Kavernöses Hämangiom der Glandula parotis im Erwachsenenalter

[Epidemiology, diagnosis, and treatment of giant pleomorphic adenomas of the parotid gland]

Pleomorphic adenomas of the parotid gland can be slowly growing over the course of many years and may reach an enormous and disfiguring size associated with significant morbidity of the patients. To our knowledge, over the last 80 years 20 cases of giant pleomorphic adenomas (weight 1.2-26.5 kg) have been reported. These tumors occurred predominantly in women (90%). The mean period from initial clinical manifestation until definitive surgical treatment was 20.7 years. The mean age of the patients at the time of surgery was 58.9 years. Malignant transformation occurred in 15.8% of cases. It is likely that the reasons for delayed treatment are the patient's fear of surgery on the one hand, and insufficient medical advise on the other. We report on a 77 year old female who had a 40-year history of a growing parotid tumor that weighed 3.9 kg after resection. The implications of this case for diagnosis and treatment of giant pleomorphic adenomas, and a review of the world literature on these unusual parotid tumors, are presented.

Kann die präoperative Feinnadelpunktion bei Parotistumoren die definitive histologische Diagnose erschweren?

INTRODUCTION

Fine-needle aspiration cytology (FNAC) is a minimally invasive procedure that offers high specifity and acceptable sensitivity in the preoperative diagnosis of parotid tumors. FNAC provides information that can be particularly valuable in surgical planning and patient education. In some cases, it may even help prevent unnecessary surgery. After an FNA procedure, on rare occasions, morphological changes in the tumor may be observed and can make a definitive histological examination difficult or even impossible.

METHODS

Histopathological changes in parotid tumors after preoperative FNAC are described on the basis of a case report and a survey of the literature.

RESULTS

In rare cases, puncture-induced histopathological changes, such as hyalinization of the subepithelial stroma, necrosis and squamous metaplasia, so extensive that a definitive histological diagnosis is difficult, are observed. In the present case report, fine-needle aspiration of a 3 x 2 cm tumor, which had been classified as malignant on the basis of cytological findings, resulted in complete necrosis and made a definitive histological diagnosis impossible. Similar cases have been described by other authors in recent years.

DISCUSSION

In rare cases, histological changes in the tumor tissue can occur after an FNA procedure, making a definitive histological examination difficult or even impossible. When a preoperative FNAC is performed, the pathologist in charge should be advised accordingly. In addition, patients should be informed about this infrequent risk before undergoing the procedure.