Case Report Collision Tumour Affecting the Paranasal Sinuses of a Geriatric Donkey S

EQUINE VETERINARY EDUCATION / AE / APRIL 2012 163 Case Report Collision tumour affecting the paranasal sinuses of a geriatric donkey S. Witte*, P. O. E. Mueller†, C. Kosarek‡, J. L. Webb§ and E. W. Howerth§ Qatar Equestrian Federation, Doha, State of Qatar; Departments of Large Animal Medicine† and Pathology§, College of Veterinary Medicine, University of Georgia, Athens, Georgia; and ‡Animal Cancer Care Clinic, Fort Lauderdale, Florida, USA. Keywords: horse; donkey; sinonasal adenocarcinoma; spindle cell carcinoma; frontal sinus; maxillary sinus Summary The incidence of equine sinonasal tumours is difficult to quantify but they remain relatively uncommon (Head and Tumours of the paranasal sinuses are relatively uncommon Dixon 1999; Tremaine and Dixon 2001a). This makes the in the horse. A collision tumour occurs when 2 separate phenomenon of 2 separate neoplasms growing tumour types arise in close proximity to each other and concurrently even more unusual. Two separate neoplasms encroach on one another. This report describes the arising in close proximity to each other and invading each presence of neoplasia comprising glandular tissue and other are collectively known as a collision tumour. Collision spindle cells growing concurrently in the frontal and tumours have rarely been reported in the veterinary caudal maxillary sinus of a geriatric donkey. As far as the literature (Barnes et al. 1990; Inoue and Wada 2000). They authors are aware, this is the first description of a possible are uncommon in man and few case reports describe their collision tumour in an equid. location in the sinuses or nasal cavity (Cantor et al. 1981; Kumar et al. 2004; Satake et al. 2005). This report describes Introduction the clinical and histopathological findings in a 28-year-old donkey diagnosed with a collision tumour of the paranasal sinuses involving both the chonchofrontal and caudal Tumours of the equine paranasal sinuses and nasal cavity maxillary sinuses. can be divided into those that originate from the soft tissues and those that arise from cartilage and/or bone. Case history The most common neoplasm of the head is the squamous cell carcinoma (Acland et al. 1984; Hance and Bertone A 28-year-old male miniature donkey presented to the 1993; Dixon and Head 1999; Head and Dixon 1999). Other University of Georgia Veterinary Teaching Hospital soft tissue masses include adenomas, adenocarcinomas, (UGA-VTH) with a 3 week history of unilateral, right-sided undifferentiated sarcomas, fibrosarcomas, myxomas, epistaxis. The owner had noted small volumes of frank melanomas, haemangiosarcomas, angiomas, blood emanating periodically from the right nostril. angiosarcomas and lymphosarcomas (Hance and Attempts by the referring veterinarian to treat the Bertone 1993; Dixon and Head 1999; Head and Dixon 1999; condition with oral antimicrobials (trimethoprim/ Barakzai and Dixon 2003), Calcified tumours of the sulphonamides for 3 weeks) had been unsuccessful. The paranasal sinuses include ossifying fibromas, osteomas, donkey was otherwise healthy although there was a osteosarcomas, ameloblastic odontomas and compound previous history of laminitis 5 years prior to this or complex odontomas (Cannon et al. 1976; Roberts et al. presentation. 1978; Gibbs and Lane 1987; Lane et al. 1987; Schumacher et al. 1988; Hance and Bertone 1993; DeBowes and Case progression Gaughan 1998; Dixon and Head 1999; Head and Dixon 1999; Brounts et al. 2004; Orsini et al. 2004; Puff et al. 2006). During physical examination, the donkey was in good Recently, cementomas have been reported in 2 horses physical condition (weighing 380 kg), bright, alert and (Schaaf et al. 2007). responsive, and all vital parameters were within normal limits. A moderate volume of mucopurulent nasal *Corresponding author email: [email protected] discharge was emanating from the right nostril. During © 2011 EVJ Ltd 164 EQUINE VETERINARY EDUCATION / AE / APRIL 2012 a) a b b) Fig 2: Preoperative lateral skull radiograph demonstrating a circumscribed opacity within the frontal and caudal maxillary sinuses (a). A fluid line is evident wihin the caudal maxillary sinus (b). Skull radiographs demonstrated a region of increased opacity that was linearly demarcated from a region of decreased opacity within the caudal maxillary sinus. This was consistent with intrasinus fluid. In addition, a circumscribed opacity was noted within the frontal sinus which also projected into the caudal maxillary sinus (Fig 2). Complete blood cell count and fibrinogen were normal. Due to an inability to biopsy the mass via the nasal passage and the high index of suspicion for neoplasia, a surgical approach was made to the affected area via a nasofrontal osteoplastic flap (Freeman et