www.bjorl.org
Brazilian
Journal
of
OTORHINOLARYNGOLOGY
REVIEW
ARTICLE
Thyroid
leiomyosarcoma:
presentation
of
two
cases
and
review
of
the
literature
夽
Mehmet ˙Ilhan
¸ahin
S
a,
Alperen
Vural
a,∗, ˙Imdat
Yüce
a,
Sedat
C
¸a˘
glı
a,
Kemal
Deniz
b,
Ercihan
Güney
aaErciyesUniversityKBBKlinigi,DepartmentofOtorhinolaryngology,Kayseri,Turkey bErciyesUniversityKBBKlinigi,DepartmentofPathology,Kayseri,Turkey
Received15October2015;accepted13November2015
Availableonline29March2016
KEYWORDS
Thyroid;
Leiomyosarcoma; Anaplasticthyroid carcinoma; Sarcomas
Abstract
Introduction:Leiomyosarcomaisatumorwhichisrarelyseeninthethyroidgland.Thediagnosis maybedifficultandthetreatmentiscontroversial.
Objective: Theobjectiveofthestudyistoreviewtheliteratureaboutararemalignantdisease ofthethyroidglandwhichhashighmortality.
Methods:Twocasesofthyroidleiomyosarcomaarepresentedandtheprevious23casesinthe currentliteraturearereviewed.
Results:Atotalof25casesofthyroidleiomyosarcomaarereviewed;themostcommon com-plaintwasrapidlygrowinganteriorneckmass,andtenofthe25patientshaddistantmetastasis attheinitialadmission.Fifteenofthe25patientsdiedwiththediseaseinthefirst12months afterthediagnosis.
Conclusion: Thedifferentialdiagnosis ofthyroidleiomyosarcomaisimportantandshouldbe performed withothermalignancies ofthegland, especially withanaplasticcarcinoma. The prognosisispoorandthereisnoconsensusregardingthetreatment.
© 2016 Associac¸˜ao Brasileira de Otorrinolaringologia e Cirurgia C´ervico-Facial. Published by Elsevier Editora Ltda. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/).
PALAVRAS-CHAVE
Tiroide;
Leiomiossarcoma;
Leiomiossarcomadatireoide:apresentac¸ãodedoiscasoserevisãodaliteratura
Resumo
Introduc¸ão: Leiomiossarcomaéumtumorraramenteobservadonaglândulatireoide.O diag-nósticopodeserdifícileotratamentoécontroverso.
夽
Pleasecitethisarticleas:S¸ahinM˙I,VuralA,Yüce ˙I,C¸a˘glıS,DenizK,GüneyE.Thyroidleiomyosarcoma:presentationoftwocasesand reviewoftheliterature.BrazJOtorhinolaryngol.2016;82:715---21.
∗Correspondingauthor.
E-mail:alperenvural@yahoo.com(A.Vural).
http://dx.doi.org/10.1016/j.bjorl.2015.11.020
716 S¸ahinM˙Ietal.
Carcinomaanaplásico datireoide;
Sarcomas
Objetivo:Oobjetivodoestudofoirevisaraliteraturasobreumtumorrarodaglândulatireoide quepossuialtoíndicedemortalidade.
Método: Doiscasosdeleiomiossarcomadatireoidesãoapresentados,eos23casosanteriores relatadosnaliteraturaatualforamrevisados.
Resultados: Umtotalde25casosdeleiomiossarcomadatireoidefoirevisado.Aqueixamais comumfoiorápidocrescimentodeumtumorcervicalanterior;10dos25pacientes apresen-tavammetástasesdistantesnomomentodaadmissão.Quinzedos25pacientesforamaóbito nosprimeiros12mesesapósodiagnóstico.
Conclusão:O diagnóstico diferencial de leiomiossarcoma da tireoide é importante e deve serfeito comoutrasdoenc¸as malignasdaglândula,especialmentecarcinomaanaplásico.O prognósticoéruimenãoháconsensoemrelac¸ãoaotratamento.
© 2016 Associac¸˜ao Brasileira de Otorrinolaringologia e Cirurgia C´ervico-Facial. Publicado por Elsevier Editora Ltda. Este ´e um artigo Open Access sob uma licenc¸a CC BY (http:// creativecommons.org/licenses/by/4.0/).
