Fortunately, in the present case, to our surprise, despite the hypercalcemic crisis with markedly elevated levels of calcium and PTH and the exceptionally firm tumor found during surgical excision, the histological examination established the diagnosis of a GPA measuring 5.4 cm x2.3 and weighting 11 g, with no atypias, positive parafibromin staining or negative Ki67 and p53 staining. Here, MKI67 is linked to neoplasm.