Significance of fusion status, Oberlin risk factors, local and maintenance treatment in pediatric and adolescent patients with metastatic rhabdomyosarcoma: Data of the European Soft Tissue Sarcoma Registry SoTiSaR

BACKGROUND

Outcome of primary metastatic rhabdomyosarcoma (RMS) is poor. Certain risk factors as fusion status, Oberlin score, and local treatment of primary tumor are known to influence prognosis.

PROCEDURE

Patients with metastatic RMS were treated according to Cooperative Weichteilsarkom Studiengruppe (CWS) guidance with chemotherapy (CHT), radiotherapy (RT) excluding total lung irradiation (TLI), complete resection of the primary tumor, and metastasectomy if possible. Kaplan-Meier estimators and Cox proportional hazard models were used to examine event-free survival (EFS) and overall survival (OS) involving also landmark analyses.

RESULTS

In the European Soft Tissue Sarcoma Registry SoTiSaR (2009-2018), 211 patients were analyzed. Many patients had fusion-positive alveolar RMS (n = 83; 39%). Median age was 9.4 years [0.1-19.7 years]. Treatment primarily consisted of CHT with CEVAIE (carboplatin, epirubicine, vincristine, actinomycin-D, ifosfamide, etoposide: 86%, other regimens: 14%), RT (71%), resection of primary tumor (37%), metastasectomy (19%), and lymph node sampling/dissection (21%). Maintenance treatment (MT) (oral trofosfamide, idarubicin, etoposide) was added in 74% of patients. Oberlin factors, fusion status, and MT were predictive for EFS and OS. MT with O-TIE was not improving outcome when adjusting for the immortal time bias. Local treatment of the primary tumor and radical irradiation (except TLI) improved EFS, not OS, when adjusting for the Oberlin score. Patients with fusion-negative alveolar RMS (n = 9) had an excellent outcome with a 5-year EFS and OS of 100%, compared to patients with embryonal RMS (49%/62%), PAX7- (22%/47%) and PAX3/FOXO1-positive ARMS (10/13%), respectively (p < .001).

CONCLUSIONS

Prognosis of metastatic RMS primarily depends on fusion status and Oberlin score. Fusion status needs to be considered in future trials to optimize treatment outcome. The role of radical irradiation needs further investigation.

Refinement of risk stratification for childhood rhabdomyosarcoma using FOXO1 fusion status in addition to established clinical outcome predictors: A report from the Children's Oncology Group

Background

Previous studies of the prognostic importance of FOXO1 fusion status in patients with rhabdomyosarcoma (RMS) have had conflicting results. We re‐examined risk stratification by adding FOXO1 status to traditional clinical prognostic factors in children with localized or metastatic RMS.

Methods

Data from six COG clinical trials (D9602, D9802, D9803, ARST0331, ARTS0431, ARST0531; two studies each for low‐, intermediate‐ and high‐risk patients) accruing previously untreated patients with RMS from 1997 to 2013 yielded 1727 evaluable patients. Survival tree regression for event‐free survival (EFS) was conducted to recursively select prognostic factors for branching and split. Factors included were age, FOXO1, clinical group, histology, nodal status, number of metastatic sites, primary site, sex, tumor size, and presence of metastases in bone/bone marrow, soft tissue, effusions, lung, distant lymph nodes, and other sites. Definition and outcome of the proposed risk groups were compared to existing systems and cross‐validated results.

Results

The 5‐year EFS and overall survival (OS) for evaluable patients were 69% and 79%, respectively. Extent of disease (localized versus metastatic) was the first split (EFS 73% vs 30%; OS 84% vs. 42%). FOXO1 status (positive vs negative) was significant in the second split both for localized (EFS 52% vs 78%; OS 65% vs 88%) and metastatic disease (EFS 6% vs 46%; OS 19% vs 58%).

Conclusions

After metastatic status, FOXO1 status is the most important prognostic factor in patients with RMS and improves risk stratification of patients with localized RMS. Our findings support incorporation of FOXO1 status in risk stratified clinical trials.

