First published online May 11, 2009
British Journal of Radiology (2009) 82, 916-919
© 2009 British Institute of Radiology
doi: 10.1259/bjr/30175196
Warthin's tumour: a retrospective case series
T R TAYLOR, MBChB, MRCP, FRCR
1
N J A COZENS, MBChB, DMRD, FRCR
2 and
I ROBINSON, MB, FRCPI, FRCPath
3
1 Department of Neuroradiology, Queens Medical Centre, Nottingham, UK, Departments of 2 Radiology and 3 Pathology, Derbyshire Royal Infirmary, Derby, UK
Correspondence: T R Taylor, Department of Neuroradiology, Queens Medical Centre, Nottingham, UK. E-mail: timt{at}nhs.net
 |
Abstract
|
|---|
Warthin's tumour (benign cystadenolymphoma) is the second most common salivary gland tumour after pleomorphic salivary adenoma, and it is commonly encountered in routine head and neck ultrasonography. Tissue diagnosis can be achieved by fine-needle aspiration. Infarction and inflammatory response following fine-needle aspiration is previously described in excision specimens. We describe 7 cases of radiologically infarcting Warthin's tumours in situ in a retrospective analysis of 76 patients, and demonstrate an approximate incidence of at least 9% of infarction following fine-needle aspiration in lesions left in situ. We recommend the possibility of infarction and associated clinical symptoms being incorporated into pre-fine-needle aspiration patient counselling.
|
Introduction
|
|---|
Warthin's tumour (benign cystadenolymphoma) is the second most common salivary gland tumour after pleomorphic salivary adenoma. It is thought to be more common in males and smokers [1], and is bilateral in approximately 10% at presentation [2], with multifocal lesions presenting occasionally.
These tumours are commonly encountered in routine head and neck ultrasonography, and tissue diagnosis can be achieved by fine-needle aspiration (FNA). Our current practice is that these lesions can remain in situ following FNA confirmation, particularly if the patient has significant medical comorbidity, which would increase the risks of a parotidectomy.
There are several case series in the current literature describing histological features of infarction and acute inflammatory response following FNA [3] and subsequent excision [4, 5]; this paper demonstrates the radiological findings of infarcting Warthin's tumour in several cases. We also suggest an approximate frequency of clinical infarction following FNA in lesions left in situ, in order to increase awareness of this relatively uncommon phenomenon amongst radiologists and to allow for appropriate pre-FNA patient counselling.
|
Methods and materials
|
|---|
Since 1996, at our centre 51.2% of parotid masses with an ultrasound-guided FNA specimen demonstrating Warthin's tumour have not been resected or had any other treatment. A retrospective review of these cases was performed. Records were reviewed for a period of 12 years from 1996 to 2008. Tissue diagnosis of Warthin's tumour, without subsequent parotid resection or other treatment, was available for 79 cases. Correlative radiology records were not available for 3 cases, giving a final cohort of 76 cases. Demographics of this cohort were 48 men, 28 women and a mean age at examination of 69.5 years (range 44.0–91.8 years).
Warthin's tumour was suggested as a "probable" or "likely" diagnosis on ultrasound findings in 57 of 76 reports, prior to formal histology being available.
|
Results
|
|---|
20 cases went on to have repeat imaging, which could be for any reason. 11 lesions demonstrated static appearances on ultrasound; 3 lesions demonstrated a slight increase in size and 1 lesion demonstrated multifocal change, although the index lesion was unchanged in size. Six lesions demonstrated marked reduction in size and/or other features, suggesting possible infarct, and in one further case follow-up imaging was not performed at our centre but imaging and clinical findings elsewhere confirmed infarct of Warthin's tumour.
Case studies
Patient 1, an 86-year-old man, presented with a painful left parotid mass (Figure 1
). Ultrasound features were consistent with a Warthin's tumour and guided FNA was performed, which confirmed Warthin's tumour cytologically. Ultrasound at 3 and 6 months following FNA demonstrated progressive reduction in size of the parotid tumour, consistent with infarction.
