Diagnosis and management of hyponatremia in cancer patients

Electrolytes and Nutritional Element Assessment among Iraqi Cancer Patients Receiving Chemotherapy

INTRODUCTION: Cancer may lead to abnormalities in electrolyte levels and acid-base disturbances in affected patients that could be induced by the tumor itself or by chemotherapy treatment. Thus, early detection is vital to improve short-term outcome and quality of life. AIM: This study aims to assess the electrolyte and protein changes in cancer patients on chemotherapy. MATERIALS AND METHODS: A cohort study was carried out on 100 newly diagnosed patients with cancer in Al-Amal National Radiation Oncology Hospital in Baghdad, Iraq, during the period from January 2019 to July 2019. An assessment of the studied samples was conducted as a baseline measure before receiving chemotherapy and after the third cycle of that treatment. Quantitative parameters included measurements of serum magnesium, calcium, sodium, chloride, potassium, zinc, Hb1Ac, total protein, and ferritin. Data analysis was carried out using Student’s t-test for variable levels. Level of significance of ≤0.05 was considered as significant. RESULTS: The studied sample comprised 77 females (77%) and 23 males (23%). There were significant decreases in the levels of magnesium and zinc while no significant changes were noted in the levels of other electrolytes. On the other hand, there was a significant decrease in the level of proteins and a significant rise in HBA1c and ferritin. CONCLUSION: Cancer patients on chemotherapy regimens suffer from major changes in the levels of vitamins, elements, and neurotransmitter that affect their lifestyle, survival, and prognosis. Frequent regular monitoring of such changes is required to harvest a positive impact on the lifestyle of cancer patients lifestyle and their outcome.

Hyponatremia in lung cancer: Incidence and prognostic value in a Danish population-based cohort study

OBJECTIVES

Hyponatremia is a common electrolyte disorder in lung cancer patients, especially in patients with small-cell lung cancer (SCLC). It has been proposed as a prognostic indicator of higher mortality; however, data have been conflicting. Here, we determine the incidence and prognostic impact of pretreatment hyponatremia in a large Danish registry-based cohort of lung cancer patients.

MATERIAL AND METHODS

Data on lung cancer patients diagnosed from January 2009 to June 2018 in The Central Denmark Region were extracted from the Danish Lung Cancer Registry and combined with data on the pretreatment sodium level extracted from the clinical laboratory information system. Hyponatremia was defined as a sodium level <135 mmol/l. Cox proportional hazard models assessed the prognostic value of hyponatremia on overall survival (OS) in patients with non-small cell lung cancer (NSCLC) and patients with SCLC.

RESULTS

A total of 6995 patients with NSCLC and 1171 with SCLC were included. The hyponatremia incidence was 16 % among patients with NSCLC and 26 % among patients with SCLC. Hyponatremia was associated with an inferior OS in patients with NSCLC (<135 mmol/l: median 0.46 years (95 % CI: 0.41-0.51) vs. ≥ 135 mmol/l: median 1.05 years (95 % CI: 1.00-1.11)), p < 0.001; adjusted hazard ratio (HR) = 1.45 (95 % CI: 1.34-1.56)) as well as in patients with SCLC in (<135 mmol/l: median 0.67 year (95 % CI: 0.58-0.73) vs. ≥ 135 mmol/l: median 0.73 years (95 % CI: 0.67-0.78); p = 0.0035; adjusted HR = 1.21 (95 % CI: 1.04-1.41)).

CONCLUSION

The incidence of pretreatment hyponatremia is high in patients with SCLC as well as with NSCLC. Hyponatremia seems to be an independent predictor of inferior survival in lung cancer patients, especially in patients with NSCLC.

Adherence to the Sociedad Española de Oncología Médica (SEOM) Algorithm for the Treatment of Hyponatremia in Oncology Patients in Spain: The ALGA Study

INTRODUCTION

The ALGA study explored adherence of Spanish treatment centers to the Sociedad Española de Oncología Médica (SEOM) treatment algorithm for oncology patients with hyponatremia that requires treatment as the main cause of hospitalization, and evaluated the impact of adherence to this algorithm on patient outcomes.

METHODS

This retrospective study recruited patients aged at least 18 years with cancer, treated for at least one episode of hyponatremia secondary to the syndrome of inappropriate antidiuretic hormone secretion (SIADH). The primary outcome was the proportion of patients whose treatment adhered to the SEOM algorithm, evaluated using a pre-defined decision tree. Secondary outcomes included length of hospitalization, and time to serum sodium level improvement. Perceived center adherence to the SEOM algorithm was also assessed.

RESULTS

Seventy patients from four treatment centers were included. Twenty (28.6%; 95% confidence interval [CI] 18.0, 39.2) patients on hyponatremia treatment adhered to the SEOM algorithm, with a perceived adherence of 51.0-75.0%. Algorithm adherence in candidates for chemotherapy was 36.4% (n = 8) versus 25.0% (n = 12) for non-candidates for chemotherapy. Median time to serum sodium level improvement in patients managed adherently was 80.5 h (95% CI 38.3, 331.4) versus 134.6 h (33.2, 444.9) in patients managed non-adherently. Median time to hospital discharge was 16.5 days (95% CI 8.0, 27.0) in patients managed adherently versus 9.5 days (7.0, 22.0) in patients managed non-adherently.

CONCLUSION

In Spanish centers, the SEOM algorithm was adhered to in less than one-third of patients, in contrast to higher levels of perceived adherence. This requires further investigation; however, algorithm use could require further clarification, especially in non-candidates for chemotherapy.

Onconephrology: The intersections between the kidney and cancer

Onconephrology is a new subspecialty of nephrology that recognizes the important intersections of kidney disease with cancer. This intersection takes many forms and includes drug-induced nephrotoxicity, electrolyte disorders, paraneoplastic glomerulonephritis, and the interactions of chronic kidney disease with cancer. Data clearly demonstrate that, when patients with cancer develop acute or chronic kidney disease, outcomes are inferior, and the promise of curative therapeutic regimens is lessened. This highlights the imperative for collaborative care between oncologists and nephrologists in recognizing and treating kidney disease in patients with cancer. In response to this need, specific training programs in onconephrology as well as dedicated onconephrology clinics have appeared. This comprehensive review covers many of the critical topics in onconephrology, with a focus on acute kidney injury, chronic kidney disease, drug-induced nephrotoxicity, kidney disease in stem cell transplantation, and electrolyte disorders in patients with cancer.

A narrative review of progress in diagnosis and treatment of small cell lung cancer patients with hyponatremia

Small cell lung cancer (SCLC) is one of the malignant cancers of lung tumors, and hyponatremia, defined as serum sodium concentration (Na⁺) lower than 135 mmol/L, is the most common complication of solid tumors, with an incidence of up to 18.9% and a negative impact on quality of life in SCLC. As a prognostic index of SCLC, timely monitoring and correcting of hyponatremia is of great clinical significance for prolonging the survival period of patients. In the explore of new drugs for small cell lung cancer, it is necessary to include hyponatremia as an evaluation index in clinical studies. As the occurrence of hyponatremia is sometimes unavoidable owing to SCLC specific neurological characteristics, early monitoring to detect the presence of hyponatremia and timely correction are helpful to improve the prognosis of patients. There are many predisposing factors for hyponatremia, including heterotopia of antidiuretic hormone (ADH), use of platinum-based chemotherapy drugs, and intracranial metastasis, among others. Patients with small cell lung cancer are usually asymptomatic in the early stage, while it is of great significance to find a suitable clinical index to judge whether it is a malignant inducement or not. In the clinical setting, due to different electrolyte levels and therapeutic scheduling for the primary disease, an individualized plan is often made, mainly comprising water restriction, infusion, and medications. This review includes related clinical studies and describes the common symptoms and predisposing factors of hyponatremia in patients with SCLC, and their impact on quality of life and prognosis.

Management of nephrotoxicity of chemotherapy and targeted agents: 2020

Nephrotoxic effects of certain chemotherapeutic agents such as cisplatin and ifosfamide has been well documented and these effects are carefully managed by oncologists during their usage. The introduction of targeted agents has added a new challenge to cancer management as their nephrotoxic effects and associated management is in the process of being adopted by oncologists. This work is a compilation of side effects on the renal system due to various chemotherapeutic, immunotherapeutic and targeted agents followed by their recommended management.

