Introduction/Background Primary squamous cell carcinoma (SCC) is a very rare malignancy of the breast, that represents only 0.1 to 2% of breast cancers.

Methodology This is a retrospective study of 3 patients treated for squamous cell carcinoma of the breast between 1995 and 2018, at the oncological radiotherapy department in the University Hospital Farhat Hached, Sousse.

Results When diagnosed, the patients were 36, 62, and 69. The reason for seeking consultation was a nodule in the left breast in the case of 2 patients and mastalgia in the right breast in the third. Mammography showed suspicious opacities, ranging from 15 to 34 mm, in the 3 patients with ipsilateral axillary adenopathy in 1 patient. A biopsy was performed and the anatomical pathology indicated breast SCC in the three patients. The extension assessment was negative. One patient underwent neoadjuvant chemotherapy, followed by an intervention of the type Patey. The other 2 were operated on immediately: lumpectomy-axillary dissection in one case and mastectomy axillary dissection in the other. Adjuvant chemotherapy was performed on these 2 patients. The anatomical pathology study showed a damaged lymph node in 2 patients, and the limits were healthy in 2 cases and permeated in the third. Hormone receptors were negative in 1 patient and unknown in the other 2. The 3 patients underwent radiotherapy at a dose of 52.2 Gy (1.8 Gy per fraction) with a boost of 14.4 Gy on the primary tumor bed area in 1 patient. The median follow-up was of approximately 10 years. One patient died from an array of pulmonary and cerebral metastases. The other two are being monitored and in complete remission.

Conclusion Primary squamous cell carcinoma of the breast is rare. The clinical and radiological aspects are not specific. Treatment is based on the surgical option. The prognosis remains controversial.