Approach to diagnosis and treatment of hypercalcemia in a patient with malignancy

Assessing the Impact of Comorbid Hypercalcemia on Inpatient Outcomes of Patients With Diffuse Large B-cell Lymphoma During Admission for Chemotherapy

Introduction Diffuse large B-cell lymphoma (DLBCL) may be complicated by hypercalcemia at various stages of treatment. The impact of hypercalcemia on chemotherapy admission outcomes in DLBCL is not well described.  Methods In a retrospective analysis, using the National Inpatient Sample database (2018 - 2020), patients with DLBCL admitted for chemotherapy were dichotomized based on the presence of hypercalcemia. Our primary outcome was all-cause mortality. Secondary outcomes included length of stay (LOS), total charge, rate of acute kidney injury (AKI), tumor lysis syndrome (TLS), hyperkalemia, metabolic acidosis, acute encephalopathy, septic shock, Clostridiodes difficile infection, acute respiratory failure, and venous thromboembolic events (VTE). Results We identified 78,955 patients, among whom 1,375 (1.74%) had hypercalcemia. Hypercalcemia was associated with higher odds of all-cause mortality (aOR:3.05, p-value:0.020), TLS (aOR:8.81, p-value<0.001), acute metabolic encephalopathy (aOR:4.89, p-value<0.001), AKI (aOR:5.29, p-value<0.001), hyperkalemia (aOR:2.84, p-value:0.002), metabolic acidosis (aOR:3.94, p-value<0.001) and respiratory failure (aOR:2.29, p-value:0.007) and increased LOS by 1 day and total charge by 12, 501 USD. Conclusions In patients with DLBCL admitted for inpatient chemotherapy, those with hypercalcemia compared to a cohort without had higher odds of; all-cause mortality, TLS, AKI, acute encephalopathy, acute metabolic acidosis, hyperkalemia, and acute respiratory failure as well as higher LOS and total charge.

Acute Oncologic Complications: Clinical-Therapeutic Management in Critical Care and Emergency Departments

Introduction. It is now known that cancer is a major public health problem; on the other hand, it is less known, or rather, often underestimated, that a significant percentage of cancer patients will experience a cancer-related emergency. These conditions, depending on the severity, may require treatment in intensive care or in the emergency departments. In addition, it is not uncommon for a tumor pathology to manifest itself directly, in the first instance, with a related emergency. The emergency unit proves to be a fundamental and central unit in the management of cancer patients. Many cancer cases are diagnosed in the first instance as a result of symptoms that lead the patient's admittance into the emergency room. Materials and Methods. This narrative review aims to analyze the impact of acute oncological cases in the emergency setting and the role of the emergency physician in their management. A search was conducted over the period January 1981-April 2023 using the main scientific platforms, including PubMed, Scopus, Medline, Embase and Google scholar, and 156 papers were analyzed. Results. To probe into the main oncological emergencies and their management in increasingly overcrowded emergency departments, we analyzed the following acute pathologies: neurological emergencies, metabolic and endocrinological emergencies, vascular emergencies, malignant effusions, neutropenic fever and anemia. Discussion/Conclusions. Our analysis found that a redefinition of the emergency department connected with the treatment of oncology patients is necessary, considering not only the treatment of the oncological disease in the strict sense, but also the comorbidities, the oncological emergencies and the palliative care setting. The need to redesign an emergency department that is able to manage acute oncological cases and end of life appears clear, especially when this turns out to be related to severe effects that cannot be managed at home with integrated home care. In conclusion, a redefinition of the paradigm appears mandatory, such as the integration between the various specialists belonging to oncological medicine and the emergency department. Therefore, our work aims to provide what can be a handbook to detect, diagnose and treat oncological emergencies, hoping for patient management in a multidisciplinary perspective, which could also lead to the regular presence of an oncologist in the emergency room.

