PROX1 transcription factor controls rhabdomyosarcoma growth, stemness, myogenic properties and therapeutic targets.

Rhabdomyosarcoma (RMS) is an aggressive pediatric soft-tissue cancer with features of skeletal muscle. Because of poor survival of RMS patients and severe long-term side effects of RMS therapies, alternative RMS therapies are urgently needed. Here we show that the prospero-related homeobox 1 (PROX1) transcription factor is highly expressed in RMS tumors regardless of their cell type of origin. We demonstrate that PROX1 is needed for RMS cell clonogenicity, growth and tumor formation. PROX1 gene silencing repressed several myogenic and tumorigenic transcripts and transformed the RD cell transcriptome to resemble that of benign mesenchymal stem cells. Importantly, we found that fibroblast growth factor receptors (FGFR) mediated the growth effects of PROX1 in RMS. Because of receptor cross-compensation, paralog-specific FGFR inhibition did not mimic the effects of PROX1 silencing, whereas a pan-FGFR inhibitor ablated RMS cell proliferation and induced apoptosis. Our findings uncover the critical role of PROX1 in RMS and offer insights into the mechanisms that regulate RMS development and growth. As FGFR inhibitors have already been tested in clinical phase I/II trials in other cancer types, our findings provide an alternative option for RMS treatment.

Patterns of Metastatic Recurrence of Genetically Confirmed Myxoid Liposarcoma.

BACKGROUND: Most sarcomas metastasize predominantly to the lungs, and chest x-ray, or computed tomography, is the most commonly used staging investigation. Myxoid liposarcomas (MLSs) are rare tumors with a tendency to metastasize to extrapulmonary loci. The aim of this study was to assess the locations of the first metastases in MLS patients, to guide the design of effective staging and follow-up imaging protocols. METHODS: Patients treated for MLS between 1987 and 2017 were identified in a prospectively maintained register. Histology of the tumors was reassessed. In addition, the presence of one of the pathognomonic gene translocations was confirmed, uniquely for a retrospective series. The surgical and oncological outcomes were reviewed. A comprehensive review of the literature was performed on the metastatic pattern of MLS, including series with 10 or more MLS patients with metastatic disease. RESULTS: A total of 32 patients with genetically confirmed MLS were identified, with a median follow-up of 7.6 years. Seven patients (22%) developed metastatic disease, five initially intra-abdominally and only one to the lungs. The comprehensive review included 14 series with 1853 patients, 348 (19%) of whom had metastases. The location of the first metastases was soft tissues in 32% of patients, intra-abdominal in 26%, pulmonary in 24%, and bone in 17%. CONCLUSIONS: MLSs metastasize often intra-abdominally and to extra-abdominal soft tissues. Thus, whole-body imaging may be indicated during the initial assessment and follow-up of these patients.

Radiation-associated angiosarcoma of the breast: analysis of diagnostic tools in a registry-based population.

BACKGROUND: Radiation-associated angiosarcoma of the breast (RAASB) is a serious late consequence caused by breast cancer treatment. Initial symptoms are often inconspicuous, thus contributing to diagnostic delay. Most previous studies of the diagnostic aspects of RAASB are case reports. PURPOSE: To perform a complete review of the imaging findings and biopsy methods in a nationwide RAASB cohort. MATERIAL AND METHODS: RAASB patients were identified from a national cancer registry and additional patients were included from our hospital. All available information from imaging (mammogram [MGR], ultrasound [US], magnetic resonance imaging [MRI], and computed tomography [CT]) and biopsies was reviewed. The sensitivity of imaging and biopsy methods for detection of RAASB was calculated. RESULTS: Fifty-eight patients with RAASB were found. Fourteen MGR, 30 US, 24 MRI, and 25 CT studies were available for evaluation. The sensitivity of MGR, US, MRI, and CT for detection of RAASB was 43%, 50%, 92%, and 84%, respectively. Superior sensitivity was demonstrated for punch biopsy (84%) and incisional biopsy (93%) compared to fine-needle aspiration cytology (0%) and core needle biopsy (18%). CONCLUSION: MRI and CT have comparable sensitivity for detection of RAASB, while MGR and US are unreliable. However, negative findings in MRI or CT must be interpreted with caution. Punch biopsy and incisional biopsy are the preferred biopsy methods.

