J Oral Maxillofac Surg 68:179-182, 2010
Bilateral Parotid Basal Cell Adenoma: An Unusual Case Report and Review of
the Literature
Luis Junquera, DDS, MD, PhD,* Lorena Gallego, MD,†
Juan C. de Vicente, DDS, MD, PhD,‡ and Manuel F. Fresno, MD, PhD§
Basal cell adenomas (BCAs) are uncommon benign tumors of the salivary glands that were recognized as an independent entity in the second edition of the Salivary Gland Tumours Classification of the World Health Organization.1BCAs constitute approximately 1% to 2% of all salivary gland epithelial tumors.2The occurrence of bilateral basal cell adenomas is ex- tremely rare, with only 7 cases reported in the En- glish-language literature.3-9
We report an unusual case of metachronous bilat- eral parotid BCA without coexisting dermal cylin- droma and present a review of the English-language literature.
A 65-year-old woman was referred in 2003 for eval- uation of a palpable mass in the left parotid region.
Physical examination revealed a mass measuring about 3 ⫻ 2 cm, which was hard, movable, and nontender. There was no facial palsy or regional lymphadenopathy. A fine-needle aspiration cytology report was inconclusive. Magnetic resonance imaging (MRI) showed a well-defined and homogeneously well-enhanced mass occurring in the superficial lobe of the left parotid gland (Fig 1A). No calcification or
cystic component was seen within the tumor. These findings were suggestive of benign tumor of the pa- rotid gland. The gender of the patient and clinical manifestations of the lesion suggested a mixed tumor.
*Adjunct Professor, University of Oviedo, Dental School, Spain;
Staff Surgeon, Department of Oral and Maxillofacial Surgery, Cen- tral University Hospital, Oviedo, Spain.
†Attending, Department of Oral and Maxillofacial Surgery, Cen- tral University Hospital, Oviedo, Spain.
‡Chief Professor, University of Oviedo, Dental School, Spain;
Section Chief, Department of Oral and Maxillofacial Surgery, Cen- tral University Hospital, Oviedo, Spain.
§Adjunct Professor, University of Oviedo, Spain; Chief, Depart- ment of Pathology, Central University Hospital, Oviedo, Spain.
Address correspondence and reprint requests to Dr Junquera:
Oviedo University, School of Dentistry, Catedrático José Serrano Street, 33009, Oviedo, Spain; e-mail:Junquera@uniovi.es
©2010 American Association of Oral and Maxillofacial Surgeons 0278-2391/10/6801-0029$36.00/0
doi:10.1016/j.joms.2009.04.091
FIGURE 1. A, Magnetic resonance imaging (MRI) revealed left parotid mass in the superficial lobe. B, Second MRI 3 years after first surgery revealing a mass in the deep lobe of the right parotid gland.
Junquera et al. Bilateral Parotid Basal Cell Adenoma. J Oral Max- illofac Surg 2010.
JUNQUERA ET AL 179
One month later, the patient underwent left super- ficial parotidectomy, including removal of the mass, with preservation of the facial nerve and its branches.
Microscopic examination revealed varying sized and shaped aggregates of epithelial tumor cells separated by amounts of stromal tissue. The aggregates con- sisted of 2 layers of cells: dark cells with less cyto- plasm and more basophilic nuclei, and light cells, some of them with 1 or more small basophilic nucle- oli. Some cuboidal ductal cells surrounding small lu- mens were seen. Inmunoreactivity to S-100 protein was localized to the peripheral tumor cells adjacent to the connective tissue stroma. The histology was com- patible with basal cell adenoma with predominant solid pattern (Figs 2A,B) with small areas of trabecular pattern. The postoperative course was uneventful, without facial palsy.
The patient was carefully followed up; 3 years after surgery, she started complaining of swelling in the right parotid gland. Physical examination revealed an elastically hard and poorly defined right parotid mass.
