Vet. World, 2012, Vol.5(9):565-567 CLINICAL Maxillofacial rhabdomyosarcoma in the canine maxillofacial area

Juvenile rhabdomyosarcomas were diagnosed in two young dogs based on the results of histopathology, phosphotungstic acid-hematoxylin stain, immunohistochemistry, and the age of the dogs. One dog, an 2yrs germanshepard had tumor mass in the maxillary premolar teeth gingiva . Histologically, the gingival mass was an alveolar type of rhabdomyosarcoma . The other dog, a 1.5-year-old Basset Hound, had alveolar type of rhabdomyosarcoma involving the premolar to molar teeth region and CT examination in each case revealed extensive bony involvement of maxilla .temporal muscles, with metastasis to the regional lymph node and lungs. A diagnosis of solid-pattern alveolar rhabdomyosarcoma was made on the basis of morphologic and immunohistochemical staining for desmin. Alveolar rhabdomyosarcoma should be considered in the differential diagnosis of tumors in juvenile dogs, especially when cytologic findings reveal round, undifferentiated cells. Both the cases were subjected to surgical excision of tumor tissue followed by chemotherapy. Both the dogs died within two months of the admission.


Introduction
revealed a firm, 2.5 x 2cm ulcerated, protruding mass in the gingiva of the left maxilla at the level of the Rhabdomyosarcomas spontaneously arising in upper first premolar to first molar.A wedge biopsy sample skeletal muscles are rare in domestic animals [1] .In was submitted for histopathological examination.humans, rhabdomyosarcoma is the most common soft Dog No.2 was a 3 yr old male Boxer with a 1tissue tumor in infants and children under 15 years of month history of progressive left Swelling in the left age, comprising about 50% of all childhood soft tissue maxillary molar teeth gingiva .Physical examination neoplasm [2,3].Rhabdomyosarcomas are classified revealed a firm,1.5 x 2cm diameter swelling and firm into three main types based on the histological enlargement of a left submandibular lymphnode was features: pleomorphic, embryonal and alveolar [1].
noted.In the CT examination, a large mass and defect Domestic animals with Rhabdomyosarcomas have a in the maxilla was observed.A biopsy of the leasion broad age range with a mean age of 2-3 years [1,4,5].
was performed Cytology revealed an atypical population There is no clear pattern of site prevalence.
of round cells of undetermined origin.A diagnosis of Rhabdomyosarcomas can also be termed as alveolar rhabdomyosarcoma was reached via histopa-"Botryoid" because of their appearance of grape Like thology and confirmed with positive immunohistoappearance.In this report, we describe juvenile chemical staining for desmin.Cytological examination Rhabdomyosarcomas in two young dogs an 2yrs of the submandibular lymphnode suggested tumor germanshepard had tumor mass in the left maxillary invasion.The tissue samples from both dogs were premolar teeth gingiva .Histologically the gingival fixed in 10% phosphate-buffered formalin and processed mass was an alveolar type of rhabdomyosarcoma.At routinely for light microscopic examination.Replicate the follow-up examination 2 weeks later, the owner sections of the tumors were also stained with described a left maxillary swelling that had been rapidly phosphotungstic acid-hematoxylin and periodic acidgrowing for the last 3 days.Physical examination Schiff methods and used for immunohistochemical mucosa, maxillary alveolar ridge, and hard palate were identification of desmin, skeletal muscle actin, and all involved.The soft tissue was more damaged than cytokeratin (AB 1 /AE3).Histologically, the gingival the bone, suggesting that the tumor primarily mass of dog No. 1 was a locally invasive neoplasm originated in the buccal mucosa.Only two juvenile with multiple areas of necrosis and haemorrhage.The rhabdomyosarcomas involving the oropharyngeal tissues neoplasm consisted of round to fusiform cells grouped of dogs have been reported previously, and both were into a lobular pattern by prominent fibrous septa.The alveolar types [8,9] .tumor