Introduction
Sarcomas are an extremely rare group of tumors among all thyroid malignancies.1 The sarcoma types observed
in the thyroid are liposarcoma, leiomyosarcoma, and
angiosarcoma.2---4 According to the histological tumor
classification of the World Health Organization (WHO),
thyroid leiomyosarcoma is classified as a member of the
smooth muscle tumors of thyroid glands.5 Up to now,
leiomyosarcomaofthethyroidglandhasbeendescribedin
23 cases3,6---25 in English literature. It is difficult to make
a preoperative diagnosis of thyroid leiomyosarcoma and
differentiateit fromanaplastic thyroidcarcinoma.1,15 The
prognosisofthistumorispoor.Ithasbeenshownthat
aggres-sivesurgery,adjuvantradiotherapy,andchemotherapyhave
notbeeneffectiveontherecurring/relapserateorsurvival
ofthedisease.3,7,14,15 Inthisreporttwopatients with
pri-marythyroidleiomyosarcomaarepresentedwiththereview
oftheliterature.
Case
1
A 39 year old malewas admitted withthe complaintsof
weight loss and odynophagia. There was no history of a
previoussystemicdisease.Hehadbeen smokingapackof
cigarettesperdayfor20yearsandconsumingalcoholona
dailybasis.Therewasnohistoryofradiationexposure.
Dur-ingthephysicalexamination,a2-cmnodulewaspalpatedin
theleftthyroidlobe.Thebloodcountvalueswerenormal,
andthepatientwaseuthyroid.
In the thyroid ultrasonography (USG), a 24×26mm
hypoechoicsolidmassintheleftthyroidlobewasobserved.
Computerizedtomography(CT)showedahypodense
nodu-lar mass with dystrophic calcification in the left thyroid
lobe(Fig.1).Additionally,multiplemetastaticnoduleswere
presentinthelungs(Fig.2).AUSGguidedfineneedle
aspi-rationbiopsyforthethyroidwasnotdiagnostic.Uponthat,
surgicalexplorationofthethyroidbedwasperformedand
the frozen examination from the incisional biopsy taken
from the thyroid tissue yielded a malignant spindle-cell
tumor.
Figure1 CTscanofthefirstpatient,showinganodularmass
withdystrophiccalcification.
Histologicalexamination of thespecimenshowed
spin-dle cell tumor with highly cellular fascicles. The tumor
infiltrated the adjacent fat and striated muscle. 5---10
mitoses/10HPFwerecounted.
Immunohistochemicalstudiesshowedpositiveresultsfor
vimentin,actin,anddesminintumortissue,whereasother
Figure 2 Multiple intraparenchymal and subpleural
Figure3 (a,b)PhotomicrographofCase1,showingspindlecelltumorarrangedinfascicularpatternwitheosinophiliccytoplasm
(hematoxylinandeosin×100,×400).(c)Tumorcellsshowingdiffuseactinpositivity(×200)and(d)focaldesminpositivity(×400).
markersincludingpan-cytokeratin,thyroglobulin,andTTF-1
werenegative(Fig.3a---d).
Surgery was not planned because of the presence of
metastatic disease. Instead, radiotherapy as a palliative
treatmentwasplannedandwasapplied.The patientdied
three months after his first visit because of diffuse
pul-monarymetastasis.
Case
2
A72year-oldfemalewasadmittedwiththecomplaintsofa
rapid-growingmassintheneckanddifficultyinbreathing.
Withanaimtoprovideairwayforthepatient,tracheotomy
wasperformedurgently.IntheneckandthoraxCT,an
infil-trativemasswasobserved,originatingfromtherightthyroid
lobe (Fig.4).The lesion spread uptothe extracapsullary
area,extendedtothehyoidbone,andfilledthethirdand
fourthnecklevelscompletely.Ithadirregularborders,and
included circular calcifications.The mass surrounded and
infiltratedtherightcommoncarotidartery,depressedthe
trachea,andnarrowedtheairway.Ontherightupperjugular
area,thereweremultiplelymphnodes.InthoraxCT,there
were many metastatic nodules present in the lungs, the
largestofwhichwas29mm.Incisionalbiopsywasperformed
duringthetracheotomy.The tumor consistedof
prolifera-tionfavoringamalignmesenchymaltumor.Thetumorcells
hadhyperchromaticnucleiand10---15mitoses/10HPFwere
Figure4 CTscanofthesecondpatient,showingan
infiltra-tivemassintheright thyroidlobe.Tracheotomy tubeisalso
seeninthesection.
observed.Normalthyroidtissuewasobservedinnoneofthe
areas.Immunohistochemically, pan-keratin, thyroglobulin,
andS100werenegativeintumorcells, whereasvimentin,
desmin,andsmoothmuscleactinwerefoundtobepositive
(Fig.5a---d).Additionalsurgerywasnotconductedbecause
themasswasevaluatedasclinicallyandradiologically
unre-sectable.Thepatientdiedduetoimpairedgeneralcondition
718 S¸ahinM˙Ietal.
Figure5 (a,b)PhotomicrographofCase2,showingspindlecelltumorsimilartoCase1(hematoxylinandeosin×100,×200).
