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Case Report
REVISTA PAULISTA DE MEDICIN ABronchial oncocytoma
Faculty of Medicine, Santa Casa de Misericórdia de São Paulo,
Universidade de São Paulo, São Paulo, Brazil
a b s t r a c t
CO N TEX T: O nc o c yto ma s a re g e ne ra lly sma ll a nd pre se nt slo w g ro wth. Finding o f the tumo r usually o ccurs incidentally. Their inci-dence is hig her amo ng male patients. O nco cyto mas in muco us bro n-chial g lands are extremely rare.
CASE REPO RT: A 3 5 yearo ld male who presented bro nchial o nco -cyto ma. The tumo r was fo und after bro ncho sco py that investig ated an atelectasis o f the upper left lo be. Histo lo g ical examinatio n with o ptical micro sco py revealed a mature neo plasm fo rmed by o vo id cells with thin, g ranular, eo sino philic cyto plasm and small nuclei similar to o nco cytes. Electro n micro sco py sho wed mito cho ndrial hyperplasia. A three-year fo llo w-up after tho raco to my fo llo wed by lo becto my and remo val o f the bro nchial tumo r was uneventful.
KEY W O RDS: O nco cyto ma. Bro nchial. Pulmo nary.
• Renata Telles Rudg e de Aquino • Maria Elisa Ruffo lo Mag liari • Ro berto Saad Junio r • Vicente Do rg an N eto • Jo rg e Ethel Filho • Carlo s Dandretta N eto • Vera Luiz a Capelo z z i
INTRODUCTION
Onco cyto mas are rare, usually benign tumo rs fo rmed by altered epithelial glandular cells named o nc o c yte s. The se c e lls, whic h we re id e ntifie d b y Hamperl in 1931, present abundant eo sino philic cy-to plasm, co mpo sed o f hyperplastic micy-to cho ndria and no o rganelles.1
A small number o f these cells may be fo und in the epithelium o f the upper respirato ry tract and in muco us glands o f b ro nchi and o ther o rgans. Their incidence increases with age, altho ugh their functio n remains unkno wn. Since cell divisio n is no t prevented by o nco cyte fo rmatio n, it is po ssible that they trigger b enign o r malignant hyperplasias and neo plasms. They may be fo und in tumo rs as iso lated cells playing a relevant ro le o r as their so le co mpo nent.1-3
Jaffé intro duced the term o nco cyto ma in 1932 fo r salivary gland tumo rs fo rmed exclusively o r mainly by o nco cytes. This designatio n has been used ever since, altho ugh names such as o xyphilic adeno ma and mito cho ndrio ma have been suggested. These tumo rs have been fo und later in o ther glandular tissues, such as: thyro id, parathyro id, lacrimal, adeno hypo physis, kidneys, and pancreas, all with very similar features regardless o f the site.1,2-4
Onco cyto mas are generally small and present slo w gro wth. Finding o f the tumo r usually o ccurs inci-d e ntally.5 The ir inc id e nc e is highe r am o ng m ale
patients. Onco cyto mas in muco us bro nchial glands are extremely rare. Fechner and Bentick6
repo rted the first case diagno sed after electro n micro sco py in 1973. Only nine cases have been repo rted since then.2,5,7,8
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CASE REPORT
A 35-year-o ld Hispanic male presented a histo ry o f c o u g h in g an d fe ve r fo r o n e we e k. Ph ys ic al examinatio n and chest X-rays (Figure 1) revealed left upper lo be atelectasis. Bro ncho sco py sho wed a gro wth in the upper left lo be. Bio psy o f the matter presented a c h ro n ic in flam m ato ry p ro c e s s . Co m p u te d to mo graphy was no t ab le to detect the tumo r. He underwent tho raco to my, lo becto my and remo val o f the b ro nc hial tum o r. His thre e - ye ar fo llo w- up was uneventful. The findings o f the patho lo gy specimens were: a) Gross Anatomy: The no dule , with a 1.5 cm d iam e te r, had a sm o o th surfac e . Cro ss- se c tio ns sho wed a yello w-tan firm tissue. b) Microscopic Exami-nation: Multiple sectio ns, stained with hemato xylin-eo sin, sho wed a mature nxylin-eo plasm fo rmed by o vo id cells with thin, granular, eo sino philic cyto plasm and small nuclei, similar to o nco cytes. In so me fields ir-regular glandular patterns were o bserved. A fibro us layer, with a small area o f bro nchial muco sa (Figure 2), limited the no dule. c) Electron Microscopy: Ovo id cells with mito cho ndrial hyperplasia and evident cristae (Figure 3 - Philips - x9500).
