Chapter 28 - Tumors of the Male Reproductive System

Question 1

What is the most common location for tumors in the male reproductive system? What percentage of reproductive tumors do they comprise? Overall prevalence?

Answer 1

Testicles
90%
7% prevalence

Question 2

What are the three most common testicular tumors and from what testicular subsets do they arise?

Answer 2

Sertoli cell tumor - sustentacular cells at seminiferous

Interstitial cell tumor - interstitial cells of Leydig between seminiferous tubules

Seminoma - spermatic germinal epithelium of seminiferous tubules

Question 3

For which tumor is a cryptorchid testicle a risk factor?

Is there a difference between inguinal and abdominal cryptorchidism?

Which testicle is most commonly associated with cryptorchidism?

Answer 3

Sertoli cell tumors and seminomas

Crytporchidism is a risk factor overall, risk is higher with inguinal vs abdominal

Right testicle

Question 4

Up to what percentage of dogs with testicular tumors have more than one type of testicular tumor?

Answer 4

4-20%

Question 5

With what frequency do the different types of testicular tumors occur in dogs within the USA?

Answer 5

Equal frequency

Question 6

In Norway, what breeds are at increased risk for developing testicular tumors? Which ones?

Answer 6

Shelties and Collies have a 5x increased
Shelties - majority (80%) are Sertoli
Collies - majority (70%) mixed Sertoli/seminoma
Norweigan elkhounds - 2x increased risk of seminoma

Question 7

What hormones are produced by the different testicular tumors?

Answer 7

Sertoli - 50% produce estrogen and signs of feminization; 17% if scrotal

Interstitial - rarely testosterone and estrogen

Seminoma - rarely estrogen

Question 8

What tumor is most likely to cause feminization signs?

How can estrogen be measured?

What are the clinical signs?

Answer 8

Sertoli (>50% if cryptorchid and 15% if scrotal)

Estraidol 17-B - usually higher when compared to normal dogs; not all dogs have elevated estraidol

Testosterone/estraidol ratio - usually lower; feminization signs occur secondary to disruptions in this ratio, may be a better

CS: bilateral symmetric alopecia, cutaneous hyperpigmentation, thinning of skin, galactorrhea, gynecomastia, atrophy of prepuce, atrophy of contralateral testicle, squamous prostatic metaplasia, bone marrow suppression

Question 9

What is the metastatic rate of the different types of testicular tumors?

Answer 9

Sertoli - <15%
Interstitial - rare
Seminoma - <15%

Question 10

What is the gross appearance of the different testicular tumors?

Answer 10

Sertoli - firm, lobulated, white or grey, greasy

Seminoma - homogeneous, soft, occasionally lobulated, ivory

Interstitial - soft, expansive, yellow to orange, often contain cysts with serous or serosanguinous fluid

Question 11

Which testicular tumor can sometimes be associated with perianal gland hyperplasia?

Answer 11

Interstitial cell tumor

Question 12

What are early vs late effects of estrogen in BM?

Answer 12

Transient increase in granulopoiesis with peripheral neutrophilia followed by progressive neutropenia, thrombocytopenia, and nonregenerative anemia, resulting in aplastic anemia and pancytopenia

Question 13

What % of dogs with a testicular tumor have a contralateral testicular tumor or a primary tumor elsewhere?

Answer 13

50%

Therefore, COMPLETE STAGING is recommended

Question 14

What is the treatment of choice for testicular tumors?

Answer 14

Bilateral orichectomy and scrotal abalation

Question 15

After castration in dogs with Sertoli cell tumor, when do signs fo feminization resolve?

Prognosis if bone marrow hypoplasia or aplastic anemia present?

Answer 15

1 to 3 months after, unless metastasis is present

BM hypoplasia - guarded
Aplastic anemia - poor

Question 16

How common are feline testicular tumors?

Answer 16

Rare; Sertoli, seminoma, interstitial cell tumor, and teratoma reported

Question 17

What is the prevalence of prostatic tumors in dogs?

Answer 17

<1%

Question 18

What is the most common prostatic tumor found in intact dogs?

Answer 18

Prostatic adenocarcinoma - usually urothelial or ductular in origin, rather than acinar, since they are androgen-independent

Question 19

Where does TCC arise from within the prostate?

Answer 19

Prostatic ducts

Question 20

What is an identified risk factors for prostatic carcinoma development in dogs?