(c)Tumorcellsshowingdiffuseactinpositivity(×200)and(d)focaldesminpositivity(×400).
Discussion
Primarysarcomasofthethyroidglandareextremelyrare.1
Amongallof thetumorsofthethyroidgland,
leiomyosar-comaaccountsfor0.014%.6Leiomyosarcoma,whichbelongs
tothegroupofsmoothmuscletumors,ispresentin23cases
intheliteraturetodate.3,6,25 The agesofthecasesinthe
literature vary between 43 and 90, (except a 6-year-old
patientwhohadimmunesystemdeficiency)andthemean
ageof thosepatients was61.4 (Table1). The agesofthe
presentcaseswere39and72respectively.
The etiology of those tumors is unclear; however, it
is thoughtthat theydevelop from thesmooth muscles of
the veinsin the thyroid gland.3,6,7 It is also claimedthat
leiomyosarcoma may develop as a result of smooth
mus-cle metaplasia in a thyroid anaplastic carcinoma.9 The
researcherswho investigated the thyroid leiomyosarcoma
in a 6-year-old immune deficient child claim that this
tumordevelopedduetoamalignanttransformationofthe
smooth muscles, after being infected with Epstein---Barr
virus(EBV).12
The initialsymptom of alladult casesin theliterature
was mainly a rapidly growing mass in the neck. In
addi-tion,itwasreportedthatthreeofthecasessufferedfrom
weightloss,fourhaddysphagiaandodynophagia,threehad
dysphonia,twohadpaininthearm,onehadnewly
occur-ringcough, andone hadbreathingproblems. The present
report’ssecondpatientpresentedwithrapidlygrowingmass
in theneckandbreathingproblems. Thefirstpatient
suf-feredfromodynophagiaandweightloss.
The initial physical examination finding was anterior
neck massin 19of the reported23cases,9 which maybe
explained byrapid tumor growth. Lymph node metastasis
were detected in two patients,3,8 and an unilateral vocal
cordparalysiswasdetectedinoneofthese23patients.7
Thereviewoftheliteratureintermsofdistantmetastasis
revealed that nine of the 23 patients had distant
metas-tases,which weredetected at theinitial examinationsor
duringfollow-ups.Inthepresentpatients,lungmetastasis
wasobservedbytheinitialthoraxCTs.Anaplasticcarcinoma
of the thyroid tendsto causemetastasis to lymphnodes,
whileleiomyosarcomararelydevelopscervicalmetastasis.15
In the cases presented in the literature, the tumors
observedintheultrasonography(US)hadsmoothbordersor
wereirregularlyhypoechoicwithouthalo,hadcysticparts,
were solid,andin some caseswerecalcified masses.7,9---11
In theCTs,themasses involvedlarge necrosisareas,with
or without calcification.6,10,11 Takayama etal.,who
inves-tigated the MRI findings of a case diagnosed as thyroid
leiomyosarcoma,assertedthatthetumor wasobservedto
be isointense withmuscle tissue in the T1 view, while it
wasobserved withmedium intensity inthe T2view. They
alsostatedthatitrevealedmildsignalincreasein
leiomyosarcoma:
presentation
of
two
cases
and
review
of
the
literature
719
Table1 Tablesummarizingthe23casesintheliteratureandthetwopatientsinthisreport.
