calcitriol and Paraneoplastic-Syndromes

Topics: Adult; Aged; Calcium; Child; Female; Humans; Jaw Neoplasms; Male; Middle Aged; Mouth Neoplasms; Osteomalacia; Paraneoplastic Syndromes; Parathyroid Hormone; Vitamin D

We report two infants with infantile fibrosarcoma (IFS) complicated by severe hypercalcemia. Assessment demonstrated suppressed parathyroid hormone and 1,25-dihydroxyvitamin D levels with elevated circulating levels of parathyroid hormone related protein, indicating the diagnosis of humoral hypercalcemia of malignancy (HHM). HHM is a paraneoplastic syndrome rarely associated with pediatric malignancies. Hypercalcemia manifested clinically with neurologic symptoms and soft tissue calcium deposition and required aggressive management with intravenous fluids, diuretics, and supplemental electrolytes. Following treatment with neoadjuvant chemotherapy, serum calcium levels precipitously declined requiring calcium repletion. These cases highlight the improvement of hypercalcemia secondary to HHM following chemotherapy.

Topics: Calcium; Female; Fibrosarcoma; Humans; Hypercalcemia; Infant, Newborn; Male; Neoadjuvant Therapy; Paraneoplastic Syndromes; Parathyroid Hormone; Vitamin D

Malignancy is the most common cause of hypercalcaemia in the inpatient setting. Most cases are caused by tumour production of parathyroid hormone-related protein and osseous metastases. In less than 1% of cases, hypercalcaemia is driven by increased production of 1,25-dihydroxyvitamin D (1,25(OH)

Topics: Aged; Carcinoma, Neuroendocrine; Female; Humans; Hypercalcemia; Paraneoplastic Syndromes; Uterine Cervical Neoplasms; Vitamin D

Topics: Adult; Fibroblast Growth Factor-23; Fibroblast Growth Factors; Foot Diseases; Humans; Hypophosphatemia; Male; Neoplasm Proteins; Neoplasms, Connective Tissue; Osteomalacia; Paraneoplastic Syndromes; Skin Neoplasms; Toes; Vitamin D

Seminomas have been rarely associated with malignant hypercalcemia. The responsible mechanism of hypercalcemia in this setting has been described to be secondary to 1,25-dihydroxyvitamin D secretion. The relationship with PTHrP has not been determined or studied.The aim of this study is to describe and discuss the case and the pathophysiological mechanisms involved in a malignant hypercalcemia mediated by 1,25-dihydroxyvitamin D and PTHrP cosecretion in a patient with seminoma.. A 35-year-old man was consulted for assessment and management of severe hypercalcemia related to an abdominal mass. Nausea, polyuria, polydipsia, lethargy and confusion led him to the emergency department. An abdominal and pelvic enhanced CT confirmed a calcified pelvic mass, along with multiple retroperitoneal lymphadenopathy. Chest x-ray revealed "cannon ball" pulmonary metastases. The histopathology result was consistent with a seminoma. Serum calcium was 14.7 mg/dl, PTH was undetectable, 25-dihydroxyvitamin D was within normal values and PTHrP and 1,25-dihydroxyvitamin were elevated (35.0 pg/ml, and 212 pg/ml, respectively). After the first cycle of chemotherapy with bleomycin, etoposide and cisplatin, normocalcemia was restored. Both PTHrP and 1,25-dihydroxyvitamin D, dropped dramatically to 9.0 pg/ml and 8.0 pg/ml, respectively.. The association of seminoma and malignant hypercalcemia is extremely rare. We describe a case of a patient with a seminoma and malignant hypercalcemia related to paraneoplastic cosecretion of 1,25-dihydroxyvitamin D and PTHrP. After successful chemotherapy, calcium, PTHrP and 1,25-Dihydroxyvitamin D returned to normal values.

Topics: Adult; Humans; Hypercalcemia; Lung Neoplasms; Male; Paraneoplastic Syndromes; Parathyroid Hormone; Parathyroid Hormone-Related Protein; Prognosis; Seminoma; Testicular Neoplasms; Vitamin D

Oncogenic osteomalacia, or tumour-induced osteomalacia (TIO), is a rare paraneoplastic syndrome characterised by hypophosphataemia, phosphaturia, inappropriately low serum levels of 1,25-dihydroxyvitamin D for hypophosphataemia. TIO is caused by mesenchymal tumours that secrete phosphaturic substances, leading to increased renal wasting of phosphates. These tumours are very small in size and grow slowly. Localisation of these tumours has always been difficult with the available biochemical and imaging techniques. At times, despite all efforts, the tumour could not be localised. We report our experience with a 42-year-old woman with TIO where whole-body magnetic resonance imaging could not localise the tumour, a scapular haemangiopericytoma. PET/CT was helpful in the localisation of the tumour which, when surgically removed, resulted in the normalisation of biochemical parameters with clinical improvement.

Topics: Adult; Bone Diseases; Contrast Media; Female; Fluorodeoxyglucose F18; Hemangiopericytoma; Humans; Magnetic Resonance Imaging; Osteomalacia; Paraneoplastic Syndromes; Positron-Emission Tomography; Radiopharmaceuticals; Scapula; Tomography, X-Ray Computed; Vitamin D

Oncogenic osteomalacia (OOM) is characterised by tumour production of fibroblast growth factor 23 (FGF23) that results in hypophosphataemia and renal phosphate wasting, reduced 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) synthesis and osteomalacia. Here, we demonstrate the roles of serum FGF23 and 1,25(OH)2D3, together with the lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1), as biomarkers for OOM. A previously well 52-year-old man presented with a 2-year history of generalised musculoskeletal pain and proximal myopathy. He had hypophosphataemia, elevated serum alkaline phosphatase activity, low serum 1,25(OH)2D3 and a reduced tubular maximum of phosphate/glomerular filtration rate. These findings indicated a diagnosis of OOM, but magnetic resonance imaging (MRI) and octreotide scintigraphy did not identify any tumours. Treatment with oral phosphate and calcitriol resolved the symptoms and biochemical abnormalities within 6 months. Four years later, he relapsed whilst on treatment with oral phosphate and calcitriol. Serum FGF23 concentration was elevated and MRI identified a 2 cm tumour within Hoffa's fat pad of the left knee. Removal of the tumour resulted in a complete resolution of symptoms and normalisation of the serum biochemical abnormalities including serum FGF23. Histology demonstrated a phosphaturic mesenchymal tumour, mixed connective tissue variant (PMTMCT), which revealed immunostaining with anti-LYVE-1 antibody and hence the presence of lymphatic vessels. Serum FGF23 and 1,25(OH)2D3 were found to be reliable biomarkers for OOM. In addition, the demonstration of lymphatics in the PMTMCT helps to distinguish this tumour from most typical benign haemangiomas.

Topics: Administration, Oral; Alkaline Phosphatase; Biomarkers; Biomarkers, Tumor; Bone Neoplasms; Calcitriol; Chondrosarcoma, Mesenchymal; Endothelium, Vascular; Fibroblast Growth Factor-23; Fibroblast Growth Factors; Humans; Hyaluronan Receptors; Hypophosphatemia; Knee; Lymphatic Vessels; Male; Middle Aged; Osteomalacia; Paraneoplastic Syndromes; Phosphates; Predictive Value of Tests; Vitamin D