. If the tumor is small and superficial, biopsy can be associated with immediate resection without risk of dissemination to the deep tissues: this is the biopsy-resection approach. If the tumor is deep or superficial but large sized, search for locoregional spread with MRI is necessary before undertaking any surgical procedure. MRI can help guide the biopsy and plan resection if the tumor is a sarcoma. A first biopsy is necessary to establish the histological diagnosis and elaborate the therapeutic strategy. Samples should be sent immediately to the pathology lab which should examine sterile fresh tissue. Experience has demonstrated that proper rules for diagnosis and treatment are not necessarily applied initially in approximately one-fourth of all subjects with a malignant soft-tissue tumor. Besides the medical problems caused by this situation, the patient loses a chance for cure. When the tumor is a sarcoma, surgery is the basis of treatment. Complementary radiation therapy may be necessary, particularly for high-grade tumors or if the surgical margin was insufficient. Systemic or locoregional chemotherapy can also be used for high-grade or non-resectable tumors.

Diagnostik von Tumoren des Stütz- und Bewegungsapparates

Malignant bone and soft tissue tumors are rare diseases. In case of a suspected tumor one should strictly apply the algorithm proposed, in order to avoid misdiagnoses and mistreatment. Optimal therapy can only be achieved by close cooperation between the departments involved--oncology, orthopaedic surgery, pathology, plastic surgery, radiology and radiooncology.

From the archives of the AFIP: Imaging of synovial sarcoma with radiologic-pathologic correlation

Synovial sarcoma is the fourth most common type of soft-tissue sarcoma, accounting for 2.5%-10.5% of all primary soft-tissue malignancies worldwide. Synovial sarcoma most often affects the extremities (80%-95% of cases), particularly the knee in the popliteal fossa, of adolescents and young adults (15-40 years of age). Despite its name, the lesion does not commonly arise in an intraarticular location but usually occurs near joints. Histologic subtypes include monophasic, biphasic, and poorly differentiated; the cytogenetic aberration of the t(X;18) translocation is highly specific for synovial sarcoma. Although radiographic features of these tumors are not pathognomonic, findings of a soft-tissue mass, particularly if calcified (30%), near but not in a joint of a young patient, are very suggestive of the diagnosis. Cross-sectional imaging features are vital for staging tumor extent and planning surgical resection; they also frequently reveal suggestive appearances of multilobulation and marked heterogeneity (creating the "triple sign") with hemorrhage, fluid levels, and septa (creating the "bowl of grapes" sign). Two features associated with synovial sarcoma that may lead to an initial mistaken diagnosis of a benign indolent process are slow growth (average time to diagnosis, 2-4 years) and small size (< 5 cm at initial presentation); in addition, these lesions may demonstrate well-defined margins and homogeneous appearance on cross-sectional images. Synovial sarcoma is an intermediate- to high-grade lesion, and, despite initial aggressive wide surgical resection, local recurrence and metastatic disease are common and prognosis is guarded. Understanding and recognizing the spectrum of appearances of synovial sarcoma, which reflect the underlying pathologic characteristics, improve radiologic assessment and are important for optimal patient management.

Prognostic impact of immunohistochemical expression of ezrin in highly malignant soft tissue sarcomas

PURPOSE

Ezrin is a cytoskeleton linker protein that is actively involved in regulating the growth and metastatic capacity of cancer cells. It has recently been reported to be involved in dissemination of pediatric soft tissue sarcoma (STS).

EXPERIMENTAL DESIGN

To further evaluate the prognostic value of ezrin in STS progression, we screened 50 primary STSs of high malignancy grade using immunohistochemistry. At the initial surgery, all patients were without local or distant metastasis. The expression was then compared with the outcome during follow-up for at least 4 years or until the patients' death.

RESULTS

Twenty-five of the 50 STSs analyzed (50%) showed ezrin immunoreactivity in the membrane and cytoplasm of the tumor cells. A significant association was shown between positive expressions of ezrin and death in disease as well as overall survival (P = 0.014 and 0.007, respectively). Similarly, ezrin expression was significantly associated with development of distant metastasis during follow-up (P = 0.031), also excluding locally recurrent disease (P = 0.049). The relative abundance of metastasis in ezrin-positive cases was observed both over time and irrespective of time. In comparison with clinical, histopathologic, and genetic characteristics of the STSs, ezrin expression was found to correlate significantly with an infiltrative growth pattern outside the tumor capsule as well as with copy number gain of chromosomal region 9cen-q22.

