Sonographical diagnosis of metastatic renal cell carcinoma to the head andneck region.

In the area of the head and neck metastases from distant primary tumours ar e rare in comparison to the common squamous cell carcinomas of the upper re spiratory and digestive tract. Thus correct preoperative diagnosis may be d ifficult. Two cases with distant metastases of renal cell carcinoma to the head and neck region are presented in this report. In a 60-year-old male pa tient, diagnostic evaluation of unilateral epistaxis revealed a radioopacit y of the maxillary sinus, six months after removal of a renal cell carcinom a. In the second case a slowly progressive indolent swelling of the left ne ck developed in a 56-year-old man six years after resection of a renal cell carcinoma and two years after surgical treatment of a pancreatic carcinoma . Following clinical examination, modern imaging techniques with special em phasis on colour Doppler sonography with a Siemens Quantum 2000 were used f or diagnostic evaluation in both patients. Sonography of metastatic renal c ell carcinoma to the maxillary sinus revealed complete opacity of the antru m. The cervical mass proved to the inhomogeneous and hypoechogenic and was difficult to distinguish from the lower parotid lobe and the vessel sheath. A common feature of both tumours was a high degree of perfusion which coul d be confirmed by superselective angiography. The histological examination of the surgical specimen showed an isolated metastasis of a renal cell carc inoma in both cases. In patients with a history of renal cell carcinoma the possibility of distant spread to the head and neck region should be taken into account even after a long period of complete remission, Colour Doppler sonography facilitates the distinction between the normally well perfused secondary tumours and squamous cell carcinomas which usually only have a mi nimal blood supply. Because of the high risk of profuse bleeding a biopsy s hould only be performed in the operating theatre.