INTRODUCTION
Perio perative fro z en sectio ns have been used by patho lo g ists fo r mo re than a hundred ye a rs b ut this me tho d o nly b e c a me w id e ly applied with the develo pment o f the cryo stat in 1 9 5 0 . Initially, it was fo und useful in breast tumo r surg ery b ut its use ha s b een widened to the diag no sis o f o ther lesio ns in o ther o rg ans.
This diagno stic alternative is especially useful when data canno t be o btained o n the histo lo gical pa tte rns o f dise a se s in o rg a ns tha t a re o nly a c c essib le b y surg ery, a nd when the type o f treatment is based o n patho lo gic findings. Diseases that arise as nodules in salivary glands or the thyroid are examples that can illustrate this situatio n.
As early as 1 9 5 8 , Pitts et al1 hig hlig hted the patho lo g ist’s difficulties in reaching the rig ht dia g no sis fo r sa liva ry g la nd tumo rs a nd this difficulty was also mentio ned by o ther autho rs like N akasawa et al2 in 1 9 6 8 and Didz ans & VanN o strand3 in 1 9 8 4 .
The minima l re c o mme nd e d surg ic a l a p p ro a c h to p a ro tid tumo rs is p a rtia l paro tidecto my with resectio n o f the superficial lo be o f the g land. Histo lo g ic diag no sis prio r to surg ery is no t p o ssib le , a s inc isio na l b io p sie s a re co ntraindicated due to the po ssibility o f facial
Pe riope rative froze n se ction
e xamination in parotid gland tumors
Head and Neck Surgery Service of Heliópolis Hospital, São Paulo, Brazil
Marcos Brasilino de Carvalho, João Marcos Arantes Soares Abrão Rapoport, Josias de Andrade Sobrinho Antonio Sérgio Fava, Jossi Ledo Kanda Carlos Neutzling Lehn, Fernando Walder Marcelo Benedito Menezes, Sérgio Luiz Coelho Negri
ABSTRACT
CO N TEX T: The minimal reco mmended surg ical appro ach to paro tid tumo rs is partial paro tidecto my with resectio n o f the superficial lo be o f the g land. Histo lo g ic diag no sis prio r to surg ery is no t po ssible, as incisio nal bio psies are
co ntraindicated due to the po ssibility o f facial nerve injury o r inco mplete tumo r resectio n. Thus, the bio psies tend to be perio perative.
O BJECTIV E: To co mpare the results o f fro z en sectio n examinatio n with the definitive patho lo g ical diag no sis.
DESIGN : Accuracy study by retro spective analysis.
Setting: Head and N eck Surg ery Service o f Helió po lis Ho spital, São Paulo , Braz il.
SAM PLE: 1 5 3 cases o f paro tid g land tumo rs treated between 1 9 7 7 and 1 9 9 4 .
DIAGN O STIC TEST: Fro z en sectio n and patho lo g ical diag no sis.
M AIN M EASUREM EN TS: Sensibility and specificity o f the fro z en sectio n examinatio n.
RESULTS: Fro z en sectio n study diag no sed 1 9 (1 2 .4 %) malig nant and 1 2 7 (8 3 .7 %) benig n tumo rs. Sensitivity o f the fro z en sectio ns fo r malig nancy was 6 1 .5 % (9 5 % CI 5 4 to 6 9 %) and specificity was 9 8 % (9 5 % CI 9 4 to 1 0 0 %), and this result is co mparable to the literature.
CO N CLUSIO N S: W e co nsider that fro z en sectio n examinatio n fo r salivary g land tumo rs is no t sufficient o n its o wn fo r deciding o n the best manag ement. Their
interpretatio n must be co rrelated with clinical and intrao perative finding s, in asso ciatio n with the surg eo n’s experience.
KEY W O RDS: Fro z en sectio n. Head and N eck tumo rs. Paro tid g land tumo rs. Salivary g land tumo rs
nerve injury o r inco mplete tumo r resectio n. Thus, the bio psies tend to be perio perative.4 ,5 ,6
Unlike salivary g land tumo rs o f the o ral cavity, in which a simple inspectio n o f the lesio n by an experienced examiner can stro ng ly sug g est the benig n o r malig nant nature o f the disease,7 in e a rly p a ro tid tumo rs c linic a l e vid e nc e o f ma lig na nc y usua lly c a nno t b e fo und , a nd ima g ing metho ds a nd fine needle a spira tio n bio psy (FN AB) have limitatio ns in making this differentiatio n.8 ,9 In this way, the decisio n o n the extent o f surg ery must in many cases be made in the o perating theater based o n fro z en sectio n examinatio n and o n the surg ical finding s.
