Atypical features in pleomorphic adenoma—a clinicopathologic study and implications for management

doi:10.1016/j.ijom.2006.02.009

International Journal of Oral and Maxillofacial Surgery

Volume 35, Issue 7, July 2006, Pages 608-612

https://doi.org/10.1016/j.ijom.2006.02.009 Get rights and content

Abstract

Pleomorphic adenoma is the most common salivary gland neoplasm and infrequently undergoes malignant transformation. Carcinoma ex pleomorphic adenoma is typically an infiltrative neoplasm with features of cellular pleomorphism, high mitotic activity, peri-neural and vascular invasion. More recently, sub-groups of pleomorphic adenoma have been described exhibiting vascular invasion and features of malignancy without evidence of extra-capsular extension. There is little information in the literature regarding how these different histological variants influence clinical presentation and outcome following primary treatment.

Following a review of 100 consecutive pleomorphic adenomas removed from the major salivary glands, 4 cases with atypical histological features were found. Three tumours exhibited features of dysplasia/carcinoma without evidence of extra-capsular invasion and a further case demonstrated benign vascular invasion. There were no clinical features suggestive of the atypical nature of these neoplasms, though fine needle aspiration cytology (FNAC) was suspicious of a malignancy in 2 cases and CT scan in 1 case. Patients underwent a superficial parotidectomy or submandibular gland excision based on the location of the lesion. All lesions were completely excised and there were no recurrences in this series.

Section snippets

Patients and methods

The case records and histology reports of 100 consecutive cases of pleomorphic adenoma of the major salivary glands treated at the Queen Alexandra Hospital, Portsmouth were reviewed and patients with atypical features identified. Four cases were noted to have atypical features and form the basis of this study. The age range was 47–77 years and included 3 female and 1 male patient. The lesion affected the parotid gland in 3 cases and the submandibular gland in 1 case. Two cases of non-invasive

Discussion

Pleomorphic adenoma is the most common neoplasm of the salivary glands and infrequently undergoes malignant transformation8, 9, 19, 21. The propensity for malignant transformation (either clinical or histological) has been documented in the literature at 1.9–23.3% and carcinoma ex pleomorphic adenoma represents approximately 12% of malignant neoplasms8, 9, 12, 13, 14, 15, 17, 20, 24. The clinical diagnosis is based on local features of malignancy in addition to regional or distant metastasis