Histology, fusion status, and outcome in metastatic rhabdomyosarcoma: A report from the Children's Oncology Group

BACKGROUND

Distinguishing alveolar rhabdomyosarcoma (ARMS) from embryonal rhabdomyosarcoma (ERMS) has historically been of prognostic and therapeutic importance. However, classification has been complicated by shifting histologic criteria required for an ARMS diagnosis. Children's Oncology Group (COG) studies after IRS-IV, which included the height of this diagnostic shift, showed both an increased number of ARMS and an increase in the proportion of fusion-negative ARMS. Following diagnostic standardization and histologic re-review of ARMS cases enrolled during this era, analysis of low-risk (D9602) and intermediate-risk (D9803) rhabdomyosarcoma (RMS) studies showed that fusion status rather than histology best predicts prognosis for patients with RMS. This analysis remains to be completed for patients with high-risk RMS.

PROCEDURE

We re-reviewed cases on high-risk COG studies D9802 and ARST0431 with an enrollment diagnosis of ARMS. We compared the event-free survival (EFS) and overall survival by histology, PAX-FOXO1 fusion, and clinical risk factors (Oberlin score) for patients with metastatic RMS using the log-rank test.

RESULTS

Histology re-review resulted in reclassification as ERMS for 12% of D9802 cases and 5% of ARST0431 cases. Fusion-negative RMS had a superior EFS to fusion-positive RMS; however, poorer outcome for metastatic RMS was most related to clinical risk factors including age, primary site, and number of metastatic sites.

CONCLUSIONS

In contrast to low- or intermediate-risk RMS, in metastatic RMS, clinical risk factors have the most impact on patient outcome. PAX-FOXO1 fusion is more common in patients with a high Oberlin score, but fusion status is not an independent biomarker of prognosis.

Morphological analysis of interbody fusion following posterior lumbar interbody fusion with cages using computed tomography

Posterior lumbar interbody fusion (PLIF) using cages in conjunction with pedicle screw fixation is considered the gold standard for surgical treatment of degenerative lumbar spine disorders due to its biomechanical stability and high fusion rate. However, research regarding patterns of fusion in the interbody space during the early postoperative period is lacking.Sixty consecutive patients were recruited from May 2013 to June 2015. All patients underwent PLIF using 2 titanium cages filled with local bone chips from decompressed lamina and facet bone in conjunction with pedicle screw fixation. Computed tomography scans were obtained 3 to 6 months following surgery in order to evaluate the partial fusion state. Computed tomography (CT) classification of fusion morphology was divided into 8 groups and then into compartments according to fusion space, and the rate of fusion for each was calculated. Further follow-up was conducted to confirm fusion state and assess outcomes.The most frequent pattern of interbody fusion was bilateral intra-cage fusion with unilateral lateral bridging of extra-cage areas (N = 36, 43.4%); the least frequent was interspace bridging of the 2 cages alone (N = 0, 0%). The fusion rate for the intra-cage area (Compartment 1) reached 100%. However, the fusion in the lateral space outside of cages (Compartment 2) was not satisfactory, though reasonable (72.3%). All patients were confirmed as achieving adequate fusion at the final follow-up, with improved clinical outcomes.Widening of the contact area between the vertebral body and cages is recommended to promote increased interbody fusion during the early postoperative period.

Second malignancy risk among pediatric, adolescent, and young adult survivors of fusion-positive and fusion-negative sarcomas: Results from the SEER database, 1992 through 2012

BACKGROUND

The current study builds on the hypothesis that cancer-predisposing germline mutations are less common among patients with fusion-positive (F+) sarcomas compared to those with fusion-negative (F-) sarcomas, resulting in a lower risk of developing second malignant neoplasms (SMNs) in those with F + sarcomas.

METHODS

Standardized incidence ratios (SIRs) for developing SMNs were evaluated in 4822 survivors of F + and 3963 survivors of F- sarcomas that were diagnosed between 1992 and 2012 in pediatric, adolescent, and young adult patients (aged birth-39 years) and reported in the Surveillance, Epidemiology, and End Results (SEER) database. Cox proportional hazards models (adjusted hazard ratio [aHR]) and competing risk methods (subhazard ratio [sHR]) were used to evaluate SMN risk in those with F- versus F + sarcomas while controlling for demographic and clinical variables.