CONCLUSION

Our findings suggest that ezrin immunoreactivity could be valuable as an additional prognostic marker in highly malignant STSs and support a causative role of ezrin in STS tumor dissemination.

A Robust Assay for Alternative Lengthening of Telomeres in Tumors Shows the Significance of Alternative Lengthening of Telomeres in Sarcomas and Astrocytomas

Purpose and Experimental Design: Telomeres of tumor cells may be maintained by telomerase or by alternative lengthening of telomeres (ALT). The standard ALT assay requires Southern analysis of high molecular weight genomic DNA. We aimed to establish and validate an ALT assay suitable for archived paraffin-embedded tumors and to use it to examine the prevalence and clinical significance of ALT in various types of tumors that are often telomerase negative.

Results: To assay for ALT, we detected ALT-associated promyelocytic leukemia (PML) bodies (APBs) by combined PML immunofluorescence and telomere fluorescence in situ hybridization. APBs are PML nuclear domains containing telomeric DNA and are a known hallmark of ALT in cell lines. The APB assay concurred with the standard ALT assay in 62 of 62 tumors and showed that 35% of 101 soft tissue sarcomas (STS), 47% of 58 osteosarcomas (especially younger patients), 34% of 50 astrocytomas, and 0% of 17 papillary thyroid carcinomas were ALT positive (ALT+). The prevalence of ALT varied greatly among different STS subtypes: malignant fibrous histiocytomas, 77%; leiomyosarcomas, 62%; liposarcomas, 33%; synovial sarcomas, 9%; and rhabdomyosarcomas, 6%. ALT correlated with survival in glioblastoma multiforme and occurred more often in lower-grade astrocytomas, but ALT+ and ALT− sarcomas were equally aggressive in terms of grade and clinical outcome.

Conclusion: The APB assay for ALT is suitable for paraffin-embedded tumors. It showed that a substantial proportion of STS, osteosarcomas, and astrocytomas, but not papillary thyroid carcinomas use ALT. APB positivity correlated strongly with survival of patients with astrocytomas.

Insulin-Like Growth Factor Type 1 Receptor Expression Correlates to Good Prognosis in Highly Malignant Soft Tissue Sarcoma

Purpose: To evaluate known and suggested prognostic markers, especially insulin-like growth factor type 1 receptor (IGF-1R), in highly malignant soft tissue sarcomas (STS).

Experimental Design: A cohort of 101 patients with primary STS of high malignancy grade was studied with respect to development of metastasis, local recurrence, and survival during a minimum of 5 years follow-up. All tumors were analyzed by immunohistochemistry for expression of Ki-67, p53, p27, Bcl-2, IGF-1R, and microvessel density. The traditional clinical variables size, malignancy grade (3 or 4), necrosis, mitotic frequency, infiltrative tumor growth, vascular invasion, depth, and surgical margins were also evaluated.

Results: A significant association was shown between high expression of IGF-1R and favorable outcome. Among STS with positive IGF-1R immunoreactivity, cases with high expression (76-100% positive cells) had the best outcome, whereas cases with the lowest expression (1-25% positive cells) had the worst. As expected, large tumor size (&gt;11 cm), presence of necrosis, high mitotic count, intralesional surgery, and deep location were all significantly associated with poor outcome, both in univariate and multivariate analyses. No difference in outcome was observed between cases of malignancy grade 3 versus 4, whereas the included and more objective variables necrosis and mitotic count were found to be reliable prognostic markers.

Conclusion: IGF-1R expression is a common feature of highly malignant STS. Further elucidation of the role of IGF-1R and the IGF system in STS may both provide a basis for development of new prognostic tools in STS, as well as shed light on the basic mechanisms of the STS development.

Status of Surgical Margins and Prognosis in Adult Soft Tissue Sarcomas of the Extremities: A Series of Patients Treated at a Single Institution

Purpose

To explore the prognostic effect of microscopic marginal status after surgery for extremity soft tissue sarcomas.

Patients and Methods

We analyzed 911 consecutive patients surgically treated throughout a 20-year span at a single referral center. Six hundred forty-two were first seen with a primary tumor, and 269, with a locally recurrent tumor. All patients underwent macroscopically complete resection. Microscopic marginal status was negative (tumor size > 1 mm) in 748 patients and positive (≤ 1 mm) in 163 patients. Median follow-up was 107 months.

