‘Lung-digit’ syndrome in a cat
A 10-year-old DSH cat presented for a single swollen digit on the left foreleg. A fine needle aspirate was taken (fig.1) and following the results, the digit was amputated and submitted for histopathology (figs. 2&3).
Final Diagnosis
Metastatic adenocarcinoma to the digit
Discussion
Adenocarcinomas affecting the digit of cats are not common but can either be primary (e.g. apocrine or eccrine origin) or metastatic. The morphological features of the neoplasm in this case including the presence of ciliated pseudostratified columnar epithelium (consistent with respiratory origin) and goblet cells are typical of metastatic disease. Primary pulmonary carcinomas are the most common neoplasms that can be associated with metastasis to the digits in cats. In some cases, multiple digits may be simultaneously affected and this should raise the suspicion of metastatic disease. Metastasis to the digits often occurs prior to the onset of clinical signs of respiratory disease however radiographs should help confirm the presence of a pulmonary mass.