Re-Evaluating the Role of PTHrP in Breast Cancer

Parathyroid-hormone-related protein (PTHrP) is a protein with a long history of association with bone metastatic cancers. The paracrine signaling of PTHrP through the parathyroid hormone receptor (PTHR1) facilitates tumor-induced bone destruction, and PTHrP is known as the primary driver of humoral hypercalcemia of malignancy. In addition to paracrine signaling, PTHrP is capable of intracrine signaling independent of PTHR1 binding, which is essential for cytokine-like functions in normal physiological conditions in a variety of tissue types. Pre-clinical and clinical studies evaluating the role of PTHrP in breast cancer have yielded contradictory conclusions, in some cases indicating the protein is tumor suppressive, and in other studies, pro-growth. This review discusses the possible molecular basis for the disharmonious prognostic indications of these studies and highlights the implications of the paracrine, intracrine, and nuclear functions of the protein. This review also examines the current understanding of the functional domains of PTHrP and re-evaluates their role in the unique context of the breast cancer environment. This review will expand on the current understanding of PTHrP by attempting to reconcile the functional domains of the protein with its intracrine signaling in cancer.

An Exciting Case of Acute on Chronic Hypercalcemia in the Setting of Chronic Primary Hyperparathyroidism: A Case Report and Diagnostic Approach

Acute worsening of hypercalcemia in patients with chronic primary hyperparathyroidism can be challenging, and availability bias may mislead physicians to diagnose worsening primary hyperparathyroidism, especially if the parathyroid hormone is also trending higher. We report a case of stage-IV non-Hodgkin's lymphoma which presented as acute worsening of hypercalcemia in a patient with chronic primary hyperparathyroidism.

Essential metals in health and disease

In total, twenty elements appear to be essential for the correct functioning of the human body, half of which are metals and half are non-metals. Among those metals that are currently considered to be essential for normal biological functioning are four main group elements, sodium (Na), potassium (K), magnesium (Mg), and calcium (Ca), and six d-block transition metal elements, manganese (Mn), iron (Fe), cobalt (Co), copper (Cu), zinc (Zn) and molybdenum (Mo). Cells have developed various metallo-regulatory mechanisms for maintaining a necessary homeostasis of metal-ions for diverse cellular processes, most importantly in the central nervous system. Since redox active transition metals (for example Fe and Cu) may participate in electron transfer reactions, their homeostasis must be carefully controlled. The catalytic behaviour of redox metals which have escaped control, e.g. via the Fenton reaction, results in the formation of reactive hydroxyl radicals, which may cause damage to DNA, proteins and membranes. Transition metals are integral parts of the active centers of numerous enzymes (e.g. Cu,Zn-SOD, Mn-SOD, Catalase) which catalyze chemical reactions at physiologically compatible rates. Either a deficiency, or an excess of essential metals may result in various disease states arising in an organism. Some typical ailments that are characterized by a disturbed homeostasis of redox active metals include neurological disorders (Alzheimer's, Parkinson's and Huntington's disorders), mental health problems, cardiovascular diseases, cancer, and diabetes. To comprehend more deeply the mechanisms by which essential metals, acting either alone or in combination, and/or through their interaction with non-essential metals (e.g. chromium) function in biological systems will require the application of a broader, more interdisciplinary approach than has mainly been used so far. It is clear that a stronger cooperation between bioinorganic chemists and biophysicists - who have already achieved great success in understanding the structure and role of metalloenzymes in living systems - with biologists, will access new avenues of research in the systems biology of metal ions. With this in mind, the present paper reviews selected chemical and biological aspects of metal ions and their possible interactions in living systems under normal and pathological conditions.

Disorders of Divalent Ions (Magnesium, Calcium, and Phosphorous) in Patients With Cancer

Disorders of the divalent ions (magnesium, calcium, and phosphorous) are frequently encountered in patients with cancer. Of these, hypomagnesemia, hypocalcemia, hypercalcemia, and hypophosphatemia are seen most commonly. These electrolyte disturbances may be related to the underlying malignancy or due to side effects of anticancer therapy. When caused by a paraneoplastic process, these abnormalities may portend a poor prognosis. Importantly, the development of severe electrolyte derangements may be associated with symptoms that negatively impact quality of life, preclude the administration of critical chemotherapeutic agents, or lead to life-threatening complications that require hospitalization and emergent treatment. In accordance, prompt recognition and treatment of these disorders is key to improving outcomes in patients living with cancer. This review will discuss selected derangements of the divalent ions seen in this population, with a focus on paraneoplastic and therapy-associated etiologies.