RESULTS

SMN risk was found to be nearly 2-fold greater among survivors of F + sarcomas (SIR, 1.86; 95% confidence interval [95% CI], 1.48-2.30) and nearly 3-fold greater among survivors of F- sarcomas (SIR, 2.89; 95% CI, 2.30-3.59) compared with the reference population. Although SMN types were noted to be similar between the fusion groups, the rate of any SMN was noted to be greater among survivors of F- sarcomas (aHR, 1.38 [95% CI, 1.01-1.89] and sHR, 1.27 [95% CI, 0.94-1.73]) when compared with survivors of F + sarcomas. The difference was most notable for solid tumor SMNs after index sarcomas were diagnosed between 2002 and 2012, for which rates of SMN were >2-fold greater among survivors of F- sarcomas (aHR, 2.31 [95% CI, 1.20-4.48] and sHR, 2.24 [95% CI, 1.13-4.43]).

CONCLUSIONS

The findings of the current study highlight the increased SMN risk experienced by survivors of sarcoma and demonstrate higher SMN rates in survivors of F- sarcomas compared to those with a history of F + sarcomas. Cancer 2016;122:3492-3500. © 2016 American Cancer Society.

Histology, Fusion Status, and Outcome in Alveolar Rhabdomyosarcoma With Low-Risk Clinical Features: A Report From the Children's Oncology Group

BACKGROUND

Distinguishing alveolar rhabdomyosarcoma (ARMS) from embryonal rhabdomyosarcoma (ERMS) is of prognostic and therapeutic importance. Criteria for classifying these entities evolved significantly from 1995 to 2013. ARMS is associated with inferior outcome; therefore, patients with alveolar histology have generally been excluded from low-risk therapy. However, patients with ARMS and low-risk stage and group (Stage 1, Group I/II/orbit III; or Stage 2/3, Group I/II) were eligible for the Children's Oncology Group (COG) low-risk rhabdomyosarcoma (RMS) study D9602 from 1997 to 1999. The characteristics and outcomes of these patients have not been previously reported, and the histology of these cases has not been reviewed using current criteria.

PROCEDURE

We re-reviewed cases that were classified as ARMS on D9602 using current histologic criteria, determined PAX3/PAX7-FOXO1 fusion status, and compared these data with outcome for this unique group of patients.

RESULTS

Thirty-eight patients with ARMS were enrolled onto D9602. Only one-third of cases with slides available for re-review (11/33) remained classified as ARMS by current histologic criteria. Most cases were reclassified as ERMS (17/33, 51.5%). Cases that remained classified as ARMS were typically fusion-positive (8/11, 73%), therefore current classification results in a similar rate of fusion-positive ARMS for all clinical risk groups. In conjunction with data from COG intermediate-risk treatment protocol D9803, our data demonstrate excellent outcomes for fusion-negative ARMS with otherwise low-risk clinical features.

CONCLUSIONS

Patients with fusion-positive RMS with low-risk clinical features should be classified and treated as intermediate risk, while patients with fusion-negative ARMS could be appropriately treated with reduced intensity therapy.

Lifestyle-Related Diseases Affect Surgical Outcomes after Posterior Lumbar Interbody Fusion

Study Design Retrospective study. Objective Hyperlipidemia (HL) and hypertension (HT) lead to systemic atherosclerosis. Not only atherosclerosis but also bone fragility and/or low bone mineral density result from diabetes mellitus (DM) and chronic kidney disease (CKD). The purpose of this study was to examine whether these lifestyle-related diseases affected surgical outcomes after posterior lumbar interbody fusion (PLIF). Methods The subjects comprised 122 consecutive patients who underwent single-level PLIF for degenerative lumbar spinal disorders. The clinical results were assessed using the Japanese Orthopaedic Association (JOA) score before surgery and at 2 years postoperatively. The fusion status was graded as union in situ, collapsed union, or nonunion at 2 years after surgery. The abdominal aorta calcification (AAC) score was assessed using preoperative lateral radiographs of the lumbar spine. Results HL did not significantly affect the JOA score recovery rate. On the other hand, HT and CKD (stage 3 to 4) had a significant adverse effect on the recovery rate. The recovery rate was also lower in the DM group than in the non-DM group, but the difference was not significant. The AAC score was negatively correlated with the JOA score recovery rate. The fusion status was not significantly affected by HL, HT, DM, or CKD; however, the AAC score was significantly higher in the collapsed union and nonunion group than in the union in situ group. Conclusions At 2 years after PLIF, the presence of HT, CKD, and AAC was associated with significantly worse clinical outcomes, and advanced AAC significantly affected fusion status.