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 Table of Contents  
Year : 2020  |  Volume : 23  |  Issue : 1  |  Page : 67-71

Parotid gland neoplasms presenting as discrete infra-auricular swellings

1 State House Medical Centre; Cleft and Facial Deformity Foundation, Gwarinpa Estate, Abuja, Nigeria
2 Cleft and Facial Deformity Foundation, Gwarinpa Estate, Abuja; Department of Oral/Maxillofacial Surgery and Oral Pathology, College of Health Sciences, Obafemi Awolowo University, Ile-Ife, Nigeria
3 Department of Oral Pathology and Medicine, University of Benin, Benin City, Nigeria

Date of Submission03-Nov-2018
Date of Decision05-Feb-2019
Date of Acceptance18-May-2019
Date of Web Publication18-Mar-2020

Correspondence Address:
Dr. Bamidele Adetokunbo Famurewa
Oral/Maxillofacial Surgery and Oral Pathology, College of Health Sciences, Obafemi Awolowo University, Ile-Ife
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/smj.smj_59_18

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Background: Parotid gland neoplasms usually present as pre-auricular swellings. Sometimes, they present as solitary infra-auricular swellings which make their localization difficult as they may be confused with submandibular gland or other lateral upper neck masses. Clinicopathological reports of discrete infra-auricular parotid lesions and their surgical managements are few. Objectives: To describe the clinical features and management of discrete infra-auricular parotid masses in a series of Nigerian patients seen during a surgical outreach mission. Methodology: This is a retrospective study of all infra-auricular swellings managed by a Nigerian surgical mission over 6 years. Patients' demographics, duration of swelling, symptoms, treatment, histopathological diagnosis, postoperative complications were retrieved from patients' records. Results: A total of 124 facial tumors were seen, of which 15 (12.1%) were parotid tumors. Eight cases (53.3%) of parotid tumors presented as discrete infra-auricular masses. Age range was 13–57 years (mean = 40.9 ± 15.4 years) with male predilection. Duration of swelling was between 1 and 15 years. All lesions were treated with extracapsular dissection. One patient had postoperative facial nerve paresis, but no facial palsy and sialocele. The histopathological results were 5 (62.5%) pleomorphic adenomas, 1 (12.5%) Warthin's tumor, and 2 (25%) low-grade mucoepidermoid carcinomas. Conclusion: Discrete infra-auricular swellings may present as benign and malignant parotid gland neoplasms.

Keywords: Extracapsular dissection, infra-auricular swellings, parotid gland tumors

How to cite this article:
Bello SA, Famurewa BA, Omoregie OF. Parotid gland neoplasms presenting as discrete infra-auricular swellings. Sahel Med J 2020;23:67-71

How to cite this URL:
Bello SA, Famurewa BA, Omoregie OF. Parotid gland neoplasms presenting as discrete infra-auricular swellings. Sahel Med J [serial online] 2020 [cited 2023 Mar 31];23:67-71. Available from: https://www.smjonline.org/text.asp?2020/23/1/67/280943

  Introduction Top

Parotid gland neoplasms constitute 64%–80% of all salivary gland epithelial tumors.[1],[2] About 80% of these lesions are located in the superficial lobe of the gland and present clinically as pre-auricular swellings.[3] Sometimes, they present as solitary infra-auricular swellings which make their localization difficult as they may be confused with submandibular gland or other lateral upper neck masses.[3],[4]

Discrete infra-auricular swellings of the parotid glands almost always emanate from parotid tails.[4],[5] Parotid tail has been defined as the most inferior aspect of the parotid gland superficial lobe. It is a triangular area of superficial lobe beneath the platysma, anterolateral to the sternocleidomastoid, and posterolateral to the posterior belly of digastric muscles.[4] The parotid tail corresponds to the level of mandibular angle or an area just inferior to it.[4],[6]