Perspectives From an Onconephrology Interest Group: Conference Report

INTRODUCTION AND OBJECTIVE

Onconephrology is a new and evolving field that deals with kidney complications in patients with cancer as well as the management of cancer in patients with preexisting kidney disease. With increasing numbers of patients with cancer with kidney-related complications, the field has garnered increased attention. Thus, an annual Greater Toronto Area Onconephrology Interest Group symposium was held in May 2019. The objective of the meeting was to demonstrate the junctures between oncology and nephrology by highlighting recent data regarding (1) kidney impairment in solid organ malignancies, (2) management and treatment of kidney cancer, (3) kidney impairment in hematologic malignancies, (4) malignancy and kidney transplantation, and (5) hyponatremia in patients with cancer.

METHODS AND SOURCES OF INFORMATION

Through a structured presentation, the group explored key topics discussed at a Kidney Disease Improving Global Outcomes (KDIGO) Controversies Conference on Onconephrology. Expert opinions, clinical trial findings, and publication summaries were used to illustrate patient and treatment-related considerations in onconephrology.

KEY FINDINGS

Kidney complications in patients with cancer are a central theme in onconephrology. An estimated 12% to 25% of patients with solid organ malignancies have chronic kidney disease (CKD), although in certain cancers, the prevalence of CKD is higher. Kidney impairment is also a common complication of some hematologic malignancies. The incidence of renal failure in patients with multiple myeloma is estimated at 18% to 56% and light chain cast nephropathy is seen in approximately 30% of these patients. In addition, there appears to be a bidirectional relationship between kidney cancer and CKD, with some data sets suggesting the risk increases as kidney function declines. Cancer is also of concern in patients with preexisting kidney disease. Kidney transplant recipients have a greater risk of cancer and a higher risk of cancer-related mortality. Kidney complications have also been associated with novel cancer therapies, such as immune checkpoint inhibitors and chimeric antigen receptor (CAR) T-cell therapy. An estimated 2% to 4% of patients initiating an immune checkpoint inhibitor may develop nephrotoxicity, whereas up to 40% of patients on CAR T-cell therapy experience cytokine release syndrome (CRS). Tumor lysis syndrome and electrolyte abnormalities, such as hyponatremia, have also been reported with CAR T-cell therapy. While the incidence and prevalence of hyponatremia vary depending on the cancer type and serum sodium cutoff point, hyponatremia may be seen in up to 46% of patients hospitalized in cancer centers.

CONCLUSIONS

Onconephrology is a developing field and the themes arising from this meeting indicate a need for greater collaboration between oncologists and nephrologists. Educational symposia and onconephrology fellowship programs may allow for improved cancer care for patients with kidney disease.

The Significance of Preoperative Serum Sodium and Hemoglobin in Outcomes of Upper Tract Urothelial Carcinoma: Multi-Center Analysis Between China and the United States

Purpose

To analyze the effect of preoperative serum sodium and hemoglobin on oncologic outcomes in upper tract urothelial carcinoma (UTUC) based on a multi-center cohort from China and the United States (U.S.).

Methods

We retrospectively reviewed the records of 775 patients with UTUC treated surgically at tertiary care medical facilities in China or the US from 1998 to 2015. We analyzed associations of preoperative serum sodium and hemoglobin with clinicopathological characteristics, overall survival (OS), cancer-specific survival (CSS) and intravesical recurrence free survival (IVRFS).

Results

The US patients had comparatively lower serum sodium and similar hemoglobin at baseline. Preoperative low serum sodium value was associated with tumor multifocality, lymph node metastasis (LNM) and lymphovascular invasion (LVI); preoperative anemia was associated with advanced age, tumor multifocality, high tumor grade and LVI. Preoperative low serum sodium was an independent predictor of worse OS in the entire cohort; preoperative anemia was an independent predictor of worse OS and CSS in the US cohort alone, Chinese cohort alone and the combined cohort. We developed a predictive nomogram for OS which exhibited better prognostic value when it included the values of sodium and anemia, and successfully validated it in different cohorts.

Conclusion

Preoperative low serum sodium and anemia could be informative in predicting worse pathologic and survival outcomes in different UTUC patient ethnic groups.

Anticancer Medications and Sodium Dysmetabolism

Therapeutic advances have revolutionised cancer treatment over the last two decades, but despite improved survival and outcomes, adverse effects to anticancer therapy such as dyselectrolytaemias do occur and need to be managed appropriately. This review explores essential aspects of sodium homeostasis in cancer with a focus on alterations arising from anticancer medications. Sodium and water balance are tightly regulated by close interplay of stimuli arising from hypothalamic osmoreceptors, arterial and atrial baroreceptors and the renal juxtaglomerular apparatus. This delicate balance can be disrupted by cancer itself, as well as the medications used to treat it. Some of the conventional chemotherapeutics, such as alkylating agents and platinum-based drugs, can cause hyponatraemia and, on rare occasions, hypernatraemia. Other conventional agents such as vinca alkaloids, as well as newer targeted cancer therapies including small molecule inhibitors and monoclonal antibodies, can cause hyponatraemia, usually as a result of inappropriate antidiuretic hormone secretion. Hyponatraemia can also sometimes occur secondarily to drug-induced hypocortisolism or salt-wasting syndromes. Another atypical but distinct mechanism for hyponatraemia is via pituitary dysfunction induced by immune checkpoint inhibitors. Hypernatraemia is uncommon and occasionally ensues as a result of drug-induced nephrogenic diabetes insipidus. Identification of the aetiology and appropriate management of these conditions, in addition to averting treatment-related problems, can be lifesaving in critical situations.

Clinical Characteristics and Analysis of Lung Cancer- Associated Acute Ischemic Stroke

INTRODUCTION

The incidence of lung cancer and acute ischemic stroke remains high in recent years, both of which occur mostly in people over 60 years old. In the present study, we aimed to further clarify the pathogenesis of lung cancer-associated acute ischemic stroke (LCA-AIS) by comparing and analyzing clinical characteristics of stroke patients with or without lung cancer.

METHODS

A total of 51 patients with lung cancer were selected as the case group (LCSG), and 78 patients without cancer history were adopted as the control group (SG). The data collected in this study included sex, age, traditional cerebrovascular disease risk factors (TCDRFs), blood test index, imaging findings, etiological typing, and prognosis evaluation. SPSS21.0 software was used for statistical analysis. Normally distributed data were analyzed by t-test, and count data were analyzed by chi-square test or exact probability method. P < 0.05 was considered statistically significant.

RESULTS

In the case group, the levels of plasma D-dimer, fibrinogen degradation products (FDPs) and NIHSS, as well as the mRS score and mortality of patients, were higher, while the levels of RBC, Hb and Hcy were lower compared with the control group. Imaging findings showed that multivessel involvement was more common in the case group, and the infarcts were more likely to be multiple and involved in both the anterior and posterior circulations. The TOAST classification of LCSG was dominated by stroke of undetermined etiology (SUE) and stroke of other determined etiology (SOE). Statistical analysis showed that the patients were more likely to suffer from acute ischemic stroke within 1 year after the diagnosis of lung cancer (41 cases, 80.39%).

CONCLUSIONS

Hypercoagulability and acute multiple brain infarcts were more common in patients with LCA-AIS, and hypoproteinemia and hyponatremia were more likely to occur in these patients, leading to worse prognosis. Patients were most likely to have a stroke within 1 year after the diagnosis of lung cancer.

Tolvaptan treatment in hyponatremia due to the syndrome of inappropriate secretion of antidiuretic hormone (SIADH): effects on survival in patients with cancer

PURPOSE

To investigate the clinical outcomes of patients with hyponatremia who received supportive treatment or tolvaptan plus supportive treatment and the effects of treatment and other variables on overall survival METHODS: This study included oncology patients who were hospitalized at two oncology centers between January 1, 2016 and December 31, 2019 for hyponatremia (sodium levels < 135 mEq/L) and who received tolvaptan plus supportive treatment (n = 22) or supportive treatment only (n = 42).

RESULTS

The median age of all the patients was 59 years (range 26-85) and 64.1% of the patients were male. There was no statistically significant difference between patients in the tolvaptan plus supportive treatment (TpST) group and the supportive treatment only (ST) group in terms of gender and age (p > 0.05). In the TpST group, recovery days of the hyponatremia after treatment and the length of hospital stay was shorter and hyponatremia symptoms and hospital complications were less frequent compared to the ST group (p < 0.05). There was no significant difference between the TpST group and the ST group in terms of overall survival (OS). OS was shorter in men who were non-responders to hyponatremia treatment and had recurrent hyponatremia. Multivariable analysis showed that normal sodium levels after treatment decreased the risk of death.

