Oncology Mammary Tumours

Question 1

Mammary Tumours DDX

Answer 1

Lipomas
MCT
Soft Tissue Sarcoma
Mastits (systemic signs)(lactating bitches post partum)(hot red and painful)(use cephalosporins for E.Coli)
Abcess (systemic signs in lactating bitch, painful)(surgically drain)

Question 2

Flank Mass

Answer 2

Lipoma
MCT
Soft Tissue Sarcoma

Question 3

DIagnostic Tests

Answer 3

FNA ALL MASSES
Serum and bloodchem (stress leukogram?)
urinalysis
Thoracis Radiographs (x3)
Abdominal US (look at internal LNs)
EXCISIONAL Biopsy + Histopathology + CHEMO

Question 4

Cat and Dog mammary tumours

Answer 4

DOg- 50:50 benign:malignant - carncinomas common in CAUDAL GLANDS

Cats - 90% malignant - adenocarcinomas common (mulitple masses/ulcerated)

Question 5

Staging Mammary Tumours

Answer 5

1. Vascular and Lymphatic invasion = poor prognosis
2. Anaplastic Carcinomas/Sarcomas = poor prognosis (less differentiation)
3. Inflammatory Carcinomas (present as diffuse swelling/oedoma/pain/systemic signs)
4. size
5. LN involvement (palpation and abdominal US)
6. Presence of distant metastasis

T=Tumour size (<3, 3-5, >5cm)
N0= No regional LN N1= metastasised to regional LN
M0= No distant metastasis M1= Distant metastasis

Question 6

Surgical Standard of care for mammary tumours

Answer 6

1. SHOULD HAVE SPAYED BEFORE 1st/2nd SEASON
2. CATS SPAY BEFORE 6 MONTHS
   as later gives no protective effect

CLEAN SURGERY unless its an INFLAMMATORY CARCINOMA

DOGS- excise all tumour using simplest surgery( 2-3cm margins)+ FAC chemo
CATS- unilateral mastectomy or staged bilateral mastectomy allows better wound reconstruction and healing (2nd intention healing)

FNA of metastatic sites every 3 months post op

Drains else can get SEROMAS
HINDLIMB OEDEMA will resolve itself

Question 7

Systemic TX for Mammary tumours

Answer 7

Good for high grade tumours, metastasised, poor prognosis, Metronomic therapy for resistant tumours

Dogs- (FAC)5FU- Cyclophosphamide- Doxarubicin
Cats- Cyclophosphamide and Doxorubicin

Question 8

Cause of Mammary Tumours

Answer 8

1Hormonal influence- oestrogen and prgesterone receptors which metastatic tumours lose
2, Over and underexpression of genes (BCRA1/2)

Question 9

Risk Factors for developing Mammary Tumours

Answer 9

1. increasing age
   2 obesity
2. already having a benign mammary tumour
   4 not spayed or spayed late (after 2.5 years)

Question 10

POST-OP CARE/COMPLICATIONS

Answer 10

<3- will recur 30%
>3cm- will recur 85%
SARCOMAS the WORST 
poorly differentiated = 90% mortaltity
LN inlvolvement increases mortalithy 
Fixation
Ulceration

RECEPTOR PRESENCE GIVES BETTER PROGNOSIS

NOT PROGNOSTIC- site of tumour/type of surgery/no.of tumours/performing OHE at tumour excision