DISCUSSION
Diagno sis was reached after electro n micro s-co py, which revealed mito cho ndrial hyperplasia. Many o rgane lle s m ay d e te rm ine granular, e o sino p hilic c yto p las m , whic h m ake s the s truc tural as p e c ts o b served in electro n micro sco py o f mito cho ndrial hyperplasia an impo rtant diagno stic criterio n.6
This case is similar to o ther repo rted cases o f b ro nchial o nco cyto ma in which a tumo r was fo und in a main b ro nchus o f an adult male patient.2 The
main co ncern ab o ut o nco cyto mas is their variab le malignancy po tential. Altho ugh usually benign, there are re po rts o f m alignant o nc o c yto m as in salivary glands, thyro ids, nasal cavities, paranasal sinuses, and the mediastinum.2 Nielsen,7 in 1985, repo rted a
case o f malignant b ro nchial o nco cyto ma with lymph no de metastasis, who se fo llo w-up after two years o f surgical treatment was uneventful. We did no t find any o the r c as e o f b ro nc hial m alig nanc y in the literature.
Th e b io lo g ic al b e h avio r o f p u lm o n ary o nco cyto mas has no t yet been established, due to its rarity. The distinctio n between hyperplasia, adeno ma and carcino ma may be difficult: papillary o nco cyto mas o f the naso pharynx and larynx are usually co nsidered hyperplasias, and the so lid lesio ns arising in salivary
Figure 1. Chest X-ray revealing left upper lobe atelectasis.
Figure 2. Bronchial section showing proliferation of cells with oncocyte features: well-differentiated uniform cells with granular cytoplasm (HE, x100).
Figure 3. Micrograph showing nucleus with more intense electron-density close to nuclear membrane. In the cytoplasm we see many mitochondria, poorly preserved by fixation (formaldehyde), evident mainly by mitochondrial cristae (Philips, x9500).
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1. Hamperl H. Benign and malignant o nco cyto ma. Cancer 1962;15:1019-27.
2. Cwierzyk TA, Glasberg SS, Virshup MA, et al. Pulmo nary o nco cyto ma: repo rt o f a case with cyto lo gic, histo lo gic and electro n micro sco pic study. Acta Cyto l 1985;29:620-3.
3. Fine G, Chang CH. Adeno ma o f type 2 pneumo cytes with o nco cytic features. Arch Patho l Lab Med 1991;115:797-801.
4. Mo rra MN, Das S. Re nal o nc o c yto m a: a re vie w o f histo ge ne sis, histo patho lo gy, diagno sis and treatment. J Uro l 1993;150:295-302.
5. Tashiro Y, Iwata Y, Nabae T, Manabe H. Pulmo nary o nco cyto ma: repo rt o f a c as e in c o njunc tio n with an im m uno his to c he m ic al and ultrastructural study. Patho l Int 1995;45(6):448-51.
6. Fechner RE, Bentinck BR. Ultrastructure o f bro nchial o nco cyto ma. Cancer 1973;1:1451-7.
7. Nielsen AL. Malignant bro nchial o nco cyto ma: case repo rt and review o f the literature. Hum Patho l 1985;16(8):852-4.
