JPH05137803A - Treating element for combined chemo-and thermo-therapy - Google Patents

Abstract

PURPOSE:To provide a treating element capable of controlling a carcinostatic substance given to the affected part, injecting it through catheter and indwelling needle and treatment the chemo-and thermo-therapy against cancer at the same time. CONSTITUTION:The surface of a magnetic material 1 having 42-90 deg.C of Qurie temperature is coated with a noble metal harmless to the living body, and covered with a carcinostatic substance 3 or it is deposited thereon. Further, the carcinostatic substance 3 is coated with a temperature sensitive polymer 4 melted at 40-70 deg.C to constitute a thermotherapy element for curing cancer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal element for treating cancer, more specifically, a method for treating malignant tumors such as cancer.
The present invention relates to a thermotherapy device for cancer treatment, which can be used as an implant material for local heating in a magnetic induction system in hyperthermia (hyperthermia), which is a seed, and can be used in combination with cancer chemotherapy by releasing an anticancer drug.

[0002]

2. Description of the Related Art The usual method of drug administration in cancer chemotherapy is systemic administration by intravenous injection using a syringe. However, side effects due to toxicity of the drug to be administered have become a problem. That is, the anti-cancer agent has similar toxicity exertion values to tumor cells and normal cells regardless of their origin and action. Therefore, how to selectively concentrate the anti-cancer agent on the cancer cells and make it act for a long time is a problem.

As a method for solving the above problems, research on microcapsules and microspheres has been conducted. The microcapsule has a mechanism in which an anticancer agent is put in the capsule and the anticancer agent can be gradually released into the living body through the outer wall of the capsule. In addition, since the microcapsules themselves have no tumor tropism, chemoembolization therapy by selective injection into the tumor-dominant artery is mainly applied. However, the control of anticancer drug administration in microcapsules depends on the physical and physical properties of the outer wall constituents.
It has the drawback that it is easily determined by its chemical properties and structure, and that it cannot be controlled artificially.

Microspheres are particles in which an anticancer agent is dispersed in albumin microspheres used as a blood circulation system contrast agent. However, since albumin microspheres may swell or dissolve in an aqueous solution, the release behavior of the contained drug becomes complicated, and it is difficult to control artificial release.

As a mechanism for artificially releasing an anticancer drug by some method, a drug releasing element to which a magnetic material is applied is described in Japanese Utility Model Publication No. 2-35750. This element is
Since it is a ferrite sintered body, an incision operation is required to implant it in the living body. Further, the drug release control is performed by the heat generation of the magnetic body by applying a magnetic field, but since it is a ferrite sintered body, the heat generation of the sintered body differs depending on the magnetic field application direction, so it is considered that actual release control is difficult.

[0006] In recent years, the therapeutic effect of cancer by the combined use of chemotherapy for cancer and hyperthermia has been revealed. As a reason for enhancing the lethal effect of cancer cells by the combined use, a compensatory effect due to the difference between the hypersensitive cancer cell cycle (cell age) by hyperthermia and the hypersensitive cancer cell cycle by anticancer agents, the prevention of cancer recurrence by heating when the anticancer agent effects decrease, and It can be mentioned that the cancer cell membrane permeability of the anticancer agent is increased by heating.

[0007] In general, local hyperthermia often uses electromagnetic waves. If the frequency is increased, local heating is possible but deep heating becomes difficult, and if the frequency is lowered, deep heating is facilitated. It has an essential problem of widening the heating range. If the temperature inside the living body is not measured and the measured temperature is not used for feedback control of the electromagnetic wave output, the temperature of the heated portion of the living body rises excessively, which may be harmful to the living body.

A method called soft heating method is being developed in recent years to cover the problems of hyperthermia applying these electromagnetic waves. In this method, a temperature-sensitive magnetic material is embedded in a tumor part in a living body, and a hysteresis loss or the like generated by exciting with a high-frequency magnetic field is used as a heat source to heat. According to this method, since the treatment temperature is determined by the Curie temperature of the temperature sensitive element, it is not necessary to adjust the electromagnetic wave output.

[0009]

From the above, the problem to be solved by the present invention is to artificially control the local administration of an anticancer agent so that implantation in a living body does not damage the patient as much as possible. Can be injected with a catheter or indwelling needle,
Moreover, the local heating is performed by the soft heating method which does not require the adjustment of the electromagnetic wave output and the temperature measurement, and the combined treatment of the cancer chemotherapy and the hyperthermia is intended to be performed by one type of element.

Therefore, an object of the present invention is to treat cancer heat which can be used as an implant material for local heating in a soft heating method in a magnetic induction system and can be used in combination with cancer chemotherapy by controlling artificial release of an anticancer agent. It is to provide an element.