CONCLUSION

In the treatment of hyponatremia in cancer patients, TpST was found to have more positive effects on blood sodium levels, length of hospital stay, hospital complications, and hyponatremia symptoms compared to ST. A decreased risk of death was observed in patients with normal sodium levels after treatment.

Syndrome of Inappropriate Antidiuretic Hormone Secretion (SIADH): Optimal Management

Hyponatremia, defined as serum sodium concentration <135 mEq/l, is the most common electrolyte balance disorder in clinical practice. Many causes are listed, but syndrome of inappropriate antidiuretic hormone secretion (SIADH) is certainly the most relevant, mainly in oncological and hospitalized patients. In this review, the pathophysiological and clinical aspects are described in detail. Patients' extensive medical history and structured physical and biochemical tests are considered the milestones marking the way of the SIADH management as to provide early detection and proper correction. We focused our attention on the poor prognostic role and negative effect on patient's quality of life of SIADH-induced hyponatremia in both malignant and non-malignant settings, stressing how optimal management of this electrolyte imbalance can result in improved outcomes and lower health costs.

Peripherally administered cisplatin activates a parvocellular neuronal subtype expressing arginine vasopressin and enhanced green fluorescent protein in the paraventricular nucleus of a transgenic rat

Cisplatin is one of the most potent anti-cancer drugs, though several side effects can induce stress responses such as activation of the hypothalamic-pituitary adrenal (HPA) axis. Arginine vasopressin (AVP) and corticotrophin-releasing hormone (CRH) expressed in the parvocellular division of the paraventricular nucleus (pPVN) play an important role in the stress-induced activation of the HPA axis. We aimed to evaluate whether intraperitoneal (i.p.) administration of cisplatin could activate parvocellular neurons in the pPVN, using a transgenic rat model that expresses the fusion gene of AVP and enhanced green fluorescent protein (eGFP). Along with the induction of FosB, a marker of neuronal activation, i.p. administration of cisplatin significantly increased eGFP fluorescent intensities in the pPVN. In situ hybridization histochemistry revealed that AVP-eGFP and CRH mRNAs in the pPVN were increased significantly in cisplatin-treated rats. These results suggest that cisplatin administration increases neuronal activation and upregulates AVP and CRH expression in the pPVN.

Electrolyte disorders in advanced non-small cell lung cancer patients treated with immune check-point inhibitors: A systematic review and meta-analysis

BACKGROUND

Aim of this meta-analysis was to determine the relative risk (RR) of electrolyte disorders (EDs) in advanced non-small cell lung cancer (aNSCLC) patients treated with immune check-point inhibitors (ICIs).

METHODS

We searched for phase II/III randomized controlled trials (RCTs) comparing ICIs (alone or combined with chemotherapy) with standard chemotherapy in aNSCLC. Summary incidence and RR were calculated.

RESULTS

Six RCTs with data on all-grade hyponatremia were identified (n = 3257). The incidence was 8.7 % in the study group and 4.9 % in the control group (RR 1.78, 95 %CI 1.12-2.80). Looking at all-grade hypokalemia, 7 RCTs were included (n = 4119). Incidence was 10.4 % in ICIs-treated patients and 5.9 % in the control arms (RR 1.62, 95 % CI 1.30-2.02).

CONCLUSIONS

Treatment with ICIs in aNSCLC is associated with a significant increased risk of hyponatremia and hypokalemia compared to chemotherapy. Monitoring of electrolyte levels should be emphasized in this setting.

The Role of Hyponatraemia Before Surgery in Patients With Radical Resected Pancreatic Cancer

OBJECTIVES

Hyponatraemia represents a negative prognostic factor in patients with cancer. The aim of this study was to assess, for the first time, the role of hyponatraemia in patients undergoing radical surgery for pancreatic ductal adenocarcinoma.

METHODS

A total of 89 patients with stage I-III pancreatic ductal adenocarcinoma underwent radical surgery between November 2012 and October 2014. Relapse-free survival (RFS) and disease-specific survival (DSS) were estimated using Kaplan-Meier method. A Cox regression model was carried out for univariate and multivariate analyses. Fisher exact test was used to estimate correlation between variables.

RESULTS

In total, 12 patients (14%) presented with hyponatraemia at diagnosis. The median DSS was 20 months in patients with hyponatraemia and not reached in patients with eunatraemia (P < .1073), while a statistical significant difference was observed in terms of median RFS (10 months vs 17 months, respectively; P = .0233). Considering clinical features (hyponatraemia, smoke and alcoholic habit, diabetes, pain, and jaundice), patients with 4 or more of these factors had a worse prognosis (mDSS: 30 months vs not reached; hazard ratio [HR]: 0.40, 95% confidence interval [CI] = 0.16-0.80; P = .0120).

CONCLUSIONS

The presence of hyponatraemia and its prompt correction at the diagnosis time should be considered for the correct management of patients with pancreatic carcinoma.

A case of ALK-rearranged lung adenocarcinoma associated with syndrome of inappropriate antidiuretic hormone

A 60-year-old man with a history of smoking was transferred to our hospital for consciousness disorder. A diagnosis of ALK-rearranged lung adenocarcinoma associated with a paraneoplastic electrolytic disorder was made following a cutaneous needle biopsy. Both the primary lung lesion and multiple metastases shrunk and his electrolytic disorder resolved after the introduction of a first-line molecular-targeted drug chemotherapy with crizotinib. We herein report a case of ALK-rearranged lung adenocarcinoma accompanied by SIADH, successfully treated with crizotinib.

Hyponatremia is a Predictor of Clinical Outcome for Resected Biliary Tract Cancers: A Retrospective Single-Center Study

INTRODUCTION

Biliary tract cancers (BTC) include both gallbladder cancer and cholangiocarcinoma, both of which have a poor prognosis. The aim of our study was to evaluate the main clinical prognostic factors in this setting and to assess their impact on overall survival (OS).

METHODS

We retrospectively analyzed data collected on 64 patients with BTC who underwent surgery with radical intent at our institution. OS was estimated using the Kaplan-Meier method. The Cox regression model was used to perform univariate and multivariate analyses.

RESULTS

Preoperative hyponatremia was found to be an independent prognostic factor that correlated negatively with prognosis, with hyponatremic patients having a poor OS compared to the group of patients with normal serum sodium levels (9.44 vs. 15.47 months; p = 0.0215). In addition, high preoperative values for carbohydrate antigen 19-9 (Ca19.9), a tumor marker for some gastrointestinal cancers, and lactate dehydrogenase (LDH) were found to be prognostic factors for a significant reduction in OS (Ca19-9: 7.14 vs. 24.22 months, p  = 0.0088; LDH: 1.70 vs. 15.47 months, p = 0.0384).

CONCLUSION

Identification of these prognostic factors may support strategies to identify, in clinical practice, those subgroups of patients with a favorable or unfavorable prognosis before surgical treatment and, therefore, to guide therapeutic choices. In particular, to our knowledge, this is the first report of the prognostic role of serum sodium level in BTC. Early detection and careful monitoring of hyponatremia and supportive therapy can help to improve the treatment and prognosis of BTC.

Electrolyte Disorders Induced by Antineoplastic Drugs

The use of antineoplastic drugs has a central role in treatment of patients affected by cancer but is often associated with numerous electrolyte derangements which, in many cases, could represent life-threatening conditions. In fact, while several anti-cancer agents can interfere with kidney function leading to acute kidney injury, proteinuria, and hypertension, in many cases alterations of electrolyte tubular handling and water balance occur. This review summarizes the mechanisms underlying the disturbances of sodium, potassium, magnesium, calcium, and phosphate metabolism during anti-cancer treatment. Platinum compounds are associated with sodium, potassium, and magnesium derangements while alkylating agents and Vinca alkaloids with hyponatremia due to syndrome of inappropriate antidiuretic hormone secretion (SIADH). Novel anti-neoplastic agents, such as targeted therapies (monoclonal antibodies, tyrosine kinase inhibitors, immunomodulators, mammalian target of rapamycin), can induce SIADH-related hyponatremia and, less frequently, urinary sodium loss. The blockade of epidermal growth factor receptor (EGFR) by anti-EGFR antibodies can result in clinically significant magnesium and potassium losses. Finally, the tumor lysis syndrome is associated with hyperphosphatemia, hypocalcemia and hyperkalemia, all of which represent serious complications of chemotherapy. Thus, clinicians should be aware of these side effects of antineoplastic drugs, in order to set out preventive measures and start appropriate treatments.

