Dog occiput: what is that bump on your dog’s head?
The occiput, or occipital bone, takes its name from the Latin word for “back of the skull.” It’s the part of the skull that connects to your dog’s neck and acts as a passage for their spinal cord, allowing your dog to move their head in relation to their spine.
The size of the occiput will depend on your dog’s breed. Some dog breeds will have a pronounced occiput that’s easy to feel through the skin of their head, while others will have a smaller bump. Hounds, for example, are known for having a pronounced occiput.
Because the bump is a part of your dog’s skull, it should remain around the same size throughout your dog’s life unless there’s a medical issue.
Types of lumps and bumps – benign vs malignant
Benign lumps and bumps lack the ability to invade other tissues and spread to sites beyond where they are present. The vast majority cause little concern, however those that continue to grow can cause problems, like restricting movement or breathing because of the lump’s size, or your dog keeps scratching them because they’re irritating. If benign lumps are causing problems, removal should be considered.
Lipomas are the most common benign mass dogs can get; they’re often found under the skin of older dogs, and are more common in obese dogs. They tend to be round, soft tumours of fat cells that grow very slowly and rarely spread, so it can take up to six months before you see any change. Lipomas can be easily diagnosed with FNA.
If they become very big or hinder movement (e.g. growing behind a leg or in the armpits), your vet might recommend removal.
Abscesses are swollen lumps that contain an accumulation of pus under the skin caused by an infectious agent. They will generally need to be drained under sedation and copiously flushed with a clean antibacterial solution. In some cases, your vet will prescribe antibiotics if they deem it necessary.
Hives on dogs are similar to those on humans – a rash of round, red weals on the skin that itch and swell due to a reaction of the skin to allergens such as a bee sting or contact allergy. They will often resolve on their own, however sometimes they need steroids or antihistamines to provide relief.
Sebaceous cysts are hard, cystic material under the skin that can form due to a blocked sebaceous gland. They appear like swellings with a creamy matter inside them. The swellings sometimes become red and sore. They’re usually found in older dogs in the middle of their back and can be diagnosed with FNA. Most of them don’t cause problems, so they’re usually left alone unless they’re infected or irritate your dog.
Histiocytomas are an ulcerated nodule (or red button-like lump) often found in young dogs, particularly on their limbs. They normally go away quite quickly but you should still have them checked by your vet as they can imitate some very nasty cancerous tumours.
Sebaceous adenomas are tumours of sebaceous glands that appear as multiple wart-like growths. They’re more common in woolly-haired older dogs like Poodles, Maltese, Bichons, and their crossbreeds. A biopsy is required for diagnosis but vets can often diagnose these lumps by just looking at them due to their classic appearance and slow growth. Most of them don’t cause problems, but those that are ulcerated, irritate your dog, or are being licked or chewed at by your dog should be removed.
Perianal adenomas are tumours that grow around the anus, mostly in non-desexed older dogs. Any lump or bump around the anal region requires proper assessment and investigation due to malignant tumours in this area being common.
Warts are more common in puppies, older dogs and dogs that are immunocompromised, and look like small skin tags or several small lumps. They’re usually found on the head and face and are caused by a papillomavirus. Dogs that go to a doggy daycare or dog parks can get warts due to close social contact with other dogs. A biopsy is required for diagnosis but vets can tell due to their classic feathery appearance. No treatment is necessary, as they’ll usually go away by themselves after a few months. However, they can irritate your dog, and if this occurs removal should be considered.
Granulomas can be raised red lumps that may have a surface crust, or they can be found under the skin and have a firm consistency. They’re often not adhered to muscle. They can look similar to a highly aggressive tumour so vets will usually recommend a biopsy/surgical removal or FNA. Surgical excision is often required for treatment.
Haemangiomas are tumours of blood vessels or underlying tissues of the skin. Sun exposure can lead to their development, however this isn’t always the case. Diagnosis is done by a biopsy or surgical excision with the sample being tested by a pathologist. This is always recommended as these tumours can change over time to become malignant. Surgical excision is curative if the tumour is benign.
