Ear Pathology Online : Salivary Gland Choristoma (Heterotopic Salivary Gland Tissue)

Choristoma (ectopic rest of normal tissue) is made up of salivary gland, glial or sebaceous gland tissue and are often seen in the middle ear biopsies. Choristomas are regarded as self-limited developmental heterotopias. There have been rare instances in which choristomas have been linked to the subsequent development of neoplasms.

Choristomas composed of recognizable salivary gland tissue may be found in a variety of locations including the middle ear. It is a distinct histopathologic entity that should be differentiated from other epithelial lesions of the middle ear.

Middle ear salivary choristomas are distinctly unusual lesions and typically manifest as unilateral conductive hearing loss; while both adult and pediatric patients have been diagnosed with middle ear choristomas, most patients have been in the first two decades of life.

As these are benign, nonprogressive lesions, treatment has been directed toward complete surgical excision whenever feasible, and biopsy for diagnosis with subsequent observation in the case of those lesions which are difficult to remove without endangering the facial nerve.

Salivary gland choristoma is a distinct histopathologic entity that should be differentiated from other epithelial lesions of the middle ear.

Salivary gland choristoma (hamartoma) of the middle ear: a case report]
Rev Laryngol Otol Rhinol (Bord). 2006;127(4):247-9.

OBJECTIVE: Middle ear salivary gland choristoma are extremly rare. We report a case, describe the clinical management and review the literature. CLINICAL CASE: A 12 year old boy presented with unilateral conductive hearing loss associated with a large inferior retraction pocket on otoscopy. CT scan demonstrated a large mass in the left middle ear cavity. The incus was absent and the stapes was partially eroded. Middle ear exploration demonstrated an 8 mm yellow/red mass in the region of the fallopian canal. This mass was comptly removed and histopathology confirmed salivary gland choristoma. CONCLUSION: These lesions result from an abnormal development of the second branchial arch. It is important to consider these lesions as part of the differential diagnosis for any unilateral hearing loss associated with a middle ear mass in children.

Salivary gland choristoma of the middle ear. Laryngoscope. 2006 Jun;116(6):1033-4.

Choristoma is a mass of tissue histologically normal for an organ or part of the body other than the site at which it is located. A rare case of ectopic salivary gland choristoma in the middle ear is described in a 14-year-old girl whose only symptom was a 55 dB conductive hearing loss. The left middle ear mass appeared whitish and was located behind the intact tympanic membrane. We first suspected it to be congenital middle ear cholesteatoma. Exploratory tympanotomy, however, revealed a salivary gland choristoma that adhered tightly to the facial nerve. Differential diagnosis and treatment of this rare condition are discussed.

Salivary gland choristoma of the middle ear in an infant: a case report.
Int J Pediatr Otorhinolaryngol. 2006 Jan;70(1):167-70. Epub 2005 Aug 1.

Salivary gland choristoma of the middle ear cavity is an extremely rare entity. Many patients with this entity usually present with conductive hearing loss. Many reports concentrate on the importance of conservative treatment of choristoma for fear of the possible injury of the facial nerve. We report another case of salivary choristoma of the middle ear in an 11-month-old girl. We performed a reconstruction surgery of the hearing mechanism, as well as tumor removal, and achieved satisfactory hearing results. If no remarkable facial nerve anomaly is detected in the preoperative evaluation, the reconstruction of the hearing mechanism with complete tumor removal might be considered.

Salivary gland choristoma of the middle ear. A review. ORL J Oto-rhinolaryngol Relat Spec. 2004;66(3):141-7.

While head and neck surgeons are accustomed to recognizing malignancies in their practices, developmental lesions are much less often encountered, and as such are not as likely to be included amongst other (more aggressive) differential diagnostic considerations. One such developmental lesion is the choristoma, defined as an architecturally normal arrangement of mature tissues found in a location not normally host to such tissues. Choristomas composed of recognizable salivary gland tissue may be found in a variety of locations including the middle ear. Middle ear salivary choristomas are distinctly unusual lesions and typically manifest as unilateral conductive hearing loss; while both adult and pediatric patients have been diagnosed with middle ear choristomas, most patients have been in the first two decades of life. As these are benign, nonprogressive lesions, treatment has been directed toward complete surgical excision whenever feasible, and biopsy for diagnosis with subsequent observation in the case of those lesions which are difficult to remove without endangering the facial nerve. There have been rare instances in which choristomas have been linked to the subsequent development of neoplasms, but in the main choristomas are regarded as self-limited developmental heterotopias.

Choristoma of the middle ear: a component of a new syndrome?Otol Neurotol. 2001 May;22(3):363-8.

