Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Reproduction > Small animal mammary disease > Flashcards

Small animal mammary disease Flashcards

1
Q

What is the malignancy rate of mammary tumours in bitches?

A

35-50% malignant (assume all are malignant); of these, about 50% are likely to metastasise

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Breed predisposition - mammary tumours

A 
Poodles
Spaniels
English Setters
Pointers
Maltese
Yorkshire terriers
Dachsunds
Dobermans
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Outline mammary tumours in male dogss

A

Do occur
Rare (<1%)
Likely to be malignant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Outline mammary tumours in cats?

A

Less common in cats that bitches

90% are malignant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Common site of mammary tumour metastasis

A

Common - LNs and lung

Other sites - liver, kidney, bone, heat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Cause - mammary tumours

A
  • Hormonal influence likely - 90% benign tumours and 50% malingnant canine tumours have E2 and P4 receptors
  • Metastatic mammary tumours tend to lose both of these types of receptor
  • Some feline tumours contain P4-R, rarely E2-R
  • Other - over/under expression of genes, adhesion molecules, VEGF, COX-2, other factors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Risk factors - mammary tumours - 5

A
  • Increasing age (>9.5 years)
  • Obese early in life (<1 year, esp if fed home-cooked red mince)
  • Progestagen treatment (increases risk of benign in dogs and malignant in cats)
  • Dogs with benign mammary tumours have a 3-fold risk of developing malignant mammary tumours
  • Intact status or bitches spayed after 2.5 years
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Outline relative risk of mamary tumours in BITCHES after spaying after different seasons

A 
RELATIVE RISK:
Spayed before first season: 0.05%
After 1st season: 8%
After 2nd season: 26%
After 3rd season: no protective effect

This is a 1969 study, recent systematic review found limited evidence to support this.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Outline relative risk of mamary tumours in QUEENS after spaying after different seasons

A

RELATIVE RISK:
spayed before 6 months: 9%
6-12 months: 14%
>1 year: no protective effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

List some clinical signs that may be referable to metastases

A

constipation, lameness, coughing etc.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What should you check when you find a mammary mass?

A 
Size
Single or multiple
One/both mammary chains
Canine - most common in caudal glands
Moveable or fixed
\+/- ulcerated
Also palpate axillary and inguinal LNs
Rectal exam - enlarged sublumbar LNs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Incidence of inflammatory carcinoma

A

Uncommon (8% mammary tumours)
Agrressive
Presents as diffuse swelling rather than discrete mass
Often massive oedema, erythema, pain, progresses rapidly, highly metastatic, systemically ill

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Outline typical features of feline mammary masses

A

often not a discrete mass OR there are multiple masses (>50%), and they are more often (25%) ulcerated.
>80% are adenocarcinomas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

List benign mammary tumour types

A

Adenoma/firboadenoma
Benign mesenchymal tumour
Benign mixed tumour

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

List some malignant mammary tumour types

A 
Carcinoma - solid, tubular, papillary, anaplastic/inflammatory 
Sarcoma
Carcinosarcoma
Adenocarcinoma
Sarcoma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

List DDx for enlarged or inflammed mammary glands - 5

A 
Mastitis
Galactostasis
Galactorrhea
Mammary hyperplasia
Skin=cutaneous/subcutaneous tumours
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

When might mastitis occur?

A

Postpartum bitches

Occasionally after oestrous or false pregnancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Treatment - bitch mastitis

A

IV fluid therapy if dehydrated
IV AB therapy until resolved (usually 7 days)
Cephalosporins - good empirical choice - BS of activity against likely bacteria (E. coli) and are likely to reach effective concentrations in infected glands
Surgically rain mammary abscesses
Puppies can continue to nurse if bitch accepts and enough nutrition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Define galactostasis

A

accumulation and stasis of milk within mammary gland of nursing bitches (occasionally false pregnancy)

Secretions: not infected
Self-resolving at weaning or peak lactation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Define galactorrhea

A

Lactation that is NOT associated with pregnancy and parturition (i.e. during false pregnancy)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Pathophysiology of galactorrhea

A

Results from increased PRL secretion which is stimulated by falling P4 levels in late dioestrous.
Usually self-limiting, no Tx required
Withholding food (24h) followed by gradual return to normal quantities helps reduce lactation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Mammary hyperplasia - when and what?

A 
Rapid abnormal growth of mammary tissue that is most commonly seen in YOUNG, entire female cats 2-4 weeks after oestrous due to elevated P4 concentrations (irrespective of whether they have become pregnant or not).
Benign
Usually resolves once P4 declines
Biopsy - to rule out other DDx
Neutering - prevents recurrence
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How are mammary neoplasias staged?