Results

Patients with primary disease had a lower disease-specific mortality in comparison to those first examined for recurrence (25% v 37%, respectively, at 10 years). Size, malignancy grade, depth, histotype, and local recurrence had a statistically significant prognostic effect at multivariable analysis, while microscopically positive surgical margins had not, though a trend in favor of negative margins was observed. However, an extra risk was observed for patients with positive margins after 3 to 5 years (hazard ratio, 1.8 after 5 years v 0.8 before 5 years). In patients treated for a local recurrence, the prognostic impact of positive margins was higher (hazard ratio, 1.6).

Conclusion

Positive surgical margins had a weak adverse prognostic effect, which was more pronounced for those patients escaping an early relapse. This would seem to justify a policy of surgical adequacy in adult soft tissue sarcomas, though clinical decision making in borderline presentations for conservative surgery might be reasonably flexible and shared with the patient. Once a local relapse has occurred, the impact of local treatments seems more critical.

Detection and Grading of Soft Tissue Sarcomas of the Extremities with18F-3′-Fluoro-3′-Deoxy-l-Thymidine

PURPOSE

The aim of the study was to investigate the feasibility of (18)F-3'-fluoro-3'-deoxy-L-thymidine positron emission tomography (FLT-PET) for the detection and grading of soft tissue sarcoma (STS).

EXPERIMENTAL DESIGN

Nineteen patients with 20 STSs of the extremities were scanned, using attenuation corrected whole-body FLT-PET. Standardized uptake values (SUVs) and tumor:nontumor ratios (TNTs) were compared with histopathological parameters using French and Japanese grading systems.

RESULTS

Mean SUV, maximal SUV, and TNT could differentiate between low-grade (grade 1; n = 6) STS and high-grade (grade 2 and 3; n = 14) STS according to the French grading system (P = 0.001). Mean SUV, max SUV, and TNT correlated with mitotic score, MIB-1 score, the French and Japanese grading system (* = 0.550-0.747).

CONCLUSIONS

FLT-PET is able to visualize STS and differentiate between low-grade and high-grade STS. The uptake of FLT correlates with the proliferation of STS.

Clinicopathologic re-evaluation of 100 malignant fibrous histiocytomas: prognostic relevance of subclassification

PURPOSE

Malignant fibrous histiocytoma (MFH) has been regarded as the most common soft tissue sarcoma (STS) in adults. Yet its true nature and the validity of this diagnostic concept have increasingly been questioned. Available data suggest that most patients with MFH can be subclassified into specific STS types, but the clinical relevance of such categorization has been argued. In a retrospective study, we reclassified 100 tumors of the extremity and trunk wall primarily diagnosed as MFH and analyzed the outcome.

PATIENTS AND METHODS

Patients were adults (median age, 70 years; range, 32 to 94 years). The median tumor size was 8 cm (range, 1 to 30 cm), and the thigh was the most common tumor location (n = 31). Median follow-up was 8 years (range, 3 to 16 years). The overall 5-year metastasis-free survival rate was 0.64. The tumors were reanalyzed histologically, immunohistochemically, and, where available, ultrastructurally, and were classified according to strict diagnostic criteria. Patients were staged according to the American Joint Committee on Cancer system, and prognoses were compared among different groups of the reclassified diagnoses, paying special attention to myogenic tumors.

RESULTS

In 84 of 100 tumors, a specific line of differentiation was either proved or strongly suggested. The most common diagnoses were myxofibrosarcoma (n = 22) and leiomyosarcoma (n = 20). Overall, 30 tumors could be grouped as some form of myogenic sarcoma. These tumors had a worse prognosis, even within the same American Joint Committee on Cancer stage, and a shorter time to metastasis than nonmyogenic tumors.

CONCLUSION

This retrospective study confirms that most so-called MFH can be subclassified by defined criteria; it provides evidence that such classification is clinically important. Specifically, pleomorphic STS showing myogenic differentiation are significantly more aggressive, a finding that allows planning future therapeutic trials.

Prognostic factors for the outcome of chemotherapy in advanced soft tissue sarcoma: an analysis of 2,185 patients treated with anthracycline-containing first-line regimens--a European Organization for Research and Treatment of Cancer Soft Tissue and Bone Sarcoma Group Study

PURPOSE

A total of 2,185 patients with advanced soft tissue sarcomas who had been treated in seven clinical trials investigating the use of doxorubicin- or epirubicin-containing regimens as first-line chemotherapy were studied in this prognostic-factor analysis.

PATIENTS AND METHODS

Overall survival time (median, 51 weeks) and response to chemotherapy (26% complete response or partial response) were the two end points. The cofactors were sex; age; performance status; prior therapies; the presence of locoregional or recurrent disease; lung, liver, and bone metastases at the time of entry onto the trial; long time period between the initial diagnosis of sarcoma and entry onto the study; and histologic type and grade.

