Prednisolone in the treatment of severe malignant hypercalcaemia in metastatic breast cancer: a randomized study

The current status and perspectives regarding the clinical implication of intracellular calcium in breast cancer

Calcium ions (Ca²⁺ ) act as second messengers in intracellular signaling. Ca²⁺ pumps, channels, sensors, and calcium binding proteins, regulate the concentrations of intracellular Ca²⁺ as a key regulator of important cellular processes such as gene expression, proliferation, differentiation, DNA repair, apoptosis, metastasis, and hormone secretion. Intracellular Ca²⁺ also influences the functions of several organelles, that include: the endoplasmic reticulum, mitochondria, the Golgi, and cell membrane both in normal and breast cancer cells. In breast cancer, the disruption of intracellular: Ca²⁺ homeostasis may cause tumor progression by affecting key factors/pathways including phospholipase C (PLC), inositol 1,4,5-trisphosphate (IP3), calmodulin (CaM), nuclear factor of activated T-cells (NFAT), calpain, calmodulin-dependent protein kinase II (CaMKII), mitogen-activated protein kinase (MAPK), epithelial-mesenchymal transition (EMT), vascular endothelial growth factor (VEGF), poly (ADP-Ribose) polymerase-1 (PARP1), estrogen, and estrogen receptor. Because the foregoing molecules play crucial roles in breast cancer, the factors/pathways influencing intracellular Ca²⁺ concentrations are putative targets for cancer treatment, using drugs such as Mephebrindole, Tilapia piscidin 4, Nifetepimine, Paricalcitol, and Prednisolone. We have explored the factors/pathways which are related to breast cancer and Ca²⁺ homeostasis and signaling in this review, and also discussed their potential as biomarkers for breast cancer staging, prognosis, and therapy.

Hypercalcemia in the Intensive Care Unit: A Review of Pathophysiology, Diagnosis, and Modern Therapy

Hypercalcemia may be seen in a variety of clinical settings and often requires intensive management when serum calcium levels are dramatically elevated. All of the many etiologies of mild hypercalcemia can lead to severe hypercalcemia. Knowledge of the physiologic mechanisms involved in maintaining normocalcemia and basic pathophysiology is essential for making a timely diagnosis and hence prompt institution of etiology-specific therapy. The development of new medications and critical reviews of traditional therapies have changed the treatment paradigm for severe hypercalcemia, calling for a more limited role for aggressive isotonic fluid administration and furosemide and an expanded role for calcitonin and the bisphosphonates. Experimental therapies such as denosumab show promise.

Systematic review of the clinical effect of glucocorticoids on nonhematologic malignancy

BACKGROUND

Glucocorticoids are often used in the treatment of nonhematologic malignancy. This review summarizes the clinical evidence of the effect of glucocorticoid therapy on nonhematologic malignancy.

METHODS

A systematic review of clinical studies of glucocorticoid therapy in patients with nonhematologic malignancy was undertaken. Only studies having endpoints of tumor response or tumor control or survival were included. PubMed, EMBASE, the Cochrane Register/Databases, conference proceedings (ASCO, AACR, ASTRO/ASTR, ESMO, ECCO) and other resources were used. Data was extracted using a standard form. There was quality assessment of each study. There was a narrative synthesis of information, with presentation of results in tables. Where appropriate, meta-analyses were performed using data from published reports and a fixed effect model.

RESULTS

Fifty four randomized controlled trials (RCTs), one meta-analysis, four phase l/ll trials and four case series met the eligibility criteria. Clinical trials of glucocorticoid monotherapy in breast and prostate cancer showed modest response rates. In advanced breast cancer meta-analyses, the addition of glucocorticoids to either chemotherapy or other endocrine therapy resulted in increased response rate, but not increased survival. In GI cancer, there was one RCT each of glucocorticoids vs. supportive care and chemotherapy +/- glucocorticoids; glucocorticoid effect was neutral. The only RCT found of chemotherapy +/- glucocorticoids, in which the glucocorticoid arm did worse, was in lung cancer. In glucocorticoid monotherapy, meta-analysis found that continuous high dose glucocorticoids had a detrimental effect on survival. The only other evidence, for a detrimental effect of glucocorticoid monotherapy, was in one of the two trials in lung cancer.

CONCLUSION

Glucocorticoid monotherapy has some benefit in breast and prostate cancer. In advanced breast cancer, the addition of glucocorticoids to other therapy does not change the long term outcome. In GI cancer, glucocorticoids most likely have a neutral effect. High dose continuous glucocorticoids have a detrimental effect in nonhematologic malignancy. Glucocorticoid therapy might have a deleterious impact in lung cancer.

Bone and Mineral Metabolism

Although bones are normally thought of as supporting structures that fracture when one falls, bone is actually a very active metabolic organ. It is vital in the regulation of calcium and phosphate metabolism, magnesium storage, and in buffering metabolic acido-sis. Bone and mineral metabolism and some of their disorders are presented in this article.

Oral clodronate in breast cancer patients with bone metastases: a randomized study

OBJECTIVES

To investigate the effect of the bisphosphonate clodronate on the occurrence of skeletal events (hypercalcaemia, fractures and radiotherapy) in breast cancer patients with bone metastases.

DESIGN

Prospective, randomized, controlled, clinical trial.

SETTING

A department of oncology in a university hospital.

SUBJECTS

One hundred patients who received firstline systemic antineoplastic treatment for metastatic breast cancer with bone involvement were randomized to receive clodronate as two 400 mg capsules twice a day for 2 years or no additional therapy.