Expression of markers of stem cell characteristics, epithelial-mesenchymal transition, basal-like phenotype, proliferation, and androgen receptor in metaplastic breast cancer and their prognostic impact.

BACKGROUND: Metaplastic breast cancer (MpBC) is a heterogeneous subtype of invasive mammary carcinoma associated with epithelial-mesenchymal transition (EMT) and cancer stem cell characteristics. Data regarding prognostic markers and potentially actionable targets for therapy are still limited. The present study aimed to characterize the immunohistochemical landscape of this rare malignancy and to identify potential prognostic factors and targets for therapy. MATERIAL AND METHODS: A total of 75 patients diagnosed with MpBC over a 15-year period were included in the study. We performed immunohistochemical analyses for Ki-67 (MIB-1), epidermal growth factor receptor (EGFR), cytokeratin 5/6, vimentin, CD44, and androgen receptor (AR) and correlated their expression with clinicopathologic features and clinical outcomes. The p-values for survival analyses were corrected for multiple testing (threshold 0.01). RESULTS: Most tumors expressed CK5/6 (73%), EGFR (59%), CD44 (81%), and vimentin (87%). Eighty-nine percent had a high Ki-67 index. Eighty-four percent were classified as basal-like (CK 5/6 or EGFR positive). AR was expressed in 21% of the tumors. The basal-like phenotype was significantly (p = 0.009) associated with inferior disease-free (DFS) and breast-cancer-specific overall survival (BCOS) with borderline significance (p = 0.01). In addition, a low Ki-67 index was associated with improved DFS (p = 0.033) and BCOS (p = 0.03). CONCLUSION: Most MpBCs express basal markers (CK5/6, EGFR), epithelial-mesenchymal transition marker vimentin, and the stem cell marker CD44. Expression of basal-like markers was significantly related to inferior DFS. All the 11 patients with a lack of expression of basal markers survived without relapse.

Structural validity of the Finnish Manchester-Oxford Foot Questionnaire (MOXFQ) using the Rasch model.

BACKGROUND: The 16-item patient-reported Manchester-Oxford Foot Questionnaire (MOXFQ) with subscales of pain, social interactions, and walking/standing has been claimed for strongest scientific evidence in measuring foot and ankle complaints. This study tests the validity of the Finnish MOXFQ for orthopaedic foot and ankle population using the Rasch analysis. METHODS: We translated the MOXFQ into Finnish and used that translation in our study. MOXFQ scores were obtained from 183 patients. Response category distribution, item fit, coverage, targeting, item dependency, ability to measure latent trait (unidimensionality), internal consistency (Cronbach's alpha), and person separation index (PSI) were analyzed. RESULTS: Fifteen of the items had ordered response categories and/or sufficient fit statistics. The subscales provided coverage and targeting. Some residual correlation was noted. Removing one item in the pain subscale led to a unidimensional structure. Alphas and PSIs ranged between 0.68-0.90 and 0.67-0.92, respectively. CONCLUSIONS: Despite some infractions of the Rasch model, the instrument functioned well. The subscales of the MOXFQ are meaningful for assessing patient-reported complaints and outcomes in orthopaedic foot and ankle population.

Validity of five foot and ankle specific electronic patient-reported outcome (ePRO) instruments in patients undergoing elective orthopedic foot or ankle surgery.

