Objective: Papillary carcinoma of the female breast may exhibit a broad phenotype. We present an unusual case of a pseudoencapsulated invasive papillary carcinoma featuring transitional cell features. Method: A specimen of internal right female breast biquadrantectomy was routinely processed and a panel of antibodies applied on paraffin tissue section. Results: Grossly, the specimen showed a 12.5 cm cystic lesion with fibrino-hematic material and multiple pinkish-grey papillary structures, the largest measuring 4 cm. The histological examination revealed a malignant epithelial papillary proliferation reminiscent of transitional cell carcinoma, with high nuclear grade, frequent mitotic figures, multiple areas of invasion and rare necrotic foci. Tumor cells were immunoreactive for p63, 34βE12 and Ki-67 (90 %) and negative for other stains including HER2/neu, estrogen and progesterone receptors. Our differential diagnosis included a metastasis from a primary urothelial carcinoma, an intraductal papillary lesion, a metaplastic carcinoma and a papillary adnexal neoplasm, all reasonably excluded after careful clinico-pathologic evaluation. Conclusion: Metastatic involvement of the breast is uncommon but it should be considered if tumor phenotype is inconsistent within usual or "special type" breast carcinoma. Yet, some rare primary misleading lesions are difficult to recognize.