The incidence and prognostic significance of humoral hypercalcemia in renal cell carcinoma

Clinicopathological and Preclinical Patient-Derived Model Studies Define High Expression of NRN1 as a Diagnostic and Therapeutic Target for Clear Cell Renal Cell Carcinoma

Background

Acquired therapeutic resistance and metastasis/recurrence remain significant challenge in advance renal cell carcinoma (RCC), thus the establishment of patient-derived cancer models may provide a clue to assess the problem. We recently characterized that neuritogenesis-related protein neuritin 1 (NRN1) functions as an oncogene in testicular germ cell tumor. This study aims to elucidate the role of NRN1 in RCC.

Methods

NRN1 expression in clinical RCC specimens was analyzed based on immunohistochemistry. NRN1-associated genes in RCC were screened by the RNA-sequencing dataset from The Cancer Genome Atlas (TCGA). RCC patient-derived cancer cell (RCC-PDC) spheroid cultures were established and their viabilities were evaluated under the condition of gene silencing/overexpression. The therapeutic effect of NRN1-specific siRNA was evaluated in RCC-PDC xenograft models.

Results

NRN1 immunoreactivity was positively associated with shorter overall survival in RCC patients. In TCGA RCC RNA-sequencing dataset, C-X-C chemokine receptor type 4 (CXCR4), a prognostic and stemness-related factor in RCC, is a gene whose expression is substantially correlated with NRN1 expression. Gain- and loss-of-function studies in RCC-PDC spheroid cultures revealed that NRN1 significantly promotes cell viability along with the upregulation of CXCR4. The NRN1-specific siRNA injection significantly suppressed the proliferation of RCC-PDC-derived xenograft tumors, in which CXCR4 expression is significantly repressed.

Conclusion

NRN1 can be a potential diagnostic and therapeutic target in RCC as analyzed by preclinical patient-derived cancer models and clinicopathological studies.

Functional inhibition of cancer stemness-related protein DPP4 rescues tyrosine kinase inhibitor resistance in renal cell carcinoma

Tyrosine kinase inhibitors (TKIs) are used as targeted drugs for advanced renal cell carcinoma (RCC), although most cases eventually progress by acquiring resistance. Cancer stemness plays critical roles in tumor aggressiveness and therapeutic resistance, and dipeptidyl peptidase IV (DPP4) has been recently identified as a cancer stemness-related protein. A question arises whether DPP4 contributes to TKI efficacy in RCC. We established patient-derived RCC spheroids and showed that DPP4 expression is associated with stemness-related gene expression. TKI sunitinib resistance was rescued by DPP4 inhibition using sitagliptin or specific siRNAs in RCC cells and tumors. DPP4 expression can be inducible by retinoic acid and repressed by ALDH1A inhibition. Among type 2 diabetes patients with clinical RCC tumors, higher TKI efficacy is observed in those bearing DPP4^high tumors treated with DPP4 inhibitors. This study provides new insights into TKI resistance and drug repositioning of DPP4 inhibitor as a promising strategy for advanced RCC.

Methods for the evaluation of biomarkers in patients with kidney and liver diseases: multicentre research programme including ELUCIDATE RCT

Background

Protein biomarkers with associations with the activity and outcomes of diseases are being identified by modern proteomic technologies. They may be simple, accessible, cheap and safe tests that can inform diagnosis, prognosis, treatment selection, monitoring of disease activity and therapy and may substitute for complex, invasive and expensive tests. However, their potential is not yet being realised.

Design and methods

The study consisted of three workstreams to create a framework for research: workstream 1, methodology – to define current practice and explore methodology innovations for biomarkers for monitoring disease; workstream 2, clinical translation – to create a framework of research practice, high-quality samples and related clinical data to evaluate the validity and clinical utility of protein biomarkers; and workstream 3, the ELF to Uncover Cirrhosis as an Indication for Diagnosis and Action for Treatable Event (ELUCIDATE) randomised controlled trial (RCT) – an exemplar RCT of an established test, the ADVIA Centaur® Enhanced Liver Fibrosis (ELF) test (Siemens Healthcare Diagnostics Ltd, Camberley, UK) [consisting of a panel of three markers – (1) serum hyaluronic acid, (2) amino-terminal propeptide of type III procollagen and (3) tissue inhibitor of metalloproteinase 1], for liver cirrhosis to determine its impact on diagnostic timing and the management of cirrhosis and the process of care and improving outcomes.

