Age-based disparities in treatment and outcomes of retroperitoneal rhabdomyosarcoma

Characteristics and prognosis of embryonal rhabdomyosarcoma in children and adolescents: An analysis of 464 cases from the SEER database

IMPORTANCE

As the most common subtype of pediatric rhabdomyosarcoma (RMS), the prognosis of embryonal RMS has rarely been investigated solely.

OBJECTIVE

To perform a population-based study to characterize the prognosis of embryonal RMS in children and adolescents.

METHODS

Demographic and clinical features were retrospectively evaluated in selected patients with embryonal RMS registered in the Surveillance, Epidemiology, and End Results (SEER) program from 1988 to 2016. Survival curves were compared using the log-rank test. A multivariate Cox proportional hazards model was developed to assess the impact of each factor on the overall survival. A nomogram was constructed based on the results of Cox regression model.

RESULTS

A total of 464 patients were included in the analysis, among which 64.6% were male and 70.2% were white patients. About 38.6% and 26.3% of the patients were at 1-4 years and 5-9 years, respectively. Cox analysis showed that patients at age group 5-9 years had the lowest risk of mortality (hazard ratio [HR], 0.277; 95% confidential interval [CI], 0.123-0.620), compared with patients diagnosed at less than 1-year-old, and age group 1-4 years had the second-best prognosis. Patients having distant tumors had significantly higher mortality risk (HR, 4.842; 95% CI, 2.804-8.362) than the patients with localized tumor. Compared with receiving no surgery or radiotherapy, receiving any combination of surgery and radiotherapy would lower the risk of mortality significantly (for surgery without radiotherapy: HR, 0.418; for radiotherapy without surgery: HR, 0.405; and for surgery plus radiotherapy: HR, 0.410).

INTERPRETATION

Age, stage at diagnosis, and treatment received were found to be the most important predictors of the overall survival of pediatric embryonal RMS.

A systematic review of population-based studies examining outcomes in primary retroperitoneal sarcoma surgery

Retroperitoneal sarcomas (RPS) are rare mesenchymal tumours. Their rarity challenges our ability to understand expected outcomes. The aim of this systematic review was to examine 30-day morbidity and mortality, overall survival rates and prognostic predictors from population-based studies for patients undergoing curative resection for primary RPS. A systematic literature review of EMBASE, MEDLINE, PUBMED and the Cochrane library was performed using PRISMA for population-based studies reporting from nationally registered databases on primary RPS surgical resections in adults. The main outcomes evaluated were 30-day morbidity and mortality and overall survival rates. The use of additional treatment modalities and predictors of overall survival were also examined. Fourteen studies (n = 12 834 patients) reporting from 3 national databases, (Surveillance, Epidemiology and End Results (SEER), the United States National Cancer Database (US NCDB) and the American College of Surgeons' National Surgical Quality Improvement Program (ACS NSQIP)) were analysed. The reported overall 30-day morbidity and mortality were 23% (n = 191/846) and 3% (n = 278/10 181) respectively. Reported use of perioperative radiotherapy was 28%. No study reported loco-regional recurrence rates. Overall reported 5-year survival ranged from 52% to 62%. Independent predictors of overall survival were age of the patient, resection margin, tumour grade and size, histological subtype and receipt of radiotherapy. This review of population-based data demonstrated relatively low 30-day morbidity rates in patients undergoing curative surgical resections for primary RPS. Thirty-day mortality rates were similar to other abdominal tumour groups. There remains a paucity of data reporting recurrence rates, however 5-year survival rates ranged from 52 to 62%.