JCDA - Canadian Dental Association

Point of Care
warrant conventional scalpel biopsy. It is not intended for
the examination of submucosal lesions with intact surface
epithelium, such as hemangiomas or mucoceles. It can also
be used in the long-term follow-up of patients with
erythroplakic (Figs. 1 and 2) or leukoplakic lesions in
which a baseline histologic diagnosis has been obtained and
in patients with a history of oral cancer. However, a negative
result on brush biopsy does not obviate the need for
conventional tissue biopsy if the clinical presentation
warrants.
Vizilite (Zila Professional Pharmaceuticals; distributed
by Patterson Dental Supply) is a recently introduced intraoral
screening test similar to the acetowhite test, which is
used in the detection of uterine cervical dysplasias and
carcinomas. The patient rinses for 1 minute with a supplied
1% acetic acid solution to disrupt the glycoprotein barrier
on mucosal surfaces. The oral cavity is then examined with
a single-use chemiluminescent light, the wavelength of
which is absorbed by normal cells. Abnormal cells reflect
the light, presumably as a result of an increased nucleus-tocytoplasmic
ratio, and therefore appear white.
As with Orascan and Oral CDx, a positive reading with
Vizilite can be caused by minor epithelial abnormalities
associated with inflammation, irritation or ulceration and
does not necessarily mean that dysplasia or carcinoma is
present.
Question 2
This scenario emphasizes the importance of submitting
all surgical tissue to an oral and maxillofacial pathologist
for evaluation. In this case, histologic examination revealed
that what had the clinical appearance of a dentigerous cyst
was in fact an odontogenic keratocyst (OKC). On radiographic
examination OKCs range in size from small,
unilocular, pericoronal radiolucencies indistinguishable
from dentigerous cysts to large, multilocular radiolucent
lesions involving the entire mandibular ramus (Fig. 1).
OKCs (Fig. 2) are potentially aggressive cysts with a
tendency to cause significant local destruction. They are
one of the most common developmental odontogenic
cysts, second in frequency only to dentigerous cysts. They
most commonly involve the posterior body and ramus of
the mandible and are often associated with an unerupted
tooth. Clinically, OKCs tend to expand in an anteroposterior
direction within the medullary bone, with little
tendency to cause bony expansion.
The presence of multiple OKCs may be the initial
presenting sign of nevoid basal cell carcinoma syndrome
678 November 2003, Vol. 69, No. 10
It must be emphasized that these aids are not substitutes
for good clinical judgement. The most important component
in any oral cancer checkup remains a thorough visual
and digital inspection of all intraoral soft tissues, as well as
careful examination of the neck and cervical lymph nodes.
Ultimately, diagnosis of any suspicious lesion requires
histologic examination of biopsy samples. C
References
1. Johnson N, Warnakulasuriya S, Speight P, Epstein J. Diagnosing oral
cancer: can toluidine blue mouthwash help? FDI World 1998; 7(2):22–6.
2. Canadian Academy of Oral Pathology. CAOP releases toluidine blue
statement [News Item]. J Can Dent Assoc 1995; 61(9):752–3.
3. Sciubba JJ. Improving detection of precancerous and cancerous
oral lesions. Computer-assisted analyses of the oral brush biopsy. U.S.
Collaborative OralCDx Study Group. JADA 1999; 130(10):1445–57.
Further Reading
Epstein JB, Zhang L, Rosin M. Advances in the diagnosis of oral premalignant
and malignant lesions. J Can Dent Assoc 2002; 68(10):617–21.
Guo Z, Yamaguchi K, Sanchez-Cespedes M, Westra WH, Koch WM,
Sidransky D. Allelic losses in OraTest-directed biopsies of patients with
prior upper aerodigestive tract malignancy. Clin Cancer Res 2001;
7(7):1963–8.
Megevand E, Denny L, Dehaeck K, Soeters R, Bloch B. Acetic acid visualization
of the cervix: an alternative to cytologic screening. Obstet
Gynecol 1996; 88(3):383–6.
Svirsky JA, Burns JC, Carpenter WM, Cohen DM, Bhattacharyya I,
Fantasia JE, and others. Comparison of computer-assisted brush biopsy
results with follow up scalpel biopsy and histology. Gen Dent 2002;
50(6):500–3.
I recently removed an impacted mandibular third molar with an associated 10-mm pericoronal
radiolucency. Follicular tissue was submitted for biopsy. The histopathologic diagnosis was
odontogenic keratocyst. What would you recommend for follow-up?
(NBCCS), which is characterized by multiple OKCs,
multiple basal cell carcinomas, characteristic palmar and
plantar pits, and calcification of the falx cerebri. Affected
patients may also develop neoplasms such as medulloblastoma,
meningioma, ovarian fibroma and cardiac fibroma.
Histologically, OKCs are characterized by a thin, parakeratinized,
stratified squamous epithelial lining with a
hyperchromatic and palisaded basal cell layer (Figs. 3 and
4). The cyst lumen may contain desquamated keratin.
Detachment of portions of the thin cyst lining is
commonly observed at the time of surgery. The presence of
satellite cysts within the cyst wall may be responsible for the
reported 6% to 66% recurrence rate (Fig. 5). It has also
been suggested that factors inherent to the cystic epithelium
itself or influences involving regional odontogenic
epithelium may be responsible for recurrence or for the
formation of additional OKCs.
The best method of treatment remains controversial.
Current modalities include enucleation and osseous
curettage with or without resection of the overlying
Journal of the Canadian Dental Association