Meningeal carcinomatosis and spinal cord infiltration caused by a locally invasive pulmonary adenocarcinoma in a cat

Abstract

Case summaryA 12-year-old domestic shorthair cat was presented with acute non-painful hindlimb proprioceptive ataxia localising to T3–L3 spinal cord segments. MRI revealed paravertebral muscular hyperintensity on T2-weighted images at the level of T7–T8 vertebrae. The cat improved on conservative management but deteriorated 3 months later. Repeated MRI showed meningeal enhancement at the same level and hyperintensity of the paravertebral musculature extending to the right thoracic wall and pleural space on short tau inversion recovery images. Thoracic CT showed mineralised lesions of the right lung, restricted pleural effusion and expansile bone lesions affecting multiple ribs. The cat had been treated for pyothorax 5 years earlier but manifested no current respiratory signs. Cerebrospinal fluid (CSF) examination showed lymphocytic pleocytosis but no neoplastic cells. Biopsy of the affected muscles and cytology of the lung and pleural lesions suggested a malignant epithelial cell tumour. Post-mortem examination confirmed a pulmonary adenocarcinoma locally infiltrating the thoracic wall, T7–T8 vertebrae and the spinal cord white matter. Meningeal carcinomatosis was detected with neoplastic cells invading the ventral median fissure of the spinal cord. No metastases were observed in other organs, indicating that neoplastic cells reached the spinal cord by direct extension.Relevance and novel informationSpinal meningeal carcinomatosis has not been reported in dogs or cats with extraneural tumours but is a well-recognised condition in humans. A metastatic cause of meningeal enhancement should be considered in patients with neurological signs of unknown origin. Imaging findings and CSF results can be non-specific.

Meningeal carcinomatosis secondary to a suspected pulmonary carcinoma in a cat and comparison with human literature

“…In feline medicine, meningeal carcinomatosis has been reported only in three cats. Two cats had intracranial meningeal carcinomatosis secondary to a squamous cell carcinoma of the ear pinnae5 and the third cat was diagnosed with meningeal carcinomatosis in the spinal cord from a pulmonary adenocarcinoma 6. This is the first report to describe MRI findings of meningeal carcinomatosis with concurrent intraparenchymal brain metastases in a cat.…”

“…Two cats had intracranial meningeal carcinomatosis secondary to a squamous cell carcinoma of the ear pinnae 5 and the third cat was diagnosed with meningeal carcinomatosis in the spinal cord from a pulmonary adenocarcinoma. 6 This is the first report to describe MRI findings of meningeal carcinomatosis with concurrent intraparenchymal brain metastases in a cat. In this case, it was hypothesised that a pulmonary carcinoma was the primary tumour, given the unremarkable abdominal ultrasound, the imaging and pathological findings in the thorax and brain.…”

“…Meningeal carcinomatosis is the most likely diagnosis when imaging studies show concurrent involvement of meningeal and intraparenchymal lesions in a patient with known cancerous disease 2. In veterinary medicine, the information regarding meningeal metastases is scarce and only two publications refer to feline cases 5 6…”

Pulmonary adenocarcinoma causing oesophageal and bronchial compression in a cat with concurrent peritoneopericardial diaphragmatic hernia

“…Although several authors report a predilection for bony metastasis, the evidence to support this varies between surveys and no sign of such process was identified in the case presented. [15][16][17][18][19][21][22][23][24][25][26][27][28][29][30][31][32][33] Other extrathoracic sites of metastasis reported in previous studies include liver, kidneys, intestine, spleen, pancreas, salivary glands, meninges, spinal cord, eyes, trachea and aorta. [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34] To the authors' knowledge, simultaneous involvement of oesophagus and heart from a pulmonary carcinoma, as described in the present case, has been previously described only once.…”

Feline abdominal ultrasonography: What’s normal? What’s abnormal? Abdominal lymph nodes, peritoneal cavity and aorta

“…Carcinomatosis refers to the widespread dissemination of neoplasia throughout a body cavity (peritoneal or, less commonly, pleural or cerebrospinal) and encompasses metastatic spread from epithelial (carcinomatosis), mes-enchymal (sarcomatosis) and haematopoietic (lymphomatosis) tumours. 37–42 Based on two studies comprising a total of 24 cats with abdominal carcinomatosis, primary tumours most commonly originated in the pancreas (n = 9), hepatobiliary system (n = 7) or small intestine (n = 5). 37,41 The vast majority of these cats had carcinomatosis due to spread of a primary epithelial tumour (n = 21).…”