Collision tumor: a parathyroid adenoma unveiling subclinical widespread breast carcinoma: a case report

Parathyroid metastases from breast carcinoma are rare, although more frequent than primary malignancies of the parathyroid gland. This case highlights the need to consider metastatic involvement in cases of parathyroid adenoma, particularly in patients with a history of malignancy. Further research is warranted to elucidate the mechanisms underlying tumor-to-tumor metastases and to assess its impact on clinical management and prognosis.