Fine-needle aspiration cytology was again nondiagnos- tic. MRI revealed a right parotid mass in the caudal portion of the deep lobe (Fig 1B). On T2-weighted images, the tumor showed homogeneous moderate
intensity. With the suspected diagnosis of basal cell adenoma, right conservative parotidectomy was per- formed with facial nerve preservation. Histology re- vealed small, slightly separated nodules of basaloid cells in an insular pattern, compatible again with basal cell adenoma with solid pattern (Fig 2C). Celularity in the immunohistochemical analysis was again focally positive to S-100 (Fig 2D). Postoperatively, there were no complications and no sign of recurrence after 1 year of follow-up.
Discussion
Basal cell adenoma is a benign epithelial neoplasm with a uniform histologic appearance dominated by basaloid cells and without the myxo-chondroid tissue characteristic of mixed tumor.10 More than 80% of BCAs arise in the major salivary glands, the majority occurring in the parotid gland. An incidence of 2% to 4% of all primary salivary gland tumors is often cit- ed.10BCAs arise almost exclusively in adults.2,10The average age of patients with BCAs is 57.7 years, with a 2:1 female predominance2 except in the case of membranous basal cell adenoma, which shows a male preponderance.11 Similar to other benign salivary
FIGURE 2. A, Left intraparotid tumor nodule revealing uniform histologic appearance dominated by basaloid cells (hematoxylin-eosin). B, Histologic examination of the left tumor showing basaloid epithelial cells in large irregular-shaped sheets (hematoxylin-eosin stain⫻200). C, Histologic examination of the right tumor showing characteristics typical of basal cell adenoma: aggregates of epithelial tumor separated by stromal tissue (hematoxylin-eosin stain⫻200). D, Immunohistochemistry revealed positivity for S-100 protein in stromal cells of the right tumor (⫻400).
Junquera et al. Bilateral Parotid Basal Cell Adenoma. J Oral Maxillofac Surg 2010.
180 BILATERAL PAROTID BASAL CELL ADENOMA
gland tumors, BCAs present as a slowly enlarging, asymptomatic, freely movable mass. Their greatest dimension is usually less than 3 cm.
The bilateral occurrence of parotid tumors is rare, accounting for 1% to 3% of all parotid tumors. The most common tumor to occur bilaterally is War- thin’s tumor, reported to represent 5% to 10% of all Warthin’s tumors.12 The occurrence of bilateral BCAs of the parotid glands is unusual, and only 7 cases have been reported so far in the English literature (Table 1).3-9
There is a notable similarity between dermal eccrine tumors (eccrine spiradenoma and cylindroma) and BCAs, and a diathesis of both tumors has been reported.
It has been suggested that the histologic features of BCAs and skin tumors were similar and their synchro- nous occurrence may result from a single pleotropic gene that acts on ontogenetically similar stem cells.13 Most of the BCAs associated with dermal tumors were the membranous type, and most of the dermal tumors were cylindroma.10Four of the 7 cases reported in the English-language literature of bilateral BCAs coexisted with dermal cylindromas (Table 1).3-6
Histologically, BCAs have various variants, includ- ing solid, trabecular, tubular, and membranous vari- ants. Although the most common type is the solid variant, individual tumors commonly display a combi- nation of several growth patterns.2,10BCAs are com- posed of 2 types of cells. The first type is a small cell with scant cytoplasm and a round basophilic nucleus.
The second type presents large cells with eosino- philic cytoplasm and oval nuclei. The precise cell origin of this peculiar tumor has also been studied by immunohistochemistry. BCA subtypes appear micro- scopically basaloid and monomorphic in architectural patterns compared with pleomorphic adenoma, peri- ductal, epithelioid, and spindled (stromal-like) myo- epithelial cells contribute to the proliferation of these tumors. Positivity for S-100 protein indicates the myo- epithelial nature of these tumor cells.14
BCAs are amenable to conservative resection such as superficial parotidectomy. The recurrence rate for the solid and trabecular-tubular variants is almost nonexist- ent.10 The membranous type is the most commonly associated with recurrence (25% to 37%), and this may be a result of the multicentricity of this lesion rather than to true recurrences,2 although rare, malignant transformation is more common in the membranous type than in the other types. Male preponderance, multicentric development, absence of capsule in 50%
of cases, association with eccrine tumors, and malig- nant transformation have led some investigators to suggest that membranous type of BCA should be clas- sified separately.10
Differential diagnosis with entities of varied prog- nosis such as pleomorphic adenoma, adenoid cystic carcinoma, and basal cell adenocarcinoma makes nec- essary the consideration of this entity in the field of glandular tumors of the maxillofacial area.
