Solitary intraoral keratoacanthorna Report of a Case
THE
CATHOLIC
DEPARTMENTS
MEDI~AI.
(‘ENTER
OF DENTISTRY
OF
AND
~R00tit.~x
AND
~uwrv\.
ti\jc
PA1‘HOLOG’I
The keratoacanthoma is a tumorlike proliferation clinically and microscopically, it may bear close following article discusses the keratoacanthoma intraoral keratoacanthoma.
which is rarely seen In the oral cavity. Both resemblance to squamous-cell carcinoma. The and, in addition, presents a case report of solitary
I
Microscopic
CASE
Histologic sections rcvcalcd a well-delineated raised epthelial lesion exhibiting a shallo\+ central kcratin-filled crate] (Fig. I ). T) pical stratified squamous epithelium extended up to the edge of the lesion. forming an inverted tip which undermined the normal surface (Fig. 2). Here the stratified squamous epithelium became markedly acanthotic and cxhibited numerous glassy-appearing dyskeratotic cells (Figs. 7 and 3) and scattered keratin pearls. This rpithclium extended deeply into the underlyin, cr dense fibrous connective tissue with the formation of broad-based rete ridges. The individual cells ucrc well diffcrcntiatcd and showed minimal mitotic activit) (Fig. 3). The he of the lesion displayed :I welt&lineated margin al the interf;tce with the underlying fibrous connective tiisue, I’orminp a pushing horder and showing nc, e~idcnce of infiltration.
n a previous publication, our laboratory reported what we considered to be the third acceptable case of solitary intraoral keratoacanthoma. ’ The literature was reviewed, and the possible source of histogenesis was discussed. We have since seen another case and present here the fourth report of solitary intraoral keratoacanthoma. REPORT
In December, 1976, a X-year-old woman was relerred to one of us (H. B.) with a soft-tissue growth on the anterior maxilla. Her past medical history was within normal limits. She had been edentulous for 20 years and was wearing heloriginal maxillary denture. The patient’s present illness had begun approximately 3 weeks earlier. when she noticed that her upper denture did not tit well. Clinical examination rc~
description
vealed a I .O by 7.0 cm. raised. granulomatclus-appearing mass attached to the midline of the maxilla in the arca
Diagnosis
Gross
The diagnosis was I\~ratoacanthoma. Although healing uneventful and ntr remaining disease WI\ clinically evdent. it %;I\ dcc~dctl to rc-escisc the surgic;tl :lre;l. This I-e-excision U;IS xl\ ised hecauw ;I l’e\c 01’ the pathology cow stiltants brlicvcd that Itit’ growth tnipht represent ii hilldifferentiated sqt~;~~~iol1s-c~ctI carcinoma. ~rlthough the maior114 agreed that the ICSIOI~ v+as hcnign kcratoacanthonia. C:~OII 0.7 cm., was submitted. The specimen exhibited a central core which was traversed by fissured I’olds. The tissue was sectioned in half, and both pieces were submittetl.
V.;IS
DISCUSSION “Assistant **Assistant ***Attending Warwick, ****Director,
74
Director. Oral Pathology Kesldency Trumng Attending, Division of Oral Pathology. Oral Surgeon, St. Anthony’\ Community N. Y Division
01 Oral
Patholos!
Propran~ Hwpital.
The hcratoacanthotl~~l is il tumorlike proliferatton which. clinically and microscopically, often resembles ~quatnous-cell
carcinoma.
It ordinarily
painless, rapidly appearing crateriforni I to 2 cm. in diameter. which attains
presents
as
a
lesion. usually full size in about 6
Volume Number
Solitary intraoral keratoacanthoma
47 I
Fig. 1. Low-power tion, X 1IJ.X.)
Fig.
2. Medium-power
photomicrograph
photomicrofraph
displaying
showin
the crateriform
appearance
g lip of the lesion
to 12 weeks. Spontaneous healing tends to take place over the next 4 to 6 months, with slight scar formation.’ The exposed parts of the skin, lips, cheeks, nose, and dorsum of the hands are the sites of predilection in the vast majority of cases.:{ As mentioned previously, there was controversy at the time of original diagnosis of this lesion. The differential diagnosis in this particular case was between squamous-cell carcinoma, verruwell-differentiated cous carcinoma, and keratoacanthoma. The possibility of verrucous carcinoma was discarded because of the lack of deep surface clefts filled with parakeratin. According to Lever and Shaumburg-Lever,” the most significant factor in distinguishing between well-differentiated squamous-cell carcinoma and keratoacan-
of the keratoacanthoma.
and keratin
pearl
formation.
