Comprehensive analysis integrating both clinicopathological and gene expression data in more than 1,500 samples: Proliferation captured by gene expression grade index appears to be the strongest prognostic factor in breast cancer (BC)

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Background: Although, the development of high-throughput gene expression technologies has allowed the identification of several “molecular signatures” predicting clinical outcome, no attempt has been made yet to perform a comprehensive analysis integrating both clinicopathological, and gene expression data. Here, we aim to elucidate the relationship between clinical parameters and tumor markers, with gene expression patterns and their interaction with prognosis. Methods: We analyzed gene expression and clinical data from several published studies, including more than 1500 BC patients. We developed several gene expression indices associated with different biological stages of disease characterized by the expression of hormone receptors, HER2 amplification, p53 mutation, angiogenesis, tumor invasion and proliferation. Multivariable analyses were used to characterize the dependency patterns between these indices and their impact on survival. Results: Estrogen receptor (ER) and HER2 indices were the most prominent discriminators dichotomizing tumor samples into two main subsets in agreement with the previously proposed BC subtypes. Tumor proliferation, assessed by our previously reported gene expression index (GGI), was the most strongly associated with prognosis (HR 2.29, CI 1.88–2.78, p<0.0001). Almost all ER- and HER2+ tumors were associated with high GGI scores. In contrast, ER+ and HER2- tumors showed a whole range of GGI values. Within the high proliferation subset, ER- and HER2+ indices did not have any prognostic value. Similar results were found with relation to p53 mutation index. Nodal status and tumor size, which essentially measure the duration of disease, retained prognostic value in addition to proliferation. Conclusions: Proliferation captured by the GGI appears to be a key biological factor, downstream of ER, HER2 and p53. Although understanding the upstream factors is important for advancing biological knowledge and therapeutic interventions, GGI seems to be the most important factor predicting clinical outcome in BC and deserves consideration as stratification factor in clinical trials.

No significant financial relationships to disclose.

Gene expression profiling in breast cancer: understanding the molecular basis of histologic grade to improve prognosis

BACKGROUND

Histologic grade in breast cancer provides clinically important prognostic information. However, 30%-60% of tumors are classified as histologic grade 2. This grade is associated with an intermediate risk of recurrence and is thus not informative for clinical decision making. We examined whether histologic grade was associated with gene expression profiles of breast cancers and whether such profiles could be used to improve histologic grading.

METHODS

We analyzed microarray data from 189 invasive breast carcinomas and from three published gene expression datasets from breast carcinomas. We identified differentially expressed genes in a training set of 64 estrogen receptor (ER)-positive tumor samples by comparing expression profiles between histologic grade 3 tumors and histologic grade 1 tumors and used the expression of these genes to define the gene expression grade index. Data from 597 independent tumors were used to evaluate the association between relapse-free survival and the gene expression grade index in a Kaplan-Meier analysis. All statistical tests were two-sided.

RESULTS

We identified 97 genes in our training set that were associated with histologic grade; most of these genes were involved in cell cycle regulation and proliferation. In validation datasets, the gene expression grade index was strongly associated with histologic grade 1 and 3 status; however, among histologic grade 2 tumors, the index spanned the values for histologic grade 1-3 tumors. Among patients with histologic grade 2 tumors, a high gene expression grade index was associated with a higher risk of recurrence than a low gene expression grade index (hazard ratio = 3.61, 95% confidence interval = 2.25 to 5.78; P < .001, log-rank test).

CONCLUSIONS

Gene expression grade index appeared to reclassify patients with histologic grade 2 tumors into two groups with high versus low risks of recurrence. This approach may improve the accuracy of tumor grading and thus its prognostic value.

Obesity and outcomes in premenopausal and postmenopausal breast cancer

PURPOSE

Obesity is associated with adverse outcomes in postmenopausal women with breast cancer. In premenopausal women, the association is less clear.

METHODS

A population-based sample of 1,360 Australian women with breast cancer before the age of 60 years, 47% diagnosed before age 40, and 74% premenopausal, was studied prospectively for a median of 5 years (range, 0.2-10.8 years). Obesity was defined as a body mass index of > or =30 kg/m2. The hazard ratio (HR) for adverse clinical outcome associated with obesity was estimated using Cox proportional hazard survival models.