References
1. Seifert G, Sobin LH: Histological Typing of Salivary Gland Tu- mors: International Histological Classification of Tumors (ed 2).
Berlin, Springer-Verlag, 1991, p 20
2. Ellis GL, Auclair PL, Gnepp DR: Surgical Pathology of the Salivary Glands (ed 1). Philadelphia, PA, W. B. Saunders, 1991, p 212
3. Reingold IM, Keasbey LE, Graham JH: Multicentric dermal-type cylindromas of the parotid glands in a patient with florid turban tumor. Cancer 40:1703, 1977
4. Herbst EW, Utz W: Multifocal dermal-type basal cell adenomas of parotid glands with co-existing dermal cylindromas. Vir- chows Arch A Pathol Anat Histopathol 403:95, 1984 5. Zarbo RJ, Ricci A, Jr, Kowalczyk PD, et al: Intranasal dermal
analogue tumor (membranous basal cell adenoma). Ultrastruc- ture and immunohistochemistry. Arch Otolaryngol 111:333, 1985
6. Schmidt KT, Ma A, Goldberg R, et al: Multiple adnexal tumors and a parotid basal cell adenoma. J Am Acad Dermatol 25:960, 1991
7. Katsuno S, Ishii K, Otsuka A, et al: Bilateral basal-cell adenomas in the parotid glands. J Laryngol Otol 114:83, 2000
Table 1. REPORTED CASES OF BILATERAL PAROTID BASAL CELL ADENOMAS IN THE ENGLISH-LANGUAGE LITERATURE
Reference Age (yrs) Gender Dermal Cylindromas Occurrence of BCAs
Reingold et al,31977 43 M Yes Metachronous
Herbst and Utz,41984 54 F Yes Metachronous
Zarbo et al,51985 58 M Yes Synchronous
Schmidt et al,61991 72 F Yes Metachronous
Katsuno et al,72000 65 F No Synchronous
Suzuki et al,82000 65 F No Synchronous
Reddy et al,92008 55 F No Synchronous
Our case 2008 65 F No Metachronous
Abbreviations: F, female; M, male.
Junquera et al. Bilateral Parotid Basal Cell Adenoma. J Oral Maxillofac Surg 2010.
JUNQUERA ET AL 181
8. Suzuki S, Okamura H, Ohtani I: Bilateral parotid gland basal cell adenomas. Case report. ORL J Oto-Rhino-Laryngology Relat Spec 62:278, 2000
9. Reddy KA, Rao AT, Krishna R, et al: A rare case of bilateral basal cell adenomas in the parotid glands. Indian J Surg 70:32, 2008
10. Ellis GL, Auclair PL: Tumors of the Salivary Glands (ed 1). Wash- ington, DC, Armed Forces Institute of Pathology, 1996, p 80 11. Christopher DM: Fletcher Diagnostic Histology of Tumors (ed 2).
Elsevier Science, 2003, p 245
12. Seifert G, Donath K: Multiple tumours of the salivary glands—
Terminology and nomenclature. Oral Oncol Eur J Cancer 32:3, 1996 13. Headington JT, Batsakis JG, Beals TF, et al: Membranous basal cell adenoma of parotid gland, dermal cylindromas, and trich- oepitheliomas. Comparative histochemistry and ultrastructure.