Hypercalcemia of malignancy in metastatic esophageal squamous cell carcinoma with simultaneous PTHrP and calcitriol overproduction: A case report with literature review

Introduction and importance

hypercalcemia of malignancy is a severe complication of malignancy and associated with poor prognosis. Four mechanisms are implicated in this metabolic disorder, including excess parathyroid-related peptide secretion, focal osteolysis secondary to bone metastasis or multiple myeloma, excess calcitriol production, and ectopic parathyroid hormone production. Humoral hypercalcemia of malignancy secondary to isolated PTHrP or calcitriol overproduction is known; however, hypercalcemia of malignancy due to simultaneous PTHrP and calcitriol overproduction is less well known.

Case presentation

we report a case of a 63-year-old male who was diagnosed with poorly differentiated esophageal squamous cell carcinoma with simultaneous PTHrP and calcitriol overproduction.

Clinical discussion

while hypercalcemia of malignancy secondary to simultaneous PTHrP and calcitriol secretion has been reported in other solid cancers, this is the first case of humoral hypercalcemia of malignancy secondary to simultaneous PTHrP and calcitriol secretion associated with esophageal cancer. This phenomenon deserves increased recognition as it has both diagnostic and therapeutic consequences. We discuss the current testing algorithm and its limitations in determining the etiology of hypercalcemia of malignancy since it may miss the diagnosis of simultaneous PTHrP and calcitriol production.

Conclusion

we propose a revised testing algorithm for hypercalcemia of malignancy, which may improve the identification of simultaneous overproduction of PTHrP and calcitriol. This new algorithm can better characterize the mechanisms of hypercalcemia of malignancy and more appropriately guide treatment.

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Hypercalcemia of malignancy with simultaneous PTHrP and calcitriol production merits better recognition for both diagnostic and therapeutic purposes.

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A case of hypercalcemia of metastatic esophageal squamous cell carcinoma with simultaneous PTHrP and calcitriol is reported.

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The current testing algorithm and its limitations of hypercalcemia of malignancy is discussed, and a revised one is proposed.

Can conventional clinical chemistry tests help doctors in the monitoring of oncology patients?

The use of laboratory assays in the diagnostic care of oncology patients can markedly increase the efficacy of cancer treatments. Many cancer-specific biomarker assays have been developed. However, the use of these has some limitations due to their cost. Moreover, not every diagnostic laboratory can perform a complete set of these assays. On the other hand, the smart use of conventional clinical chemistry tests could improve the management of cancer. They could be especially valuable tools in the long-term care of patients with a verified diagnosis. In this review, we discuss the utilization of the conventional clinical chemistry assays for the diagnosis, monitoring and prognosis of various oncological diseases. The use of conventional blood tests to assess the levels of chemical elements, metabolites and proteins (including enzymatic activity measurements) in the care of oncology patients is discussed. We have shown that some clinical chemistry assays could be used in the management of distinct kinds of cancer.

Hypercalcemia of Malignancy Attributed to Cosecretion of PTH and PTHRP in Lung Adenocarcinoma

Introduction

Hypercalcemia of malignancy (HCM) portends a very poor prognosis, and no established guidelines exist regarding its management. Most instances of HCM are due to local osteolysis or secretion of parathyroid hormone related-peptide, while less than 1% of all cases are due to ectopic secretion of parathyroid hormone.

Case Report

We present an unusual case of HCM due to proposed cosecretion of both parathyroid hormone and parathyroid hormone-related protein in a 36-year-old man with a poorly differentiated lung adenocarcinoma. The patient’s hypercalcemia was refractory to conventional measures, including intravenous bisphosphonate therapy (zoledronic acid), and was improved with administration of denosumab.

Conclusion

This is the youngest and first case of hypercalcemia of malignancy attributed to cosecretion of PTH and PTHrP from an adenocarcinoma. In refractory cases of HCM, denosumab is a potential option when other conventional measures are unsuccessful.

Multidisciplinary management of metastatic spine disease: initial symptom-directed management

In the past 2 decades, a deeper understanding of the cancer molecular signature has resulted in longer longevity of cancer patients, hence a greater population, who potentially can develop metastatic disease. Spine metastases (SM) occur in up to 70% of cancer patients. Familiarizing ourselves with the key aspects of initial symptom-directed management is important to provide SM patients with the best patient-specific options. We will review key components of initial symptoms assessment such as pain, neurological symptoms, and spine stability. Radiographic evaluation of SM and its role in management will be reviewed. Nonsurgical treatment options are also presented and discussed, including percutaneous procedures, radiation, radiosurgery, and spine stereotactic body radiotherapy. The efforts of a multidisciplinary team will continue to ensure the best patient care as the landscape of cancer is constantly changing.

