4,937 research outputs found
Model-based Angiogenic Inhibition of Tumor Growth using Modern Robust Control Method
Cancer is one of the most destructive and lethal illnesses of the modern civilization.
In the last decades, clinical cancer research shifted towards molecular targeted therapies
which have limited side e�ects in comparison to conventional chemotherapy and radiation
therapy. Anti-angiogenic therapy is one of the most promising cancer treatment methods. The
dynamical model for tumor growth under angiogenic stimulator/inhibitor control was posed
by Hahnfeldt et al. (1999), and it was investigated and partly modi�ed many times. In this
paper, a modi�ed version of the originally published model is used in order to describe a
continuous infusion therapy. To generalize individualized therapies a robust control method
is proposed using
H
1
methodology. Uncertainty weighting functions are determined based on
the real pathophysiological case and simulations are performed on di�erent tumor volumes to
demonstrate the robustness of the proposed method
Parameter optimization of H∞ controller designed for tumor growth in the light of physiological aspects
According to the fact that cancer diseases are leading causes of death all around the world, development of cancer fighting therapies is necessary. Beside the medical knowledge, there is an extra need for engineering approach to solve this complex problem. The aim of this paper is to design controller for tumor growth under angiogenic inhibition, which on the one hand minimizes the input signal as far as possible (in order to have less side effects and greater cost-effectiveness) and on the other hand results in appropriately low tumor volume. Since the model contains uncertainties and measurement noise, the controller was designed using modern robust control methodology. Choosing of the ideal system and the weighting functions were done in the light of physiological aspects
Potential Benefits of Discrete-Time Controllerbased Treatments over Protocol-based Cancer Therapies
In medical practice, the effectiveness of fighting cancer is not only determined by
the composition of the used drug, but determ
ined by the administration method as well. As
a result, having drugs with
a
suitable action profile is just a promising beginning, but
without appropriate delivery method
s
, the therapy still can be ineffective.
Finding the
optimal biologic dose is an empir
ical process in medical practice; however, using
controllers, an automated optimal administration can be
determined
.
In this paper
,
we
evaluate the effectiveness of
different drug delivery
protocols;
using in silico simulations
(like bolus dose
s,
low
-
dose
metron
omic regimen and
continuous infusion therapy
). In
addition, we compare these results with discrete
-
time controller
-
based treatments
containing state feedback, setpoint control, actual state observer and load estimation
Study of Modern Control Methodologies Applied to Tumor Growth under Angiogenic Inhibition
Cancer treatment is one of the most important research fields
of modern medicine.
In the last decades, targeted molecular therapies showed pr
osperous results. These treatments
achieve tumor regression with limited side-effects. Mathem
atical models were posed which
describe the dynamics of tumor regression under the applied
control. The current paper
investigates antiangiogenic therapy, which inhibits the t
umor to grow its own endothelial
capillaries and thus inhibits tumor to grow over a certain si
ze. Many different control approaches
were elaborated and published since the model formulation w
as posed. The aim of this paper
is to give an overview of these methods and results, and to rev
iew the work carried out by the
authors
Model-based Angiogenic Inhibition of Tumor Growth using Adaptive Fuzzy Techniques
Fighting tumors is one of the most important problems of medical research. In this paper, antiangiogenic cancer therapy is investigated through its mathematical model.This tumor treatment method targets the endothelium of a growing tumor and belongs to the targeted molecular therapies.The aim of the therapy is not to eliminate the entire tumor,but to decrease the tumor to a minimal volume. An advantage of applying antiangiogenic treatment is that tumor cells show lower tendency of becoming resistant to the applied drugs.Adaptive fuzzy control is implemented for a simplified model to elaborate a control technique which is able to handle the effects of parameter perturbations and uncertainties while keeping the daily and total inhibitor inlet under a given limit
Comparison of Path Tracking Flat Control and Working Point Linearization Based Set Point Control of Tumor Growth with Angiogenic Inhibition
Targeted molecular therapies (TMT) represent new perspectives in cancer treatment, fighting against the specific characteristic of the investigated tumor. Antiangiogenic therapy represents a specific TMT and its role is to stop the angiogenesis of the tumor, the process of forming new blood vessels; hence, to stop tumor growth. Proper control algorithms for tumor growth control with angiogenic inhibition are analyzed in the current article in order to find optimal therapeutic protocols. Two slightly different approaches are compared: nonlinear control by exact linearization with path tracking control, and linear control by working point linearization with set point control. The control strategies are compared in terms of the characteristics of the input signal (the inhibitor, drug intake) that is crucial if the therapy will be put into practice
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