W ith the o b je c tive o f e va lua ting the imp o rta nc e o f fro z e n se c tio ns in surg ic a l dec isio ns, we retro spec tively a na lyz ed c a ses tre a te d b y p a ro tid e c to my in o ur se rvic e , co mparing the fro zen sectio n diag no sis to clinical and surg ical finding s and o perating decisio ns.
METHODS
A retro spective analysis was made o f 1 5 3 cases o f paro tid g land tumo rs treated at the Head and N eck Service o f Helió po lis Ho spital, São Paulo , Brazil, between 1 9 7 7 and 1 9 9 4 . The ages rang ed fro m 8 to 8 4 years and there were 7 0 men and 8 3 wo men. The results o f fro zen sectio n examinatio n were co mpared with the definitive patho lo g ic diag no sis. Sensitivity and specificity o f fro zen sectio n examinatio n fo r malignancy were calculated as fallo ws: Sensitivity = nm/ (nm + nib) and Specificity = nb/ (nb + nin), where nm = number o f cases identified co rrectly as malig nant; nib = histo lo g ic a lly ma lig na nt c a se s w ith inco nclusive o r benig n result at fro zen sectio n; nb = number o f cases identified co rrectly as benig n; a nd nin = histo lo g ic a lly b e nig n c a se s w ith inco nclusive o r malig nant result at fro zen sectio n.
RESULTS
Fro z en sectio n examinatio n identified 1 2 8 benig n cases (8 3 .7 %), 1 9 (1 2 .4 %) malig nant and in 6 (3 .9 %) was inco nclusive. The definitive p a tho lo g ic d ia g no sis sho w e d 2 6 (1 7 % )
malig nant cases and 1 2 7 (8 3 %) benig n cases. Co mparing the perio perative result with definitive diag no sis, 1 0 % (1 6 / 1 5 3 ) were true po sitive, 8 1 % (1 2 4 / 1 5 3 ) true neg ative, 2 % (3 / 1 5 3 ) false po sitive, 7 % (1 0 / 1 5 3 ) false neg ative, 1 7 % (9 5 % CI 1 1 to 2 3 ) prevalence, 8 4 % (9 5 % CI 7 8 to 9 0 ) po sitive predictive value, 9 3 % (9 5 % CI 8 8 to 9 7 ) neg ative predictive value, 2 6 .0 5 po sitive likeliho o d ratio and 0 .3 9 neg ative likeliho o d ratio . Thus, the sensitivity fo r malig nancy was 6 1 .5 % (9 5 % CI 5 4 to 6 9 ) and the specificity was 9 8 % (9 5 % CI 9 5 to 1 0 0 ) (Table 1 ).
In the seven cases o f benign disease in which the fro zen sectio n results were inco nclusive o r false po sitive, no extended surg ical pro cedure o r facial nerve sacrifice was perfo rmed, as the surg eo n’s clinical impressio n prevailed (clinical histo ry plus macro sco pic perio perative finding s). Amo ng the ten cases o f malignant disease in which the fro zen sectio n results were inco nclusive o r false negative, there was preo perative facial palsy in five o f them, a previo us patho lo g ical study o r po sitive FN AB fo r malig nancy in three cases, and tumo r invasio n o f the fa cia l nerve in five ca ses, thereb y no t allo wing co nservative dissectio n (Table 2 ).