BACKGROUND: Patient-reported outcomes (PROs) are widely accepted measures for evaluating outcomes of surgical interventions. As patient-reported information is stored in electronic health records, it is essential that there are valid electronic PRO (ePRO) instruments available for clinicians and researchers. The aim of this study was to evaluate the validity of electronic versions of five widely used foot and ankle specific PRO instruments. METHODS: Altogether 111 consecutive elective foot/ankle surgery patients were invited face-to-face to participate in this study. Patients completed electronic versions of the Foot and Ankle Ability Measure (FAAM), the Foot and Ankle Outcome Score (FAOS), the modified Lower Extremity Function Scale (LEFS), the Manchester-Oxford Foot Questionnaire (MOXFQ), and the Visual Analogue Scale Foot and Ankle (VAS-FA) on the day of elective foot and/or ankle surgery. Construct validity, coverage, and targeting of the scales were assessed. RESULTS: Based on general and predefined thresholds, construct validity, coverage, and targeting of the ePRO versions of the FAAM, the FAOS, the MOXFQ, and the VAS-FA were acceptable. Major issues arose with score distribution and convergent validity of the modified LEFS instrument. CONCLUSIONS: The ePRO versions of the FAAM, the FAOS, the MOXFQ, and the VAS-FA provide valid scores for foot and ankle patients. However, our findings do not support the use of the modified LEFS as an electronic outcome measure for patients with orthopedic foot and/or ankle pathologies.

Treatment and Prognosis of Radiation-Associated Breast Angiosarcoma in a Nationwide Population.

BACKGROUND: Radiation-associated angiosarcoma of the breast (RAASB) is an aggressive malignancy that is increasing in incidence. Only a few previous population-based studies have reported the results of RAASB treatment. METHODS: A search for RAASB patients was carried out in the Finnish Cancer Registry, and treatment data were collected to identify prognostic factors for survival. RESULTS: Overall, 50 RAASB patients were identified. The median follow-up time was 5.4 years (range 0.4-15.6), and the 5-year overall survival rate was 69%. Forty-seven (94%) patients were operated on with curative intent. Among these patients, the 5-year local recurrence-free survival, distant recurrence-free survival, and overall survival rates were 62%, 75%, and 74%, respectively. A larger planned surgical margin was associated with improved survival. CONCLUSIONS: We found that the majority of RAASB patients were eligible for radical surgical management in this population-based analysis. With radical surgery, the prognosis is relatively good.

Single centre 30-year experience in treating retroperitoneal liposarcomas.

BACKGROUND AND OBJECTIVES: Liposarcomas form a diverse group of tumors that represent the majority of retroperitoneal soft tissue sarcomas. Radical excision of these retroperitoneal liposarcomas is often challenging due to their large size and proximity to visceral organs and major vessels. Here we present the 30-year experience of our multidisciplinary sarcoma team in the treatment of these tumors and analysis of factors influencing survival. METHODS: Patients with retroperitoneal liposarcomas treated in Helsinki University Hospital from 1987 to 2017 were reviewed. Local recurrence-free survival, metastases-free survival, and disease-specific survival were assessed with Kaplan-Meier analysis, and factors influencing survival were evaluated with Cox regression. RESULTS: A total of 107 patients were identified. The median follow-up time was 5.4 years (interquartile range: 2.2-8.8 years). Local recurrence developed in 72% and metastases in 15% during follow-up. The 5-year disease-free survival was 31% and disease-specific survival was 66%. The multifactorial analysis revealed histological type and grade as predictors of disease-specific survival (P < .01) while multifocality carried a poor prognosis for local recurrence (P = .02) and higher histological grade for metastases (P < .01). CONCLUSIONS: Retroperitoneal liposarcomas rarely metastasize but tend to recur locally. For tumors that have been resected with macroscopically clear margins, histological, type, and grade are significant predictors of survival.

Multidisciplinary Oncovascular Surgery is Safe and Effective in the Treatment of Intra-abdominal and Retroperitoneal Sarcomas: A Retrospective Single Centre Cohort Study and a Comprehensive Literature Review.