Malignant lumps and bumps grow and can spread through the body and affect organs like the liver and lungs, along with the brain and bones. They can spread by local growth (destroy nearby tissues) or by metastasis (tumour cells enter the bloodstream or lymphatic system to spread to other body sites). It’s important that malignant lumps and bumps on your dog are surgically removed as soon as they’re diagnosed to keep them from spreading and causing devastating consequences. Chemotherapy and radiation therapy are also often used to prevent further spread.
Mast cell tumours are a tumour of the immune system blood cells, and comprise of up to 25% of all tumours. They’re most common in dogs older than 8 years of age. Mast cell tumours can look like many other tumours, so it’s vital to have them diagnosed accurately by a vet. Usually vets will start with a FNA. When diagnosed, it’s important to check if the tumours have spread to other organ systems.
Fibrosarcomas are locally invasive tumours of the skin’s connective tissue that grow fast. They’re common in large breeds. A biopsy is required for diagnosis, as they feel like lipomas and can be mistaken for them if FNA isn’t done. They usually spread by local invasion and can be difficult to remove, as prompt, careful resection with a wide surgical margin is required.
Melanomas in dogs are not caused by sunlight and are a lot less malignant than human melanomas. Canine melanomas are tumours involving cells that give pigment to the skin. They can be benign or malignant and appear as dark lumps on the skin that grow slowly. More aggressive tumours grow on the mouth and legs. They have to be removed but they can recur.
Squamous cell carcinomas are skin cell tumours found on unpigmented or hairless areas such as the eyelids, vulva, lips and nose, and present as raised, crusty sores. It’s another tumour caused by too much sun exposure.
They usually grow by local invasion and should be removed. If they’re left for too long, they can cause great deformities and pain, as well as spread to lymph nodes and other organs, ultimately resulting in death.
Mammary carcinomas are cancerous growths of the mammary glands. They’re more common in non-desexed female dogs. Lumps in the mammary glands can be benign, however it’s worth noting that mammary tumours in male dogs are often always malignant. They spread by metastasis to the lymph nodes, other mammary glands and organs. In most cases, it’s recommended that you get mammary lumps surgically removed, and chemotherapy is an option after removal.
Osteosarcomas are the most common bone tumour, especially in large male dogs. They’re caused by abnormal bone cell growth, unusual hormone stimulation, a previous fracture in the area, or genetic factors. They can cause bumps or lumps to form in the bone, usually in the limbs, and often spread to the lungs by metastasis. They’re diagnosed with biopsy and lab tests of bone and skin tissue. They need surgical removal, which may include amputation of the affected limb.
Chondrosarcomas are the second most common bone tumour and usually occurs inside of the nose. They’re also caused by abnormal bone cell growth, unusual hormone stimulation, or genetic factors. A biopsy and lab tests of bone and skin tissue are also required for diagnosis.
Treatment of nearly all malignant tumours requires surgical excision and chemotherapy and/or radiation. When a lump or bump is diagnosed as malignant, your vet will want to x-ray other areas and/or ultrasound the abdomen to determine if the tumour has metastasised. In some circumstances, the vet will recommend a CT examination to determine exactly where in the body the malignant cells are. This is called staging.
Signs that our dog should see a veterinarian
The main sign that you should seek guidance from a veterinarian is if you notice that your dog’s occiput has gotten larger or more noticeable, especially for a longer period of time. Other signs that you should see a vet include:
Pointy Head Dogs: Is the bump a problem?
The overall health of a dog is often reflected in their skin. Dogs can get lumps, bumps, and cysts from normal aging, or they can be signs of a problem.
There are two major types of lumps and bumps on dogs: malignant (cancerous) and benign (not cancerous). However, you can’t tell the type or severity of a growth just by looking at it. A veterinarian can take a sample of cells to give you a diagnosis and appropriate treatment plan.