umors of the Urinary

AL FEATURE
umors of the Urinary
System in Dogs and Cats
Part ll. Upper UrinaryTroct
The optionsfor managingtumorsof thelowerurinary traft wererepart II disuiewedlast monthin Part I of thistwo-part presentation.
c?,.sses
the clinicalsigns,diagnosis
, and treatmentof tumorsaffecting
the upper urinary tract. Renallymphosarcoma
(LSA) is the most
commontumor of the urinaryslsfemin cats.tRenalLSA is rare in
dogs;howeuer,
epithelial
tumors,nrchosrernl cellcarcinoma(Rcc),
accountfor >75 percentof caninerenal tumors.2't
Nephroblasnma
is a congenitaltumor with both epithelialand mesenchymal
components.2The majority of renal tumorsare primary and malignant,
ahhoughmetastatic(Figure r) and benign tumorshaue beenreported.2'')
ClinicalSigns
Exceptfirr the skin lesionsassrrciated
with renal cystir.len,rirrcinomas
irr
54
Veterinary
Forum
PeerReviewed
Gennan Shephercls,l,'the clinical
findings in ctrgswith renal trun()rs?rre
nonspecific, such as abckrminal enlargernent,and trrirrarysignsirre trrrcommon.l'5 Mucous metnbrirnescan
be pale in cars with renal LSA| or
congesteclin c.logs
and cats with paraneoplastic polycythemia.lI Seconclary
polycytherniirmay be ln()re common
with renal turn()rsbecirtrse,
in humans,
the urajority .rf rcnal carcinomasinvolve the proximal convoluted tubule,
which is the main site c'rferythropoietin procluctirxr.ll Litmenessmay be
causctlby either skeletallnetastases
or
I
l
hyps1111yph1.
ostet'rp;r1l1y.I
August2000
I cuNrcALFEATuRE
Diagnosis
Urlnolysls ond Urlne
Sedlment Cytology
Btopsy
Biopsy is required for definitive
diagnosis of urinary tract tumors and
can be obtained by fine-needle aspiration, needle biopsy,or surgery.2'2o
Fineneedle aspiration and needle biopsy of
renal lesions can be performed using a
Proteinuria is a common finding
in patients with renal tumors.zHematuria can also be found in dogs and
cats with renal tumors, such as hemangiosarcoma, hemangioma, or renal pelvic transitional cell carcinoma
(TCC), although hematuria is un-
Flgure l-Metastasis of a malignant
common in patients with RCC.2'5-7'14
melanoma into the kidneys. (CourThese findings are not specific for tutesy of Malcolm P. France, Ph.D.,
mors of the urinary system,and urine
M.A.C.V.Sc.)
sediment cytology is rarely diagnostic
for renal tumors.4'14
Blood Tests
Hematology and serum biochemistry findings are usually normal or nonspecific.2-5 A mild to
moderate normochromic, normocytic anemia can be caused by either
hematuria or bone-marrow suppression secondary to chronic disease.
Atypical or neoplastic lymphocytes
can be seen in I 5 to 60 percent of
cats with LSA.'5 Uremia may result
from neoplastic obstnrction of urinary outflow, bilateral renal tumors,
or age-relatedrenal failure.l'll
lmoglng Studles
Survey abdominal and thoracic
x-rays, contrast radiography, ulffasonography, and computed tomography
(CT) are imaging modalities used to
identifu the presence and extent of
tumors in the urinary system. Sublumbar lymph-node enlargement,
renomegaly,and metastaticdiseasein
the pulmonary parenchyma or skeleton, particularly the lumbar vertebrae
and pelvis, may be detected using
plain radiography.2In one study of
primary renal tumors in dogs, a mass
was identified in 8l percenr of abdominal x-rays and was localized to
August2000
the kidney in 54 percenr of cases.2
Excretory urography has been
used to identifu a renal masssuccessfully in 96 percent of patientszwith
abnormal findings, such as a spaceoccupying renal mass,variable opacification of the renal parenchyma, and
distortion of the renal pelvis.6
In humans, the use of ultra.
sonographyhas enabled earlier diagnosis and more successfultreatment
of renal neoplasia.l6Renal tumors,
except for LSA, produce a mixed
echogenicity, with disruption of the
normal renal architecture.lT Renal
LSA is usually hypoechoic.rTUltrasonographyis also useful in detecting
neoplastic involvement of regional
lymph nodesand adjacent structures,
such as the adrenal gland.ri
In humans and small animals.
CT scans are used for the diagnosis
and local staging of renal neoplasia,
with a high correlation between CT
findings and gross pathology.rE're
Magnetic resonanceimaging is an altemative to CT and is preferred for
identifiiing adjacent vascularand visceral invasion, especiallyif surgeryto
sparethe kidneys is planned.rsOther
imaging techniques include caval
venography and scintigraphy.r8
Peer Reviewed
blind, ultrasound-guided, laparoscopic, or open technique.zoSurgical biopsy, staging, and definitive treatment
are preferred for unilateral lesions;
however, percutaneous biopsy should
be performed with bilateral renal lesions or suspectedrenal LSA. Ultrasound-guidedneedle biopsy is a rapid,
safe,and accurate technique for ciiagnosing focal and diffi"rse renal disease.2oBlind percutaneous needle
biopsy can be performed in cats if the
kidneys can be immobilized during abdominal palpation.2(]The most common complications of needle hiopsy
are minor localized hemorrhage, mi.