Risk Factors for Severe Hyponatremia Related to Cisplatin: A Retrospective Case-Control Study

Onset of severe hyponatremia following cisplatin (CDDP) administration has been previously reported. However, the risk factors associated with hyponatremia still remain unclear. We conducted a retrospective, single-center, case-control study to identify independent risk factors of severe hyponatremia in patients with various types of cancers. Adult patients who received intravenous CDDP administration between January 2012 and December 2017 met the inclusion criteria. The investigators recorded patients' demographics and clinical information retrospectively, and assessed the lowest serum sodium level within 21 d of the first CDDP administration. Risk factors for grade ≥3 hyponatremia were examined via a logistic regression analysis. Among a total of 472 patients, fifty patients (10.6%) developed grade ≥3 hyponatremia. Univariate analysis revealed that age (≥65 years), presence of small cell lung or esophageal cancer, and lower sodium concentrations in the serum (<138 mEq/L) were significantly associated with grade 3 and 4 hyponatremia. Additionally, multivariable logistic regression analysis showed that the presence of small cell lung cancer (adjusted odds ratio, 3.26; 95% confidence interval (CI), 1.07-10.00) and lower sodium concentrations in the serum (<138 mEq/L) (adjusted odds ratio, 6.18; 95%CI, 3.21-11.90) were independent risk factors of grade 3 and 4 hyponatremia. Thus, serum sodium concentrations in patients with these risk factors should be closely monitored after CDDP administration.

Hyponatremia in patients with cancer

PURPOSE OF REVIEW

Hyponatremia is seen commonly in patients with cancer and is associated with increased mortality and morbidity. Understanding the proper diagnosis and therapy of cancer-associated hyponatremia is critical to ensure improved outcomes.

RECENT FINDINGS

The most common cancers associated with hyponatremia are the various forms of lung cancer with incidences approaching 25-45%. The most common causes of hyponatremia in cancer patients are the syndrome of inappropriate antidiuretic hormone secretion [syndrome of inappropriate antidiuretic hormone (ADH)] and volume depletion. Proper diagnosis rests on clinical information supplemented by laboratory studies and is critical to ensure appropriate therapy. In recent years, the development of drugs that specifically antagonize the vasopressin type 2 receptor in the distal tubule have offered targeted and highly effective therapies for syndrome of inappropriate ADH.

SUMMARY

Hyponatremia in cancer patients generally indicates advanced or severe disease but proper therapy that targets the underlying process can improve outcomes.

Hyponatremia and Cancer Progression: Possible Association with Sodium-Transporting Proteins

Hyponatremia, the phenomenon of serum sodium level falling below 135 mmol/L, is seen frequently in cancer patients and has been correlated with poor prognosis. Hyponatremia has classically been attributed to the "syndrome of inappropriate antidiuretic hormone secretion," leading to prolonged fluid retention. However, this is unlikely to be the only mechanism. In this study, we advance the hypothesis that upregulation of various sodium-transporting proteins during the cancer process makes a significant contribution to the pathophysiology of cancer-associated hyponatremia. Such sodium-transporting proteins include voltage-gated sodium channels, especially its hypoxia-promoted persistent current, epithelial sodium channels, and transient receptor potential channels. Thus, hyponatremia follows cancer, whereby drop in blood serum level occurs as a result of uptake of sodium from extracellular fluid by cancer cells. Indeed, the sodium content of cancer cells/tissues is higher than normal. In turn, the rise in the intracellular sodium concentration brings about a range of cellular effects, including extracellular acidification that promotes invasiveness and thus leads to poor prognosis. This perspective offers novel therapies for cancer and the associated hyponatremia.

Higher incidence of syndrome of inappropriate antidiuretic hormone secretion during induction chemotherapy of acute lymphoblastic leukemia in indian children

BACKGROUND

Syndrome of inappropriate antidiuretic hormone secretion (SIADH) is a well-known adverse effect of vincristine (VCR). Literature suggests that Asians are predisposed to develop SIADH following VCR administration. However, data regarding the occurrence of SIADH in children with malignancy are limited. This study aims to analyze the incidence, clinical picture, risk factors, management, and outcome of SIADH during induction chemotherapy for pediatric acute lymphoblastic leukemia (ALL).

MATERIALS AND METHODS

A prospective study was conducted among the 166 newly diagnosed pediatric ALL patients who were treated at a tertiary cancer center in India between January 2015 and December 2015. Patients who developed hyponatremia during induction chemotherapy were further investigated for SIADH.

RESULTS

The incidence of SIADH was 10.8% (n = 18) with a mean sodium level of 125 mEq/L (114-129 mEq/L). In the preceding 2 weeks, 72% of episodes were associated with the administration of two (n = 6) or three (n = 7) doses of VCR. One child presented with seizures. All the patients were managed with fluid restriction and only two patients required sodium correction with 3% saline. Girls older than 10 years of age showed a marginally significant correlation to develop SIADH (P-value = 0.059).

CONCLUSION

We report a higher incidence of SIADH (10.8%) in Indian children, compared to that described in the literature, during induction chemotherapy for ALL. Regular monitoring of sodium levels during this period of chemotherapy is hence essential for the timely diagnosis and appropriate management of SIADH, which in turn will avert complications, including neurological symptoms secondary to SIADH.

Effects of low extracellular sodium on proliferation and invasive activity of cancer cells in vitro

PURPOSE

Hyponatremia is the most common electrolyte disorder in hospitalized patients, and its etiopathogenesis is related to an underlying tumor in 14% of cases. Hyponatremia has been associated with a worse outcome in several pathologies, including cancer, in which the leading cause of this electrolyte alteration is the syndrome of inappropriate antidiuresis. The aim of this study was to analyze in vitro the effects of low extracellular [Na⁺] in cancer progression.

MATERIALS AND METHODS

We used a previously validated experimental model of chronic hyponatremia to characterize the effects of low extracellular [Na⁺] in different human cancer cell lines: pancreatic adenocarcinoma (PANC-1), neuroblastoma (SK-N-AS, SH-SY5Y), colorectal adenocarcinoma (HCT-8), chronic myeloid leukemia (K562).

RESULTS

Our results demonstrate a direct relationship between low [Na⁺], reduced cell adhesion and increased invasion and proliferation in all cell lines tested. Accordingly, the number of tumor colonies grown in soft agar and the expression of collagenases type IV (metalloproteinases 2 and 9) were markedly higher in cancer cells exposed to reduced extracellular [Na⁺]. Gene analysis showed an upregulation of molecular pathways involved in oxidative stress (heme oxygenase 1) and in proliferation and invasion (RhoA, ROCK-1, ROCK-2). The activation of RhoA/ROCK pathway was paralleled by a deregulation of the cytoskeleton-associated proteins, resulting in the promotion of actin cytoskeletal remodeling and cell invasion.

CONCLUSIONS

Overall, our data demonstrate for the first time that low [Na⁺] promotes cancer progression in vitro, thus suggesting that hyponatremia is not a simple bystander of disease severity in cancer.

Hyponatremia and hypercalcemia: a study of a large cohort of patients with lung cancer

BACKGROUND

Hyponatremia and hypercalcemia are reported to be associated with poorer prognosis in lung cancer. Our study assessed the incidence of hyponatremia and hypercalcemia in a recent large cohort of patients diagnosed with lung cancer in an academic institution and correlated incidence with patient and tumour parameters.

METHODS

All patients presented at our regional lung cancer multidisciplinary team meeting between January 2011 and December 2016 were included. The incidence of hyponatremia (serum sodium ≤135 mEq/L) and hypercalcemia (serum calcium >2.62 mmol/L), including severity (mild, moderate or severe) was evaluated and stratified by tumour subtype and stage, and correlated with patient parameters.

RESULTS

A total of 624 patients (mean age, 67.4 years; 59.3% male) diagnosed with tissue-proven lung cancer were included. Hyponatremia and hypercalcemia were present in 31.6% (n=197) and 7.1% (n=44) at time of diagnosis. Hyponatremia occurred most commonly in patients with small cell lung carcinoma (SCLC) (n=42; 41.2%; P=0.001). Hypercalcemia occurred most commonly in patients with non-small cell lung carcinoma (NSCLC) squamous subtype (n=27; 12.2%; P=0.003). The incidence of hyponatremia and hypercalcemia were significantly higher in the advanced stages (P<0.041), except in SCLC where no difference in hypercalcemia incidence across the stages was observed (P=0.573). The Eastern Cooperative Oncology Group Performance Status (ECOG-PS) score was positively correlated with severity of hyponatremia at the early stage of NSCLC (Spearman correlation coefficient =0.325; P=0.003).