cells had round to ovoid, hyperchromaticto The biological significance of different histologic occasionally vesicular nuclei and small to moderate types of juvenile rhabdomyosarcomas is unknown.In amounts of cytoplasm.Mitotic activity was moderately dogs, the alveolar rhabdomyosarcoma may be more high.The gingival neoplasm had histologic characteristics common than the embryonal type, but larger samples of an alveolar type of rhabdomyo-sarcoma.Based on sizes are needed to determine the relative frequencies the age of both dogs and the histopathology and and biological behavior of different types of this tumor immunochemistry results, the tumors were diagnosed Rhabdomyosarcomas should be considered as a as juvenile rhabdomyosarcomas of different histologic differential diagnosis for tumors in the head and neck types.Immunohistochemical detection of muscle-region of juvenile animals.More number of cases Specific antigens has been valuable for diagnosing need to be studied to evaluate biologic behavior, poorly differentiated rhabdomyosarcomas lacking the incidence, and prevalence of the tumor in animals.In characteristic light microscopic cross-striations or ultra-dogs, sarcomas have been associated with radiation, structural sarcomeric feature [4,6,7].Surgical removal trauma, and parasites (Spirocerca lupi).Most sarcomas of the neoplastic tissue was done.General anesthesia are solitary in the older dog and no definite sex or was maintained by ketamine HCl 10% (Alfamine¨,10 breed predilection is known except for synovial mg/ml, Alfasan) following premedication with sarcomas, in which the ratio of males to females is xylazine 2% (Alfazyne¨, 20 mg/ml, Alfasan).The 3:2.5.Early diagnosis is important because rhabdoregion was prepared for the operation on routine basis.myosarcoma is an aggressive tumor that spreads quickly.The mass was removed through a blunt dissection.Sarcomas tend to have several important common Rifampicine¨ (250 mg) was administered locally.The features in regard to their biologic behavior.They may wound was protected.Parenteral antibiotherapy was arise from any anatomic site in the body.They tend to followed for 5 days postoperatively.
appear as pseudoencapsulated fleshy tumors but have poorly defined histologic margins.Local recurrence is Discussion common after conservative surgical excision.Juvenile rhabdomyosarcomas are the second Sarcomas tend to metastasize through hematomost common malignant head and neck tumors (1 genous methods in up to 25% of cases.Regional 8%), following lymphosarcomas ('l0%), in the human lymph node metastasis is unusual (except for synovial pediatric population About 7 5 % of the human juvenile cell sarcoma).They generally have a poor response to rhabdomyosarcomas are embryonal in type, and the chemotherapy and radiation therapy.Canines soft remaining 20% are the alveolar type [3] .The most tissue sarcomas have also been treated with various common site of involvement in the oral cavity is the treatment forms mainly consisting of surgical and tongue followed by the soft palate, hard palate, and radiation therapy.In this report both the cases were buccal mucosa.In our both the cases the buccal treated surgically, which could reduce tumor volume.swelling of the regional lymphnodes were observed ,at

F i g - 3 .
A p p e a r a n c e o f neoplastic cells, HE, x400.

F i g - 4 .
A p p e a r a n c e o f neoplastic cells 2. Enzinger FM and Weiss SW (1988) Rhabdomyo-Surgery has been considered as main treatment for the sarcoma.In: Soft Tissue Tumors, ed.Stamathis G , 2nd treatment for soft tissue sarcomas.In addition to that ed., pp.448-488.CV Mosby, St. Louis, MO.
immunohi s to chemical analysis.Acta Pathol be regularly followed up.High degree of suspicion,Microbiol Immunol Scand, 96~825-838.earlydiagnosis, and a multidisciplinary treatment 7.Seidal T , Walaas L, Kindblom LG, Angervall L approach would be of great importance in such cases.The initial management of any tumor is critical to a cytologic, light microscopic, electron microscopic, satisfactory outcome of the disease.