croscopic hematuria, and tumor seed.
ing.to
RenalTumors
Lymphosarcoma is the most
common tumor of the feline urinary
tract.r In dogs,RCC is the most common tumor of the kidneys.z-aOther
tumors of the renal parenchyma
include fibrosarcoma, hemangiosarcoma, chondrosarcoma,and nephroblastoma.2-5'llMesenchymal tumors
are rare, accounting for only six of 54
primary renal tumors in dogsz and
one of 19 renal tumors in cats5:however, these tumors are aggressiveand
highly metastatic. The prognosisfor
nonlymphatic mesenchymal tumors
is grave, with a median survival time
of eight months following surgical
excision.2Benign renal tumors have
been reported but, except for hemangioma, are usually asymptomatic and
are incidental findings in necropsy
Veterinary
Forum 55
I cuNrcALFEATuRE
Flgure 2-Renal adenocarcinoma
affectingthe left kid'1O-year-old
ney of a
mixed-breeddog. (Courtesyof Malcolm P.France,Ph.D.,M.A.C.V.Sc.)
studies.2'l'5'?Renal pelvic tumors,
which are rare, include TCC and squamous cell carcinoma (SCC1.z'tr
Renol Cell Corclnomo
Renal cell carcinomasare predominantly seen in older, male,
medium- to large-breeddogs.These
tumorsare largeand usuallyunilateral, with left and right kidneysbeing
(Figwe 2). They
equally affected2'a
are classifiedas solid, tubular, and
papillary on the basis of histologic
pattems; however, most exhibit a
mixed pattem.3 Metastatic disease
wasdetectedin the lungs of 54 percent of dogswith RCC, the abdominal cavity of 54 percent, and the
regionallymph nodesof 27 percentz;
metastaticdiseaseoccurredin six of
l0 cats with RCC.5 The most common metastatic sites are the lungs,
liver, ipsilateral adrenal gland, and
regionallymph nodes.2'l'5
lnvasion of
RCCs into the caudalvena cavaand
tributary veins with the development of a tumor thrombus(Figrre 3)
can complicatesurgicaltreatment.
The median survival time
for dogswith RCC is eight months,
56
Veterinary
Forum
Flgure 3-Renalcellcarcinoma
invadingthroughthe renal veinand into the caudalvenacava.(Courtesyof Malcolm P.France,Ph.D.,M.A.C.V.Sc.)
but surgical resection has resulted in
prolonged survival of up to four
years.2Stage and grade are the most
important prognostic factors, with
poor median survival times reported
for patients with regional or distant
metastasis.tE
The poor survival times
reflect the advanced stage of disease
at diagnosis, difficulty in completely
excising the tumor, and high metastatic rate.z
Cystodenocorclnomo
Renal cystadenocarcinoma is an
autosomal dominant condition in
German Shepherds but has also been
reported in a German Shepherd
cross and a Golden Retriever.ro Renal cystadenocarcinomas are always
bilateral, and deterioration of renal
function is slowly progressive.roThey
are associated with nodular dermatofibrosis and uterine leiomyoma.lo Nodular dermatofibrosis is
present in all cases and appears as
small, firm, mobile subcutaneous
masses.Clinical signs and the size of
skin and uterine tumors increase
with advancing age. In one study,
metastaseswere detected in 47 per-
PeerReviewed
cent of cases, with sites including
stemal and aMominal lymph nodes,
liver, lungs, pleura, and peritoneum,
and were more common with large,
solid, poorly differentiated tumors.t0
The main causes of death are renal
failure, metastatic disease, and secondary skin infections.lo
Lymphosarcomo
Lymphosarcomais the most
commonrenal tumor in catsr(Figne
4). Renalinvolvement is observedin
up to 45 percentof catswith LSA.'Ja
Middle-aged,male cats are usually
affected,and retroviruses,such asfeline leukemia virus in the United
Statesand feline immunodeficiency
virus in Australia, are frequently asRenal
sociatedwith LSA in cats.r'2a
LSA is diagnosedby percutaneous
fine-needleaspirationor renal biopsy and stagedaccordingto palpation,
radiography,hematology,biochemistry bone-marrowexamination,and
the extent of tumor involvement.
Lymphosarcomaaffects both kidneys,despitebeing clinically apparent in only one kidney.r'24
There is a
high incidence of central nervous
August2000
CLINICALFEATURE
system involvement in cats with renal LSA.I Chemotherapy is the recommended treatmenr of cats with renal
LSA (TablesI and 2).
The stage,degree of response,feline leukemia virus
(FeLV) status, and renal function are prognostic factors
for cats with renal LSA. Partial respondershave a mean
survival time of 75 days,compared with 408 days in cats
having complete response.lThe mean survival times in
cats testing positive or negative to FeLV is 267 and 610
days,respectively.rCats with mild abnormalities in renal
function survived longer than did those with moderate
to severeabnonnalities.I
Flgure 4-Lymphosarcoma primarily affecting the cortical area of the kidney of a cat. (Courtesy of Malcolm p.
France,Ph.D.,M.A.C.V.Sc.)