Study of Adverse Effect Profile of Zoledronic Acid Infusion Among Patients with Cancer: A Retrospective Analysis

Background: Zoledronic acid (ZA) is widely used in the management of cancer-related bone events. It, however, might be associated with serious adverse effects. Objectives: To evaluate ZA adverse effects and changes in biochemical parameters related to ZA toxicities among patients with cancer. Methods: Ninety-eight oncology patients, who were prescribed ZA intravenous (IV) infusion, were interviewed to assess whether they experienced ZA related symptoms, including acute events and serious adverse effects. ZA’s effects on the serum levels of different biochemical parameters were retrospectively assessed by checking patients’ electronic medical records. Results: The most commonly reported adverse effects were: myalgia (48%), bone pain (36.7%), influenza-like symptoms (34.7%), headache (31.6%), and pyrexia (22.45%) with decreasing frequency of such adverse effects upon repeated infusions. Serious side effects including jaw osteonecrosis, cardiac, and renal problems were not reported. A small, but statistically significant reduction in serum calcium, creatinine, and total protein levels was observed upon comparing levels before and after the first IV infusion of ZA (P ≤ 0.031). No significant change was recorded with other serum electrolytes including phosphorus, sodium, potassium, and magnesium as well as urea levels (P ≥ 0.271). No significant difference was determined in terms of final serum levels of all parameters in comparison to pre-treatment (P ≥ 0.059), except for potassium, where a significant reduction was observed (P = 0.003). Notably, the mean values of all parameters were within the normal range. Conclusions: ZA acute events resolved with symptomatic treatment and reduced with repeated IV infusions. ZA appears as a safe treatment modality for skeletal-related events among patients with cancer and the reported adverse effects should not affect patients’ compliance.

Oncological Emergencies from Pathophysiology and Diagnosis to Treatment: A Narrative Review

Oncological emergencies are defined as any acute possible morbid or life-threatening events in patients with cancer either because of the malignancy or because of their treatment. These events may occur at any time during malignancy, from symptoms present to end-stage disease. The aim of this study is the review of urgent conditions results from cancer or cancer treatment side effects that need to be addressed immediately. In this study, a comprehensive and in-depth narrative review was carried out by searching the databases of PubMed, Scopus, Science Direct, Google Scholar with the keywords of "cancer, emergency, metabolic emergency, neutropenic fever" along with the words, "tumor lysis syndrome, chemotherapeutic emergency, diagnosis, treatment " in last two decades. Patients suffering from cancer mostly face the challenges that we are classified in different categories, including metabolic, hematologic, cardiovascular, neurologic, respiratory, infectious, and chemotherapeutic emergencies. These patients mostly complain of headaches, nausea, pain, and fever. In conclusion, knowledge of oncology emergencies and palliative care as part of a team approach is critical for treating cancer patients. In this light, it is pivotal for physicians to focus on the early detection of oncological emergencies. Moreover, training programs for cancer patients help them to timely recognize and report the oncologic emergency symptoms, leading to avoid deleterious consequences and unnecessary healthcare costs as well as improve the quality of life in these patients.

Paraneoplastic syndromes and other systemic disorders associated with neuroendocrine neoplasms

Neuroendocrine paraneoplastic syndromes (PNS) consist of metabolic disorders that accompany benign and malignant neoplasms but remain unrelated to mass effects or invasion by the primary tumor or its metastases. The underlying pathogenesis responsible for PNS usual clinical presentation relies on aberrant production of protein hormones, proteins and other substances by the tumor. Prompt recognition of characteristic signs and symptoms combined with serological identification of key substances may result in early diagnosis of PNS and its underlying malignancy. For these reasons, healthcare professionals should familiarize themselves with tumor-induced hypercalcemia, syndrome of inappropriate antidiuretic hormone, carcinoid syndrome, virilisation syndrome, gynecomastia, acromegaly, Cushing syndrome, osteogenic osteomalacia, tumor-induced hypoglycemia, necrolytic migratory erythema, and watery diarrhea, hypokalemia and achlorydria syndrome. Medical awareness for PNS can improve patient outcomes through earlier administration of cancer therapy and treatment, better symptomatic relief and prolong overall survival.

