Clinical outcomes and prognostic factors of adult's Ewing sarcoma family of tumors: single center experience

A Nomogram for Predicting Cancer-Specific Survival of Osteosarcoma and Ewing's Sarcoma in Children: A SEER Database Analysis

Background

Osteosarcoma (OSC) and Ewing's sarcoma (EWS) are children's most common primary bone tumors. The purpose of the study is to develop and validate a new nomogram to predict the cancer-specific survival (CSS) of childhood OSC and EWS.

Methods

The clinicopathological information of all children with OSC and EWS from 2004 to 2018 was downloaded from the Surveillance, Epidemiology, and End Results (SEER) database. Univariate and multivariate Cox regression analyses were used to screen children's independent risk factors for CSS. These risk factors were used to construct a nomogram to predict the CSS of children with OSC and EWS. A series of validation methods, including calibration plots, consistency index (C-index), and area under the receiver operating characteristic curve (AUC), were used to validate the accuracy and reliability of the prediction model. Decision curve analysis (DCA) was used to validate the clinical application efficacy of predictive models. All patients were divided into low- and high-risk groups based on the nomogram score. Kaplan-Meier curve and log-rank test were used to compare survival differences between the two groups.

Results

A total of 2059 children with OSC and EWS were included. All patients were randomly divided into training cohort 60% (N = 1215) and validation cohort 40% (N = 844). Univariate and multivariate analysis suggested that age, surgery, stage, primary site, tumor size, and histological type were independent risk factors. Nomograms were established based on these factors to predict 3-, 5-, and 8-years CSS of children with OSC and EWS. The calibration plots showed that the predicted value was highly consistent with the actual value. In the training cohort and validation cohort, the C-index was 0.729 (0.702–0.756) and 0.735 (0.702–0.768), respectively. The AUC of the training cohort and the validation cohort also showed similar results. The DCA showed that the nomogram had good clinical value.

Conclusion

We constructed a new nomogram to predict the CSS of OSC and EWS in children. This predictive model has good accuracy and reliability and can help doctors and patients develop clinical strategies.

What Is the Clinical Importance of Incidental Findings on Staging CT Scans in Patients With Sarcoma?

BACKGROUND

Baseline staging CT scans are performed on nearly every patient after the diagnosis of a sarcoma to evaluate for the presence of metastatic disease. These scans often identify abnormalities that may or may not be related to the known malignancy. Despite the high frequency of incidental findings, there is little guidance for clinicians faced with assessing these radiographic abnormalities. The interpretation of incidental findings is important because it may influence decisions regarding surveillance frequency, prognostic estimation, and surgical and medical intervention.

QUESTIONS/PURPOSES

The purpose of this study was to determine (1) the frequency of abnormal findings and indeterminate nodules on staging CT scans; (2) the natural history of indeterminate nodules identified at the time of sarcoma diagnosis; and (3) the factors associated with indeterminate nodules representing true metastatic disease.

METHODS

Between September 2010 and February 2016 we treated 233 patients with bone and soft tissue sarcomas. Of those, 227 (97%) had a staging CT scan of the chest or chest/abdomen/pelvis performed within 2 months of diagnosis. To be eligible for this retrospective study, a patient had to have a minimum of 6 months of radiographic followup after that initial CT scan. A total of 36 (16%) were lost to followup or did not have radiographic surveillance at least 6 months later, and 48 (21%) were excluded for other prespecified reasons, leaving 149 patients for evaluation. We recorded all abnormal findings listed in the official radiology CT report of the lung, bone, liver, and lymph nodes. We assessed progression of indeterminate nodules by reviewing radiology reports, which listed both size and number of findings, and clinical notes outlining the current assessment of disease status and treatment plan. If indeterminate nodules grew in size or number consistent with metastatic disease or were confirmed histologically, they were considered to represent true metastasis. Bivariate methods were used to investigate an association between various clinical factors, which were obtained from chart review, and progression of indeterminate nodules to clear metastatic disease.

RESULTS

One hundred thirty-five of 149 patients (91%) had at least one abnormal finding on a staging CT scan. Forty-nine patients (33%) presented with indeterminate lung nodules, 15 (10%) with indeterminate liver lesions, four (3%) with indeterminate bone lesions, and 57 (38%) with enlarged lymph nodes. Fifteen of the 49 patients with indeterminate lung nodules (31%), one of 15 liver nodules, zero of four bone lesions, four of 13 lymph nodes 1 to 2 cm in size, and two of 44 subcentimeter lymph nodes (4.5%) were clearly metastatic on followup. A primary tumor size ≥ 14 cm in greatest dimension was more suggestive of indeterminate nodules representing true metastatic disease compared with smaller primary tumors in both lung (eight of 10 compared with seven of 36 [19%]; odds ratio, 16.6; 95% confidence interval, 2.9-95.9; p < 0.001) and lymph nodes (six of 18 compared with zero of 36 [0%], p < 0.001).

