Solitary Obstructing Plasmacytoma of the Colon

ALTHOUGH extraskeletal tumor masses are not infrequently found in disseminated multiple myeloma, solitary plasmacytomas localized to a visceral organ are unusual. Most frequently, they are localized to the upper respiratory tract. 1 Plasmacytomas of the colon are exceedingly rare; only seven cases have been reported previously, 2 and in most there has not been sufficient documentation to exclude disseminated myeloma. This case represents the first instance, to our knowledge, in which a truly solitary plasmacytoma caused intestinal obstruction. It also serves to emphasize the need to carefully evaluate such cases to exclude generalized involvement. Report of a Case A 76-year-old, Italian-born, retired railroad worker was admitted to the Montefiore Hospital, University of Pittsburgh, for abdominal pain. The patient had been in excellent health until two weeks prior to admission, when he had suddenly experienced lower abdominal pain. This had subsided within 24 hours but recurred at two-to three-day intervals. On