Micrognathia after radiation therapy for childhood facial tumors. Report of two cases with long-term follow-up

A Long-Term Follow-Up of Dental and Craniofacial Disturbances after Cancer Therapy in a Pediatric Rhabdomyosarcoma Patient: Case Report

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in children and adolescents. A boy aged seven years and five months was diagnosed with stage three group III embryonal parameningeal RMS with intracranial extension. He received chemotherapy for 23 weeks in combination with localized radiotherapy during the inductive phase of nine weeks (a total tumor dose of 5040 cGy). Three months later, he was referred to the department of pediatric dentistry for radiation-induced caries, the treatment of which was later terminated because of severe trismus and radiation-induced oropharyngeal mucositis. Three years later, the patient returned for the fitting of a prosthesis because of mastication problems. The dental treatments performed included: extraction, banding, composite resin restorations, root canal fillings, and stainless steel crown fabrication. An interim denture was fitted due to the poor retention of the fixed prosthesis. As the patient grew older, they developed facial asymmetry as a result of the prominent atrophy of their right cheek. By the age of 32, they had lost multiple teeth and exhibited severe facial deformity. Therefore, it is essential not only to involve a multidisciplinary medical team before, during, and after cancer therapy, but also to initiate long-term follow-ups given the potential effects of late sequelae after chemoradiation in multiple developmental areas.

Local Irradiation of Mouse Tooth Germ Gives Insight into the Direct Effects of Irradiation on Root Development

To elucidate the mechanism underlying the failure of root formation after irradiation, we established a method of local irradiation of the molar tooth germ and demonstrated that radiation directly affected dental root development. In the current study, to locally irradiate the lower first molars of 5-day-old C57BL/6J mice, we used lead glass containing a hole as a collimator. We confirmed that our local irradiation method targeted only the tooth germ. The irradiated root was immature in terms of apical growth, and dentin formation was irregular along the outside of the root apices. Moreover, calcified tissue apically surrounded Hertwig's epithelial root sheath, which disappeared abnormally early. This method using a local irradiation experimental model will facilitate research into radiation-induced disorders of dental root formation.

Dental and craniofacial alterations in long-term survivors of childhood head and neck rhabdomyosarcoma

OBJECTIVE

Rhabdomyosarcoma (RMS) represents the most common soft tissue sarcoma that affects children. Treatment involves chemoradiotherapy. This study aimed at evaluating the long-term alterations to teeth and cranial bones in children, teenagers, and young adults after oncologic treatment.

STUDY DESIGN

We conducted a cross-sectional study of patients undergoing treatment for head and neck RMS between 1988 and 2011. We evaluated demographic, clinical, and treatment data and performed panoramic radiography, cephalometry, and photography.

RESULTS

We evaluated 27 long-term survivors, most of whom had been treated between ages 0 to 5 years (51.9%). The total radiation dose applied was 50.4 Gy, and the chemotherapy combination included vincristine, actinomycin D, and cyclophosphamide in 51.9% of the cases. We observed 603 dental alterations, among which 377 (62.7%) occurred in patients ages 0 to 5 years, and root shortening was the most frequent alteration observed (24.2%). With regard to facial bones, 74% of the patients had some level of facial asymmetry, 70.4% had reduced facial depth, 48.4% had mandibles of short size, and 77.8% had reduced facial height.

CONCLUSIONS

Children submitted to RMS treatment involving chemotherapy and radiotherapy displayed significant dental and craniofacial alterations, especially when treatment occurred between ages 0 and 5 years.

Pediatric Microvascular Reconstruction: A Report from the Microvascular Committee

BACKGROUND: Free tissue transfer is an integral part of modern head and neck surgery in the adult population. Its use in the pediatric population has not been well described. Recently, there has been an increase in the application of these techniques in the pediatric population. The morbidity of free tissue transfer in small pediatric patients and its effect on growth has not been well described.

OBJECTIVE: To evaluate the utility of microvascular reconstruction techniques in the pediatric population.

STUDY DESIGN: A consensus study was performed by the microvascular committee of the American Academy of Otolaryngology-Head and Neck Surgery. Thirty active microvascular surgeons reviewed their databases to find patients less than 21 years of age who underwent free tissue transfer.

RESULTS: 49 free tissue transfers performed between 1999 and 2005. The mean age was 12.1 years (age range, 3–21). The types of flaps transferred were radial forearm (10), fibula (21), rectus abdominus (7), scapula (1), latissimus dorsi (3), groin (1), gracillus (4), and jejunum (2). Morbidity at the donor site was relatively minimal. Five patients developed wound breakdown. One of these required return to the operating room. Morbidity at the reconstructed site was also rare. Patients were followed for an average of 49 months (range, 1–131 months), and no problems were noted with growth at the donor or recipient sites.

CONCLUSIONS: Free flaps in the pediatric population have morbidity and survival similar to those in the adult population.

SIGNIFICANCE: While indications differ from those in the adult population, these techniques are viable and valuable and should be considered in the pediatric reconstructive paradigm.

Long term chemoradiotherapy-related dental and skeletal complications in a young female with nasopharyngeal carcinoma

We describe the long-term complications six years after chemoradiotherapy in a 20-year old woman with nasopharyngeal carcinoma. We wanted to know whether the radiation dose was constant throughout the oral cavity, and thus uniformly affecting the corresponding dental and skeletal structures. Clinical and radiologic findings are described six years after chemoradiotherapy based on a two-dimensional computerized treatment planning system. This revealed radiation caries limited only to posterior teeth, proximal caries in the anterior teeth, limited but continuous salivary flow, mild periodontal infection, mild xerostomia, and a regenerative capacity of bones and the developmental process. The quantitative assessment of radiation delivered to the mandible revealed a high radiation dose in the posterior area and a minimal dose in the anterior area. This explains the differences in caries manifestation between the anterior and posterior teeth. According to the present study, individualized radiation fields, using a two-dimensional treatment planning system, result in restriction of severe damage of the dental and skeletal structures, which usually follows chemoradiotherapy. Orthodontic treatment could be initiated according to individual patient needs.