Answer 20

Castration; OR 2.3:4.3

Question 21

What % of dogs with prostatic carcinoma have metastasis at the time of diagnosis and at the time of death?

Which px may be at increased risk for metastasis?

Answer 21

40% at diagnosis; SLLN most commonly
80% at death

Younger dogs

Question 22

What % of canine prostatic carcinoma develops metastatic disease to bone? Most common site?

Answer 22

22 to 42%

Lumbar vertebrae

Question 23

What % of dogs with prostatic carcinoma have COX-2 expression?

Answer 23

75-88% express COX-2 (vs 0% normal prostate tissue)

Question 24

Predilection for bone in prostatic carcinoma may be mediated by what 3 things?

Answer 24

TGF-B, PTH-rP, endothelin

Question 25

Mets from prostatic carcinoma to bone have what action on bone? Osteoproductive or osteolytic?

Answer 25

More commonly osteoproductive, but can also be osteolytic Skeletal metastasis most commonly OSTEOBLASTIC in nature

Question 26

MST of dogs with prostatic carcinoma treated with NSAIDs vs no treatment?

Answer 26

NSAID MST 7m (6.9m); another 2018 study said 1.7m | <1m (0.7m or 21d)

Question 27

What % of dogs with prostatic carcinoma have a BRAF mutation?

Answer 27

85%

Question 28

What is the benefit of systemic chemo for prostatic carcinomas?

Answer 28

Unclear

Question 29

What tumors usually affect the soft tissues of the penis, prepuce, and scrotum in dogs? What are the most common neoplasm of the canine penis?

Answer 29

TVT, SCC (most common ones), sebaceous gland adenoma, mesothelioma, papilloma, lymphoma, plasma cell tumor, mast cell tumor, hemangioma, melanoma, fibrosarcomaTVT and SCC

Question 30

What bone tumors can arise from the os penis?

Answer 30

Ossifying fibroma, benign mesenchymoma, multilobular osteochondrosarcoma, osteosarcoma OSA behaves similar to axial OSA

Question 31

What is the tx of choice for penile tumors?

Answer 31

Perineal urethrostomy and penile amputation

Question 32

Tx for TVT?

Answer 32

Chemotherapy with vinc, not sx, also responsive to RT

Question 33

Mineralization in the canine prostate can be due to what?

Answer 33

In intact dogs - prostatitis, BPH, cysts | In neutered dogs - 100% PPV for neoplasia

Question 34

What should the size of the prostate be in a neutered dog?

Answer 34

Small; a normal sized prostate in a neutered dog is abnormal

Question 35

What % of dogs with prostatic carcinoma have a concurrent UTI?

Answer 35

33-36%

Question 36

Prostatectomy should be considered in which dogs?

Answer 36

Dogs with early stage dz and no capsular involvement

Question 37

What % of dogs undergoing total prostatectomy develop major complications, transient incontinence, and permanent incontinence?

Answer 37

Major complications - 16%: dehiscence, uroabdomen, prepubic herniation 60% transient - resolved within 4 weeks 35% permanent incontinence

Question 38

In the VSSO study where dogs were treated with prostatectomy, did the addition of chemotherapy prolong ST?

Answer 38

No

Question 39

What is the DFI and MST in dogs with prostatic carcinoma when treated with prostatectomy, NSAIDs, and chemo? Negative PI in the VSSO study?

Answer 39

DFI 2.7m MST 7.7m 1-yr SR 32% and 2-yr SR 12% Histologic extracapsular extension MST 4.6m

Question 40

Overall clinical response rate and MST of dogs with TCC and prostate involvement when treated with chemo and an NSAID?

Answer 40

Clinical response 33% | MST 3.5m

Question 41

Negative PI in dogs with prostatic carcinoma when treated with chemo + NSAID?

Answer 41

Intact male status - shorter MST Presence of CS - shorter MST Metastasis to sites other than lungs - shorter MST Tx with NSAIDs alone

Question 42

Survival time of dogs with prostatic lymphoma? How does it usually present? LN involvement and multicentric dz? Most common phenotype?

Answer 42

Mean ST 2m; 2 dogs tx with chemo survived for 1 and 10m 56% had LN involvement and all appeared to have multicentric intra-abdominal dz High grade T cell lymphoma Absence of mineralization on AUS

Question 43

Prostatic tumors in cats? Most common one? Survival time?

Answer 43

Rare Adenocarcinoma Most die within 3m