OBJECTIVE: Radical excision of retroperitoneal or intra-abdominal soft tissue sarcomas may necessitate vessel resection and reconstruction. The aim of this study was to assess surgical results of retroperitoneal or intra-abdominal sarcomas involving major blood vessels. METHODS: This was a retrospective single centre cohort study and a comprehensive review of literature. Patients with retroperitoneal or intra-abdominal sarcomas treated by the oncovascular team in Helsinki University Hospital from 2010 to 2018 were reviewed for vascular and oncological outcomes. A comprehensive literature review of vascular reconstructions in patients with retroperitoneal sarcoma was performed. RESULTS: Vascular reconstruction was performed in 17 patients, 11 of whom required arterial reconstructions. Sixteen of the operations were sarcoma resections; the post-operative diagnosis for one patient was thrombosis instead of the presumed recurrent leiomyosarcoma. Early graft thrombosis occurred in two venous and one arterial reconstruction. Late thrombosis was detected in three (18%). The median follow up was 27 (range 0-82) months. Of the patients with sarcoma resections 5 (31%) died of sarcoma and further 4 (25%) developed local recurrence or new distant metastases. The comprehensive review of literature identified 37 articles with 110 patients, 89 of whom had inferior vena cava reconstruction only. Eight arterial reconstructions were described. Late graft thrombosis occurred in 14%. The follow up was 0-181 months, during which 57% remained disease free and 7% died of sarcoma. CONCLUSION: Vascular reconstructions enable radical resection of retroperitoneal and intra-abdominal sarcomas in patients with advanced disease. The complex operations are associated with an acceptable rate of serious peri-operative complications and symptomatic thrombosis of the repaired vessel is rare. However, further studies are needed to assess the performance of the vascular reconstructions in the long term.

Long-term results of surgical resection of lung metastases from soft tissue sarcoma: A single center experience.

BACKGROUND: A single-institution experience of pulmonary metastasectomy in soft tissue sarcoma (STS) was retrospectively reviewed. Our specific aim was to examine, whether the resection of pulmonary metastases could be curative. We also compared overall survival (OS) of patients after complete or incomplete pulmonary resection and nonsurgical treatment. METHODS: Between 1987 and 2016, 1580 patients were treated for STS with curative intent by Soft Tissue Sarcoma Group at Helsinki University Hospital, Finland. Three hundred forty-seven patients (22%) developed advanced disease and 130 STS patients (9%) developed pulmonary metastases as first systemic relapse. Seventy four patients (5%) were operated for lung metastases. RESULTS: Fifty-five patients (42%) had a complete and 19 (15%) incomplete resection. Fifty-six (43%) were unoperated. Median OS after complete or incomplete metastasectomy, chemotherapy, or best supportive care was 22, 18, 8, and 5 months, respectively. Twelve patients (9%) developed no further metastases and are alive with no evidence of disease. Disease-free survival (DFS) for completely resected patients was 17% at 5 years. All long-term survivors had oligometastatic disease and they underwent one to three complete metastasectomies. CONCLUSIONS: Complete pulmonary metastasectomy in STS results in 5 years DFS in nearly one-fifth of patients. Most of these patients are probably cured.

Estrogen receptor beta expression correlates with proliferation in desmoid tumors.

BACKGROUND AND OBJECTIVES: Estrogen receptor signaling and cyclin D1 have a major role in tumor cell proliferation in breast cancer. Desmoid tumors are rare neoplasms that may respond to endocrine treatment. The present study aimed to investigate the expression levels and the clinical relevance of estrogen receptor beta (ERß) and cyclin D1 in desmoid tumors. METHODS: This study consists of 83 patients with a surgically treated desmoid tumor. ERß and cyclin D1 expression was examined by immunohistochemistry in tissue microarrays. Cyclin A and Ki67 were studied in our previous work. RESULTS: Median ERß expression was 10.8%. ERß expression correlated with expression of the proliferation antigens Ki67 (rp = 0.35, P = 0.003), cyclin D1 (rp = 0.34, P = 0.004), and cyclin A (rp = 0.34, P = 0.004). ERß immunoexpression showed a trend towards predictive impact for recurrence as a continuous variable. Further explorative analysis indicated that very high ERß expression was related to high risk of relapse (hazard ratio [HR] 2.6; P = 0.02). Median cyclin D1 expression was 15.6%. High cyclin D1 expression was associated with high Ki67 and cyclin A expression. Cyclin D1 was not associated with time to recurrence. CONCLUSIONS: ERß and cyclin D1 immunopositivity correlated with high proliferation in desmoid tumors. High ERß expression might be predictive for postoperative recurrence.