Cancer 39:2460, 1977
14. Zarbo RJ, Prasad AR, Regezi JA, et al: Salivary gland basal cell and canalicular adenomas: Immunohistochemical demonstra- tion of myoepithelial cell participation and morphogenetic considerations. Arch Pathol Lab Med 124:401, 2000
J Oral Maxillofac Surg 68:182-187, 2010
Management of Facial Penetrating Injury—A Case Report
Eli Tabariai, DMD,* Shabaz Sandhu, DDS,†
Gerald Alexander, DDS,‡ Ricard Townsend, MD,§
Robert Julian III, DDS, MD,储 CPT Greg Bell, DDS,¶
Allen Chien, DDS,# Beau Soares, DDS,** and Cameron Sikavi††
Penetrating injuries are described as involving body parts either partially embedded or fully transected by a foreign body.1These injuries often have devastating consequences to the patient. However, case reports
of facial penetrating injuries generally describe these injuries with less morbidity to the patient.1-19The face has protective reflexes that help divert it from incom- ing objects.9The face also has a smaller surface area than the trunk or extremities. Furthermore, the struc- ture of the face and cranium are suited to absorb shocks owing to the presence of resistant pillars, buttresses, and the presence of pneumatized cavi- ties.3,7These anatomic differences might explain why facial penetrating injuries generally result in less con- comitant injury to the patient. In addition, fatal facial penetrating injuries generally penetrate the intercra- nium and are seldom described in published reports.
The following case report presents an outline for the management of a facial penetrating injury.
Report of a Case
On November 19, 2007, at approximately 3:30 PM, a 10-year-old boy arrived at the Fresno Community Regional Medical Center emergency room with 2 large pieces of metal impaled in his neck and flank (Figs 1,2). The injury occurred after a manure spreader was inadvertently driven while the boy was playing beside the machinery. The pieces of metal were heavily soiled with dirt and manure and had T-prongs off the main stem. It was only possible to transport the patient after the metal had been trimmed down enough by the paramedic team to put the boy into the ambulance.
His initial Glasgow Coma Scale was 15, and he was answer- ing questions appropriately. His mouth opening was mea- sured at approximately 1 cm, and he was in no respiratory distress at the time. The Fresno Fire Department was en- listed to further cut and remove the metal so the patient could be positioned appropriately on a gurney (Fig 3). The primary and secondary surveys were then performed by
*Attending Surgeon, Department of Oral and Maxillofacial Sur- gery, University Medical Center–Fresno Community Medical Cen- ters, Fresno, CA.
†Resident, Department of Oral and Maxillofacial Surgery, University Medical Center–Fresno Community Medical Centers, Fresno, CA.
‡Attending Surgeon, Department of Oral and Maxillofacial Sur- gery, University Medical Center–Fresno Community Medical Cen- ters, and Private Practice, Fresno Oral/Maxillofacial Surgery Group, Fresno, CA.
§Atteding Surgeon, Department of General Surgery, UCSF Fresno Surgery Residency Program, Fresno, CA.
储Director, Department of Oral and Maxillofacial Surgery, University Medical Center–Fresno Community Medical Centers, Fresno, CA.
¶Staff, Oral and Maxillofacial Surgery, Langley Air Force Base, VA.
#Private Practice, Fresno Oral and Maxillofacial Surgery Group, Fresno, CA.
**Resident, Department of Oral and Maxillofacial Surgery, Uni- versity Medical Center–Fresno Community Medical Centers, Fresno, CA.
††Student, University of California, Los Angeles, Los Angeles, CA.
Address correspondence and reprint requests to Dr Tabariai: De- partment of Oral and Maxillofacial Surgery, University Medical Center, 445 South Cedar Avenue, Fresno, CA 93702; e-mail:oralsurgery@
hotmail.com
©2010 American Association of Oral and Maxillofacial Surgeons 0278-2391/10/6801-0030$36.00/0
doi:10.1016/j.joms.2009.09.008
182 MANAGEMENT OF FACIAL PENETRATING INJURY
