Parathyroid cancer (PC) presents clinically as a case of hyperparathyroidism associated with local compression symptoms. The definitive diagnosis of PC is complex as it requires unequivocal criteria of invasion in postoperative biopsy. Given the difficulty in confirming the diagnosis of PC, attempts have been made to address this problem through the search for biomarkers, mainly using immunohistochemistry. Within this theme, the phenomenon of epithelial-mesenchymal transition and cancer stem cells markers have been scarcely studied; and could eventually help discriminate between a diagnosis of parathyroid adenoma or carcinoma. This review presents a clinical approach to the disease; as well as providing a state of the art analysis of basic biomarkers in diagnosis and future projections in this field.