Improved prognosis in soft-tissue sarcoma of extremity and trunk wall.

Background and purpose - Soft-tissue sarcoma (STS) is rare, with challenging individualized treatment, so diagnostics and treatment should be centralized. Historical controls are sometimes used for investigation of whether new diagnostic or therapeutic tools affect patient outcome. However, as yet unknown factors may affect the outcome. We investigated prognostic factors and prognosis in 2 nationwide cohorts of patients diagnosed with a local STS during the periods 1998-2001 and 2005-2010, with special interest in finding factors lying behind possible improvement of prognosis. Patients and methods - 2 cohorts of patients with STS of the extremities or trunk diagnosed during the periods 1998-2001 and 2005-2010 were retrieved from the nationwide Finnish Cancer Registry. Detailed information was gathered from patient files. Results - Compared to first cohort, a larger proportion of patients with inadequate surgery in the second cohort received radiation therapy, and both the local control rate and the sarcoma-specific survival rate improved in the second cohort. For sarcoma-specific survival, cohort (HR =0.6, 95% CI: 0.5-0.9), age, depth, grade, and margin were significant factors in multivariate analysis. For local control, cohort (HR =0.6, 95% CI: 0.5-0.9), age, and margin were significant in multivariate analysis. Interpretation - Known prognostic factors including type of treatment did not entirely explain the secular trend of continuous improvement in prognosis in STS. This illustrates the danger of using historical controls for investigation of whether new diagnostic or therapeutic tools have an effect on patient outcome.

The Scandinavian Sarcoma Group Central Register: 6,000 patients after 25 years of monitoring of referral and treatment of extremity and trunk wall soft-tissue sarcoma.

Purpose - We wanted to examine the potential of the Scandinavian Sarcoma Group (SSG) Central Register, and evaluate referral and treatment practice for soft-tissue sarcomas in the extremities and trunk wall (STS) in the Nordic countries. Background - Based on incidence rates from the literature, 8,150 (7,000-9,300) cases of STS of the extremity and trunk wall should have been diagnosed in Norway, Finland, Iceland, and Sweden from 1987 through 2011. The SSG Register has 6,027 cases registered from this period, with 5,837 having complete registration of key variables. 10 centers have been reporting to the Register. The 5 centers that consistently report treat approximately 90% of the cases in their respective regions. The remaining centers have reported all the patients who were treated during certain time periods, but not for the entire 25-year period. Results - 59% of patients were referred to a sarcoma center untouched, i.e. before any attempt at open biopsy. There was an improvement from 52% during the first 5 years to 70% during the last 5 years. 50% had wide or better margins at surgery. Wide margins are now achieved less often than 20 years ago, in parallel with an increase in the use of radiotherapy. For the centers that consistently report, 97% of surviving patients are followed for more than 4 years. Metastasis-free survival (MFS) increased from 67% to 73% during the 25-year period. Interpretation - The Register is considered to be representative of extremity and trunk wall sarcoma disease in the population of Scandinavia, treated at the reporting centers. There were no clinically significant differences in treatment results at these centers.

Incidence, treatment and survival of paediatric patients with bone sarcomas in Finland from 1991 to 2005.

