Accumulation of 99mTc methylene diphosphonate in malignant pleural and ascitic effusion.

Increased accumulation of radioactivity was observed in malignant pleural and ascitic effusion as to a patient with stomach cancer and in malignant pleural effusions as to 2 patients (1 with breast cancer and another with lung cancer) during the performance of routine whole-body bone scans with 99mTc methylene diphosphonate. This finding should strongly suggest malignancy.