Lesson 76 Neoplasia and developmental disorders

Granulosa cell tumor (GCT)

ovary, hormone secreting, unilateral

common in mares, hormone secreting

signs: anestrus, nymphomanias, stallion-like behavior from testosterone production

Dysgerminoma

ovary (germ cells)

rare, malignant, can metastasize

teratoma

ovary(germ cells). benign

can contain hair, teeth, bone

leiomyoma

uterus, vagina

smooth muscle tumor, benign

common in bitches. may cause dystocia(slow labor) or infertility

leiomyosarcoma

uterus

malignant smooth muscle tumor, invasive and metastatic

endometrial adenocarcinoma

uterus

malignant epithelial tumor

common in cows rabbits

squamous cell carcinoma

vulva, cervix

malignant epithelial tumor

linked to UV exposure in pale skin

common in mares and cows

Tranmissible venereal tumor

vagina, vulva

trasnmission venereal. common in dogs

cauliflower like masses can resolve with host immunity or chemo therapy

Melanoma

vulva, perineal region

common in older grey horses

can be benign or malignant

seminoma

testis (germ cell)

common in cryptorchid dogs

benign s

sertoli cell tumor

testis (sex cord stromal)

produces estrogen→ feminization, alopecia, gyenecomastia, bone marrow suppression

common in intact males

interstitial (Leydig) cell tumor

testis

common in older dogs

benign. secrete testosterone→ prostatic hyperplasiawhat

what do sertoli and leydig cells normally do

sertoli(stim by FSH)→ spermatogenesis

leydig(stim by LH)→ testosterone

what do granulosa and theca cells normally do

Theca (stim by LH)→ androgen ex. testosterone

granulosa (stim by FSH)→ estrogen

prostatic adenocarcinoma

prostate gland

aggressive, malignant→ can metastasize to bone and lungs

common in older nuetered dogs

squamous cell carcinoma in males

penis prepuce

common in horses, cattle

locally invasive and ulcerative

transmissible venereal tumor in male

penis prepuce

common in dogs

transmission via sex. able to resolve vincristine chemotherapypapi

papilloma

penis prepuce

common in young bulls

benign epithelial tumor, viralpe

perianal gland adenoma

perianal region

common in intact males

androgen dependent, can regress with castration

benign

What gene presence determine if fetus become male

SRY gene

What is the two ducts present in early fetus development before sex is differentiated

mesonephric (wolffian) duct

paramesonephric (mullerian) duct

What does SRY gene expression do

created testis determining factor (TDF)

sertoli cell secrete anti mullerian hormone→ mullerian ducts regress

leydig cells produce testosterone

What happens in fetus with no SRY expression

no TDF made so both ducts are retained and primitive gonads develop into ovaries

Repro tract development

white heifer disease

genetic link to white coat. common in shorthorn cattle

failure or paramesonephric ducts to develop→ results in uterus unicornis(only one horn develops)

-persisitent hymen, horns fill with mucus

but normal sized ovaries and active

freemartinism

female born as co-twin with a male→ female is exposed to testosterone and AMH→ resulting in chimeras, incomplete development paramesonephric ducts(horn) and ovaries

-female will act bullish

-most common in cows

Signs of freemartinism

anestrus, large clitoris, small ovaries, increase distance b/w anus and vulva, lots of pubes

polled intersec syndrome

common in dairy goats

-male psuedohermaphodites (male but look female)

-female at birth but develop male characteristics

• ex. larger, aggressive, buck odor, and erect hairs on neck. small teats and enlarged clitoris

gynecomastia

common in dairy goats and polled animals

“milking buck syndrome”

pituitary tumor→ increased prolactin and estrogen→ boobies

normal libido and fertility but not preferred for breeding

Sperm granuloma

common in bucks, and heritable

abnormal formation of epididymis head=sperm buildup and ductule rupturing→ inflammation and granuloma ± calcification→ testicular degeneration

signs: firm swelling at head of epididymis or small atrophic testis

persistent frenulum (attaches penis to prepuce)

normal in prepubertal bulls but should disappear postpubertal

-heritable

-results deviation of penis

sex reversal disorders

chromosomal sex does not match with gonadal or phenotypic sex

vaginal stricture

scar tissue → narrowed vaginal canal.