AIM: Our aims were to establish the 10-year overall and event-free survival rates among children and adolescents with bone sarcomas in Finland, estimate their respective incidences, evaluate the treatment given and describe the key prognostic factors. METHODS: We included 88 patients of <18 years of age diagnosed with a bone sarcoma during 1991-2005 in this retrospective, nationwide and population-based study. Median follow-up time was 12.2 years (range 5.8-20.3 years) for surviving patients. RESULTS: The overall incidence among children and adolescents was 5.1 per million: 3.6 for osteosarcoma, 1.2 for Ewing's sarcoma and 0.3 for chondrosarcoma. The 10-year event-free and overall survival of those with a localised disease at diagnosis was 69% and 82%, respectively. The overall 10-year survival of those with a metastatic disease at diagnosis was 47%. Prognostic factors for localised disease included an axial versus peripheral primary tumour site in Ewing's sarcoma (p = 0.022) and age at diagnosis in osteosarcoma (p = 0.027). CONCLUSION: The 10-year overall survival of children and adolescents diagnosed with a bone sarcoma in Finland during 1991 to 2005 was very good, at 82% if the disease was localised at diagnosis and 47% if it was metastatic at diagnosis.

[Oncologic therapy of soft tissue sarcoma]. / Pehmytkudossarkooman onkologinen hoito.

Surgery with a margin of resection is the only curative form of treatment of soft tissue sarcoma. The combination of surgery and radiotherapy can, however, be used to lower the risk of local recurrence, if wide margins are not achieved e.g. in order to preserve the function of a limb. By using combination chemotherapy, disease recurrence can in the highest-risk patients be decreased to some extent. Radiotherapy provides palliative relief from a number of the patient's symptoms. The diagnosis and treatment of soft tissue sarcoma require an early participation of a multidisciplinary team familiarized with these rare tumors.

Marginal miss or radioresistance? The pattern of local recurrence after operation and 3D planned radiation treatment in soft tissue sarcoma of the extremities and the limb girdles; an analysis based on image fusion.

BACKGROUND: Most local recurrences have developed in the clinical target volume in previously published series after combined modality treatment for soft tissue sarcoma. However, marginal misses were seen in almost 20% of the patients. The aim of the present study was to determine the location of the recurrence and the total dose at the centre point of the local recurrence for future radiation therapy planning. MATERIAL AND METHODS: We included only patients with images in digital form, during 1999-2006 (n = 17), treated for soft tissue sarcoma with combined surgical therapy and radiotherapy at Helsinki University Central Hospital. Image fusion was used to determine the location of the recurrence in relation to radiation therapy target. RESULTS: In the present study utilising digital image fusion, in patients with 3D CT-based radiation treatment planning the risk of marginal miss was low as only one patient of 17 relapsed outside the target. Estimated mean radiation dose at the site of local recurrence was 49.1 Gy in patients with positive margins and 48.1 Gy in patients with negative margins. CONCLUSION: The risk of marginal miss in soft tissue sarcoma is low after modern 3D planned radiation treatment combined with surgery. More generous use of boost might improve in-target local control.

A Retrospective Analysis of Systemic Oncologic Treatment in Older Patients With Advanced Soft-tissue Sarcoma.

