**4. Treatment of pediatric jaw tumors**

**•** Fine needle aspiration for cytologic study is useful in salivary gland and thyroid gland lesions. However, its generalized use for all pediatric head and neck masses is limited due

**•** Large bore needle biopsy has no established role in the evaluation of head and neck malignancies in children and has been reported to cause seeding along the needle tract in

OTs have a specific histological structure reflecting various stages of odontogenesis and are located mainly in the jaws, rarely in other parts of the skeletal system. Due to their specific structure and location they have been identified and classified by pathologists into a separate group of neoplasms differing from other lesions developing in the oral cavity and facial bones [17]. Odontogenic tissue is programmed to produce dentin and enamel due to active interac‐ tions between odontogenic mesenchyme and epithelium. Tooth formation is achieved via odontogenic mesenchyme and epithelium stage- and spatial-specific differentiation from early tooth development to late maturation [18]. Therefore, when odontogenic tissue becomes undifferentiated and undergoes tumoral changes, it has the potential to produce abnormal calcifications with enameloid, dentinoid, and cementum-like material histologic features. For this reason, these odontogenic calcifications are important odontogenic tumor characteristics and occasionally are accompanied by odontogenic epithelium ghost cell change and amor‐

Aspiration cytology, a well established diagnostic tool in adult oncology, is recently gaining acceptance in pediatric population, as clinicians add this technique to their diagnostic arma‐ mentarium. Fine-needle aspiration cytology is a useful and reliable tool in the diagnosis of head and neck OTs with no contraindications and minimal complications even in children [20]. More than 95% of all OT reported in large series are benign and around 75% are represented by odontomas, ameloblastomas and myxomas (which could be considered as "relatively frequent OT"). Due to the inclusion of the odontogenic keratocyst as a tumor, these figures will be modified significantly, as this lesion is more frequently diagnosed than the other three entities. Some studies have shown epidemiological data that demonstrate that there is a second group of OT, which, although rare in terms of general pathology, are of "intermediate frequency" with respect to other OT, which have to be considered in the differential diagnosis of tumors of the oral and maxillofacial regions; therefore they have to be included within the contents of pathology of the graduate and post-graduate courses of oral and general pathology. The lack of specific markers to confirm the odontogenic origin of all the lesions included in the current WHO classification makes diagnoses mainly on anatomic considerations, or on the histomorphological similarities among some tumors with the above mentioned odontogenic structures. However, as most OT contain variable amounts of epithelium, and the fact that such tissue may express several of the more than 20 cytokeratin markers (intermediate filaments of the epithelial cells) known to date, there are some studies that have demonstrated that cytokeratins 14 and 19 are the more frequently expressed by OT, and that these are also expressed in the different epithelial structures of the developing tooth [21, 22], leading to promote their use as a diagnostic tool to support the odontogenic nature of these entities. Additionally, the expression of amelogenin, a representative protein of the enamel matrix,

to the rarity of squamous or glandular neoplasms developing in children

phous odontogenic mesenchyme hyalinization [19].

282 A Textbook of Advanced Oral and Maxillofacial Surgery Volume 2

children. [9, 16]

The majority of tumors of the mouth and jaw in children are benign. Tanaka et al. reported that only 3% of their cases were malignant in nature. In another study, benign tumors composed 93% of the cases (13, 14, 27).

Treatment consists of a range of surgical methods, from surgical curettage to hemimandibu‐ lectomy and reconstruction with bone graft. Generally, surgical excision, curettage, cryosur‐ gery or en bloc resection are adequate for treatment of these tumors. However, some patients need multiple treatment because of its specific criterias such as the clinical behavior and extent of the lesion. Odontogenic lesions encompasses a wide spectrum of lesions and their variants, which either can be a cyst or a tumor. Odontogenic cysts are derived from the epithelium associated with the development of the dental apparatus while a tumor forms through some aberration from the normal pattern of odontogenesis. But the fact, that these lesions can mimic each other can complicate the diagnosis. The Adenomatoid Odontogenic Tumor is a benign, nonaggressive odontogenic tumor which has been known by a number of descriptive names since it was first reported. In almost all instances, the lesion may be removed by surgical enucleation. Unicystic Ameloblastoma is another tumor of the odontogenic series which has been described as benign but locally invasive. The Dentigerous Cyst, a cyst of odontogenic origin, has the potential of transforming into an Ameloblastoma. The Odontogenic Keratocyst, is characterized by aggressive behavior has debatable treatment options. All OTs can have a similar clinical and radiographic features which can mislead the dentist and a biopsy is needed to make a final diagnosis. Of all odontogenic tumors, ameloblastomas are the most controver‐ sial in terms of treatment. Treatments range from surgical curettage to bloc excision or resection [28]. Surgical excision in the infant or child is sometimes met with resistance by both parents and physicians, yet with many tumors surgery is clearly the best treatment. A wide resection for some tumors may pose psychological and cosmetic difficulties that parents can learn to accept if these difficulties are discussed in an open and helpful manner. When parents accept their children disabilities, the children in turn, can adjust very well functionally and psycho‐ logically following operations [29]. Cryosurgery is relatively new to the management of head and neck tumors in children. Local freezing has the ability to destroy tumor cells. A wide variety of probe tips are available to treat lesions of the skin, nose, mouth, nasopharynx, oropharynx, hypopharynx and larynx. Unlike surgical excision or radiation therapy, cryosur‐ gery has the capability of destroying the tumor and only minimally affecting the surrounding normal tissue; also unlike radiation therapy,cryosurgery can be repeatedly administered to a specific area should the tumor persist or recur. The role of cryosurgery is still being assessed, but the potential is both great and exciting [29]. In planning treatment for pediatric tumors, authors stress the importance of the growth development of the jaw, and of esthetics and functional concerns in later periods of life [30].