CONCLUSIONS

Hyponatremia is a common association in lung cancer, especially in SCLC. Hypercalcemia is an uncommon but significant association in the NSCLC squamous subtype. Hyponatremia might contribute to poorer ECOG-PS scores at the early stage of NSCLC.

Clinical Approach to Sodium Homeostasis Disorders in Children with Pituitary-Suprasellar Tumors

Children with pituitary-suprasellar tumors are at high risk of developing sodium metabolism disorders since the tumoral mass itself or surgical and medical treatment can damage AVP release circuits. Additional risk factors are represented by the use of hypotonic fluids, the young age, total parenteral nutrition, and obstructive hydrocephalus secondary to tumor pathology. The most frequent hyponatremic disorders related to AVP in these patients are the syndrome of inappropriate ADH secretion and the cerebral/renal salt wasting syndrome, while hypernatremic conditions include central diabetes insipidus (CDI) and adipsic CDI. The main challenge in the management of these patients is to promptly distinguish the AVP release disorder at the base of the sodium imbalance and treat it correctly by avoiding rapid sodium fluctuations. These disorders can coexist or follow each other in a few hours or days; therefore, careful clinical and biochemical monitoring is necessary, especially during surgery, the use of chemotherapeutic agents, or radiotherapy. This monitoring should be performed by experienced healthcare professionals and should be multidisciplinary, including pediatric endocrinologists, neurosurgeons, and oncologists since maintaining sodium homeostasis also plays a prognostic role in terms of disease survival, therapeutic response, hospitalization rate, and mortality. In this review, we analyze the management of sodium homeostasis disorders in children with pituitary-suprasellar tumors and discuss the main challenges in the diagnosis and treatment of these conditions based on literature data and over 30 years of clinical experience at our Department of Pediatric Endocrinology.

Syndrome of inappropriate anti-diuretic hormone secretion in cancer patients: results of the first multicenter Italian study

BACKGROUND

Hyponatremia in cancer patients is often caused by the syndrome of inappropriate antidiuretic hormone secretion (SIADH). The aim of this observational multicenter study was to analyze the medical and economic implications of SIADH in this setting.

METHODS

This study included 90 oncological patients from 28 Italian institutions that developed SIADH between January 2010 and September 2015. Data on clinical-pathological characteristics, anticancer therapies, hyponatremia, and related treatments were statistically analyzed.

RESULTS

The majority were lung cancer patients (73%) with metastatic disease at the onset of hyponatremia (83%). A total of 76 patients (84%) were hospitalized because of SIADH and less than half (41%) received tolvaptan for SIADH treatment. The duration of hospitalization was significantly longer in patients who did not receive tolvaptan and in those who do not reach sodium normalization during hospitalization. Patients who experienced a second episode of hyponatremia following tolvaptan dose modification/discontinuation presented a significantly lower serum sodium value at the time of hospitalization and minimum sodium value during hospitalization compared with patients who had not experienced another episode. The severity of hyponatremia, defined as minimum sodium value during hospitalization with a cut-off value of 110 mmol/l, and not obtaining sodium correction during hospitalization significantly correlated with overall survival rate.

CONCLUSIONS

Hyponatremia due to SIADH could result in longer hospitalization and in a decreased overall survival when not adequately treated, and tolvaptan represents an effective treatment with a potential effect of both improving overall survival and decreasing duration of hospitalization.

Preoperative Hyponatremia And Hypocalcemia Predict Poor Prognosis In Elderly Gastric Cancer Patients

Background

Hyponatremia and hypocalcemia are common in patients with cancer, but their prognostic impact in patients who underwent gastric cancer (GC) surgery has not been investigated. Therefore, this study aimed to determine the postoperative prognostic impact of hyponatremia and hypocalcemia in patients undergoing curative gastrectomy by age group.

Materials and methods

GC patients preoperatively diagnosed with hyponatremia or hypocalcemia who underwent elective radical gastrectomy were retrospectively evaluated. The patients were divided into the elderly group (≥60 years) and the young group (<60 years), and then further based on their sodium and calcium levels. The effect of preoperative hyponatremia or hypocalcemia on postoperative complications (PCs) by age was determined using univariate and multivariate analyses. Overall survival (OS) was compared between the two groups using log rank test and Cox proportional hazards regression.

Results

Of the 842 patients evaluated, 36 (4.3%) were categorized into the younger hyponatremia group; 64 (7.6%), the elderly hyponatremia group; 48 (5.7%), the young hypocalcemia group; and 128 (15.2%), the elderly hypocalcemia group. Hyponatremia (P=0.001) and hypocalcemia (P=0.038) were independent risk factors for PCs in the elderly group. Further, hypocalcemia (hazard ratio (HR), 0.676; P=0.037) was independently associated with shorter OS.

Conclusion

Preoperative hyponatremia and hypocalcemia predict poor outcomes in the elderly, but not in young GC patients. Further, hyponatremia and hypocalcemia in elderly GC patients should be corrected in the earliest time possible to obtain better clinical outcomes.

Low Baseline Serum Sodium Concentration Is Associated with Poor Clinical Outcomes in Metastatic Non-Small Cell Lung Cancer Patients Treated with Immunotherapy

BACKGROUND

A consistent percentage of patients with metastatic non-small cell lung cancer (NSCLC) derives no or only marginal benefit from immunotherapy (IO).

OBJECTIVE

Since serum sodium has been linked to both prognosis in NSCLC and modulation of immune cells activity, we aimed to assess the association between low baseline serum sodium concentration (≤ 135 mEq/L) and clinical outcomes of patients with metastatic NSCLC treated with IO.

PATIENTS AND METHODS

We included metastatic NSCLC patients treated with checkpoint inhibitors in our department from April 2013 to April 2018 with available baseline serum sodium concentration. Demographics, clinical and pathological characteristics were collected. Survival analyses were performed using the Kaplan-Meier method and the Cox proportional-hazards model.

RESULTS

Of 197 patients included, 26 (13%) presented low baseline serum sodium concentration. Patients in the low sodium cohort experienced a poorer disease control rate (OR 0.36; 95% CI, 0.15-0.86; Wald test P = .02), median overall survival (OS) (2.8 vs. 11.6 months; HR 3.00; 95% CI, 1.80-4.80; P < .001) and progression-free survival (PFS) (1.8 vs. 3.3 months; HR 2.60; 95% CI, 1.70-3.90; P < .001) compared to patients in the control cohort. At multivariate analyses, low baseline serum sodium concentration was independently associated with disease control and OS, but not with PFS.

CONCLUSIONS

Our study showed for the first time that low baseline serum sodium concentration is associated with impaired clinical outcomes in patients with metastatic NSCLC treated with IO. The role of serum sodium concentration in this setting warrants further pre-clinical and clinical investigation.

Weighing the prognostic role of hyponatremia in hospitalized patients with metastatic solid tumors: the HYPNOSIS study

Previous works linked low sodium concentration with mortality risk in cancer. We aimed at weighing the prognostic impact of hyponatremia in all consecutive patients with metastatic solid tumors admitted in a two-years period at our medical oncology department. Patients were included in two cohorts based on serum sodium concentration on admission. A total of 1025 patients were included, of whom 279 (27.2%) were found to be hyponatremic. The highest prevalence of hyponatremia was observed in biliary tract (51%), prostate (45%) and small-cell lung cancer (38.9%). With a median follow-up of 26.9 months, median OS was 2 months and 13.2 months for the hyponatremia versus control cohort, respectively (HR, 2.65; P < 0.001). In the multivariable model, hyponatremia was independently associated with poorer OS (HR, 1.66; P < 0.001). According to the multivariable model, a nomogram system was developed and validated in an external set of patients. We weighed over time the influence of hyponatremia on survival of patients with metastatic solid tumors and pointed out the possibility to exploit serum sodium assessment to design integrated prognostic tools. Our study also highlights the need for a deeper characterization of the biological role of extracellular sodium levels in tumor development and progression.