Results

The methodology workstream evaluated the quality of recommendations for using prostate-specific antigen to monitor patients, systematically reviewed RCTs of monitoring strategies and reviewed the monitoring biomarker literature and how monitoring can have an impact on outcomes. Simulation studies were conducted to evaluate monitoring and improve the merits of health care. The monitoring biomarker literature is modest and robust conclusions are infrequent. We recommend improvements in research practice. Patients strongly endorsed the need for robust and conclusive research in this area. The clinical translation workstream focused on analytical and clinical validity. Cohorts were established for renal cell carcinoma (RCC) and renal transplantation (RT), with samples and patient data from multiple centres, as a rapid-access resource to evaluate the validity of biomarkers. Candidate biomarkers for RCC and RT were identified from the literature and their quality was evaluated and selected biomarkers were prioritised. The duration of follow-up was a limitation but biomarkers were identified that may be taken forward for clinical utility. In the third workstream, the ELUCIDATE trial registered 1303 patients and randomised 878 patients out of a target of 1000. The trial started late and recruited slowly initially but ultimately recruited with good statistical power to answer the key questions. ELF monitoring altered the patient process of care and may show benefits from the early introduction of interventions with further follow-up. The ELUCIDATE trial was an ‘exemplar’ trial that has demonstrated the challenges of evaluating biomarker strategies in ‘end-to-end’ RCTs and will inform future study designs.

Conclusions

The limitations in the programme were principally that, during the collection and curation of the cohorts of patients with RCC and RT, the pace of discovery of new biomarkers in commercial and non-commercial research was slower than anticipated and so conclusive evaluations using the cohorts are few; however, access to the cohorts will be sustained for future new biomarkers. The ELUCIDATE trial was slow to start and recruit to, with a late surge of recruitment, and so final conclusions about the impact of the ELF test on long-term outcomes await further follow-up. The findings from the three workstreams were used to synthesise a strategy and framework for future biomarker evaluations incorporating innovations in study design, health economics and health informatics.

Trial registration

Current Controlled Trials ISRCTN74815110, UKCRN ID 9954 and UKCRN ID 11930.

Funding

This project was funded by the NIHR Programme Grants for Applied Research programme and will be published in full inProgramme Grants for Applied Research; Vol. 6, No. 3. See the NIHR Journals Library website for further project information.

Recent Aspects in the Diagnosis and Prognosis of Bladder Cancer

Epidemiologic studies have stated the progressive increase of bladder tumors during the last decades. The aim of our review is to refer to factors implicated in bladder carcinogenesis (such as activated oncogenes, growth factors and chromosomal aberrations) and to resistance to drug uptake (i.e., multidrug resistance gene and P-glycoprotein). The review also provides information of diagnostic and prognostic significance, based on DNA analysis of transitional cancer cells. In addition to cytometric data, alternative counterings for estimation of the S-phase fraction, useful in indicating the biologic behavior of bladder cancer, are presented. Knowledge of such mechanisms results in a better approach to the diagnosis, prognosis and prevention of bladder carcinomas, especially those that do not respond to systemic intravesical chemotherapy. We have tried to mention all significant factors related to the development of bladder cancer. We conclude that the progress made in understanding the pathogenesis of bladder cancer has been significant. However, more studies are needed in order to introduce and adopt reliable criteria to accurately predict the clinical behavior.

A systematically structured review of biomarkers of dying in cancer patients in the last months of life; An exploration of the biology of dying

BACKGROUND

The Neuberger review made a number of recommendations to improve end of life care, including research into the biology of dying. An important aspect of the biology of dying is the identification of biomarkers as indices of disease processes. Biomarkers have the potential to inform the current, limited understanding of the dying process and assist clinicians in recognising dying, in particular how to distinguish dying from reversible acute deterioration.