Most reports on discrete infra-auricular parotid tumors are individual case reports and case series except for a paper authored by Hamilton et al., which reviewed clinico-radiological features of parotid tail lesions.[4],[7] Differential diagnoses of unilateral solitary infra-auricular swellings comprise lesions from parotid tail,[4] superior lateral neck,[3],[8] and ectopic salivary gland tissues.[9] These include pathological entities such as cervical lymphadenitis, sialadenitis, epidermoid cyst, first branchial cleft cysts, benign lymphoepithelial lesion, sarcoidosis, lymphatic malformation, venous malformation, lipoma, pleomorphic adenoma, papillary cystadenoma lymphomatosum (Warthin's tumor), mucoepidermoid carcinoma, acinic cell adenocarcinoma, non-Hodgkin's lymphoma, and cervical metastatic disease.[2],[4],[10]

Although management of parotid tumors has been generally and extensively described in head-and-neck surgical oncology literature,[11],[12],[13] specific reports on discrete infra-auricular presentation and its peculiarities are still very sparse. Partial or limited superficial parotidectomy was advocated for parotid tail neoplasms.[3],[14] Extracapsular dissection evolved as a result of general leaning toward minimally invasive surgical procedures.[14] Extracapsular dissection is a form of limited parotidectomy.[15] The technique was first described by Anderson and later by Gleave in 1975 and 1979, respectively.[16],[17] It is indicated in discrete and benign superficial parotid mass whose size is <6 cm in diameter.[18],[19] Tumor size is not a contraindication as long as the lesion is mobile in two planes, which indicates benign tumor behavior.[17],[20]

Extracapsular dissection entails careful dissection of the adjacent parotid parenchyma (of about 2–3 mm) from the tumor capsule with preservation of facial nerve.[15],[17],[18] No effort is spared in searching for facial nerve as an unseen nerve is safe from injury.[10],[18],[21] It is different from enucleation in the sense that the lesion is delivered with its capsule intact.[15],[17] Extracapsular dissection has a low recurrence rate which is comparable to superficial parotidectomy.[15],[16],[22] Reduced postoperative injury to the facial nerve and low incidence of Frey's syndrome have also been reported in patients who had extracapsular dissection.[15],[16],[23] Retromandibular depression that is typical in superficial parotidectomy is not apparent in this technique of parotid surgery.[15]

The aim of this paper was to describe the clinical features and management of discrete neoplastic parotid masses presenting as infra-auricular swellings in a series of Nigerian patients.

  Materials and Methods Top

Study population

This is a study of patients encountered during free surgical outreach programs to various local communities embarked upon by Cleft and Facial Deformity Foundation, a nongovernmental surgical foundation with focus on head- and -neck diseases that is based in Nigeria.

Study design

The study involved a retrospective review of all cases of infra-auricular swellings encountered over 6 years from January 2011 to December 2016.

Inclusion criteria

Patients with infra-auricular swellings managed during a Nigerian surgical mission over a 6 year period.

Exclusion criteria

Patients with lesions such as cervical lymphadenitis, sialadenitis, epidermoid cyst, first branchial cleft cysts, benign lymphoepithelial lesion, sarcoidosis, lipoma, pleomorphic adenoma, non-Hodgkin's lymphoma and cervical metastatic disease were excluded.

Surgical treatment

Surgical access was via modified Blair incision with limited pre-auricular extension (as necessary) was used in all patients. The cutaneous flap was raised in tissue plane superficial to parotid fascia. [17,18] With the lump in direct view, its margin was marked and a cruciform incision made over it (not into the lesion) with about 1 cm beyond its boundary. A loose areolar tissue plane was identified over and around the tumor. Thereafter, meticulous dissection was done with scissors and finger to free the lesion from surrounding areolar tissue.[17],[18],[19]

The lesion was inspected for completeness and capsule integrity to be sure there was no tumor rupture and incomplete ablation. Parotid fascia was closed with multiple interrupted 3/0 vicryl sutures. Two-layered closure of skin flap was undertaken using 3/0 vicryl and 4/0 nylon sutures for subcutaneous tissue and skin respectively.[17],[18] No suction drains were used, but pressure dressings were applied for at least 48 h postoperatively to prevent hematoma and reduce the likelihood of sialocele.[17],[18]

Data collection and analysis

Patients' demographics, duration of swelling, symptoms, treatment, histopathological diagnosis, and postoperative complications (facial nerve paresis, facial nerve palsy, and sialocele) were retrieved from patients' case notes. Collected data were analyzed using SPSS version 20 statistical software for Windows (IBM SPSS Inc., Chicago, IL, USA). Simple descriptive statistical analysis was made. Continuous variables are presented as means standard deviation. Categorical variables are presented as percentages.

