Local Failure in Parameningeal Rhabdomyosarcoma: Does Response to Induction Chemotherapy Matter?

Abstract

year EFS for localized and metastatic patients are 81% and 29% (p 8 cm), 95% vs 77%. General toxicities are shown in the table. In 31 patients with head and neck disease sites the CI of cataract is 35% at 5 years and is highly correlated with orbital disease site (100% vs 21%, p < 0.01) and dose to the lens (p < 0.01). Tumor size at diagnosis correlates with reduced mandibular ROM (p Z 0.04), while site does not (fav/unfav, p Z 0.15). In 14 patients with extremity disease sites, the CI of fracture is 17%, with an average max dose to bone of 46.8 Gy for all 14 patients. In a proportional hazard model, increasing age correlates with physis closure (p Z 0.01), while mean physis dose approaches, but is not significant (p Z 0.13). Growth rate of the bone is reduced by increasing age at RT (p < 0.01), while the impact of mean physis dose approaches significance (p Z 0.10). In 14 patients with pelvic disease 5/14 experienced at least one episode of 3+ hematuria within the first year of RT. Nine of 14 had a measurable degree of hematuria during that year. Ten of 14 had some degree of bladder wall thickening post RT on imaging. No patient required permanent urinary diversion. Conclusions: Modern 3DCRT/IMRT with specific targeting guidelines yields excellent local control for most children with RMS. Despite the use of modern RT and limited target volumes, measurable toxicities are evident and can be correlated with age and RT dose. Techniques and targeting paradigms that further reduce normal tissue exposures are needed. Author Disclosure: M. Krasin: E. Research Grant; Lance Armstrong Foundation Survivorship Grant 2005-2007. C. Hua: None. L.E. Kun: None. A. Pappo: None. A. Pai Panandiker: None. M. Brown: None. A. Davidoff: None. B. Shulkin: None. B. McCarville: None. T.E. Merchant: None.