CONCLUSIONS

It is extremely common for abnormal findings and incidental nodules to be present at the time of a staging CT scan in patients with sarcoma. Although patients with indeterminate nodules should have continued surveillance, it appears from this study that the majority of these findings do not represent true metastatic disease. Given a minimum followup of 6 months, it is possible the actual proportion of indeterminate lesions representing true metastatic disease may increase over time.

LEVEL OF EVIDENCE

Level III, prognostic study.

Clinical Features and Prognostic Factors in Elderly Ewing Sarcoma Patients

Background

Elderly patients with Ewing sarcoma have a very poor prognosis, and treatment remains a challenge. However, the outcomes and potential prognostic factors of elderly Ewing sarcoma patients are rarely documented. Therefore, we investigated the prognosis of this special cohort and determine independent prognostic factors.

Material/Methods

A cohort of Ewing sarcoma patients aged over 40 years from 1973 to 2015 was identified from the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) database. The Kaplan-Meier method and a Cox proportional hazard regression model were used for the prognostic analysis.

Results

A total of 162 patients were included with a mean age of 53 years. The 5-year overall survival (OS) and cancer-specific survival (CSS) rates of the entire group were 43.7% and 47.9%, respectively. The sex, location, tumor size, and radiation treatment had no effect on survival outcomes on univariate analysis. Tumor stage, surgery, and chemotherapy were significant indicators of both OS and CSS on multivariable analysis.

Conclusions

Surgery in combination with chemotherapy had a significant survival benefit in elderly Ewing sarcoma patients and should be recommended.

Impact of first-line treatment on outcomes of Ewing sarcoma of the spine

The optimal first-line treatment for primary Ewing sarcoma (ES) of the spine is unclear, especially when the patients present with acute neurological deficits. This study aimed to retrospectively analyze the effect of first-line treatment with surgery or chemotherapy on neurological and survival outcomes of ES of the spine. 39 patients treated between January 2005 and December 2016 were included in the present analysis. 29 (74.4%) presented with symptomatic spinal cord compression at diagnosis. 21 patients were submitted to primary surgery followed by chemotherapy and local radiotherapy, while 18 patients received induction chemotherapy before surgery and/or local radiotherapy. Neurological deficit before and after treatment, event-free survival and overall survival were analyzed. The results indicated that chemotherapy as the first-line treatment could achieve similar results as primary surgery in preserving neurological function, even in case of major neurological deficits. Compared with primary surgery, induction chemotherapy contributed to a higher rate of en bloc resection with a microscopic negative margin (R0) of primary tumor (72.7% vs. 28.6%, P < 0.05). Multivariate Cox regression analyses revealed that initial chemotherapy was a favorable independent prognostic factor of event-free survival (hazard ratio, 0.215; 95% confidence interval, 0.077-0.596; P = 0.003) and overall survival (hazard ratio, 0.288, 95% confidence interval, 0.098-0.852; P = 0.024). In conclusion, our study suggests that first-line treatment of ES of the spine should be induction chemotherapy, even in case of major neurological deficits.

Immunohistochemical analysis and prognostic significance of PD-L1, PD-1, and CD8+ tumor-infiltrating lymphocytes in Ewing's sarcoma family of tumors (ESFT)

Ewing's sarcoma family of tumors (ESFT) are aggressive neoplasms with scant tumor-infiltrating lymphocytes. We analyzed the immunohistochemical (IHC) expression of PD-L1 and PD-1 and their prognostic significance in clinically localized neoplasms in a cohort of 370 ESFT. Slides prepared from tissue microarrays were stained for PD-L1, PD-1, and CD8. Membranous/cytoplasmic staining over 5% of tumor cells was regarded as positive for PD-L1 and PD-1. Prognostic analysis was done considering only clinically localized tumors (n = 217). PD-L1 expression was present in 19% of ESFT, while PD-1 was expressed in 26%. Forty-eight percent of tumors were negative and 12% were positive for both PD-L1 and PD-1. Metastatic tumors displayed higher expression of PD-L1 (p < 0.0001). Histological subtypes were not correlated with PD-L1 or PD-1 positivity. ESFT with elevated proliferation index (Ki-67) were associated with higher PD-L1 expression (p = 0.049). Regarding prognosis, no significant association was found between PD-L1 expression and progression-free survival (PFS) or overall survival (OS), whereas lack of PD-1 expression in tumor cells was correlated with both poor PFS (p = 0.02) and poor OS (p = 0.004). Tumor-infiltrating CD8(+) T lymphocytes were observed in 15.4% of ESFT with informative results (347 tumors). No correlation was found between tumor-infiltrating CD8(+) T lymphocytes and ESFT histological subtypes, tumor location, or PD-1 and PD-L1 expression, nor with PFS (p = 0.473) or OS (p = 0.087). PD-L1 expression was not significantly related to prognosis. PD-1 was expressed in 26% of ESFT tumor cells and may have prognostic and therapeutic implications. CD8 expression in tumor-infiltrating lymphocytes was not related to prognosis.