RESULTS

Obesity increased with age (P < 0.001) and was associated with increased breast cancer recurrence (P = 0.02) and death (P = 0.06), larger tumors (P = 0.002), and more involved axillary nodes (P = 0.003) but not with hormone receptor status (P > or = 0.6) or with first cycle adjuvant chemotherapy dose reductions (P = 0.1). Adjusting for number of axillary nodes, age at diagnosis, tumor size, grade, and hormone receptor status, obese women of all ages were more likely than nonobese women to have disease recurrence [HR, 1.57; 95% confidence interval (95% CI), 1.11-2.22; P = 0.02] and to die from any cause during follow-up (HR, 1.56; 95% CI, 1.01-2.40; P = 0.05). In premenopausal women, the adjusted HRs were 1.50 (95% CI, 1.00-2.26; P = 0.06) and 1.71 (95% CI, 1.05-2.77; P = 0.04), respectively.

CONCLUSIONS

Obesity is independently associated with poorer outcomes in premenopausal women, as it is in postmenopausal women, and this is not entirely explained by differences in tumor size or nodal status. Given the high and increasing prevalence of obesity in western countries, more research on improving the treatment of obese breast cancer patients is warranted.

Oxaliplatin combined with infusional 5-fluorouracil and concomitant radiotherapy in inoperable and metastatic rectal cancer: a phase I trial

The aim of this study was to define the recommended dose of oxaliplatin when combined with infusional 5-fluorouracil (5-FU) and concurrent pelvic radiotherapy. Eligible patients had inoperable rectal cancer, or symptomatic primary rectal cancer with metastasis. Oxaliplatin was given on day 1 of weeks 1, 3 and 5 of radiotherapy. Dose level 1 was oxaliplatin 70 mg m(-2) with 5-FU 200 mg m(-2) day(-1) continuous infusion 96 h week(-1). On dose level 2, the oxaliplatin dose was increased to 85 mg m(-2). On dose level 3, the duration of the 5-FU was increased to 168 h per week. Pelvic radiotherapy was 45 Gray (Gy) in 25 fractions over 5 weeks with a boost of 5.4 Gy. Fluorine-18 fluoro deoxyglucose and Fluorine-18 fluoro misonidazole positron emission tomography (FDG-PET and FMISO-PET) were used to assess metabolic tumour response and hypoxia. In all, 16 patients were accrued. Dose-limiting toxicities occurred in one patient at level 2 (grade 3 chest infection), and two patients at level 3 (grade 3 diarrhoea). Dose level 2 was declared the recommended dose level. FDG-PET imaging showed metabolic responses in 11 of the 12 primary tumours assessed. Four of six tumours had detectable hypoxia on FMISO-PET scans. The addition of oxaliplatin to infusional 5-FU chemoradiotherapy was feasible and generally well tolerated. For future trials, oxaliplatin 85 mg m(-2) and 5-FU 200 mg m(-2) day(-1) continuous infusion 96 h week(-1) is the recommended dose when combined with 50.4 Gy of pelvic radiotherapy.

Towards evidence-based use of serum tumour marker requests: an audit of use in a tertiary hospital

BACKGROUND

Serum tumour markers (TM) are often measured in hospital patients. The reasons for their use and their benefits with regards to earlier cancer diagnosis and patient management are not known.

AIMS

To identify the patterns of TM use in a tertiary hospital and to determine the usefulness and appropriateness of requests in this setting.

METHODS

A cross-sectional, retrospective study of TM ordered over a 3-month period was conducted. Data were obtained from patient records. CA-125, CA 15-3, CA 19-9, carcinoembryonic antigen (CEA), and alpha-fetoprotein (AFP) were studied. Prostate specific antigen was not separately investigated. The reasons for ordering, usefulness and appropriateness of use were defined prior to analysis.