OBJECTIVES

To critically appraise the literature on biological factors that may be used as prognostic indicators in advanced cancer patients and to identify candidate biomarkers of the dying process that can be measured serially in cancer patients' bodily fluids.

METHODS

A systematically structured review was conducted using three electronic databases. A hand search of six peer-reviewed journals and conference abstracts was also conducted. Studies reporting prognostic biomarkers in cancer patients with a median survival of ≤90 days and post-mortem studies were included. Final levels of evidence and recommendations were made using the Evidence Based Medicine modified GRADE system.

RESULTS

30 articles were included. Seven prognostic biological factors demonstrated Grade A evidence (lymphocyte count, white blood cell count, serum C-reactive protein, albumin, sodium, urea and alkaline phosphatase). An additional eleven prognostic factors were identified with Grade B evidence (platelet count, international normalised ratio, serum vitamin B12, prealbumin, bilirubin, cholesterol, aspartate aminotransferase, alanine transaminase, lactate dehydrogenase, pseudocholinesterase and urate). A number of biomarkers were specifically identified in the last two weeks of life but limitations exist. No post-mortem studies met the inclusion criteria.

CONCLUSION

The biology of dying is an important area for future research, with the evidence focused on signs, symptoms and prognostic factors. This review identifies a number of common themes shared amongst advanced cancer patients and highlights candidate biomarkers which may be indicative of a common biological process to dying.

Malignancy-Related Hypercalcemia in Advanced Solid Tumors: Survival Outcomes

Purpose

Malignancy-related hypercalcemia (MRH) is associated with a dismal prognosis. The widespread use of bisphosphonates (BPs), availability of more effective drugs in cancer treatment, and improvement in supportive care might have attenuated its impact.

Patients and Methods

To assess overall survival (OS) of patients with MRH in a contemporary setting, we conducted a retrospective analysis of 306 patients with solid cancer hospitalized for symptomatic hypercalcemia. A multivariable Cox proportional hazards regression model was performed to evaluate possible prognostic factors associated with MRH.

Results

All patients had serum ionized calcium > 5.5 mg/dL or total Ca > 10.5 mg/dL. Median age was 57 years, and the majority had squamous cell carcinoma (62%) and Eastern Cooperative Oncology Group performance status > 1 (96%). Head and neck was the most frequent primary site (28%). Forty-five percent had no previous chemotherapy (CT), and subsequent CT was administered to 32%. Eighty-three percent received BP with no survival gain. Median OS was 40 (95% CI, 33 to 47) days. Patients with a performance status > 2, altered mental status, C-reactive protein > 30 mg/L, albumin < 2.5 g/dL, or body mass index < 18 kg/m² had significantly poorer survival in a univariable analysis, and longer OS was related to treatment-naive patients, subsequent CT, and breast primary site. In the multivariable analysis, subsequent CT led to a median OS improvement of 144 versus 25 days (hazard ratio, 0.24; 95% CI, 0.14 to 0.40; P < .001).

Conclusion

In a contemporary setting, MRH remains a marker of poor prognosis. Patients treated with CT had better survival, which suggests that appropriate treatment of selected patients might alter the course of this syndrome.

Tumor signatures of PTHLH overexpression, high serum calcium, and poor prognosis were observed exclusively in clear cell but not non clear cell renal carcinomas

High serum calcium (Ca) due to aberrant secretion of tumor parathyroid hormone-like hormone (PTHLH) is a well-known paraneoplastic sign and is associated with poor prognosis in patients with renal cell carcinoma (RCC). However, the status of serum Ca and tumor PTHLH expression have not been verified using the 2004 World Health Organization (WHO) renal tumor classification. We retrospectively reviewed corrected serum Ca levels at initial onset (n = 683) and/or as of recurrence (n = 71) in patients with RCC. We also examined a total of 623 renal parenchymal tumor samples for PTHLH mRNA expressions by quantitative real-time PCR. High serum Ca concomitant with PTHLH overexpression in tumors was observed exclusively in clear cell RCC but not in other non clear cell subtype tumors, including papillary, chromophobe, collecting-duct, unclassified, and other rare subtype RCCs or in benign oncocytomas and angiomyolipomas. In clear cell RCC, PTHLH expression was significantly high in male patients, and was associated with a symptomatic presentation, higher grade, and higher stage cases, whereas it was not associated with VHL gene status. Univariate analyses demonstrated that high PTHLH expression was strongly associated with poor outcome both in overall survival (OS) and disease-free survival (DFS) for patients who underwent standard nephrectomy. Further multivariate Cox analyses revealed that the PTHLH expressions remained as independent prognostic parameters for OS but not for DFS. These data suggest that the previously characterized tumor signatures of high serum Ca due to high PTHLH expression and poor prognosis are clear cell RCC-specific features, whereas these characteristics are rare in non clear cell RCCs.