DISCUSSION
Saltzstein & N ahum1 1 in 1 9 7 3 emphasized tha t the o nly ind ic a tio n fo r fro z e n se c tio n e xa mina tio n w a s the ne e d fo r d e c isio ns o n immediate actio ns. This sho uld therefo re no t be ro utinely used witho ut kno wing its real benefit. Ag reeing with W inship & Ro svo ll,1 2 they believed that a clo se discussio n between patho lo g ist and surgeo n is fundamental in o btaining highly reliable final results. Cro ss et al1 3 stated that the ro le o f fro z en sectio ns in diag no sis and treatment o f salivary gland lesio ns was still no t well established. Hillel & Fee1 4 and Rig ual et al1 5 stressed that the surg eo n’s capability o f assessing fro zen sectio n results is very impo rtant in avo iding iatro g enic pro blems. G ranick et al1 6 sug g ested that the best g uide fo r decisio ns was the surg ical finding s.
fro m o ther salivary g land tumo rs. W hen o nly ma lig na nt tumo rs a re a na lyz ed, the surg eo n sho uld decide the extent o f the pro cedures, and the sampling pro blems are mo re evident. Results fro m o the r a utho rs using fro z e n se c tio ns in malig nant salivary g land tumo rs are similar to o urs(Tables 1 and 3 ).1 -3 ,8 ,1 3 -2 0
In o ur series there was a sensitivity o f 6 1 .5 % and specificity o f 9 8 % fo r malig nancy diag no sis. The patho lo g ical diag no sis o f the salivary g land tumo r is d iffic ult e ve n fo r e x p e rie nc e d patho lo g ists. W hen the patho lo g ist is no t sure abo ut the diag no sis he may be inclined to g ive an inco nclusive o r benig n diag no sis because he is afraid o f the co nsequences o f a misdiag no sis fo r the pa tient. O n the o ther ha nd, a wro ng d ia g no sis o f b e nig n tumo r usua lly le a d s to co mplementary pro cedures that can minimize the c o nse q ue nc e s o f e rro r. Thus, the ra te s o f specificity fo r malig nancy increase because the diagno sis o f a malignant tumo r is o nly established when the patho lo g ist is sure abo ut it. Ho ffmann e t a l2 1 re p o rte d d o ing fro z e n-se c tio n histo patho lo g ical analysis to determine whether the tumo r was malig nant and, if it was a hig h-g rade tumo r, to identify whether the neo plasm was a lympho ma, and fo r analyz ing suspicio us lymph no des. Eisele et al2 2 co nsidered that, if a
definite diag no sis o f malig nancy co uld no t be ma d e b y fro z e n se c tio n a sse ssme nt, furthe r surg e ry sho uld b e d e fe rre d until a fina l histo patho lo g ical diag no sis was o btained.
In o ur c a se s no ma jo r p ro c e d ure w a s perfo rmed in false po sitive cases because in the surg eo n’s o pinio n the resectio n was adequate and there was no facial nerve invasio n. Amo ng the 1 0 false neg ative o r inco nclusive cases, in 9 o f them there were clinical finding s that sug g ested malig nancy o r a po sitive FN AB fo r malig nant cells o r intrao perative malig nant characteristics. Thus, the surg ical pro cedure was suitable fo r the c a se s. M e g e ria n & M a nig lia2 3 in 1 9 9 4 sug g ested that FN AB mig ht be co mplementary to fro z en sectio ns. This has been studied in o ur service fo r salivary g land tumo rs and merits future publicatio n.
In this series the sensitivity fo r malig nancy was 6 1 .5 % and the specificity was 9 8 %. These re sults must b e inte rp re te d c a re fully b y the surg eo n in asso ciatio n with the clinical histo ry and surg ical finding s. In this way, the po ssibility fo r erro rs will be decreased, especially if the surg eo n discusses each case with the patho lo g ist in the o perating theater, so as to bro aden the data o n the case and impro ve the sensitivity o f the diag no sis.