RESULTS

A total of 476 TM was ordered in 373 patients. One hundred and six (22%) of all results were abnormal by laboratory criteria. AFP was the most popular test ordered. Forty-seven per cent of patients had no cancer diagnosis. Oncological units (ONC) ordered 27% of tests. The most popular reasons for TM ordering were for screening (36%) followed by diagnostic aid (19%). ONC units ordered TM mainly for monitoring disease status, as opposed to non-ONC units who ordered TM usually for diagnostic aid. TM were deemed appropriately ordered in 69% of cases. Twenty-nine per cent of TM were helpful in patient management. Only four results (<1%) aided in diagnosis.

CONCLUSIONS

The reasons and appropriateness of TM use varied depending on the specialization of the requesting clinician. The current serum TM are most useful as aids in cancer patients, rather than for diagnosis (P <0.0001). Apart from AFP, these TM seem to have limited use in the general medical, non-oncological patients. Guidelines for their use in this setting are needed.

Breast cancer gene expression profiling: clinical trial and practice implications

The advent of high-throughput array-based technology and the sequencing of the human genome has provided the opportunity to begin comprehensive molecular and genetic profiling of cancers. Such efforts have, in a limited time, given us new insights into breast cancer biology and confirmed that the disease is considerably more heterogeneous than can be predicted by traditional histopathological methods. The estrogen receptor has been found to be the most dominant factor influencing the molecular composition of breast cancer and, in addition, novel subgroups of breast cancer with differing clinical outcomes have been observed. These may have substantial management implications for breast cancer patients and facilitate individualized rather than empirical oncological prescription. Furthermore, new methods of prognostic classification have been developed using array technology. The challenges ahead lie in refining the use of the technology, proper validation of discoveries, and the large-scale collaborative efforts necessary for the incorporation of genomic knowledge into the design and conduct of clinical trials. This will lead, ultimately, to the application of user-friendly tools derived from this technology to everyday patient care.

Glomerulosclerosis: A paraneoplastic phenomenon?

Glomerulosclerosis is not classically considered a paraneoplastic glomerular lesion. Focal and segmental glomerulosclerosis (FSGS) has rarely been reported in association with solid tumours. We report three cases of FSGS and an additional case of collapsing glomerulosclerosis in patients presenting with nephrotic syndrome and malignancy.

Challenges in breast cancer clinical trial design in the postgenomic era

PURPOSE OF REVIEW

Clinical trials in breast cancer (BC) have seldom taken into consideration molecular heterogeneity, because most have been performed in unselected populations. Hence, their results provide an estimated average benefit for the entire BC population, which may not always be translated to subsets of patients with certain characteristics, let alone to individual patients. Further understanding and acknowledgment of heterogeneity is vital for the development of individualized therapy in BC. New approaches are needed for trial design, patient selection, and choice of endpoints (including surrogate markers). The neoadjuvant setting presents a unique opportunity to test new concepts in a previously untreated patient population, because they may yield preliminary answers in a shorter time than that required in adjuvant trials.

RECENT FINDINGS

The importance of patient selection in the development of targeted agents is exemplified by trastuzumab in BC and of gefitinib in lung cancer. Ongoing innovative trials that investigate biologic hypotheses include the BIG-EORTC p53, TOP and FRAGRANCE trials (which study predictive factors for response), and the NNBC-3 and MINDACT trials (which study prognostic factors).

SUMMARY

There is an urgent need to break from traditional clinical development and to incorporate new molecular knowledge and translational research in the design of clinical trials. The success of new approaches in BC research critically depends on well-conducted translational research linked to prospective clinical trials, and international collaboration, bringing together human and technological resources.

Castleman's disease and HIV infection in Australia

OBJECTIVES

To describe, retrospectively, the Australian experience of multi-centric Castleman's disease (MCD) in the setting of HIV infection, specifically with the advent of HAART, and newer chemotherapeutic agents.

PATIENTS AND METHODS

HIV-infected patients diagnosed with MCD since 1994, were identified from three major HIV treatment centres in Australia. Demographic and disease characteristic variables were collated by the National Centre in HIV Epidemiology and Clinical Research.

