Endocrine Abstracts

JOINT3890

Introduction: The association between primary hyperparathyroidism (PHPT) and neoplasia is well described in multiple endocrine neoplasia (MEN). However, its association with malignant solid tumors remains rarely reported. We present the case of a malignant renal tumor diagnosed simultaneously with PHPT

Case Report: A 58-year-old female patient with a history of diabetes and hypertension was hospitalized for management of severe hypercalcemia due to biologically confirmed PHPT, with a parathyroid hormone (PTH) level of 205 pg/mL, hypercalcemia at 3 mmol/l, hypophosphatemia at 0.56 mmol/l and vitamin D deficiency (11.2 ng/mL). She had no family history suggestive of multiple endocrine neoplasia. A cervical ultrasound revealed a 43 mm right superior parathyroid adenoma, along with two thyroid nodules classified as EU-TIRADS 2 and 3. Additionally, physical examination revealed abdominal collateral venous circulation and a left lumbar mass corresponding, on ultrasonography, to a solid-cystic lesion in the lower pole of the left kidney, measuring 11×10×12 cm, highly suspicious for malignancy. Plasma metanephrines and PTH-related peptide (PTHrP) levels were negative. The patient underwent a left lobisthmectomy and parathyroidectomy of the left inferior and right superior glands, leading to normalization of calcium-phosphorus balance postoperatively. Histopathological analysis confirmed hyperplasia of the left inferior and right superior parathyroid glands, as well as with two left vesicular thyroid adenomas. Subsequently, she underwent a left nephrectomy, and histopathological examination revealed a 13 cm clear cell renal cell carcinoma, classed pT2bNxM0 currently under supervising.

Discussion: It is possible that this association is a coincidence. However, that there might be an interaction between the two conditions, particularly due to the production of cytokines, growth factors, or other biologically active molecules that affect both the parathyroid glands and renal tissue. In the literature, there have been a few reported cases where patients with PHPT developed renal carcinoma, often after the treatment of hyperparathyroidism. It remains to be determined whether this association is coincidental or if there is an underlying relationship that has not yet been fully elucidated.