Lymphopenia is an independent predictor of inferior outcome in clear cell renal carcinoma

PURPOSE

A low absolute lymphocyte count is a likely index of poor systemic immunity that may be associated with aggressive features and inferior survival in patients with clear cell renal cell carcinoma.

MATERIALS AND METHODS

To determine the absolute lymphocyte count we retrospectively analyzed the preoperative blood count of 430 patients with a mean age of 60 years treated with primary surgical resection at our cancer center. Absolute lymphocyte count values as a continuous variable and at a level below 1,300 cells per μl, which was our lowest reference value, were correlated with nuclear grade, pathological stage and TNM stage. We used the Kaplan-Meier method to estimate overall survival, stratified by absolute lymphocyte count status.

RESULTS

As a continuous variable, low absolute lymphocyte count was associated with higher grade (p = 0.009), and higher pT stage (p = 0.034) and TNM stage (p <0.0001). Lymphopenia below 1,300 cells per μl was associated with high grade (p = 0.0043), pT stage (p = 0.051) and TNM stage (p <0.0001). At a median followup of 33.5 months lymphopenia was associated with inferior overall survival in a univariate model (p <0.0001), and on multivariate analysis independent of pT, N and M stages, patient age, grade, smoking history and comorbidities (p = 0.0102). Lymphopenia was also associated with inferior overall survival in a subset of young patients (age 60 years or less) with no distant metastasis (p = 0.014).

CONCLUSIONS

In 430 patients with clear cell renal cell carcinoma lymphopenia was associated with lower overall survival independent of pT and TNM stages, nuclear grade, age, tobacco smoking and comorbidity index.

Association of abnormal preoperative laboratory values with survival after radical nephrectomy for clinically confined clear cell renal cell carcinoma

OBJECTIVES

To determine whether preoperative laboratory values are independently associated with death from clinically confined clear cell renal cell carcinoma (RCC) after radical nephrectomy.

METHODS

We identified 1707 patients with clinically confined (pNx/pN0, pM0), unilateral, sporadic clear cell RCC treated with radical nephrectomy between 1970 and 2002. Associations of abnormal preoperative laboratory values including hypercalcemia, anemia, elevated erythrocyte sedimentation rate (ESR), and elevated alkaline phosphatase with death from RCC were evaluated using Cox proportional hazards regression models, both univariately and multivariately by adjusting for known prognostic features of the 2002 primary tumor classification, tumor size, nuclear grade, and coagulative tumor necrosis.

RESULTS

At last follow-up, 1009 patients had died, including 425 who died from RCC at a median of 3.0 years after surgery (range, 0 to 26 years). Even after adjusting for known prognostic features, 9% of patients with preoperative hypercalcemia exhibited significantly increased likelihood of dying from RCC compared with patients with normal or lower levels of serum calcium (relative ration [RR] 1.64; P = 0.002). Similarly, preoperative anemia (35% of patients; RR 1.27; P = 0.026) and elevated ESR (44% of patients; RR 1.66; P = 0.003) portended an increased risk of death from RCC even after multivariate adjustment.

CONCLUSIONS

Abnormal preoperative laboratory values including hypercalcemia, anemia, and elevated ESR are independently associated with increased risk of cancer-specific death from clinically confined clear cell RCC. Consideration of these variables in future models may improve prognostic accuracy. We believe these factors should be routinely assessed and included in prospective studies of outcome in RCC patients.

