Computed tomography of a cat with primary intratracheal lymphosarcoma before and after systemic chemotherapy

Radiographic and computed tomographic characteristics of intraluminal tracheal adenoma in a cat

A 13-year-old spayed female Persian cat presented with dyspnea and nasal discharge. Thoracic radiography revealed a dome-shaped soft-tissue opacity in the carina. Computed tomography confirmed a soft tissue-attenuating mass in the carina and the left and right proximal main bronchi that appeared to arise from the tracheal wall. Tracheoscopy revealed an intraluminal broad-based mass with multilobulated borders at the same location. Histopathological evaluation revealed a benign neoplastic process of the glandular epithelial lineage, which was considered an adenoma. Tracheal adenomas should be included in the differential diagnosis of tracheal masses.

Retrospective study of feline tracheal mass lesions

OBJECTIVES

This multicentre, retrospective observational study aimed to describe the clinical presentation, diagnostic methods, treatment and outcomes of cats with tracheal masses.

METHODS

Eighteen cats from five academic or secondary/tertiary animal hospitals were included.

RESULTS

The median age at diagnosis was 10.7 years (mean 9.5; range 1-17). There were nine castrated males, seven spayed females, one intact male and one intact female. Fourteen (78%) were domestic shorthairs, one (6%) was an Abyssinian, one (6%) was an American Shorthair, one (6%) was a Bengal and one (6%) was a Scottish Fold. The most common presenting complaints included chronic respiratory distress or dyspnoea (n = 14), followed by wheezing/gagging (n = 12), coughing (n = 5) and voice changes (n = 5). There was cervical tracheal involvement in 16/18, and two showed involvement of the intrathoracic trachea. The following methods were used for diagnosis: ultrasound-guided fine-needle biopsy (UG-FNB) and cytology (n = 8), bronchoscopic forceps biopsy and histopathology (n = 5), surgical resection and histopathology (n = 3), forceps biopsy via an endotracheal tube (n = 1) and histology of tissue sputtered from a cough (n = 1). Lymphoma was most often diagnosed (n = 15), followed by adenocarcinoma (n = 2) and squamous cell carcinoma (n = 1). Most lymphoma cases received chemotherapy with or without radiation according to various protocols, and partial (n = 5) or complete responses (n = 8) were noted. Kaplan-Meier survival data for cats with lymphoma revealed a median survival time of 214 days (95% confidence interval >149 days), which was significantly longer than that of other types of tumours (21 days).

CONCLUSIONS AND RELEVANCE

Lymphoma was the most prevalent diagnosis, and showed a good response to chemotherapy with or without radiation therapy. Various diagnostic procedures were performed, and UG-FNB and cytology are good diagnostic procedures for cervical tracheal lesions. Owing to the variety of treatment protocols at different centres, it was impossible to compare outcomes.

Tracheal Squamous Cell Carcinoma Treated with Tracheal Resection and Anastomosis in a Cat

A 10-year-old male castrated domestic shorthair cat presented for a suspected tracheal mass. Radiographs confirmed an intraluminal tracheal mass. Tracheal resection and anastomosis of 5 tracheal rings was performed with minimal, mild intraoperative complications and no postoperative complications. Histopathology of the tracheal mass revealed a diagnosis of squamous cell carcinoma (SCC) with incomplete margins both cranially and caudally. Further treatment, including surgical revision, radiation therapy, or chemotherapy, was recommended. At the time of publication, no further treatment has been initiated, and a scheduled consultation with the oncologist has been canceled. The cat is doing well at home with no reported signs of recurrence 120 days postoperatively. This is the first report of a cat with a tracheal SCC to be treated with a tracheal resection and anastomosis and only the third feline tracheal SCC to be treated in the veterinary literature.

Periaortic lymphoma in a cat

Case summary

A 14-year-old neutered male Siamese cat was presented with a 3 month history of lethargy, inappetence, dehydration, hindlimb ataxia and intermittent proprioceptive deficits in the hindlimbs. Physical examination revealed low body condition score (1.75/5), pallor and bilateral basilar grade II/VI systolic heart murmur. Neurological examination revealed hindlimb ataxia, severe atrophy of the hindlimb musculature, intermittent hindlimb proprioceptive deficits and normoreflexia. Clinicopathological investigations revealed non-regenerative anaemia (haematocrit 0.17 l/l; reference interval [RI] 0.24–0.45 l/l) and increased feline pancreatic lipase concentration (Spec fPL test [IDEXX] 8.3 μg/l; RI 0.1–3.5 μg/l). Feline leukaemia virus antigen and feline immunodeficiency virus antibody tests were negative. Thoracic and abdominal imaging revealed a soft tissue structure in the area of the thoracoabdominal aorta. CT confirmed a periaortic contrast-enhancing mass extending from the level of T9–L2, with associated intervertebral infiltration at the level of T11–T12. Post-mortem examination confirmed the presence of a solid, white, multinodular, well-demarcated mass encircling the aorta extending from T9–L2. Based on histopathology and immunohistochemistry, a diagnosis of B-cell lymphoma was made. Lymphoma was also identified histopathologically within the kidneys and spleen. Evidence of mild Wallerian degeneration was present within the spinal cord, indicating compression at the level of the periaortic mass.

Relevance and novel information

To our knowledge, this is the first report of periaortic lymphoma in the cat. Although periaortic tumours are exceptionally rare in veterinary medicine, lymphoma should be considered as a differential in cats.

Successful treatment of tracheal lymphoma in a Siamese cat

CASE SUMMARY

An 8-year-old female spayed Siamese indoor cat presented with a 3 week history of inspiratory dyspnoea, stridor and open-mouth breathing after exercise. Laryngoscopy, tracheoscopy, bronchoscopy and retroflexed nasopharyngoscopy were performed, and identified a multilobulated intraluminal mass within the trachea. Brush cytology was performed on the mass but was inconclusive in providing a definitive diagnosis. A CT scan of the neck failed to identify an obvious intraluminal mass and was negative to contrast uptake. Surgery was performed and seven rings of the trachea were removed to enable the complete excision of the mass. Histopathology of the excised mass was consistent with B cell lymphoma. After surgery, chemotherapy treatment was started. At the time of writing, 20 months since diagnosis, the cat remained clinically well, with no clinical signs or recurrence of macroscopic disease on endoscopic evaluation.

RELEVANCE AND NOVEL INFORMATION

Upper airway endoscopy was considered to be an essential diagnostic tool in this case presenting with signs of upper respiratory dyspnoea. Moreover, combined surgery and chemotherapy were considered effective treatments and positively affected the long-term prognosis of this patient.

Invasive tracheal neoplasia in eight cats: descriptive cases and review of the current literature

Case series summary

This case series describes eight cases of invasive tracheal neoplasia that were recognized between the years 1989 and 2014 from a single tertiary referral hospital. This is a disproportionately high number of cases compared with the total number of reports in the current literature.

Relevance and novel information

Invasive tracheal neoplasia is uncommonly diagnosed in domestic cats. Feline tracheal tumors mimic other upper respiratory diseases making diagnosis challenging. Prognosis is guarded to grave, with most cats surviving less than 1 month after beginning treatment. Severe respiratory distress in cats often warrants humane euthanasia. Appropriate clinical suspicion and awareness can expedite diagnoses leading to prolonged survival rates with appropriate treatments. This case series represents the largest number of feline tracheal tumors reported and also describes the first unique histological presentation of what the authors believe to be a poorly differentiated tracheal carcinoma.