Diagnosis and Management of Oncologic Emergencies

Oncologic emergencies may be seen in any emergency department and will become more frequent as our population ages and more patients receive chemotherapy. Life-saving interventions are available for certain oncologic emergencies if the diagnosis is made in a timely fashion. In this article we will cover neutropenic fever, tumor lysis syndrome, hypercalcemia of malignancy, and hyperviscosity syndrome. After reading this article the reader should be much more confident in the diagnosis, evaluation, and management of these oncologic emergencies.

Treatment of extreme hypercalcaemia: the role of haemodialysis

A patient with extremely high calcium level of 23.9 mg/dL (5.97 mmol/L) was admitted to our department unconscious with pathological ECG recording, demonstrating shortening of QT interval. The patient was treated by fluid resuscitation, bisphosphonates, salmon calcitonin and steroids. Haemodialysis with low calcium bath had been promptly provided with improvement of consciousness and calcium level. ECG changes disappeared. Subsequent investigations revealed hyperparathyroidism and a large parathyroid adenoma was then surgically removed. Extreme and rapid calcium elevation (parathyroid crisis) is rarely seen in primary hyperparathyroidism and usually is distinctive for malignancy. In the context of acute kidney injury and refractory hypercalcaemia with life-threatening complications (coma, ECG changes with impending danger of arrhythmia), haemodialysis may effectively decrease calcium levels. It should be pointed out that dialysis is an efficient method of treatment of refractory hypercalcaemia, parathyroid crisis, but it is rarely used due to its invasive nature.

A Just-in-Time Learning Based Monitoring and Classification Method for Hyper/Hypocalcemia Diagnosis

This study focuses on the classification and pathological status monitoring of hyper/hypo-calcemia in the calcium regulatory system. By utilizing the Independent Component Analysis (ICA) mixture model, samples from healthy patients are collected, diagnosed, and subsequently classified according to their underlying behaviors, characteristics, and mechanisms. Then, a Just-in-Time Learning (JITL) has been employed in order to estimate the diseased status dynamically. In terms of JITL, for the purpose of the construction of an appropriate similarity index to identify relevant datasets, a novel similarity index based on the ICA mixture model is proposed in this paper to improve online model quality. The validity and effectiveness of the proposed approach have been demonstrated by applying it to the calcium regulatory system under various hypocalcemic and hypercalcemic diseased conditions.

Oncologic Metabolic Emergencies

Cancer and its therapies may lead to several metabolic emergencies that emergency providers (EPs) should be well-versed in identifying and managing. With prompt recognition and treatment initiation in the emergency department, lives can be saved and quality of life maintained. Most oncologic metabolic emergencies occur in advanced cancer states, but some follow initiation of treatment or may be the presenting syndrome that leads to the cancer diagnosis. This article reviews the 2 most emergent oncologic metabolic diagnoses: tumor lysis syndrome and hypercalcemia of malignancy. A discussion on associated cancers and conditions, pathogenesis and pathophysiology, and management recommendations is included.

Cancer-related hypercalcemia in oral cancer

Cancer-related hypercalcemia (CRH) is a critical paraneoplastic disorder in advanced cancer patients. In clinical practice, patients with CRH have a poor prognosis. The medical records of 3198 oral cancer patients with CRH diagnosed at Taichung Veterans General Hospital from 1 January 2003 to 31 December 2015 were reviewed. The criteria for patient enrolment were a diagnosis of hypercalcemia or the use of antihypercalcemia medication. Patients who met any of the following criteria were excluded: use of total parenteral nutrition, incomplete serum calcium data, and unknown date of death. The total incidence of CRH was 6.95‰ per year. A total of 91 patients were enrolled; their median survival time was 28 days. The patients were divided into two groups by survival time, with a cut-off point of 30 days. Reduced serum albumin, leucocytosis, and clodronate use had a statistically significant effect on survival in the univariate analysis (all P<0.05). Forty-five patients (49.5%) had recurrence of CRH, of whom nine died within 30days. These nine patients had a shorter interval to the first episode of CRH recurrence (median 13 days) than those who survived ≥30days (median 28 days) (P<0.001). It was observed that a short interval to the first episode of CRH recurrence is a poor prognostic factor.