75
(Magnifica-
(Magnification,
thoma is the over-all architecture of the lesion. We believe that the characteristic exophytic nature of this growth, its central crater, its deep-pushing border, and the undermining of the normal stratified squamous epithelium at its margin justified the diagnosis of keratoacanthoma. The short duration of the lesion, if the patient’s history is accurate, is another factor lending support to the diagnosis of keratoacanthoma. article,’ we proposed that the inIn our previous traoral keratoacanthoma was derived from ectopic intraoral sebaceous gland tissue. The probability of the oral lesions being derived from a portion of the hair follicle, as keratoacanthomas of the skin are thought to be, seemed highly unlikely. Although initially there were no sebaceous glands seen within or in the vicinity
SUMMARY
The fourth caseof solitary intraoral keratoacanthoma has been presented. We resubmit that these lesions. when found within the oral cavity. are derived from ectopic intraoral sebaceousglands. Special thanks Zambito. Chairman contribution
and
appreciation
of the
in preparation
are
Department of this
due
10
01‘ Dentiyty,
Raymond for
hi\
manuscript.
REFERENCES I.
Fig. 3. Well-differentiatedsquamous exhibit
individual
heratinization.
cells.
(Magnification.
wmt:
of
which
x280.)
of the case presented in our last report, the patient returned 7 years later with a lesion in the sameareathat proved on pathologic examination to be sebaceous glands. This added support to our theory regarding the pathogenesisof this lesion. interestingly, thus far, the four casesthat we have accepted as being intraoral solitary keratoacanthomas have occurred in the maxilla. Two casespresentedas gingival lesions of the anterior maxilla.‘~ ’ The other two, including the one reported here. occurred on the mucosaof the hard palate.”
Svirskq, J A Freedman. P D.. and Lt~merman. H.: SoIltar! Intraoral Krr;rtoacanthorna. 0~~x1 SLKC~. 43: I I h- 12 I. I Y77 2. Ghadially, F. N Barton, B. W.. and Kcrrldge. I). F.. ‘The Etiology of Keratc~a~anthoma. Cancer 16: 603.6 I I. I YhJ i. Arar. G.. and Lu\tmann. J.: Keratoacanthoma nl the l.ower 1.1~. OR.41 SUR 37: XWXYX. lY7-1.
ir,
Dr. Paul D. Freedman Division of Oral Patholog! Department of Dentistry Catholic Medical Center of Brooklyn X8-25 lS3rd St. Jamaica. N. 1’. 11137
and
Quwn\
THE
CATHOLIC
DEPARTMENTS
MEDI~AI.
(‘ENTER
OF DENTISTRY
OF
AND
~R00tit.~x
AND
~uwrv\.
ti\jc
PA1‘HOLOG’I
The keratoacanthoma is a tumorlike proliferation clinically and microscopically, it may bear close following article discusses the keratoacanthoma intraoral keratoacanthoma.
which is rarely seen In the oral cavity. Both resemblance to squamous-cell carcinoma. The and, in addition, presents a case report of solitary
I
Microscopic
CASE
Histologic sections rcvcalcd a well-delineated raised epthelial lesion exhibiting a shallo\+ central kcratin-filled crate] (Fig. I ). T) pical stratified squamous epithelium extended up to the edge of the lesion. forming an inverted tip which undermined the normal surface (Fig. 2). Here the stratified squamous epithelium became markedly acanthotic and cxhibited numerous glassy-appearing dyskeratotic cells (Figs. 7 and 3) and scattered keratin pearls. This rpithclium extended deeply into the underlyin, cr dense fibrous connective tissue with the formation of broad-based rete ridges. The individual cells ucrc well diffcrcntiatcd and showed minimal mitotic activit) (Fig. 3). The he of the lesion displayed :I welt&lineated margin al the interf;tce with the underlying fibrous connective tiisue, I’orminp a pushing horder and showing nc, e~idcnce of infiltration.
n a previous publication, our laboratory reported what we considered to be the third acceptable case of solitary intraoral keratoacanthoma. ’ The literature was reviewed, and the possible source of histogenesis was discussed. We have since seen another case and present here the fourth report of solitary intraoral keratoacanthoma. REPORT
In December, 1976, a X-year-old woman was relerred to one of us (H. B.) with a soft-tissue growth on the anterior maxilla. Her past medical history was within normal limits. She had been edentulous for 20 years and was wearing heloriginal maxillary denture. The patient’s present illness had begun approximately 3 weeks earlier. when she noticed that her upper denture did not tit well. Clinical examination rc~
description
vealed a I .O by 7.0 cm. raised. granulomatclus-appearing mass attached to the midline of the maxilla in the arca
Diagnosis
Gross
The diagnosis was I\~ratoacanthoma. Although healing uneventful and ntr remaining disease WI\ clinically evdent. it %;I\ dcc~dctl to rc-escisc the surgic;tl :lre;l. This I-e-excision U;IS xl\ ised hecauw ;I l’e\c 01’ the pathology cow stiltants brlicvcd that Itit’ growth tnipht represent ii hilldifferentiated sqt~;~~~iol1s-c~ctI carcinoma. ~rlthough the maior114 agreed that the ICSIOI~ v+as hcnign kcratoacanthonia. C:~OII 0.7 cm., was submitted. The specimen exhibited a central core which was traversed by fissured I’olds. The tissue was sectioned in half, and both pieces were submittetl.
