Laryngeal Rhabdomyosarcoma in a dog: case report

Abstract

The larynx is part of the upper respiratory tract and is responsible for phonation. It allows air to pass between the pharynx and the trachea, but prevents food from entering the airways. Laryngeal neoplasms, including rhabdomyosarcomas, are uncommon in dogs. However, these tumors can trigger numerous progressive clinical signs related to respiratory difficulty and altered phonation. The diagnosis of laryngeal cancer should be made based on the history and symptoms of the patient, combined with complementary tests. The treatment of choice is surgical excision, combined or not with chemotherapy. In view of the low incidence of laryngeal cancer, the objective of the present work was to describe a case of laryngeal rhabdomyosarcoma detected during necropsy of an adult dog and diagnosed by histopathology, in addition to raising awareness about the importance of the diagnosis and early therapy for the quality of life and survival of affected patients. The results showed that the location of the tumor impaired its early diagnosis. Although malignant, the animal did not develop metastases as has been described in the literature.

Surgical management of a laryngeal rhabdomyosarcoma in a cat

“…[2][3][4][5][6][7] There is currently one reported case of a laryngeal RMS in a dog, which was diagnosed on necropsy. 8 This case drew similarities with previously reported cases of laryngeal disease in cats. The presenting clinical signs were consistent with those most commonly reported, namely stridor and dyspnoea.…”

“…13 In the single veterinary case report of a laryngeal RMS in a dog, the diagnosis was based on the appearance of a proliferation of neoplastic cells originating from skeletal muscles. 8 The cells were noted to be atypical with a marked pleomorphism and the cytoplasm was noted to be scarce and irregular. There was no description of immunohistochemistry being performed within the report.…”

Clinical, pathological and therapeutic findings on lingual rhabdomyosarcoma in a dog - case report

“…Although fine-needle aspiration cytology is a quick, inexpensive and minimally invasive technique (Murakami et al, 2010), it is not always reliable as the quantity of specimen collected may be insufficient for analysis and diagnosis; therefore, histopathology is usually indispensable (Brockus and Myers, 2004;Chapman et al, 2008). The histopathological findings of the present case were similar to those found by Dias et al (2018) in a dog with laringeal rhabdomyosarcoma. In the current study, immunohistochemistry was performed to identify proteins in order to confirm the origin of the neoplasm since the lack of differentiation of the tumour could cast doubt on the diagnosis.…”

“…Regarding the markers, the protein myosin, present in muscle contractions, characterized a skeletal muscle neoplasm that is the muscular type of the tongue. Despite the importance of immunohistochemistry in the investigation of neoplasms of the stomatognathic system, there are descriptions of the diagnosis of rhabdomyosarcoma in maxilla of three dogs (Nakaichi et al, 2007) and larynx of a dog (Dias et al, 2018) only by histopathological examination.…”

“…Tumours of the tongue are uncommon in small animals, corresponding to only 4% of all oral and non-odontogenic sarcomas of soft tissues connected to the skeletal musculature (Nakaichi et al, 2007;Kato et al, 2012). They are rare in the oral cavity (Chapman et al, 2008;Murakami et al, 2010;Kimura et al, 2013;Dias et al, 2018) and originate from primitive mesenchymal cells, are malignant, solid, aggressive and have high metastatic potential (Murakami et al, 2010;Kato et al, 2012;Kimura et al, 2013).…”