Nephrohlostoma
Nephroblastoma is an uncommon congenital tumor
originating frorn the metanephric blastemaand resulting
frorn abnormal differentiation of the kidney during ernbryogenesislrand is usually diagnosedin animals younger
Week I
Mncristine,
l-asparaginase,
prednisolone
r Week 2
Cyclophosphamide,
prednisolone
than l2 months of age.rIt is a mixed turnor consisting of
I Week 3
blasternal,epithelial, and mesenchymal componenrs ll1
Doxorubicin,
prednisolone
varying stagesof differentiation.rr Nephroblastoma deI
Week 4
stroys the renal parenchyma by invasion and compresPrednisolone
sionr] (Figr,rre5). Local invasion of adiacenr srrucrrrres
I Week 5
occurs if the tumor penetrates the
Mncristine,prednisolone
renal capsule.rlNephroblastomais
I Week 6
Cyclophosphamide,
prednisolone
graded as either favorable or unfaI
Week 7
vorable on the basis of histologic
Doxorubicin,prednisolone
findings.z5A sraging system based
T Week 8
on the extent c-lftumrtr invcllvement
No chemotherapy
and surgical findings has been cleI
Week 9
Week17
veloped for use in hurnans with
Mncristine,l-asparaginase
Mncristine
nephroblastona2t (Table3).
I
Week 1O
t Week 18
Nephroblastoma is highly maCyclophosphamide
No chemotherapy
t Week 11
lignant. The lungs and liver are rhe
I Week 19
Vincristine
Cyclophosphamide
most common sites for metastases,
I
Week 12
I
Week 20
but other sites include the regional
Methotrexate
No chemotherapy
and distant lyrnph ntx-les,adrenal
r Week 13
I Week 2l
glancls,thyroid gland, pleurA, conMncristine
Vincristine
tralateral kiclney, and appendicular
I
Week 14
t Week 22
skeleton.rrIn hurnans with nephCyclophosphamide
No chemotherapy
roblastoma,rhe renal vein is inT Week 15
I Week 23
Doxorubicin
volved in 10 percent of casesand
Methorexate
the caudal vena cava and rieht atri-
August2000
PeerReviewed
Veterinary
Forum 57
CLINICALFEATURE
flgure S-Nephroblastoma primarilyinvolvingone pole
of the right kidney in a four-month-old dog. There is
compressionand invasionof the adjacentrenalparenchyma. (Reprintedwith permissionfrom WatsonADJ, Rothwell TLW, Moore lD, et al. Nephroblastomain two dogs.
Aust Vetl. 1 987;64:94-96)
um in a firrther five percent;however,
there are n() rep()rts of nephroblastor.nainvading the vascularstructures
in animals.l]'rt
Effective diagnrlsis,staging, and
multimodality therapy have drarnatically reduced the morbidity and
mortirlity in chiltlren with nephroblastoma.ln hunrans,p(x)rpr()gn()stic
factors include the presencetlf bone
rnetastases
and tumor spillageduring
surgery.l5Nephroureterectorny, with
tlr without adjunctivechernotherapy,
has resulte.lin survivaltirnesof eight,
18, and 2 I months in three dogswith
l' Becauseof siminepl-rroblastrlnla.l
larities between nephrrlblastomasin
hurnans and those in dogs, the combined approach of surgery, chemotherapy, and radiatit)n therapy to
treat hulnans may provide effective
than the rate of RCC in clogs but
higher than the rate ir-rctrts.l']'5An
associatitlnbetween renal pelvic tumors and struvite calcrrli has been
postulated and is trpparently ctrused
I
I
I
trcatment of canine nephroblastorna.
Renol Pelvic Tumors
Renal pelvic TCCs are pedunculated, rnultikrbulated, and locally aggressive (Figure 6). The metastatic
rate of renal pelvic TCC is lower
58
VeterinaryForum
Flgure LTransitional cell carcinomaarisingfrom the renal pelvis of a dog. (Reprintedwith permissionfrom
Goldsmid SE,BellengerCR, WatsonADl, Allan CS: Renal
transitionalcell carcinomain a dog. I Am Anim Hosp Assoc.
