(153)Sm-lexidronam (EDTMP) is a therapeutic radiopharmaceutical used for palliation of pain resulting from osseous metastatic disease.
Methods: We recently treated with (153)Sm-EDTMP a patient who had extensive osseous metastases and malignant ascites requiring intermittent drainage from an indwelling catheter. Because we could find no useful data regarding quantification of accumulation of this agent within ascites, we opted to assay the fluid after treatment.
Results: The measured ratio of (153)Sm-EDTMP activity in peritoneal fluid (1.71 L) relative to injected dose was 0.01% (i.e., trivially above background level).
Conclusion: To our knowledge, this represents the first published measurement of (153)Sm-EDTMP accumulation within peritoneal fluid. This information may be useful to the nuclear medicine community since malignant ascites is not uncommon in patients with widely metastatic carcinoma and such patients may be referred for (153)Sm-EDTMP therapy.