al. 1990). Preoperatively, the donkey was administered potassium penicillin (22,000 iu/kg bwt i.v. q. 6 h) and gentamicin Fig 1: a) Preoperative endoscopic findings at the caudal right nasal (6.6 mg/kg bwt i.v. q. 24 h). Analgesic therapy consisted passage. The deformed and collapsed dorsal conchus (a) of phenylbutazone (2.2 mg/kg bwt i.v. q. 12 h). A well occludes the ethmoid region (b). b) View of the normal left ethmoid region. The normal dorsal conchus (a) and ethmoid circumscribed mass, measuring approximately 5 cm in turbinates (b) are visible. diameter was removed with relative ease. The tumour appeared to originate from the caudal maxillary sinus and ethmoid region and was carefully removed through a combination of digital and blunt dissection. Although the endoscopy of the upper portion of the respiratory tract amount of subsequent haemorrhage was not significant there was narrowing and partial occlusion of the caudal the sinus was packed with sterile gauze packing, which portion of the right nasal passage which restricted exited via a sinonasal fistula created at surgery and was evaluation of both the nasomaxillary aperture and the attached at the right nostril. The gauze packing was ethmoid region (Fig 1a). Endoscopy of the left ethmoid removed 48 h after surgery. Preoperative antimicrobials region demonstrated no abnormalities (Fig 1b). and nonsteroidal anti-inflammatory medication were © 2011 EVJ Ltd EQUINE VETERINARY EDUCATION / AE / APRIL 2012 165 populations (Fig 4). In some areas, the 2 neoplasms were separated by connective tissue while in other areas the 2 populations invaded one another. The first population was glandular in appearance and composed of small acini formed by small cuboidal cells and larger coalescing a follicles lined by cuboidal to columnar cells. Lumens of the acinar and follicular structures contained eosinophilic homogeneous to stringy secretion. The cells had lightly eosinophilic cytoplasm and a round nucleus with stippled c chromatin and one or 2 small nucleoli. Anisokaryosis was mild. Three mitotic figures were seen in 10 40x fields. The second population of cells was a densely cellular d proliferation of spindle-shaped cells arranged in thick b bundles separated by a moderate amount of fibrous stroma. These cells had a moderate amount of elongated eosinophilic cytoplasm and an oval to elongate nucleus with dense chromatin. Nuclei in adjacent cells sometimes lined up along the same end of the cells, producing a palisading appearance. Anisocytosis and anisokaryosis were minimal. Twenty-nine mitiotic figures were observed in 10 40x fields. Large areas of necrosis and haemorrhage were present but no vascular or lymphatic invasion by Fig 3: Endoscopic view of the right ethmoid region 3 months after either cell population was observed. The tissue sample surgery. Note the gross remodelling of the caudal aspect of the obtained at 3 month re-evaluation demonstrated dorsal concha (a) and the associated cicatrix and adhesion histological characteristics of the glandular portion of the formation (b) resulting from tumour resection. Also visible are small neoplasm alone. Moderate anisocytosis and anisokaryosis buds of tissue growing throughout the region (c) as well as mucus aggregates (d). was observed in this tissue and the mitotic figures had increased to 7 per 10 40x fields. Routine immunohistochemistry was performed on 4 mm continued for 3 days. On the third post operative day, the paraffin embedded sections of the mass removed at patient was discharged from the hospital. Financial surgery. The antibodies used and results of staining are constraints precluded further adjunct therapy. summarised in Table 1. Three months after surgery, the donkey presented to the hospital for re-evaluation. The donkey reportedly had right-sided serosanguinous nasal discharge for 2–3 weeks Discussion post surgery but had otherwise been doing well. Physical examination was normal. The site of the sinus flap was A portion of this sinonasal tumour was glandular (epithelial) completely healed and there was no evidence of nasal in origin while a separate portion was composed of discharge. With the exception of a small amount of fluid spindloid cells that were also epithelial in origin, based present within the caudal maxillary sinus, radiographs of on immunohistochemistry. Whether these cell groups the skull revealed no abnormalities. The right ethmoid differentiated along 2 different lines from a tumour of stem region was visible on endoscopy and was covered in a cell origin or 2 separate tumours had arisen and collided in web of mucous and fibrous material (Fig 3). Small buds of this patient (a collision tumour) is not clear. Based on the tissue were biopsied for histopathology. Approximately 13 histopathological appearance a diagnosis

Load more