Non-functioning parathyroid gland carcinoma: case report.

Parathyroid gland carcinoma is a rare malignancy. The tumor is mostly functioning, causing severe hyperparathyroidism, with high serum calcium level and severe bone disease. Non-functioning parathyroid carcinomas are extremely rare. We report on a 60-year-old male patient admitted to ENT Department due to a large neck tumor mass compressing the thyroid and trachea. Preoperatively, thyroid hormone, parathyroid hormone (PTH) and calcium serum levels were normal. The following immunohistochemical markers (DAKO, Denmark) were used: bcl-2; CD-10; Chromogranin-A; Cyclin-D1; EMA; Ki-67; Mdm-2; p-53; PGP-9,5; RCC; Synaptophysin; Thyroglobulin; and TTF-1. Immunohistochemical analysis indicated the diagnosis of a primary parathyroid gland carcinoma. Tumor cells showed diffusely positive immunohistochemical staining with chromogranin-A and PGP-9,5, positive staining of variable intensity with synaptophysin, and weakly positive reaction with EMA. Also, the cytoplasm of tumor cells was diffusely positively stained with bcl-2, while the nuclei showed positive reaction with p-53 oncogene and TTF-1. The remaining markers (CD-10, cyclin-D1, Ki-67, Mdm-2, RCC and thyroglobulin) were negative. Four years after the surgery, the patient died from renal carcinoma pulmonary metastases and liver cirrhosis complications. In conclusion, non-functioning parathyroid gland carcinoma is a very rare disease. Detailed immunohistochemical analysis is needed to distinguish it from other thyroid and parathyroid neoplasms and metastatic carcinoma. Surgical treatment is presently the best mode of therapy.