The use of canines in the detection of human cancers.

OBJECTIVES: To determine whether canines could be trained to identify patients with cancer by sniffing the urine obtained from a patient with breast or prostate cancer from among samples obtained from healthy volunteers. DESIGN: Dogs of different breeds were trained by their owners to detect the urine sample from a patient with cancer from among 6 other age- and sex-matched healthy volunteers. After the training was completed, using new samples, 2 test runs were used for each patient with breast cancer and three runs for the patients with prostate cancer against the same matched samples. The configuration of the samples was different for each run. A total of 18 and 33 runs were carried out, respectively. RESULTS: For each cohort, specificity and sensitivity were measured. In the breast cancer tests, of 6 dogs, only 2 performed better than chance in specificity and none were more sensitive than chance. For the prostate sample testing, 4 dogs were used. Two performed significantly better than chance in specificity and none in sensitivity. CONCLUSIONS: Although this study did not produce the outcomes desired, the literature supports a potential to use canines for human cancer detection. Better management of urine samples and a more stringent training protocol during our study may have provided new evidence as to the feasibility of using canines for cancer detection. A comparison of the 3 dog cancer scenting studies is also presented.

Case study of the morphologic variation of circulating tumor cells.

We report a detailed cytomorphologic evaluation of the circulating component of widely metastatic breast carcinoma. A previously healthy 38-year-old woman was diagnosed with breast cancer. Wide local excision revealed a 1.7-cm infiltrating ductal adenocarcinoma, BSR score 7/9 with angiolymphatic invasion, and 4/20 lymph nodes positive for carcinoma. Five years later, a bone marrow biopsy revealed involvement of bone marrow by metastatic breast carcinoma, and shortly thereafter, metastases were identified in the liver and lung hilum. She enrolled in a clinical investigation for the detection of circulating tumor cells (CTCs) in breast carcinoma. A total of 659 CTCs were identified in a 10-mL blood sample using an immunofluorescent protocol targeting cytokeratins and detected using fiber-optic array scanning technology. The detected CTCs were subsequently stained with a Wright-Giemsa stain, and representative cells were evaluated in detail by light microscopy for morphologic evaluation. We find that the patient's CTCs exhibit a high degree of pleomorphism including CTCs with high and low nuclear-to-cytoplasmic ratios along with CTCs exhibiting early and late apoptotic changes. In addition, in comparison with her tumor cells in other sites, the full morphologic spectrum of cancer cells present in primary and metastatic tumor is also present in peripheral blood circulation.

High speed detection of circulating tumor cells.

Epithelial tumor cells circulate in peripheral blood at ultra-low concentrations in cancer patients. We have developed an instrument capable of rapid and accurate detection of rare cells in circulation utilizing fiber-optic array scanning technology (FAST). The FAST cytometer can locate immunofluorescently labeled rare cells on glass substrates at scan rates 500 times faster than conventional automated digital microscopy. These high scan rates are achieved by collecting fluorescent emissions using a fiber bundle with a large (50 mm) field of view. Very high scan rates make possible the ability to detect rare events without the requirement for an enrichment step. The FAST cytometer was used to detect, image and re-image circulating tumor cells in peripheral blood of breast cancer patients. This technology has the potential to serve as a clinically useful point-of-care diagnostic and a prognostic tool for cancer clinicians. The use of a fixed substrate permits the re-identification and re-staining of cells allowing for additional morphologic and biologic information to be obtained from previously collected and identified cells.

A randomized phase II study of paclitaxel and bevacizumab with and without gemcitabine as first-line treatment for metastatic breast cancer.

BACKGROUND: The addition of bevacizumab to paclitaxel improved progression-free survival (PFS) of patients with metastatic breast cancer (MBC). We examined the efficacy and safety of adding gemcitabine to paclitaxel/bevacizumab (PB). PATIENTS AND METHODS: In this multicenter, open-label, randomized phase II trial, women with locally advanced or MBC were randomly assigned to receive paclitaxel 90 mg/m(2) (days 1, 8, 15) and bevacizumab 10 mg/kg (days 1, 15) with or without gemcitabine 1500 mg/m(2) (days 1, 15) in 28-day cycles. Patients with prior cytotoxic therapy for MBC were ineligible. The primary endpoint was investigator-assessed overall response rate (ORR); secondary endpoints were PFS, overall survival (OS), safety, and quality of life. RESULTS: Ninety-four patients received PB, and 93 received paclitaxel/bevacizumab/gemcitabine (PB+G). The ORRs were 48.9% (95% confidence interval [CI], 38.5%-59.5%) and 58.7% (95% CI, 47.9%-68.9%; P = .117) with PB and PB+G, respectively. The median PFS was 8.8 months (95% CI, 8.1-10.4 months) and 11.3 months (95% CI, 9.7-12.7 months; P = .247; hazard ratio, 0.82); the median OS was 25.0 months (95% CI, 18.8-not assessable [N/A] months) and 24.3 months (95% CI, 20.3-N/A months; P = .475; hazard ratio, 0.84), with PB and PB+G, respectively. There was significantly more grade 3-4 neutropenia (P = .001) and dyspnea (P = .014) with PB+G. Patients treated with PB experienced more improvement in total FACT-B (Functional Assessment of Cancer Therapy-Breast) (P = .021), FACT-B Social/Family Well-being (P = .041), and Breast Cancer-Additional Concerns (P = .008) scores than patients treated with PB+G. CONCLUSION: The addition of gemcitabine to PB was not associated with a statistically significant improvement in ORR. Treatment with PB+G increased the incidence of severe neutropenia and dyspnea, although the regimen generally was well tolerated.

