Anal sac adenocarcinoma

Apocrine gland anal sac adenocarcinomas also have a tendency to metastasize to the regional lymph nodes, spleen, and eventually lungs and, less commonly, bones.

[5] The sublumbar (iliac) lymph nodes are the most common site of metastasis and can become larger than the original tumor.

[2] A poorer prognosis is associated with large tumor size (greater than 10 cm), hypercalcaemia, and distante metastasis.

[9] Early, incidental diagnosis of small anal sac masses may lead to a better prognosis with surgery alone (ongoing study).

[10] It is a disease of middle-age to older dogs and even though early reports described spayed females as more commonly affected, multiple recent studies have shown no gender overrepresentation.