BACKGROUND/AIM: Almost half of all patients with soft-tissue sarcoma are over 65 years of age, and the proportion of older patients is increasing. Despite this, they have been underrepresented in clinical trials and only limited data are available to guide treatment decisions. The aim of this study was to investigate treatment patterns and outcomes in older patients with soft-tissue sarcoma. PATIENTS AND METHODS: Patients over 50 years old treated for advanced soft-tissue sarcoma at the Helsinki University Hospital between January 2000 and July 2020 were included. Data on patient and tumor characteristics, treatment, and survival were retrospectively collected. A total of 152 patients were included: 14.5% (n=22) were over 75 years old, 34.2% (n=52) were 65-74 and 51.3% (n=78) were 50-64 years old. RESULTS: The outcomes of the oldest group differed from those of younger patients; they were more likely to receive single-agent treatment as first-line therapy (90.9% vs. 28.8% and 24.4%, p<0.001) and had the lowest relative dose-intensity (70% vs. 88% and 95%, p<0.05). They experienced grade three to four hematological adverse events less frequently (38.1%, 56.9% and 72.7%, respectively, p=0.031), and received fewer lines of treatment (median of 1, 2 and 2, respectively, p=0.01). In patients aged ≥75 years, there was no association between further lines of therapy and improved survival. Compared to the youngest group, the oldest patients had a greater risk of dying (hazard ratio=1.7, 95% confidence interval=1.0-2.8, p=0.041) and their median overall survival was only 7.4 months, compared to 14.3 and 12.9 months in the two younger groups. CONCLUSION: These findings suggest that older patients tolerate chemotherapy when treatment is tailored to their needs but may not benefit as much as younger patients.

Ultra-low-dose computed tomography and chest X-ray in follow-up of high-grade soft tissue sarcoma-a prospective comparative study.

Ultra-low-dose computed tomography (ULD-CT) may combine the high sensitivity of conventional computed tomography (CT) in detecting sarcoma pulmonary metastasis, with a radiation dose in the same magnitude as chest X-ray (CXR). Fifty patients with non-metastatic high-grade soft tissue sarcoma treated with curative intention were recruited. Their follow-up involved both CXR and ULD-CT to evaluate their different sensitivity. Suspected findings were confirmed by conventional CT if necessary. Patients with isolated pulmonary metastases were treated with surgery or stereotactic body radiation therapy (SBRT) with curative intent if possible. The median effective dose from a single ULD-CT study was 0.27 mSv (range 0.12 to 0.89 mSv). Nine patients were diagnosed with asymptomatic lung metastases during the follow-up. Only three of them were visible in CXR and all nine in ULD-CT. CXR had therefore only a 33% sensitivity compared to ULD-CT. Four patients were operated, and one had SBRT to all pulmonary lesions. Eight of them, however, died of the disease. Two patients developed symptomatic metastatic recurrence involving extrapulmonary sites+/-the lungs between two imaging rounds. ULD-CT has higher sensitivity for the detection of sarcoma pulmonary metastasis than CXR, with a radiation dose considerably lower than conventional CT.Clinical trial registration: NCT05813808. 04-14-2023.

Ewing's sarcoma family of tumors in Finland during 1990-2009: a population-based study.

BACKGROUND: Ewing's sarcoma family of tumors (ESFTs) are rare bone and soft tissue tumors characterized by specific genetic alterations. Our aim was to carry out a nationwide analysis of ESFT, to survey the treatments used and to report the five-year disease specific and event-free survival rates (EFS and DSS). MATERIAL AND METHODS: The study data was gathered from the Finnish National Cancer Registry and all five University Hospitals and consisted of 76 bone and soft tissue ESFT patients diagnosed during 1990-2009. Their medical records were reviewed and data on their disease, treatments, complications and outcome were analyzed. RESULTS: The five-year EFS and DSS of patients with localized disease at diagnosis (n = 57) were 70% and 60%, respectively. Factors contributing to DSS and EFS were the axial vs. peripheral site of primary tumor and adequate surgical resection of the primary tumor. DSS was also affected by patient's age at diagnosis and the treatment employed. The five-year DSS of patients with metastatic disease at diagnosis (n = 19) was 33% and both preoperative and high dose chemotherapy were associated with improved survival. CONCLUSION: Population-based studies including both bone and soft tissue ESFTs are few. In this nationwide, population-based study on Finnish bone and soft tissue ESFT patients, we find their treatment successful and results comparable to those previously published. Absence of metastases, young age at diagnosis and a peripheral primary tumor site were associated with a better prognosis. It seems that surgical resection of the primary tumor should be performed whenever adequate resection margins can be achieved. The role of high dose chemotherapy merits further studies in this setting.