Table 2: Histological comparison between SA and RAA.

GradeArchitectureDepth of involvement
(breast only)

SA
( )
High: 32/37
(86.5%)
V: 10/37 (27%)
So: 8/37 (21.6%)
Si: 5/37 (13.5%)
S/E: 4/37 (10.8%)
Other: 10/37 (27%)
Dermis: 1/5 (20%)
Parenchyma: 4/5 (80%)

RAA
( )
High: 7/9
(77.8%)
V: 5/9 (55.6%)
So: 1/9 (11.1%)
S/E: 3/9 (33.3%)
Dermis: 4/5 (80%)
Parenchyma: 1/5 (20%)

V: vasoformative, So: solid, Si: sieve, S/E: solid/epithelioid.