[0011]

As a result of various studies to solve the above problems, the surface of a magnetic powder having a Curie temperature of 42 ° C. to 90 ° C. and a scaly powder form is coated with a noble metal. An anti-cancer agent was coated on the above, and a temperature-sensitive magnetic powder was further coated thereon with a temperature-sensitive polymer, and when a high-frequency alternating magnetic field of 200 kHz / 3400 A / m was applied in physiological saline, the heating element of the present invention. It was discovered that the temperature-sensitive polymer film melts and the release of the anticancer drug can be controlled artificially by heating, and the temperature-sensitive polymer film and the anticancer drug melt and disperse, and It was confirmed that hyperthermia is possible.

Further, the surface of the scale-like temperature-sensitive magnetic powder is
It was also confirmed that by coating with a noble metal such as u and Pt, the rate of temperature rise of the temperature-sensitive magnetic powder was increased when a high frequency alternating magnetic field was applied, and the temperature was raised to a predetermined temperature in a short time.

In the present invention, the anticancer agent need not be coated on the entire surface of the temperature-sensitive magnetic powder, but may be a scattered coating. The anticancer agent can be coated by determining the required addition amount from the amount of the element of the present invention to be injected. The coating method includes chemical, physicochemical, and physical methods. As a simple method, the surface of the magnetic substance can be coated with the anticancer agent by mechanical granulation.

The temperature-sensitive polymer film must be melted at 40 to 70 ° C. As a polymer having a melting temperature in this range, a wax contained in a suppository, a polymer of polyacrylic amide and butyl methacrylate, or a complex of a low-melting polymer harmless to the living body is considered. 4 thermosensitive polymers
When the temperature is 0 ° C or lower, the polymer film may melt without being applied with a high frequency alternating magnetic field when injected into a living body, and when the temperature is 70 ° C or higher, the temperature-sensitive magnetic powder generates heat. However, the polymer film does not melt sufficiently. A preferable melting temperature range is 42 to 50 ° C.

Further, the Curie temperature of the temperature-sensitive magnetic powder is
In the range of 42 to 90 ° C, it is necessary to be higher than the melting point of the polymer film. Magnetic materials having a Curie temperature in the range of 42 to 90 ° C. are disclosed in JP-A-2-47243 and JP-A-2-47243.
There are temperature-sensitive amorphous alloys, Fe-Pt alloys, and the like described in Japanese Patent Laid-Open No. 61036. This is because if the Curie temperature is less than 42 ° C., it is not possible to heat the treatment temperature range effective as hyperthermia, and if it exceeds 90 ° C., the treatment temperature range of hyperthermia is exceeded and overheating occurs. The preferred Curie temperature range is 45-55 ° C. The device of the present invention can be specifically injected into a living body by using a catheter or the like by setting the device particle size to 150 μm or less.

[0016]

[Example] JP-A-2-4724 with Curie temperature of 50 ° C
Outline of the element of the present invention in which the temperature-sensitive magnetic powder described in Japanese Patent No. 3 is coated with Au noble metal, further coated with an anticancer agent, and further coated with a temperature-sensitive polymer complex for suppositories that melts at 43 ° C. The figure is shown in FIG. 1 is a scale-like temperature-sensitive magnetic powder, 2
Is a coating made of the noble metal Au. Although 3 is an anticancer agent, it is not necessary to cover the entire surface of the magnetic powder. Reference numeral 4 is a film made of a temperature-sensitive polymer.

FIG. 2 shows temperature rising characteristics when a high frequency magnetic field having a frequency of 200 kHz and a magnetic field strength of 3400 A / m was applied in physiological saline after the polymer film was melted and dispersed. It took 5 minutes to reach the treatment temperature of hyperthermia when the element not covered by the noble metal Au was applied with the same high frequency magnetic field, whereas the treatment temperature was reached within 3 minutes. Prove.

[0018]

EFFECTS OF THE INVENTION By using the thermotherapy device for cancer treatment according to the present invention, it is possible to artificially and effectively control the release of the anticancer drug to the cancer cells, and further control the self-temperature of the residual magnetic powder after the release of the anticancer drug. Hyperthermia therapy can be done quickly.

[Brief description of drawings]

FIG. 1 is a schematic view showing an example of a combined therapeutic and thermal treatment device according to the present invention.

FIG. 2 is a graph showing a temperature rise characteristic when a high frequency magnetic field is applied to the device according to the present invention.

[Explanation of symbols]

 1 magnetic material 2 noble metal film 3 anticancer agent 4 temperature-sensitive polymer film

Front page continuation (72) Inventor Koji Hemi 4-14 Suehiro, Kumagaya-shi, Saitama Riken Kumagaya Works

Claims (1)

[Claims] 1. A surface of a magnetic material having a Curie temperature of 42 ° C. to 90 ° C. is coated with a noble metal which is harmless to a living body, and further coated with or adhered with an anticancer agent, and further 40
A thermal element for cancer treatment, characterized by being coated with a temperature-sensitive polymer that melts at ˜70 ° C.