1992;28:241-244)
I
t
by squamousmetaplasia and malignant trirnsfi)rur:rtionof the urothelium due to irritation by renal calculi.rr
In humans, the prognosisclepen.ls.xr
nrultifilcality, tr,n.lx)rgratle anel stage,
StageI
Tumorlimitedto the kidneyand the renalcapsuleintact
Tumorcompletelyexcised
Stagell
Tumorextendedinto adjacentstructures
Tumorthrombior vascular
extension
of tumor evident
Localspillageof tumor contentsduringexcision,
but tumor completelyexcisedwith no evidenceof residualtumor
Stagelll
Tumorextendedinto hilaror periaorticlymph nodes
Diffusespillageof tumor into the peritonealcavityduringexcision
Evidence
of tumor in the peritonealcavity
Localinfiltrationof vital structuresprecludingcompleteresection
Stage lV
Evidenceof hematogenousspreadof the tumor
StageV
Bilateralrenal involvement
Peer Reviewed
August2000
Heartearde
iffi/Wnni-Pn'
CAUnoil: fde'a l! S A r bw 'eilnds Ihs druqlo usebvfl 0n$e
orer ol a Lcenw verehndrdn
lilorcAnoilS: for u* rnd@slo qewnl canrneheaNom d seas€
nssue$&; ol riam0 1 alar'ororrdrd
0r ela lntfu
mmi. tof a-mnth {30da6r al€r nlft r.0' a'O l0 lhPredlaen
dnd[onrol of a$ards lfor&"/a an6, forJscat6leontna)anl
hmtrums rlrarloslonr ar.rnffi LhcnatE slenxephaln
Atrlcstafia Dtathensel
00S GE N$flIGARD! P[s lrvemsm/ffantel)Ctuables should
iladmnslsedorallvatrcnlhlyrnQoahal6ersmendei
a . 1 un6* lml ol6 ftgol,c,ffinne'
tiloE@12 72ftg/lbl
o { 5 a o r o r s n r e l i aF
s r u l e s l l ) F I q 1 2 2 7n 0 4 b ) 0 1 m
ueqhr lk'e(!m#Csing{hedule{o
Fmnl!noi@1t
n p d n r o r m d r g e a 5 e a r dl hl oe t r e a l m n l a d c o n x o l 0 l M r o (
Cimbld
PilIod
. l
n !l
5l lW
I
I
l|m.din
Codd
Sr.q
l$ftq
?72mq
hnil.l
Cod.il
ll4ro
?77hq
hilhliq
lndbnon
8..
Gr*n
Brffn
Bus s fsommedd lor dqs 6w*ls ol aqeandold€l
StAflTGAnD
t o r d q s m r l m i b # f i e a m r r y a i e c m b x a l 0 n0 l l h € s e ( @ a b ! € s
nemd€ onlyom chewabeal a lme toil $e
AolllillsllAnoil:
Io, Mld bhserc'd R€turnliEcfdwrhfie rerornrngcMabes
ro il! trr ro protd lhe prdd lrcm lqhl Beca6emon dqs Ind
H I A F I 6 A F D P l u s N l a r a lbheeg d w l c a n h o l l e r e d l o f t e d q b r
fand Afiefilanlelr.I roy h addedinlrcl Ioa snralamounlol dq
i00d Ih€ chewabksholldM admrnnerd m a mannerlhal
em0ulafts t[ dq l0 [hee ralherlhanlo 5*a 0w !!ilfoul ciet!ng
Chcvrbie!mayb brciei nh ptres andldl0 dq\ lhal normallt
Caf€should& lalen $ar rhed@ [onsumeslhe Lampetedo€
andirealedanrmahshoudk 0bleNd lof d lew mn0te5aller
admnffanonto ensurethal panol the6se I ml losl d re|dl6
ll r 6 5u5fled tiut anyollfu dosehasker losl rdo$nq s
dumg h
N[AnTGA80PlusshouldbeEvenal mcnthy Inleryals
ftrd o{lheveartrn mo{ul€s lvtrlotrl @!€nralvcarryrng
n1ftt!e heatuormlafrde areaLl!3 TheInilradlse mun be gten
?r thrna monfi 130dayslaller$e d43 ltrl €rgrsurel0 moquiles
T h €l i d l d N m o n b e g r e n w i l h f a n o n l h1 3 0 & F l a h e rl h e d o { s
as er@5urel0 molu lm\
When'eDar m dnlrh€rl€a(sorm prevenlwproducln a heanworm
d,sdas€
orevsl,onM@ram.$e trl &se ol HIAFICAnDP s m0il
M q'rsq{ilh n a monlh130drs) 01lhe la$ doseol lhe lofrul
i lh€ nletoal&Ren dos€serceds a moilhl30da$l, theelircilv
.t,€'medil cdnb rdtred Tltrel0re loropha Edorma(e
lhErheraLe mun h qven otre a m0nlh0nd amul lhe gme dat
rl lhe mofrh I teatrunl s deayei.wh€lherbl a le$ fiys 0r manv.
Pld andesumplond the
mmedile uearmnlwili HIANTCAnD
r, m nm le lhe opFilunilt l0r l&
recommdd dcsnqregrmen
de!€ ocmenlol aduI hearMorntr
gus alsogovr&s efiel ve
l,lonhlv fiearmnrw{h HIARTGAnD
lr€ah€nr andccnloloi asads /I .rnr f /eonreldd Mlmms
iA cennun U stcbe?kala A b/dirpnserCleils $oJd & adsd
rl mrasufestoh laten to preenl rernl&lonwlh nleilna taasEs
Pus Ch*abes q veno,allvulnq fie
EfFClGt HTARTGARD
recommendddoseandrelrmenare€llsl v€ dganil lher$ue dilal
! r d o € , rr , " d i . l , r ' o r d m o n F , 3 0d a ' s ld i e r ' 1 f t n o n a f u .a sa
', .
aduilstageHEAnI6AF0Pl-.
o ewnt th@tofento,lhe
Cq.,db psJe als ellelm aqa,rotcn re du os lf ani I /@r J
(A drDut. l] slemeqhela. a btilhensd
rd futffims
ad ireldtEls. HEARTGAnDP[s
ACCIPI llllTl InacceDlabrlrl
ahe,lab es we lhosf, td be an aceFable oral dosao€lom 1i.l
rd\ (oNurEdar fr6loflsrrDWfte roldryol dogs
Pf,ECAUnoNS: All dos sMld be lested lo er.st! kal]W
''nr on elore stan'miteamdwilh H[AqTGAR0
Plusd(h s nol
e-e r ,e agann adlxD df,t's Inldsdoglmuil be lealed to
'." D.- ddJltheaMms afo n(lollar# mrorerrilElrq a g0g d1
i rh NIAFIGMDPlus
In n HABTGAFO
msofrl&r4 @ be hlled h h rffi
\\firh w
PlusInolettelve
P[sar lhe remanded &s lml. NI,ARIGAR0
ld m['otrlanaedeaa& A mrld]rype@nlrllly tyF readff.
