Sinonasal Rhabdomyosarcoma: A 26-Year Experience at a Single Institution

Sinonasal rhabdomyosarcoma (SNRMS) is an aggressive malignancy originating from embryonic mesenchymal tissue. It is the most common soft tissue tumor in children and rarely occurs in adults. As few retrospective studies have been conducted in patients with SNRMS, the purpose of this study was to present our twenty-six-year institutional experience at a tertiary care academic medical center to examine prognostic factors that were associated with outcomes in this population.

A cross-sectional retrospective case series was performed in patients who were diagnosed with SNRMS between 1994 and 2020. Data were extracted from the electronic medical record. Outcomes included overall survival (OS) time, locoregional recurrence free (LRF) time, and distant metastases free (DMF) time. Bivariate associations were tested by Chi-square or Wilcoxon rank-sum test. Survival and recurrence free proportions were estimated by the Kaplan–Meier method. Cox proportional hazard models were used to test associations between predictors and time to recurrences and death.

In total, 12 females and 17 males were included in the study; the median age was 26 (range, 3–66), with the majority over the age of 18 (n = 17, 59%). 19 (66%) were white and 9 (31%) were black. The pathology of the tumors for 21 (72%) cases were alveolar and 5 (17%) were embryonal and were primarily located in the ethmoids (n = 10, 34%), nasal cavity (n = 10, 34%), maxillary sinus (n = 4, 14%), sphenoid sinus (n = 1, 3%), nasolacrimal duct (n = 2, 7%), nasopharynx (n = 1, 3%), and PPF (n = 1, 3%). When examining the IRS COG risk group, the majority were intermediate (n = 20; 69%), followed by high (n = 6, 21%) and low (n = 2, 7%).

Kaplan–Meier estimates at 2 years for OS, LRF, and DMF were 45, 40, and 47%, respectively, and 28, 32, and 27%, at 5 years. Patients with a primary tumor located in the ethmoids compared to the nasal cavity had worse OS time (HR: 4.20; 95% CI: 1.41–12.55; p = 0.01), and free DMF time (HR: 3.13; 95% CI: 1.06–9.26; p = 0.04), and patients with a primary tumor in the ethmoids versus other tumor locations similarly had worse OS time (HR: 8.13; 95% CI: 2.07–32; p = 0.003) and free DMF time (HR: 4.66; 95% CI: 1.21–17.95; p = 0.03). Patients with an overall stage of 4 versus 3 similarly had worse OS time (HR: 6.53; 95% CI: 20.02–21.08; p = 0.0002) and free DMF time (HR: 6.86; 95% CI: 2.02–23.32; p = 0.002). Patients with an IRS COG risk group of 3 versus 2 had worse OS time (HR: 6.83; 95% CI: 2.17–21.50; p = 0.001) and free DMF time (HR: 4.95; 95% CI: 1.60–15.31; p = 0.006). Patients with an IRS COG risk group of 4 versus 2 after treatment had worse OS time (HR: 6.16; 95% CI: 1.60–23.72, p = 0.008) and free DMF time (HR: 1.73; 95% CI: 1.73–40.13, p = 0.008).

Survival for sinonasal rhabdomyosarcoma remains poor. Tumor location, staging, and IRS COG Risk groups were associated with worse survival times and are thus important considerations in prognosis for SNRMS.

Publication History

Article published online:
12 February 2021