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Open Access Highly Accessed Case report

Poorly differentiated carcinoma arising from adenolymphoma of the parotid gland

Stefano Ferrero1, Laura Cattaneo1, Andrea Peri2, Paola Braidotti1, Ugo Cioffi3, Gabriele Scaramellini2, Michele M Ciulla4, Matilde De Simone3, Carmelo Arizzi1 and Lorenzo Pignataro2*

Author Affiliations

1 Pathology Unit, Azienda Ospedaliera S. Paolo and Ospedale Maggiore di Milano, University of Milan, Milan, Italy

2 Department of Otorhinolaryngology, Ospedale Maggiore di Milano, I.R.C.C.S., Milan, Italy

3 Department of Surgery, Ospedale Maggiore di Milano, I.R.C.C.S, University of Milan, Milan, Italy

4 Institute of General Clinical Medicine and Medical Therapy, Centre of Clinical Physiology and Hypertension, Ospedale Maggiore di Milano, I.R.C.C.S, University of Milan, Milan, Italy

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BMC Surgery 2003, 3:1  doi:10.1186/1471-2482-3-1


The electronic version of this article is the complete one and can be found online at: http://www.biomedcentral.com/1471-2482/3/1


Received:22 October 2002
Accepted:17 January 2003
Published:17 January 2003

© 2003 Ferrero et al; licensee BioMed Central Ltd. This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original URL.

Abstract

Background

There is only one previous case report of a poorly differentiated carcinoma arising from an adenolymphoma of the parotid gland (Warthin's tumour). The absence of clinical symptoms, and the aspecificity of the radiological pattern make the diagnosis very difficult.

Case presentation

We here report the case of a 73-year-old man with Warthin's tumour who was brought to our attention because of a swelling in the parotid region.

Conclusions

In this case with an atypical clinical presentation, the intra-operative examination of a frozen section of the parotid mass allowed us to diagnose the malignant tumour correctly and consequently undertake its radical excision.

Keywords:
Warthin's tumour; malignant adenolymphoma; parotid gland; salivary gland carcinoma

Background

Adenolymphoma (also called Warthin's tumour: WT) is a benign neoplasm of the salivary glands that almost exclusively occurs in the parotid gland, more often at the inferior pole, and usually affects white men aged 55 years. It has a classical composite histological appearance, with an epithelial component and a lymphoid stroma. The malignant transformation of WT is a very rare event. The lymphoid component may evolve into malignant lymphoma [1], whereas the epithelial component may develop into mucoepidermoid carcinoma [2], adenocarcinoma [3] or squamous cell carcinoma [4-7]. To the best of our knowledge, only Onder [8] has previously reported a case of poorly differentiated carcinoma of the parotid gland arising from WT.

Case presentation

A 73-year-old man was brought to our attention in January 2001 because of a swelling in the right parotid region, which had appeared three years before but had always been neglected by the patient because of its asymptomatic nature. It had apparently grown more rapidly over the previous two months, and a physical examination revealed the presence of a voluminous mass with a regular border that was mobile on the superficial and deep planes, and did not hurt upon palpation. There were no palpable cervical lymph nodes.

Three weeks before, the patient had undergone an ultrasound (US) examination of the neck and salivary glands, and a fine-needle aspiration biopsy revealed a mass on the superficial lobe of the parotid. The biopsy specimen suggested Warthin's tumour, but was negative for malignant cells. The computed tomography (CT) scan made using intravenous contrast medium confirmed the presence of a 3.4 × 2.5 cm mass on the right parotid gland. No pathological lymph nodes were identified (Fig. 1).

thumbnailFigure 1. An axial computed tomography scan with contrast medium showing a 3.4 × 2.5 cm mass on the right parotid gland (arrows).

The patient underwent a right superficial parotidectomy and, as an analysis of a frozen section showed the presence of poorly differentiated carcinoma cells, the surgeon extended the exeresis of the gland to the lower pole, preserving the facial nerve which was unaffected by the neoplasm. There were no right facial nerve deficits after the operation. The surgical specimen (3.5 × 2.5 × 1 cm) had a well-circumscribed, spherical, soft grey nodule with a few small cysts (a typical WT); the inner portion consisted of a harder yellow mass measuring 1.7 cm that proved to be a poorly differentiated carcinoma (Fig. 2).

thumbnailFigure 2. Left panel (enlargement 10×): undifferentiated carcinoma with poorly squamous differentiation (bottom right) very near to a typical Warthin's tumour (upper left). The arrows indicate the transition zone from a benign to malignant neoplasm. Right panel (enlargement 40×): detail of the malignant area. Hematoxylin and eosin stains.

The grey nodule was histologically characterised by a prominent lymphoid matrix with germinal centres. The surface of this lymphoid tissue was covered by papillations of large epithelial cells forming cystic spaces with oncocytic features. The cells were arranged in two layers: the inner layer consisted of cuboid and polygonal cells containing nuclei with prominent nucleoli; the outer layer consisted of tall and sometime ciliated columnar cells, with centrally located pyknotic nuclei and a peripheral fibrous capsule. The oncocytic epithelial component inside the typical WT showed a hyperplastic-dysplastic change confluent with solid undifferentiated neoplasm (Fig 3a,3b); the malignant epithelial component, which was immunoreactive to an anti-cytokeratin pool (AE1-AE3; Dako), consisted of nests or single cells with a surrounding desmoplastic stroma sometimes infiltrated by small lymphocytes and plasma cells (Fig. 3b,3c). There were two types of intermitted cells loosing the papillary formation. The first were large cells with hyperchromatic nuclei, prominent nucleoli and thick chromatin along the nuclear membrane, abundant cytoplasm and well-demarcated cell membranes; no intercellular bridges or keratin production could be identified in these areas. The second were smaller eosinophil cells containing numerous eosinophilic granules, with oval nuclei, clumped chromatin and a centrally located eosinophilic nucleolus. The presence of mucin was excluded by PAS and PAS diastase staining of the paraffin blocks. Peripherically, small clusters of tumour cells penetrated the fibrous capsule and infiltrated the surrounding salivary gland.