Differential diagnosis of hypercalcemia in renal malignancy

We report a case of large cell B-cell lymphoma of the kidney associated with humoral hypercalcemia of malignancy. A 70-year-old man presented with renal failure and hypercalcemia. After the workup, the patient was thought to have renal cell carcinoma and underwent radical nephrectomy. The pathologic evaluation showed a large cell lymphoma with a B-cell phenotype. Reevaluation of the patient's serum revealed a high calcitriol level with low parathyroid hormone and parathyroid hormone-related protein levels, consistent with the final pathologic findings. The differential diagnosis of hypercalcemia in renal malignancy is presented.

Cancer-associated hypercalcemia treated with intravenous diphosphonates: a survival and prognostic factor analysis

BACKGROUND

Cancer-associated hypercalcemia (CAH) is the most frequent metabolic disorder in cancer patients. We retrospectively reviewed the outcome and prognostic factors for patients with CAH being treated with standard intravenous disphosphonates.

MATERIALS AND METHODS

Two hundred sixty patients were reviewed. Overall survival and prognostic factors were analyzed. Relative risks (RR) for early death (within 60 days) were assessed (Fischer exact test and logistic regression model).

RESULTS

Median survival was 64 days (range, 12-1,955+). Multivariate analysis identified the following factors as poor survival predictors: serum corrected calcium >2.83 mmol/l [hazard ratio (HR) = HR 2.21], albuminemia <35.5 (HR 2.41), squamous cell carcinoma (HR 2.64), bone metastasis (HR 1.44), and liver metastasis (HR 2..22). One hundred twenty-one patients died within 60 days. For those patients, the logistic regression model identified four independent predicting factors for early death: calcemia >2.83 mmol/l (RR 5.07), hypoalbuminemia (RR 7.42), liver metastasis (RR 4.34), and squamous cell carcinomas (RR 2.21).

DISCUSSION

Despite intravenous diphosphonate, CAH is still associated with poor outcome. Simple bedside parameters may estimate the risk of early deaths.

Renal cell carcinoma presenting with paraneoplastic hypercalcemic coma: a case report and review of the literature

We report a case of a 62-year-old woman with renal cell carcinoma (RCC) presenting with a hypercalcemia-induced coma. A laboratory evaluation indicated nonparathyroid-mediated hypercalcemia with an initial serum calcium level of 18.6 mg/dL. Our patient's parathyroid hormone (PTH)-related peptide level was undetectable. Initial imaging was negative, but PET scan identified a mass in the upper pole of the left kidney. Our patient underwent partial nephrectomy, and the mass was identified as RCC on final pathology. After surgery, her hypercalcemia resolved and PTH returned to normal limits. This case report describes a patient with RCC with the unusual presentation of hypercalcemic coma. We review the differential diagnosis of malignant hypercalcemia and the evaluation of hypercalcemia occurring with RCC. This case illustrates the need to carefully review and interpret all available data, especially when conventional testing in the work-up of hypercalcemia is unrevealing.

A Belgian registry of interleukin-2 administration for treatment of metastatic renal cell cancer and confrontation with literature data

In an effort to map the use of interleukin-2 (IL-2) treatment in patients with clear cell renal cell cancer (RCC) in Belgian hospitals, 44 cases were registered from 9 hospitals between February 2003 and June 2006. It was demonstrated that the majority of these patients were treated with subcutaneous (SC) IL-2. Other methods such as the inhalation of the drug in case of intrathoracic disease or high dose intravenous (IV) administration were much less frequent (3 and 0 cases in this registry, respectively). The results of antitumour activity (around 16% partial response-absence of complete responses) and toxicity of this drug correlate with observations from the literature with the SC administration. In view of the poor results and tolerance with the currently used cytokines (IL-2 or interferon-alfa), much hope is directed towards the development of the novel targeted drugs like sunitinib or sorafenib used alone or in combination with cytokines in this disease.

Oncologic Emergencies

It has been estimated that genitourinary malignancies will account for 25% of new cancer diagnoses in the United States in 2005 (Jemal et al. 2005). While the incidence of many of these malignancies has increased over the past two decades, the mortality rates appear to be decreasing. Early cancer detection combined with improvements in surgical and nonsurgical oncologic therapy account for these trends. Although not common, newly diagnosed cancer patients occasionally present in an emergent, life-threatening manner that warrants immediate medical or surgical intervention. As the prevalence of genitourinary malignancies continues to expand, additional patients can be expected to develop disease or treatment-related complications. This chapter will serve to review the diagnosis and management of oncologic emergencies as they pertain to the urologist.

