Overall Survival in Men With Bone Metastases From Castration-Resistant Prostate Cancer Treated With Bone-Targeting Radioisotopes: A Meta-analysis of Individual Patient Data From Randomized Clinical Trials.

Importance: Both α-emitting and ß-emitting bone-targeted radioisotopes (RIs) have been developed to treat men with metastatic castration-resistant prostate cancer (CRPC). Only 1 phase 3 randomized clinical trial has demonstrated an overall survival (OS) benefit from an α-emitting RI, radium 223 (223Ra), vs standard of care. Yet no head-to-head comparison has been done between α-emitting and ß-emitting RIs. Objective: To assess OS in men with bone metastases from CRPC treated with bone-targeted RIs and to compare the effects of α-emitting RIs with ß-emitting RIs. Data Sources: PubMed, Cochrane Library, ClinicalTrials.gov, and meeting proceedings between January 1993 and June 2013 were reviewed. Key terms included randomized trials, radioisotopes, radiopharmaceuticals, and prostate cancer. Data were collected, checked, and analyzed from February 2017 to October 2018. Study Selection: Selected trials included patients with prostate cancer, recruited more than 50 patients from January 1993 to June 2013, compared RI use with no RI use (placebo, external radiotherapy, or chemotherapy), and were randomized. Patients were diagnosed with histologically proven prostate cancer and disease progression after both surgical or chemical castration and have evidence of bone metastasis. Nine randomized clinical trials were identified as eligible, but 3 were excluded for insufficient data. Data Extraction and Synthesis: Individual patient data were requested for each eligible trial, and all data were checked with a standard procedure. The log-rank test stratified by trial was used to estimate hazard ratios (HRs), and a similar fixed-effects (FE) model was used to estimate odds ratios (ORs). The between-trial heterogeneity of treatment effects was evaluated by Cochran test and I2 and was accounted by a random-effects (RE) model. Main Outcomes and Measures: Overall survival; secondary outcomes were symptomatic skeletal event (SSE)-free survival and adverse events. Results: Based on 6 randomized clinical trials including 2081 patients, RI use was significantly associated with OS compared with no RI use (HR, 0.86; 95% CI, 0.77-0.95; P = .004) with high heterogeneity (χ25 = 24.46; P < .001; I2 = 80%), but this association disappeared when using an RE model (HR, 0.80; 95% CI, 0.61-1.06; P = .12; τ2 = 0.08). The heterogeneity is explained both by the type of RI and by the inclusion of 2 outlier trials that included 275 patients; the OS benefit was significantly higher with the α-emitting RI 223Ra (HR, 0.70; 95% CI, 0.58-0.83) but not significant with the ß-emitting RI strontium-89 (HR, 0.96; 95% CI, 0.84-1.10) (P for interaction = .004). Excluding the outlier trials led to an overall HR of 0.82 (95% CI, 0.73-0.92; P < .001) (between-trial heterogeneity: χ23 = 6.51; P = .09; I2 = 54%) using an FE model and an HR of 0.80 (95% CI, 0.65-0.99; P = .04; τ2 = 0.02) using an RE model. The HR for SSE-free survival was 0.81 (95% CI, 0.69-0.93; P = .004) (between-trial heterogeneity: χ23 = 6.71; P = .08; I2 = 55%) when using an FE model and was 0.76 (95% CI, 0.58-1.01; P = .06; τ2 = 0.04) when using an RE model. There were more hematological toxic effects with RI use compared with no RI use (OR, 1.48; 95% CI, 1.17-1.88; P = .001). Conclusions and Relevance: In metastatic CRPC, a significant improvement of OS and SSE-free survival was obtained with bone-targeted α-emitting but not ß-emitting RIs. Caution is necessary for generalizability of these results, given the between-trial heterogeneity.

Germline glutathione S-transferase variants in breast cancer: relation to diagnosis and cutaneous long-term adverse effects after two fractionation patterns of radiotherapy.

PURPOSE: To explore whether certain glutathione S-transferase (GST) polymorphisms are associated with an increased risk of breast cancer or the level of radiation-induced adverse effects after two fractionation patterns of adjuvant radiotherapy. METHODS AND MATERIALS: The prevalence of germline polymorphic variants in GSTM1, GSTP1, and GSTT1 was determined in 272 breast cancer patients and compared with that in a control group of 270 women from the general population with no known history of breast cancer. The genetic variants were determined using multiplex polymerase chain reaction followed by restriction enzyme fragment analysis. In 253 of the patients surveyed for radiotherapy-induced side effects after a median observation time of 13.7 years (range, 7-22.8 years), the genotypes were related to the long-term effects observed after two fractionation patterns (treatment A, 4.3 Gy in 10 fractions for 156 patients; and treatment B, 2.5 Gy in 20 fractions for 97; both administered within a 5-week period). RESULTS: None of the GST polymorphisms conferred an increased risk of breast cancer, either alone or in combination. Compared with treatment B, treatment A was followed by an increased level of moderate to severe radiation-induced side effects for all the endpoints studied (i.e., degree of telangiectasia, subcutaneous fibrosis and atrophy, lung fibrosis, costal fractures, and pleural thickening; p <0.001 for all endpoints). A significant association was found between the level of pleural thickening and the GSTP1 Ile105Val variant. CONCLUSION: The results of this study have illustrated the impact of hypofractionation on the level of adverse effects and indicated that the specific alleles of GSTP1, M1, and T1 studied here may be significant in determining the level of adverse effects after radiotherapy.