Ethical consideration

The Osun State Ethics Review Committee (OSHREC/PRS/569T/147) approved the study on May 10, 2018. All patients signed or thumb-printed written informed consent forms before they were operated. Assent was taken from one patient who was below the legal age while his mother gave written consent. The patients and child's mother understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. The study complied with 2013 guideline in research, Helsinki's declaration.

  Results Top

Over 6 years, 15 outreaches were conducted in 12 communities (three locations were visited on two different occasions) across five states and Federal Capital Territory, Abuja, in Nigeria. A total of 124 cases of orofacial tumors were managed, of which 15 were parotid tumors. Eight cases of parotid tumors presented as discrete infra-auricular masses, making 6.45% of all tumors and 53.3% of parotid masses. The age range of the eight patients involved was 13–57 years, with a mean age of 40.9 ± 15.4 years. There was slight male preponderance with a male-to-female ratio of 1.67:1. Four of the lesions were found each on right and left sides of the parotid glands. There was no case of bilateral infra-auricular swelling.

Duration of swelling was 1–15 years and all patients presented with painless, slow-growing lumps typically localized within 1 cm inferior, 1.5 cm anteroinferor, and 1 cm posteroinferior to the ear lobe, respectively [Figure 1]. Facial nerve functions were intact in all cases. The swellings were not fixed to the overlying skin. There was no palpable cervical lymph node at levels I–VI in all cases.
Figure 1: Right discrete infra-auricular swelling of 3 years duration in a 28-year-old female

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Extracapsular dissection was performed for all cases with complete surgical specimens submitted for histopathological examination. All patients were operated under general anesthesia (4/8) and local anesthesia with sedation (4/8). There were no tumor spillage and ruptured capsule in all the operated cases. One of the patients had postoperative facial nerve paresis; however, there were no facial palsy and sialocele.

Six of the lesions were diagnosed as benign while two were malignant neoplasms, giving a benign-to-malignant ratio of 3:1. The spectrum of histologically diagnosed lesions involved five (62.5%) pleomorphic adenomas, one (12.5%) Warthin's tumor, and two (25%) low-grade mucoepidermoid carcinomas.

  Discussion Top

Conventionally, incisional biopsy of intrinsic parotid mass is contraindicated to prevent tumor rupture and seeding of neoplastic cells into adjacent unaffected structures.[14] In addition to clinical findings, ultrasonography and fine-needle aspiration cytology are useful diagnostic adjuncts in the management of parotid gland neoplasms.[3],[24] However, it is difficult if not impossible for most pathologists to make definitive diagnosis based on few aspirated clumps of cells because of loss of tumor architecture.[14] Furthermore, patients in this study could not afford the cost of these investigations coupled with the fact that detailed history and thorough clinical examinations can yield accurate diagnosis (of benign or malignant parotid neoplasm) in 85%–90% of cases of parotid gland swellings;[25],[26] we decided to intervene surgically and submit the whole surgical specimen to histological examination.

In the present study, the mean age was 40.9 years (range 15–52 years) which is comparable to the findings of Jude and Olu-Eddo in Benin City and Okoturo and Osasuyi in Lagos.[11],[27] The gender distribution in the present study is similar to findings of Otoh et al. and Aliyu et al. from northern Nigeria.[28],[29] This observation is in contrast to the reports of Fomete et al. with a male-to-female ratio of 1:1.18.[30]

Tumors were equally located on both sides of the parotid gland in this report. This is at variance with findings in Lagos where left parotid glands were predominantly affected.[11] Right-sided parotid gland neoplasms were frequently reported by a study in Kumasi, Ghana.[31] There is no side of predilection for parotid gland tumor in the literature.