Prognosis of hypercalcemia in aerodigestive tract cancers: Study of 136 recent cases

Recent data issuing the prognostic impact of hypercalcemia on outcome of aerodigestive tract cancers are spare. To assess the prognosis and the survival of head and neck cancer patients with hypercalcemia, we reviewed 136 recent successive cases, including also oesophageal and lung cancers. Data were collected from a retrospective database (July 2002-January 2004). Hypercalcemia was defined by calcemia level above 2.55 mmol/l. Univariate analysis for prognosis was performed with Mann-Whitney test (continuous variables) and Odd Ratio with 95% confidence interval (categorical variables). The primary locations were : oropharynx and oral cavity (79, 58%), hypopharynx (13, 9.5%), larynx (10, 7.3%), oesophagus (17, 12.5%) and lung (17, 12.5%). There were 23 females and 123 males, with a median age of 53 (18-86). The incidence of bone metastasis was low: 20/136, 14.5%. At cancer diagnosis, 32 hypercalcemia were observed. With a median follow-up of 88 days (2-553), we observed 98 deaths (overall mortality=72%). The median overall survival was 35 days (2-553+). The pejorative prognostic factors were: male gender (OR=2.64 CI 95% 1.07-6.82), age inferior to 50 (OR=2.67 CI 95% 1.23-5.8), presence of distant metastasis (OR=4.45 CI 95% 1.8-11.01), elevation of alkaline phosphatases (OR=7 CI 95% 2.73-17.9) and need of hospitalization for intravenous hydratation (OR=5.11 CI 95% 1.99-13.17). We observed 39 recurrences of hypercalcemia. The predictive factors for recurrence of hypercalcemia were: age superior to 50 (OR=4.61 CI 95% 2.02-10.52), male gender (OR=38.22 CI 95% 12.2-89), calcemia level superior to 2.7 mmol/l (OR=3.08 CI 95% 1.42-6.64) and absence of diphosphonates (bisphosphonates: OR=2.16 CI 95% 1.01-4.63). Despite use of diphosphonates (infusions of pamidronate), hypercalcemia is associated with very poor prognosis. Tumour location and level of calcemia had no prognostic value.

Parathyroid Hormone-Related Protein and Serum Calcium in Patients with Renal Cell Carcinoma

OBJECTIVE

To evaluate serum parathyroid hormone-related protein (PTHrP) in relation to serum calcium and clinical outcome of patients with renal cell carcinoma.

METHODS

Sera from 243 patients with renal cell carcinoma were collected prior to therapy. Serum PTHrP was analyzed using an immunoradiometric assay. Tumour stage, nuclear grade, corrected serum calcium, and survival were assessed.

RESULTS

Serum PTHrP was detectable in 37/243 sera (15%) and hypercalcaemia (> or =2.60 mmol/l) in 32/220 (15%). A positive correlation between serum PTHrP and serum calcium was found (r = 0.326; p < 0.01). Following subdivision of the material, based on storage time, the frequency of detectable serum PTHrP seemed to decrease with time. Serum calcium, but not serum PTHrP, was correlated to tumour stage (p < 0.001). Survival was similar for patients with detectable and undetectable PTHrP, but those with hypercalcaemia had a significantly shorter survival time compared to those with normal serum calcium (p < 0.001). A multivariate analysis showed that tumour stage and serum calcium were independent prognostic factors, but not grade or PTHrP.

CONCLUSIONS

A positive relation of serum PTHrP to serum calcium was demonstrated in patients with renal cell carcinoma. Hypercalcaemia but not serum PTHrP predicted a worse prognosis.

Characterization of bone metastases in patients with renal cell cancer

OBJECTIVE

To characterize the clinical features of bone metastases in patients with renal cell carcinoma (RCC) treated with interleukin-2 therapy. Bone lesions contribute to significant morbidity and mortality, and although present in up to half of patients with RCC, their behaviour and response to therapy have not been well characterized.

