Metaplastic (infarcted) Warthin's tumour of the parotid gland: a possible consequence of fine needle aspiration biopsy

ArticleinHistopathology 35(5):432-8 · December 1999with42 Reads
DOI: 10.1046/j.1365-2559.1999.035005432.x · Source: PubMed
Abstract
The metaplastic (or infarcted) variant of Warthin's tumour is characterized by replacement of much of the original oncocytic epithelium by metaplastic squamous cells, along with areas of extensive necrosis, fibrosis and inflammatory change. The pathogenesis is unknown, but it is most likely to be vascular in origin. An association with a previous fine needle aspiration (FNA) has been suggested, and this is explored further. Nine metaplastic Warthin's tumours were collected from several centres: all arose in the parotid gland, and all showed the characteristic histological features. Eight had previously undergone FNA some 1-4 months before surgery; the other case had had an incisional biopsy. It is important to recognize metaplastic Warthin's tumour, because the differential diagnoses of this benign neoplasm include mucoepidermoid and squamous carcinoma, both primary and metastatic. The tumours in this study followed FNA or biopsy, and we believe this association is unlikely to be coincidental. Although many metaplastic Warthin's tumours clearly arise spontaneously, we conclude that the balance of probabilities favours the view that FNA is capable of causing metaplastic change in a Warthin's tumour, and may have done so in these cases. If so, this previously unusual subtype will become increasingly common, as FNA becomes more widely used (and its value appreciated) in the investigation of patients with a mass in the neck.
    • "The pathogenesis is unknown, but it is most likely to be vascular in origin. An association with previous fine-needle aspiration has been suggested [11]. The necrosis is commonly found together with squamous metaplasia. "
    [Show abstract] [Hide abstract] ABSTRACT: Objective: Warthin's tumors can contain markedly atypical or degenerated oncocytes; some have been mistaken for carcinoma or even metastatic carcinoma. To decrease the rate of false cytological diagnosis associated with this tumor, we tried to identify the characteristic cytologic features of Warthin's tumor oncocytes. Materials and Methods: The clinical and pathologic features of Warthin's tumor were retrospectively reviewed in 45 cases from 1998 to 2003, in which fine-needle aspirates from 13 patients were examined. Results: The male-to-female ratio was 21.5:1, the highest reported to our knowledge. Only 15 patients had a definite smoking history. Diff-Quik stained slides revealed cytologic characteristics not previously described, in which sheets of oncocytes with nuclei containing uniform, eccentric, and single pinpoint nucleoli were arranged in the same plane in all cases. Conclusion: These cells with cytologic characteristics that have not been found in other lesions with oncocytes most likely derive from the basal layer of cuboid oncocytes in Warthin's tumor. They may improve the cytological diagnostic accuracy associated with Warthin's tumor.
    Full-text · Article · Sep 2010
    • "In our cases, the differential diagnosis is mainly with malignant transformation of a pre-existing WT. The epithelial component of WT may, following various insults (trauma, FNAC), exhibit squamous and/or goblet cell metaplasia [5]. These are harmless, benign changes which, however, may cytologically very closely mimic features of mucoepidermoid carcinoma, rarely reported to arise from WT [23], and cause a real diagnostic pitfall for the cytologist. "
    [Show abstract] [Hide abstract] ABSTRACT: Tumor-to-tumor metastasis is an exceedingly rare event with only about 100 cases reported in the English written literature. We report two cases of a 65-year-old man with duplicity of colonic and lung adenocarcinomas who presented with swelling of the left parotid gland, and of a 75-year-old man who presented with swelling of the right parotid gland. Microscopical and immunohistochemical examination showed metastasis of lung carcinoma and of renal carcinoma, respectively, to Warthin tumor as the first clinical manifestation of the malignancy in the latter case. To the best of our knowledge, such a phenomenon has not been reported so far.
    Full-text · Article · Aug 2009
    • "Metaplastic WT, however, is characterized by replacement of much of the original epithelium by metaplastic squamous cells, along with regressive changes in the stroma areas (Fig. 3). Misinterpretation of metaplastic WT as a malignancy such as squamous epithelium carcinoma (PEC) or MEC presents a serious diagnostic pitfall [10,11]. The translocation t(11;19)(q21;p13) and the CRTC1eMAML2 chimeric gene have been described in MEC [12], in some WTs [7], and in some clear cell hidradenomas (CCH) [20,21]. "
    [Show abstract] [Hide abstract] ABSTRACT: The translocation t(11;19)(q21;p13) has been described in mucoepidermoid carcinoma (MEC) and rarely in Warthin tumors (WT), both tumors of the salivary gland. The translocation creates a fusion gene in which exon 1 of CRTC1 is linked to exons 2-5 of MAML2. To verify the translocation in WT, we performed nested reverse transcriptase-polymerase chain reaction using RNA from 48 WTs. This revealed the t(11;19)(q21;p13) translocation and expression of the chimeric gene in two metaplastic WT samples, but in none of the remaining ordinary 46 WTs. On review, the two positive cases were classified as tumors highly suspect for MEC. Indeed, our experience and published observations of the t(11;19)(q21;p13) translocation in WT reveal that only a small subset of WTs are positive, and that these tumors are often classified as infarcted or metaplastic WT, known to overlap considerably with MEC on purely morphological grounds. We therefore conclude that the presence of the t(11;19)(q21;p13) rearrangement favors a diagnosis of MEC.
    Full-text · Article · Feb 2008
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