Long-term effect of chemotherapy-intensity-modulated radiation therapy (chemo-IMRT) on dentofacial development in head and neck rhabdomyosarcoma patients.

Dentofacial developmental abnormalities have been reported in head and neck rhabdomyosarcoma (HNRMS) patients treated with conventional radiotherapy technique and chemotherapy. This current study investigates dentofacial long-term effects among HNRMS survivors managed with intensity-modulated radiotherapy (IMRT) and chemotherapy. In general, IMRT is a more effective 3D-conformal radiotherapy technique, which delivers high doses of radiation to the tumor target while minimizing doses received by the surrounding normal tissues. The medical records and radiographs of thirteen patients were reviewed to identify the following: 1. Facial asymmetry and jaw hypoplasia. 2. Effects on the dental tissue causing tooth agenesis/hypodontia, root agenesis/stunting/malformation, and/or enamel hypoplasia. 3. Trismus, hyposalivation/xerostomia. Seven patients presented with facial asymmetry and jaw hypoplasia, 9 patients presented with effects on the dental tissue [root agenesis/stunting/malformation (9), tooth agenesis/hypodontia (7) and enamel hypoplasia (3)] and 7 patients developed trismus and /or xerostomia. All patients with facial asymmetry and jaw hypoplasia also developed dental abnormalities. Patients with dentofacial developmental abnormalities were ≤7 years of age at treatment. Our study shows that dentofacial developmental abnormalities are still a burden in the era of IMRT and as prognosis of childhood malignancy improves and more patients survive, these late dentofacial sequelae among childhood cancer survivors will become more common. Dental oncologists should be integral members in the management of children with head and neck cancers.