View larger version (42K):
[in this window]
[in a new window]
|
Figure 1. (a) A 3.2 cm left parotid lesion. (b) A Warthin's tumour was confirmed by histology following fine-needle aspiration performed with a 21-G needle. (c) Repeat ultrasound 3 months later demonstrates marked involution of the parotid lesion.
|
|
Patient 2, a 71-year-old man, presented with a right parotid mass. Ultrasound demonstrated the lesion and guided the FNA but the lesion's features were otherwise non-specific. 3 months following FNA, which confirmed Warthin's tumour, subsequent ultrasound demonstrated a dramatic reduction in size of the mass. A further ultrasound 9 years later showed only a tiny right residual mass, but also demonstrated a new Warthin's tumour in the contralateral parotid.
Patient 3, a 68-year-old woman, presented with a right parotid mass, which was felt to represent a rather vascular atypical pleomorphic adenoma on initial ultrasound. Guided FNA was painful and confirmed Warthin's tumour. Ultrasound at 3 months demonstrated no significant change in size, but markedly reduced vascularity consistent with infarction. A further ultrasound 3 years later (after no other intervention) confirmed complete involution of the right parotid lesion, and also demonstrated a new Warthin's tumour in the contralateral parotid.
Patient 4, a 52-year-old woman, presented with right-sided neck swelling. Ultrasound features were described as "multicystic disease" of the head and neck, and guided FNA of right parotid confirmed a Warthin's tumour. Further ultrasound 2 months later demonstrated marked reduction in the size of the right parotid lesion.
Patient 5, a 60-year-old woman, presented with a left parotid mass. Ultrasound features were consistent with a Warthin's tumour, which was confirmed by FNA (Figure 2). A subsequent MRI for facial pain 1 month later demonstrated proteinaceous fluid within an enlarged left parotid mass, consistent with acute intraglandular inflammation. Further ultrasound 1 month later confirmed marked reduction in the size of the left parotid mass, most likely representing infarction.
View larger version (20K):
[in this window]
[in a new window]
|
Figure 2. (a) Fine-needle aspiration of a 3.4 cm left parotid lesion confirmed Warthin's tumour on histology. (b) Axial T1 fat saturation MRI 1 month later shows cystic enlargement of the lesion with a surrounding parenchymal response, in keeping with inflammation. (c) Ultrasound 1 month later demonstrates marked involution of the lesion, now measuring 1 cm.
|
|
Patient 6, a 64-year-old man, presented with a palpable right parotid mass. Ultrasound features were consistent with a Warthin's tumour, which was confirmed by FNA. Several days following FNA, the patient developed progressive facial pain and swelling. Further imaging at another centre demonstrated perilesional change and slight enlargement, highly suggestive of acute inflammation, which was treated symptomatically. Subsequent follow-up confirmed complete clinical resolution of the parotid mass.
Patient 7, a 61-year-old man, presented with a right parotid mass with ultrasound features of a Warthin's tumour, which was confirmed by FNA (Figure 3). Further ultrasound 7 months later demonstrated almost complete involution of the right parotid lesion with only a very small remnant.
View larger version (46K):
[in this window]
[in a new window]
|
Figure 3. (a) A 1.6 cm right parotid lesion. (b) A Warthin's tumour was confirmed by histology following fine-needle aspiration performed with a 21-G needle. (c) Repeat examination 7 months later demonstrates almost complete involution of the lesion, now measuring 0.4 cm.
|
|
|
Discussion
|
|---|
The mean time to follow-up imaging in the general cohort was 1.4 years: the mean time to follow-up imaging in the "infarct" subgroup was 0.4 years. The most likely explanation for this difference is that rapid clinical changes manifest in an infarcting Warthin's tumour provoked early repeat ultrasound, rather than defaulting to "routine" follow-up from the clinic.
The percentage of Warthin's tumours showing radiological infarction following FNA in our case cohort of unresected Warthin's tumours is at least 9%. It is likely that the true percentage is higher, as only a relatively small number of the original cohort have undergone repeat imaging and several patients may have silently infarcted their tumour without clinical symptoms triggering further imaging.
In our centre, the great majority of patients referred with a suspected parotid mass undergo ultrasound and ultrasound-guided FNA as the primary imaging investigation, with immediate review of the sample by an experienced pathologist. The benefits of this approach, over primary investigation with MRI, include the ability to obtain imaging and cytological diagnosis for a single patient event and to obtain confirmation of adequate material at the time of FNA, so keeping recall to a minimum and enabling appropriate post-procedure counselling as required. However, it is probably advisable to counsel the patient regarding the possibility of post-FNA infarction or inflammation prior to a parotid FNA being performed; three out of seven of our cases did not have "classical" features of a Warthin's tumour at ultrasound. In retrospectively reviewing the original ultrasound images, no significant differences could be determined between those cases that subsequently went on to infarction and those that remained static.