Basoluminal carcinoma: a new biologically and prognostically distinct entity between basal and luminal breast cancer.

PURPOSE: Breast carcinomas expressing basal epithelium cytokeratins constitute a tumor subgroup that is typically hormone receptor negative and shows a distinct gene expression profile. Based on variable basal cytokeratin immunostaining patterns, we hypothesized that the "basal phenotype" tumor group may comprise more than one biological entity. EXPERIMENTAL DESIGN: Basal cytokeratins 5 and 14 (CK5/14) were stained by immunohistochemistry and the percentage of positive cells was defined by image analysis. The results thus obtained were compared with clinicopathologic characteristics and relapse-free survival. RESULTS: Of the 506 breast tumors, 53 (10.5%) showed immunoreactivity for CK5/14. Basal cytokeratin expression showed up as two microscopically distinguishable subtypes, i.e., a uniformly positive type ("basal") and a partially positive type ("basoluminal") often displaying a checkerboard-type intratumoral heterogeneity. These subgroups could also be separated with a third basal cytokeratin (CK17, P < 0.0001). Both basal and basoluminal subtypes were hormone receptor negative and of high grade, but differed with respect to the Ki-67 labeling index (P = 0.0014), vimentin (P = 0.005), and c-kit (P = 0.02), which were more frequently expressed in basal than in basoluminal tumors. In contrast, the amplification of HER-2 was found almost exclusively in the basoluminal subgroup (P = 0.009). Compared with the basal tumors, basoluminal tumors associated with significantly shorter relapse-free survival (P = 0.01), which was not explained by their more frequent HER-2 amplification. CONCLUSIONS: We conclude that the intratumoral heterogeneity in basal cytokeratin expression can be used to define two distinct breast cancer subtypes, basal and basoluminal, with distinctive features related to proliferation activity, oncogene and biomarker status, and patient survival.

Effects of exemestane administered for 2 years versus placebo on bone mineral density, bone biomarkers, and plasma lipids in patients with surgically resected early breast cancer.

PURPOSE: To evaluate potential detrimental effects of exemestane on bone and lipid metabolism. PATIENTS AND METHODS: Postmenopausal women with early breast cancer were randomly assigned to exemestane 25 mg daily or placebo for 2 years in a double-blind setting. Primary objective was to evaluate the effect of exemestane on bone mineral density. Secondary objectives were effects on bone biomarkers, plasma lipids, coagulation factors, and homocysteine. Planned size was 128 patients. RESULTS: One hundred forty-seven patients were enrolled. All patients completed their 24-month visit except for those discontinuing treatment at an earlier stage. The mean annual rate of bone mineral density loss was 2.17% v 1.84% in the lumbar spine (P = .568) and 2.72% v 1.48% in the femoral neck (P = .024) in the exemestane and placebo arm, respectively. The mean change in T-score after 2 years was -0.21 for exemestane and -0.11 on placebo in the hip, and -0.30 and -0.21, respectively, in the lumbar spine. Exemestane significantly increased serum level and urinary excretion of bone resorption, but also bone formation markers. Except for a modest reduction in high-density lipoprotein cholesterol (P < .001) and apolipoprotein A1 (P = .004), exemestane had no major effect on lipid profile, homocysteine levels, or coagulation parameters. CONCLUSION: Exemestane modestly enhanced bone loss from the femoral neck without significant influence on lumbar bone loss. Except for a 6% to 9% drop in plasma high-density lipoprotein cholesterol, no major effects on serum lipids, coagulation factors, or homocysteine were recorded. Bone mineral density should be assessed according to the US Preventive Services Task Force guidelines.

Quality of life in women with breast cancer during the first year after random assignment to adjuvant treatment with marrow-supported high-dose chemotherapy with cyclophosphamide, thiotepa, and carboplatin or tailored therapy with Fluorouracil, epirubicin, and cyclophosphamide: Scandinavian Breast Group Study 9401.

