Introduction: breast implants have been used to correct the size and the form of a breast in post-mastectomy breast reconstruction, for correcting congenital defects and deformities or for purely aesthetic breast augmentation. Silicone breast implants were introduced in the 1960s. They are non without complications, like rupture is or silicone gel bleeding. Materials and methods: the authors present the case of 50 patients, aged 45-55, who presented to our attention after 15 (+ 5) years of the application of silicone breast implant for the appearance of lumps under the skin in the armpit area. These were palpable, painless except on palpation. The patients reported burning in the affected area, but no other symptoms. Results: considering the presence in each of them of silicone implants, and assuming a possible allergic basis, the authors performed a patch test series SIDAPA produced by F.I.R.M.A Spa, Firenze, ultrasound and MR and blood tests. In all patients the allergy test (patch test) were negative, ultrasound and MR have shown that no hearing was damaged or broken. Blood test showed no abnormalities. Discussion: comparing the authors’ study with other similar works in the literature, they noted that the reported cases of hypersensitivity type 4 silicone prosthesis was not only initially accompanied by specific symptoms such as urticaria and blistering, but mostly it was found to be a net positive patch test. The absence of urticaria, the low values of IgE and total negativity of patch test confirmed the purely inflammatory nature of the lesions in our patients.