thumbnailFigure 3. Upper panels, hematoxylin and eosin staining. Panel (a) shows a low resolution (5 ×) image of the oncocytic transition from typical papillae (asterisk) and a hyperplastic-dysplastic state (cross) to malignant transformation (circle). Panel (b) shows a 10× enlargement of the undifferentiated carcinoma with a few atypical mitoses (arrows). Lower panels, immunohistochemistry anti-cytokeratin staining: panel (c) shows a 10× enlargement of the undifferentiated carcinoma immunoreactive to cytokeratin, and panel (d) a detail (40×) of a very atypical cell with cytoplasmic anti-cytokeratin immunoreactivity.

The postoperative course was uneventful. The patient underwent postoperative radiotherapy because of the results of the histological examination. Now, 20 months after surgery, he is well and and has not experienced any recurrence.

Conclusions

Our patient with a poorly differentiated carcinoma arising in WT was asymptomatic and showed no signs, such as the clinical lymph node metastases or facial nerve palsies described by some authors [4,5]. The cytological results were not reliable as the fine-needle biopsy specimen of the parotid mass suggested Warthin's tumour but was negative for malignant cells. As the epithelial tumour component involved more than 50% of the neoplastic area, the case can be classified as subtype 1 (typical cystoadenolymphoma) according to Seifert et al. [9].

Our findings confirm the possibility of a malignant transformation of the epithelial component of a WT. It is worth underlining the diagnostic difficulty caused by the absence of clinical symptoms and the non-specific nature of the radiological signs; furthermore, false negative cytology for malignant cells is not a rare occurrence. In order to ensure a correct therapeutic approach, we recommend the use of intra-operative frozen section analysis in order to exclude malignant transformation when dealing with an atypical clinical presentation. Finally, from the histological point of view, we suggest considering a malignant transformation only when the bulk of the carcinoma is inside the WT and the oncocytic epithelial component simultaneously shows a transition zone from a hyperplastic-dysplastic state to malignancy.

List of abbreviations

Warthin's tumour = WT

Ultrasound = US

Computed tomography = CT

Competing interests

None declared.

Authors' contributions

LP, AP and GS enrolled the patient for clinical and surgical aspects. SF, LC, CA and PB did the histopathological examination and made the diagnosis. UC and MDS participated in the diagnosis and drafting the case report. MMC contributed to setting up the images and editing the case report.

Acknowledgements

Written consent was obtained from the patient or their relative for publication of the patient's details.

References

  1. Banik S, Howell JS, Wright DH: Non Hodgkin's lymphoma arising in adenolymphoma – A report of two cases.

    J Pathol 1985, 146:167-177. PubMed Abstract OpenURL

  2. Williamson JD, Simmons BH, El-Naggar A, Medeiros LJ: Mucoepidermoid carcinoma involving Warthin tumor – A report of five cases and review of the literature.

    Am J Clin Pathol 2000, 114:564-570. PubMed Abstract OpenURL

  3. Brown L, Aparicio SR: Malignant Warthin's tumor: an ultrastructural study.

    J Clin Pathol 1984, 37:170-175. PubMed Abstract OpenURL

  4. McClatchey KD, Appelblat NH, Langin JL: Carcinoma in papillary cystadenoma lymphomatosum (Warthin's tumour).

    Laryngoscope 1982, 92:98-99. PubMed Abstract OpenURL

  5. Morrison GAJ, Shaw HJ: Squamous carcinoma arising within a Warthin's tumour of the parotid gland.

    J Laryngol Otol 1988, 102:1189-1191. PubMed Abstract OpenURL

  6. Gunduz M, Yamanaka N, Hotomi M, Kuki K, Yokoyama M, Nakamine H: Squamous cell carcinoma arising in Warthin's tumor.

    Auris Nasus Larynx 1999, 26:355-360. PubMed Abstract | Publisher Full Text OpenURL

  7. Siefert G: Carcinoma in pre-existing Wartin tumors (cystadenolymphoma) of the parotid gland. Classification, pathogenesis and differential diagnosis.

    Pathologe 1997, 18(5):359-367. PubMed Abstract | Publisher Full Text OpenURL

  8. Onder T, Tiwari RM, Van der Waal I, Snow GB: Malignant adenolymphoma of the parotid gland: report of carcinomatous transformation.

    J Laryngol Otol 1990, 104:656-661. PubMed Abstract OpenURL

  9. Seifert G, Bull HG, Donath K: Histologic subclassification of the cystadenolymphoma of the parotid gland. Analysis of 275 cases.

    Virchows Arch A Pathol Anat Histol 1980, 388(1):13-38. PubMed Abstract OpenURL

Pre-publication history

The pre-publication history for this paper can be accessed here:

http://www.biomedcentral.com/1471-2482/3/1/prepub