Impact of radiation and chemotherapy on risk of dental abnormalities: a report from the Childhood Cancer Survivor Study

BACKGROUND

The current study was performed to describe frequencies and risk factors of altered oral health and odontogenesis in childhood cancer survivors.

METHODS

In total, 9308 survivors who were diagnosed between 1970 and 1986 and 2951 siblings from the Childhood Cancer Survivor Study completed a survey that contained oral-dental health information. The authors analyzed treatment impact, socioeconomic data, and patient demographics on dental outcomes using univariate and multivariate logistic regression models to estimate odds ratios (ORs).

RESULTS

In multivariate analysis, survivors were more likely to report microdontia (OR, 3.0; 95% confidence interval [95% CI], 2.4-3.8), hypodontia (OR, 1.7; 95% CI, 1.4-2.0), root abnormalities (OR, 3.0; 95% CI, 2.2-4.0), abnormal enamel (OR, 2.4; 95% CI, 2.0-2.9), teeth loss>or=6 (OR, 2.6; 95% CI, 1.9-3.6), severe gingivitis (OR, 1.2; 95% CI, 1.0-1.5), and xerostomia (OR, 9.7; 95% CI, 4.8-19.7). Controlling for chemotherapy and socioeconomic factors, radiation exposure of >or=20 Gray to dentition was associated significantly with an increased risk of >or=1 dental abnormality. Dose-dependent alkylating agent therapy significantly increased the risk of >or=1 anatomic/developmental dental abnormalities in survivors who were diagnosed at age<5 years (OR, 1.7, 2.7, and 3.3 for alkylating agent scores of 1, 2, and 3, respectively).

CONCLUSIONS

Radiation and chemotherapy were independent risk factors for adverse oral-dental sequelae among childhood cancer survivors. The authors concluded that patients who received receiving alkylating agents at age<5 years should be closely monitored.

Effects of therapy on dentofacial development in long-term survivors of head and neck rhabdomyosarcoma: the memorial sloan-kettering cancer center experience

PURPOSE

To describe potential effects of multimodality therapy on dental and facial development in long-term survivors of head and neck rhabdomyosarcoma.

PATIENTS AND METHODS

The medical records of all patients aged 20 years or less presenting between 1985 and 1996 with a diagnosis of rhabdomyosarcoma and treated by protocol were reviewed. Head and neck rhabdomyosarcoma patients who were followed in the Dental Service and were alive and free of disease with at least a 5-year follow-up were included in the review. Ten patients satisfied the inclusion criteria and form the basis of this report. The median age at diagnosis of the 10 patients was 4.3 years (range 10 months to 19.5 years). All patients were treated with chemotherapy, two patients underwent surgery, and all but one patient received external beam radiation therapy.

RESULTS

Clinical or radiographic dentofacial abnormalities were observed in 8 of the 10 (80%) patients. Abnormalities included enamel defects, bony hypoplasia/facial asymmetry, trismus, velopharyngeal incompetency, tooth/root agenesis, and disturbance in root development. Bony hypoplasia and disturbance in root formation were the most common findings.

CONCLUSIONS

Multimodality therapy for head and neck rhabdomyosarcoma can result in dentofacial abnormalities that affect the patient's quality of life. The care of the long-term survivor requires a multidisciplinary approach, including early involvement of the dental team.

Dento-maxillofacial sequelae in a child treated for a rhabdomyosarcoma in the head and neck. A case report

This case report describes severe dento-maxillofacial defects after chemoradiation therapy in a child aged 9 years 6 months with a parameningeal rhabdomyosarcoma. A clinical and radiologic (apical dental radiographs, orthopantograph, lateral skull roentgenogram) dental follow-up over 4 years showed such dental abnormalities as root blunting, mild to severe root shortening, premature closure of the root apices, and severe radiation caries. Craniofacial morphology evaluated by cephalometric analysis and dental models showed deficiency with mandibular and maxillary hypoplasia.

Dental abnormalities in children treated for neuroblastoma

PURPOSE

To determine the frequency and types of dental abnormalities among children treated at a young age for cancer, as represented by neuroblastoma.

PATIENTS AND METHODS

We retrospectively reviewed the dental records and panoramic radiographs of 542 children who were treated for neuroblastoma at our institution over a 31-year period. Patients in our study had to meet the following criteria: they were treated on an institutional protocol, they had undergone panoramic radiography, and their dental follow-up continued for at least 2 years after diagnosis. We evaluated the frequency of clinically or radiographically apparent microdontia, excessive caries, root stunting, hypodontia, and enamel hypoplasia in our study population.

RESULTS

Of the 52 patients who met the study criteria, 71% developed dental abnormalities, comprising microdontia in 38%, excessive caries in 29%, root stunting in 17%, hypodontia in 17%, and enamel hypoplasia in 17%. In nearly half (23) of our patients, neuroblastoma was diagnosed on or before their first birthday.

CONCLUSION

Children treated for neuroblastoma are at high risk for abnormal dental development. The abnormalities in these patients may require extensive dental care and can compromise their quality of life. Frequent dental examinations and an intense oral hygiene program before, during, and after treatment may improve overall dental health.