Mammary Neoplasia - Revision history

Bara at 12:16, 9 August 2012

2012-08-09T12:16:40Z

Bara: /* Prevention */

2011-08-15T22:15:09Z

Prevention

Bara at 22:14, 15 August 2011

2011-08-15T22:14:48Z

HelenD at 14:03, 6 August 2011

2011-08-06T14:03:13Z

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Bara: Created page with "===Mammary Neoplasia=== Mammary neoplasms occur but are rare in the large domestic/production animals. Benign and malignant mammary tumours are most commonly encountered in bitch..."

2011-04-12T20:09:36Z

Created page with "===Mammary Neoplasia=== Mammary neoplasms occur but are rare in the large domestic/production animals. Benign and malignant mammary tumours are most commonly encountered in bitch..."

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===Mammary Neoplasia===
Mammary neoplasms occur but are rare in the large domestic/production animals. Benign and malignant mammary tumours are most commonly encountered in bitches and queens.
'''Mammary neoplasia in bitches'''
*Neoplasia is associated with increasing age. Benign/dysplasia can occur in young bitches.
*Multiple tumours in one or more mammary glands occur. Multiple tumours may be different i.e. not all benign or malignant.
*Benign and malignant tumours may be present in the same gland.
*About 60% of benign tumours are of mixed histological type.
*It is not possible to delineate benign or malignant nature on clinical grounds alone although clinically non invasive tumours tend to be benign. Tumour size is not a reliable criterion, but those larger than 5cm diameter tend to be worse.
*Speed of growth may indicate a malignant tumour but some hormonally - dependent benign tumours can grow quickly.
*Invasion is the most important criteria of malignancy. Many of those designated histologically as a carcinoma are not invasive and do not metastasise. Solid and anaplastic carcinomas have a poor prognosis; many ductular, papillary or acinar types do not metastasise.
*Tumours may contain neoplastic elements derived from both epithelial and myoepithelial and/or stromal cells. They are known as complex tumours; they are mostly benign but malignant types can occur.
*Some tumours contain cartilage and or bone and are called mixed tumours.
*Malignant tumours are carcinomas or sarcomas. Carcinomas may be aggressively malignant, metastasising to regional lymph nodes, lungs, liver, spleen, kidney and other sites. Survival from diagnosis is 3-24months

<br>'''Mammary neoplasia in cats'''
*Much less common in cats but 80% are aggressive carcinomas. Many cats have ulcerated primaries and metastatic disease already present at initial presentation.
* There is little evidence that ovariohysterectomy has a protective effect, as it does in the dog.
*Benign tumours are rare.
*Mammary fibroepithelial hyperplasia may occur in young and female cats as a spontaneous condition or, more often, associated with a progestagen treatment.
*Carcinomas metastasise to regional lymph nodes, lungs, liver, kidneys, and other sites.
*Prognosis is always very guarded to poor over the long term. The range of survival times are very wide unless the tumour is greater than 3cm diameter (27cm3)

<Br>Information by permission of Professor RW Else

[[Category:Neoplasia]]
[[Category:Mammary Gland - Pathology]]
[[Category:To Do - Reproductive]]

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 ==Introduction==
 Mammary tumours are '''common in female dogs''', with '''35-60% being malignant'''. They occur in male dogs but are rare and likely to be malignant.
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 {{review}}
 [[Category:Expert Review - Small Animal]]

← Older revision		Revision as of 22:15, 15 August 2011
Line 98:		Line 98:

	In cats the relative risk if spayed '''before 1 year''' is 0.6% compared to intact cats.		In cats the relative risk if spayed '''before 1 year''' is 0.6% compared to intact cats.
		+
		+

	<big><b>Also see [[Mammary Neoplasia - Rat]]</b></big>		<big><b>Also see [[Mammary Neoplasia - Rat]]</b></big>