We have not found any specific ultrasound features to suggest infarction other than size reduction in the appropriate clinical context, including initial cytological confirmation of Warthin's tumour. Lesion vascularity on initial power Doppler examination is often relatively sparse, but Warthin's tumours that did contain areas of vascularity on initial examination showed a reduction in this vascularity as the tumour size reduced.
Surgical excision of a benign lesion that has disappeared or become much smaller clinically would be difficult to justify, particularly as none of the patients in our series wanted to undergo any surgical intervention after significant reduction in size of their Warthin's tumour. Our inclusion criteria also specifically excluded those patients who had gone on to surgical excision. Formal histological confirmation of infarction in these seven cases has therefore not been obtained.
Our assumption that the demonstrated changes constitute infarction is an extrapolation from the clinically observed behaviour, previous literature and previous local patients who did not have any post-FNA imaging (and therefore could not be included in this series) but exhibited a similar reduction in lesion size post FNA. Histological examination of these excised lesions confirmed an infarcted Warthin's tumour.
Work by previous authors [6] has stressed the importance of an awareness of previous FNA procedures in order to avoid potential misdiagnosis when reviewing resected parotid specimens. We suggest that awareness of previous FNA may also be helpful to the radiologist when reviewing cases of acute parotid pain or swelling, in order that an appropriate differential may be suggested to the clinician (who may be unaware of previous FNA in the acute setting).
Further detailed evaluation of the likely time course of post-FNA infarction cannot be accurately assessed from this retrospective case series, for several reasons. We do not routinely rescan patients post FNA, particularly not sequentially, as would be required to assess the time course. Several of the patients whose Warthin's tumours reduced in size could not recall any symptoms of either pain or increased swelling post FNA on subsequent questioning; conversely, two patients did recall significant pain and swelling, the onset of which was within a few days post FNA. This relatively small case series of this unusual observation would not accurately predict the time course; whilst clearly variable, the acute swelling (if noticed by the patient) occurred within days, with regression of the size of the lesion noticed or observed at repeat imaging several weeks or months post FNA.
|
Conclusions
|
|---|
This retrospective series demonstrates that spontaneous infarction of a Warthin's tumour following FNA may be more common than has previously been reported, at around 9% in unresected tumours. We recommend that if a Warthin's tumour is suspected on sonographic findings, the patient should be informed prior to FNA that the procedure may cause spontaneous infarction and involution of the tumour, and that in some cases this may lead to pain and swelling days to weeks after the original aspiration. It can also contribute to the patient's non-operative management with regression of the parotid mass.
Received for publication November 25, 2008.
Revision received January 6, 2009.
Accepted for publication January 19, 2009.
|
References
|
|---|
- Kotwall CA. Smoking as an etiologic factor in the development of Warthin tumor of the parotid gland. Am J Surg 1992;164:646–7.[CrossRef][Medline]
- Teymoortash A, Krasnewicz Y, Werner JA. Clinical features of cystadenolymphoma (Warthin tumor) of the parotid gland: a retrospective comparative study of 96 cases. Oral Oncology 2006;42:569–73.[CrossRef][Medline]
- Bahar G, Dudkiewicz M, Feinmesser R. Acute parotitis as a complication of fine-needle aspiration in Warthin tumour. A unique finding of a 3-year experience with parotid tumor aspiration. Otolaryngol Head Neck Surg 2006;134:646–9.[CrossRef][Medline]
- Di Palma S, Simpson RHW, Skalova A, Michal M. Metaplastic (infarcted) Warthin tumour of the parotid gland: a possible consequence of fine needle aspiration biopsy. Histopathology 1999;35:432–8.[CrossRef][Medline]
- Starek I, Skalova A, Tichy T. Histopathologic changes in parotid gland parenchyma after FNA biopsy of warthin tumour. A case report. Pathol Res Pract 2002;198:829–32.[CrossRef][Medline]
- Li S, Baloch ZW, Tomaszewski JE, LiVolsi VA. Worrisome histologic alterations following fine-needle aspiration of benign parotid lesions. Arch Pathol Lab Med 2000;124:87–91.[Medline]
Top
Abstract
Introduction