We performed extracapsular dissection for all parotid neoplasms in this study.

All parotid neoplasms reviewed in this series justified the use of extracapsular dissection as against the conventional superficial parotidectomy.[15],[18],[19] This is in agreement with Riffat et al., who used this technique in the treatment of 46 patients with superficial benign parotid neoplasms located in the inferior pole.[10]

The absence of postoperative facial nerve palsy in this report is similar to what Riffat et al. found in Cambridge, UK.[10] Furthermore, Shehata[17] in Egypt found one case of iatrogenic transient facial nerve paresis in a cohort of 23 patients with parotid tumors strictly limited to superficial lobe which is similar to the findings from the present study. The extent of facial nerve dissection and its resultant intraoperative exposure are said to be associated with postoperative facial nerve dysfunction.[18],[32] Expectedly, there are more facial nerve morbidities in superficial parotidectomy because of facial nerve identification, dissection, and possible preservation.[14],[23] This is not the case in extracapsular dissection, where the seventh cranial nerve is not dissected unless it is in proximity to the lesion.[15],[17],[23]

We did not evaluate for Frey's syndrome in the present series. This was mainly due to itinerant nature of the surgical outreach and delayed onset of Frey's syndrome which could take up to 22 months.[33] Hancock[19] and Prichard etal.[32] reported no incidence of Frey's syndrome following extracapsular dissection technique for parotid lesion ablation. On the other hand, they found Frey's syndrome in 25% and 40% of patients who underwent superficial parotidectomy.[19],[32] Riffat etal. opined that wound closure after superficial parotidectomy allows for direct contact of raw surface of parotid deep lobe and facial nerve with subcutaneous tissue containing auriculotemporal nerve predisposing to aberrant regeneration seen in Frey's syndrome.[10] Furthermore, parotid fascia is routinely closed over residual parotid bed in extracapsular dissection which prevents direct contact (and hence neural infiltration) between parotid bed and subcutaneous tissue.[10],[17],[18],[21] Parotid fascia was properly closed in all patients in this series.

There was no incidence of sialocele in the present series. Although this complication has not been reported to be related to a particular parotid surgical technique, our observation is in consonance with Riffat et al.[10] This study is limited by short follow-up period; this is particularly important because studies have shown that to objectively assess recurrence of parotid neoplasm a minimum of 5-year post ablation is required.[34]

Non neoplastic lesion was not found in this study. This is not in agreement with the findings of Hamilton etal., who reported 15 infectious and inflammatory lesions, 16 vascular malformations, three first branchial cleft cysts, and nine Sjögren diseases.[4] This observation may be due to few cases captured in the present study.

In line with previous reports, pleomorphic adenoma was the most common tumor in our series accounting for 62.2% (5/8) and 75% (5/6) of all and benign parotid tumors, respectively.[35],[36] Although Warthin's tumor is rare among Africans,[27],[37],[38],[39] one case of Warthin's tumor was found in this study which corroborates the assertion that it has predilection for parotid tail.[2],[3],[40] There were two cases of low-grade mucoepidermoid carcinoma in our series. This is consistent with the findings of Ochicha et al. in Kano, Nigeria, and Hill in Kenya.[39],[41] Benign-to-malignant parotid tumor ratio in our study is similar to what Lawal etal. reported in Ibadan, Southwest Nigeria, but lower than the findings from Lagos where ratio 4:1 was observed.[11],[37]


The study being retrospective is dependent on availability and accuracy of data record. There is also possible selection bias.

  Conclusion Top

Based on the findings of this research, solitary and discrete infra-auricular swellings may be easily assumed a benign natured tumor in most cases. In this case series, two malignant lesions were incidentally diagnosed. Therefore, histopathological examination of complete surgical specimen is essential to determine definitive diagnosis and plan postoperative management and follow-up.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

  References Top

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