Tumor in animals

Tumor in animals or Tumour may be defined as “an abnormal mass of tissue, the growth of which extends uncontrolled, in comparison to the normal tissue and persists in the same excess even after cessation of the stimuli which evoked the change.”

The term “neoplasm” is a Greek word used primarily for new formations or new growths.

Classification of Tumors-

Tumors are two types- Benign and Malignant.

Benign	Malignant
Grow slowly	Grow rapidly
Locally grow to great size	Create metastases
Don’t invade the neighbouring tissue	Invade and destroy neighboring tissues.
Usually do not return after surgical removal	Recurrence after surgical removal

Tumors are more common in canines (Dogs), here is some types of tumor locations-

Skin – Common in older dogs (often benign) but much less common in cats (malignant).

Breast – Fifty percent of all breast tumors in dogs and 85% of all breast tumors in cats are malignant.

Testicles – Testicular tumors are rare in cats and common in dogs, especially those with retained testes.

Bone – Bone tumors are most commonly observed in large breed dogs and rarely in cats. The most common sites are leg bones, near joints.

Head and Neck – Cancer of the mouth is common in dogs and less common in cats. A mass on the gums, bleeding, odor, or difficult eating are signs to watch for.

Horse and cattle are more often affected than sheep, pig and goat-

Fibropapillomatosis of the skin, mucosa of mouth, esophagus and urogenital organs are often seen in domestic animals. Fibroma is more common in horses, cattle and dogs.

Old animals are affected more commonly than young ones by tumors.

Terminologies of tumors-

Name of tumor	Cell type
Fibroma	Fibrous connective tissue
Chondroma	Cartilaginous tissue
Osteoma	Bony tissue
Odontoma	Tooth substances
Myoma	muscular tissue
Myxoma	Cardiac skeleton
Lipoma	Adipose tissue
Neuroma	Nerve cells and fibers
Leiomyoma	Smooth muscle
Rhabdomyoma	Skeletal tissue
Haemangioma	Blood vessels
Meningioma	Meninges
Teratoma	Germ cells
Papilloma	Skin or mucous membrane
Adenoma	Glandular epithelium
Basal cell tumor	Basal cell of skin
Hepatocellur adenoma	Hepatocytes
Glomus tumor	Melanocytes
Non-Hodgkin lymphoma and Hodgkin lymphoma	Lymphoid cells
Leukaemia	Hematopoietic cells

Diagnosis of tumors-

• Clinical examination – location, size and consistency can be diagnosed
• Radiography – bones and vascular organs tumor can be seen
• Biopsy – exploratory cytology can be analyzed

Treatment of tumors-

These treatment option considered for tumors-

1. Prophylactic treatment of tumors
2. Definitive excision of tumors
3. Palliative treatment of tumors

1. Prophylactic treatment of tumors-

Prophylactic treatment is undertaken either to reduce the anticipated incidence rate of a particular tumor type or the rate of recurrence of a neoplastic disease after therapy.

• Mammary tumors in bitch– Spaying between 6 and 12 months of age will greatly reduce the risk of breast cancer. Surgery is the treatment of choice for this type of cancer.
  • Benign vaginal tumor– ovariotomy greatly reduce the risk of Benign vaginal tumor.
• Testicular tumors (Seminoma and sertole cell tumor) – Castration greatly reduce the risk of Testicular tumors (Seminoma and sertole cell tumor).

2. Definitive excision of tumors-

Definitive excision refers to use of surgery as the sole treatment procedure without adjunctive radiotherapy or chemotherapy.

• Local excision: The removal of a neoplastic mass with the minimal amount of surrounding normal tissue.
• Wide local excision: Removal of a significant predetermined margin of surrounding tissues together with the primary mass.
• Radical local excision: Removes of a tumor with anatomically extensive margins of tissue extending into fasuil planes which are undisturbed by the primary growth of the tumor us termed radical local excision or compartmental excision. Eg: sarcomas.

3. Palliative treatment of tumors-

Palliative treatment of tumors is a procedure that remarkably improves an animal’s quality of life by providing pain relief, or relieving poor function, despite the presence of unsolved systemic neoplastic disease.

For Example, Limb amputation in case of osteosarcoma and Splenectomy in a case of Bleeding haemorrhage of sarcoma.

Differential diagnosis for Tumor-

Hernia

History of recent injury and swelling. Hernial ring can be palpated.

Haematoma

Haematoma forms due to coagulation of blood or serum. It is doughy on palpation and forms immediately following an injury. Haematoma does not point like an abscess and no pain sensation present.

Abscess

Tumor in animals does not point like an abscess. Exploratory puncture with needle may reveal pus in case of Abscess.

Cyst

Cyst is slow in development as compared to an abscess. Soft and fluctuates uniformly, but not hard at periphery. No inflammatory symptoms. No pain sensation in case of cyst.