Adult head and neck para-meningeal rhabdomyosarcoma: survival outcomes including salvage therapy

Rhabdomyosarcoma at para-meningeal regions of the head and neck has a poor prognosis in children. However, there is insufficient data on its outcomes in adults. We retrospectively examined total 10 patients with adult para-meningeal head and neck rhabdomyosarcoma treated at institutions belonging to the Kyushu Medical Oncology Group. Their characteristics were as follows: median age: 39 years (range 25–63 years), histology (alveolar/spindle): 9/1, and risk group (intermediate/high): 6/4. As a first-line therapy, VAC and ARST0431-based regimen was performed in 9 and 1 patients, respectively. During a first-line therapy, definitive radiation for all lesions were performed in five patients. The median progression-free survival was 11.4 months (95%CI: 5.2–25.8 months): 14.2 months (95%CI: 6.0 – not reached (NR)) for patients with stage I-III and 8.5 months (95%CI: 5.2–25.8 months) for patients with stage IV. Median overall-survival in all patients was 40.8 months (95%CI: 9.1 months–NR): 40.8 months (95%CI: 12.1 – NR) for patients with stage I-III and NR for patients with stage IV. Among seven patients who received salvage therapy, three are still alive, two of whom remain disease-free for over 3 years after completion of the last therapy. Although the prognosis of adult para-meningeal head and neck rhabdomyosarcoma is poor regarding to progression-free survival, some patients experience prolonged survival with salvage therapy.