A

T = Tumour size = T1< 3cm, T2 3-5cm, T3 = >5cm

N = Regional Lymph node = N0 no metastasis, N1 = metastasis (on histopathology)

M = Distant metastasis = M0 not present, M1 = present

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

List diagnostic tests for enlarged mammary glands

A 
Haematology and biochemistry
Radiography
Ultrasound
FN aspiration
Coagulogram
Surgical biopsy
IHC
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Why run haematology and biochemistry?

A

to make sure geriatric patients are safe to anaesthetise - kidneys and liver most important

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What radiography?

A

chest and abdomen - check for lung and sublumbar LN metastases which are present in 25-50% dogs with malignant tumours at time of diagnosis.

CT = more sensitive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What should you check on ultrasound?

A

liver, spleen, sublumbar and inguinal LNs for enlargement

28
Q

Why perform FNA?

A

differentiate benign/malignant mammary masses as uncertain on cytology alone.
Useful to differentiate mastitis from inflammatory carcinoma and for investigating enlarged LNs (U/S guided)

29
Q

Why perform a coagulogram?

A

Perform if suspect inflammatory carcinoma as these dogs are at high risk for developing DIC

30
Q

Outline surgical biopsies for mammary masses

A 
Usually excisional (i.e. therapeutic). 
Incisional - indicated for inflammatory carcinoma or any other tumour which is inoperable. Sends ALL tumours for pathology and record the site of each one.
31
Q

Why run IHC?

A

Determines prescence of hormone-Rs in tumour - expensive and not usually needed to make the treatment plan so not routine.

32
Q

Outline a possible chemotherapy protocol for canine mammary tumours

A

Cyclophosphamide and 5-FU
Stage 3 or 4 disease
Increases survival - 24 months versus only surgery (6 months)

33
Q

Use of radiotherapy for canine mammary tumour

A

Limited use in dogs

34
Q

What is tamoxifen

A

A drug used in human breast cancer patients which binds to oestrogen receptors. Tried in dogs but not very effective and resulted in high incidence of oestrogenic side effects (bleeding, stump pyometra). Not all tumours have oestrogen receptors and other hormones and growth factors are also implicated in tumour growth.

35
Q

When is surgical treatment of mammary tumours not indicated?

A

Inflammatory carcinoma

Where distant metastases have already been identified.

36
Q

How many nipples do bitches and queens have?

A

BITCH: 5 pairs of mammary glands
QUEEN: 4 pairs of mammary glands

37
Q

Describe the brief structure of mammary glands

A

Mammary glands are compound, tubuloalveolar, apocrine glands

38
Q

Outline vascular supply to mammary glands

A

Caudal superficial epigastric to caudal glands
Cranial superficial epigastric to cranial glands
Branches of internal thoracic too.

39
Q

Outline mammary gland LN drainage

A

DOGS: glands 1,2 –> axillary LN, gland 3 –> either direction, usually axillary LN, glands 4,5 –> inguinal LN, also variable lymphatic connections between glands 3+4 and across the midline

CATS: glands 1,2 –> axillary LN, glands 3,4 –> inguinal LN

N.b. if you remove gland 5, expect to remove the inguinal LN

40
Q

List surgical guidelines for mammary tumour removal

A
  • Excise tumour - 2-3cm margins
  • Excise underlying abdominl wall fascia if tumour attached
  • If large or extensively attached, may need full thickness body wall excision + surgical reconstruction
  • Ligate branches of cr and or cd superficial epigastric vessels as they are encountered
  • If extensive dead space, place a closed-suction drain in the wound
  • sterile towel clips very useful for bringing together large skin wound for you to place subdermal sutures
  • If margins are incomplete, wide re-excision should be considered
41
Q

List general surgical recommendations - mammary tumour removal - cats

A

Unilateral mastectomy is the minimum recommendation or risk 66% local recurrence rate

42
Q

List general surgical recommendations - mammary tumour removal - dogs

A

Excise all tumour using the simplest surgery needed to achieve this. Incomplete surgery or debulking isn’t acceptable. Final choice of surgery may be based on tumour size, location and number.

43
Q

What is a lumpectomy?

A

= excision of a mass with a surrounding margin of grossly normal tissue.
Use when mass is small (<0.5cm), encapsulated, non-invasive and at the periphery of the gland.
May get leakage of milk or lymph leading to post-op inflammation.