RESULTS

Eleven patients were identified with MCD. Medial follow up was 46 (18-57) months. All had CD4 cell counts less than 500 cells/microL. All but one patient was receiving HAART at the time of diagnosis. Nine of the 11 patients had Kaposi's sarcoma (KS) and two patients also developed non-Hodgkin's Lymphoma (NHL). All patients received chemotherapy for MCD. The response rate from Chemotherapy was 64%. Only two patients achieved sustained remissions. The median survival was 21.9 (1-52) months. The mortality was 45% from MCD and its related complications.

CONCLUSION

MCD in HIV infected patients is a rare and life-threatening disorder. There is limited recent information on optimal treatment for MCD. MCD in our series appeared to be a chemo-responsive disease. In our experience, treatment with liposomal anthracycline was associated with good response rates and acceptable toxicity in several patients, and therefore merits further exploration to establish its role. Treatment in the future may concentrate on novel agents such as anti-interleukin 6, anti-CD20 antibodies, thalidomide and viral ablation.

A randomized cross-over trial to determine the effect of Cremophor EL on the pharmacodynamics and pharmacokinetics of carboplatin chemotherapy

PURPOSE

Paclitaxel, when combined with carboplatin, exhibits a platelet-sparing effect. Paclitaxel is formulated in Cremophor EL (CrEL), which has been shown in preclinical models to reduce haematological toxicity from radiotherapy and chemotherapy. We sought to determine the effect of a 3-h infusion of 20 ml/m2 (equivalent to 175 mg/m2 paclitaxel) CrEL on myelosuppression following carboplatin chemotherapy, and the effect of CrEL on carboplatin pharmacokinetics.

METHODS

A total of 16 patients with locally advanced or metastatic cancer were randomized to receive either CrEL or saline over 3 h prior to carboplatin (area under the curve, AUC, 5-7). Each patient was subsequently crossed over to the other treatment. Blood samples were collected at selected time-points for estimation of platinum AUC and 24-h platinum levels. Full blood counts were obtained three times per week.

RESULTS

Of the 16 patients randomized, 15 were evaluable. Myelosuppression was measured by percentage fall at nadir and nadir levels. No significant differences were obtained when comparing CrEL and saline with respect to the above end-points after adjusting for multiple testing. There was no evidence to indicate that CrEL altered the pharmacokinetics of carboplatin.

CONCLUSION

CrEL at this dose and schedule does not appear to be a major contributory factor to the platelet-sparing effect of paclitaxel when combined with carboplatin, nor does it alter the pharmacokinetics of carboplatin.

Prevalence of malnutrition assessed by bioimpedance analysis and anthropometry in children on peritoneal dialysis

OBJECTIVE

To evaluate the sensitivity of anthropometry and bioelectrical impedance analysis (BIA) in detecting alterations in body composition of children treated with peritoneal dialysis (PD), and to determine the prevalence of malnutrition in this population, in short- and long-term PD duration, using anthropometric and BIA-derived indices.

PATIENTS

Eighteen children treated with automated PD (11 males, 7 females; mean age 8.7 +/- 4.7 years).

DESIGN

Eighteen patients were studied using anthropometry and BIA at the start (t0) and after 6 months (t1) of PD, 15 of these patients at 12 months (t2), and 8 at 24 months (t3) of PD. Midarm muscle circumference (MAMC), arm muscle area (AMA), and arm fat area (AFA) were calculated from anthropometric measures according to Frisancho (FrisanchoAR. New norms of upper limb fat and muscle areas for assessment of nutritional status. Am J Clin Nutr 1981; 34:2540-5.). The bioelectrical measures of resistance (R) and reactance (Xc) were obtained directly from the impedance signal; phase angle (PA) and distance (D) were calculated using mathematical formulas. Nutritional status was assessed by anthropometric measurements and BIA-derived indices, expressed as standard deviation scores (SDS), and by a score system based on BIA and anthropometric parameters. The percentage of children with values of anthropometric and BIA-derived indices below the 3rd percentile or between the 3rd and 25th percentiles, and the percentage of children with scores of 7-12 and 4-6 were calculated in order to detect patients with severe or moderate derangement of nutritional status.