panrculaf
mfiollare
d
dyn!
ad
! rm[rn!
tesurobly dw b &ad
a tannmtdilfua bs beencbsswdInchnrslfEBwrU @ffitn
aloe aller treahent ol sw do{s fial haw cilculalig moollara€
X..f dil! .id rll &|l. d ol $. n.ch ol childm
. rr\e o' resl.on bv \Fans. L erls shoild k dd, (S !0 (o^ld,l d
phA[]an rmiEdately PhFoansmat (ontad a Pc sonContolCenl€r
hr ddncecomemrrucases0l Ingeil0nbi humans
Sr.'e ar conto d roomremftrarore0l 59 86 f 115 3l i frdsl
lndm(al l€ld t a ! wlh N$nTGAR0P[s
loWnSEnilCnolisr
. 9 t r i l , mo d a " t a i n h r ? l ' o L r o ' d c sA 6 a u a e l , o b s e l d
I l= ol MmrnrsErs oo*sr Ik lo Mrro&.erse read o.s rdrF
oeg€sran/le$arw
beeni€Fnd to wrr{lh€ us€ol HEARTGABo
vomI ru andera dratrheamydfra$saGra. ilalrprq cmusons
HushasFen sMm loh brqur{alenl l0
Slf,ElY: HEABTGT.Fo
NtAntGAffow$resffir rc ttu b@vahbil! ol vermftln Ttu fts
qus
,{rys
at r&R_6lcDaf le ea$ S e?a'd
d i[ID_GAFo
r ' L e r m f rt r t b n " o ' o r 5 d e 54 l r r . e r n e c ! ' n d ' c d ller a t l e n a '
dms ol lhe Co[e bieeilaremoresnllw lo tEefiet 0l @meln
admn n€redat elealdbse lmklmore than16h€s fte bqel
use ere ) han dq\ ol olhefbreedsAl e evatd dosesgnslve dogs
shfid ad!€rtereelffi S[h rtludedmldrra$s.*Fes]m alara
temo6 drmhm Nrestr 'trumbemy erclabililysluprcomaad
- 0 y q . ( o rt o , ( i l , d l ' 0 . n e s . h e
rear rg!-G[o0 dem.nrl6
rftomruffi &te 60ao.o r t"sI\e('o' e) nesLI\ojlhe5e
tBk andb mu !aeD sludGssu0F( tE sl€ry01 fIARIGAR0
pfdods n dogs ,tludn! ColLes.witn usd as rtromftnded
SAnICAI0PIushas shM a wde rorqil 0l salel illE
rtr0mnded dos e!€l ndogs rft 0d nqpreqnail0f breedrr!
Ol'nes (lro dc!( dt pumresa!tr 6 (' ro'e ^Pel\ k ([aGl fi a[
- a r . c m m . l , j e i ' L e d c o l l as .d O ( 5 h d - @ , d r l h en l n c s .
annb[t cs vecLn€sandilefodqeF'al onshavebeendmmflsed
prevenlongq]ram
P]osIna heaturm d,sease
!rrh H[AfrTGA8O
rus lhereNasa margrMl
n onetral Mere smMshadFnN
rduilon melJcaq agarnstLnleirnarumald€s P$rblydue to a
thanq€n Inlen naltanll !m
HolVSIrPPUE0:FtaF-GAFDol"s s a.a hble r rr'* dosr4P
r . e r t h ( , , e 0 0 5 A 6 [) { n o n t ' o rd @ 5o l o f r e , e 1+ e q a s [ a c h
r'"'irncmer ncomm'entcaronsri'69and'2cwaores
hw Pa@n! otlqamn ol Menal
huatail
lndd 9l lv l0lEl sHdrd rf,ontralnus Cuaran€ir€msand
ccdmns aNand a olhercos$erore$lvercluded
'0
frrR 5td6 LMd
h *F{al
a qelffie,n
tus turc
r,€ !-oalos ocis o'ele s iilq'6AF0 PIL\Chenads 6e
NItFCtPIOfiSim lbmwfl u,me) ftAVoF TASS! tula on i e
12
19S
ffie
tun
5fi
hEtdG
ol
a
0l
h ACNeils
?8e$hs
W
jDt. on lle lvfillel Dvnam{s r
b " i A ! ' G t q o . a , s r r e r d I d e r d r d { . l - e 0 q & F d n dl o g o
iABSre
A a rademdl d vs;
! \tEFctol0q dnd'LAV0F
r@slef€dtaderuds ol Nilan[ OztmM€nallmiled keln. NJ
N G Do . r m z r 7 7 T V J
I
I
CLINICALFEATURE
DNA ploidy, and history of bladder
TCC.26
UreteralTumors
Primary ureteral tumors are rare
in animals and usually occur sec'
ondary to neoplastic diseaseof the
kidney, bladder, or retroperitoneal
space. Reported ureteral tumors include malignant TCC and leiomyo'
sarcoma and benign fibropapilloma,
papilloma, leiomyoma, and fibroepiSegmental ureterthelial polyps.2r-2r
ectomy can be attempted for benign
lesions. but tension-free end-to-end
ureteral anastomosis is difficult to
achieve. Nephroureterectomy is the
preferred treatment of malignant
ureteral tumors, although nephronsparing surgerycan be usedfor distal
preoperative percutaneous anglolnfarction with ethanol, inflatable balloons, microspheres,or gelatin sponges
may reduce hemorrhage and pain
and result in easier removal of the
kidney and ureter.16
The contralateral kidney is examined for evidence of neoplastic
disease before surgical resection of
the affected kidney.2 Radical en bloc
resection of all involved contiguous
structures should only be considered
if the entire diseased area can be
completely removed. The hilar vesselsshould be isolated and ligated before kidney mobilization because
large tumors often have arteriove-
Nephroureterectomy
is the preferred
ureteral tumors.