Phase II, randomized trial to compare anastrozole combined with gefitinib or placebo in postmenopausal women with hormone receptor-positive metastatic breast cancer.

PURPOSE: This phase II randomized trial evaluated the efficacy and tolerability of anastrozole combined with gefitinib or anastrozole with placebo in women with hormone receptor-positive metastatic breast cancer (MBC). EXPERIMENTAL DESIGN: Postmenopausal women with hormone receptor-positive measurable or evaluable MBC who had not received prior endocrine therapy for this disease stage or who developed metastatic disease during/after adjuvant tamoxifen were eligible. The primary response variable was progression-free survival (PFS) and secondary response variables included clinical benefit rate, objective response rate, overall survival, safety and tolerability, and pharmacokinetics. Tumor biomarker evaluation was an exploratory objective. RESULTS: Forty-three patients were randomized to anastrozole plus gefitinib and 50 patients were randomized to anastrozole plus placebo of a planned total of 174 patients (enrollment was prematurely discontinued due to slow recruitment). PFS for patients receiving the combination of anastrozole and gefitinib was longer than for patients receiving anastrozole plus placebo [hazard ratio (gefitinib/placebo), 0.55; 95% confidence interval, 0.32-0.94; median PFS, 14.7 versus 8.4 months]. The clinical benefit rate was 49% versus 34%, and the objective response rate was 2% versus 12% with anastrozole plus gefitinib and anastrozole plus placebo, respectively. No evidence of interaction between baseline biomarker levels and relative treatment effect was found. No unexpected adverse events were observed. CONCLUSION: This small randomized study showed that anastrozole in combination with gefitinib is associated with a marked advantage in PFS compared with anastrozole plus placebo, and that the combination was tolerated in postmenopausal women with hormone receptor-positive MBC. Further investigation of epidermal growth factor receptor inhibition in combination with endocrine therapy may be warranted.

Benefit from exemestane as extended adjuvant therapy after 5 years of adjuvant tamoxifen: intention-to-treat analysis of the National Surgical Adjuvant Breast And Bowel Project B-33 trial.

PURPOSE: Patients with early-stage, hormone receptor-positive breast cancer have considerable residual risk for recurrence after completing 5 years of adjuvant tamoxifen. In May 2001, the National Surgical Adjuvant Breast and Bowel Project (NSABP) initiated accrual to a randomized, placebo-controlled, double-blind clinical trial to evaluate the steroidal aromatase inhibitor exemestane as extended adjuvant therapy in this setting. PATIENTS AND METHODS: Postmenopausal patients with clinical T(1-3)N(1)M(0) breast cancer who were disease free after 5 years of tamoxifen were randomly assigned to 5 years of exemestane (25 mg/d orally) or 5 years of placebo. Our primary aim was to test whether exemestane prolongs disease-free survival (DFS). In October 2003, results of National Cancer Institute of Canada (NCIC) MA.17 showing benefit from adjuvant letrozole in this setting necessitated termination of accrual to B-33, unblinding, and offering of exemestane to patients in the placebo group. RESULTS: At the time of unblinding, 1,598 patients had been randomly assigned; 72% in the exemestane group continued on exemestane and 44% in the placebo group elected to receive exemestane. With 30 months of median follow-up, original exemestane assignment resulted in a borderline statistically significant improvement in 4-year DFS (91% v 89%; relative risk [RR] = 0.68; P = .07) and in a statistically significant improvement in 4-year relapse-free survival (RFS; 96% v 94%; RR = 0.44; P = .004). Toxicity, assessed up to time of unblinding, was acceptable for the adjuvant setting. CONCLUSION: Despite premature closure and crossover to exemestane by a substantial proportion of patients, original exemestane assignment resulted in non-statistically significant improvement in DFS and in statistically significant improvement in RFS.

A6, a urokinase plasminogen activator (uPA)-derived peptide in patients with advanced gynecologic cancer: a phase I trial.

OBJECTIVES: The aim of this study was to define the toxicity, maximum feasible dose (MFD), and pharmacokinetics (PK) of A6, a peptide derived from human urokinase plasminogen activator (uPA), in patients with advanced gynecologic cancers, and to explore anti-tumor activity and the effects of A6 on biomarkers of the urokinase system. METHODS: A6 was administered subcutaneously daily, and doses were escalated in cohorts of three to six subjects. Serial blood specimens were obtained for pharmacokinetics and levels of urokinase plasminogen activator (uPA), uPA receptor (uPAR), and plasminogen activator inhibitor-1 (PAI-1). RESULTS: Sixteen patients were enrolled and eligible for evaluation. No serious drug-related adverse events or dose-limiting toxicity occurred. A6-related toxicities were limited to grades 1 and 2 adverse effects including local injection site reactions. Five patients had stable tumor measurements for at least 4 cycles, one of whom stayed on study for 12 months. One patient had a confirmed cancer antigen (CA)-125 response (decrease in CA-125 of >50%) with stable disease on CT scan after 14 cycles and continues on study. Time to peak plasma level of A6 was 1-2 h. C(max) is proportional to dose. The half-life of A6 was approximately 2 h. Baseline biomarker levels did not predict response and trends over time did not correlate with outcome. CONCLUSIONS: A6 given daily continuously is well tolerated at all dose levels, without any dose-limiting toxicity. Based on the preliminary activity of A6, a phase II trial is underway in ovarian cancer.