[Clinical and morphological characteristics of parathyroid carcinoma]

Multiple Metastases of Parathyroid and Papillary Thyroid Carcinoma in a Female Patient Treated with Long-Term Hemodialysis

Parathyroid cancer is a rare, clinically aggressive malignancy with a prevalence of approximately 0.005% relative to all carcinoma cases and 1-5% among patients with primary hyperparathyroidism. Prognosis largely depends on the extent of the primary surgery. Non-radical surgical treatment increases the risk of local and distant metastases of the parathyroid cancer associated with limited treatment options. The combination of thyroid and parathyroid disorders has been described rather well for the general population; however, cases of parathyroid and thyroid carcinoma in the same patient are extremely rare (1 case per 3000 patients with parathyroid disorders). We present a rare clinical case of combination of parathyroid and thyroid cancers with metastases of both tumors to the neck lymph nodes in a woman with a mutation in the MEN1 gene (NM_130799.2): c.658T > C p.Trp220Arg (W220R), who has been exposed to radiation for 20 years before diagnosis of thyroid cancer and received renal replacement therapy with long-term hemodialysis before the diagnosis of parathyroid cancer. The patient underwent several surgeries because of metastases of the parathyroid cancer in the neck lymph nodes. Surgeons used intraoperative navigation methods (single-channel gamma detection probe, Gamma Probe 2, and fluorescence angiography with indocyanine green (ICG)) to clarify the volume of surgery. Currently, the patient is still in laboratory remission, despite the structural recurrence of tumors.

[Sporadic primary hyperparathyroidism with multiple parathyroid adenomas]

Multiple lesions of the parathyroid glands (PTG) in primary hyperparathyroidism (PHPT) can be sporadic or develop as part of hereditary syndromes, manifesting at young age. There the description of a severe sporadic PHPT with big parathyroid neoplasms in the young patient is presented. Clinical data made it possible to suspect MEN-1 syndrome or parathyroid carcinomas; however, mutations CDKN, CDC73, MEN1 were excluded. The patient underwent removal of three identified tumors: benign adenomas of the left PTG and hyperplasia of the right one. Postoperative hypocalcemia and severe hungry bone syndrome required the administration of vitamin D and calcium carbonate preparations. However, a year after the operation, a «mild» recurrent disease was confirmed. Taking into account the patient's refusal to reoperation and a significant improvement of the target organs state, active observation was continued. The patient needs further careful dynamic monitoring by specialists in order to timely identify indications for repeated surgical treatment to improve the life quality and span.

[Neuroendocrine markers in parathyroid tumors]

The parathyroid glands (PTGs) are a key regulator of calcium and phosphorus metabolism in the human body. In terms of their, morphological and immunophenotypic characteristics, PTGs are neuroendocrine organs, and their neoplasms are neuroendocrine tumors. These neoplasms include adenoma and cancer; in addition, glandular hyperplasia may develop, which is most characteristic of multiple endocrine neoplasia (MEN1, MEN2a, and MEN4) syndromes. The morphological characteristics of pathologically altered PTGs in MEN syndromes are variable. The analysis and generalization of knowledge about the features and expression of various immunohistochemical markers in PTG tissue in health and in diseases are useful in the practical work of not only pathologists, but also clinicians of various specialties.