CASE REPORT: Salivary choristoma of the middle ear is a rare entity. The authors report the 26th known case, which is unique in several respects: the patient had abnormalities of the first and second branchial arches, as well as the otic capsule and facial nerve in ways not yet reported. Our patient presented with bilateral preauricular pits, conchal bands, an ipsilateral facial palsy, and bilateral Mondini-type deformities. A review of the literature revealed salivary choristomas of the middle ear to be frequently associated with branchial arch abnormalities, most commonly the second, as well as abnormalities of the facial nerve. REVIEW OF THE LITERATURE: All 25 cases were reviewed and the results reported with respect to clinical presentation, associated abnormalities, operative findings, and hearing results. It has been proposed that choristoma of the middle ear may represent a component of a syndrome along with unilateral hearing loss, abnormalities of the incus and/or stapes, and anomalies of the facial nerve. CONCLUSION: Eighty-six percent of the reported patients with choristoma have three or four of the four criteria listed to designate middle ear salivary choristoma as part of a syndrome. In the remaining four patients, all of the structures were not assessed.

Salivary gland choristoma of the middle ear: a case report. Am J Oto-laryngol. 2000 Mar-Apr;21(2):127-30.

A choristoma is a nonneoplastic proliferation of histologically normal tissue that forms at an abnormal site. It is extremely uncommon in the middle ear space. It appears to be a developmental abnormality and may be associated with abnormalities of adjacent structures. It usually occurs with unilateral conductive hearing loss and requires a differential diagnosis from other mass lesions in the middle ear cavity. This article discusses a case of salivary gland choristoma of the middle ear that we believe to be the 24th case reported on this subject.

Salivary gland choristoma in the middle ear: a case report. Am J Oto-laryngol. 1999 Jul-Aug;20(4):232-5.

Salivary gland choristoma (ectopic or heterotopic salivary gland tissue) is a rare condition that occurs in various locations within the head and neck regions. We present a 13-year-old boy with a salivary gland choristoma in the middle ear associated with congenital alopecia around the auricle in addition to facial nerve and ossicular chain abnormalities. Because the lesions commonly involve the facial nerve, intraoperative facial nerve monitoring is helpful in allowing safe biopsy without facial nerve damage.

Salivary gland choristoma of the middle ear: report of a case and review of the literature.Ear Nose Throat J. 1996 Jul;75(7):422-4.

Salivary gland choristoma (heterotopic salivary gland tissue) is a rare condition that occurs at various locations within the head and neck. We present a 10-year-old boy with a salivary gland choristoma of the middle ear and compare findings with the 15 similar cases published in the English and German languages. Patients typically have a long-standing conductive hearing loss and visible middle ear mass. Operative findings include a lobulated middle ear mass of histologically normal salivary gland tissue attached posteriorly in the region of the oval window, together with absent or malformed ossicles. Frequently the mass is intimately associated with the facial nerve. The constancy of these findings has led to the proposal of an abnormal developmental syndrome. This syndrome will be described and possible explanations for its cause will be discussed.

Choristoma of the middle ear.Eur Arch Otorhinolaryngol. 1996;253(3):182-4.

Salivary gland choristoma in the middle ear. Ugeskr Laeger. 1994 Aug1;156 (31):4474-5.

A choristoma is a non-neoplastic proliferation of histologically normal tissue occurring at an abnormal site. The first known Danish case of a salivary gland choristoma in the middle ear is presented. This is a very rare condition of which only 20 cases have been reported. A 16-year-old male was referred to the ENT clinic with a 60-70 dB mixed hearing loss on the right ear. Exploratory tympanotomy showed a lobulated mass attached to the horizontal portion of the facial nerve, which had an abnormal course lateral to the stapes. The incus and stapes were abnormal with no continuity. Biopsy showed salivary gland choristoma. Complete excision was not attempted. Postoperatively the conductive hearing loss was for some reason reduced by 20 dB. The facial nerve function was normal.

Salivary gland choristoma of the middle ear.J Laryngol Otol. 1992 Jul; 106 (7):630-2.

A salivary gland choristoma is an extremely uncommon tumour in the middle ear space. It appears to be a developmental abnormality and may be associated with abnormalities of adjacent structures. It usually presents with unilateral conductive deafness which may be long-standing and the tumour often pursues a benign, slow growing course. It is usually possible to excise it, but problems may arise as there may be variable associated anatomical abnormalities of the middle ear. We present the nineteenth recorded case, review the literature and discuss the management of this condition.

Salivary gland choristoma of the middle ear. Arch Pathol Lab Med. 1982 Jan;106(1):39-40.

Salivary gland choristoma (ectopic salivary gland tissue) is an unusual condition that occurs in various locations within the middle ear. It is a distinct histopathologic entity that should be differentiated from other epithelial lesions of the middle ear. Since the lesion commonly involves the facial nerve, its recognition is particularly critical to avoid unnecessary severing of the nerve.