Association of primary hyperparathyroidism and humoral hypercalcemia of malignancy in a patient with clear cell renal carcinoma.
Hypercalcemia is found frequently in patients with cancer. Besides the etiology related to the malignancy, other causes should be considered in the differential diagnostic, as primary hyperparathyroidism, granulomatous diseases and the use of thiazide diuretics. We present a case report of a severe hypercalcemia due to a rare association and review the relevant literature. A female patient, 57 years old, sent to the Endocrinology Service of Hospital das Clínicas da Universidade do Paraná (SEMPR) in order to investigate severe hypercalcemia with frequent need of hospitalization. The patient was in chemotherapy treatment for recurrence of clear cell renal cancer. During the investigation she presented high level of parathyroid hormone (PTH) and parathyroid scintigraphy suggestive of hyperplasia/ adenoma of parathyroid, histopathological diagnosis was confirmed after parathyroidectomy. After surgery the patient presented undetectable levels of PTH. However, she continued with progressive increase of serum calcium, with no signs of bone metastases or change in vitamin D metabolism. The investigation showed high levels of PTH-related protein (PTHrP), leading us to the diagnosis of hypercalcemia of malignancy. The patient presented severe hypercalcemia due to the rare association of primary hyperparathyroidism and humoral hypercalcemia of malignancy due to secretion of PTHrP by tumor cells. The presence of isolated primary hyperparathyroidism, as a cause of hypercalcemia in cancer patients, has been described in approximately 5-10% of the patients. However, the association of primary hyperparathyroidism and humoral hypercalcemia of malignancy (which means with concomitant elevation of PTH and PTHrP) is rare, only three cases have been described in the literature.
Hospital de Clínicas, Universidade Federal do Paraná, Curitiba, PR, Brazil.
Letícia da Silva
Lda S
Gomes
Hospital de Clínicas, Universidade Federal do Paraná, Curitiba, PR, Brazil.
Carolina A M
CA
Kulak
Hospital de Clínicas, Universidade Federal do Paraná, Curitiba, PR, Brazil.
Tatiana Munhoz da Rocha Lemos
TM
Costa
Hospital de Clínicas, Universidade Federal do Paraná, Curitiba, PR, Brazil.
Evandro Cezar Guerreiro
EC
Vasconcelos
Hospital de Clínicas, Universidade Federal do Paraná, Curitiba, PR, Brazil.
Maurício de
Md
Carvalho
Hospital de Clínicas, Universidade Federal do Paraná, Curitiba, PR, Brazil.
Victoria Zeghbi Cochenski
VZ
Borba
D002118:Calcium / Q000097:blood*; D002292:Carcinoma, Renal Cell / Q000097:blood* / Q000000981:diagnostic imaging; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D006934:Hypercalcemia / Q000000981:diagnostic imaging; D049950:Hyperparathyroidism, Primary / Q000150:complications* / Q000000981:diagnostic imaging; D007680:Kidney Neoplasms / Q000097:blood* / Q000000981:diagnostic imaging; D008875:Middle Aged; D010257:Paraneoplastic Syndromes / Q000000981:diagnostic imaging; D011877:Radionuclide Imaging; D035583:Rare Diseases / Q000097:blood
D002118:Calcium