Susan Fox

A phase II study of paclitaxel and ifosfamide for patients with advanced refractory carcinoma of the urothelium

Cisplatin‐based combination chemotherapy for patients with advanced transitional cell carcinoma (TCC) of the urothelium has limitations, and new therapies need to be evaluated.

A phase II trial of paclitaxel in refractory germ cell tumors

A significant percentage of patients with refractory germ cell tumors will not respond to standard salvage regimens. Thus there is a need for new active agents. Paclitaxel has demonstrated activity against a variety of solid tumors in both laboratory and clinical studies.

Learning to Refine Indexing by Introspective Reasoning

A significant problem for case-based reasoning (CBR) systems is determining the features to use in judging case similarity for retrieval. We describe research that addresses the feature selection problem by using introspective reasoning to learn new features for indexing. Our method augments the CBR system with an introspective reasoning component which monitors system performance to detect poor retrievals, identifies features which would lead retrieval of more adaptable cases, and refines the indexing criteria to include the needed features to avoid future failures. We explore the benefit of introspective reasoning by performing empirical tests on the implemented system. These tests examine the effect of introspective index refinement, and the effects of problem order on case and index learning, and show that introspective learning of new index features improves performance across the different problem orders.

Introspective reasoning for index refinement in case-based reasoning

Introspective reasoning can enable a reasoner to learn by refining its own reasoning processes. In order to perform this learning, the system must monitor the course of its reasoning to detect learning opportunities and then apply appropriate learning strategies. This article describes lessons learned from research on a computer model of how introspective reasoning can guide failure-driven learning. The computer model monitors its own reasoning by comparing it to a model of the desired behaviour of its reasoning, and learns in response to deviations from the ideal defined by the model. The approach is applied to the problem of determining indices for selecting cases from a case-based planners memory. Experiments show that learning driven by this introspective reasoning both decreases retrieval effort and improves the quality of plans retrieved, increasing the overall performance of the planning system compared to case learning alone.

Paclitaxel plus gallium nitrate and filgrastim in patients with refractory malignancies: a phase I trial.

To determine the maximally tolerated dose of paclitaxel with and without filgrastim (G-CSF) when administered as a 24-hour intravenous infusion after a 120-hour infusion of gallium nitrate at a fixed dose of 300 mg/m2/24 hours, 40 patients were entered onto a trial lasting from September 1994 to September 1996. Eligibility included a diagnosis of an advanced malignancy not amenable to curative therapy and up to one previous chemotherapy regimen for metastatic disease. Gallium was administered at a fixed dose of 300 mg/m2/day as a continuous intravenous infusion for 120 hours. Paclitaxel starting at 90 mg/m2 was given concurrently with the last 24 hours of the gallium as a 24-hour intravenous infusion. Cycles were repeated every 21 days. Once the maximum tolerated dose (MTD) of paclitaxel was reached, G-CSF (5 microg/kg/day days 7-16) was added and paclitaxel dose escalation continued. The MTD for paclitaxel without G-CSF was 110 mg/m2 and 225 mg/m2 with G-CSF, with neutropenia being the dose-limiting toxicity. A partial response was noted in a patient who had thymoma and a complete response was achieved in a patient who had colon cancer. The recommended phase II dosage is gallium nitrate at 300 mg/m2/day over 120 hours, with paclitaxel at 110 mg/m2 over 24 hours without G-CSF or 225 mg/m2 over 24 hours with G-CSF and 0.5 mg calcitriol on days 1 through 7. Further trials of this modified regimen for outpatient administration are in progress.

Paclitaxel (Taxol) plus doxorubicin plus filgrastim in advanced sarcoma: a phase II study.