Ta ble 1 - Definitive a nd periopera tive (frozen section) dia gnosis
Benig n (histo lo g ically) Fro zen sectio n Malig nant (histo lo g ically) Fro zen sectio n
Pleo mo rphic adeno ma 8 1 (b=7 8 , m=0 3 ) Adeno carcino ma 6 (b=0 1 , m=0 4 , i=0 1 )
W arthin’s tumo r 1 7 (b=1 6 , i=0 1 ) Squamo us cell carcino ma 6 (b=0 1 , m=0 4 , i=0 1 )
Inflammato ry reactio n 8 (b=0 8 ) Muco epidermo id carcino ma 4 (b=0 1 , m=0 3 )
Lympho reticular hyperplasia 6 (b=0 5 , i=0 1 ) Adeno id cystic carcino ma 3 (b=0 2 , m=0 1 )
Salivary g land cyst 5 (b=0 5 ) Undifferentiated carcino ma 3 (b=0 2 , m=0 1 )
Mo no mo rphic adeno ma 3 (b=0 3 ) Lympho ma 1 (m=0 1 )
Acinic cell adeno ma 2 (b=0 2 ) Malig nant mixed tumo r 1 (m=0 1 )
Lipo ma 1 (b=0 1 ) Melano ma 1 (m=0 1 )
Basalo id adeno ma 1 (b=0 1 ) Acinic cell carcino ma 1 (b=0 1 )
G land hypertro phy 1 (b=0 1 ) Mixo id tissue 1 (b=0 1 )
Reactio nal lympho id hyperplasia 1 (b=0 1 )
TOTAL 1 2 7 TOTAL 2 7
b=1 2 2 (9 4 .5 %); m=0 3 (2 .3 %); i=0 2 (3 .2 %) b=0 9 (3 0 .8 %); m=1 7 (6 1 .5 %); i=0 2 (7 .6 %)
CONCLUSION
Fro z en sectio ns fo r paro tid tumo rs are o n the ir o w n insuffic ie nt fo r ma king ra d ic a l decisio ns.
REFERENCES
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Ta ble 2 - Fa lse nega tive or inconclusive ca ses of ma ligna nt neopla sms from frozen section ex a mina tion
Case Clinical Histo ry FSF Surg ery Histo lo g ical Diag no sis
1 Facial palsy and FN AB Inco nclusive Resectio n o f the lesio n Squamo us cell carcino ma
po sitive fo r malig nancy with po sitive marg ins
2 Previo us patho lo g ical diag no sis Benig n Partial paro tidecto my with Squamo us cell carcino ma
o f squamo us cell carcino ma preservatio n o f the facial nerve
3 Facial palsy plus previo us patho lo g ic Inco nclusive To tal paro tidecto my Adeno carcino ma
diag no sis o f squamo us cell carcino ma
4 Facial palsy Pleo mo rphic To tal paro tidecto my with Adeno carcino ma
adeno ma reco nstructio n o f the facial nerve
6 Patient with no malig nant sig nals Benig n Partial paro tidecto my and facial Undifferentiated carcino ma
nerve reco nstructio n
7 Fixed tumo r with skin invasio n Benig n To tal paro tidecto my with Undifferentiated carcino ma
po sitive marg ins
8 Facial palsy Benig n To tal paro tidecto my with sacrifice Adeno id cystic carcino ma
o f facial nerve branches
9 Previo us surg ery and radio therapy Benig n To tal paro tidecto my with Adeno id cystic carcino ma
witho ut patho lo g ic diag no sis; sacrifice o f facial nerve
recurrent facial tumo r
1 0 Paro tid tumo r with previo us Benig n To tal paro tidecto my with sacrifice Acinic cell carcino ma
bio psy o f acinic cell carcino ma o f facial nerve. N erve and skin
macro sco pic invasio n
FSF = Fro zen Sectio n Finding s
Ta ble 3 - Results of frozen section ex a mina tion for
ma ligna nt tumors of sa liva ry gla nds
Autho r N Sensitivity (%) Specificity (%)
Rig ual et al1 5 2 3 9 0 9 6
Cro ss et al1 3 1 0 9 0 9 8
* G ranick et al1 6 5 2 8 2 9 7
* Didzans & VanN o strand 3 2 0 8 5 9 8
Pitts et al 1 7 8 5
--N akazawa et al2 1 9 8 4 .2
--W heelis & Yaring to n1 7 5 2 8 8 9 8
Chann et al1 8 1 3 7 0 1 0 0
* * Heller et al8 4 5 6 9 9 6
* Miller et al1 9 2 5 6 0 9 4
* Hillel & Fee1 4 1 4 4 3 9 5
Co hen et al2 0 3 0 9 2
Carvalho et al (present study) 2 6 6 1 .5 9 8
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18. Chann MKM, McGuire LJ, King W, Li AKC, Lee JCK. Cyto diagno sis o f 112 salivary gland lesio ns: co rrelatio ns with histo lo gic and fro zen sectio n diagno sis. Acta Cyto l 1992;36:353-63.