Reference Age Sex Initialcomplaint Tumorsize (cm)
Lymphnode metastasis
Distant metastasis
Therapyapplied Follow-up Adachi 74 F Massongoingfor4months,pain 12 + + Chemotherapy DWD,1month Kawahara 82 M Amassongoingfor1month,
dysphonia
5.5 − − Lobectomy+neckdissection DWD,4months,localrecurrence
Kawaguchi 54 F Mass ? ? ? Lobectomy Alive,15months,NED Kaur ? ? ? ? + ? ? Alive,12months,LNMet. Chetty 54 F Nosymptoms 3.5 ? ? Lobectomy Alive,15months,NED Iıda 72 F Amassongoingfor7months 3 − − Lobectomy+neckdissection DWD,51months,metastatic
disease
Thompson 64 F Mass 7.5 ? + Uncompletedsurgery DWD,5months,metastatic disease
Thompson 45 M Amassongoingforamonth 9 ? + Lobectomy,chemotherapy Alive,11months,metastatic disease
Thompson 68 M Mass,dysphonia 1.9 + Uncompletedsurgery DWD,18months,metastatic disease
Thompson 83 M Rapidgrowingmass,dysphagia 5.5 + Surgery DWD,3months,metastatic disease
Ozaki 58 F Mass 5 − − Totalthyroidectomy+neck
dissection
Alive,25months,NED Tulbah 6 M Mass 5 − + Tumorectomy Nofollow-upafter4months,
metastaticdisease Tsugawa 90 F Breathingdisorder,amass
growingin1month
8 Partialtumorectomy, tracheotomy
DWD,2months,pneumonia Takayama 66 F Amasswhichwaspresentfor6
yearsthatgrewrapidlyin2 months
8.5 − ? Thyroidectomy,laryngectomy Alive,3months,metastatic
disease,localrecurrence Day 43 M Amassthatgrewin2months 6 − + Thyroidectomy,modifiedradical
neckdissection,adjuvant imatinibmesylatechemotherapy
DWD,6months
Just 83 F Mass,paininthearm 6.7 ? − Biopsy+palliativetherapy(?) DWD,2months,regionalspread
Mansuri 63 F Mass,weightloss,dysphagia 7 ? + Totalthyroidectomy DWD,5months Wang 65 F Mass,weightloss,cough 8 − − Totalthyroidectomy,bilateral
neckdissection+chemotherapy
DWD,4months Qin --- --- --- --- --- --- ---
---Mouaqit 65 M Leftarmpain 9 − − Totalthyroidectomy,partial
esophagectomy
Aliveafter5yearsfollow-up Amal 72 F Neckmasswithskinfistulae 8.5 − --- Leftthyroidlobectomywithmass
excision
DWD,2months Tanboon 64 F --- --- − + Totalthyroidectomy DWD,3months
Ege 56 M Neckmass,dysphonia,dysphagia 3 − − Totalthyroidectomy+central
neckdissection
DWD,8months
Case1 39 M Weightloss,dysphagia 2.6 − + Biopsy+palliativeradiotherapy DWD,3months,metastatic
disease
720 S¸ahinM˙Ietal.
tumorshadsimilarappearanceintheMRI.Itisrealizedthat thyroidleiomyosarcomaisnotverydifferentfromother thy-roidtumorsradiologically.Inthefirstcasepresentedinthis report,alesion intheleftthyroid lobe,cysticareas,and solidnodulesthatincludecalcificationswerefound inthe US.TheCTfindingsrevealedthatthismasswashypodense anddystrophiccalcificationswerepresentinit.Inthe sec-ondcasereported,alesionthatcompletelyobliteratedthe right thyroidlobe wasdetectedin the CT.The lesionhad irregularborders andcircularcalcifications,and was infil-trativetothesurroundingtissues.
Aslightincreaseinthethyroidstimulatinghormone(TSH) levelwasobservedinonepatientintheliterature;14thyroid
functiontestsoftheotherreportedpatientswerenormal,
andthepatientspresentedherewerealsoeuthyroid.
AnUSguidedfineneedleaspirationbiopsyrevealed
pro-liferation of atypical fusiform cells, favoring spindle cell
anaplasticthyroidcarcinoma,medullarythyroidcarcinoma,
ormalignantmesenchymal tumor.Withtheobservationof
atypicalfusiformcells,itwasreportedthatinadditionto
medullarythyroidcarcinomaandthefusiformcelledversion
of anaplastic thyroid carcinoma, spindle epithelial tumor
withthymus-like differentiation (SETTLE), solitary fibrous
tumor, fibrosarcoma,andsynovial sarcoma shouldalsobe
consideredfordifferentialdiagnosis.