44
Q

What is a simple mastectomy?

A

= excision of the entire gland containing the tumour with 2cm margins.
used when the tumour is >1cm, in the centre of the gland or involving the majority of it, or adherent to adjacent tissues.
Less risk of milk leakage

45
Q

What are the surgical options for tumour removal? 5

A 
Lumpectomy
Simple mastectomy
Regional mastectomy
Unilateral mastectomy
Bilateral mastectomy
46
Q

What is a regional mastectomy?

A

= excision of involved and adjacent glands with 2cm margins

  • Used for excision of multiple tumours in adjacent glands or if a mass is between 2 glands
  • The caudal 2 glands are often excised together along with the inguinal LN
  • The axillary LN is not excised with the cranial glands unless specifically indicated
47
Q

What is a unilateral mastectomy?

A

= excision of tumours in the third gland or multiple tumours in one mammary chain is usually best treated by excision of all5 mammary glands on onse site as a unit (including excision of the ipsilateral inguinal LN)

  • Often quicker/easier and reduces surgical trauma compared to multiple separate mastectomies
  • Careful, tension-free closure essential to prevent dehisence
48
Q

What is a bilateral mastectomy?

A
  • Reserved for when there are numerou smasses in both mammary chains
  • Skin closure is difficult/impossible if performed bilaterally in one surgery
  • Risk of wound breakdown is decreased by performing staged unilateral mastectomies several weeks apart.
49
Q

What post-op care is recommended for mastectomies?

A

Pre-emptive multi modal analgesia
Drains - covered and emptied
Abdominal bandage may support extensive wound

50
Q

Complications - mastectomy surgery

A
  • Seromas
  • Wound infection (<5% because it is a clean surgery)
  • Wound dehisence (extensive resections - treat by open wound management until healthy GT forms)
  • HL oedema (disruption to lymphatic drainage of limb)
  • Local recurrence or metastatic spread
51
Q

List prognostic factors in DOGS following mammary tumour removal - 8

A 
Tumour size
Histologic type
Grade/differentiation
Evidence of vascular/lymphatic invasion
LN involvement
Distant metastases
P4/E2-R presence/absence
Fixation to tissue or skin ulceration
52
Q

Define PD

A

poorly differentiated (tumour)

53
Q

Define WD

A

well differentiated (tumour)

54
Q

List prognostic factors in CATS following mammary tumour removal - 8

A

tumour size
extent of surgery
histologic grading

55
Q

What factors are not prognostic? 4

A

Site of tumour
Type of surgery in dogs (so long as complete)
Number of tumours
Performing OHE at time of tumour excision (controversial)

56
Q 
What are the survival times in dogs of:
inflammatory carcinomas
malignant, incompletely excised
malignant, complete excision, no mets.
malignant, complete excision, mets
benign
A

inflammatory carcinomas = 30 days
malignant, incompletely excised = 75% mortality <1 year
malignant, complete excision, no mets. = 1-2 years
malignant, complete excision, mets = 5 months
benign = complete excision is curative

57
Q

What is the overall median survival time in cats for a malignant mammary tumour?

A

< 1 year

58
Q

Prevention - mammary neoplasia - cat/dog

A

Early spaying (almost completely preventable)

OVH at same time as mastectomy is controversial but should be seriously considered as it reduced risk of new tumours by about 50% when performed in dogs with benign mammary tumours. Also prevents pyometra.

No evidence that concurrent OHE reduces recurrence of mammary tumours in cats.

59
Q

Outline prognosis based on dog tumour size

A

< 3cm –> 30% recurrence

> 3cm –> 85% recurrence

60
Q

Outline prognosis based on dog histologic type

A

Sarcomas worse than carcinomas or mixed

61
Q

Outline prognosis based on dog grade/differentiation

A

90% mortality at 2 years if PD

24% mortality at 2 years if WD

62
Q

Outline prognosis based on dog LN involvement

A

Present: 80% recurrence

Not present: 20% recurrence

63
Q

Outline prognosis based on dog distant metastases

A

Present –> poorer prognosis

64
Q

Outline prognosis based on dog P4/E2-R presence

A

Better prognosis

65
Q

Outline prognosis based on CAT tumour size

A

> 3cm median survival 15-24 months

3 years

66
Q

Outline prognosis based on CAT extent of surgery

A

66% recurrence if perform local surgery compared to radical mastectomy

67
Q

Outline prognosis based on CAT histologic grading

A

% cats died by 2 year follow up:
42% WD
70% moderately differentiated
100% PD

Reproduction (42 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions