Lipomas

• Usually benign, lipomas are characterized by softly rounded fatty masses just under the skin. When allowed to grow, they may become uncomfortable or painful for your dog and may need to be removed surgically. Rarely, lipomas may become cancerous and spread throughout your dog's body. If your dog has a lipoma, your veterinarian may suggest performing a needle biopsy to determine whether or not the tumor is cancerous.
  
  

Basal Cell Tumors

• Basal cell tumors are common in middle-aged to older dogs and are especially prevalent in certain breeds, including wheaten terriers, Kerry blues and wirehaired pointed griffons. They usually appear on the head or neck and are usually benign. Because they may continue to grow and become infected, your veterinarian may suggest removing the basal cell tumor from your dog's ear.
  
  

Cutaneous Squamous Cell Carcinomas

• Cutaneous squamous cell carcinomas are usually found around the area of the head on older dogs. Standard poodles, basset hounds and bloodhounds frequently develop these raised bumps or plaques, which may easily become ulcerated and infected.
  
  

Melanomas

• Melanomas develop in the skin pigments of dogs and rapidly invade the areas surrounding the skin. They may become malignant and spread into the blood system and organs of your pet, so they should be treated surgically or with chemotherapy to prevent the spread of cancer.
  
  

Round Cell Tumors

• These tumors may appear as a raised round skin mass or lesion, open wound or large mass. Your veterinarian will probably excise the upper layer of skin around this tumor, or he may opt to remove the tumor surgically and follow up with chemotherapy.
  
  

Papillomas

• Paillomas (warts) are caused by a virus. They are usually not a cause for concern and often go away on their own without medication or treatment. They appear as benign, cauliflower-like growths that blossom outward from a "seed" under the skin.
  
  

Plasmacytomas

• Plasmacytomas are tumors of plasma cells that appear on the head or limbs of a dog. They may resemble round cell tumors because they are also raised, round masses. Your veterinarian may wish to biopsy a suspected plasmacytoma in order to make a proper diagnosis and begin treatment.