@@ Line 13: / Line 13: @@
 Possible mammary tumours include:
-:'''Benign''': Adenoma/fibroadenoma
+:'''Benign''': [[adenoma]]/fibroadenoma, benign mesenchymal tumour, benign mixed tumour
-::Benign mesenchymal tumour
+==Clinical Presentation==
 The animal will present with a history of the owner noticing a '''lump''', or it may be discovered during routing physical examination. It is rare for the animal to present with signs referable to metastases such as coughing or lameness.
@@ Line 43: / Line 32: @@
 ==Diagnosis==
-Mammary neoplasms cannot be diagnosed visually.
+Mammary neoplasms cannot be diagnosed visually. The aim is to obtain a diagnosis and to stage the disease using the '''TNM system''':
-The aim is to obtain a diagnosis and to stage the disease using the '''TNM system''':
+'''Haematology and biochemistry''' should be performed to make sure geriatric patients are safe to anaesthetise.
-<u>Tumour size</u>: T1 <3cm, T2 3-5cm, T3 >5cm
+'''Radiography''' of the thorax and abdomen to check for distant metastases is recommended.
 '''Fine needle aspiration and cytological analysis''' of the mass is an essential tool: it may reveal cells with criteria for malignancy, with distinct nucleoli, high nuclear-cytoplasmic ratio and moderate anisocytosis and anisokaryosis.
@@ Line 68: / Line 50: @@
 '''Immunohistochemistry''' can be performed to determine the presence of hormone receptors in the tumour, but this is an expensive test which does not really alter the treatment plan.
 Other diseases which may '''mimic mammary masses''' and which should be ruled out include:
@@ Line 93: / Line 74: @@
 ==Prognosis==
 In '''dogs''', prognostic factors include:
+:'''Tumour size''': <3cm 30% recurrence, >3cm 85% recurrence
-'''Tumour size''': <3cm 30% recurrence, >3cm 85% recurrence
+:'''Histologic type''': sarcomas are worse than carcinomas or mixed types
+:'''Grade/differentiation''': 90% mortality at 2 years if the cells are poorly differentiated, 24% mortality at 2 years if the cells are well differentiated.
-'''Histologic type''': sarcomas are worse than carcinomas or mixed types
+:'''Lymph node involvement''': if present, there is 80% recurrence.
+:'''Distant metastases''' have a poorer prognosis
-'''Grade/differentiation''': 90% mortality at 2 years if the cells are poorly differentiated, 24% mortality at 2 years if the cells are well differentiated.
+:'''Presence of progesterone/oestrogen receptors''' holds a better prognosis.
 There is no evidence that site or number of tumours is a prognostic indicator.
 '''Inflammatory carcinomas''' have a grave prognosis with <4 weeks survival time. '''Malignant tumours''' incompletely excised hold a 75% mortality within the year. Dogs with malignant tumours completely excised and with no evidence of metastases are expected to live 1-2 years. Complete excision of '''benign tumours''' is curative.
 In '''cats''', prognostic factors include:
+:'''Tumour size''': >3cm medial survival time <6 months, <2cm median survival time 3 years.
-'''Tumour size''': >3cm medial survival time <6 months, <2cm median survival time 3 years.
+:'''Extent of surgery''': there is 66% recurrence if local surgery rather than radical mastectomy is performed
+:'''Histologic grading''': well differentiated tumours with no evidence of lymphatic invasion have a better prognosis.
 The overall median survival time is <1 year and the disease hold a '''poor prognosis overall in cats'''.
@@ Line 129: / Line 98: @@
 In cats the relative risk if spayed '''before 1 year''' is 0.6% compared to intact cats.
 ==References==
@@ Line 140: / Line 111: @@
-[[Category:To Do - Helen]]
+{{review}}
 [[Category:Neoplasia]]
 [[Category:Mammary Gland - Pathology]]
-[[Category:To Do - Reproductive]]
+[[Category:Reproductive Diseases - Dog]]