RESULTS

The mean SDS values of Xc, PA, and D significantly improved (p = 0.05, p = 0.001, p = 0.02) during the first 6 months of PD and remained almost stable during the following months. The SDS values of the anthropometric indices were less compromised than those of the BIA-derived indices, particularly at the start of dialysis. By 6 months, the percentages of children with values of BIA and anthropometric indices below the 3rd percentile had decreased. The percentages of patients with moderate and severe derangement of BIA and anthropometric indices remained substantially unchanged after 12 months. However, at 24 months, the percentage of patients with moderate derangement of BIA indices increased. All these findings were confirmed by the nutritional score system.

CONCLUSION

BIA is more sensitive than anthropometry in detecting alterations in body composition of children on PD. The prevalence of malnutrition, high at the commencement of PD, decreases during the first year of treatment but not over the long term.

Models to assess nitrogen losses in pediatric patients on chronic peritoneal dialysis

To develop models to estimate nitrogen (N) losses of children on chronic peritoneal dialysis (CPD) from easily measurable indexes and laboratory tests, we measured the N content and all nitrogenous compounds in dialysate (D), urine (U), and feces over 3 days in 19 pediatric patients on CPD. Total measured N losses (TNm) were 5.56+/-2.26 g/day (69.9+/-11.1% in dialysate, 16.3+/-10.6% in urine, and 13.6+/-4.6% in feces). Correlation coefficients between measured dialysate and urinary N losses and the single nitrogenous compounds indicated values of over 0.9 only for urea in dialysate and urine; fecal N losses correlated well with body surface area (BSA). Taking into account these correlations, we developed a univariate additive model and three multivariate models to predict total estimated N losses (TNe). The best prediction of TNm was obtained with model 3, which considered not only urea output in dialysate and urine but also dialysate protein loss and BSA: TNe (g/day)=0.03+/-1.138 UN urea+0.99 DN urea+1.18 BSA+0.965 DN protein. A confirmatory analysis performed on a second group of 23 pediatric patients on CPD, using all four models, showed a higher percentage of studies with a relative difference between TNm and TNe less than 10% for model 3 than for the other models. Thus, N losses of pediatric patients on CPD can be estimated from measured urea and protein losses in dialysate and urea loss in urine, together with BSA.

Study of impulse-control disorders among alcohol-dependent patients

BACKGROUND

Impulse-control disorders (ICDs) include intermittent explosive disorder, kleptomania, trichotillomania, pyromania, and pathological gambling. Several studies have suggested that the incidence of pathological gambling is substantially higher in alcoholics than in the general population. The rate of co-occurrence of other ICDs and alcohol dependence has never been systematically investigated. In our study, we assessed the frequency of all ICDs in a population of alcohol-dependent patients. We also examined the possibility that the presence of an ICD can correspond to earlier onset and more severe forms of alcoholism, which have a greater association with antisocial personality.

METHOD

All patients hospitalized at our psychiatric unit for detoxification between January and August 1997 met DSM-IV criteria for alcohol dependence and were included in this study. Diagnosis of alcohol dependence was confirmed with the Mini-International Neuropsychiatric Interview. ICDs were investigated using the Minnesota Impulsive Disorders Interview. All patients completed the Michigan Alcoholism Screening Test.

RESULTS

Among the 79 patients included in the study, 30 (38.0%) met criteria for an ICD. Included in the study were 19 cases of intermittent explosive disorder, 7 cases of pathological gambling, 3 cases of kleptomania, and 1 case of trichotillomania. Patients with co-occurring ICDs were significantly younger than patients without an ICD (mean age = 40.7 vs. 44.5 years; p = .03). Patients with co-occurring pathological gambling were significantly younger at the onset of alcohol dependence than patients without ICDs (mean age = 19.5 vs. 25.9 years; p = .0008). Pathological gamblers had significantly longer duration of alcohol dependence compared with patients without ICDs (26.0 vs. 17.9 years; p = .02). Patients with co-occurring intermittent explosive disorder had the shortest duration of alcohol dependence of all patients (9.9 years). Prevalence of antisocial personality disorder was no different in patients with or without co-occurring ICDs.

CONCLUSION

Thirty-eight percent of the alcohol-dependent patients studied presented with an ICD. Patients with ICDs were younger than those without an ICD. The presence of an ICD was not associated with a specific form of alcohol dependence or with antisocial personality. Co-occurrence of pathological gambling, however, was associated with lower age at onset of alcohol dependence, a higher number of detoxifications, and a longer duration of alcohol dependence than was absence of an ICD.