of
treatment
Surgery
Surgical treatment depends on
the behavior of the tumor, presence
of metastasesand bilateral renal
involvement, and invasion of the
caudal vena cava and adjacent structures. Nephroureterectomy is recom'
mended for the grading and staging
of nephroblastoma and definitive
treatment of all malignant renal and
ureteral tumors, except LSA.I'25
Nephron-sparing techniques should
be used for benign tumors and bilateral diseaseto reduce the risk for renal failure.25
malignant ureteral
tumors.
nous fistulae.rsThe renal artery is ligated first, followed by the renal vein,
to prevent tumor embolization. Ligation of the renal vein should be delayed if a tumor thrombus is present.
The tumor thrombus is removed en
bloc with the kidney.25In humans,
cardiopulmonary bypassand deep hy.
pothermic circulatory arrest are often
used to resect masses invading the
caudal vena cava. However, because
Nephroureterectomy
To performnephroureterectomy,these techniques are not readily
available in veterinary practice' oc'
the kidney is approached through either a standard midline ventral celiotomy or paralumbar laparotomy,
but the former is preferred because
thorough examination of the abdominal cavity can be performed more
clusion ofthe caudal vena cava ts ac'
ceptable only if the tumor thrombus
does not extend above the level of
the hepatic veins.ls
Perinephric fat should be re'
easily.With highly vascular tumors'
moved with the kidnev to reduce the
60
Forum
Veterinary
PeerReviewed
August2000
FEATURE
I CLINICAL
risk for tumor spillage and incomplete excision becausemicroscopic
infiltration through the renal capsule
is relatively common.z'r6
The ipsilateral ureter should be excised with a
cuff of the urinary bladder because
TONO.PENXL
The world'sfirst completelyportableunir
for measuringintraocularpressure(lOP)
the tumor can extend along the
ureter.2'15
Concurrent adrenalectomy
is controversial because the inci-
o Documented accuracv
o Easy to use
dence of ipsilateral adrenal-glandinvolvement in humans is lessthan l5
percent; however, it is recommended
for large tumors or tumors in the cranial pole of the kidney.16Samplesof
o Results in seconds
o Digital electronics
o Provenreliabiliry
o Profitable
the regional lymph nodes should be
taken for aspiration or biopsy because visual evaluation of nodal involvement is unreliable.2'16'25
The
kidney and ureter should be submitted for histopathologic examination
following removal.
Portlol Nephrectomy
Nephron-sparing
surgeryis recommended for local excision of benign tumors and preservation of renal
function in patientswith bilateral malignant tumors, a solitary kidney,
or compromised renal function.lE
Nephron-sparing surgery can be performed for bilateral malignant tumors
if the tumor is confined to the pole of
one kidney and has not invaded the
vascularor collection systems.25
How.
ever, animals with malignant renal tumors are usually not good candidates
because multicentriciry and invasion
of the renal capsuleare common.l8
The two main nephron-sparing
proceduresare tumor enucleation and
partial nephrectomy.?'27Partial median nephrectomy has been described
for the management of renal hemangioma in a dog.?Surgical marginsof 1
cm of normal renal parenchyma are
recommended.2TTemporary renal artery occlusion decreaseshemorrhage
Veterinary
Forum 6tl
"A
pen-sized,handheld, battery-operaredapplanation
tonometer (Tono.Pen XL) has been found to be reliable for
measuringIOP in the dog and cat. . . . Its price, easeof useand
correspondenceto true IOP will make it attractive to many
veterinarians.
. . . Every veterinaryhospiral or clinic should
have a tonometer."
-Vet
Clin. Nomh Am Small Anim Pract, D.E.
Bioolcs,
D.V.M ,Ph.D.,VoL
.
20,No.3 M ay 1990
DAN SCOTT & ASSOCIATES
235 Luke Court, lVestervilleOH 43081
Toll.Free: 888.TONOPEN
614.890.0370 o Fax 614-818-9330
ACircle No. 105 on VF Response
Card.