Syndrome of inappropriate antidiuretic hormone secretion and Leser-Trélat syndrome as uncommon paraneoplastic manifestations of renal malignancy - a geriatric experience: a case report

Background

Leser–Trélat syndrome, which manifests as eruptive multiple seborrheic keratoses, is a rare paraneoplastic sign. Hyponatremia in the elderly population is an often overlooked but potentially sinister biochemical abnormality. Cancer-related causes of hyponatremia include syndrome of inappropriate antidiuretic hormone secretion, cerebral or renal salt wasting, and adrenal dysfunction. We report a case of an elderly man who presented with both syndrome of inappropriate antidiuretic hormone secretion and Leser–Trélat syndrome, and was eventually found to have renal malignancy.

Case presentation

A 74-year-old indigenous Malaysian man with underlying chronic kidney disease presented with recurrent admissions for hyponatremia with parameters indicative of syndrome of inappropriate antidiuretic hormone secretion, constitutional symptoms, and diffuse skin lesions suggestive of multiple seborrheic keratoses. A radiological workup revealed metastatic renal cell carcinoma with evidence of metastasis to the brain, adrenal glands, bone, and lungs.

Conclusions

To the best of our knowledge, renal malignancy presenting as syndrome of inappropriate antidiuretic hormone secretion and Leser–Trélat concurrently is rare. The causes of hyponatremia in the elderly, approach to investigation, and value as a poor prognostic marker in malignancy are highlighted. We also discuss Leser–Trélat syndrome, its pathophysiology, and its possible implications on clinical practice.

Urea in cancer patients with chronic SIAD-induced hyponatremia: Old drug, new evidence

BACKGROUND

Syndrome of inappropriate antidiuresis (SIAD) is the main cause of hyponatremia in cancer patients. International guidelines indicate urea as an interesting option for chronic SIAD. Nevertheless, strong data to support its use are lacking, and its role in oncologic patients has not been described so far.

MATERIAL AND METHODS

We retrospectively analysed 36 cancer patients affected by moderate or profound SIAD-induced chronic hyponatremia, who started oral urea (initial daily dose 15 g or 30 g) without fluid restriction between July 2013 and July 2018. We analysed mean serum sodium (sNa) increase after 24 hours and percentages of patients who reached eunatremia within 14, 30 and 60 days of treatment, stratifying according to the degree of hyponatremia at diagnosis. Clinical evaluation and biochemical assessment were periodically performed.

RESULTS

Mean sNa was 123 [±4] mmol/L at baseline; after 24 hours of treatment, a mean increase of 5 [±3] mmol/L was observed. Eunatremia was reached by 55.6%, 86.1% and 91.7% patients within 14, 30 and 60 days of treatment, respectively. Trends in sNa normalization were similar in patients with moderate and profound hyponatremia at diagnosis. Rapid sNa overcorrection was avoided in all cases. Urea  was interrupted within  the first  2 months  of treatment in 10 patients, in half cases for rapid neoplastic progression and in the remaining patients for the drug taste.

CONCLUSIONS

In our study, urea was effective in correcting chronic hyponatremia among cancer patients with SIAD. Almost all patients reached eunatremia within the first month of therapy, and urea was globally well tolerated.

Outcome Definition Influences the Relationship Between Genetic Polymorphisms of ERCC1, ERCC2, SLC22A2 and Cisplatin Nephrotoxicity in Adult Testicular Cancer Patients

Although previous research identified candidate genetic polymorphisms associated with cisplatin nephrotoxicity, varying outcome definitions potentially contributed to the variability in the effect size and direction of this relationship. We selected genetic variants that have been significantly associated with cisplatin-induced nephrotoxicity in more than one published study (SLC22A2 rs316019; ERCC1 rs11615 and rs3212986; ERCC2 rs1799793 and rs13181) and performed a replication analysis to confirm associations between these genetic polymorphisms and cisplatin nephrotoxicity using various outcome definitions. We included 282 germ cell testicular cancer patients treated with cisplatin from 2009-2014, aged >17 years recruited by the Canadian Pharmacogenomics Network for Drug Safety. Nephrotoxicity was defined using four grading tools: (1) Common Terminology Criteria for Adverse Events (CTCAE) v4.03 for acute kidney injury (AKI) or CTCAE-AKI; (2) adjusted cisplatin-induced AKI; (3) elevation of serum creatinine; and (4) reduction in the estimated glomerular filtration rate (eGFR). Significant associations were only found when using the CTCAE v4.03 definition: genotype CA of the ERCC1 rs3212986 was associated with decreased risk of cisplatin nephrotoxicity (ORadj = 0.24; 95% CI:0.08-0.70; p= 0.009) compared to genotype CC. In contrast, addition of allele A at SLC22A2 rs316019 was associated with increased risk (ORadj = 4.41; 95% CI:1.96-9.88; p < 0.001) while genotype AC was associated with a higher risk of cisplatin nephrotoxicity (ORadj = 5.06; 95% CI:1.69-15.16; p= 0.004) compared to genotype CC. Our study showed that different case definitions led to variability in the genetic risk ascertainment of cisplatin nephrotoxicity. Therefore, consensus on a set of clinically relevant outcome definitions that all such studies should follow is needed.

A rare case of sorafenib-induced severe hyponatremia

Background:

Sorafenib is an anti-angiogenic tyrosine kinase inhibitor used to treat patients with renal cell cancer and advanced hepatocellular cancer. Common adverse effects of sorafenib are rash, diarrhea, nausea, and abnormal liver function test and hand-foot syndrome.

Case presentation:

Here, we present a case of a 90-year-old male who was prescribed sorafenib after being diagnosed with hepatocellular cancer. At 1 week after sorafenib initiation, he was admitted to the emergency room for an evaluation of weakness. The patient had hyponatremia, a common electrolyte abnormality seen in cancer patients. His hyponatremia improved when the sorafenib was stopped, suggesting that this was a rare case of hyponatremia induced by sorafenib.

Conclusion:

Although sorafenib is used in the treatment of hepatocellular cancer, it can cause life-threatening complication such as hyponatremia. Early identification of the cause of hyponatremia can prevent serious adverse event.

The prognostic and predictive role of hyponatremia in patients with advanced non-small cell lung cancer (NSCLC) with bone metastases

PURPOSE

Hyponatremia and bone metastasis (BMs) are known as negative prognostic factors in patients affected by metastatic non-small cell lung cancer (NSCLC). Hyponatremia is associated with higher risk of osteoporosis and bone fracture, but no data are available about the relationship between hyponatremia and bone metastasis. This study aims to analyze the prognostic impact of hyponatremia in NSCLC patients with bone metastases.

METHODS

We retrospectively collected data about advanced NSCLC patients. Survival curves were estimated using Kaplan-Meier method, and comparisons were made using chi-square test.

RESULTS

Six hundred forty-seven patients were enrolled into the study. BMs were present in 264 patients (41%) at diagnosis, while hyponatremia appeared in 237 (37%) patients during the first-line treatment. Patients without BMs had a median overall survival (mOS) of 15.9 months (95% CI 14.1-17.9) versus 11.4 months (95% CI 9.4-13.4) for patients with BMs (p = 0.001). Eunatremic patients had a better outcome (mOS 16.3 months, 95% CI 14.6-18.0 vs 10.3 months, 95% I 7.6-12.8, p = 0.003). Considering the two variables, patients with BMs and hyponatremia had a mOS of 10.1 months (95% CI 4.3-15.9), patients with hyponatremia without BMs 11.9 months (95% CI 11.4-12.4), while mOS was 13.1 months (95% CI 12.0-14.2) for eunatremic patients with BMs versus 17.1 months (95% CI 15.2-19.1) in eunatremic patients without BMs (p = 0.0020). Hyponatremic patients developed metachronous BMs significantly earlier (3.73 vs 5.76 months, p = 0.0187).

CONCLUSIONS

Our study showed that hyponatremia is an important prognostic factor and it should be necessarily considered to enhance the management of NSCLC patients with BMs.

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.

