Clinicopathological Characteristics, Survival Outcomes, and Prognostic Factors in Adult Patients With Sinonasal Rhabdomyosarcoma: Insights from a Retrospective Cohort Study

Background/Aim: Rhabdomyosarcoma (RMS) is a rare tumor with distinct morphological types and challenging diagnosis. This study aimed to investigate clinicopathological characteristics, survival outcomes, and factors influencing prognosis in adult patients with sinonasal RMS, addressing a critical gap in knowledge. Patients and Methods: This retrospective cohort study employed various statistical analyses to investigate patients with RMS. Descriptive statistics summarized demographic and clinical characteristics, while survival analysis using the Kaplan-Meier method and Cox proportional hazards model explored the relationship between covariates and survival outcomes. Results: We analyzed 13 cases (7 males, 6 females) of sinonasal RMS. The average age at onset was 42.5 years (standard deviation 18.9). Tumors were observed in multiple locations, predominantly in the maxillary sinus (n=7), followed by the ethmoid sinus (n=5), and the sphenoid sinus (n=1). The study revealed a low survival rate, with 12 patients succumbing to the disease and only one patient surviving. Over time, survival probabilities declined from 92.31% (at 0.5 months) to 7.69% (at 45 months). The analysis indicated a borderline statistically significant positive association between age at diagnosis below 40 years and survival (p=0.05). Sex was found to be significantly associated with survival (p=0.03), with male patients exhibiting a higher survival rate (hazard ratio=0.08, 95%CI=0.01-0.81). Conclusion: This study highlights the complex nature of sinonasal RMS in adults. The low survival rate and distinct tumor locations emphasize the need for further research to improve diagnosis and treatment outcomes.