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[A rare case of tumor-to-tumor metastasis: secondary deposits of pulmonary adenocarcinoma in a secretory meningioma].

OBJECTIVE
To report a rare case of tumour-to-tumour metastasis with differential diagnostic considerations.


METHODS AND RESULTS
We report the operation of a Sylvian fissure secretory meningioma in a 48 year-old woman. The tumour was suspicious of a metastasis related to a pulmonary adenocarcinoma operated 4 months before. Histopathology confirmed metastatic adenocarcinoma in a secretory meningioma.


CONCLUSIONS
Both secretory meningioma and tumour-to-tumour metastasis are rare, and to our knowledge this is the first report of such a rare coincidence. Secretory meningioma can simulate metastases both clinically (extensive oedema, space occupation, carcinoembryonic antigen secretion) and pathologically (secretory inclusions, positivity for cytokeratin 7 and carcinoembryonic antigen and negativity for vimentin), and therefore may cause a special differential diagnostic dilemma.