Dietary prescription based on estimated nitrogen balance during peritoneal dialysis

Protein and energy requirements of children on automated peritoneal dialysis (APD) have still not been sufficiently well defined, although their adequacy is important to maintain a positive nitrogen (N) balance and prevent malnutrition. We carried out 42 studies to estimate N balance in 31 children over 3 years on APD for 19.8+/-15.7 months. Twenty metabolic studies were performed in patients dialysed for less than 1 year (7.2+/-3.3 months) and 22 in patients treated for more than 1 year (31.3+/-13.6 months). The mean estimated N balance of all metabolic studies was 57.5+/-62.8 mg/kg per day. In only 21 of 42 studies was N balance estimated to be over 50 mg/kg per day, which is considered adequate to meet N requirements for all metabolic needs and growth of uremic children. Estimated N balance correlated significantly with dietary protein intake (r=0.671, P=0.0001) and total energy intake (r=0.489, P=0.001). Using the equations of correlation, the values of dietary protein intake [=144% recommended dietary allowance (RDA)] and total energy intake (89% RDA) required to obtain an estimated N balance >50 mg/kg per day were calculated. Significantly lower estimated N balance values were obtained in the studies performed on patients on APD for over 1 year (36.09+/-54.02 mg/kg per day) than in patients treated for less than 1 year (81.11+/-64.70 mg/kg per day). In conclusion, based on the values of estimated N balance, we were able to establish adequate dietary protein and energy requirements for children on APD.

Impulse-control disorders in alcoholics are related to sensation seeking and not to impulsivity

Impulse-control disorders (ICD) include intermittent explosive disorder, kleptomania, trichotillomania, pyromania and pathological gambling. Several studies have suggested that the incidence of pathological gambling and impulsive violent behavior is substantially higher in alcohol-dependent patients than in the general population. The association between ICD and alcoholism, as well as personality characteristics such as sensation seeking and impulsivity, has never been systematically studied. The present study compared the levels of impulsivity and sensation seeking in age- and sex-matched groups of alcohol-dependent patients with concomitant ICD (ICD+, n = 30), alcohol-dependent patients without ICD (ICD-; n = 30) and control subjects (n = 30). All the alcohol-dependent patients (ICD+ and ICD-) were hospitalized for alcohol detoxification. Diagnoses of ICD were based on DSM-IV criteria and the Minnesota Impulsive Disorders Interview. All patients completed the Zuckerman Sensation-Seeking Scale (SSS) and the Barratt Impulsiveness Rating Scale (BIS). Mean scores on the SSS general factor, the SSS disinhibition subscale, and the SSS experience-seeking scale were significantly higher in ICD+ patients than in either ICD- patients or control subjects. By contrast, total scores and subscale scores on the BIS showed no significant differences among the three groups. Thus, it appears that measures of sensation seeking, rather than impulsivity, are relevant in distinguishing between alcohol-dependent patients with and without concomitant impulse control disorders.

Short-term anabolic effects of recombinant human growth hormone in young patients with a renal transplant

Renal-transplanted children may present stunted growth, negative nitrogen balance (Nb), and alterations in body composition. Recombinant human growth hormone (rhGH) is a potent anabolic agent which improves nutritional status and Nb. In renal-transplanted children, rhGH increases growth velocity but its effect on nutritional status has not been reported. We evaluated the effect of 6 months of rhGH treatment on Nb, urea nitrogen appearance (UNA), anthropometric indexes, and growth velocity in 14 pediatric patients with a renal transplant. Nb improved significantly (P = 0.02) and was accompanied by a decrease of UNA. A significant improvement was observed also in mid-arm muscle circumference (P = 0.002), arm muscle are (P = 0.001), and arm fat are (P = 0.017). Growth velocity increased in prepubertal patients (P = 0.003). Creatinine clearance and the number of rejection episodes were not affected by rhGH treatment. In conclusion, short-term administration of rhGH improves Nb and UNA as well as the main indexes of body composition.