The authors evaluated the novel chemotherapeutic regimen of paclitaxel (Taxol, Bristol-Myers Squibb, Princeton, NJ, U.S.A.) plus doxorubicin plus filgrastim--a granulocyte colony-stimulating factor (G-CSF)--in advanced or metastatic sarcoma. Eligible patients must have had histologically confirmed advanced previously untreated soft-tissue sarcoma. All patients must have had bidimensionally measurable metastases. Treatment consisted of doxorubicin, 50 mg/m2 by intravenous push, followed 4 hours later by paclitaxel, 150 mg/m2 by continuous infusion over 24 hours every 3 weeks, plus G-CSF, 5 microg/kg, on days 3 through 12 of each cycle. Cycles were repeated every 21 days. A one-time dose escalation for doxorubicin only (60 mg/m2) was allowed in all patients who experienced no significant toxicity after their first cycle of paclitaxel plus doxorubicin. From November 1993 through May 1996, 29 patients were entered in this study. Grade 3 anemia occurred in three patients. Grade 3--4 neutropenia occurred in 20 patients. Seven patients experienced at least one episode of neutropenic fever, including one death. Grade 3 thrombocytopenia occurred in four patients. There were six partial responses in 27 eligible patients, for a response rate of 22.2% (95% confidence interval, 7%-38%). Median time to progression was 4.5 months, and median overall survival was 10.2 months. The regimen of paclitaxel plus doxorubicin plus filgrastim as used in this study appears to have no more activity than single-agent doxorubicin.

A Unified CBR Architecture for Robot Navigation

A delivery robot navigating in the real world and contending with multiple goals and priorities benefits from combining deliberative and reactive planning. Deliberative planners anticipate and optimize actions, and manage multiple goals at once. Reactive planners respond flexibly and moment-to-moment to a changing world, based on incomplete and flawed knowledge. This project proposes using case-based reasoning to fully integrate high-level and low-level planning techniques, along with other reasoning tasks of the system. The resulting robot allows case selection to mediate between methods. In addition, the robot learns by recording new reactive behaviors, storing new plans it creates, and introspective learning of retrieval features.

Green computing in the introductory curriculum (abstract only)

Green computing is a catchall phrase that includes efforts to improve sustainability both within the IT industry and outside of it. The green IT movement seeks to reduce energy use, waste, and toxic substances by the IT industry. In many other industries, mobile and computing devices connected to the network enable sustainability through automation, virtualization, and reduced travel. Green computing is a topic of increasing importance within the IT industry. There are few green computing courses for undergraduates, and most are for advanced students. I present a CS1 Lite course centered on the theme of green computing. The course integrates programming activities with readings, discussion and online research. The first course module examined how the Internet and mobile networks enable sustainable practices, such as: the virtualization of goods and services, telecommuting and virtual meetings, and cloud computing. The second module examined the Green IT movement, including sustainability across the computer life cycle, and increasing energy efficiency, from individual computers up to data centers. The third module focused on Smart Technology, where network-connected computing devices drive improvements. Topics included the smart energy grid, smart buildings, and applications in health care and agriculture. Throughout the course, programming assignments were tailored to problems relevant to the green computing topics. Students implemented simulations of green computing systems. Students exhibited increased interest and motivation for these projects, and learned naturally about data abstraction and computer networks.

A Phase II Trial of Paclitaxel in Refractory Germ Cell Tumors

BACKGROUNDnA significant percentage of patients with refractory germ cell tumors will not respond to standard salvage regimens. Thus there is a need for new active agents. Paclitaxel has demonstrated activity against a variety of solid tumors in both laboratory and clinical studies.nnnMETHODSnEighteen patients with refractory germ cell tumors who failed initial cisplatin-based chemotherapy and a maximum of 2 salvage regimens were enrolled into a Phase II trial of paclitaxel at a dose of 170 mg/m2 by intravenous infusion over 24 hours every 21 days without growth factor support. The median age of the patients was 32.5 years (range, 18-49 years). The testis was the primary site of tumor for 13 patients (72%) and the tumor was extragonadal in 5 patients (28%). Six patients (33%) were late recurrences. Twelve patients (67%) had > or = 2 metastatic sites. The median number of previous chemotherapy cycles was six (range, four to nine). Three patients (17%) previously had undergone autologous bone marrow transplantation.nnnRESULTSnTwo patients (11%) responded to paclitaxel. Major toxicities were Grade 3-4 neutropenia (55% of patients) and Grade 3-4 neurotoxicity (2 patients). Neutropenic fever occurred in 3 patients (17%).nnnCONCLUSIONSnPaclitaxel demonstrated minimal activity in heavily pretreated patients with multiple, poor risk clinical features. These results in part may be due to the unfavorable characteristics of the patients in the current study, specifically the high percentage of patients with late recurrences and extragonadal primary tumors, both of which are known to respond poorly to salvage therapy. Other trials with different patient populations and doses of paclitaxel reported response rates ranging from 13.3%-26%. The role of paclitaxel in the treatment of patients with refractory germ cell tumors remains to be defined in future studies.