Theserumcalcitoninlevelsofthepatientspresentedin
thisreportwerewithinnormal limits.Therefore,the
pos-sibilityofmedullarythyroidcarcinomavanished.However,
discardinganaplasticthyroid carcinomainthe differential
diagnosisismoredifficult;thespindlecelltypecouldbe
mis-diagnosedassarcoma.1Necrosisandcysticdegenerationare
observedfrequently in both leiomyosarcomaand
anaplas-tic thyroid carcinomas. For exact pathological diagnosis,
immunohistochemicalexaminationandelectronmicroscopy
isveryhelpful,7,18althoughthelattercannotbeperformed
routinelyindailyclinicalpractice.
Immunohistochemically, cytokeratin staining shows
epithelial origin and vimentin staining shows
mesenchy-mal origin.26 While leimyosarcomas react positively with
vimentin, muscle specific actin, and desmin, they do
not react with keratin, thyroglobulin, chromogranin, and
calcitonin.6The immunocytochemicalprofile ofanaplastic
carcinomais somewhatvariableand nonspecific,although
is often positive for cytokeratin.27 The spindle cell
vari-ant of anaplastic carcinoma can be differentiated from
sarcomawith positive cytokeratinstaining.28 In the cases
presented,thefactthatnegativestainingofthetumorwith
thyroglobulin,TTF-1,andkeratin,andthatpositivestaining
was observed with vimentin and actin in the first case
specimen,ledtotheimmunohistopathologicaldiagnosisof
leiomyosarcoma.The second casewasdiagnosedwiththe
samemethodasinthespecimen;thetumorwasnegatively
stainedbykeratin,S100,andthyroglobulin,andpositively
stainedbyvimentin,desmin,andsmoothmuscleactin.
Primarysofttissueleiomyosarcomasmayrarely
metasta-sizetothethyroidgland.Forthepatientspresentedinthis
report,thefactthattherewasnootherfocusinthe
radio-logicalexaminationsand noprevious historyofsurgery or
malignancydiscardedthatpossibility.
Although there are various approaches for treatment,
from aggressive surgery to adjuvant radiotherapy and
chemotherapy, it was reported that none of these had
an effect on the recurring rate of the disease or
survival.3,7,14,15 The surgical approaches suggested in the
literaturevaryfromthyroidlobectomy tototal
thyroidec-tomyplusextendedneckdissection.Becauseofthelocally
invasive characteristic of the tumor, some authors
sug-gestradicalsurgeryinordertoobtain localcontrolofthe
disease.11,15,18 There are also cases that had no surgical
resectionofthetumor,asintheabovepresentedcasesthat
didnotundergosurgicaltumorexcision.
Chemotherapyis an alternative method of treatment,
although it is being far from beneficial. Because of the
over expression of the tyrosine kinase receptor c-kit in
thyroidleiomyosarcomas,tyrosinekinaseinhibitorssuchas
imatinib mesylate are thought to bea stepof the
treat-mentapproach.The patientwhowastreatedwithsurgery
plus imatinib mesylate died six months after diagnosis.15
Wangetal.23 presented acasewithleiomyosarcoma,who
underwentthyroidectomyplusanteriorneckdissectionand
receivedadditionaltreatmentofifosfamideandadriamycin,
whoseprognosisandoutcomewerenotreported.Also,asan
additionaltreatment,adjuvant radiotherapymightreduce
theriskoflocalrecurrence.18
The prognosis of the patients withthyroid
leiomyosar-comaispoor.Thediseaseismostlyfatalandsurvivalrates
are reported tobe 5---10% in the first year.17 The reports
in the literature indicate that 14 of the 23 patients died
within monthsdue to thedisease; four of theseven who
survivedhadarecurrentand/ormetastaticdisease.Among
these,thelongestdurationofthepatienttobedisease-free
isfiveyears(Table).Thedurationbetweentheemergence
ofcomplaintsanddeathwasafewmonthsforbothpatients
presentedinthisreport.
In conclusion, although it is a rare malignancy of the
thyroid,leiomyosarcomamustbetakenintoconsideration,
especially inthe patients presenting withrapidly growing
massattheanteriorportionoftheneckanddistant
metas-tasis.Immunohistochemistryisnecessarytodifferentiateit
fromotheraggressivethyroidmalignancies,suchas
anaplas-ticthyroidcarcinoma.Leiomyosarcomaofthethyroidisan
aggressive tumor and has a poor prognosis; the necessity
of an aggressive oncological and surgical approachis still
controversial.
Conflicts
of
interest
Theauthorsdeclarenoconflictsofinterest.
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