I
CLINICALFEATURE
but can cause acute tubular necrosis or ischemic
nephropathy if ischeuriatirne exceedsJ0 n'rinutes.liLocal
hyptlthermia using either ice slushestlr advancedcooling
coils can prolong the duration of sat-erenal artery
occlusion.rTMannitol should be administeredfor l0 rninutes beftrre occlusion of the renal artery,
and the kidney should be cooled ftrr 15
rninutesbeforepartial nephrectomyis per-
At the University of Sydney,the irrductronl.rrotrlcol
for cats with LSA involves the adminisrration of vincristine 0.025-0.03nrg/kginrravcnously(lV), L-asparaginase
450 lU/kg intranruscularly(lM), cyclophosphamidel0
mg/kg orally, doxorubicin 1.0-l.l nrg/kg lV, rnerhorrex-
In cats and dogs,
formed. Maintaining patency of the renal
vein decreasesintracellular edenraand increasesrenal plasnra flow.li Other techniques used to perfonn nephron-sparing
surgery include ultrastlnic asl.rirationand
lasers.li
chemotherapy is
the recommended
treatment of
ate 0.8 rug/kg orally, and a redr.rcingdose
of prednisolone fronr 4 mg/kg orally in
week I ttr cessatiorltlf prednisolone therapy in week 8. The wcckly order of adt'ninistration of these chcurotherapreutic
ager)tsis given in Tuble I .
The rnainterraltccpl()t()ctrI involves
rhe adnrinistrationtlf vurcrisrrne0.025-
lymphosarcoma.
Adjunctive Treatment
Chemotheropy ond Immunotheropy
for Renol Cell Corcinomo
hr humans,RCC is consideredchemoresistant
be-
0.03 nrg/kg lV, cycl.r-phosphamidel0
rug/kgorally, and nrethorrexate0.E rng/kg
'l-he
orally in the scquencegivcn in Table2.
ruaintenan.c
cycle is repeatedevcry two weeksfbr thc filst six n.ronrhs.
Thc prot.rcol is adurinistercdevely rhrce weeksand therr
cilr-lseresp()llserates are generally lcss than l0 percent.ls
Chernoresistanceis most likely causeclby the presenceof
the rnultidrug-resistiurtp170 glycr,g'rr()rcir-l
oll the surface
of tumor cells.l*The use of multiple chemotherapeutic
agentsdtles not intprrlve rcsp()nseratesbut increasestoxicity. Currer-rtinvestigzrtionsin humiurs include con'rbining
vinhlastine with immuntltherapytlr multidrug-reslsranr
antag()llists,such ascycltlsporinanalogs,tan'roxifen,tlr verapamil.rs
In humans, RCCs are resistantto chen'rotheratrry,
hor.
rnonal therapy, and radiation therapy but immuntltherapeutic agents, such as recornbinant interleukin-2 and
interferon-ct, have providecl encouraging results.ls hnmuntltherapy was initially investigatedbecausenephrectomy resultedin regressionof metastaticlcsitlnsin hurnans
witl-r RCC becauseof an enhanced imurune r€sl-ronse.ls
This effect has not been observed in anir.nals,and imrnunotherapy and chemotherapy have not been investigated in the treatrnent of RCC iu cats tlr dtlgs.
Chemotheropy for Lymphosorcomo
Cheu-rotherapy is the recommended treatrnent of
LSA in cats and dogs.The induction and mainrenance
protocols used at the University of Sydney are sulnrnarized here. Other prorocolshave als.rbeen described.r,la
In one study,r6l percent of patienrs wirh LSAs had a
ctlrnplete rcsp()llse,with n'reanrenrissionand survival
tirnesof 172 and 408 days,reslrecrively.
August2000
Veterinary
Forum 63
ACircle No. 107 on VF Response
Card.
FEATURE
CLINICAL
every four weeks if the cat remains in
remission after 12 and 18 monttrs, respectively. Chemotherapy is stopped
after two years if the cat is still in
complete remission.
tion of the affected kidney and ureter
remains the principal method of diagnosis, staging, and treatment.
However, nephron-sparing techniques can be usedfor benign tumors'
malignant tumors affecting both kidneys, or in animals with renal failure.
Chemotheropl and Rodlotlon
Chemotherapy and radiation are recTheropy for Nephroblostoma
In children with nephroblas- ommended for nephroblastoma, but
tomas, surgical resection and chemo.
therapy are recommended for all
stages.Vincristine 0.5-0.7 mg/m' IV
and actinomycin D 1.5 mg/m' IV are
adjunctive therapy for RCC and renal pelvis TCC has not been investigated and, based on human studies,
Y/
may not be effective.
recommended for all stages,and doxorubicin 30 mg/m' IV is added for
stage II nephroblastoma with unfavorable histology and stage III with
ReceiuedFebruary 14, 2000
AcceptedApril5, 2000
favorable histology.z5Radiation therapy is recommended for stagesIII and
IV with favorable histology and stages
II to IV with unfavorable histology.25
In humans, the main concems are the
effects of chemotherapy and radiotherapy on developing organs because
children are more sensitive to the cardiotoxic effecrc of doxorubicin and
because radiation therapy can affect
development of the lungs and spine.25
Actinomycin D has been administered to dogs with nephroblastomas
and has resulted in partial responses
and prolonged survival.z'r3Neoadju.
vant chemotherapy is recommended
for large inoperable tumors, bilateral
disease, and neoplastic involvement
of the caudal vena cava.25
Understandingthe Options
Renal LSA is the most common
tumor of the urinary system in cats
and is responsive to chemotherapy
protocols. The majority of other renal tumors in cats and dogs are associated with a poor prognosis because
the tumors are usually advanced at
the time of diagnosis and presenting
signs are nonspecific. Surgical resec-
64
Forum
veterinary
Acknowledgment
by the LiDr. Liptakis supported
SeniorClinicalFellowonelLonsdale
by The Univenity of
ship sponsored
Sydney.
