[Mammographic, magnetic resonance imaging and clinicopathological characteristics of primary breast lymphoma].

Objective: To analyze the mammographic, MRI, and clinicopathological characteristics of primary breast lymphoma (PBL).
Methods: Clinicopathological characteristics were retrospectively reviewed and analyzed in 32 patients with histopathologically proven PBL. All cases were female (mean age, 50 years; median age 46 years; range, 30-68 years).
Results: In the 32 cases, there were bilateral tumors in 5 cases and 27 cases of unilateral involvement. The patients presented with a painless mass in 25 cases and with pain in 7 cases. Rapid enlargement was observed in 6 cases. Mammograms of 17 tumors showed a round, circumscribed mass with high density or iso-density in 9, asymmetry in 7 and no abnormality was found in one. 37 lesions were detected on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in 29 patients, among which 25 (67.6%) lesions appeared as enhancing masses and 12 (32.4%) lesions as non-mass enhancements. All lesions showed iso- or hypo-intense signal on the T1WI and hyper-intense signal on the T2W1. Analysis of the enhancing masses based on the 2013 ACR BI-RADS lexicon revealed that among the mass descriptors in 25 lesions, the most common features were circumscribed or irregular margin in 24 (96.0%) and homogeneous internal pattern in 19 (76.0%). Of the 12 non-mass enhancing lesions, the most common descriptors included regional or multiple regional distribution in 6 (50.0%), and heterogeneous internal pattern in 8 (66.7%). The tumors showed early enhancement with penetrating vessels on DCE-MRI in 16 lesions, associated with skin thickening in 14, and axillary lymphadenopathy in 19. The time-signal intensity curve (TIC) in 14 patients was mainly of type Ⅲ (7/14, 50.0%).
Conclusions: Some imaging features may alert the diagnosis of primary breast lymphoma, but final diagnosis depends on histopathology. Early diagnosis is helpful for selecting appropriate treatment regimens.