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Pleomorphic adenoma (PA) is a salivary gland tumour characterised microscopically by architectural rather than cellular pleomorphism. The neoplasm also has finger-like projections into the pseudocapsule, which clinically has attributed to the high recurrence rate associated with the neoplasm. Vascular and neural invasion have been reported and are regarded as atypical features of the neoplasm. Review of the literature suggests that invasion of bone without malignant transformation by the neoplasm is very rare.
A 28-year-old female was diagnosed with an invasive recurrent PA of the palate, which required en-bloc resection of the left maxilla. The computed tomography scan showed a homogeneous, well-defined, multilocular lesion which extended from the anterior to the posterior of the maxilla. The histological analysis did not report any malignant transformation of the lesion. Although bone erosion is a known feature of this lesion, bone invasion is atypical. This case represents a rare occurrence of an invasive recurrent pleomorphic adenoma.
Pedunculated pleomorphic adenoma of uvula – a rare presentation
2022, Brazilian Journal of Otorhinolaryngology
Minor salivary gland neoplasms are relatively rare and account for only about 14% of the lesions of salivary glands. Pleomorphic adenomas are the most common neoplasms occurring in both major and minor salivary glands. Uvula is a relatively rare site for occurrence of pleomorphic adenoma—with palate being the commonest site. There are only 3 cases of soft palate pleomorphic adenomas reported so far. Here, we present a case of pedunculated pleomorphic adenoma of the uvula in a middle aged male, who unlike other patients reported so far, presented with a relatively rapid onset of symptoms.
An unusual presentation of pleomorphic adenoma of the soft palate in a 13-year-old boy – A case report
2016, Pediatria Polska
Pleomorphic adenoma (PA) is the commonest benign neoplasm of major and minor salivary glands. PA of the minor salivary gland in the palate is a common clinical entity. When the minor salivary glands are affected, commonly occurs at the junction of hard and soft palate. Due to its diverse clinical and morphological appearance of PA in the palate, the diagnosis is complex so histopathological examination is essential. Malignant degeneration of this lesion is a potential complication. Here we are reporting a case of PA at the soft palate which simulating to the malignant appearance which is an extreme rare presentation. The diagnosis is confirmed by histopathological examination and followed by surgical excision. PA, though a common clinical entity is still a challenging tumour for surgeon, pathologist and radiologist. The treating surgeon must be aware of its topographical diversity.
Treatment of pleomorphic adenoma of the palate: Report of two cases and review of the literature
2016, Revista Portuguesa de Estomatologia, Medicina Dentaria e Cirurgia Maxilofacial
O adenoma pleomórfico é a neoplasia mais comum das glândulas salivares. Esse tumor benigno acomete principalmente glândulas salivares maiores, com predileção pela parótida. Lesões intraorais são menos comuns e ocorrem preferencialmente no palato. O objetivo desse trabalho é relatar 2 casos clínicos de adenoma pleomórfico no palato e rever a literatura pertinente. No primeiro caso, um paciente do género masculino, de 68 anos, apresentou lesão nodular, medindo aproximadamente 2 cm, localizada no palato duro direito. No segundo caso, uma paciente do género feminino, de 31 anos, grávida, apresentou aumento de volume bem delimitado no palato duro direito, medindo aproximadamente 2,5 cm. Em ambos os casos o diagnóstico foi realizado por meio de biópsia incisional e as lesões foram tratadas com exérese cirúrgica. Os 2 pacientes foram acompanhados pelo período de 2 anos, sem sinais de recidiva. Os casos relatados contribuem para o conhecimento das características dessa importante neoplasia.
Pleomorphic adenoma is the most common salivary gland neoplasm. This benign tumor mainly affects the major salivary glands, mostly the parotid. Intraoral lesions are less common and occur preferentially in the palate. The aim of this study is to report two cases of pleomorphic adenoma in palate and review the pertinent literature. In the first case, a 68 years old male patient presented a nodular lesion, measuring approximately 2 cm, and located in the right hard palate. In the second case, a 31 years old female patient, pregnant, presented a well‐defined swelling in the right hard palate, measuring nearly 2.5 cm. In both cases, the diagnosis was made by incisional biopsy and the lesions were treated by surgical excision. The two patients were followed for a two years period with no signs of recurrence. The reported cases contribute to the knowledge about the features of this important tumor.
Benign pleomorphic adenoma of minor salivary gland showing perineural invasion: A rare entity
2015, British Journal of Oral and Maxillofacial Surgery
Citation Excerpt :
Most affect the major salivary glands and 63% occur in the parotid, usually in the superficial lobe.1 In rare cases they undergo malignant transformation, a diagnosis based on clinical features of local malignancy, regional or distant metastasis, and histological identification of invasion and cellular atypia.2 Histological findings include invasion of salivary parenchyma with extension into adjacent structures, a high mitotic rate, nuclear pleomorphism, vascular invasion, necrosis, and perineural invasion.
Perineural invasion is a rare and sporadically reported histological finding in relation to benign lesions. We present a case of a benign pleomorphic adenoma of a minor salivary gland of the cheek, exhibiting perineural involvement. There have been no previously reported cases of minor salivary gland pleomorphic adenomas exhibiting this phenomenon. This is also the first report of this rare feature in surgical literature pertaining to the head and neck region.
Radiotherapy for pleomorphic adenoma
2013, American Journal of Otolaryngology - Head and Neck Medicine and Surgery
Citation Excerpt :
These data are consistent with the University of Florida experience. Approximately 3% to 4% of pleomorphic adenomas transform to carcinoma ex pleomorphic adenoma [7,9]. In a series of 62 patients surgically resected for recurrent pleomorphic adenoma, Makeieff et al [23] reported on 10 patients (16.1%) at Le Centre Hospitalier Universitaire (Montpellier, France) who were found to have malignant transformation at the time of surgery.
The aim of this study was to update our experience in treating pleomorphic adenoma with radiotherapy (RT).
This is a retrospective analysis of 25 patients treated with RT alone (2 patients) or combined with surgery (23 patients), with follow-up ranging from 1.8 to 34.9 years (median, 10.5 years).
Local control was achieved in 13 (75%) of 16 patients with subclinical disease and 5 (56%) of 9 patients with gross disease. Overall local control was achieved in 18 (72%) of 25 patients. The 5-, 10-, and 15-year overall local control rates were 76 %, 76%, and 68%, respectively. Ten patients died of the following causes: recurrent disease, 2; malignant transformation, 2; and intercurrent disease, 6. At last follow-up, 14 patients were alive without evidence of disease, and 1 patient was alive with disease. Dental carries and transient facial nerve deficits were the most common complications. No patients developed severe complications subsequent to RT.
In patients at high risk for developing recurrent pleomorphic adenoma after surgery, RT is effective in controlling subclinical disease.

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Clinical PaperPathologyAtypical features in pleomorphic adenoma—a clinicopathologic study and implications for management

Abstract

Section snippets

Patients and methods

Discussion

Oral Pathol Oral Radiol Endod

Otolaryngol Head Neck Surg

Br J Oral Maxillofac Surg

Oral Oncology

Cell

Hum Pathol

Otolaryngol Head Neck Surg

Pathol Res Pract

Intra-vascular tumour in pleomorphic adenomas—a report of four cases

Histopathology

Atypical features in salivary gland mixed tumors: their relationship to malignant transformation

Mod Pathol

Intra-vascular tumour in intra-oral pleomorphic adenomas: a diagnostic and therapeutic dilemma

Histopathology

Genotypic alterations in benign and malignant salivary gland tumors: histogenetic and clinical implications

Am J Surg Pathol

Clinical Paper
Pathology
Atypical features in pleomorphic adenoma—a clinicopathologic study and implications for management