Brain tumors of diverse germinal origin arising in juxtaposition. Report of three cases.

P a t i e n t s w i t h mu l t ip l e b r a i n t u m o r s have always been a top ic of in te res t . Several categories of cases have b e e n descr ibed. These include: t u m o r s of single cell t y p e such as mul t ip le men ing iomas in t he same p a t i e n t ; 2 mixed gl iomas which seem to e m b o d y subd iv i s ions of different histological s t ruc tures , such as a s t r o c y t o m a and oligodendrogl ioma, fo rming p a r t s of the same t u m o r ; less c o m m o n are t he mu l t i p l e t u m o r s of different germ i n a l origins such as men ing iomas a n d as t rocy tomas.1,6,10,12 T h e l a t t e r m a y occur i ndependen t ly of e ach o the r in t h e s ame hos t a n d several ins tances of th i s p h e n o m e n o n h a v e been repor ted. W h e n these t u m o r s occur in juxtaposi t ion , the ques t ion of e t iological re la t ionship m u s t be ra ised; a n d when b o t h t u m o r s are ma l ignan t , the s i tuat ion is still more p rovoca t ive . Several cases of th i s t y p e have p rev ious ly b e e n reported. 3,4,7,9 T h e usua l i n t e r p r e t a t i o n has been t h a t a secondary m a l i g n a n t g l ioma tous r eac t ion was set up b y the p r i m a r y sa rcoma. Our r e p o r t concerns 3 cases of j u x t a p o s e d m a l i g n a n t t u m o r s of different germ i n a l origins; a t leas t 1 case demons t r a t e s t h a t a g l iob las toma was t he p r i m a r y tumor .