Demographic characteristics and prognostic factors in pediatric-type sarcomas; A 7 year single institutional experience and comprehensive review of the current literature

Background: due to limited clinical data in pediatric-type sarcomas [rhabdomyosarcoma, Ewing's sarcoma, PNET, and desmoplastic small round-cell tumor], the aim of this study was to evaluate the demographic characteristics and identifying prognostic factors for survival

Materials and Methods: we retrospectively reviewed 110 patients with pediatric-type sarcomas. Overall and disease free survival was analyzed with the Kaplan-Meier method and log rank test. To identify prognostic factors for overall and disease free survival, multivariate survival analyses using a Cox's proportional-hazard regression model was performed

Results: in this study mean age of patients were 20.30 years [SD=13.61; range, 1-83 years]. The survival data of 54 patients [49.1%] were obtained with median survival of 27 months. 3 and 5-year survival rate of these patients were 41.5% and 28.3% respectively. Recurrence of disease [P=0.006] and Ewing sarcoma subtype [P=0.018] were significantly associated with poor overall survival and location of the lesion in the upper extremities [P=0.007] and trunk [P=0.005] were significantly associated with a lower disease free survival

Conclusion: with multivariate analysis, the authors determined that recurrence of disease and Ewing's sarcoma subtype are poor prognostic factors for overall survival and site of origin for disease free survival among patients with pediatric-type sarcoma. In addition, gender, patient's age, and size of tumor had no significant impact on overall and disease free survival

Radiotherapy for Ewing sarcoma: a 5 year experience from Iran cancer institute

Background: Ewing Sarcoma Family of Tumors [ESFTs] is the second most common primary tumors of bone in childhood. The decision regarding the optimal modality for achieving local tumor control remains uncertain. The aim of this study was to report the clinical features and outcome as well as reviewing risk factors in patients. Materials and Methods: This retrospective study included 75 ESFTs patients who were treated at cancer institute between 2004 and 2009. Files of all patients with ESFTs were reviewed retrospectively and we called them for follow up. Specific data were collected with regard to the age at diagnosis, gender, tumor site and size, clinical stage, surgical procedure, plan of radiotherapy and treatment outcome [5-year and median survival]. Results: The mean age at diagnosis was 21 that ranged from 1 to 52 years [SD = 9.6]. The mean tumor size at diagnosis was 4.8+/-4.48 cm. The percent of biopsy only, partial and complete resection was 54.7% [41 patients], 6.7% [5 patients] and 37.3% [28 patients] respectively. Radiotherapy was done as definitive treatment or postoperatively [adjuvant] in 46 [61.3%] and 16 [21.4%] patients respectively. Overall 5 year survival was 24% and median survival for patients with and without metastases was 21+/-17 and 75+/-10 months. Conclusion: Presence of metastases, age at diagnosis, positive surgical margin and tumor size were the prognostic factors that influenced outcome of patients. This study suggests that radiation therapy is an acceptable local treatment modality in patients with Ewing sarcoma family

Dose measurement outside of radiotherapy treatment field [Peripheral dose] using thermoluminesent dosimeters

In radiation therapy, peripheral dose or the dose outside the radiotherapy field, is important when anatomical structures with very low dose tolerances are involved. One of these critical organs in pelvic irradiation is testis. The amount of radiation delivered to the testes in radiotherapy must be kept as small as possible, consistent with the limit dose of this organ. The threshold doses for temporary and permanent sterility are 0.15 Gy and 6-8 Gy, respectively. Therefore, in pelvic irradiation, protecting testis from these doses and also scattered radiation which could escalate testis dose should be considered. In order to determine the possibility of using testicular shield for high and low energies, TLD dosimetry was done on phantom and 27 patients involved with bladder, rectum and prostate cancers. Dosimetric results showed that the ability of testicular shield in reducing testes absorbed dose is approximately the same [about 7 cGy] for low and high energy photon beams. a testicular shield with a fixed thickness of 1.27cm can be used as testis protection for either high and low energies