vaginal septum

divides lumen in vagina, basically extra wall

significane of vaginal septum and vaginal sticture

interference with breeding, making it painful or hard birth

63, xo gonadal dysgenesis

disorder of sexual development in mares

signs: small ovaries, infantile organs

cryptorcchism

failure one or both testis to descend into scrotum

common horses, pigs and dogs

hormones production is normal but spermatogenesis is affected

retained testes prone to spermatic cord torsion and testicular neoplasia

which tumors are more common in female repro system

ovarian tumors

which tumors are extremely rare in female repro system

oviductal and cervical tumors

What is the most common ovarian tumor

granulosa cell tumor (GCT)

Granulosa cell tumor in mares

unilateral, slow growing, benign→ destroy ovary architecture

-secrete hormone-estrogen, AMH, testosterone, inhibin→ atrophy of contralateral ovary

signs: aggression, stallion like behavior, masculine muscle development, irregular estrous cycle, anestrus

GCT hormones

AMH increased in 98% of mares

Inhibin increased in 80% of mares

testosterone increased in 48% of mares

GCT in dogs and cats

most common in older dogs/cats. more malignant in cats

still functional, secretes hormones (E2 and PG)

estrus like signs

-persistance of estrogen can lead to hyperestrogenism

-persistence of progesterone can lead to cystic edometrial hyperplasia and pyometra

hyperestrogenism

alopecia, bone marrow suppression

which hormone is best used to diagnose granulose cell tumor

AMH

Teratoma

germ cell-hair or bone can be found

not hormonally active, unilateral

contralateral ovary is fine

benign→ no need to remove

cystadenoma

enlarged, absence of ovulation fossa (dent where ovulation occurs)

looks honeycomb on U/S from multiple small cysts

contralateral ovary is normal

slow growing but surgery not urgent. no metastasis

Dysgerminoma

germ cell tumor, enlarged and solid, no ovulation fossa

massive echogenic structure on U/S

unilateral and hormonally inactive, slow growing

contralateral ovary is active

potential metastasis, surgery required

uterine tumors

not common

benign: leiomyoma, fibroma, fibroleiomyoma

malignant: leimyosarcoma, rhabdomyosarcoma, lymphosarcoma, adenosarcoma

Vaginal tumors

common in older dogs

benign but space occupying→ vaginal discharge, tenesmus(urge to poo), stranguria, hemorrhage, vaginal irritation

can be hormone dependent

ex. TVT

TVT-transmissible venereal tumor

affect any age bitches

transmission: coitus(mating)

round cell tumor

signs: cauliflower like growth on vaginal mucosal and serosanguinous discharge

which tumor is more common in male repro system

testicular tumors-most common is sertoli cell tumor

sertoli cell tumor

most common testis neoplasia

low malignancy, one side enlarged and other may be atrophic

signs: feminizing paraneoplastic syndrome from estrogen secretion→ pancytopenia, nonregenerative anemia, pale, bilateral alopecia, hyperpigmentation, gynecomastia, pendulous preputial sheath

seiminoma

tumor of testes germ cell

low malignancy, paraneoplastic syndrome (functional symptoms not physical space invading)

interstitial/Leydig cell tumor

most common in scrotal testes

small, discrete hard to detect clinically

low malignany

paraneoplastic syndrome ex. hyperestrogenism, hypertestosteronism, prostate disease, perianeal adenoma, hyperplasia or hernia

what clinical signs are most commonly associated with sertoli cell tumors in dogs

alopecia and feminization

Spermatic cord torsion

common in retained and neoplastic testes

-360 degress: anorexia, vomiting, abdominal pain, lethargy pyrexia, scrotal swelling

-180 degrees: subclinical and self correcting

prostatic metaplasia

secondary to estrogenic stimulation

low grade inflammation

dx: squamous cells in cytology

can lead to cysts, prostatis/ abscess

castration recommended

prostatic neoplasia

ex. malignant adenocarcinoma most common and most common in castrated dogs

high rate metastasis

signs:

- GIT-tenesmus, constipation

-urinary: stranguria, hematuria

-weightloss, pain, ataxia

what prostatic condition is more common in neutered dogs

prostatic neoplasia

fibropapilloma

common in young bulls

signs: hemorrhage, ulceration, impaired libido, phimosis (unable protrude) or paraphimbosis (unable to draw back)

prognosis: may return to breeding after treating

Most common testicular tumor in cryptoorchid dogs

sertoli cell tumor