V.;IS
DISCUSSION “Assistant **Assistant ***Attending Warwick, ****Director,
74
Director. Oral Pathology Kesldency Trumng Attending, Division of Oral Pathology. Oral Surgeon, St. Anthony’\ Community N. Y Division
01 Oral
Patholos!
Propran~ Hwpital.
The hcratoacanthotl~~l is il tumorlike proliferatton which. clinically and microscopically, often resembles ~quatnous-cell
carcinoma.
It ordinarily
painless, rapidly appearing crateriforni I to 2 cm. in diameter. which attains
presents
as
a
lesion. usually full size in about 6
Volume Number
Solitary intraoral keratoacanthoma
47 I
Fig. 1. Low-power tion, X 1IJ.X.)
Fig.
2. Medium-power
photomicrograph
photomicrofraph
displaying
showin
the crateriform
appearance
g lip of the lesion
to 12 weeks. Spontaneous healing tends to take place over the next 4 to 6 months, with slight scar formation.’ The exposed parts of the skin, lips, cheeks, nose, and dorsum of the hands are the sites of predilection in the vast majority of cases.:{ As mentioned previously, there was controversy at the time of original diagnosis of this lesion. The differential diagnosis in this particular case was between squamous-cell carcinoma, verruwell-differentiated cous carcinoma, and keratoacanthoma. The possibility of verrucous carcinoma was discarded because of the lack of deep surface clefts filled with parakeratin. According to Lever and Shaumburg-Lever,” the most significant factor in distinguishing between well-differentiated squamous-cell carcinoma and keratoacan-
of the keratoacanthoma.
and keratin
pearl
formation.
75
(Magnifica-
(Magnification,
thoma is the over-all architecture of the lesion. We believe that the characteristic exophytic nature of this growth, its central crater, its deep-pushing border, and the undermining of the normal stratified squamous epithelium at its margin justified the diagnosis of keratoacanthoma. The short duration of the lesion, if the patient’s history is accurate, is another factor lending support to the diagnosis of keratoacanthoma. article,’ we proposed that the inIn our previous traoral keratoacanthoma was derived from ectopic intraoral sebaceous gland tissue. The probability of the oral lesions being derived from a portion of the hair follicle, as keratoacanthomas of the skin are thought to be, seemed highly unlikely. Although initially there were no sebaceous glands seen within or in the vicinity
SUMMARY
The fourth caseof solitary intraoral keratoacanthoma has been presented. We resubmit that these lesions. when found within the oral cavity. are derived from ectopic intraoral sebaceousglands. Special thanks Zambito. Chairman contribution
and
appreciation
of the
in preparation
are
Department of this
due
10
01‘ Dentiyty,
Raymond for
hi\
manuscript.
REFERENCES I.
Fig. 3. Well-differentiatedsquamous exhibit
individual
heratinization.
cells.
(Magnification.
wmt:
of
which
x280.)
of the case presented in our last report, the patient returned 7 years later with a lesion in the sameareathat proved on pathologic examination to be sebaceous glands. This added support to our theory regarding the pathogenesisof this lesion. interestingly, thus far, the four casesthat we have accepted as being intraoral solitary keratoacanthomas have occurred in the maxilla. Two casespresentedas gingival lesions of the anterior maxilla.‘~ ’ The other two, including the one reported here. occurred on the mucosaof the hard palate.”
Svirskq, J A Freedman. P D.. and Lt~merman. H.: SoIltar! Intraoral Krr;rtoacanthorna. 0~~x1 SLKC~. 43: I I h- 12 I. I Y77 2. Ghadially, F. N Barton, B. W.. and Kcrrldge. I). F.. ‘The Etiology of Keratc~a~anthoma. Cancer 16: 603.6 I I. I YhJ i. Arar. G.. and Lu\tmann. J.: Keratoacanthoma nl the l.ower 1.1~. OR.41 SUR 37: XWXYX. lY7-1.
ir,
Dr. Paul D. Freedman Division of Oral Patholog! Department of Dentistry Catholic Medical Center of Brooklyn X8-25 lS3rd St. Jamaica. N. 1’. 11137
and
Quwn\