PURPOSE: To compare, in high-risk breast cancer patients, the effects on health-related quality of life (HRQoL) of two adjuvant treatments. Treatments were compared at eight points during the first year after random assignment to treatment with tailored fluorouracil, epirubicin, and cyclophosphamide (FEC) therapy for nine courses versus induction FEC therapy for three courses followed by high-dose chemotherapy with cyclophosphamide, thiotepa, and carboplatin (CTCb) supported by peripheral-blood stem cells. PATIENTS AND METHODS: From March 1994 to March 1998, 525 breast cancer patients (estimated relapse risk > 70% within 5 years with standard therapy) were included in the Scandinavian Breast Group 9401 study. HRQoL evaluation, using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ)-C30 and EORTC Breast Cancer Module-23, included 408 of 446 eligible patients in Finland, Norway, and Sweden. RESULTS: Eighty-four percent to 95% of the patients completed questionnaires at eight points of assessment. Nostatistically significant overall differences were found between the tailored FEC group and the CTCb group for any of the HRQoL variables. Statistically significant differences over time were found for all HRQoL variables. HRQoL in the CTCb group demonstrated a steeper decrease, but a faster recovery than in the tailored FEC group. Emotional functioning improved with increased time from randomization. Higher levels of problems in body image and arm symptoms were reported in the tailored FEC group compared with the CTCb group. Sexual functioning and satisfaction were impaired during the study period. CONCLUSION: Both treatments had a negative influence on HRQoL during the treatment period. Despite the aggressive therapies, the patient's HRQoL returned to levels found at inclusion on most variables.

Role of strontium-89 as adjuvant to palliative external beam radiotherapy is questionable: results of a double-blind randomized study.

PURPOSE: To explore the efficacy of adjuvant (89)Sr applied with external beam radiotherapy (EBRT) to treat bone metastases. METHODS AND MATERIALS: Ninety-five patients were randomized to (89)Sr (Arm A) or saline (Arm B) on Day 1 of EBRT to demonstrate a reduction in 3-month physician-assessed subjective progression from 70% to 45%. RESULTS: At 3 and 6 months, no difference between treatment arms was observed in the progression rate. At 3 months, the physician-assessed response rate for all patients was 25%, with 46% of the patients progressing. The pretreatment use of opiates was independently associated with short progression-free survival. On the basis of the quality-of-life assessments, pain relief occurred in 50% of patients and 32% experienced improvement in global quality of life, without impact from (89)Sr. Differences were observed between the physician evaluation of radiotherapy efficacy and the patient assessment. In Arm A, serum alkaline phosphatase, but not serum prostate-specific antigen, decreased during the first 3 months after treatment. CONCLUSION: (89)Sr, adjuvant to ERBT, does not seem to reduce the number of patients with subjective progression at 3 months. Patients should be referred for palliative RT before their bone pain requires high doses of opiates. In radiotherapy trials, the evaluation of pain and pain relief remains problematic because of the confounding use of analgesics.

Pharmacokinetic profile of intramuscular fulvestrant in advanced breast cancer.

OBJECTIVE: To characterise the pharmacokinetics of a long-acting formulation of fulvestrant following intramuscular administration of single and multiple doses. STUDY DESIGN: Pharmacokinetic investigations of single and multiple doses of fulvestrant were conducted within two global phase III efficacy studies that compared intramuscular fulvestrant with oral anastrozole in postmenopausal women with hormone-sensitive advanced breast cancer (study 0020, conducted in Europe, Australia and South Africa, and study 0021, conducted in North America). METHODS: Patients received once-monthly intramuscular injections of fulvestrant 250 mg (1 x 5 mL for < or =21 months in study 0020; 2 x 2.5 mL for < or =30 months in study 0021). Serial blood samples were collected for the first 28 days after the initial dose and immediately prior to all subsequent monthly doses. Plasma fulvestrant concentrations were determined by high-performance liquid chromatography-tandem mass spectrometry. PATIENTS: Twenty-six (study 0020) and 193 (study 0021) postmenopausal women, comprising the pharmacokinetic subgroups of the phase III efficacy trials, were studied. Patients had shown disease progression or recurrence following previous hormonal therapy for advanced disease or had relapsed after adjuvant endocrine therapy with a nonsteroidal antiestrogen. OUTCOME MEASURES AND RESULTS: For single-dose fulvestrant 250 mg, area under the concentration-time curve from time zero to 28 days (AUC(28)), maximum observed plasma concentration (C(max)), minimum observed plasma concentration at 28 days (C(min)) and time to maximum plasma concentration (t(max)) were determined. For multiple-dose fulvestrant 250 mg once monthly, steady-state trough concentrations (C(trough)) were determined. Plasma fulvestrant concentrations reached a peak at a median of 7 days (range 2-8 days) postdose, and declined biexponentially with a slower phase commencing approximately 2-3 weeks postdose. Intersubject variability in C(max) and AUC(28) was approximately 6-fold and 4-fold, respectively. Mean parameters for single-dose fulvestrant were: AUC(28), 148 microg. day/L; C(max), 8.2 microg/L; C(min), 2.6 microg/L; t(max), 7.0 days. Geometric mean C(trough) increased from 2.57 to 6.15 microg/L (study 0020) and from 2.38 to 6.52 microg/L (study 0021) over the first 6 months, reaching steady-state concentrations of approximately 6-7 microg/L (study 0020) or 9 microg/L (study 0021). Preliminary pharmacokinetic analysis, using a naive pooled data approach, suggests that observed single- and multiple-dose plasma profiles can be adequately described with a two-compartment kinetic model. Model-generated steady-state AUC(28) values were approximately 300 microg. day/L. CONCLUSIONS: The intramuscular formulation of fulvestrant displays predictable kinetics and approximately 2-fold accumulation on administration once monthly. At the proposed therapeutic dosage (250 mg once monthly), plasma fulvestrant concentrations are maintained within a narrow range throughout the administration interval, thus ensuring stable systemic drug exposure during long-term treatment.