PATIENTS AND METHODS

We evaluated skeletal metastases in 19 patients with bone lesions who received either moderate- or high-dose interleukin-2 therapy. Data on bone disease, including location and number of bone lesions, need for bone-specific therapies and use of pain medications, were noted. The response of bone lesions to interleukin-2 was compared with the response of other systemic metastatic sites.

RESULTS

Skeletal metastases resulted in significant morbidity by causing pain (75%) and other complications requiring surgical and/or radiotherapeutic intervention (94%) before beginning interleukin-2 therapy. In most patients the response of bone lesions to interleukin-2 was similar to that in their other systemic sites. Treatment with interleukin-2 had no significant effect on the requirement for pain medication for bone pain. However, it may have prevented skeletal complications requiring surgery or radiotherapy. None of the patients had hypercalcaemia; there was no significant association between bone metastases and elevated alkaline phosphatase levels.

CONCLUSIONS

Skeletal metastases are a significant contributor to morbidity among patients with RCC. Bone lesions respond similarly to interleukin-2 therapy as other systemic sites. Bisphosphonates appear promising for these predominantly osteolytic lesions.

Hypercalcemia upon recurrence of renal cell carcinoma producing parathyroid hormone-related protein

We established a new renal carcinoma cell line that produces parathyroid hormone-related protein (PTHrP) and interleukin-6 in culture. The cellular production of PTHrP was confirmed by Northern blot analysis and immunofluorescence examination. Bone and lung metastases occurred simultaneously 3.5 years after surgery. The patient did not show hypercalcemia at this time, despite the presence of multiple osteolytic metastases. About 7 months after bone metastasis was first shown, serum PTHrP was detected by means of an immunoradiometric assay and the calcium level was found to be elevated to 3.29 mmol/l. The hypercalcemia was successfully controlled by i.v. administration of bisphosphonates.

Parathyroid hormone-related peptide and survival of patients with cancer and hypercalcemia

PURPOSE

Parathyroid hormone-related peptide (PTHrP) is the predominant cause of malignancy-associated hypercalcemia. However, its prognostic utility is unclear. We aimed to determine the prognostic value of serum PTHrP levels in patients who had hypercalcemia associated with malignancy.

METHODS

In this prospective case series, we evaluated 76 patients with a diagnosis of cancer and hypercalcemia (serum calcium level >/=10.3 mg/dL on at least two occasions). PTHrP levels >/=1 pmol/L were considered elevated. We used multivariate Cox regression analysis to identify factors associated with mortality.

RESULTS

Fifty patients (66%) died during follow-up. In a multivariate analysis, higher pretreatment calcium levels and elevated PTHrP levels were associated with increased mortality, with effects of PTHrP varying by age (P = 0.03). Survival was associated with pretreatment calcium levels both in patients over 65 years of age (hazard ratio [HR] per mg/dL = 1.5; 95% confidence interval [CI]: 1.2 to 1.8; P <0.001) and in patients aged 65 years or less (HR = 1.3; 95% CI: 1.1 to 1.5; P = 0.003). Adjusted for pretreatment calcium levels, elevated PTHrP levels were associated with increased mortality in patients aged </=65 years (HR = 3.8; 95% CI: 1.6 to 8.8; P = 0.002), but not in older patients (HR = 0.7; 95% CI: 0.3 to 1.9; P = 0.51).

CONCLUSION

PTHrP is a useful prognostic factor in malignancy-associated hypercalcemia, at least in patients aged </=65 years.

Tumour induced hypercalcaemia: a case for active treatment

This paper reports a retrospective survey of the diagnosis, management and outcome of hypercalcaemia in patients admitted to a regional oncology centre over a 12-month period; 168 cases of tumour induced hypercalcaemia were identified. In 69 patients (41%) the presence of hypercalcaemia was not noted in the case records; in a further 15 patients (9%) a positive decision was made not to treat the condition, although some of these patients continued to receive other forms of active treatment. Of the remaining patients, 20 (12%) received intravenous fluids alone and 64 (38%) received bisphosphonate therapy. Of those patients with initial serum calcium > 3 mmol/l 71% were treated with bisphosphonates. Median survival from onset of hypercalcaemia was only 2 months, but in the bisphosphonate treated group, 98% experienced a fall in serum calcium within a week of treatment. We believe that the symptomatic relief associated with a fall in serum calcium justifies active management even in the face of a poor prognosis. A large proportion of cases of tumour induced hypercalcaemia remain undiagnosed or untreated and we believe that this deserves further attention.

