|
|
(7 intermediate revisions by the same user not shown) |
Line 1: |
Line 1: |
− | ==Introduction== | + | {{frontpage |
| + | |pagetitle =Intestines - Proliferative Pathology |
| + | |pagebody = |
| + | |contenttitle =Content |
| + | |contentbody =<big><b> |
| | | |
− | * Tumours may develop from any of the components of the intestinal wall.
| + | <categorytree mode=pages>Intestines - Proliferative Pathology</categorytree> |
− | ** May be of either a benign or malignant variation.
| |
− | * Tumours have a wide range of effects on intestinal funtion.
| |
− | *# Many malignant tumours cause intestinal obstruction at their point of origin.
| |
− | *#* E.g. intestinal adenocarcinomas, solitary lymphomas.
| |
− | *#* Onset is often gradual (unlike most foreign bodies)
| |
− | *#* Benign tumours can also cause obstruction, but this is most likely if they
| |
− | *#** Protrude into the lumen
| |
− | *#** Are located at a compressible site, e.g. within the pelvis, at the duodenal flexure.
| |
− | *# Tumours that diffusely infiltrate the mucosa cause diahorrea due to malabsorption and development of a protein losing enteropathy.
| |
− | *#* E.g. diffuse alimentary lymphoma.
| |
− | *# Benign or malignant tumours can result in mucosal erosion or ulceration.
| |
− | *#* Blood is lost, causing haemorrhagic anaemia.
| |
− | *#** Prolonged bleeding can cause iron deficiency anaemia.
| |
− | *#* Extensive tumour necrosis may occur due to rapid growth or secondary infection.
| |
− | *#** This can cause gradual or sudden perforation and peritonitis.
| |
| | | |
| + | </b></big> |
| + | |logo =path-logo.png |
| + | }} |
| | | |
| | | |
| | | |
− | == Adenocarcinoma ==
| + | [[Category:Intestines,_Small_and_Large_-_Pathology]] |
− | | |
− | * An '''intestinal adenocarcinoma''' is a malignancy of epithelial cells from the intestinal mucosa.
| |
− | * Found in both the [[Small Intestine - Anatomy & Physiology|small]] and [[Large Intestine - Anatomy & Physiology|large intestines]]
| |
− | ** Common in the canine [[Rectum - Anatomy & Physiology|rectum]].
| |
− | * Species affected:
| |
− | ** Fairly common in dog and cat.
| |
− | ** Seen related to bracken ingestion in the older sheep.
| |
− | ** Occasionally occur in horses.
| |
− | * These tumours usually grow away from the mucosa, down through the muscularis mucosae and into the submucosa, muscular layers and the serosa.
| |
− | ** They may, however, project into the lumen.
| |
− | * Intestinal adeocarcinomas may take an annular form.
| |
− | ** This may result in stenosis of lumen
| |
− | *** Muscle proximal to the lesion becomes hypertrophied and dilated.
| |
− | * Spread may be
| |
− | *# Via the lympahtics.
| |
− | *#* To the lymph nodes, lung and [[Liver - Anatomy & Physiology|liver]].
| |
− | *# Transcoelomic spread
| |
− | *#* Small, white plaques on serosa and adjacent tissues e.g. diaphragm.
| |
− | | |
− | == Lymphoma ==
| |
− | | |
− | * Lymphoma occurs in both the small and [[Large Intestine - Anatomy & Physiology|large intestine]]s.
| |
− | * Is a relatively common neoplasm of the cat and dog.
| |
− | * Causes a diffuse spread of neoplastic lymphocytes through the mucosa and the rest of the wall.
| |
− | ** Leads to malabsorption and therefore [[Diarrhoea|diarrhoea]] and the development of a protein losing enteropathy.
| |
− | | |
− | == Mast cell tumours ==
| |
− | == Intestinal stromal tumours ==
| |
− | | |
− | ==Tumours of the Perianal Area==
| |
− | | |
− | | |
− | ===Hepatoid Gland Tumours (Perianal Adenomas)===
| |
− | [[Image:normal perianal gland.jpg|thumb|right|100px|Perianal gland- normal (Courtesy of Bristol BioMed Image Archive)]] * Affect the dog.
| |
− | * Arise from the solid, modified sebaceous circumanal glands.
| |
− | * Common in ageing entire males. [[Image:perianal gland adenoma histopath.jpg|thumb|100px|Perianal gland- adenoma (Courtesy of Bristol BioMed Image Archive)]]
| |
− | | |
− | * Lesions range from hyperplasia to true adenomas (benign).
| |
− | ** These low grade lesions are under hormonal control.
| |
− | *** Castration/ administation of oestrogens or anti-androgens causes reduction in size.[[Image:perianal gland adenoma.jpg|thumb|right|100px|Perianal adenoma- gross appearance (Courtesy of Bristol BioMed Image Archive)]]
| |
− | * Occasionally hepatoid carcinomas (malignant) arise in affected males
| |
− | ** Outwith hormonal control.
| |
− | * Hepatoid gland tumours occur rarely in bitches.
| |
− | ** Are commonly malignant.
| |
− | * Hepatoid glands are also found at the tail head, prepuce and occasionally other skin sites.
| |
− | ** Hepatoid tumours can also arise in these areas.
| |
− | | |
− | ===Adenocarcinomas of the Glands of the Anal Sac (Apocrine Glands)===
| |
− | | |
− | * Apocrine glands are the true anal glands- not to be confused with the anal sacs or the perianal glands.
| |
− | * Much less common than intestinal adenocarcinoma.
| |
− | * Commoner in bitches than dogs.
| |
− | * Can be bilateral.
| |
− | * Consequences:
| |
− | ** May cause local problems.
| |
− | ** May metastasise.
| |
− | ** Often secrete a parahormone-like substance to cause paraneoplastic syndrome.
| |
− | *** This can arise even when the primary tumour is very small.
| |
− | *** Results in bone resorption and hypercalcaemia,
| |
− | **** In turn can cause renal failure. which in turn can cause renal failure.[[Category:Intestines,_Small_and_Large_-_Pathology]]
| |