RESULTS

In the clodronate group the number of skeletal events was reduced to 14 events in 48 evaluable patients as compared with 21 events in 51 evaluable control patients. The time to the first skeletal event was significantly longer in the clodronate group than in the control group (P = 0.015) and the most distinct difference was a lower occurrence of fractures in the clodronate group (P = 0.023). After 15 months the effect of clodronate tended to decline as the need for radiotherapy increased in the clodronate group compared with the control group (P = 0.069). Significant improvements in several quality-of-life aspects were seen in both groups during the first 6 months, but there was no significant difference between the groups. No effect was observed on time to radiologically evaluated disease progression in bone or on survival. The most frequent side-effects resulting in discontinuation of clodronate were nausea and diarrhoea.

CONCLUSION

Oral clodronate is associated with a temporary reduction of morbidity related to bone metastases in breast cancer patients.

Survival in breast cancer patients after the first episode of hypercalcaemia

OBJECTIVES

To investigate hypercalcaemia (serum ionized calcium (S-Ca2+) > 1.35 mmol L(-1)) in breast cancer patients before and after the introduction of bisphosphonates and the effect of disease- and treatment-related factors on survival.

DESIGN

Prospective and retrospective registration of covariates.

SETTING

A department of oncology in a university hospital.

SUBJECTS

A consecutive cohort of 212 hypercalcaemic patients never treated with bisphosphonate was identified prospectively (period 1) and 193 patients with metastases were classified into three groups: mild (S-Ca2+ < 1.48: n=102). moderate (1.48 < or = S-Ca2+ < or = 1.60; n=41). and severe hypercalcaemia (S-Ca2+ > 1.60 mmol L(-1); n=50). Fifty-one patients with severe hypercalcaemia all treated with bisphosphonate except one were identified retrospectively (period 2).

RESULTS

For period 1 median survival was 6.7 months. Survival was significantly decreased in the two groups with the highest initial S-Ca2+ (P < 0.0001). Median survival times in severely hypercalcaemic patients from periods 1 and 2 were 1.4 (9 5(% confidence interval 0.8-2.1) and 2.2 (95% confidence interval 1.3-3.1) months, respectively. In a Cox model for period 1 significant covariates were: WHO performance, extent of metastases, whether systemic anticancer treatment could be given, and haemoglobin, but not S-Ca2+.

CONCLUSION

Prognosis is poor in hypercalcaemic breast cancer patients with WHO performance 3-4 and advanced metastatic disease when effective systemic treatment can no longer be offered. Bisphosphonate treatment does not seem to improve survival in severe hypercalcaemia. Antihypercalcaemic treatment of mild malignancy-associated hypercalcaemia appears not to be vital. Therapeutic efforts should be aiming at patients with moderate hypercalcaemia.

Acute management of cancer-related hypercalcemia

OBJECTIVE

To review the pathogenesis and pharmacologic treatment of acute hypercalcemia associated with malignancy.

DATA SOURCES

A MEDLINE search (1966 to 1995) of the English-language literature pertaining to acute hypercalcemia was performed. Additional literature was obtained from reference lists of articles identified through the search.

STUDY SELECTION AND DATA EXTRACTION

All articles discussing the etiology and medical management of cancer-related acute hypercalcemia were considered in this review. Clinical trials reporting efficacy and safety of antihypercalcemic agents were also included. Information selected in the review was based on the discretion of the authors.

DATA SYNTHESIS

Hypercalcemia is a life-threatening disorder associated with malignancy. It occurs in approximately 10-20% of patients with cancer. A variety of medications have been used in the management of hypercalcemia including bisphosphonates, calcitonin, furosemide, gallium nitrate, glucocorticoids, NaCl 0.9%, and plicamycin. Each of these agents has been reviewed with consideration of pharmacologic mechanism of action, evaluation of clinical trials, recommended dosages, efficacy, safety, cost, and role in treating cancer-related acute hypercalcemia.

CONCLUSIONS

Immediate management of cancer-related acute hypercalcemia to prevent death and provide symptomatic relief is warranted. Severity determined by symptoms, calcium concentrations, and the overall status of the patient are important considerations in selecting appropriate therapy. Although the specific role of individual agents may vary, hydration remains the cornerstone of therapy. NaCl 0.9%, calcitonin, and pamidronate disodium have established roles as dominant first-line agents for the management of acute hypercalcemia associated with malignancy.

Hypercalcemia in patients with breast cancer: a survival study

In a retrospective study survival after hypercalcemia in breast cancer patients has been investigated. A group of 72 patients were treated with bisphosphonate APD [3-(amino-1,1-hydroxypropylidene)bisphosphonate] and third-generation amino-containing bisphosphonates between January 1980 and October 1992. A median survival of 4.5 months was found. In a multivariate analysis, four independent prognostic factors for survival have been found: the interval between first relapse and hypercalcemia, sites of metastases at the moment of hypercalcemia, primary treatment, and the level of serum alkaline phosphatase. Patients with a "flare" reaction on tamoxifen treatment and patients with a normal serum alkaline phosphatase level and bone metastases only had a prolonged survival. Hypercalcemia associated with visceral metastases carried a very poor prognosis. The level of serum calcium in this series of patients was no prognostic indicator for survival.

Tamoxifen and hypercalcaemia

The present case demonstrates the importance of close observation, also of serum calcium, when initiating tamoxifen therapy, especially in patients with known osseous metastases. Hypercalcaemia should also be considered as a possible cause of CNS symptoms in patients newly started on endocrine treatment. Hydration with saline is the first step in the management of hypercalcaemia. In patients with a serum calcium level > 3.50 mmol/l (serum ionised calcium approximately 2.00 mmol/l) hydration should be combined with bisphosphonates.