Humoral hypercalcaemia in renal carcinoma due to parathyroid hormone related protein

Parathyroid hormone related protein (PTHRP) has been implicated in humoral hypercalcaemia of malignancy (HHM). We describe a patient with a renal carcinoma and hypercalcaemia, and for the first time have demonstrated a 4-fold PTHRP concentration gradient across a renal tumour bed. This provides further strong evidence that the primary tumour was the source of the PTHRP. The PTHRP 1-86 content of the tumour tissue was 4.8 ng/g, similar to that previously found in tumours associated with HHM. In PTHRP-secreting tumours, PTHRP may be a useful oncological marker after surgical resection.

Incidence of hypercalcemia in patients with malignancy referred to a comprehensive cancer center

BACKGROUND

Hypercalcemia is a serious and not infrequent complication of malignant diseases; precise information about the incidence of hypercalcemia is not readily available. The study was designed to determine the incidence of hypercalcemia in patients with cancer.

METHODS

Retrospective analysis was done of laboratory data from 7667 patients registered at M.D. Anderson Cancer Center for the first time during 1989 for whom serum calcium levels were determined during the first 2 months after registration.

RESULTS

Severe hypercalcemia (serum calcium level of more than 12.0 mg/100 ml) was present in 40 patients (0.52%); it occurred most often in patients with renal cell cancer (1.42%) and non-small cell lung cancer (1.03%). Less frequent diagnoses were multiple myeloma (0.79%), leukemia (0.63%), non-Hodgkin lymphoma (0.26%), and cancer of the gastrointestinal tract (0.20%). Moderate hypercalcemia (calcium levels of 10.8-12.0 mg/100 ml) was present in 48 patients (0.63%); it occurred most often in patients with renal cell cancer (3.30%) and multiple myeloma (2.38%). Less frequent diagnoses were non-small cell lung cancer (0.89%), non-Hodgkin lymphoma (0.79%), leukemia (0.63%), and cancer of the gastrointestinal tract (0.51%). The presence of hypercalcemia was associated with increased frequency of distant metastases, bone metastases, and increased mortality consistent with other studies of the prognostic effect of this complication.

CONCLUSIONS

Hypercalcemia may appear as a frequent complication in patients with cancer at some time during the course of their disease, but its incidence is relatively low.

Epidermal growth factor and its receptor: markers of--and targets for--chemoprevention of bladder cancer

Epidermal growth factor (EGF) is excreted in urine in high concentrations in a biologically active form. Several lines of evidence indicate that EGF plays a role in transitional cell carcinoma (TCC) development and growth. These include: (1) EGF in the normal urine of rats promotes chemically initiated TCC; (2) EGF in normal human urine stimulates the clonal growth of human TCC cells in vitro; (3) EGF stimulates the in vitro growth of human TCC cells, but not normal human urothelial cells; (4) the density and distribution of the EGF receptor (EGF-R) on human urothelial tissues permits significant access of premalignant, dysplastic, and malignant cells to EGF; and (5) the concentration of EGF in the voided urine of patients with TCC is reduced, implying that EGF may be "extracted" from urine by the greater number of EGF-Rs in patients with urothelial malignancy. Abnormal expression of the urothelial EGF-R and/or altered excretion of EGF may well precede overt evidence of TCC and thus may serve as markers of risk or exposure. Similarly, reversion of EGF-R expression or the return of excreted EGF to normal levels may provide a marker of response for preventive and therapeutic strategies. Interference with the EGF/EGF-R interaction through dietary or pharmacological manipulations of the urine, or via targeting strategies employing intravesical administration of conjugated toxins or isotopes is already being employed in experimental and clinical studies. These approaches offer promising new tools in the detection, monitoring, prevention, and management of early stage bladder cancer.