solid tumours 1 - mammary

When to neuter to dec risk

Before first oestrus > before second oestrus > before third oestrus

No dec if neuter after 2nd season

Hormones leading to inc risk

Progestin, oestrogen

Risk factors

Neutering after 1st oestrus

Progestin, oestrogen

Obesity

>9yrs

Poodle, chihuahua, daschund, Maltese, cocker, Yorkshire terrier, Siamese

% benign in dogs

50%

Dx option to exclude ddx

FNA

Ddx og mammary tumours

Mastitis, lipoma, MCT, hyperplasia

Dx options

FNA

Excisional biopsy

What to assess pre sx

CE - tumour size, attachment, LN

Local staging - local LN

Distant staging - rx, CT, US, bone

Sx options

Mastectomy (single / regional)

Unilateral chain mastectomy (intact)

Sx margins

Mobile lesion = whole gland

Fixed lesion = 2cm

Prognostic factors

Sarcoma worse than carcinoma

Mitotic rate

Grade

Hormone receptors

Dec tissue heterogeneity

Canine infl carcinoma - CS

Painful

Whole gland affected

Erythema

Symmetrical

Canine infl carcinoma - Dx

FNA

Canine infl carcinoma - Tx

Palliative

Most important prognostic factors for mammary tumours

Size

Malignancy

Metastasis

Fixed/ mobile

Ki67

Sarcoma vs carcinoma

Mitotic rate

Feline mammary tumours - ddx

Fibroepithelial hyperplasia

Feline mammary tumours - % malignant

85-95%

Feline mammary tumours - Prognostic factors

Size (2cm)

LN metastasis

Breed (DSH better)

Feline mammary tumours - Which LN to check

Inguinal, axillary

Feline mammary tumours - Tx

Chain mastectomy

Inguinal/ axillary LN removal

OHE during mammary tumour excision - in dogs

Dec chances of new ones if benign

OHE during mammary tumour excision - in cats

Unclear benefits

Chemo options in dogs

Doxorubicin

5-FU

Cyclophosphamide

Chemo options in cats

Doxorubicin

Cyclophosphamide

Cat with 1.5 well circumscribed mass → approach

Cytology