Prognostic value of preoperative hyponatremia in patients with epithelial ovarian cancer

Hyponatremia is an emerging issue in cancer patients. However, few studies have explored the prognostic value of preoperative hyponatremia in epithelial ovarian cancer (EOC) patients. We conducted a retrospective study of women diagnosed with EOC at Shengjing Hospital from 2011 to 2015. Preoperative serum sodium levels were measured and classified as normal (136-145 mmol/L) or hyponatremic (≤135 mmol/L) according to the average/most recent measurements of this biomarker. Multivariable Cox proportional hazard regression models were applied to determine the adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) for the association of preoperative hyponatremia with progression-free survival (PFS) and overall survival (OS). We identified 607 EOC patients meeting the inclusion criteria with a median age of 51 years (inter-quartile range: 47-59 years). The median follow-up duration was 3.1 years (inter-quartile range: 2.2-4.2). The recurrence and mortality rates were 56.8% (345/607) and 38.4% (233/607), respectively. Among the patients, 81 (13.3%) were observed as hyponatremic. Preoperative hyponatremia was associated with poorer PFS (HR=1.51; 95%CI=1.07-2.15) as well as OS (HR=1.47; 95%CI=1.03-2.11) after adjusting for potential confounders. Notably, results were in line with the main findings only when using the most recent serum sodium levels before treatment, with corresponding HRs of 1.58 (95%CI=1.12-2.23) for PFS and 1.45 (95%CI=1.02-2.07) for OS. Preoperative hyponatremia is an independent prognostic factor of EOC. Further studies are warranted to confirm our findings as well as to determine whether correction of preoperative hyponatremia may alter clinical outcomes in these patients.

Tolvaptan corrects hyponatremia and relieves the burden of fluid/dietary restriction and hospitalization in hyponatremic patients with terminal lung cancer: a report of two cases

Case 1: A 45-year-old man, admitted for symptomatic hyponatremia, was diagnosed with advanced small-cell lung cancer and severe hyponatremia due to the syndrome of inappropriate secretion of antidiuretic hormone. In addition to chemotherapy, the patient was treated with increased dietary salt intake (15 g/day), fluid restriction of 500 mL/day, and amino acid supplementation to maintain a urea load of 31 g/day. Due to the difficulty in changing his habit of drinking 2-3 L/day after discharge, tolvaptan was started. This resulted in correction of hyponatremia, which facilitated earlier discharge and improved his quality of life by eliminating the need for dietary restriction.Case 2: An 88-year-old man with asymptomatic hyponatremia was admitted for assessment of pleural effusion. He was diagnosed with small-cell lung cancer with mild hyponatremia due to the syndrome of inappropriate secretion of antidiuretic hormone. He was treated with best supportive care and dietary modification (salt intake of 15 g/day and fluid restriction of 400 mL/day). He found it difficult to comply with the dietary changes, and prolonged hospitalization was required for hyponatremia correction. Therefore, tolvaptan was initiated, which corrected his hyponatremia, and the patient was discharged.In summary, tolvaptan results in stable correction of hyponatremia in patients with terminal small-cell lung cancer complicated by the syndrome of inappropriate secretion of antidiuretic hormone. Furthermore, it improves the quality of life of these patients by relieving the burden of strict dietary modifications and prolonged hospitalization.

Hyponatremia in patients with esophageal cancer treated with chemotherapy including cisplatin

BACKGROUND

Little is known about hyponatremia in patients with esophageal cancer treated with cisplatin-based chemotherapy. The aim of this study was to analyze the risk factors for hyponatremia and its effect on outcomes in patients with esophageal cancer treated with chemotherapy including cisplatin.

METHODS

We retrospectively analyzed the records of 137 patients with esophageal cancer who received chemotherapy including cisplatin for the first time between January 2011 and December 2014.

RESULTS

Hyponatremia (Na < 135 mEq/L) was seen in 77 patients (59%), of whom 29 had Grade 3 (120 ≤ Na < 130 mEq/L) or Grade 4 (Na < 120 mEq/L) hyponatremia. We divided patients into the hyponatremia group (patients with Na < 130 mEq/L) and the control group (patients with Na ≥ 130 mEq/L), and compared the results between the two groups. Three patients (2%) were diagnosed with the syndrome of inappropriate secretion of antidiuretic hormone. The serum sodium level before starting chemotherapy was significantly lower and white blood cell count was significantly higher in the hyponatremia group. Appetite loss was seen significantly more often in the hyponatremia group as the chemotherapy-related adverse effect. There was no significant difference in overall survival between the two groups.

CONCLUSIONS

Hyponatremia is a common adverse effect induced by cisplatin. Caution should be exercised with patients with a low sodium level before starting chemotherapy. Hyponatremia can be associated with other chemotherapy-related adverse effects, and it should therefore be treated correctly.

Double Trouble - Severe Hypernatremia Secondary to Central Diabetes Insipidus Complicated by Hypercalcemic Nephrogenic Diabetes Insipidus: A Case Report

BACKGROUND Patients with malignancies often have electrolyte abnormalities. We present a case of a patient with central diabetes insipidus secondary to metastatic pituitary invasion complicated by hypercalcemic nephrogenic diabetes insipidus. CASE REPORT We present a case of 40-year-old female with a history of stage IV breast cancer with skeletal and leptomeningeal metastasis, who was admitted with polyuria, polydipsia, and recent onset of confusion. The patient was found to have profound hypernatremia and severe hypercalcemia with normal parathyroid and vitamin D serum levels. Urine studies showed low urine osmolality and high urine output, despite the higher serum osmolality. The patient received 5% dextrose for rehydration, 1 dose of intravenous (IV) pamidronate, 1 dose of IV desmopressin, and 4 days of subcutaneous calcitonin 200 international units Q12H. Initially, her urine output in the hospital was in the range of 350-400 milliliters/hour, which responded well to 1 dose of 1-desamino-8d-arginine vasopressin (DDAVP). In the subsequent days, her confusion resolved with normalization of serum sodium and calcium, but she died because of the extensive malignancy. CONCLUSIONS Our case emphasizes the importance of identification of causes and complications of electrolyte abnormalities associated with metastatic cancers. These electrolyte abnormalities can be primary or paraneoplastic and should be actively pursued and treated in such cases.

Practical issues for the management of hyponatremia in oncology

Hyponatremia is common in cancer patients and has a negative impact on outcomes and survival. Both the diagnosis and treatment of hyponatremia are challenging. Easy-to-use, practical guidelines are needed. The aim of this article is to discuss practical issues related to the diagnostic workup and management of hyponatremia, with particular attention to complex patients, such as those affected by neoplastic diseases. Admittedly, these patients may present several comorbidities, which may cause sodium alterations. In addition, multidrug therapy may precipitate serum sodium fall. An algorithm for the diagnosis and treatment of hyponatremia was also developed, based on the discussion of the results of a questionnaire completed by the authors and of the published recommendations/guidelines on hyponatremia. The goal was to produce an algorithm that was as simple as possible but still comprehensive, without compromising information completeness. Many explanatory notes were added with the aim of guiding clinicians throughout the management of complex patients with hyponatremia, such as those with cancer. The resulting algorithm and supporting literature are presented.

Pancreatic Neuroendocrine Tumor Producing Insulin and Vasopressin

The objective of the study is to report a rare case of pancreatic neuroendocrine tumor (pNET) producing insulin and vasopressin. We describe the clinical presentation and management of a metastatic pNET with refractory hypoglycemia and progressive severe hyponatremia. A 52-year-old patient had abdominal pain leading to the diagnosis of a tumor that was initially presumed to be splenic in origin. Investigations ultimately identified a pancreatic mass that on biopsy proved to be a pNET. Eventually, he developed extensive liver metastases, and with tumor progression, he manifested hypoglycemia and severe hyponatremia. He was managed with multiple therapies including somatostatin analogue, peptide-receptor-radionuclide-therapy (PRRT), diazoxide, and everolimus; none of these therapeutic modalities was successful in controlling functional and structural progression of the tumor. Ultimately, the pNET proved fatal and autopsy confirmed widely metastatic disease that stained strongly and diffusely for vasopressin, a feature not seen in the previous liver biopsy. This case illustrates the challenges of diagnosis and management of aggressive insulin-producing pNETs and highlights the potential concomitant ectopic production of vasopressin leading to refractory hyponatremia.

[Endocrine paraneoplastic syndromes]

Endocrine paraneoplastic syndromes result from the production of bioactive substances from neoplastic cells, of endocrine or neuroendocrine origin. Typically these are located in the lungs, the gastrointestinal tract, pancreas, thyroid gland, adrenal medulla, skin, prostate or breast. In endocrine paraneoplastic syndromes the secretion of peptides, amines or other bioactive substances is always ectopic and not related to the anatomical source. The clinical presentation, however, is indistinguishable from a suspected eutopic endocrine tumor posing a diagnostic challenge. The most common endocrine paraneoplastic syndromes are based on the secretion of antidiuretic hormone (ADH) resulting in hyponatremia, secretion of adrenocorticotropic hormone (ACTH) or rarely corticotropin-releasing hormone (CRH) resulting in Cushing syndrome as well as secretion of growth hormone-releasing hormone resulting in acromegaly. Paraneoplastic endocrine syndromes mainly occur in highly malignant tumors; however, the development of these tumors does not necessarily correlate with tumor stage, malignant potential or prognosis. As endocrine paraneoplastic syndromes are a rare complication, there are hardly any evidence-based therapeutic recommendations. Treatment of the underlying tumor is the first choice and in a palliative setting symptomatic therapy is possible.

