|Year : 2015 | Volume
| Issue : 2 | Page : 154-156
Auricular pleomorphic adenoma: A rare presentation
Ripu Daman Arora1, Sunder Singh Dogra2, Bal Chander3, Kuldeep Thakur2
1 Department of Otorhinolaryngology and Head and Neck Surgery, All India Institute of Medical Sciences, Raipur, Chhattisgarh, India
2 Department of Otorhinolaryngology and Head and Neck Surgery, Dr. Rajendra Prasad Government Medical College, Kangra, Tanda, Himachal Pradesh, India
3 Department of Pathology and Lab Medicine, Dr. Rajendra Prasad Government Medical College, Kangra, Tanda, Himachal Pradesh, India
|Date of Web Publication||20-Apr-2015|
Dr. Ripu Daman Arora
Department of Otorhinolaryngology and Head and Neck Surgery, All India Institute of Medical Sciences, Raipur, Chhattisgarh
Source of Support: None, Conflict of Interest: None
Pleomorphic adenoma, the most common benign tumor of major salivary glands, may rarely present outside the salivary glands. However, it is extremely rare for these tumors to occur in auricle. We present a case of 40-year-old female with chief complaints of swelling in right pinna in tragal region for 3 years duration with a progressive course. Following inconclusive fine-needle aspiration cytology, excision of the mass was done under local anesthesia. Histopathology report was suggestive of pleomorphic adenoma.
Keywords: Auricle, Histopathology, Mixed salivary tumors, Pleomorphic adenoma
|How to cite this article:|
Arora RD, Dogra SS, Chander B, Thakur K. Auricular pleomorphic adenoma: A rare presentation. Indian J Otol 2015;21:154-6
| Introduction|| |
Pleomorphic adenoma is the most common benign tumor of major and minor salivary glands mostly arising from the parotid gland. The tumor generally known to be a slow growing mass and does not involve the adjacent structure. It remains clinically silent and patient usually present with cosmetic reasons. It arises either from myoepithelial cells or ductal reserve cells.  Its occurrence in skin is an unusual presentation.
The ectopic salivary tissues may undergo same pathological processes as usual salivary gland tissue. Willis  states that there are three hypotheses for salivary glands ectopia namely abnormal persistence and development of vestigial structures, dislocation of a portion of definitive organ rudiment mass and development along with the abnormal differentiation of local tissues. The ectopic salivary gland tissue may be found in other rare sites like external auditory canal, lip, lacrymal glands, hard and soft palate, middle ear, mastoid bone, tongue, tonsils and tonsillar fossa, in the neck. ,,,, Majority of external ear tumors arises from external auditory canal. The finding of a benign mixed salivary tumor in auricle is extremely rare presentation. A comprehensive review of the literature shows that only six cases of ectopic mixed salivary tumors in auricle have been found. 
We report a case of ectopic mixed salivary tumor occurring in auricle.
| Case Report|| |
A 40-year-old female patient presented with a complaint of mass in right tragal region since 3 years which was painless and progressively increasing in size. There were no other complaints. On physical examination, a subcutaneous mass of 20 mm × 10 mm in size, oval in shape arising from right tragus [Figure 1]. It was nontender, firm, immobile, and irregular in consistency. Overlying skin was normal. Rest of the ear examination, general physical examination, and laboratory investigations were not contributory to this case. Fine-needle aspiration cytology (FNAC) was done and was inconclusive. Excision biopsy was performed under local anesthesia. Vertical incision was made over tragus and mass was removed in to-to. Mass was lying in subcutaneous tissue and was separated from tragal cartilage by loose connective tissue [Figure 2]. Integrity of the overlying skin was preserved. Following excision of mass, primary closure of the defect was done. Patient was discharged from hospital and was on regular follow-up. Biopsy specimen was sent for histopathological examination. Report shows presence of the ductal epithelium along with fibromyxoid stroma and foci of cartilaginous tissue, suggestive of pleomorphic adenoma. Radiology was not needed. Postoperative healing was good. No signs of recurrence were found in 6-month follow-up period.
|Figure 1: A subcutaneous mass of 20 mm × 10 mm in size, oval in shape arising from right tragus|
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|Figure 2: Mass was lying in subcutaneous tissue and was separated from tragal cartilage by loose connective tissue|
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It was 20 mm × 10 mm oval, grey-white, smooth surfaced, well-encapsulated [Figure 3] and on cut section shows areas of bluish tissue indicating areas of gelatinous myxoid stroma without cystic degeneration.
|Figure 3: Mass was 20 mm × 10 mm oval, gray-white, smooth surfaced, well-encapsulated, and removed in to-to|
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Shows typical morphology epithelial/myoepithelial cell areas are punctuated by myxochondroid areas. The pink myxochondroid areas are a very characteristic feature of this tumor. The myxochondroid areas show the pink hyaline to fibrous stroma (right arrow) embedded in blue myxoid background [Figure 4].
|Figure 4: Section from tumor showing bland epithelial cells arranged in nests, sheets and chords along with intervening stroma and adipose tissue (H and E, ×10)|
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The myoepithelial elements may show spindle morphology and may arrange in dense fascicles mimicking myoepithelioma (hematoxylin and eosin stain).
| Discussion|| |
Pleomorphic adenoma is most common benign salivary gland tumor arising mostly from major salivary glands but can also arise from minor salivary gland tumors of normal or ectopic sites.
There are two pairs of major salivary glands namely parotid and submandibular glands and approximately 300-400 minor salivary glands found in hard palate soft palate, mucosa of cheek, peritonsiller tissue, retromolar trigone, and lateral pharyngeal wall. 
Salivary gland tissue can also rarely present in the nose, ear, neck, and mediastinum, and neoplastic changes can take place. This type of ectopic salivary gland tissue is termed as heterotopia. 
These tumors can also arise from accessory salivary gland tissue which lies anterior to parotid glands, but they are considered as normal anatomical variants.
Skin is another rare site of origin of pleomorphic adenoma where it arises from ectopic salivary gland tissue, Sebaceous glands, and sweat glands. The presence of pleomorphic adenoma in skin is known as chondroid syringoma or mixed tumor.
Pleomorphic adenoma of pinna usually presents as small painless mass which progressive increase in size. Patient seeks consultation only for cosmetic reasons as in this case. Radiological examination usually not required. FNAC aids in the diagnosis. Excision of mass can be done directly. Complete excision is the treatment of choice as incomplete removal is associated with high risk of recurrence. If the tumor is large or arising in the helix wedge resection of auricle, skin, perichondrium, and cartilage may be required. 
On microscopic examination, salivary gland tissue was present in the background of chondromyxoid area with epithelial and myoepithelial cells. This suggests that pleomorphic adenoma of auricle in this case was arising from ectopic salivary tissue not from sweat or sebaceous glands. However, histopathological features of pleomorphic adenoma arising from sebaceous glands and salivary glands are same. 
| Conclusion|| |
Pleomorphic adenoma is a rare tumor of auricle. It usually present as slow-growing painless mass with cosmetic deformity. Treatment is complete surgical excision. Its unusual location and rare occurrence add interest to this case.
| References|| |
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[Figure 1], [Figure 2], [Figure 3], [Figure 4]