RESULTS

Univariate analyses showed (a) a significant, favorable influence of good performance status, young age, and absence of liver metastases on both survival time and response rate, (b) a significant, favorable influence of low histopathologic disease grade on survival time, despite a significantly lower response rate, (c) increased survival time for patients with a long time period between the initial diagnosis of sarcoma and entry onto the study, despite equivalent response rates, and (d) increased survival time with liposarcoma or synovial sarcoma, a decreased survival time with malignant fibrous histiocytoma, a lower response rate with leiomyosarcoma, and a higher response rate with liposarcoma (P < .05 for all log-rank and chi2 tests). The Cox model selected good performance status (P < .0001), absence of liver metastases (P = .0001), low histopathologic grade (P = .0002), long time lapse since initial diagnosis (P = .0004), and young age (P = .0045) as favorable prognostic factors of survival time. The logistic model selected absence of liver metastases (P < .0001), young age (P = .0024), high histopathologic grade (P = .0051), and liposarcoma (P = .0065) as favorable prognostic factors of response rate.

CONCLUSION

This analysis demonstrates that for advanced soft tissue sarcoma, response to chemotherapy is not predicted by the same factors as is overall survival time. This needs to be taken into account in the interpretation of trials assessing the value of new agents for this disease on the basis of response to treatment.

Prognostic factors in soft tissue sarcoma

Several prognostic markers have been identified for soft tissue sarcomas. However, there reproducibility as regards both classification by different examiners and prognostic strength, as evaluated in different tumor series is poorly documented. Relevant factors and their strength differ in different subtypes of sarcoma. Thus, there is no generally accepted prognostic/staging system for soft tissue sarcoma. It seems possible that highly malignant soft tissue sarcomas behave like highly malignant bone tumors, such as osteosarcoma and Ewing sarcoma-i.e., almost all patients have metatastic disease when the primary tumor is diagnosed, although in most cases it is not detectable with today's imaging techniques. The highly malignant character of these tumors is defined by their histotype alone and the microscopic diagnosis is almost always easy. In contrast, no soft tissue sarcoma histotype is per se associated with such a poor prognosis: further prognostic markers are needed. The ideal prognostication system includes only two groups of patients; after removal of the primary tumor, one group has 100% survival and the other 0% survival. In the latter group, the tumor has metastasized and adjuvant therapy is necessary to improve survival. Meaningful chemotherapy trials requires reliable identification of high-risk patients; only these should be included. Inclusion of also low-risk patients is disadvantageous for two reasons: chemotherapy may have serious side-effects and positive effects may be difficult to detect when the trial is diluted by low-risk patients. Prognostication in soft tissue sarcoma has improved, but it may a long time before soft tissue sarcoma histotypes as highly malignant as osteosarcoma and Ewing sarcoma can be defined. Another approach would be to ignore efforts to characterize prognostic features of the primary tumor and instead, with some type of tracer technique (see pp x-y in this issue), focus on whether it has metastasized or not.

Prognostic value of Ki-67 expression in 182 soft tissue sarcomas. Proliferation--a marker of metastasis?

Soft tissue sarcomas (STS) are characterized by deregulated proliferation. Ki-67 is a cell cycle antigen which may be elevated in proliferative states. We analysed Ki-67 expression in fixed and embedded tissues from STS in order to examine associations between proliferation, primary tumour characteristics, and metastasis. One hundred and eighty-two adult patients with trunk wall or extremity STS were treated at our institution between 1980 and 1992 (35 developed local recurrence and 56 developed metastases). Median follow-up time for survivors was 6 years (1-13). We used a semiquantitative score to the assess percentage of Ki-67-positive cells: < or = 10% (n = 86), > 10-25% (n = 57), > 25-50% (n = 30), > 50-75% (n = 7), > 75-100% (n = 2). Increasing Ki-67 expression correlated positively with tumour size, malignancy grade, necrosis, vascular invasion, S-phase fraction, and metastasis. A Ki-67 index Ki-D < or = 10% (n = 86) and > 10% (n = 96) defined two groups who had 84% and 56% 3-year metastasis-free survival (p = 0.0001), respectively. Tumours with Ki-D > 10 were typically large, high grade, necrotic, DNA aneuploid, and had intravascular invasion and a higher S-phase fraction. Ki-67 expression may be helpful in predicting survival of patients with soft tissue sarcomas.