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M a rcos Bra silino de Ca rva lho - MD. Chief o f the Head and N eck Surg ery Service. Head and N eck Surg ery Service o f Helió po lis Ho spital, São Paulo , Braz il.
Joã o M a rcos Ara ntes Soa res - Ex-resident o f the Head and N eck Surg ery Service o f USMG Clinics Ho spital. São Paulo , Braz il.
Abrã o Ra poport - Head and N eck Surg ery Service o f Helió po lis Ho spital. São Paulo , Braz il.
Josia s de Andra de Sobrinho - Head and N eck Surg ery Service o f Helió po lis Ho spital. São Paulo , Braz il.
Antonio Sérgio Fa va - Head and N eck Surg ery Service o f Helió po lis Ho spital. São Paulo , Braz il.
Jossi Ledo Ka nda - Head and N eck Surg ery Service o f Helió po lis Ho spital. São Paulo , Braz il.
Ca rlos N eutzling Lehn - Head and N eck Surg ery Service o f Helió po lis Ho spital. São Paulo , Braz il.
Ferna ndo W a lder - Head and N eck Surg ery Service o f Helió po lis Ho spital. São Paulo , Braz il.
M a rcelo Benedito M enezes - Head and N eck Surg ery Service o f Helió po lis Ho spital. São Paulo , Braz il.
Sérgio Luiz Coelho N egri - Head and N eck Surg ery Service o f Mário Pena Ho spital. São Paulo , Braz il.
Sources of funding: N o t declared
Conflict of interest: N o t declared
La st received: 1 0 March 1 9 9 9
Accepted: 1 3 May 1 9 9 9
Address for correspondence:
Marco s Brasilino de Carvalho Pça. Amadeu Amaral 4 7 - cjto . 8 2 São Paulo / SP - Brasil - CEP 0 1 3 2 7 -0 1 0 E-mail: sccphh@ uo l.co m.br
RESUMO
CO N TEX TO : O pro cedimento cirúrg ico mínimo g eralmente aceitável para a abo rdag em de tumo res de paró tida é a paro tidecto mia parcial co m retirada do lo bo superficial da g lândula. Há uma impo ssibilidade de se ter o diag nó stico prévio histo ló g ico da lesão antes do pro cedimento cirúrg ico , po is bió psias incisio nais são co ntra-indicadas pela po ssibilidade de secção inadvertida de ramo s do nervo facial e ressecção inco mpleta da lesão . Assim, a bió psia é co mumente intracirúrg ica.
O BJETIV O : Co mparar o s resultado s do exame anato mo pato ló g ico intra-o perató rio po r co ng elação co m o s resultado s do diag nó stico definitivo através do exame de parafina. TIPO DE ESTUDO : Estudo exato pela análise retro spectiva. LO CAL:
Serviço de cirurg ia de Cabeça e Pesco ço do Co mplexo Ho spitalar Helió po lis, São Paulo , Brasil. TESTE DIAGN Ó STICO :
Exame anáto mo pato ló g ico intra-o perató rio po r co ng elação e exame po r parafina. VARIÁV EIS ESTUDADAS: Sensibilidade e especificidade do exame po r co ng elação . RESULTADO S: Ao exame po r co ng elação , em 1 9 caso s (1 2 ,4 %) o diag nó stico fo i de neo plasia malig na e em 1 2 8 (8 3 ,7 %) o diag nó stico fo i de tumo r benig no . A sensibilidade para malig nidade fo i de 6 1 ,5 % e a especificidade fo i de 9 8 %. Esses resultado s são equivalentes ao s referido s na literatura. O s resultado s falso -po sitivo s o u neg ativo s não interferiram na co nduta ado tada -po is, para a decisão do tratamento , fo i co nsiderado o co njunto de dado s clínico s, achado cirúrg ico e anáto mo pato ló g ico . CO N CLUSÕ ES: O exame po r co ng elação para o s tumo res da g lândula salivar, empreg ado iso ladamente não é suficiente para decidir a melho r co nduta, e sua interpretação deve ser feita co rrelacio nando o s achado s clínico s e intra-o perató rio s, asso ciado s à experiência do cirurg ião .