Topoisomerase IIalpha gene amplification predicts favorable treatment response to tailored and dose-escalated anthracycline-based adjuvant chemotherapy in HER-2/neu-amplified breast cancer: Scandinavian Breast Group Trial 9401.

PURPOSE: Amplification of the HER-2/neu and topoisomerase IIalpha (TOP2A) genes has been linked to the effects of anthracyclines. Their role in predicting the outcome of anthracycline-based adjuvant chemotherapy for breast cancer patients has remained controversial. PATIENTS AND METHODS: The present substudy of the Scandinavian Breast Group trial 9401, in which an epirubicin-based regimen (nine courses of tailored and dose-escalated fluorouracil, epirubicin, and cyclophosphamide [FEC]) was compared with three or four courses of standard FEC followed by bone marrow-supported high-dose chemotherapy (cyclophosphamide, thiotepa, and carboplatin), included high-risk breast cancer patients (with eight or more positive axillary lymph nodes or at least five nodes with additional poor prognostic indicators). Amplification of HER-2/neu was determined retrospectively in paraffin-embedded tumor tissue sections by chromogenic in situ hybridization. TOP2A was tested only in HER-2/neu-amplified tumors. RESULTS: HER-2/neu amplification alone, which was present in 32.7% of the tumors, was a strong prognostic factor for short relapse-free (P = .0034) and overall survival (P = .0008) but showed no direct association with treatment assignment. TOP2A coamplification, which was present in 37% of HER-2/neu-amplified tumors, was associated with better relapse-free survival in patients treated with tailored and dose-escalated FEC (hazard ratio [HR] = 0.45; P = .049). A statistical multivariate Cox's regression analysis confirmed the predictive significance of TOP2A coamplification (HR = 0.30; P = .020) in HER-2/neu-amplified tumors. There was no such association in patients with HER-2/neu-amplified tumors without TOP2A gene amplification. CONCLUSION: Coamplification of HER-2/neu and TOP2A may define a subgroup of high-risk breast cancer patients who benefit from individually tailored and dose-escalated adjuvant anthracyclines.

Monitoring of disseminated tumor cells in bone marrow in high-risk breast cancer patients treated with high-dose chemotherapy.

The present study aimed to investigate the clinical relevance of disseminated tumor cells (DTC) in breast cancer patients before and after high-dose adjuvant chemotherapy with or without progenitor stem-cell support. One hundred and eighteen high-risk stage II breast cancer patients entering the Scandinavian Study Group multicenter trial were randomized to 9 cycles of tailored and dose-escalated FEC (5-fluorouracil, epirubicin, cyclophosphamide) or 3 cycles of standard FEC followed by high-dose chemotherapy. Bone marrow (BM) samples at diagnosis and 6 months after completion of chemotherapy were assessed for the presence of cytokeratin positive (CK+) cells. Before treatment, 29% of the patients were CK+ (21% in the dose-escalated group and 36% in the high-dose-group). Six months after treatment, 17% of the patients were CK+ (17 and 16% respectively). Of the 95 patients who were evaluated 6 months after treatment, 60% were consistently CK-. CK+ cells in BM was evaluated as a prognostic and predictive marker and compared to other defined prognostic factors of the primary tumor. Monitoring BM changes at the time of diagnosis and 6 months posttreatment is an independent predictive factor for breast-cancer-specific survival (BCS) (p = 0.001). Those who have consistent CK negative (-) BM findings constitute a group of patients with good prognosis. Our results suggest that changes in CK+ cells in BM before and after chemotherapy can be used clinically as a surrogate maker to predict outcome in breast cancer patients.