We report a patient with a patellar metastasis from a malignant melanoma. Only 16 other cases have been previously described in detail in the literature. A lyric lesion in the patella is most often caused by a benign turnout, but a primary or secondary malignant turnout has to be excluded.
R~sum~. Nous rapportons un cas de mdlanome malin traduit par une mdtastase rotulienne, sans 6volution clinique pr6alable de la 16sion primitive. La revue de la littdrature n' a permis de retrouver que 16 cas de mdtastase rotulienne histologiquement prouvde et ddcrite en ddtails. Une 16sion lytique de la rotule correspond dans la majorit6 des cas ~ une tumeur bdnigne, mais 1 'dventualit~ d'une tumeur maligne primitive ou d'une localisation mdtastatique secondaire ne peut 6tre exclue.
Case report
A woman, aged 65 years, was admitted to hospital with pain in the front of the right knee which had gradually increased over the previous 4 months. She had been unable to bear weight on her leg for a short period. There was no injury and no relevant past medical history. A radiograph one month before admission showed only slightly reduced bone density in the patella.
The right knee was swollen, red, warm and tender with almost no movement. Her right quadriceps was wasted.
A slightly raised, partly ulcerated, brown skin lesion, 1 cm across, was noticed on her right shoulder. She said this had been present since birth and had not changed in size, or caused symptoms, for 26 years.
The white cell count was raised to 17.5 x 109/litre and plasma viscosity to 1.98.
A radiograph of the right knee showed a lytic lesion on the lateral side of the patella; the cortex was intact and there was no periosteal reaction (Fig. 1). A chest radiograph showed two large basal opacities suggestive of metastases.