Introduction/Background Tall cell carcinoma of the breast with reversed polarity (TCCRP) is a rare subtype of papillary carcinoma recently recognized as a distinct entity on the fifth edition of the WHO classification of breastHere we aim to hilight the histipathological feautures of this rare entity

Methodology We retrospectively report the first case of TCCRP of the breast diagnosed and treated in the Institut of Salah Azaiez in 2022

Results We report the case of a 45 year woman with no family history of cancer who suffered from bilateral mastodynia. There were no nodules or mass palpated on physical exam of the breasts and axillary region.The screening mammography showed an irregular hypoechoic mass of the right breast of 17*10 mm, classified as 4B. The core biopsy specimen revealed a complexe nodular lesion.The mass was surgically excised and the pathological report revealed a TCCRP of the breast PR and ER were negative as well as the HER-2. The Ki-67% proliferative index was around 10%.The patient underwent lymph sentinel lymph node biopsy as treament and was proposed for radiotherapy

Conclusion TCCRP is a rare entity with histological features that mimic the papillary thyroid carcinoma. It is usually a triple-negative tumor, negative to thyroid transcription factor 1 and thyroglobulin with a low potentiel for malignancy and a good prognosis.Wide excision is the keystone of the treatement. However, chemotherapy and radiotherapy are still controversal due to lack of evidence.