Use of cinacalcet and sunitinib to treat hypercalcaemia due to a pancreatic neuroendocrine tumor

Neuroendocrine tumors (NETs) can secrete hormones, including ectopic secretions, but they have been rarely associated with malignant hypercalcemia. A 52-year-old man with a history of diabetes mellitus was diagnosed with a pancreatic tumor. A pancreatic biopsy confirmed a well-differentiated pancreatic NET (pNET). The patient subsequently developed liver metastasis and hypercalcemia with high 1,25 OH vitamin D and suppressed parathyroid hormone (PTH) levels. Hypercalcemia was refractory to chemotherapy, intravenous saline fluids, diuretics, calcitonin and zoledronate. Cinacalcet administration (120 mg/day) resulted in a significant calcium reduction. Hypocalcemia was observed when sunitinib was added three months later and cinacalcet was stopped. Subsequently, the calcium and PTH levels normalized. After six months, we observed 20% shrinkage of the pancreatic tumor and necrosis of a liver metastasis. Cinacalcet is an allosteric activator of the calcium receptor agonist, and it is used for severe hypercalcemia in patients with primary (benign and malignant) hyperparathyroidism. In this patient, cinacalcet demonstrated a calcium lowering effect, normalized hypophosphatemia, and improved the clinical condition of the patient. The mechanism through which cinacalcet improved PTH-rp mediated hypercalcemia is still unclear, but studies have suggested that a potential mechanism is the activation of calcitonin secretion. Sunitinib is an oral multi-targeted tyrosine kinase inhibitor used to treat advanced pNETs. The hypocalcemic effects of sunitinib have not been previously described in a patient with pNET. Here, we report for the first time the successful combination of cinacalcet and sunitinib in the treatment of a pNET patient presenting with malignant hypercalcemia.

Diagnostic methods for detection of bone metastases

Skeletal metastases are severe complications in the course of cancer, and they indicate a worse prognosis. The use of modern imaging techniques allows rapid diagnosis of bone metastases. Properly selected diagnostic imaging (scintigraphy, positron emission tomography, whole body MRI) allows us to evaluate the number of metastatic foci in the skeletal system. Complementary imaging examinations (X-ray, computed tomography, magnetic resonance imaging) determine the extent of metastasis and its character: osteolytic, osteoblast, mixed). Hypercalcaemia is a symptom of low specificity for metastatic bone disease (a result of osteolysis); nevertheless, it is a significant complication in oncological treatment and worsens the prognosis of the patient. A biopsy is the final stage of the diagnostic process, which allows us to assess cell and tissue changes. Guided biopsies are performed under the control of musculoskeletal imaging methods (CT, MRI) and they are the most promising tools in bone metastases diagnosis. The development of guided biopsy techniques has led to the conclusion that they should be standard in diagnosing bone metastases. Liquid biopsy (LB) seems to be the most promising diagnostic method for detection of bone metastases. LB based on tumour-specific DNA mutation gives an opportunity for early detection and assessment of the molecular heterogeneity of the overall disease.

Liver-Directed Embolization for the Long-Term Control of Hypercalcemia of Malignancy in Metastatic Breast Cancer

Hypercalcemia of malignancy is a common complication of certain types of cancers. No standard therapies exist for the treatment of hypercalcemia secondary to paraneoplastic syndromes that result in the long-term control of serum calcium levels. We report a case of metastatic breast cancer with parathyroid hormone-related protein associated with hypercalcemia of malignancy that was treated with transarterial embolization of the hepatic metastatic lesions.

Hypercalcemia. Pathophysiological Aspects

The metabolic pathways that contribute to maintain serum calcium concentration in narrow physiological range include the bone remodeling process, intestinal absorption and renal tubule resorption. Dysbalance in these regulations may lead to hyper- or hypocalcemia. Hypercalcemia is a potentionally life-threatening and relatively common clinical problem, which is mostly associated with hyperparathyroidism and/or malignant diseases (90 %). Scarce causes of hypercalcemia involve renal failure, kidney transplantation, endocrinopathies, granulomatous diseases, and the long-term treatment with some pharmaceuticals (vitamin D, retinoic acid, lithium). Genetic causes of hypercalcemia involve familial hypocalciuric hypercalcemia associated with an inactivation mutation in the calcium sensing receptor gene and/or a mutation in the CYP24A1 gene. Furthermore, hypercalcemia accompanying primary hyperparathyroidism, which develops as part of multiple endocrine neoplasia (MEN1 and MEN2), is also genetically determined. In this review mechanisms of hypercalcemia are discussed. The objective of this article is a review of hypercalcemia obtained from a Medline bibliographic search.