8. Kumar PV, Mo nabati A. Bro nchial o nco cyto ma diagno sed by brushing cyto lo gy [Letter]. Acta Cyto l 1998;42(4):1056-7.
REFERENCES
r e s u m o
CO N TEX TO : O nc o c ito ma s sã o tumo res g era lmente peq ueno s e apresentam crescimento lento . A identificação do tumo r usualmente o co rre incidentemente. Sua incidência é maio r entre o s ho mens. O nco cito mas o rig inário s das g lândulas muco sas do s brô nquio s são muito raro s.
RELATO DE CASO : Um paciente de 3 5 ano s do sexo masculino co m o nco cito ma brô nquico . O tumo r fo i o bservado à bro nco sco pia, re a liz a d a p a ra inve stig a ç ã o d e a te le c ta sia d o lo b o sup e rio r esquerdo . O exame histo ló g ico co m micro sco pia ó tica mo stro u neo -p la sia ma d ura fo rma d a -p o r c é lula s o vó id e s c o m c ito -p la sma eo sino fílico fino e g ranular, co m núcleo pequeno , assemelhando -se a o nc o c ito s. A mic ro sc o p ia e le trô nic a mo stro u hip e rp la sia mito c o ndria l. O seg uimento três a no s a pó s a to ra c o to mia c o m lo becto mia e remo ção do tumo r fo i livre de co mplicaçõ es o u recidiva.
PALAVRAS-CHAVE: O nco cito ma. Brô nquico . Pulmo nar.
Re na ta Te lle s Rud g e d e Aq uino , MD, MS c . De partme nt o f Me dicine , Faculty o f Me dical Scie nce s, Santa Casa de Mise ricó rdia de São Paulo , São Paulo , Brazil.
Ma ria Elis a Ruffo lo Ma g lia ri, MD. De partme nt o f Me dicine , Faculty o f Me dical Scie nce s, Santa Casa de Mise ricó rdia de São Paulo , São Paulo , Brazil.
Ro b e rto S a a d Junio r, MD, PhD. Divisio n o f Tho racic Surge ry, Faculty o f Me dical Scie nce s, Santa Casa de Mise ricó rdia de São Paulo , São Paulo , Brazil.
Vic e nte Do rg a n Ne to , MD, PhD. Divisio n o f Tho racic Surge ry, Faculty o f Me dical Scie nce s, Santa Casa de Mise ricó rdia de São Paulo , São Paulo , Brazil.
Jo rg e Ethe l Filho , MD. Divisio n o f Pulm o nary Scie nce s, Faculty o f Me dical Scie nce s, Santa Casa de Mise ricó rdia de São Paulo , São Paulo , Brazil. Ca rlo s Da nd re tta Ne to , MD, PhD. De partme nt o f Patho lo gy, Faculty o f Me dical Scie nce s, Santa Casa de Mise ricó rdia de São Paulo , São Paulo , Brazil.
Ve ra Luiza Ca p e lo zzi, MD, PhD. De partme nt o f Patho lo gy, Faculty o f Me dicine , Unive rsidade de São Paulo , São Paulo , Brazil.
S o urc e s o f fund ing : No t de clare d Co nflic t o f inte re s t: No t de clare d La s t re c e ive d : 02 Fe b ruary 2000 Ac c e p te d : 17 Fe b ruary 2000 Ad d re s s fo r c o rre s p o nd e nc e : Re nata Te lle s Rudge de Aq uino
De partame nto de Me dicina da Santa Casa de São Paulo . Rua Dr. Ce sário Mo tta Jr., 112
São Paulo /SP - Brasil - CEP 01221-020 E-mail: re nata_ aq uino @ ho tmail.co m
p u b lis hin g in fo r m a t io n
glands are co nsidered adeno mas. The need fo r further studies o f this rare entity demands the publishing o f case repo rts. In this repo rt, atypical cells, invasio n o r
metastases were no t o bserved; therefo re, the tumo r was classified as an adeno ma with a benign behavio r, remaining similar to o ther repo rted cases.
