Purpose: This study was done to identify the typical magnetic resonance (MR) imaging findings of inflammatory breast carcinoma (IBC) in comparison with noninflammatory locally advanced breast carcinoma (LABC).
Materials and methods: MR images of 30 patients with IBC (T4d) were compared with those of a cohort of 30 patients with LABC (T3/T4a-c). The age distribution was approximately equal in the two groups. MR images were assessed for the following features: skin thickening (>4 mm), skin oedema, architectural distortion, enhancement pattern (mass-like/non-mass-like), time-signal intensity curve (continuous-persistent type/wash-out type), skin enhancement. Fisher's exact text was used to compare MR imaging appearances of IBC and LABC (significant p value <0.05).
Results: Skin involvement and enhancement pattern differed between groups: skin thickening was present in 16/30 IBC (53%) vs 8/30 LABC cases (27%, p=0.06), skin oedema was present in 26/30 IBC (87%) vs 8/30 LABC (27%, p < 0.0001), and skin enhancement in 10/30 IBC (33%) vs 2/30 LABC (7%, p=0.02); non-mass-like enhancement was present in 22/30 IBC (73%) vs 12/30 LABC (40%, p=0.02).
Conclusions: IBC is a distinct clinical and pathological entity resulting in typical MR imaging features. Skin changes (thickening, oedema, enhancement) related to neoplastic involvement of the dermal lymphatics are suggestive of IBC and should prompt a skin biopsy to confirm or rule out the diagnosis.