Siliconomas mimicking cancer

Introduction: Silicone breast implants are widely used for breast augmentation and breast reconstruction following mastectomy. Implant rupture has specific radiological signs. With the advent use of new imaging technique such as positron emission tomography (PET) computed tomography (CT) and magnetic resonance imaging (MRI) of the breast, these signs may simulate malignancy. Patients and methods: We retrospectively reviewed four cases of patients with silicon breast implants who arrive to the mammography clinic for further evaluation of a suspected malignant process demonstrated on either PET CT or breast MRI. Results: Two cases were of PET CT performed for routine oncology follow-up of breast cancer. On both, the PET CT demonstrated multiple-spread benign silicone granulomas manifesting as multiple masses having an increase fluorodeoxyglucose (FDG) uptake. One case of a new mass was demonstrated as a suspicious mass on the dynamic sequences on MRI of the breast. Ultrasound-guided biopsy demonstrated benign tissue response to silicone. One case demonstrated bilateral ruptured breast implants on breast MRI, as well as bilateral axillary and mediastinal lymphadenopathy. Eventually, the patient underwent bronchoscopy for pulmonary workup of dry cough, revealing sarcoidosis. Conclusion: Silicone granulomas can manifest as masses with suspicious morphology and enhancement dynamics on breast MRI or with increased FDG uptake on PET CT. The presence of silicone implants and awareness of the possibility of a rupture and formation of silicone granulomas may help in facilitating a correct diagnosis.