Anal gland tumors are almost always malignant and may already have spread to regional lymph nodes and then to various internal organs by the time of the initial diagnosis. Even if the tumor has spread at the time of diagnosis and surgery, a permanent cure is rare, and the tumor can recur. The most common sign of anal gland cancer is a rectal mass or tumor. The tumors are often small in nature. In addition to the visible signs of a tumor, animals who are suffering from the disease may be constipated or have difficulty defecating (obstipation), anorexia, polydipsia, and may seem lethargic. Anal gland cancer, also called adenocarcinoma, appears as a rectal mass and is frequently found in the lymph nodes. This tumor is a disordered and purposeless overgrowth of cells originating from the modified sweat glands of an anal sac. The tumor is usually rapidly growing, almost always malignant (spreading), and extends deep into surrounding tissues. Tumors of the anal sacs (apocrine gland adenocarcinoma is the most common tumor type) are a serious but uncommon problem because they tend to invade surrounding tissues and metastasize (spread to distant tissues) even when the primary tumor is very small. The tumors are almost always only on one side.
Anal gland cancer is fairly uncommon, but is very serious when it occurs as it produces malignant tumors. Should your dog have an issue with his behind, it’s more. An anal gland tumor is not always obvious to the eye as the tumor may be growing inward. If your dog has an anal gland tumor, he may present some or all of these. An anal sac adenocarcinoma is an uncommon and aggressive malignant tumor found in dogs that arises from the apocrine glandular tissue of anal sac.