Cisplatin-induced syndrome of inappropriate antidiuretic hormone secretion (SIADH) with life-threatening hyponatraemia

We present a case of cisplatin-induced syndrome of inappropriate antidiuretic hormone (SIADH) in a patient with metastatic recurrent urothelial carcinoma. Cisplatin-induced SIADH is an uncommon but potentially life-threatening toxicity. Pharmacogenetic characteristics may result in different toxicity profiles in different populations. With such widespread use of cisplatin in a diverse range of cancers, prompt recognition is crucial to detect and prevent severe neurological sequelae.

An integrated analysis of hyponatremia in cancer patients receiving platinum-based or nonplatinum-based chemotherapy in clinical trials (JCOG1405-A)

Background

Hyponatremia is a common electrolyte abnormality in cancer patients who receive chemotherapy. Among anticancer agents, platinum-based agents are reported to cause chemotherapy-induced hyponatremia. However, the actual incidence and risk factors remain unknown.

Results

The reports of 29 trials were analyzed. The incidence of grade 3/4 hyponatremia was 11.9% in patients treated with platinum-based chemotherapy and 3.8% in those treated with nonplatinum-based regimens (P < 0.01). Univariable analysis revealed a high incidence of hyponatremia in patients receiving cisplatin, three-drug combination regimen, two-drug combination regimen with amrubicin or irinotecan, or high-dose cisplatin (weekly equivalent cisplatin dose ≥20 mg/m²), and in patients with small-cell lung cancer.

Conclusion

This is the first report of the actual incidence and the potential risk factors of chemotherapy-induced hyponatremia. Careful monitoring of serum sodium level is needed when platinum-based chemotherapy is administered.

Methods

This study included all clinical trials of systemic chemotherapies for solid cancers that were conducted by the Japan Clinical Oncology Group (JCOG) after January 2000 and of which the patient enrolment was completed by January 2014. The latest reports of each trial were used for analysis. The incidence of chemotherapy-induced grade 3/4 hyponatremia and the potential risk factors were investigated with univariable analysis.

In-patient Tolvaptan use in SIADH: care audit, therapy observation and outcome analysis

BACKGROUND

Indications for use of tolvaptan in SIADH-associated hyponatraemia remain controversial. We audited our local guidelines for Tolvaptan use in this situation to review treatment implications including drug safety, hospital admission episode analysis (episodes of liver toxicity, CNS myelinolysis, sodium-related re-admission rates), morbidity; mortality and underlying aetiologies.

METHODS

We report a retrospective case series analysis of on-going treatment outcomes (case-note review) for 31 patients (age 73.3 ± 10.5 years, 55% females) consecutively treated with Tolvaptan as in-patient for confirmed SIADH with persistent S/Na⁺ < 125 mmol/L despite removal of reversible causes and 24-48 h fluid restriction, and include longer-term outcome data (re-treatment/readmissions/mortality) for up to 4 years of follow-up. A minimum of 6 months follow-up data were reviewed unless the patient died before that period.

RESULTS

Short-term outcomes were favourable; 94%-achieved treatment targets after a mean of 3.48 ± 2.46 days. There was statistically significant rise in S/Na⁺ level after Tolvaptan treatment (before treatment: mean sodium 117.8 ± 3.73, 108-121 mmol/L and after treatment: mean sodium 128.7 ± 3.67, 125-135.2 mmol/L, P < .001). Although the target S/Na⁺ level was >125 mmol/L in fact one third (35%) of the patients achieved a S/Na⁺ level of >130 mmol/L by the time of hospital discharge. No patient experienced S/Na⁺ rise >12 mmol/L/24 h, drug-associated liver injury or CNS-myelinolysis. The average length of hospital stay following start of Tolvaptan treatment was 3.2 days. Relapse of hyponatraemia occurred in 26% of the patients, requiring retreatment with Tolvaptan. In all patients where either relapse of hyponatraemia occurred or readmission was necessary, SIADH was associated with malignancy, which was present overall in 60% of the group studied.

CONCLUSIONS

This study confirms the safety and efficacy of Tolvaptan in the treatment of SIADH-related significant, symptomatic hyponatraemia when used under specialist guidance and strict monitoring. A sodium level relapsing below the treatment threshold by 1 week after discontinuation is a good indicator of a patient group with re-treatment/longer-term therapy needs, all of whom had underlying malignancy. The criteria set locally in our trust to initiate Tolvaptan use also identifies a group where further investigation for underlying malignancy should be considered.

Efficacy of second-line treatment and importance of comorbidity scores and clinical parameters affecting prognosis in elderly patients with non-small cell lung cancer without epidermal growth factor receptor mutations

The present study investigated the importance of comorbidity scores and clinical parameters in elderly patients with non-small cell lung cancer (NSCLC) not harboring epidermal growth factor receptor (EGFR) mutations who received second-line chemotherapy. The present study also compared the efficacy of tyrosine kinase inhibitor and cytotoxic chemotherapy as second-line treatment in elderly patients. The present study retrospectively reviewed the treatment of elderly patients with NSCLC (≥70 years old) who received second-line chemotherapy at Korea University Guro Hospital. Patients who had an EGFR mutation were excluded from the analysis. Between 2005 and 2013, 126 patients were included in the present study. The median progression-free survival (PFS) and overall survival (OS) for all patients who received second-line treatment were 2.47 months [95% confidence interval (CI), 2.08-2.86] and 8.63 months (95% CI, 5.99-11.28), respectively. A total of 52 patients (41.3%) were treated with tyrosine kinase inhibitor (TKI) and 74 (58.7%) were treated with chemotherapy. No difference was observed in the median PFS and OS between the TKI and chemotherapy groups (P=0.287 for PFS and P=0.374 for OS). The Charlson comorbidity index was not associated with survival, whereas a simplified comorbidity score and clinical factors, including poor performance status, short PFS of first-line chemotherapy, presence of brain metastasis and low serum albumin and sodium levels were significant prognostic factors in these elderly patients. Second-line chemotherapy was not beneficial to patients who had at least 3 of these factors and a median OS of 1.73 months, whereas patients who had less than 2 of these factors had a median OS of 11.50 months. For elderly lung cancer patients without EGFR mutations, clinical parameters were the most important factors affecting survival, rather than the types of drugs.

Managing hyponatremia in lung cancer: latest evidence and clinical implications

Hyponatremia is the most common electrolyte disorder in lung cancer patients. This condition may be related to many causes including incidental medications, concurrent diseases and side effects of antineoplastic treatments or the disease itself. Although not frequently life-threatening, it is usually associated with prolonged hospitalization, delays in scheduled chemotherapy, worsening of patient performance status and quality of life and may also negatively affect treatment response and survival. Most of the available data focus on thoracic tumors, especially small-cell lung cancer (SCLC), where hyponatremia is frequently related to the syndrome of inappropriate secretion of antidiuretic hormone (SIADH). Few studies specifically focus on non-small cell lung cancer (NSCLC) patients. Hyponatremia treatment needs to be personalized based on severity and duration of sodium serum reduction, extracellular fluid volume and etiology. However, literature data highlight the importance of early correction of the serum concentration levels. To achieve this the main options are fluid restriction, hypertonic saline, loop diuretics, isotonic saline, tolvaptan and urea. The aim of this review is to analyze the role of hyponatremia in lung cancer patients, evaluating causes, diagnosis, management and clinical implications.

[Hyponatremia in emergency admissions - often dangerous]

Hyponatremia is the most common electrolyte disorder in clinical practice and associated with increased morbidity and mortality, independent of underlying disease. Untreated acute hyponatremia can cause substantial morbidity and mortality as a result of osmotically induced cerebral edema whilst over rapid correction of chronic hyponatremia can cause serious neurologic impairment and death resulting from osmotic demyelination. Still hyponatremia is often neglected and insufficiently addressed, most likely due to limited understanding of its pathophysiological mechanisms. Being familiar with only few basic principles of body fluid regulation may be a worthwhile investment into the clinical career and save patients' lives.