Juvenile Rhabdomyosarcomas in Two Dogs

Abstract

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 11-month-old Rottweiler, had tumor masses in the maxillary gingiva and the urinary bladder. Histologically, the gingival mass was an alveolar type of rhabdomyosarcoma and the urinary bladder mass was an embryonal type. The other dog, a 1.5-year-old Basset Hound, had an embryonal rhabdomyosarcoma involving the oropharynx and the temporal muscles, with metastasis to the regional lymph node and lungs.

Maxillofacial Rhabdomyosarcoma in the Canine Maxillofacial Area

“…Prognosis of rhabdomyosarcoma in the oral cavity, including the tongue, seemed to be poor. Most of the previous cases showed rapid growth, regional lymph node involvement, tumor recurrence after surgery, and distant metastasis [3,8,11]. Also in our report, the rapid growth of the tumor tissue included invasion into the maxilla, even in the early clinical course, as a common characteristic in these three cases.…”

“…However, the rhabdomyosarcoma developing in the oral gingival tissue as described in this paper was rarely reported. In one previous report, two rhabdomyosarcoma cases in canine gingival tissue and the oropharynx area were described [8]. We encountered three cases of rhabdomyosarcoma developing in the maxillofacial area.…”

“…Cardiac, laryngeal, and bladder are predisposing portions of canine rhabdomyosarcomas, and several reports on this tumor have been published [1, 5-7, 9, 10, 13, 15, 16]. Although the number of cases has been quite limited, rhabdomyosarcoma has been reported to sometimes occur in the canine oral cavity [3,8,11]. In this paper, we report three cases of canine rhabdomyosarcoma in the canine oral cavity, located around the upper premolar teeth, which resulted in poor prognosis because of their refractory behavior to treatment and distant metastasis observed in the early clinical course.…”

Poorly Differentiated Uterine or Cervical Sarcoma in a Young Dog

“…In the previously mentioned survey of tumors in dogs less than 1 year of age, hemanigosarcoma and osteosarcoma were the most frequently recognized sarcomas with only one case of an undifferentiated sarcoma reported [3]. Interestingly, rhabdomyosarcomas were not reported in this study; however, this tumor has primarily been described in dogs over 1 year of age [1,[5][6][7].…”

“…In young dogs, this tumor has been reported to arise in many tissues including the uterus [1,[4][5][6][7]. In the previously mentioned survey of tumors in dogs less than 1 year of age, hemanigosarcoma and osteosarcoma were the most frequently recognized sarcomas with only one case of an undifferentiated sarcoma reported [3].…”