Case summary A 6-year-old, neutered male domestic shorthair cat was referred for evaluation of a recurrent subcutaneous mass on the right caudodorsolateral hip, 4 months after excision of a presumed feline injection site sarcoma (FISS). Advanced imaging revealed a bilobed soft tissue mass closely associated with the sciatic nerve and rectum. Surgical excision was limited by adjacent structures, and histopathology confirmed a sarcoma with incomplete margins. Definitive-intent radiation therapy was administered postoperatively. Follow-up imaging initially demonstrated no evidence of local recurrence. Approximately 9 months after completion of radiation therapy, the cat developed progressive pelvic limb paraparesis, fecal incontinence and urinary retention. MRI identified a large contrast-enhancing extradural spinal lesion extending from L5 to the sacrum, with suspected intramedullary invasion and marked thickening of the lumbosacral nerve roots. Surgical exploration with hemilaminectomy and spinal cord biopsy revealed a poorly differentiated sarcoma histologically similar to the original tumor. Progressive disease was confirmed on follow-up imaging, and palliative radiation therapy was administered. Despite treatment, the cat developed severe neurologic deterioration and was humanely euthanized. Relevance and novel information This report describes the first documented case of spinal cord invasion secondary to a FISS-like fibrosarcoma without local recurrence at the primary site. Perineural invasion along the sciatic nerve is proposed as a biologically plausible mechanism of tumor extension. This case highlights an uncommon but severe pattern of disease progression and underscores the importance of considering perineural spread in incompletely excised FISS-like tumors associated with major peripheral nerves.
Case summary A 10-year-old, castrated male domestic shorthair cat presented with stertor and severe respiratory distress caused by intratracheal masses occluding the majority of the tracheal lumen. Conventional endoscopic forceps biopsy yielded small tissue fragments, which were insufficient for a definitive histopathological diagnosis. Given the perceived high risk of tracheal resection and anastomosis, bronchoscopic cryotherapy with a 1.1 mm, flexible cryoprobe was performed for cryobiopsy and cryo-debulking. The masses occluded 80–90% of the lumen and were completely removed with cryotherapy, with immediate clinical improvement and decreased airway resistance (279 to 31 cmH 2 O/l/s). Haemorrhage was mild and controllable, and recovery was uneventful. Histopathology revealed tracheal myxosarcoma, a neoplasm not previously described in the feline trachea. The cat remained free of clinical signs for 7 weeks, after which clinical signs recurred, with radiographic evidence of regrowth. Pulmonary function testing suggested no substantial ventilatory compromise compared with preoperative findings; therefore, continued observation was chosen given the early recurrence. Three months after the initial intervention, bronchoscopy was repeated owing to gradually worsening clinical signs and confirmed tumour regrowth occluding approximately 50% of the lumen. A second cryotherapy session again achieved complete debulking and rapid resolution of signs. Relevance and novel information This report documents the first described tracheal myxosarcoma in a cat and demonstrates that bronchoscopic cryobiopsy can overcome the limitations of forceps biopsy while providing concurrent, airway-sparing palliative debulking. Bronchoscopic cryotherapy could serve as a feasible, minimally invasive diagnostic and therapeutic intervention for intraluminal tracheal masses in cats.
Case summary A 16-year-old, spayed female domestic shorthair cat was referred to the Schwarzman Animal Medical Center for evaluation of chronic, progressive eosinophilia accompanied by vomiting and weight loss despite normal appetite. Blood smear evaluation revealed immature eosinophils with dysplastic features and occasional giant forms. Abdominal ultrasound identified small-intestinal thickening, a hepatopathy and splenomegaly. Screening for feline leukemia virus, feline immunodeficiency virus and heartworm infection were negative. Chronic eosinophilic leukemia was suspected, although hypereosinophilic syndrome could not be ruled out. At the time of referral, the cat was receiving prednisolone and chlorambucil for suspected small cell gastrointestinal lymphoma, but showed persistent clinical signs and progressive eosinophilia. Chlorambucil was discontinued and toceranib was initiated alongside prednisolone. No adverse effects attributable to toceranib were observed. A partial response, defined as resolution of clinical signs and a 30% reduction in circulating eosinophils, was observed on day 39. A subsequent progression-free survival interval of 4 weeks was achieved. Progressive disease developed on day 75, and given declining quality of life, euthanasia was thereby elected on day 89. Relevance and novel information This case report is the first to describe the use of toceranib to treat suspected chronic eosinophilic leukemia, a rare and poorly documented disease process in cats. This novel therapeutic approach is the first publication of a partial response and stable disease in the treatment of suspected chronic eosinophilic leukemia in a cat.
Case summary This report describes a 14-year-and-9-month-old, male neutered cat with a primary adrenal tumour secreting aldosterone with pulmonary metastases, alongside concurrent hyperthyroidism and congestive heart failure. The cat presented with hyporexia and muscular weakness, including marked cervical ventroflexion. Hypokalaemia, hypertension, marked hyperaldosteronaemia and presence of a left-sided adrenal mass were consistent with primary hyperaldosteronism, and pulmonary nodules were detectable radiographically. Congestive heart failure and poor quality of life resulted in euthanasia. Microscopic examination identified an adrenocortical carcinoma, and the histological morphology and immunohistochemical labelling was similar between the primary tumour and pulmonary nodules. Relevance and novel information Primary hyperaldosteronism is an underdiagnosed condition of cats, causing hypertension and hypokalaemia. Excessive aldosterone is secreted by the adrenal glands and may be caused by tumours. Around half of aldosterone-secreting tumours in cats are malignant, although distant metastases have only been reported once previously. This is the first report of radiographically evident pulmonary metastases from an aldosterone-secreting adrenal tumour confirmed by immunohistochemical labelling.
Case series summary Two rescued juvenile cats with unilateral severe shoulder deformities (SDs) suspected to be secondary to septic arthritis were referred for further management. Comprehensive diagnostic evaluations confirmed SD with suspected septic arthritis in both cases. Because of the poor prognosis for preserving shoulder joint function, shoulder arthrodesis was performed to relieve pain and restore forelimb weightbearing ability. At 6 and 8 years postoperatively, both cats exhibited normal motor function in the affected limbs, no signs of lameness and maintained a good quality of life. No evidence of osteomyelitis or implant failure was noted. These findings suggest that arthrodesis may be a viable and effective long-term treatment option for irreparable shoulder joint disorders in cats. Relevance and novel information Shoulder joint injuries and disorders are less common in cats than in dogs, and only a limited number of reports exist in the small animal orthopaedic literature. In clinical practice, SD in small animals is rarely documented, with few references regarding its aetiology and pathophysiology. This report presents two cases of SD in rescued cats, demonstrating that shoulder arthrodesis can be an effective treatment for irreparable feline shoulder joint disorders. To the best of our knowledge, this is the first report to describe long-term clinical and radiographic outcomes of shoulder arthrodesis in cats with SD.