References
1. Mooney SC, Hayes AA, Matus RE,
MacEwen EG. Renal lymphoma in cats: 28
cats (1977-1984).I Am Vet Med Assoc.
1987;I9l:1473-14?7.
2. Klein, Cockerell GL, Harris CK, et al. Canine primary renal neoplasms:a retrospec.
tive review of 54 cases.J Am Anim Hosp
Assoc.1988:14:443- 457.
3. Baskin GB, DePaoli A. Primary renal neoplasmsofthe dog. Vet Pathol.1977;I4:59L'
605.
4. Stone EA. Urogenital tumors. Vet Clin
North Am Small Anim Pract. 1985;15:597'
608.
5. Henry CJ, TLrnquist SE, Smith A, et al.
Primary tenal tumors in cats: 19 cases
(1992-1998). I Feline Med Strg. 1999;
1:165-170.
6. Widmer \7R, Carlton WW. Persistent
hematuria in a dog with renal hemangioma.
J Am Vet Med Assoc.1990;197:237.?'39.
7. Mott JCB McAnulty JF, Darien DL, Steinberg H. Nephron sparing by partial median
nephrectomy for treatment of renal hemangioma in a dog. J Am Vet Med Assoc.
1996:208:1774-1276.
Picut CA, Valentine BA. Renal fibroma in
four dogs. Vet Pathol.1985;77:42?--423.
Diters RW, Wells M. Renal interstitial cell
tumors in the dog. Vet Pathol 1936;23:74.
76.
10. Moe L, Lium
B. Hereditary multifocal renal
PeerReviewed
cvstadenocarcinomas and nodular dermatofibrosis in 51 German shepherddogs.J
Snull Anim Pract. 1997;38:498 -5Q5.
11. Waters DJ, Prueter JC. Secondary poly.
cvthemia associatedwith renal disease in
the dog: two case reports and a review of
the literature. J '*n Anim Hosp Assoc.
1 9 8 8 ; 2 4 : 1 0 91- 14 .
12. Gold PJ, Fefer A, Thompson JA. Paraneoplastic manifestations ofrenal cell carcinoma. Semin UroI Orcol. 1996;14:216-227.
13. Watson ADJ, Rothwell TLW, Moore JD, et
al. Nephroblastoma in two dogs. AustVet J.
1987;64:94-96.
14. Goldsmid SE, Bellenger CR, \Uatson ADJ,
Allan GS. Renal transitional cell carcinoma in a dog. J Am Anim HosP Assoc.
1997;78:741-2.44.
KH,KurtzHJ,HanCA,Johnson
15. Osborne
lon GF. Renal lymphoma in the dog and
cat. J Am Vet Med Assoc. 1971;158:2058'
2070.
I 6. Lukkarinen O. Surgery for the urinary tract
cancer. Ann Chir Gynrtecol. 1996;85:707'
2.06.
17. Konde LJ, Wrigley RH, Park RD, Lebel J.
Sonographic appearanceof renal neoplasia
in the dog. Vet Radiol. 1985;26:74-81.
18. Bukowski RM, Novik AC. Clinical practice guidelines: renal cell carcinoma. Cleoe
Clin I Med. 1997;64:l -48.
19. Yamazoe K, Ohasi F, Kadosawa T, et al.
Computed tomography on renal massesin
dogs and cats.J Vet Med Sci. 199456:813'
816.
20. Osborne CA, Polzin DJ, Johnston GR. Per'
cutaneous needle biopsy of the kidney. Vet
Clin North Am Small Anim Pract.
1996;26:1461-1504.
21. Hanika C, RebarAH. Ureteral transitional
cell carcinoma in the dog. Vet Pathol.
1980;17:643-646.
27. Berzon JL. Primary leiomyosarcoma of the
ureter in a dog. J Arn Vet Med Assoc.
1979;r75:374-376.
23. BurtonCA, DayMJ,MooreAH, HoltPE.
Ureteric fibroepithelial polyps in two dogs.
I Small anim Pract. 1994;35:593-596.
?-4. Gabor LJ, Malik R, Canfield PJ. Clinical
and anatomical features of lymphosarcoma
in 118 cats. AwtVet J. 1998;'16:725.737.
25. Haase GM, Ritchey ML. Nephroblastoma.
SeminP ediatrSurg. I 997;6:I 1- 16.
26. Seaman EK, Slawin KM, Benson MC.
Tieatment options for upper tract ffarrsi.
tional-cell carcinoma. UroI Clin Norrh Am.
1993;70:349-354.
27. Griffin JH, Flanigan RC. Nephron-sparing
surgeryfor renal cell carcinoma. TechUroL
1996;7:43'47.
Dr. Liptok is o residentin SmallAnimol Surgery
the Departmentof VeterinoryClinicol Sciences,
The Universityof Sydneyin New South Woles,
Austrolio.
August2000