Hypercalcemia of malignancy and new treatment options

Hypercalcemia of malignancy affects up to one in five cancer patients during the course of their disease. It is associated with both liquid malignancies, commonly multiple myeloma, leukemia, and non-Hodgkins lymphoma and solid cancers, particularly breast and renal carcinomas as well as squamous cell carcinomas of any organ. The clinical manifestations of hypercalcemia are generally constitutional in nature and not specific to the inciting malignancy. Such physical manifestations can range from malaise to lethargy and confusion. Constipation and anorexia are common. Acute kidney injury is likely the most frequently encountered manifestation of end organ damage. Symptomatology is closely linked to both the absolute elevation of serum calcium levels and the rapidity of calcium rise. The majority of cases are humoral in etiology and related to parathyroid hormone-related protein (PTHrP). Approximately 20% of cases are the result of direct bone metastasis with extra-renal 1,25-dihydroxyvitamin D (calcitriol) and ectopic parathyroid hormone production likely accounting for less than 1% of cases. The diagnosis of hypercalcemia of malignancy is confirmed either by an elevated PTHrP or by an evidence of bone metastasis in the appropriate clinical setting. Treatment is predicated on the patient’s symptoms and absolute serum calcium level. Interventions are aimed at lowering the serum calcium concentration by inhibiting bone resorption and increasing urinary calcium excretion, the former accomplished via bisphosphonate therapy and the latter with aggressive hydration. Novel therapies for refractory disease include denosumab, a monoclonal antibody against the receptor activator of nuclear factor κB ligand, and the calcimimetic cinacalcet. Finally, anti-PTHrP antibodies have been successfully deployed in animal models of disease. Despite the efficacy of the above therapies, hypercalcemia of malignancy portends an ominous prognosis, indicating advanced and often refractory cancer with survival on the order of months.

[Esophageal Cancer Initially Presenting as Severe Paraneoplastic Hypercalcemia Requiring Hemodialysis]

Paraneoplastic hypercalcemia without bone metastasis occurs rarely in esophageal cancer. A 75-year-old man was admitted for general weakness and lethargy. Laboratory data showed high serum calcium level (corrected calcium 14.6 mg/dL), low parathyroid hormone level (3.3 pg/mL) and high parathyroid hormone-related peptide level (3.5 pmol/L). Esophagogastroscopy showed a malignant tumor in the esophagus. Histology showed moderately differentiated squamous cell carcinoma. Bone scan showed no evidence of bone metastasis. Since the patient's calcium levels remained high and mental state did not show improvement despite intravenous fluid therapy, diuretics and intravenous bisphosphonate, hemodialysis was started. After hemodialysis treatment, the serum calcium level subsequently normalized and his mental status improved. Herein, we report a rare case of paraneoplastic hypercalcemia in a patient with esophageal cancer.

Rare association between penile squamous cell carcinoma and parathyroid related peptide (PTH-rP) secretion

We report on a rare case of an adult with severe hypercalcemia secondary to the ectopic secretion of parathyroid-related peptide (PTH-rP) from a penile squamous cell cancer (PC). A patient of 47 years old was admitted with warty lesions and areas of ulceration covered by purulent material in a large area of the groin, scrotum and penis. Laboratory tests revealed severe hypercalcemia and elevation of PTH-rP; the biopsy reported PC. Hypercalcemia was successfully treated with zoledronic acid, however, the tumor displayed aggressive behavior, which resulted in a poor prognosis for the patient.

Case report: Severe hypercalcemia mimicking ST-segment elevation myocardial infarction

The identification of ST-segment elevation on the electrocardiogram is an integral part of decision making in patients who present with suspected ischemia. Unfortunately, ST-segment elevation is nonspecific and may be caused by noncardiac causes such as electrolyte abnormalities. We present a case of ST-segment elevation secondary to hypercalcemia in a patient with metastatic cancer.