Oncology

Introduction

The Oncology Research Group at the Animal Health Trust is carrying out research that is intended to enable the clinicians to better diagnose, treat and cure more dogs and cats in the future. We hope that by identifying the underlying causes of cancer in cats and dogs, it may be possible to reduce the numbers of animals that suffer from these diseases.

The Oncology Research Group was formed to combine the expertise and experience of oncologists, pathologists, soft tissue surgeons, epidemiologists, neurologists, canine and feline internal medicine clinicians and molecular biologists. We are currently investigating many different aspects of a number of the most common canine and feline cancers, in particular lymphoma, mast cell tumours and brain tumours of dogs and oral squamous cell carcinomas of cats. Our investigations include:

identification of causes and risk factors for these tumours
developing and improving methods for detection of these tumours at an early stage
improving our predictions of how these tumours will behave and respond to treatment
developing improved therapies for the tumours

We do not use any experimental animals in our research, but rather we rely on obtaining samples of naturally occurring tumours that are collected from patients by veterinary surgeons as part of the normal diagnostic clinical procedures.

Canine mast cell tumours

Introduction

Mast cell tumours are the most common skin cancer in dogs and primarily affect middle-aged and elderly dogs. They display a wide range of severity ranging from the benign to the malignant, but 70% of mast cell tumours can be cured by surgery and local radiotherapy.

Success Story- Tilly Coad
Current research
How pet owners/breeders can help our research
Further information for vets

Canine lymphoma

Introduction

Lymphoma is the most frequent life-threatening cancer in dogs, accounting for up to 20% of all tumours and affecting as many as 24 out of every 100,000 dogs. In the most common form of the disease, cells (lymphocytes) become cancerous in one or more lymph glands where they form tumours called lymphoma (or lymphosarcoma). Lymphoma may occur in dogs of any age, but is most common in dogs between 6-9 years old. If untreated, death can result within 8-12 weeks of diagnosis. Lymphoma is very sensitive to chemotherapy and up to 80% of dogs treated will go into remission, for an average of 12 months. A small proportion of dogs will survive for longer than 2 years.

Current research
How pet owners/breeders can help our research
Further information for vets

Canine brain tumours

Introduction

Meningiomas are the most common primary brain tumours in dogs, constituting approximately 40% of the brain tumour cases seen in the Small Animal Clinic at the Animal Health Trust. As in humans, the tumours can arise spontaneously. Glial cell tumours (also referred to as gliomas) are the second most frequent brain tumour in dogs, and comprise different subtypes with a highly variable response to treatment. Dog breeds with long, narrow heads appear to be more susceptible to developing meningiomas, whilst dogs with short, wide heads have a higher risk of developing glial cell tumours. Most primary brain tumours develop in older dogs.

Current research
How pet owners/breeders can help our research
Further information for vets

Other cancers of interest

Canine haemangiosarcoma

Introduction

Haemangiosarcomas are tumours (of middle aged and older dogs) derived from cells that form the inner walls of blood vessels. The tumours develop in the skin (‘dermis’, or ‘subcutis’ layers), and in the spleen, the liver and the heart. Skin tumours have a favourable prognosis following surgical removal, but tumours that affect internal organs have a much higher risk of spreading to other parts of the body. Dogs with such tumours typically survive for only a few weeks and sometimes considerably less. Haemangiosarcomas are common in medium and large breeds of dogs, with a reported incidence of 14 per 100000 dogs per year across the entire UK dog population.

Current research
How pet owners/breeders can help our research
How vets can help our research

Canine histiocytic sarcoma

Introduction

Histiocytic sarcomas are a type of cancer that arise through the uncontrolled growth of cells called histiocytes (also called macrophages) in the tissue (‘connective tissue’) that supports and surrounds organs within the body. These tumours can develop externally in the skin (flank, muzzle, nose, eyelids and scrotum), within eyes and peripheral lymph nodes, or internally within the spleen, liver, lungs, and bone marrow. If the cancer spreads (usually to a local lymph node and the liver and/or lungs) from a single initial site (often the soft tissues of the extremities around joints), it is known as a localised histiocytic sarcoma. If primary tumours develop in multiple organs in the body at the same time the cancer is referred to as disseminated histiocytic sarcoma (formerly called malignant histiocytosis). A dog with a single tumour on an extremity has the best prognosis if treated early by surgery and radiotherapy, or by amputation of a limb. Dogs with multiple tumours cannot easily be treated by surgery, and the cancer is poorly responsive to chemotherapy and progresses rapidly.

Current research
How pet owners/breeders can help our research
How vets can help our research

Canine mammary tumours

Introduction

Mammary tumours are one of the most common tumours to affect older female dogs. Approximately 50% (some authorities suggest that 70% is a more realistic figure) of mammary tumours are benign, and many tumours that look (to a pathologist) as though they will be malignant also follow a relatively benign course and do not spread elsewhere. Therefore many dogs can have a good outcome if the tumour is treated with an adequate surgical procedure. Up to 50% of bitches may present with multiple tumours affecting different glands, and these tumours can be of types, and so biopsies of all the tumours need to be examined by a pathologist. Entire bitches are more likely to develop mammary tumours, both malignant and benign. Early spaying (before the second season) can decrease the risk of tumours developing.

Current research
How pet owners/breeders can help our research
Further information for vets

Canine melanoma

Introduction

Melanomas are about 4% of all tumours in dogs, and arise from cells (containing the pigment melanin) that occur in the skin (‘cutaneous melanoma’), in the mouth (‘oral melanoma’), under toe nails (‘ungual melanoma’), and in the eye (‘ocular/uveal melanoma’). The severity of a melanoma depends upon location, with oral tumours being the most likely to spread. While melanomas occur rarely in many dog breeds, a number of breeds develop these cancers more often.

Current research
How pet owners/breeders can help our research
Further information for vets

Canine osteosarcoma

Introduction

Osteosarcoma is the most common bone cancer of dogs. The tumours usually develop in the long bones of the legs close to the joints, such as by the stifle, or close to the shoulder joint. The early signs of osteosarcoma are lameness and pain (which may be intermittent), limb swellings and fractures at the tumour site. The tumour is extremely malignant and for more than 90% of affected animals, which do not receive chemotherapy following limb amputation, the cancer will spread usually to the lungs), and life expectancy varies from a few weeks to 3-6 months. However, 40-60% of dogs that do receive chemotherapy survive for 12 months, and indeed half of these survive long term.

Current research
How pet owners/breeders can help our research
How vets can help our research

Canine soft tissue sarcoma

Introduction

Soft-tissue sarcomas are a group of tumours derived from soft tissues (muscles, tendons, fibrous tissue, fat, blood vessels, nerves, and tissues around joints). The behaviour of the tumours depends upon their subtype and location. Dogs are usually treated by surgery which may need to be followed by local radiotherapy.

Current research
How pet owners/breeders can help our research
How vets can help our research